Astrocytic endothelin-1 overexpression impairs learning and memory ability in ischemic stroke via altered hippocampal neurogenesis and lipid metabolism

Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However,the way in which changes in astrocytic endothelin-1 lead to poststroke cognitive deficits following transient middle cerebral artery occlusion is not well understood.Here,using mice in which astrocytic endothelin-1 was overexpressed,we found that the selective overexpression of endothelin-1 by astrocytic cells led to ischemic stroke-related dementia(1 hour of ischemia;7 days,28 days,or 3 months of reperfusion).We also revealed that astrocytic endothelin-1 overexpression contributed to the role of neural stem cell proliferation but impaired neurogenesis in the dentate gyrus of the hippocampus after middle cerebral artery occlusion.Comprehensive proteome profiles and western blot analysis confirmed that levels of glial fibrillary acidic protein and peroxiredoxin 6,which were differentially expressed in the brain,were significantly increased in mice with astrocytic endothelin-1 overexpression in comparison with wild-type mice 28 days after ischemic stroke.Moreover,the levels of the enriched differentially expressed proteins were closely related to lipid metabolism,as indicated by Kyoto Encyclopedia of Genes and Genomes pathway analysis.Liquid chromatography-mass spectrometry nontargeted metabolite profiling of brain tissues showed that astrocytic endothelin-1 overexpression altered lipid metabolism products such as glycerol phosphatidylcholine,sphingomyelin,and phosphatidic acid.Overall,this study demonstrates that astrocytic endothelin-1 overexpression can impair hippocampal neurogenesis and that it is correlated with lipid metabolism in poststroke cognitive dysfunction.

Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice

Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction.

Dry environment on the expression of lacrimal gland S100A9,Anxa1,and Clu in rats via proteomics

●AIM:To investigate the underlying mechanism of dry environment(autumn dryness)affecting the lacrimal glands in rats.●METHODS:Twenty Sprague-Dawley rats were randomly divided into two groups.The rats were fed in specific pathogen free environment as the control group(n=10),and the rats fed in dry environment as the dryness group(n=10).After 24d,lacrimal glands were collected from the rats.The tissues morphology was observed by hematoxylineosin(HE)staining.Tandem mass tags(TMT)quantitative proteomics analysis technology was used to screen the differential expressed proteins of lacrimal glands between the two groups,then bioinformatics analysis was performed.Further,the immunohistochemical(IHC)method was used to verify the target proteins.●RESULTS:In dryness group,the lacrimal glands lobule atrophied,the glandular cavities enlarged,the sparse nuclear distribution and scattered inflammatory infiltration between the acinus were observed.The proteomics exhibited that a total of 195 up-regulated and 236 downregulated differential expressed proteins screened from the lacrimal glands of rats.It was indicated that the biological processes(BP)of differential expressed proteins mainly included cell processes and single BP.The cellular compositions of differential expressed proteins mainly located in cells,organelles.The molecular functions of differential expressed proteins mainly included binding,catalytic activity.Moreover,the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis showed that the differential expressed proteins mainly involved lysosome,complement and coagulation cascade,and ribosome pathway.The IHC result verified that the up-regulated expression proteins of Protein S100A9(S100A9),Annexin A1(Anxa1),and Clusterin(Clu)in lacrimal glands of rats in dryness group were higher than control group.●CONCLUSION:The up-regulated expression proteins of S100A9,Anxa1,and Clu may be the potential mechanisms of dry eye symptoms caused by dry environment.This study provides clues of dry environments causing eye-related diseases for further studies.

EfficientNetB1 Deep Learning Model for Microscopic Lung Cancer Lesion Detection and Classification Using Histopathological Images

Cancer poses a significant threat due to its aggressive nature,potential for widespread metastasis,and inherent heterogeneity,which often leads to resistance to chemotherapy.Lung cancer ranks among the most prevalent forms of cancer worldwide,affecting individuals of all genders.Timely and accurate lung cancer detection is critical for improving cancer patients’treatment outcomes and survival rates.Screening examinations for lung cancer detection,however,frequently fall short of detecting small polyps and cancers.To address these limitations,computer-aided techniques for lung cancer detection prove to be invaluable resources for both healthcare practitioners and patients alike.This research implements an enhanced EfficientNetB1 deep learning model for accurate detection and classification using histopathological images.The proposed technique accurately classifies the histopathological images into three distinct classes:(1)no cancer(benign),(2)adenocarcinomas,and(3)squamous cell carcinomas.We evaluated the performance of the proposed technique using the histopathological(LC25000)lung dataset.The preprocessing steps,such as image resizing and augmentation,are followed by loading a pretrained model and applying transfer learning.The dataset is then split into training and validation sets,with fine-tuning and retraining performed on the training dataset.The model’s performance is evaluated on the validation dataset,and the results of lung cancer detection and classification into three classes are obtained.The study’s findings show that an enhanced model achieves exceptional classification accuracy of 99.8%.

Key elements determining the intestinal region-specific environment of enteric neurons in type 1 diabetes

Diabetes,as a metabolic disorder,is accompanied with several gastrointestinal(GI)symptoms,like abdominal pain,gastroparesis,diarrhoea or constipation.Serious and complex enteric nervous system damage is confirmed in the background of these diabetic motility complaints.The anatomical length of the GI tract,as well as genetic,developmental,structural and functional differences between its segments contribute to the distinct,intestinal region-specific effects of hyperglycemia.These observations support and highlight the importance of a regional approach in diabetes-related enteric neuropathy.Intestinal large and microvessels are essential for the blood supply of enteric ganglia.Bidirectional morpho-functional linkage exists between enteric neurons and enteroglia,however,there is also a reciprocal communication between enteric neurons and immune cells on which intestinal microbial composition has crucial influence.From this point of view,it is more appropriate to say that enteric neurons partake in multidirectional communication and interact with these key players of the intestinal wall.These interplays may differ from segment to segment,thus,the microenvironment of enteric neurons could be considered strictly regional.The goal of this review is to summarize the main tissue components and molecular factors,such as enteric glia cells,interstitial cells of Cajal,gut vasculature,intestinal epithelium,gut microbiota,immune cells,enteroendocrine cells,prooxidants,antioxidant molecules and extracellular matrix,which create and determine a gut region-dependent neuronal environment in diabetes.

基于Sentinel-1/2改进极化指数和纹理特征的土壤含盐量反演模型

目前Sentinel-1/2协同反演植被土壤含盐量的研究大多是基于Sentinel-2光谱信息和Sentinel-1后向散射系数,没有考虑Sentinel-2光谱信息容易受土壤亮度等信息影响,Sentinel-1后向散射系数容易受土壤粗糙度和水分影响。为进一步提高Sentinel-1/2协同反演植被土壤含盐量的精度,用水云模型对雷达卫星后向散射系数进行校正,消除植被影响;然后协同Sentinel-2纹理特征,基于VIP、OOB、PCA 3种变量筛选和RF、ELM、Cubist 3种机器学习回归模型构建植被土壤含盐量反演模型。研究结果表明:经过水云模型去除植被影响后的雷达后向散射系数及其极化组合指数与土壤含盐量的相关性有一定程度的提高。不同变量选择方法与不同机器学习方法耦合模型在反演土壤含盐量中,OOB变量筛选方法与RF、ELM和Cubist 3种机器学习方法的耦合模型精度最佳,建模集和验证集的R2都在0.750以上,且验证集的RMSE和MAE均最小;其中OOB-Cubist耦合模型精度最高,且R_(v)^(2)/R_(c)^(2)为0.955,具有良好的鲁棒性。研究可为机器学习协同物理模型、光学卫星协同雷达卫星在土壤含盐量反演中的进一步应用提供思路。

塔里木盆地顺北1号断裂带奥陶系碳酸盐岩储层结构表征及三维地质建模

综合利用地震、测井、岩心以及动态生产资料,对塔里木盆地顺北1号断裂带断控型碳酸盐岩储集体的内部结构进行了层级划分;基于层级划分,通过地震资料属性提取与转换、深度学习、基于目标示性点过程模拟以及离散裂缝网络模拟(DFN)等方法建立了三维地质模型,并以模型进行油气储量和油藏数值模拟,将拟合结果与实际生产数据进行对比。研究结果表明:(1)顺北1号断裂带奥陶系断控型储层按层级由大到小分为走滑断裂影响带、断控体、类洞穴、类洞穴内簇充填和裂缝带共5个层级。(2)走滑断裂影响带受应力差异影响具有分段性,可细分为挤压段、拉分段和平移段;断控体在拉分段发育断裂交会型、单支走滑型,在平移段发育双断裂交错型和两断裂交会型,在挤压段发育双断裂扭曲型和双断裂交会型,共有6种平面组合样式;类洞穴在地震剖面上呈串珠状反射特征;类洞穴内部分为栅体与栅间(基岩),其中栅体又可进一步分为簇(角砾带)、簇间(裂缝带),整体表现为栅状结构,簇的物性更好;裂缝带为类洞穴的主要储集空间,在簇内部比簇间更发育,在一间房组比鹰山组更发育,一间房组和鹰山组均以发育高角度裂缝为主,在两者连接处则以发育水平缝为主。(3)地质模型预测的油气储量与地质分析储量误差为1.75%,模型模拟的生产井地层压力及累产液结果与生产动态吻合度较高,拟合误差小于10%。

1型神经纤维瘤病发病机制及治疗进展

1型神经纤维瘤病(neurofibromatosis type 1,NF1)是一种常见的遗传性神经皮肤综合征,发病率为1/3500,主要表现为皮肤、神经、骨骼等多个系统的肿瘤形成。NF1基因突变导致神经纤维蛋白功能丧失,受神经纤维蛋白负调控的Ras信号失去抑制,导致MAPK信号通路组成型激活,该信号通路的异常激活与肿瘤微环境等机制促使NF1肿瘤发生。目前,主流的治疗方式包括针对Raf/MEK/ERK通路和/或mTOR通路的靶向抑制剂。近年来,对NF1的遗传学、临床特征、肿瘤起源、异常信号通路以及相关靶向抑制剂的疗效等方面的研究日益增多。深入了解NF1的病理生物学和分子机制将为开发更有效的靶向治疗方法提供坚实的基础。

基于GF-1卫星遥感反演排水河沟水体溶存N_(2)O浓度模型对比研究

[目的]探究利用GF-1卫星数据反演水体溶存氧化亚氮(N_(2)O)浓度的可行性,为实现低成本、高效率的水质实时监测提供有效途径。[方法]以宁夏青铜峡灌区第1和第5排水河沟为研究对象,选取与排水河沟水体溶存N_(2)O浓度相关性高的GF-1卫星影像波段反射率和水质参数作为自变量,通过最优子集筛选法确定最优自变量组合,分别构建了多元线性回归、BP神经网络和支持向量机模型,对水体溶存N_(2)O浓度进行预测对比。[结果]水温(T)、溶解性有机碳(DOC)等是影响水体溶存N_(2)O浓度的主要因素,同时近红外(NIR)等卫星波段与水体溶存N_(2)O浓度变化趋势显著相关。当自变量包括T,NIR等7个因素时,模型预测效果最佳。在3种模型中,BP神经网络模型验证结果R^(2)为0.64,具有最高预测精度。[结论]GF-1卫星数据以及水质参数与水体溶存N_(2)O浓度存在复杂的相关性关系,且BP神经网络能够实现利用GF-1卫星数据较高精度地反演水体溶存N_(2)O浓度。

猪场环境源大肠杆菌的耐药性调查及携带mcr-1和tet(X4)菌株的传播特征

养殖场中抗菌药的长期使用促使耐药菌株快速出现和传播,并可以通过粪肥和污水向环境排放,给公共卫生带来巨大威胁。为了调查猪场环境源大肠杆菌的耐药情况,评估耐药基因的传播风险,本试验采集163份猪场粪便、污水和土壤样本,通过平板划线分离培养法分离大肠杆菌,通过药敏试验检测分离菌株对14种抗菌药物的耐药情况,聚合酶链式反应(PCR)检测临床重要耐药基因,脉冲场凝胶电泳(PFGE)检测菌株间的亲缘关系,接合试验和质粒复制子分型检测接合子的质粒类型。结果显示,共分离获得150株大肠杆菌,其中粪便源大肠杆菌耐药情况最严重,污水源大肠杆菌次之,土壤源大肠杆菌最低;污水源大肠杆菌耐药基因检出种类最多,粪便源大肠杆菌次之,土壤源大肠杆菌最少。10株携带黏菌素耐药基因mcr-1大肠杆菌和18株携带替加环素耐药基因tet(X4)大肠杆菌分离自粪便和污水样本,且多重耐药情况较为严重。10株携带mcr-1大肠杆菌经PFGE分为9种脉冲场图谱,其中9株与大肠杆菌C600接合成功,接合子中有IncFIA、IncW、IncFIB、IncI2和IncP五种质粒类型;18株携带tet(X4)大肠杆菌经PFGE分为15种脉冲场图谱,其中16株与大肠杆菌C600接合成功,接合子中有IncFIB、IncFrepB和IncHI1三种质粒类型。结果表明,必需持续监测猪场环境中的临床重要耐药基因,特别需要关注mcr-1和tet(X4)基因的流行情况,并且在养殖中合理使用黏菌素和四环素类抗生素。

慢性间断缺氧通过上调大鼠海马HMGB1和NF-κB损伤学习记忆

目的:探索慢性间断缺氧(CIH)导致大鼠学习记忆功能障碍,以及对海马区高迁移率族蛋白1(HMGB1)和核转录因子-κB(NF-κB)表达的影响。方法:制作CIH大鼠模型,40只SD大鼠分为常氧组(normoxia)、缺氧4周组(CIH4组)、缺氧8周组(CIH8组)和缺氧12周组(CIH12组)。采用Morris水迷宫评估大鼠学习记忆能力,免疫组织化学染色和ELISA法检测大鼠海马区HMGB1和NF-κB的表达。结果:与常氧组相比,CIH12和CIH8组的逃避潜伏期延长,穿越平台次数和平台所在象限停留时间显著缩短,CIH4组的无显著差异。另外,常氧组海马区HMGB1和NF-κB的表达未见明显表达,CIH4组可见少许表达,CIH8组和CIH12组可见明显表达,同时CIH12组的表达显著高于CIH8组。结论:CIH可导致大鼠的学习记忆功能下降,且间断缺氧时间越长对其学习记忆功能的影响越显著。此外,CIH还导致海马区HMGB1和NF-κB的表达水平升高,并且缺氧12周比8周增加更为明显。

苏里格气田S区块山西组山1段沉积微相特征研究

上古生界山西组山1段为鄂尔多斯盆地苏里格气田S区块的主力产气层,厘清其沉积相特征,对指导该地区的天然气勘探具有一定意义。运用沉积学基础原理和方法,综合岩心观察、测井曲线、微量元素特征、沉积构造及古生物化石等资料,对苏里格气田S区块山1段进行系统研究。并结合单井相、沉积相连井剖面及砂地比特征,刻画山1段沉积微相展布特征。研究结果表明,研究区岩性主要为中-细砂岩,总体表现出牵引流的沉积特征,沉积环境为气候较湿润的弱还原-还原的水下沉积环境。岩心上见冲刷面、板状交错层理、平行层理和水平层理等沉积构造,古生物化石以碳化植物茎杆化石或植物叶片化石印模为主。山1段为曲流河三角洲前缘沉积,划分为水下分流河道、水下分流间湾、席状砂沉积微相,主要发育近北南向的水下分流河道砂体,为研究区最主要的储集体。

PD-1单抗治疗对微卫星不稳定型直肠癌免疫微环境的影响

目的:探讨PD-1单抗治疗微卫星不稳定型(MSI-H)直肠癌对患者外周和局部免疫微环境的影响。方法:收集1例MSI-H直肠癌患者PD-1单抗治疗前后外周血及肿瘤活检组织样本,采用酶解法结合机械法解离样本,制备成单细胞悬液。采用单细胞质谱流式技术(CyTOF)检测外周及肿瘤浸润免疫细胞上免疫相关标志物的表达情况。结果:根据CyTOF检测结果,PD-1单抗治疗前后外周血和肿瘤组织中的CD45^(+)免疫细胞分别被分为39个和34个细胞亚群。PD-1单抗治疗后,外周血中B细胞显著减少,肿瘤组织中B细胞、γδT细胞显著富集,中性粒细胞显著减少,T细胞亚群中CD4^(+)TEM细胞占比显著升高,而CD4^(+)Treg细胞则显著减少:在外周血和肿瘤组织中,多种免疫细胞亚群的免疫相关标志物表达存在差异,其中CCR6在各亚群表达显著升高,而ICOS、PD-1等在T细胞亚群中表达则显著降低。结论:PD-1单抗治疗MSI-H直肠癌后,外周血和肿瘤组织中的免疫细胞组成及免疫相关标志物的表达发生变化,免疫微环境发生动态调整,为研究PD-1单抗的治疗机制提供重要依据。

多目标系统化学习的PD-L1切片分析方法

在肿瘤尤其是如肺鳞癌(lung squamous cell carcinoma,LUSC)的非小细胞肺癌的治疗中,基于程序性死亡受体-配体1(programmed cell death-ligand 1,PD-L1)染色切片的阳性肿瘤细胞比例评分(tumor proportion score,TPS)可为治疗方案的选择提供重要依据。肿瘤细胞(tumor cell,TC)的许多参数对癌症诊断至关重要。虽然可以通过计算分析来预测这些参数,但很少有一个统一的框架可以同时获得细胞的不同病理信息。为此,提出了一种多目标学习框架(multi-objective learning pipeline,MOLP),从LUSC的PD-L1切片中预测TPS、细胞数目、细胞核轮廓和类别。主干网络包括两个分支:一个分支通过细胞分析估算TPS,另一个分支直接通过回归分析估算TPS。MOLP通过最小化两个分支的TPS预测差值来提高其鲁棒性。细胞分析支路可实现细胞核分割、分类和计数,不仅增强了TPS估计的可信度,还使得MOLP能够估计肿瘤细胞的外观参数以用于LUSC诊断。在大规模图像集上的实验结果证明了MOLP的可行性和有效性。MOLP预测的TPS与病理医师的评分呈现出统计学上的显著相关性:平均绝对误差仅为4.97(95%置信区间:-0.56~10.49),皮尔逊相关系数为0.97(p<0.001)。

Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude oils.Based on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient sediments.Oil samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter input.It should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

过表达海马LINGO-1对小鼠学习和记忆能力及海马各亚区Spinophilin+树突棘的影响

目的 脑立体定位注射腺相关病毒特异性过表达海马LINGO-1,探讨其对小鼠空间学习和记忆能力以及海马各亚区体积和Spinophilin+树突棘的影响。方法 将7月龄雄性C57小鼠按照简单随机法分为对照组和LINGO-1过表达组,对照组小鼠海马立体定位注射携带绿色荧光的空载腺相关病毒(adeno-associated virus, AAV),LINGO-1过表达组小鼠海马立体定位注射同时携带绿色荧光和LINGO-1过表达载体的AAV。运用Morris水迷宫评估小鼠的空间学习和记忆能力,荧光定量PCR及免疫荧光染色方法分别检测小鼠海马内LINGO-1基因表达水平和各亚区荧光强度,体视学三维定量小鼠海马各亚区体积及Spinophilin+树突棘总数。结果 对照组和LINGO-1过表达组病毒注射前后体质量差异无统计学意义;LINGO-1过表达诱导小鼠海马LINGO-1的mRNA水平升高、荧光强度增强(P<0.01);与对照组相比,LINGO-1过表达组小鼠在Morris水迷宫实验中的表现明显更差(P<0.05);LINGO-1过表达诱导小鼠海马各亚区体积显著下降(P<0.05,P<0.01),Spinophilin+树突棘密度显著降低(P<0.01,P<0.05),Spinophilin+树突棘数量显著减少(P<0.05)。结论 海马立体定位注射过表达LINGO-1腺相关病毒能够特异性上调小鼠海马内LINGO-1水平,海马LINGO-1的异常高表达可导致小鼠海马体积减小及Spinophilin+树突棘突触丢失,并在一定程度上损伤其空间学习与记忆能力。

Physics-embedded machine learning search for Sm-doped PMN-PT piezoelectric ceramics with high performance

Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different concentrations of elemental doping are the main methods to modulate their piezoelectric coefficients.The combination of these controllable conditions leads to an exponential increase of possible compositions in ceramics,which makes it not easy to extend the sample data by additional experimental or theoretical calculations.In this paper,a physics-embedded machine learning method is proposed to overcome the difficulties in obtaining piezoelectric coefficients and Curie temperatures of Sm-doped PMN-PT ceramics with different components.In contrast to all-data-driven model,physics-embedded machine learning is able to learn nonlinear variation rules based on small datasets through potential correlation between ferroelectric properties.Based on the model outputs,the positions of morphotropic phase boundary(MPB)with different Sm doping amounts are explored.We also find the components with the best piezoelectric property and comprehensive performance.Moreover,we set up a database according to the obtained results,through which we can quickly find the optimal components of Sm-doped PMN-PT ceramics according to our specific needs.

基于Keap1/Nrf2/HO-1通路探讨虎杖苷对衰老小鼠学习认知障碍的作用机制

目的研究虎杖苷对D-半乳糖致衰老模型小鼠的调节作用。方法将56只ICR小鼠(雌雄各半)分为正常组、模型组、阳性组、虎杖苷低、中、高治疗组,通过每日颈后部皮下注射D-半乳糖(500 mg·kg^(-1))建立衰老模型。造模期间,阳性组灌胃盐酸多奈哌齐片(0.75 mg·kg^(-1)),治疗组灌胃虎杖苷(40、70、100 mg·kg^(-1)),正常组给予等量生理盐水。通过筑巢实验、新型物体识别实验与Morris水迷宫实验评估小鼠学习认知能力;取小鼠心、肝、脾、肾、胸腺计算脏器指数;苏木精-伊红(HE)染色观察小鼠全脑组织病理变化;ELISA检测小鼠血清与全脑组织中T-SOD、MDA、GSH-Px、AchE水平;Western blot检测小鼠海马组织Keap1、Nrf2、HO-1蛋白表达水平。结果较模型组相比,阳性组与虎杖苷低、中、高剂量组小鼠的筑巢能力、对新物体的识别能力与水下寻找站台的能力有所上升;脏器指数增加;大脑皮层与海马组织的神经元损伤明显改善;血清与脑组织中T-SOD、GSH-Px活性升高,MDA、AchE活性下降;海马组织中Nrf2、HO-1蛋白表达水平上升,Keap1蛋白表达水平降低。结论虎杖苷对D-半乳糖致衰老模型小鼠的学习认知障碍具有改善作用,其机制可能与Keap1/Nrf2/HO-1通路有关。

基于HJ-1 CCD光谱信息的水体识别方法研究——以松花湖为例

该研究利用环境一号卫星(HJ-1)的CCD数据,采用3种不同的水体自动识别方法,即归一化水体指数(NDWI)、近红外阈值法和监督分类法,对2012—2020年间松花湖的水体进行识别和面积计算。该研究旨在评估各方法在水体面积变化检测中的表现及适用性,通过对比这些方法在不同年份的应用效果。结果表明,监督分类法在多数情况下能够识别出更大的水体面积,显示其在广泛水体监测中的优越性。近红外阈值法在特定年份也表现出较好的水体识别效果。该研究结果可以为HJ-1 CCD在水域监测和灾害预防等方面提供重要的决策支持。

王浆主蛋白1(MRJP-1)及其对蜜蜂学习记忆影响的研究进展

蜂王浆由蜜蜂幼年工蜂所产,是蜂王及工蜂小幼虫的唯一食物来源,同时也因蜂王浆的丰富营养价值而为人们所熟知。蜂王浆主蛋白(MRJPs)是蜂王浆中最为丰富的水溶性蛋白,其中的MRJP-1除提供营养外,对蜜蜂的个体发育、神经系统发育、行为调控、级型分化等方面均有很好的生理调节作用。文章介绍了MRJP-1的理化特性和在蜜蜂体内的表达情况,并对MRJP-1在蜜蜂学习记忆方面的影响研究作简要概括,以期为王浆主蛋白在蜜蜂认知行为方面的研究提供一些思路和理论支撑。