Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse prognosis.While numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical myelopathy.This study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic characteristics.Enrichment analysis identified 128 differentially expressed genes that were enriched in patients with neurological disabilities.Using least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,respectively.Signatures of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%accuracy.Our results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

The Anti-Penetration Performance and Mechanism of Metal Materials:A Review

This article reviews the anti-penetration principles and strengthening mechanisms of metal materials,ranging from macroscopic failure modes to microscopic structural characteristics,and further summarizes the micro-macro correlation in the anti-penetration process.Finally,it outlines the constitutive models and numerical simulation studies utilized in the field of impact and penetration.From the macro perspective,nine frequent penetration failure modes of metal materials are summarized,with a focus on the analysis of the cratering,compression shear,penetration,and plugging stages of the penetration process.The reasons for the formation of adiabatic shear bands(ASBs)in metal materials with different crystal structures are elaborated,and the formation mechanism of the equiaxed grains in the ASB is explored.Both the strength and the toughness of metal materials are related to the materials’crystal structures and microstructures.The toughness is mainly influenced by the deformation mechanism,while the strength is explained by the strengthening mechanism.Therefore,the mechanical properties of metal materials depend on their microstructures,which are subject to the manufacturing process and material composition.Regarding numerical simulation,the advantages and disadvantages of different constitutive models and simulation methods are summarized based on the application characteristics of metal materials in high-speed penetration practice.In summary,this article provides a systematic overview of the macroscopic and microscopic characteristics of metal materials,along with their mechanisms and correlation during the anti-penetration and impact-resistance processes,thereby making an important contribution to the scientific understanding of anti-penetration performance and its optimization in metal materials.

固载过氧化氢酶微球清除家庭漂白后残留过氧化氢的研究

利用仿生矿化法制备了固载过氧化氢酶的碳酸钙微球,研究了该载酶微球的包封情况、在苛刻环境中的稳定性和清除漂白纱布后残留过氧化氢的效果。结果表明,该载酶微球粒径约11μm,孔径为5.53 nm,能有效封装住过氧化氢酶;在过氧化氢酶质量浓度为0.15 mg/m L的条件下,该微球对过氧化氢酶具有最高负载量为24.26 mg/g,此时酶包封率为98%,酶活力保留率为72%。该载酶微球与游离酶相比提升了热稳定性(80℃条件下仍能保留38.99%的相对酶活力)、改变了过氧化氢酶对不同pH环境耐受能力的趋势(最适酶活力pH值由pH 8偏移至pH 11),提升了耐表面活性剂性质(在十二烷基硫酸钠环境中仍保留了85.82%的相对酶活力)。且该载酶微球能在25 min完全清除漂白纱布后残留的过氧化氢。

A preliminary investigation on genetic diversity of Sousa chinensis in the Pearl River Estuary and Xiamen of Chinese waters

In this study, the mitochondrial DNA （mtDNA） control region and the mitochondrial cytochrome b gene of stranded Indo-Pacific humpback dolphin （Sousa chinensis） samples from the Pearl River Estuary and Xiamen waters were sequenced and analyzed. The result of mtDNA control region revealed 34 variable sites and four unique haplotypes （named as A, B, C and D） identified among the total samples from these two water areas, and the most common haplotype （A） was shared by 75% of the dolphins sampled from the two water areas. The haplotypic diversity （h） was 0.455 and the nucleodde diversity （π） was 0.0088. The phylogenetic analysis showed that the haplotype A, C, and D were closely related, but the haplotype B （unique for XM01 from Xiamen） was far from the other three. By scanning cytochrome b fragments, two haplotypes （A and B） were identified in these two water areas, and the most common haplotype （A） was shared by 91.67% individuals, while XM01 from Xiamen as the only exception. The data suggest that there is a possibility of gene exchange between the two populations in the Pearl River Estuary and Xiamen waters, and there possibly exists a unique maternal lineage in Xiamen waters.

Molten salt electrochemical modulation of Ni/Co nanoparticles onto N-doped carbon for oxygen reduction

Activation of oxygen over non-precious materials has been an imperative task to develop efficient electrochemical energy storage and conversion such as fuel cells and metal-air batteries.Herein,a molten salt electrochemical modulation of metal-nitrogen-carbon based compounds(M–N–C)is achieved.By electrochemical treatment of polydopamine-coated NiCo_(2)O_(4)(NiCo_(2)O_(4)@PDA)in molten Li_(2)CO_(3)-Na_(2)CO_(3)-K_(2)CO_(3)at 500℃,Ni/Co bimetal-nitrogen-carbon catalyst(denoted as Ni/Co@NC)consisting of Ni-Co nanoparticles anchoring on porous nitrogen-doped carbon is constructed and evaluated as electrocatalysts towards the oxygen reduction reaction(ORR).Experimental and calculation results confirm that alloying of Ni-Co and nitrogen doping to carbon enhances the rate-determining transformation of*OH intermediate during ORR.The Ni/Co@NC hence shows an ORR activity comparable with the commercial Pt/C.

Appraising the causal effects of circulating micronutrients on liver cirrhosis:Evidence from large-scale Mendelian randomization analysis

Aims:Observational research has identified links between micronutrient levels and chronic liver disease.However,the lack of randomized controlled experiments has impeded the ability to establish a cause-and-effect connection regarding micronutrients and cirrhosis of the liver.This Mendelian randomization(MR)analysis aimed to examine the causal impact of micronutrients on liver cirrhosis.Methods:We selected genetic instrumental variables related to 12 micronutrients from genome-wide studies on individuals of European descent,covering an array of over 9,851,867 single nucleotide polymorphisms and 460,351 participants.Data from patients with cirrhosis in the FinnGen database(https://www.finngen.fi/fi)were used.A two-sample MR approach was employed to establish genetically causal estimates.Primary analyses used random effects and inverse variance weighted(IVW)methods,with additional sensitivity analyses for validation.MR–Egger intercept analysis and Cochran's Q test assessed horizontal pleiotropy and heterogeneity.Furthermore,multivariable Mendelian randomization(MVMR)was conducted to address potential confounding variables.Results:IVW and weighted median methods showed that most micronutrients included were not significantly associated with a genetic susceptibility to liver cirrhosis.However,MR analysis demonstrated a significant association between circulating vitamin D levels and a reduced risk of liver cirrhosis(odds ratio IVW=0.53,p<0.010).TheMR–Egger intercept showed no evidence of horizontal pleiotropy(p=0.178),whereas Cochran's Q test found no heterogeneity(p=0.799).Furthermore,MVMR analysis confirmed vitamin D was identified as a factor that independently mitigates the risk of liver cirrhosis.Conclusion:This research constitutes the most comprehensive MR investigation in this field,providing evidence supporting a protective link between circulating vitamin D levels and cirrhosis incidence.It suggests that maintaining sufficient vitamin D could be a cost-effective strategy for early intervention in liver cirrhosis.

基础教育适应性学习需求分析与学科应用设计

新技术的持续发展催生了新型学习空间的建设,在此过程中对于适应性学习的认知与需求也相应地发生着深刻变化,并影响着各类面向基础教育阶段的学习产品的研发与应用。在教学实践过程中对适应性学习产品的应用一直停留在对其表层功能的使用上,未发挥出其特有的“适应性”。究其原因,是未理解教学层面适应性学习的意义。本研究通过梳理适应性学习系统的发展脉络,剖析适应性学习的内涵,同时结合对目前基础教育阶段适应性学习产品的分析,以及应用相关产品指导教学实践的具体体验,提取了适应性学习的关键特征。然后从适应性学习系统的功能特征出发,提出了引导学生确立学习目标、进行学习活动序列选择、分析诊断与评价学习行为、适时提供资源与策略指导、形成学习路径与知识体系、激发学习动力与需求的学科应用思路,并以实例说明具体学习活动设计过程。

氧化石墨烯对红细胞功能的影响

纳米材料的生物相容性是人们关注的热点。氧化石墨烯是一种被广泛应用于生物医学的纳米材料,但其毒性不容忽视。本文从溶血率、红细胞脆性、乙酰胆碱酯酶活性三方面研究了氧化石墨烯对血液系统的毒性。结果表明,红细胞的溶血率在氧化石墨烯浓度低于100μg/mL时均低于8%(P<0.01);低浓度氧化石墨烯(<5μg/mL)对红细胞的脆性没有显著影响,高浓度氧化石墨烯(如10μg/mL)会提高红细胞的脆性(P=0.01);氧化石墨烯能增加红细胞上乙酰胆碱酯酶的活性,浓度为20μg/mL的直径>5μm的氧化石墨烯(LGO)可将乙酰胆碱酯酶的活性提高42.67%(P<0.05)。之后利用分子动力学模拟研究氧化石墨烯与乙酰胆碱酯酶相互作用并提高其活性的机理,推测氧化石墨烯会附着在细胞膜上并提供一个电负性环境,帮助水解产物更快地从活性位点脱离,从而提高乙酰胆碱酯酶的活性。

An all-silk-derived functional nanosphere matrix for sequential biomolecule delivery and in situ osteochondral regeneration

Endogenous repair of osteochondral defect is usually limited by the insufficient number of cells in the early stage and incomplete cell differentiation in the later stage.The development of drug delivery systems for sequential release of pro-migratory and pro-chondrogenic molecules to induce endogenous bone marrow-derived mesenchymal stem cells(BMSCs)recruitment and chondrogenic differentiation is highly desirable for in situ osteochondral regeneration.In this study,a novel,all-silk-derived sequential delivery system was fabricated by incorporating the tunable drug-loaded silk fibroin(SF)nanospheres into a SF porous matrix.The loading efficiency and release kinetics of biomolecules depended on the initial SF/polyvinyl alcohol(PVA)concentrations(0.2%,1%and 5%)of the nanospheres,as well as the hydrophobicity of the loaded molecules,resulting in controllable and programmed delivery profiles.Our findings indicated that the 5%nanosphere-incorporated matrix showed a rapid release of E7 peptide during the first 120 h,whereas the 0.2%nanosphere-incorporated matrix provided a slow and sustained release of Kartogenin(KGN)longer than 30 days.During in vitro culture of BMSCs,this functional SF matrix incorporated with E7/KGN nanospheres showed good biocompatibility,as well as enhanced BMSCs migration and chondrogenic differentiation through the release of E7 and KGN.Furthermore,when implanted into rabbit osteochondral defect,the SF nanosphere matrix with sequential E7/KGN release promoted the regeneration of both cartilage and subchondral bone.This work not only provided a novel all-silk-derived drug delivery system for sequential release of molecules,but also a functional tissueengineered scaffold for osteochondral regeneration.

Silk-based hydrogel incorporated with metal-organic framework nanozymes for enhanced osteochondral regeneration

Osteochondral defects(OCD)cannot be efficiently repaired due to the unique physical architecture and the pathological microenvironment including enhanced oxidative stress and inflammation.Conventional strategies,such as the control of implant microstructure or the introduction of growth factors,have limited functions failing to manage these complex environments.Here we developed a multifunctional silk-based hydrogel incorporated with metal-organic framework nanozymes(CuTA@SF)to provide a suitable microenvironment for enhanced OCD regeneration.The incorporation of CuTA nanozymes endowed the SF hydrogel with a uniform microstructure and elevated hydrophilicity.In vitro cultivation of mesenchymal stem cells(MSCs)and chondrocytes showed that CuTA@SF hydrogel accelerated cell proliferation and enhanced cell viability,as well as had antioxidant and antibacterial properties.Under the inflammatory environment with the stimulation of IL-1β,CuTA@SF hydrogel still possessed the potential to promote MSC osteogenesis and deposition of cartilage-specific extracellular matrix(ECM).The proteomics analysis further confirmed that CuTA@SF hydrogel promoted cell proliferation and ECM synthesis.In the full-thickness OCD model of rabbit,CuTA@SF hydrogel displayed successfully in situ OCD regeneration,as evidenced by micro-CT,histology(HE,S/O,and toluidine blue staining)and immunohistochemistry(Col I and aggrecan immunostaining).Therefore,CuTA@SF hydrogel is a promising biomaterial targeted at the regeneration of OCD.

Polydopamine/polyethyleneimine co-crosslinked graphene oxide for the enhanced tribological performance of epoxy resin coatings

To enhance the wear resistance of graphene oxide(GO)nano-filled epoxy resin(EP)coatings with ex-cellent dispersion,GO were modified using a co-crosslinking strategy between polydopamine(PDA)and polyethyleneimine(PEI)through an environmentally friendly,simple and low-cost process.High-density amino-branched PEI and highly adhesive PDA formed covalent bond cross-links with GO(PDA/PEI-GO)through the Michael addition and Schiffbase reactions.With the introduction of amino active sites,the PDA self-polymerization reaction time was significantly shorted from 24 to 6 h.The covalently cross-linked network increased the lamellar spacing of GO and enhanced the interfacial bonds between the PDA/PEI-GO lamellae and EP matrix.Due to the improved dispersion and surface activity of GO,the PDA/PEI-GO nano-filled EP coating exhibited excellent wear resistance.Reciprocating friction with GCr15 stainless steel ball,the average friction coefficient and wear rate of the coating were reduced by 31.9%and 62.7%,respectively,compared to the pure EP coating.In addition,the wear mechanism of the PDA/PEI-GO/EP coating changed from adhesive and fatigue wear to abrasive wear,and it maintained good wear resistance by forming a GO lubrication transfer film on the counterpart surface.Therefore,this study may provide a new strategy for improving the dispersion of graphene in wear-resistant polymer materials for practical applications.

Maximum production point tracking method for a solar-boosted biogas energy generation system

Low biogas yield in cold climates has brought great challenges in terms of the flexibility and resilience of biogas energy systems. This paper proposes a maximum production point tracking method for a solar-boosted biogas generation system to enhance the biogas production rate in extreme climates. In the proposed method, a multi-dimensional R–C thermal circuit model is formulated to analyze the digesting thermodynamic effect of the anaerobic digester with solar energy injection, while a hydrodynamic model is formulated to express the fluid dynamic interaction between the hot-water circulation flow and solar energy injection. This comprehensive dynamic model can provide an essential basis for controlling the solar energy for digester heating to optimize anaerobic fermentation and biogas production efficiency in extreme climates. A model predictive control method is developed to accurately track the maximum biogas production rate in varying ambient climate conditions. Comparative results demonstrate that the proposed methodology can effectively control the fermentation temperature and biogas yield in extreme climates, and confirm its capability to enhance the flexibility and resilience of the solar-boosted biogas generation system.

A study of the lipid-mediated dimerization of the RAGE TM+JM domains by molecular dynamic simulations

Receptor for Advanced Glycation End-products(RAGE) binds to a number of ligand families to display important roles in hyperglycemia, senescence, inflammation, neurodegeneration and cancer. It is reported that RAGE regulates the related biological processes via homo-dimerization by the transmembrane(TM) domain, and evidence further shows that the intracellular domain of RAGE has an influence on the dimerization activity of RAGE. In this study, we explored the underlying interaction mechanism of RAGE TM domains by multiscale coarse-grained(CG) dynamic simulations. Two switching packing modes of the TM dimeric conformations were observed. Through a series of site-directed mutations, we further emphasized the key roles of the A342xxxG346xxG349xxxT353xxL356xxxV360motif in the left-handed configuration and the L345xxxG349xxG352xxxL356motif in the right-handed configuration. In addition, we revealed that the juxtamembrane(JM) domain within JM-A375 can determine the RAGE TM dimeric structure. Overall, we provide the molecular insights into the switching dimerization of RAGE TM domains, as well as the regulation from the JM domains mediated by the anionic lipids.

Negative refraction of ultra-squeezed in-plane hyperbolic designer polaritons

The in-plane negative refraction of high-momentum(i.e.,high-k)photonic modes could enable many applications such as imaging,focusing,and waveguiding in a planar platform at deep-subwavelength scales.However,its practical implementation in experiments remains elusive so far.Here we propose a class of hyperbolic metasurfaces,which is characterized by an anisotropic magnetic sheet conductivity and can support the in-plane ultrahigh-k magnetic designer polaritons.Based on such metasurfaces,we report the experimental observation of the all-angle negative refraction of designer polaritons at extremely deep-subwavelength scales.Moreover,we directly visualize the designer polaritons with hyperbolic dispersions.Importantly,for these hyperbolic polaritons,we find that their squeezing factor is ultra-large.To be specific,it can be up to 129 in the experiments,an ultra-high value exceeding those in naturally hyperbolic materials.This work may pave a way toward exploring the extremely high confinement and unusual propagation of magnetic designer polaritons over monolayer or twisted bilayer hyperbolic metasurfaces.