Background:Nonalcoholic fatty liver disease(NAFLD)is a chronic condition characterized by a progressive decline in liver function,leading to disruptions in liver integrity and metabolic function,resulting in lipid dep...Background:Nonalcoholic fatty liver disease(NAFLD)is a chronic condition characterized by a progressive decline in liver function,leading to disruptions in liver integrity and metabolic function,resulting in lipid deposition and excessive accumulation of extracellular matrix(ECM).The pathogenesis of NAFLD is complex and not yet fully understood,contributing to the absence of specific therapeutic strategies.Peroxisome proliferator-activated receptor gamma(PPARγ)is a ligand-activated transcription factor pivotal in regulating lipid and glucose metabolism.However,the impacts of PPARγon NAFLD remains insufficiently explored.Thus,this study aimed to investigate the role of PPARγin NAFLD and its underlying molecular mechanisms.Methods:Chemical detection kits were utilized to quantify collagen content,alanine aminotransferase(ALT),and aspartate aminotransferase(AST)level variations.Quantitative real-time polymerase chain reaction(qRT-PCR)was employed to assess alterations in extracellular matrix-related genes and inflammatory response genes in liver tissue and HepG2 cells,while western blotting was conducted to analyze the levels of both PPARγand the TGF-β/Smad signaling pathway.Results:Our findings unveiled significantly reduced PPARγexpression in a rat model of NAFLD,leading to subsequent activation of the TGF-β/Smad signaling pathway.Furthermore,PPARγactivation effectively mitigated NAFLD progression by inhibiting inflammation and fibrosis-related gene expression and collagen production.On a cellular level,PPARγactivation was found to inhibit the expression of extracellular matrix-related genes such as matrix metalloproteinase 2(MMP2)and matrix metalloproteinase 9(MMP9),along with inflammatory response genes interleukin(IL)-1βand IL-6.Additionally,PPARγactivation led to a significant decrease in the levels of ALT and AST.At the molecular level,PPARγnotably down-regulated the TGF-β/Smad signaling pathway,which is known to promote liver fibrosis.Conclusion:These groundbreaking findings underscore PPARγactivation as a promising therapeutic approach to delay NAFLD progression by targeting the TGF-β/Smad signaling pathway in hepatic cells.This highlights the potential of PPARγas a promising therapeutic target for NAFLD management in clinical settings.展开更多
This paper proposes a novel unified visco-plastic constitutive model for uniaxial ratcheting behaviors. The cyclic deformation of the material presents remarkable time-dependence and history memory phenomena. The frac...This paper proposes a novel unified visco-plastic constitutive model for uniaxial ratcheting behaviors. The cyclic deformation of the material presents remarkable time-dependence and history memory phenomena. The fractional(fractional-order)derivative is an efficient tool for modeling these phenomena. Therefore, we develop a cyclic fractional-order unified visco-plastic(FVP) constitutive model. Specifically, within the framework of the cyclic elasto-plastic theory, the fractional derivative is used to describe the accumulated plastic strain rate and nonlinear kinematic hardening rule based on the Ohno-Abdel-Karim model. Moreover, a new radial return method for the back stress is developed to describe the unclosed hysteresis loops of the stress-strain properly.The capacity of the FVP model used to predict the cyclic deformation of the SS304 stainless steel is verified through a comparison with the corresponding experimental data found in the literature(KANG, G. Z., KAN, Q. H., ZHANG, J., and SUN, Y. F. Timedependent ratcheting experiments of SS304 stainless steel. International Journal of Plasticity, 22(5), 858–894(2006)). The FVP model is shown to be successful in predicting the rate-dependent ratcheting behaviors of the SS304 stainless steel.展开更多
Background:Alzheimer's disease(AD)is an incurable and irreversible neurodegen-erative disease,without a clear pathogenesis.Therefore,identification of candidates before amyloid-βplaque(Aβ)deposition proceeds is ...Background:Alzheimer's disease(AD)is an incurable and irreversible neurodegen-erative disease,without a clear pathogenesis.Therefore,identification of candidates before amyloid-βplaque(Aβ)deposition proceeds is of major significance for earlier intervention in AD.Methods:To explore the potential noninvasive earlier biomarkers of AD in a 5XFAD mouse model,microRNAs(miRNAs)from urinary exosomes in 1-month-old pre-Aβaccumulation 5XFAD mice models and their littermate controls were profiled by mi-croarray analysis.The differentially expressed miRNAs were further analyzed via droplet digital PCR(ddPCR).Results:Microarray analysis demonstrated that 48 differentially expressed miRNAs(18 upregulated and 30 downregulated),of which six miRNAs-miR-196b-5p,miR-339-3p,miR-34a-5p,miR-376b-3p,miR-677-5p,and miR-721-were predicted to display gene targets and important signaling pathways closely associated with AD pathogenesis and verified by ddPCR.Conclusions:Urinary exosomal miRNAs showing differences in expression prior to Aβ-plaque deposition were identified.These exosomal miRNAs represent potential noninvasive biomarkers that may be used to prevent AD in clinical applications.展开更多
[Objectives] To observe the clinical therapeutic efficacy of local hot-wet compress therapy of digestion ointment prescription on the patients with moderate and severe mastalgia. [Methods] Firstly,60 patients with mas...[Objectives] To observe the clinical therapeutic efficacy of local hot-wet compress therapy of digestion ointment prescription on the patients with moderate and severe mastalgia. [Methods] Firstly,60 patients with mastalgia were selected,and divided into the experimental group and control group( 30 cases for each group). The control group was treated with acupuncture at distal point,and the experimental group was treated with TCM local hot-wet compress therapy combined with acupuncture at distal point. Then,the clinical therapeutic efficacy of two groups was compared. [Results]The experimental group was superior to the control group in relieving the breast pain,improving emotional integral,reducing breast lumps,improving lump texture,and improving TCM syndrome integral( P < 0. 05). [Conclusions]The digestion ointment prescription local hot-wet compress therapy has a significant therapeutic effect on treatment of mastalgia and can significantly improve the breast pain symptom of patients.展开更多
The sieving and enrichment of rare tumor cells from large-volume pleural effusion(PE)samples is a promising technique for cell-based lung tumor diagnosis and drug tests,which features high throughput and recovery,puri...The sieving and enrichment of rare tumor cells from large-volume pleural effusion(PE)samples is a promising technique for cell-based lung tumor diagnosis and drug tests,which features high throughput and recovery,purification,as well as viability rates of rare target cells as the prerequisites for high sensitivity,specificity,and accuracy of tumor cell analysis.In this paper,we propose a three-dimensional(3 D)sieving method for rare tumor cell enrichment,which effectively eliminates the"dead zones"in traditional two-dimensional(2 D)cell filters with a dimension-raising strategy to satisfy the requirements mentioned above.The prototype device was combined with a funnel-shaped holder,a flexible micropore membrane in the middle,and a3 D spiral fluid channel covered on the membrane as a three-layer ice-creaming cone composite structure.Driven by gravity alone,the device performed as follows:(1)20-fold throughput compared with the 2 D commercial planee hich was up to 20 mL/min for a threefold dilution of whole blood sample;(2)high recovery rates of 84.5%±21%,86%±25%,83%±14%for 100,1000,and 10000 cells/mL,respectively,in 30 mL phosphate buffer saline(PBS)sample,and a 100%positive detection rate in the case of≤5 A549 cells in 1 mL PBS;(3)a typical purification rate of 85.5%±9.1%;and(4)a viability rate of>93%.In the demonstration application,this device effectively enriched rare target cells from large volumes(>25 mL)of clinical pleural effusions.The following results indicated that tumor cells were easy-to-discover in the enriched PE samples,and the proliferation capability of purified cells was(>4.6 times)significantly stronger than that of unprocessed cells in the subsequent 6-day culture.The above evaluation indicates that the proposed easily reproducible method for the effective execution of rare cell enrichments and assays is expected to become a practical technique for clinical cell-based tumor diagnosis.展开更多
The steamed Panax ginseng C. A. Mey., Panax notoginseng(Burk.) F. H. Chen, and Panax quinquefolium L. not only facilitate storage, but also increase the content of rare saponins and enhance their clinical application ...The steamed Panax ginseng C. A. Mey., Panax notoginseng(Burk.) F. H. Chen, and Panax quinquefolium L. not only facilitate storage, but also increase the content of rare saponins and enhance their clinical application value. The traditional steaming process has high energy consumption, low efficiency, and lacks standardized operating procedures and unified standards. This paper retrieves the research literature on the steaming process parameters, rare saponin increments, and efficacy enhancement results of ginseng plants. By summarizing the effects of different steaming processes on rare saponins and pharmacodynamics in P. ginseng, P. notoginseng and P. quinquefolium, we explored new steaming methods and established a new quality evaluation system to provide guarantee for the effectiveness and safety of clinical medication and provide scientific basis for its rational use.展开更多
Evidence suggests associations between COVID-19 patients or vaccines and glycometabolic dysfunction and an even higher risk of the occurrence of diabetes.Herein,we retrospectively analyzed pancreatic lesions in autops...Evidence suggests associations between COVID-19 patients or vaccines and glycometabolic dysfunction and an even higher risk of the occurrence of diabetes.Herein,we retrospectively analyzed pancreatic lesions in autopsy tissues from 67 SARS-CoV-2 infected non-human primates(NHPs)models and 121 vaccinated and infected NHPs from 2020 to 2023 and COVID-19 patients.Multi-label immunofluorescence revealed direct infection of both exocrine and endocrine pancreatic cells by the virus in NHPs and humans.Minor and limited phenotypic and histopathological changes were observed in adult models.Systemic proteomics and metabolomics results indicated metabolic disorders,mainly enriched in insulin resistance pathways,in infected adult NHPs,along with elevated fasting C-peptide and C-peptide/glucose ratio levels.Furthermore,in elder COVID-19 NHPs,SARS-CoV-2 infection causes loss of beta(β)cells and lower expressed-insulin in situ characterized by islet amyloidosis and necrosis,activation ofα-SMA and aggravated fibrosis consisting of lower collagen in serum,an increase of pancreatic inflammation and stress markers,ICAM-1 and G3BP1,along with more severe glycometabolic dysfunction.In contrast,vaccination maintained glucose homeostasis by activating insulin receptorαand insulin receptorβ.Overall,the cumulative risk of diabetes post-COVID-19 is closely tied to age,suggesting more attention should be paid to blood sugar management in elderly COVID-19 patients.展开更多
With the gradual progression of the carbon neutrality target,the future of our electricity supply will experience a massive increase in solar generation,and approximately 50%of the global electricity generation will c...With the gradual progression of the carbon neutrality target,the future of our electricity supply will experience a massive increase in solar generation,and approximately 50%of the global electricity generation will come from solar generation by 2050.This provides the opportunity for researchers to diversify the applications of photovoltaics(PVs)and integrate for daily use in the future.Flexible solar cell technology is the next frontier in solar PV and is the key way to achieve CO_(2)neutrality.The integration of PV technology with other fields will greatly broaden the development areas for the PV industry,providing products with higher added value.In this paper,we reviewed the latest research progress on flexible solar cells(perovskite solar cells,organic solar cells,and flexible silicon solar cells),and proposed the future applications of flexible solar cell technology.展开更多
The scarcity of proxies and calibration models for quantitatively reconstructing millennial timescale seasonal temperature tremendously constraints our understanding of the Holocene thermal variation and its driven me...The scarcity of proxies and calibration models for quantitatively reconstructing millennial timescale seasonal temperature tremendously constraints our understanding of the Holocene thermal variation and its driven mechanisms.Here,we established two global warm-season temperature models by applying deep learning neural network analysis to the branched tetraether membrane lipids originating from surface soil and lacustrine sediment bacteria.We utilized these optimal models in global well-dated lacustrine,peatland,and loess profiles covering the Holocene.All reconstructions of warm-season temperatures,consistent with climate model simulations,indicate cooling trends since the early Holocene,primarily induced by decreased solar radiation in the Northern Hemisphere due to the precession peak at the early.We further demonstrated that the membrane lipids can effectively enhance the future millennial seasonal temperature research,including winter temperatures,without being restricted by geographical location and sedimentary carrier.展开更多
The degradation of organic pollutants using semiconductor photocatalysts is a new ecological approach,but the currently available photocatalysts are not very efficient.Herein,in order to obtain efficient visible-light...The degradation of organic pollutants using semiconductor photocatalysts is a new ecological approach,but the currently available photocatalysts are not very efficient.Herein,in order to obtain efficient visible-light photocatalysts,g-C_(3)N_(4)/β-FeOOH-modified carbon quantum dots(CDs)composite photocat-alysts with Z-Scheme charge transfer mechanism were successfully synthesized.The phase composition and morphology of the composite were characterized by X-ray diffraction(XRD),scanning electron mi-croscopy(SEM),transmission electron microscopy(TEM),Fourier transform infrared spectrophotometry(FT-IR),and X-ray photoelectron spectroscopy(XPS)techniques.Due to the upconversion effect of the CDs,the optical response range of the composite was effectively widened,and the optical utilization rate was improved.The Z-Scheme heterostructure not only improves the light trapping ability,significantly inhibits charge-carrier complexation,and realizes the spatial separation of redox sites,but also ensures that the photocatalyst maintains a suitable valence-conductivity band position and maintains the strong redox reactivity.In addition,CDs have the unique characteristics of electronic storage and transfer,which effectively enhance the quantum separation efficiency of the composite.The photocatalytic efficiency was measured by degrading rhodamine B(RhB)under visible light.The degradation performance was the best when the weight ratio of CDs was 6%,and the RhB solution degradation rate reached 100%in 60 min.The unique structure and reliable mechanism provide a way for the development of advanced photocat-alyst.展开更多
Under the framework of the small deformation crystal plasticity theory,a crystal plastic cyclic constitutive model for body-centered cubic(BCC)cyclic softening polycrystalline metals is established.The constitutive mo...Under the framework of the small deformation crystal plasticity theory,a crystal plastic cyclic constitutive model for body-centered cubic(BCC)cyclic softening polycrystalline metals is established.The constitutive model introduces the isotropic softening rule that includes two different mechanisms:namely softening under monotonic deformation and softening under cyclic deformation on each slip system.Meanwhile,a modified Armstrong-Frederick nonlinear kinematic hardening rule is adopted.The appropriate explicit scale transition rule is selected to extend the single crystal constitutive model to the polycrystalline constitutive model.Then the model is used to predict the uniaxial and multiaxial ratcheting deformation of BCC axle steel EA4T to verify the rationality of the proposed model.The simulation results indicate that the newly established crystal plasticity model can not only describe the cyclic softening characteristics of BCC axle steel EA4T well,but also reasonably describe the evolution laws of uniaxial ratcheting and nonproportional multiaxial ratcheting deformation.Moreover,the established crystal plastic cyclic constitutive model can reasonably predict the ratcheting behavior of BCC single crystal as well.展开更多
The prevalence of cardiovascular diseases(CVDs)has increased markedly as the world population has aged.Long non-coding RNAs(lncRNAs)have been reported as novel regulators in diverse pathophysiological conditions.Here,...The prevalence of cardiovascular diseases(CVDs)has increased markedly as the world population has aged.Long non-coding RNAs(lncRNAs)have been reported as novel regulators in diverse pathophysiological conditions.Here,we performed RNA sequencing(RNA-seq)and observed that the lncRNA Zeb1os1(zinc finger E-box binding homeobox 1,opposite strand 1),which is known as ZEB1-AS1(zinc finger E-box binding homeobox 1 antisense 1)in humans,was upregulated in the aged mice hearts,senescent cardiomyocytes,and human blood from elderly individuals.The human blood ZEB1-AS1 level was positively relevant to human age but negatively relevant to peak E to peak A(E/A).Silencing Zeb1os1 ameliorated diastolic dysfunction and cardiac senescence in aged mice.On the other hand,Zeb1os1 overexpression triggered cardiac dysfunction resembling that observed in aged mice.Mechanistically,we provide compelling evidence that Zeb1os1 interacts with the transient receptor potential mucolipin 1(TRPML1)for ubiquitination(UB)-mediated degradation.This process inhibits lysosomal Ca^(2+)efflux,impairing lysosome function.In addition,the functional domain of Zeb1os1,which contains the key nucleotides responsible for the pro-senescence property of full-length Zeb1os1 in cardiomyocytes.Together,these data suggest that Zeb1os1 is a potential target for ameliorating lysosomal dysfunction and aging-related cardiac impairment.展开更多
A series of high solid content(30 wt%)epoxy resin(EP)composite coatings reinforced with differently sized cubic boron nitride(CBN)particles were fabricated successfully on 304 L stainless steel.Polydopamine(PDA)was us...A series of high solid content(30 wt%)epoxy resin(EP)composite coatings reinforced with differently sized cubic boron nitride(CBN)particles were fabricated successfully on 304 L stainless steel.Polydopamine(PDA)was used to improve the dispersibility of CBN particles in EP.The structural and morphological features of the CBN particles and the composite coatings were characterized by Raman spectroscopy,scanning electron microscopy(SEM),and transmission electron microscopy(TEM).Moreover,a UMT-3 tribometer and surface profiler were used to investigate the tribological behaviors of the as-prepared composite coatings.Electrochemical impedance spectroscopy(EIS)and Tafel analysis were used to investigate the coatings'anti-corrosion performance.The results demonstrated that the CBN fillers could effectively enhance the tribological and anti-corrosion properties of the EP composite coatings.In addition,when the additive proportion of the microsized(5μm)and nanosized(550 nm)CBN particles was 1:1,the tribological property of the EP composite coatings was optimal for dry sliding,which was attributed to the load carrying capability of the microsized CBN particles and the toughening effect of the nanosized CBN particles.However,when the additive proportion of the microsized and nanosized CBN particles was 2:1,the tribology and corrosion resistance performance were optimal in seawater conditions.We ascribed this to the load-carrying capacity of the microparticles,which played a more important role under the seawater lubrication condition,and the more compact structure,which improved the electrolyte barrier ability for the composite coatings.展开更多
Fluorographene,a new alternative to graphene,it not only inherits the 2-dimensional(2D)layered structure and outstanding mechanical properties,but also possesses controllable C-F bonds.It is meaningful to reveal the e...Fluorographene,a new alternative to graphene,it not only inherits the 2-dimensional(2D)layered structure and outstanding mechanical properties,but also possesses controllable C-F bonds.It is meaningful to reveal the evolution processes of the tribological behaviors from graphene to fluorographene.In this work,fluorinated reduced graphene oxide nanosheets(F-rGO)with different degree of fluorination were prepared using direct gas-fluorination and they were added into gas to liquid-8(GTL-8)base oil as lubricant additive to improve the tribological performance.According to the results,the coefficient of friction(COF)reduced by 21%,notably,the wear rate reduced by 87%with the addition of highly fluorinated reduced graphene oxide(HF-rGO)compared with rGO.It was confirmed that more covalent C-F bonds which improved the chemical stability of HF-rGO resisted the detachment of fluorine so the HF-rGO nanosheets showed less damage,as demonstrated via X-ray photoelectron spectroscopy(XPS),Raman spectra,and transmission electron microscopy(TEM).Meanwhile,the ionic liquid(IL)adsorbed on HF-rGO successfully improved the dispersibility of F-rGO in GTL-8 base oil.The investigation of tribofilm by TEM and focused ion beam(FIB)illustrated that IL displayed a synergy to participate in the tribochemical reaction and increased the thickness of tribofilm during the friction process.展开更多
Given that graphene features high electrical conductivity,it is a kind of material with corrosion-promotion activity.This study aimed to inhibit the corrosion-promotion activity of graphene in coatings.Here,we report ...Given that graphene features high electrical conductivity,it is a kind of material with corrosion-promotion activity.This study aimed to inhibit the corrosion-promotion activity of graphene in coatings.Here,we report an exciting application of epoxy matrix(EP)/F-doped reduced graphene oxide(rGO)coatings for the long-term corrosion protection of steel.The synthesized F-doped rGO(FG)did not reduce the utilization of rGO by a wide margin and possessed distinctive electrically insulating nature.The electrical conductivity of rGO was approximately 1500 S/m,whereas those of FG-1,FG-2 and FG-3 were 1.17,5.217×10^−2 and 3.643×10^-11 S/m,respectively.FG and rGO were then dispersed into epoxy coatings.The chemical structures of rGO and FG were investigated by transmission electron microscopy(TEM),scanning probe microscopy(SPM),X-ray photoelectron spectroscopy(XPS),Fourier-transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD).EP/FG coatings exhibited outstanding corrosion protection in comparison with blank EP and EP/rGO coatings mainly because the corrosion-promotion effect of rGO was eliminated.The anticorrosion ability of EP/FG coatingswasimproved with increased F-doped degree of FG.In addition,electrochemical impendance spectroscopy(EIS)results indicated that the Rc values of EP/FG-2 and EP/FG-3 were four orders of magnitude higher than those of EP/rGO in diluent NaCl solution(3.5 wt.%)after immersion for 90 days.展开更多
In the marine environment,the protective coatings face serious corrosion and biofouling problem,lim-itations,and challenges that made self-healing coatings unable to perform both anti-corrosion and anti-biofouling dua...In the marine environment,the protective coatings face serious corrosion and biofouling problem,lim-itations,and challenges that made self-healing coatings unable to perform both anti-corrosion and anti-biofouling dual-function at the same time.Here we constructed the corrosion resistance and anti-biofouling self-healing coating by integrating nano-containers into the coating matrix,the 2-Undecylimidazoline(ULM)acted as a corrosion inhibitor and anti-biofouling dual-functional agent which was loaded on the natural container attapulgite(ATP).To obtain high healing efficiency,a fluidity-driven self-healing silicone oil coating was thickened by fibrous ATP to enhance its stability,which played a key role in the self-healing and long-term corrosion resistance.The self-healing time of ULM@ATP rein-forced oil coating was 4 s at least in the air and up to 30 s in the 1 M HCl solution.Meanwhile,the ULM@ATP can significantly enhance the corrosion resistance of the self-healing coating,with the best effect achieved when the content of ULM@ATP was 5 wt.%.The impedance modulus of ULM@ATP-2 still reached 1.62×10^(8)Ωcm^(2) after 480 immersion in 3.5 wt.%NaCl solution,which is 3 orders of magnitude high than pure Oil coating(2.17×10^(5)Ωcm^(2)).The restructure of the ATP network and the release of ULM could largely inhibit the corrosion of metal.The continuous open circuit potential of the compos-ite coating performed the potentially infinite self-healing capacity.The self-healing performances of the composite coating in strong acid and base solutions exhibited high environmental suitability.This anti-corrosion and anti-biofouling(the surface coverage of adhered chlorella decreased 96.88%)dual-function strategy of self-healing coatings could be also realized by many other porous nano-materials or function modifications.The self-healing performances of the composite coating in strong acid and base solutions exhibited high environmental suitability.This anti-corrosion and anti-biofouling dual-function strategy of self-healing coatings could be also realized by many other porous nano-materials or function modifica-tions.The rapid response self-healing coating possessed anti-biofouling and active self-healing functions and showed wide application under more service environments.展开更多
Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is transmitted on mink farms between minks and humans in many countries.However,the systemic pathological features of SARS-CoV-2-infected minks are mostly unk...Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is transmitted on mink farms between minks and humans in many countries.However,the systemic pathological features of SARS-CoV-2-infected minks are mostly unknown.Here,we demonstrated that minks were largely permissive to SARS-CoV-2,characterized by severe and diffuse alveolar damage,and lasted at least 14 days post inoculation(dpi).We first reported that infected minks displayed multiple organ-system lesions accompanied by an increased inflammatory response and widespread viral distribution in the cardiovascular,hepatobiliary,urinary,endocrine,digestive,and immune systems.The viral protein partially co-localized with activated Mac-2+macrophages throughout the body.Moreover,we first found that the alterations in lipids and metabolites were correlated with the histological lesions in infected minks,especially at 6 dpi,and were similar to that of patients with severe and fatal COVID-19.Particularly,altered metabolic pathways,abnormal digestion,and absorption of vitamins,lipids,cholesterol,steroids,amino acids,and proteins,consistent with hepatic dysfunction,highlight metabolic and immune dysregulation.Enriched kynurenine in infected minks contributed to significant activation of the kynurenine pathway and was related to macrophage activation.Melatonin,which has significant anti-inflammatory and immunomodulating effects,was significantly downregulated at 6 dpi and displayed potential as a targeted medicine.Our data first illustrate systematic analyses of infected minks to recapitulate those observations in severe and fetal COVID-19 patients,delineating a useful animal model to mimic SARS-CoV-2-induced systematic and severe pathophysiological features and provide a reliable tool for the development of effective and targeted treatment strategies,vaccine research,and potential biomarkers.展开更多
Novel two-dimensional(2D)Nb_(2)C nanosheets were successfully prepared through a simple lultrasonic and magnetic stirring treatment from the original accordion-like powder.To further study their water-lubrication prop...Novel two-dimensional(2D)Nb_(2)C nanosheets were successfully prepared through a simple lultrasonic and magnetic stirring treatment from the original accordion-like powder.To further study their water-lubrication properties and deal with common oxidation problems,Nb_(2)C nanosheets with different oxidation degrees were prepared and achieved long-term stability in deionized water.Scanning electron microscope(SEM),transmission electron microscope(TEM),scanning probe microscope(SPM),X-ray powder diffraction(XRD),Raman,and X-ray photoelectron spectrometer(XPS)experiments were utilized to characterize the structure,morphology,and dispersion of Nb_(2)C nanosheets with different degrees of oxidation.The tribological behaviors of Nb_(2)C with different degrees of oxidation as additives for water lubrication were characterized using a UMT-3 friction testing machine.The wear scars formed on the 316 steel surface were measured using three-dimensional(3D)laser scanning confocal microscopy.The tribological results showed that a moderately oxidized Nb_(2)C nanosheet,which owned the composition of Nb_(2)C/Nb_(2)O5/C,displayed excellent tribological performance,with the friction coefficient(COF)decreasing by 90.3%and a decrease in the wear rate by 73.1%compared with pure water.Combining the TEM and Raman spectra,it was shown that Nb_(2)O5 nanoparticles filled in the worn zone,and the layered Nb_(2)C and C were adsorbed into the surface of the friction pair to form a protective lubricating film.This combined action resulted in an excellent lubricating performance.展开更多
The minimum-time path for intercepting a moving target with a prescribed impact angle is studied in the paper.The candidate paths from Pontryagin’s maximum principle are synthesized,so that each candidate is related ...The minimum-time path for intercepting a moving target with a prescribed impact angle is studied in the paper.The candidate paths from Pontryagin’s maximum principle are synthesized,so that each candidate is related to a zero of a real-valued function.It is found that the real-valued functions or their first-order derivatives can be converted to polynomials of at most fourth degree.As a result,each candidate path can be computed within a constant time by embedding a standard polynomial solver into the typical bisection method.The control strategy along the shortest candidate eventually gives rise to the time-optimal guidance law.Finally,the developments of the paper are illustrated and verified by three numerical examples.展开更多
基金This research was funded by the National Natural Science Foundation of China(82273919 to Zhang Y)the HMU Marshal Initiative Funding(HMUMIF-21022 to Zhang Y).
文摘Background:Nonalcoholic fatty liver disease(NAFLD)is a chronic condition characterized by a progressive decline in liver function,leading to disruptions in liver integrity and metabolic function,resulting in lipid deposition and excessive accumulation of extracellular matrix(ECM).The pathogenesis of NAFLD is complex and not yet fully understood,contributing to the absence of specific therapeutic strategies.Peroxisome proliferator-activated receptor gamma(PPARγ)is a ligand-activated transcription factor pivotal in regulating lipid and glucose metabolism.However,the impacts of PPARγon NAFLD remains insufficiently explored.Thus,this study aimed to investigate the role of PPARγin NAFLD and its underlying molecular mechanisms.Methods:Chemical detection kits were utilized to quantify collagen content,alanine aminotransferase(ALT),and aspartate aminotransferase(AST)level variations.Quantitative real-time polymerase chain reaction(qRT-PCR)was employed to assess alterations in extracellular matrix-related genes and inflammatory response genes in liver tissue and HepG2 cells,while western blotting was conducted to analyze the levels of both PPARγand the TGF-β/Smad signaling pathway.Results:Our findings unveiled significantly reduced PPARγexpression in a rat model of NAFLD,leading to subsequent activation of the TGF-β/Smad signaling pathway.Furthermore,PPARγactivation effectively mitigated NAFLD progression by inhibiting inflammation and fibrosis-related gene expression and collagen production.On a cellular level,PPARγactivation was found to inhibit the expression of extracellular matrix-related genes such as matrix metalloproteinase 2(MMP2)and matrix metalloproteinase 9(MMP9),along with inflammatory response genes interleukin(IL)-1βand IL-6.Additionally,PPARγactivation led to a significant decrease in the levels of ALT and AST.At the molecular level,PPARγnotably down-regulated the TGF-β/Smad signaling pathway,which is known to promote liver fibrosis.Conclusion:These groundbreaking findings underscore PPARγactivation as a promising therapeutic approach to delay NAFLD progression by targeting the TGF-β/Smad signaling pathway in hepatic cells.This highlights the potential of PPARγas a promising therapeutic target for NAFLD management in clinical settings.
基金Project supported by the National Natural Science Foundation of China(Nos.11790282,U1534204,and 11472179)the Natural Science Foundation of Hebei Province of China(No.A2016210099)
文摘This paper proposes a novel unified visco-plastic constitutive model for uniaxial ratcheting behaviors. The cyclic deformation of the material presents remarkable time-dependence and history memory phenomena. The fractional(fractional-order)derivative is an efficient tool for modeling these phenomena. Therefore, we develop a cyclic fractional-order unified visco-plastic(FVP) constitutive model. Specifically, within the framework of the cyclic elasto-plastic theory, the fractional derivative is used to describe the accumulated plastic strain rate and nonlinear kinematic hardening rule based on the Ohno-Abdel-Karim model. Moreover, a new radial return method for the back stress is developed to describe the unclosed hysteresis loops of the stress-strain properly.The capacity of the FVP model used to predict the cyclic deformation of the SS304 stainless steel is verified through a comparison with the corresponding experimental data found in the literature(KANG, G. Z., KAN, Q. H., ZHANG, J., and SUN, Y. F. Timedependent ratcheting experiments of SS304 stainless steel. International Journal of Plasticity, 22(5), 858–894(2006)). The FVP model is shown to be successful in predicting the rate-dependent ratcheting behaviors of the SS304 stainless steel.
基金CAMS Innovation Fund for Medical Sciences,Grant/Award Number:2016-12M-2-006 and 2019-I2M-1-003Young Elite Scientists Sponsorship Program by CAST(YESS),Grant/Award Number:2019QNRC001+1 种基金National Natural Science Foundation of China,Grant/Award Number:81901114Fundamental Research Funds for the Central Universities,Grant/Award Number:3332019091。
文摘Background:Alzheimer's disease(AD)is an incurable and irreversible neurodegen-erative disease,without a clear pathogenesis.Therefore,identification of candidates before amyloid-βplaque(Aβ)deposition proceeds is of major significance for earlier intervention in AD.Methods:To explore the potential noninvasive earlier biomarkers of AD in a 5XFAD mouse model,microRNAs(miRNAs)from urinary exosomes in 1-month-old pre-Aβaccumulation 5XFAD mice models and their littermate controls were profiled by mi-croarray analysis.The differentially expressed miRNAs were further analyzed via droplet digital PCR(ddPCR).Results:Microarray analysis demonstrated that 48 differentially expressed miRNAs(18 upregulated and 30 downregulated),of which six miRNAs-miR-196b-5p,miR-339-3p,miR-34a-5p,miR-376b-3p,miR-677-5p,and miR-721-were predicted to display gene targets and important signaling pathways closely associated with AD pathogenesis and verified by ddPCR.Conclusions:Urinary exosomal miRNAs showing differences in expression prior to Aβ-plaque deposition were identified.These exosomal miRNAs represent potential noninvasive biomarkers that may be used to prevent AD in clinical applications.
基金Supported by Basic Scientific Research Project of Beijing University of Chinese Medicine(2015-JYB-XS166)Project of National Natural Science Foundation(3157397)+2 种基金Project of Beijing Natural Science Foundation(7162082)Beijing TCM Science and Technology Development Fund Project(JJ2015-13)Beijing Municipal Health System High-level Health Technology Talents Training Program(2015-3-113)
文摘[Objectives] To observe the clinical therapeutic efficacy of local hot-wet compress therapy of digestion ointment prescription on the patients with moderate and severe mastalgia. [Methods] Firstly,60 patients with mastalgia were selected,and divided into the experimental group and control group( 30 cases for each group). The control group was treated with acupuncture at distal point,and the experimental group was treated with TCM local hot-wet compress therapy combined with acupuncture at distal point. Then,the clinical therapeutic efficacy of two groups was compared. [Results]The experimental group was superior to the control group in relieving the breast pain,improving emotional integral,reducing breast lumps,improving lump texture,and improving TCM syndrome integral( P < 0. 05). [Conclusions]The digestion ointment prescription local hot-wet compress therapy has a significant therapeutic effect on treatment of mastalgia and can significantly improve the breast pain symptom of patients.
基金supported by the National Key Research and Development Program of China(No.2018YFC2001100)the National Natural Science Foundation of China(Nos.61774167 and 61801477)+2 种基金the Instrument Development Program of the Chinese Academy of Sciences,Beijing Municipal Natural Science Foundation(Nos.4192062 and 4182072)Beijing Municipal Administration of Hospitals Incubating Program(No.PX2017050)Youth Innovation Promotion Association of Chinese Academy of Sciences。
文摘The sieving and enrichment of rare tumor cells from large-volume pleural effusion(PE)samples is a promising technique for cell-based lung tumor diagnosis and drug tests,which features high throughput and recovery,purification,as well as viability rates of rare target cells as the prerequisites for high sensitivity,specificity,and accuracy of tumor cell analysis.In this paper,we propose a three-dimensional(3 D)sieving method for rare tumor cell enrichment,which effectively eliminates the"dead zones"in traditional two-dimensional(2 D)cell filters with a dimension-raising strategy to satisfy the requirements mentioned above.The prototype device was combined with a funnel-shaped holder,a flexible micropore membrane in the middle,and a3 D spiral fluid channel covered on the membrane as a three-layer ice-creaming cone composite structure.Driven by gravity alone,the device performed as follows:(1)20-fold throughput compared with the 2 D commercial planee hich was up to 20 mL/min for a threefold dilution of whole blood sample;(2)high recovery rates of 84.5%±21%,86%±25%,83%±14%for 100,1000,and 10000 cells/mL,respectively,in 30 mL phosphate buffer saline(PBS)sample,and a 100%positive detection rate in the case of≤5 A549 cells in 1 mL PBS;(3)a typical purification rate of 85.5%±9.1%;and(4)a viability rate of>93%.In the demonstration application,this device effectively enriched rare target cells from large volumes(>25 mL)of clinical pleural effusions.The following results indicated that tumor cells were easy-to-discover in the enriched PE samples,and the proliferation capability of purified cells was(>4.6 times)significantly stronger than that of unprocessed cells in the subsequent 6-day culture.The above evaluation indicates that the proposed easily reproducible method for the effective execution of rare cell enrichments and assays is expected to become a practical technique for clinical cell-based tumor diagnosis.
基金supported by the Higher Education Discipline Innovation Project (111 Project, D18012)。
文摘The steamed Panax ginseng C. A. Mey., Panax notoginseng(Burk.) F. H. Chen, and Panax quinquefolium L. not only facilitate storage, but also increase the content of rare saponins and enhance their clinical application value. The traditional steaming process has high energy consumption, low efficiency, and lacks standardized operating procedures and unified standards. This paper retrieves the research literature on the steaming process parameters, rare saponin increments, and efficacy enhancement results of ginseng plants. By summarizing the effects of different steaming processes on rare saponins and pharmacodynamics in P. ginseng, P. notoginseng and P. quinquefolium, we explored new steaming methods and established a new quality evaluation system to provide guarantee for the effectiveness and safety of clinical medication and provide scientific basis for its rational use.
基金supported by the Institute of Basic Medical Sciences,the Chinese Academy of Medical Sciences,the Neuroscience Center,the China Human Brain Banking Consortium,the ALS Brain Bank Initiative in China,and Home for Heal and Help for their assistance in this paper.This work was supported by the National Natural Science Foundation of China(82141204,82061138007,82221004,82041008)the National Key Research and Development Project of China(2020YFA0707803)+2 种基金the CAMS Innovation Fund for Medical Sciences(CIFMS)grant(2021-1-I2M-035,2021-1-I2M-034 and 2021-CAMS-JZ002)Bill&Melinda Gates Foundation(INV-006371)Key-Area Research and Development Program of Guangdong Province(2022B1111020005).
文摘Evidence suggests associations between COVID-19 patients or vaccines and glycometabolic dysfunction and an even higher risk of the occurrence of diabetes.Herein,we retrospectively analyzed pancreatic lesions in autopsy tissues from 67 SARS-CoV-2 infected non-human primates(NHPs)models and 121 vaccinated and infected NHPs from 2020 to 2023 and COVID-19 patients.Multi-label immunofluorescence revealed direct infection of both exocrine and endocrine pancreatic cells by the virus in NHPs and humans.Minor and limited phenotypic and histopathological changes were observed in adult models.Systemic proteomics and metabolomics results indicated metabolic disorders,mainly enriched in insulin resistance pathways,in infected adult NHPs,along with elevated fasting C-peptide and C-peptide/glucose ratio levels.Furthermore,in elder COVID-19 NHPs,SARS-CoV-2 infection causes loss of beta(β)cells and lower expressed-insulin in situ characterized by islet amyloidosis and necrosis,activation ofα-SMA and aggravated fibrosis consisting of lower collagen in serum,an increase of pancreatic inflammation and stress markers,ICAM-1 and G3BP1,along with more severe glycometabolic dysfunction.In contrast,vaccination maintained glucose homeostasis by activating insulin receptorαand insulin receptorβ.Overall,the cumulative risk of diabetes post-COVID-19 is closely tied to age,suggesting more attention should be paid to blood sugar management in elderly COVID-19 patients.
基金supported by the National Natural Science Foundation of China(T2322028,62105129,and 62004208)Sichuan Science and Technology Program(2023ZYD0163)+2 种基金the Science and Technology Commission of Shanghai Municipality(22ZR1473200)the Rising-Star Program of the Shanghai 2023 Science and Technology Innovation Action Plan(23QA1411100)the Autonomous Deployment Project of State Key Laboratory of Materials for Integrated Circuits(NKLJC-Z2023ZD01)。
文摘With the gradual progression of the carbon neutrality target,the future of our electricity supply will experience a massive increase in solar generation,and approximately 50%of the global electricity generation will come from solar generation by 2050.This provides the opportunity for researchers to diversify the applications of photovoltaics(PVs)and integrate for daily use in the future.Flexible solar cell technology is the next frontier in solar PV and is the key way to achieve CO_(2)neutrality.The integration of PV technology with other fields will greatly broaden the development areas for the PV industry,providing products with higher added value.In this paper,we reviewed the latest research progress on flexible solar cells(perovskite solar cells,organic solar cells,and flexible silicon solar cells),and proposed the future applications of flexible solar cell technology.
基金supported by the National Natural Science Foundation of China(42230503)。
文摘The scarcity of proxies and calibration models for quantitatively reconstructing millennial timescale seasonal temperature tremendously constraints our understanding of the Holocene thermal variation and its driven mechanisms.Here,we established two global warm-season temperature models by applying deep learning neural network analysis to the branched tetraether membrane lipids originating from surface soil and lacustrine sediment bacteria.We utilized these optimal models in global well-dated lacustrine,peatland,and loess profiles covering the Holocene.All reconstructions of warm-season temperatures,consistent with climate model simulations,indicate cooling trends since the early Holocene,primarily induced by decreased solar radiation in the Northern Hemisphere due to the precession peak at the early.We further demonstrated that the membrane lipids can effectively enhance the future millennial seasonal temperature research,including winter temperatures,without being restricted by geographical location and sedimentary carrier.
基金supported by the National Natural Science Foundation of China(Nos.21667019,22066017).
文摘The degradation of organic pollutants using semiconductor photocatalysts is a new ecological approach,but the currently available photocatalysts are not very efficient.Herein,in order to obtain efficient visible-light photocatalysts,g-C_(3)N_(4)/β-FeOOH-modified carbon quantum dots(CDs)composite photocat-alysts with Z-Scheme charge transfer mechanism were successfully synthesized.The phase composition and morphology of the composite were characterized by X-ray diffraction(XRD),scanning electron mi-croscopy(SEM),transmission electron microscopy(TEM),Fourier transform infrared spectrophotometry(FT-IR),and X-ray photoelectron spectroscopy(XPS)techniques.Due to the upconversion effect of the CDs,the optical response range of the composite was effectively widened,and the optical utilization rate was improved.The Z-Scheme heterostructure not only improves the light trapping ability,significantly inhibits charge-carrier complexation,and realizes the spatial separation of redox sites,but also ensures that the photocatalyst maintains a suitable valence-conductivity band position and maintains the strong redox reactivity.In addition,CDs have the unique characteristics of electronic storage and transfer,which effectively enhance the quantum separation efficiency of the composite.The photocatalytic efficiency was measured by degrading rhodamine B(RhB)under visible light.The degradation performance was the best when the weight ratio of CDs was 6%,and the RhB solution degradation rate reached 100%in 60 min.The unique structure and reliable mechanism provide a way for the development of advanced photocat-alyst.
基金supported by the National Natural Science Foundation of China(Nos.12032017,11790282).
文摘Under the framework of the small deformation crystal plasticity theory,a crystal plastic cyclic constitutive model for body-centered cubic(BCC)cyclic softening polycrystalline metals is established.The constitutive model introduces the isotropic softening rule that includes two different mechanisms:namely softening under monotonic deformation and softening under cyclic deformation on each slip system.Meanwhile,a modified Armstrong-Frederick nonlinear kinematic hardening rule is adopted.The appropriate explicit scale transition rule is selected to extend the single crystal constitutive model to the polycrystalline constitutive model.Then the model is used to predict the uniaxial and multiaxial ratcheting deformation of BCC axle steel EA4T to verify the rationality of the proposed model.The simulation results indicate that the newly established crystal plasticity model can not only describe the cyclic softening characteristics of BCC axle steel EA4T well,but also reasonably describe the evolution laws of uniaxial ratcheting and nonproportional multiaxial ratcheting deformation.Moreover,the established crystal plastic cyclic constitutive model can reasonably predict the ratcheting behavior of BCC single crystal as well.
基金funded by the National Natural Science Foundation of China(82273919,82270396,and U21A20339)the China Postdoctoral Science Foundation(2023T160176)。
文摘The prevalence of cardiovascular diseases(CVDs)has increased markedly as the world population has aged.Long non-coding RNAs(lncRNAs)have been reported as novel regulators in diverse pathophysiological conditions.Here,we performed RNA sequencing(RNA-seq)and observed that the lncRNA Zeb1os1(zinc finger E-box binding homeobox 1,opposite strand 1),which is known as ZEB1-AS1(zinc finger E-box binding homeobox 1 antisense 1)in humans,was upregulated in the aged mice hearts,senescent cardiomyocytes,and human blood from elderly individuals.The human blood ZEB1-AS1 level was positively relevant to human age but negatively relevant to peak E to peak A(E/A).Silencing Zeb1os1 ameliorated diastolic dysfunction and cardiac senescence in aged mice.On the other hand,Zeb1os1 overexpression triggered cardiac dysfunction resembling that observed in aged mice.Mechanistically,we provide compelling evidence that Zeb1os1 interacts with the transient receptor potential mucolipin 1(TRPML1)for ubiquitination(UB)-mediated degradation.This process inhibits lysosomal Ca^(2+)efflux,impairing lysosome function.In addition,the functional domain of Zeb1os1,which contains the key nucleotides responsible for the pro-senescence property of full-length Zeb1os1 in cardiomyocytes.Together,these data suggest that Zeb1os1 is a potential target for ameliorating lysosomal dysfunction and aging-related cardiac impairment.
基金the National Natural Science Foundation of China(No.51775540)Key Research Program of Frontier Sciences of the Chinese Academy of Science(No.QYZDY-SSW-JSC009)the Youth Innovation Promotion Association,CAS(No.2017338)。
文摘A series of high solid content(30 wt%)epoxy resin(EP)composite coatings reinforced with differently sized cubic boron nitride(CBN)particles were fabricated successfully on 304 L stainless steel.Polydopamine(PDA)was used to improve the dispersibility of CBN particles in EP.The structural and morphological features of the CBN particles and the composite coatings were characterized by Raman spectroscopy,scanning electron microscopy(SEM),and transmission electron microscopy(TEM).Moreover,a UMT-3 tribometer and surface profiler were used to investigate the tribological behaviors of the as-prepared composite coatings.Electrochemical impedance spectroscopy(EIS)and Tafel analysis were used to investigate the coatings'anti-corrosion performance.The results demonstrated that the CBN fillers could effectively enhance the tribological and anti-corrosion properties of the EP composite coatings.In addition,when the additive proportion of the microsized(5μm)and nanosized(550 nm)CBN particles was 1:1,the tribological property of the EP composite coatings was optimal for dry sliding,which was attributed to the load carrying capability of the microsized CBN particles and the toughening effect of the nanosized CBN particles.However,when the additive proportion of the microsized and nanosized CBN particles was 2:1,the tribology and corrosion resistance performance were optimal in seawater conditions.We ascribed this to the load-carrying capacity of the microparticles,which played a more important role under the seawater lubrication condition,and the more compact structure,which improved the electrolyte barrier ability for the composite coatings.
基金the National Natural Science Foundation of China(51775540)Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(QYZDY-SSW-JSC009)the Youth Innovation Promotion Association,CAS(2017338).
文摘Fluorographene,a new alternative to graphene,it not only inherits the 2-dimensional(2D)layered structure and outstanding mechanical properties,but also possesses controllable C-F bonds.It is meaningful to reveal the evolution processes of the tribological behaviors from graphene to fluorographene.In this work,fluorinated reduced graphene oxide nanosheets(F-rGO)with different degree of fluorination were prepared using direct gas-fluorination and they were added into gas to liquid-8(GTL-8)base oil as lubricant additive to improve the tribological performance.According to the results,the coefficient of friction(COF)reduced by 21%,notably,the wear rate reduced by 87%with the addition of highly fluorinated reduced graphene oxide(HF-rGO)compared with rGO.It was confirmed that more covalent C-F bonds which improved the chemical stability of HF-rGO resisted the detachment of fluorine so the HF-rGO nanosheets showed less damage,as demonstrated via X-ray photoelectron spectroscopy(XPS),Raman spectra,and transmission electron microscopy(TEM).Meanwhile,the ionic liquid(IL)adsorbed on HF-rGO successfully improved the dispersibility of F-rGO in GTL-8 base oil.The investigation of tribofilm by TEM and focused ion beam(FIB)illustrated that IL displayed a synergy to participate in the tribochemical reaction and increased the thickness of tribofilm during the friction process.
基金This work was financially supported by the National Natural Science Foundation of China(No.51775540)the Youth Innovation Promotion Association,CAS(No.2017338)+1 种基金the Nature Science Foundation of Zhejiang(No.LQ19E030007)the Natural Science Foundation of Ningbo(No.2018A610114).
文摘Given that graphene features high electrical conductivity,it is a kind of material with corrosion-promotion activity.This study aimed to inhibit the corrosion-promotion activity of graphene in coatings.Here,we report an exciting application of epoxy matrix(EP)/F-doped reduced graphene oxide(rGO)coatings for the long-term corrosion protection of steel.The synthesized F-doped rGO(FG)did not reduce the utilization of rGO by a wide margin and possessed distinctive electrically insulating nature.The electrical conductivity of rGO was approximately 1500 S/m,whereas those of FG-1,FG-2 and FG-3 were 1.17,5.217×10^−2 and 3.643×10^-11 S/m,respectively.FG and rGO were then dispersed into epoxy coatings.The chemical structures of rGO and FG were investigated by transmission electron microscopy(TEM),scanning probe microscopy(SPM),X-ray photoelectron spectroscopy(XPS),Fourier-transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD).EP/FG coatings exhibited outstanding corrosion protection in comparison with blank EP and EP/rGO coatings mainly because the corrosion-promotion effect of rGO was eliminated.The anticorrosion ability of EP/FG coatingswasimproved with increased F-doped degree of FG.In addition,electrochemical impendance spectroscopy(EIS)results indicated that the Rc values of EP/FG-2 and EP/FG-3 were four orders of magnitude higher than those of EP/rGO in diluent NaCl solution(3.5 wt.%)after immersion for 90 days.
基金financially supported by the National Natu-ral Science Foundation of China(No.52105230)the Zhejiang Provincial Natural Science Foundation of China(No.LR21E050001)+1 种基金Zhoushan Municipal Science and Technology Research Program(No.2020C12007)Zhejiang Provincial Natural Science Foun-dation of China(No.LQ22E030019).
文摘In the marine environment,the protective coatings face serious corrosion and biofouling problem,lim-itations,and challenges that made self-healing coatings unable to perform both anti-corrosion and anti-biofouling dual-function at the same time.Here we constructed the corrosion resistance and anti-biofouling self-healing coating by integrating nano-containers into the coating matrix,the 2-Undecylimidazoline(ULM)acted as a corrosion inhibitor and anti-biofouling dual-functional agent which was loaded on the natural container attapulgite(ATP).To obtain high healing efficiency,a fluidity-driven self-healing silicone oil coating was thickened by fibrous ATP to enhance its stability,which played a key role in the self-healing and long-term corrosion resistance.The self-healing time of ULM@ATP rein-forced oil coating was 4 s at least in the air and up to 30 s in the 1 M HCl solution.Meanwhile,the ULM@ATP can significantly enhance the corrosion resistance of the self-healing coating,with the best effect achieved when the content of ULM@ATP was 5 wt.%.The impedance modulus of ULM@ATP-2 still reached 1.62×10^(8)Ωcm^(2) after 480 immersion in 3.5 wt.%NaCl solution,which is 3 orders of magnitude high than pure Oil coating(2.17×10^(5)Ωcm^(2)).The restructure of the ATP network and the release of ULM could largely inhibit the corrosion of metal.The continuous open circuit potential of the compos-ite coating performed the potentially infinite self-healing capacity.The self-healing performances of the composite coating in strong acid and base solutions exhibited high environmental suitability.This anti-corrosion and anti-biofouling(the surface coverage of adhered chlorella decreased 96.88%)dual-function strategy of self-healing coatings could be also realized by many other porous nano-materials or function modifications.The self-healing performances of the composite coating in strong acid and base solutions exhibited high environmental suitability.This anti-corrosion and anti-biofouling dual-function strategy of self-healing coatings could be also realized by many other porous nano-materials or function modifica-tions.The rapid response self-healing coating possessed anti-biofouling and active self-healing functions and showed wide application under more service environments.
基金This work was supported by the National Natural Science Foundation of China(Grant No.32070543)the National Key Research and Development Project of China(Grant No.2020YFA0707803 and 2021YFC0863300)the CAMS Innovation Fund for Medical Sciences(CIFMS)grant(2021-1-I2M-035,2021-1-I2M-034).
文摘Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is transmitted on mink farms between minks and humans in many countries.However,the systemic pathological features of SARS-CoV-2-infected minks are mostly unknown.Here,we demonstrated that minks were largely permissive to SARS-CoV-2,characterized by severe and diffuse alveolar damage,and lasted at least 14 days post inoculation(dpi).We first reported that infected minks displayed multiple organ-system lesions accompanied by an increased inflammatory response and widespread viral distribution in the cardiovascular,hepatobiliary,urinary,endocrine,digestive,and immune systems.The viral protein partially co-localized with activated Mac-2+macrophages throughout the body.Moreover,we first found that the alterations in lipids and metabolites were correlated with the histological lesions in infected minks,especially at 6 dpi,and were similar to that of patients with severe and fatal COVID-19.Particularly,altered metabolic pathways,abnormal digestion,and absorption of vitamins,lipids,cholesterol,steroids,amino acids,and proteins,consistent with hepatic dysfunction,highlight metabolic and immune dysregulation.Enriched kynurenine in infected minks contributed to significant activation of the kynurenine pathway and was related to macrophage activation.Melatonin,which has significant anti-inflammatory and immunomodulating effects,was significantly downregulated at 6 dpi and displayed potential as a targeted medicine.Our data first illustrate systematic analyses of infected minks to recapitulate those observations in severe and fetal COVID-19 patients,delineating a useful animal model to mimic SARS-CoV-2-induced systematic and severe pathophysiological features and provide a reliable tool for the development of effective and targeted treatment strategies,vaccine research,and potential biomarkers.
基金the National Natural Science Foundation of China(51775540)Zhejiang Provincial Natural Science Foundation of China(LR21E050001)the Youth Innovation Promotion Association,CAS(2017338).
文摘Novel two-dimensional(2D)Nb_(2)C nanosheets were successfully prepared through a simple lultrasonic and magnetic stirring treatment from the original accordion-like powder.To further study their water-lubrication properties and deal with common oxidation problems,Nb_(2)C nanosheets with different oxidation degrees were prepared and achieved long-term stability in deionized water.Scanning electron microscope(SEM),transmission electron microscope(TEM),scanning probe microscope(SPM),X-ray powder diffraction(XRD),Raman,and X-ray photoelectron spectrometer(XPS)experiments were utilized to characterize the structure,morphology,and dispersion of Nb_(2)C nanosheets with different degrees of oxidation.The tribological behaviors of Nb_(2)C with different degrees of oxidation as additives for water lubrication were characterized using a UMT-3 friction testing machine.The wear scars formed on the 316 steel surface were measured using three-dimensional(3D)laser scanning confocal microscopy.The tribological results showed that a moderately oxidized Nb_(2)C nanosheet,which owned the composition of Nb_(2)C/Nb_(2)O5/C,displayed excellent tribological performance,with the friction coefficient(COF)decreasing by 90.3%and a decrease in the wear rate by 73.1%compared with pure water.Combining the TEM and Raman spectra,it was shown that Nb_(2)O5 nanoparticles filled in the worn zone,and the layered Nb_(2)C and C were adsorbed into the surface of the friction pair to form a protective lubricating film.This combined action resulted in an excellent lubricating performance.
基金supported by the National Natural Science Foundation of China(Nos.61903331,62088101)the Shanghai Aerospace Science and Technology Innovation Fund,China(No.SAST2019-10)。
文摘The minimum-time path for intercepting a moving target with a prescribed impact angle is studied in the paper.The candidate paths from Pontryagin’s maximum principle are synthesized,so that each candidate is related to a zero of a real-valued function.It is found that the real-valued functions or their first-order derivatives can be converted to polynomials of at most fourth degree.As a result,each candidate path can be computed within a constant time by embedding a standard polynomial solver into the typical bisection method.The control strategy along the shortest candidate eventually gives rise to the time-optimal guidance law.Finally,the developments of the paper are illustrated and verified by three numerical examples.
