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Nature-inspired design of droplet-synthesized polymeric nanoelectrode for photoelectrochemical microRNA sensing within single cells

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Science Bulletin 2024年第2期69卷 159-162页

作者： Si-yuan Yu Yi-li liu Zheng li Dechen Jiang Jing-Juan Xu Hong-yuan Chen Wei-Wei Zhao State Key Laboratory of Analytical Chemistry for life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Nanoelectrodes have been shown to be powerful tools for nanoscopic research on single entities,deepening the understanding of heterogeneity and stochastics for single molecules,nanoparticles and cells[1–3].However,despite their importance,current nanoelectrode preparations are highly restrained to flame/electrochemical etching,metal sputtering,electrochemical deposition,etc.[3],resulting in a limited range of materials(mainly gold,platinum and carbon)for potential-resolved detection of redox-active species(Table S1 online).The enrichment of preparation methods to introduce novel materials and mechanisms should prove significant for the development of nanoelectrodes.

关键词： electrode deepening restrained

Temporal changes in mixing effects on litter decay and nitrogen release in a boreal riparian forest in northeastern China

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Journal of Forestry Research 2024年第2期35卷 33-41页

作者： Simin Wang bo liu Rui li Xiaoxin Sun Rong Mao Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang 330045People’s Republic of China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management of Ministry of Education School of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Heilongjiang Sanjiang Plain Wetland Ecosystem Research Station Fuyuan 156500People’s Republic of China

In riparian forests,litter decay provides essential energy and nutrients for both terrestrial and fluvial *** mixing effects(LMEs)are crucial in regulating litter decay and nutrient dynamics,yet how LMEs change over time is unclear in riparian *** this study,leaf litter of three common species(Alnus sibirica *** Turcz,Betula platyphylla Sukaczev,and Betula fruticosa Pall.)were mixed in an equal mass ratio and LMEs were measured for mass and nitrogen(N)remaining in whole litter mixtures over a 3-year period in a boreal riparian forest,northeastern *** were also assessed for component litter mass and N remaining by separating litter mixtures by *** the decay of litter mixtures,antagonistic effects on mass and N remaining were dominant after one and two years of decay,whereas only additive effects were observed after three *** correlated negatively with functional diversity after the first and two years of decay but disappeared after three *** sorting litter mixtures by species,non-additive LMEs on mass and N remaining decreased over incubation ***,non-additive LMEs were more frequent for litter of both *** and *** with lower N concentration than for *** litter with higher N *** results indicate that incubation time is a key determinant of litter mixing effects during decay and highlight that late-stage litter mixture decay may be predicted from single litter decay dynamics in boreal riparian forests.

关键词： Biodiversity litter quality litter mixtures Synergistic effects Functional diversity

Thiazoloisoindigo-based Polymer Semiconductors: Synthesis,Structure-Property Relationship, Charge Carrier Polarity, and Field-Effect Transistor Performance

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Chinese Journal of Polymer Science 2024年第1期42卷 24-31,I0006页

作者： bo-Wen li Miao Xiong Mei-Hua liu Zhi-Gao li Long Sang Zi-Han Xiong Biao Xiao Jian Pei Xiao-bo Wan Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchoolofOptoelectronic Materials&TechnologyJianghan UniversityWuhan430056China Bejing National Laboratoryfor Molecular Sciences the Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Developing new polymeric semiconductors with excellent device performance is essential for organic electronics. Herein, we synthesized two new thiazoloisoindigo(Tz II)-based polymers, namely, P(Tz II-d Th-d Th) and P(Tz II-d Th-d Tz), by copolymerizing thiophene-flanked Tz II with bithiophene and bithiazole, respectively. Owing to the more electron-deficient nature of bithiazole than bithiophene, P(Tz II-d Th-d Tz)possesses deeper LUMO/HOMO levels of-3.45/-5.47 e V than P(Tz II-d Th-d Th)(-3.34/-5.32 e V). The organic field-effect transistor(OFET) devices based on P(Tz II-d Th-d Th) exhibited p-type behaviors with an average hole mobility value as high as 1.43 cm^(2)·V^(-1)·s^(-1), while P(Tz II-d Th-d Tz)showed typical ambipolar characteristics with average hole and electron mobilities of 0.38 and 0.56 cm^(2)·V^(-1)·s^(-1). In addition, we compared the performances of both polymers with other Tz II-based polymers reported in our previous work, and showed that the charge carrier polarity can be manipulated by adjusting the number of the thiophene units between the acceptor unit. As the increase of the number of thiophene rings,charge carrier polarity shifts from electron-dominated ambipolar transport to hole-dominated ambipolar transport and then to unipolar hole transport in OFETs, which provides an effective molecular design strategy for further optimization of polymer OFET performance.

关键词： Field-effect transistor Charge carrier polarity Thiazoloisoindigo

An Imbalanced Data Classification Method Based on Hybrid Resampling and Fine Cost Sensitive Support Vector Machine

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Computers, Materials & Continua 2024年第6期79卷 3977-3999页

作者： bo Zhu Xiaona Jing Lan Qiu Runbo li College of Mechanical and Electrical Engineering Kunming University of Science&TechnologyKunming650500China

When building a classification model,the scenario where the samples of one class are significantly more than those of the other class is called data *** imbalance causes the trained classification model to be in favor of the majority class(usually defined as the negative class),which may do harm to the accuracy of the minority class(usually defined as the positive class),and then lead to poor overall performance of the model.A method called MSHR-FCSSVM for solving imbalanced data classification is proposed in this article,which is based on a new hybrid resampling approach(MSHR)and a new fine cost-sensitive support vector machine(CS-SVM)classifier(FCSSVM).The MSHR measures the separability of each negative sample through its Silhouette value calculated by Mahalanobis distance between samples,based on which,the so-called pseudo-negative samples are screened out to generate new positive samples(over-sampling step)through linear interpolation and are deleted finally(under-sampling step).This approach replaces pseudo-negative samples with generated new positive samples one by one to clear up the inter-class overlap on the borderline,without changing the overall scale of the *** FCSSVM is an improved version of the traditional *** considers influences of both the imbalance of sample number and the class distribution on classification simultaneously,and through finely tuning the class cost weights by using the efficient optimization algorithm based on the physical phenomenon of rime-ice(RIME)algorithm with cross-validation accuracy as the fitness function to accurately adjust the classification *** verify the effectiveness of the proposed method,a series of experiments are carried out based on 20 imbalanced datasets including both mildly and extremely imbalanced *** experimental results show that the MSHR-FCSSVM method performs better than the methods for comparison in most cases,and both the MSHR and the FCSSVM played significan

关键词： Imbalanced data classification Silhouette value Mahalanobis distance RIME algorithm CS-SVM

THE NYSTROM METHOD FOR ELASTIC WAVE SCATTERINGBY UNboUNDED ROUGH SURFACES

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Journal of Computational Mathematics 2024年第5期42卷 1407-1426页

作者： Jianliang li Xiaoli liu bo Zhang Haiwen Zhang Key Laboratory of Computing and Stochastic Mathematics School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China School of Mathematical Sciences Beihang UniversityBeijing 100191China LSEC and Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

We consider a numerical algorithm for the two-dimensional time-harmonic elastic wave scattering by unbounded rough surfaces with Dirichlet boundary condition.A Nystr¨om method is proposed for the scattering problem based on the integral equation *** of the Nystr¨om method is established with convergence rate depending on the smoothness of the rough *** doing so,a crucial role is played by analyzing the singularities of the kernels of the relevant boundary integral *** experiments are presented to demonstrate the effectiveness of the *** subject classification:35P25,45P05.

关键词： Elastic wave scattering Unbounded rough surface Nystrom method

The transgenerational effects of maternal low-protein diet during lactation on offspring

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Journal of Genetics and Genomics 2024年第8期51卷 824-835页

作者： lin-Jian Gu li li Qian-Nan li Ke Xu Wei Yue Jing-Yi Qiao Tie-Gang Meng Ming-Zhe Dong Wen-Long Lei Jia-Ni Guo Zhen-bo Wang Qing-yuan Sun State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute of Laboratory Animal Sciences CAMS&PUMCBeijing 100021China Guangzhou Key Laboratory of Metabolic Diseases and Reproductive Health Guangdong-Hong Kong Metabolism&Reproduction Joint LaboratoryReproductive Medicine CenterGuangdong Second Provincial General HospitalGuangzhouGuangdong 510317China

Environmental factors such as diet and lifestyle can influence the health of both mothers and ***,its transgenerational transmission and underlying mechanisms remain largely ***,using a maternal lactation-period low-protein diet(LPD)mouse model,we show that maternal LPD during lactation causes decreased survival and stunted growth,significantly reduces ovulation and litter size,and alters the gut microbiome in the female LPD-F1 *** transcriptome of LPD-F1 metaphase II(MII)oocytes shows that differentially expressed genes are enriched in female pregnancy and multiple metabolic ***,maternal LPD causes early stunted growth and impairs metabolic health,which is transmitted over two *** methylome alteration of LPD-F1 oocytes can be partly transmitted to the F2 ***,our results reveal that LPD during lactation transgenerationally affects offspring health,probably via oocyte epigenetic changes.

关键词： Lactationdiet Maternal low-proteindiet DNAmethylation Transgenerational effect Oocyte

Human umbilical cord mesenchymal stem cells attenuate diabetic nephropathy through the IGF1R-CHK2-p53 signalling axis in male rats with type 2 diabetes mellitus

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第7期25卷 568-580页

作者： Hao ZHANG Xinshu WANG bo HU Peicheng li Yierfan ABUDUAINI Hongmei ZHAO Ayinaer JIEENSIHAN Xishuang CHEN Shiyu WANG Nuojin GUO Jian yuan Yunhui li Lei li Yuntong YANG Zhongmin liU Zhaosheng TANG Hua WANG Department of Endocrinology Shanghai East HospitalSchool of MedicineTongji UniversityShanghai 200120China Research Center for Translational Medicine Shanghai East HospitalSchool of MedicineTongji UniversityShanghai 200120China Department of Cardiology Shanghai East HospitalSchool of MedicineTongji UniversityShanghai 200120China Department of Biochemistry and Molecular Biology School of MedicineTongji UniversityShanghai 200331China Shanghai Institute of Stem Cell Research and Clinical Translation Shanghai East HospitalShanghai 200120China Ji’an Hospital Shanghai East HospitalJi’an 343000China

diabetes mellitus(DM)is a disease syndrome characterized by chronic hyperglycaemia.A long-term high-glucose environment leads to reactive oxygen species(ROS)production and nuclear DNA *** umbilical cord mesenchymal stem cell(HUcMSC)infusion induces significant antidiabetic effects in type 2 diabetes mellitus(T2DM)***-like growth factor 1(IGF1)receptor(IGF1R)is important in promoting glucose metabolism in diabetes;however,the mechanism by which HUcMSC can treat diabetes through IGF1R and DNA damage repair remains *** this study,a DM rat model was induced with high-fat diet feeding and streptozotocin(STZ)administration and rats were infused four times with *** glucose,interleukin-6(IL-6),IL-10,glomerular basement membrane,and renal function were *** that interacted with IGF1R were determined through coimmunoprecipitation *** expression of IGF1R,phosphorylated checkpoint kinase 2(p-CHK2),and phosphorylated protein 53(p-p53)was examined using immunohistochemistry(IHC)and western blot ***-linked immunosorbent assay(EliSA)was used to determine the serum levels of 8-hydroxydeoxyguanosine(8-OHdG).Flow cytometry experiments were used to detect the surface markers of *** identification of the morphology and phenotype of HUcMSC was performed by way of oil red“O”staining and Alizarin red *** rats exhibited abnormal blood glucose and IL-6/10 levels and renal function changes in the glomerular basement membrane,increased the expression of IGF1 and ***1R interacted with CHK2,and the expression of p-CHK2 was significantly decreased in IGF1R-knockdown *** cisplatin was used to induce DNA damage,the expression of p-CHK2 was higher than that in the IGF1R-knockdown group without cisplatin *** infusion ameliorated abnormalities and preserved kidney structure and function in DM *** expression of IGF1,IGF1R,p-CHK2,and p-p53,and the level of 8-OHdG in the DM group increased sign

关键词： Insulin-like growth factor 1 receptor(IGF1R) Checkpoint kinase 2(CHK2) Protein 53(p53) Diabetes mellitus Human umbilical cord mesenchymal stem cell(HUcMSC) DNA damage repair

Magneto-optical isotope enrichment of potassium-40 with transverse cooling

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Chinese Optics Letters 2024年第7期22卷 1-5页

作者： Shangjin li Zixuan Zeng bo Yan School of Physics Zhejiang UniversityHangzhou 310027China

Isotope shifts among different isotopes can be effectively addressed using narrow-linewidth lasers,facilitating laser isotope separation and achieving significant enrichment at a single *** separation of potassium isotopes,employing optical pumping and magnetic deflection,has proven to be *** further improve the enrichment of ^(40)K,we introduce 2D transverse cooling to minimize the divergence *** this modification,we demonstrate enrichment of ^(40)K,elevating it from 0.012%to 12%–20%.This represents an enrichment increase by three orders of magnitude,surpassing our previous result by one *** method is particularly well-suited for isotope enrichment of elements with extremely low abundance.

关键词： isotope separation potassium isotopes two-dimensional transverse cooling.

AWG-based large dynamic range fiber Bragg grating interrogation system

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Optoelectronics Letters 2024年第3期20卷 129-134页

作者： li Shufeng yuan Pei li Ke li Ting ZHU lianqing Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument Beijing Information Science&Technology UniversityBeijing 100192China Beijing Laboratory of Optical Fiber Sensing and System Beijing Information Science&Technology UniversityBeijing 100016China

Arrayed waveguide gratings(AWGs) are extensively employed in fiber Bragg grating(FBG) interrogation systems due to their compact size, lightweight nature, and excellent interrogation performance. The resolution and total measurement range of AWG-based FBG interrogation systems are constrained by the output properties of AWG. We proposed an AWG-based large dynamic range interrogation system. The temperature dependence of AWG is exploited to achieve continuous interrogation. The test results show that the interrogation system has a dynamic range of 28.67 nm, an interrogation accuracy better than 25 pm, and a wavelength resolution of 6 pm.

关键词： fiber waveguide AWG