查看更多>>摘要：Arch bridges provide significant technical and economic benefits under suitable conditions.In particular,concrete-filled steel tubular(CFST)arch bridges and steel-reinforced concrete(SRC)arch bridges are two types of arch bridges that have gained great economic competitiveness and span growth potential due to advancements in construction technology,engineering materials,and construction equipment over the past 30 years.Under the leadership of the author,two record-breaking arch bridges-that is,the Pingnan Third Bridge(a CFST arch bridge),with a span of 560 m,and the Tian'e Longtan Bridge(an SRC arch bridge),with a span of 600 m-have been built in the past five years,embodying great techno-logical breakthroughs in the construction of these two types of arch bridges.This paper takes these two arch bridges as examples to systematically summarize the latest technological innovations and practices in the construction of CFST arch bridges and SRC arch bridges in China.The technological innovations of CFST arch bridges include cable-stayed fastening-hanging cantilevered assembly methods,new in-tube concrete materials,in-tube concrete pouring techniques,a novel thrust abutment foundation for non-rocky terrain,and measures to reduce the quantity of temporary facilities.The technological innovations of SRC arch bridges involve arch skeleton stiffness selection,the development of encasing concrete mate-rials,encasing concrete pouring,arch rib stress mitigation,and longitudinal reinforcement optimization.To conclude,future research focuses and development directions for these two types of arch bridges are proposed.
查看更多>>摘要：The rail transit in sulfate-rich areas faces the combined effects of stray current and salt corrosion;how-ever,the sulfate ion transport and concrete degradation mechanisms under such conditions are still unclear.To address this issue,novel sulfate transport and mesoscale splitting tests were designed,with a focus on considering the differences between the interfacial transition zone(ITZ)and cement matrix.Under the influence of stray current,the ITZ played a pivotal role in regulating the transport and mechanical failure processes of sulfate attack,while the tortuous and blocking effects of aggregates almost disappeared.This phenomenon was termed the"stray current-induced ITZ effect."The experi-mental data revealed that the difference in sulfate ion transport attributed to the ITZ ranged from 1.90 to 2.31 times,while the difference in splitting strength ranged from 1.56 to 1.64 times.Through the real-time synchronization of splitting experiments and microsecond-responsive particle image velocime-try(PIV)technology,the mechanical properties were exposed to the consequences of the stray current-induced ITZ effect.The number of splitting cracks in the concrete increased,rather than along the central axis,which was significantly different from the conditions without stray current and the ideal Brazilian disk test.Furthermore,a sulfate ion mass transfer model that incorporates reactivity and electrodiffusion was meticulously constructed.The embedded finite element calculation exhibited excellent agreement with the experimental results,indicating its reliability and accuracy.Additionally,the stress field was determined utilizing analytical methods,and the mechanism underlying crack propagation was success-fully obtained.Compared to the cement matrix,a stray current led to more sulfates,more microstructure degradation,and greater increases in thickness and porosity in the ITZ,which was considered to be the essence of the stray current-induced ITZ effect.
查看更多>>摘要：Scientific and technological revolutions and industrial transformations have accelerated the rate of inno-vation in environmental engineering technologies.However,few researchers have evaluated the current status and future trends of technologies.This paper summarizes the current research status in eight major subfields of environmental engineering-water treatment,air pollution control,soil/solid waste management,environmental biotechnology,environmental engineering equipment,emerging contami-nants,synergistic reduction of pollution and carbon emissions,and environmental risk and intelligent management-based on bibliometric analysis and future trends in greenization,low carbonization,and intelligentization.Disruptive technologies are further identified based on discontinuous transformation,and ten such technologies are proposed,covering general and specific fields,technical links,and value sources.Additionally,the background and key innovations in disruptive technologies are elucidated in detail.This study not only provides a scientific basis for strategic decision-making,planning,and imple-mentation in the environmental engineering field but also offers methodological guidance for the research and determination of breakthrough technologies in other areas.
查看更多>>摘要：Microwave absorption(MA)materials are essential for protecting against harmful electromagnetic radi-ation.In this study,highly efficient and ultrawide-band microwave-absorbing fabrics with superhy-drophobic surface features were developed using a facile dip-coating method involving in situ graphene oxide(GO)reduction,deposition of TiO2 nanoparticles,and subsequent coating of a mixture of polydimethylsiloxane(PDMS)and octadecylamine(ODA)on polyester fabrics.Owing to the presence of hierarchically structured surfaces and low-surface-energy materials,the resultant reduced GO(rGO)/TiO2-ODA/PDMS-coated fabrics demonstrate superhydrophobicity with a water contact angle of 159° and sliding angle of 5°.Under the synergistic effects of conduction loss,interface polarization loss,and surface roughness topography,the optimized fabrics show excellent microwave absorbing performances with a minimum reflection loss(RLmin)of-47.4 dB and a maximum effective absorption bandwidth(EABmax)of 7.7 GHz at a small rGO loading of 6.9 wt％.In addition,the rGO/TiO2-ODA/PDMS coating was robust,and the coated fabrics could withstand repeated washing,soiling,long-term ultraviolet irradiation,and chemical attacks without losing their superhydrophobicity and MA properties.Moreover,the coating imparts self-healing properties to the fabrics.This study provides a promising and effective route for the development of robust and flexible materials with microwave-absorbing properties.
查看更多>>摘要：Tubular microfibers have recently attracted extensive interest for applications in tissue engineering.However,the fabrication of tubular fibers with intricate hierarchical structures remains a major chal-lenge.Here,we present a novel one-step microfluidic spinning method to generate bio-inspired screwed conduits(BSCs).Based on the microfluidic rope-coiling effect,a viscous hydrogel precursor is first curved into a helix stream in the channel,and then consecutively packed as a hollow structured stream and gelated into a screwed conduit(SC)via ionic and covalent crosslinking.By taking advantage of the excel-lent fluid-controlling ability of microfluidics,various tubes with diverse structures are fabricated via sim-ple control over fluid velocities and multiple microfluidic device designs.The perfusability and permeability results,as well as the encapsulation and culture of human umbilical vein endothelial cells(HUVECs),human pulmonary alveolar epithelial cells(HPAs),and myogenic cells(C2C12),demonstrate that these SCs have good perfusability and permeability and the ability to induce the formation of func-tional biostructures.These features support the uniqueness and potential applications of these BSCs as biomimetic blood vessels and bronchiole tissues in combination with tissue microstructures,with likely application possibilities in biomedical engineering.
查看更多>>摘要：In ophthalmology,the quality of fundus images is critical for accurate diagnosis,both in clinical practice and in artificial intelligence(AI)-assisted diagnostics.Despite the broad view provided by ultrawide-field(UWF)imaging,pseudocolor images may conceal critical lesions necessary for precise diagnosis.To address this,we introduce UWF-Net,a sophisticated image enhancement algorithm that takes disease characteristics into consideration.Using the Fudan University ultra-wide-field image(FDUWI)dataset,which includes 11 294 Optos pseudocolor and 2415 Zeiss true-color UWF images,each of which is rigor-ously annotated,UWF-Net combines global style modeling with feature-level lesion enhancement.Pathological consistency loss is also applied to maintain fundus feature integrity,significantly improving image quality.Quantitative and qualitative evaluations demonstrated that UWF-Net outperforms exist-ing methods such as contrast limited adaptive histogram equalization(CLAHE)and structure and illumi-nation constrained generative adversarial network(StillGAN),delivering superior retinal image quality,higher quality scores,and preserved feature details after enhancement.In disease classification tasks,images enhanced by UWF-Net showed notable improvements when processed with existing classifica-tion systems over those enhanced by StillGAN,demonstrating a 4.62％increase in sensitivity(SEN)and a 3.97％increase in accuracy(ACC).In a multicenter clinical setting,UWF-Net-enhanced images were pre-ferred by ophthalmologic technicians and doctors,and yielded a significant reduction in diagnostic time((13.17±8.40)s for UWF-Net enhanced images vs(19.54±12.40)s for original images)and an increase in diagnostic accuracy(87.71％for UWF-Net enhanced images vs 80.40％for original images).Our research verifies that UWF-Net markedly improves the quality of UWF imaging,facilitating better clinical outcomes and more reliable AI-assisted disease classification.The clinical integration of UWF-Net holds great promise for enhancing diagnostic processes and patient care in ophthalmology.
查看更多>>摘要：Nonalcoholic steatohepatitis(NASH)may soon become the leading cause of end-stage liver disease world-wide with limited treatment options.Liver fibrosis,which is driven by chronic inflammation and hepatic stellate cell(HSC)activation,critically determines morbidity and mortality in patients with NASH.Pyruvate kinase M2(PKM2)is involved in immune activation and inflammatory liver diseases;however,its role and therapeutic potential in NASH-related fibrosis remain largely unexplored.Bioinformatics screening and analysis of human and murine NASH livers indicated that PKM2 was upregulated in non-parenchymal cells(NPCs),especially macrophages,in the livers of patients with fibrotic NASH.Macrophage-specific PKM2 knockout(PKM2FL/FLLysM-Cre)significantly ameliorated hepatic inflammation and fibrosis severity in three distinct NASH models induced by a methionine-and choline-deficient(MCD)diet,a high-fat high-cholesterol(HFHC)diet,and a western diet plus weekly carbon tetrachloride injection(WD/CCl4).Single-cell transcriptomic analysis indicated that deletion of PKM2 in macrophages reduced profibrotic Ly6Chigh macrophage infiltration.Mechanistically,PKM2-dependent glycolysis pro-moted NLR family pyrin domain containing 3(NLRP3)activation in proinflammatory macrophages,which induced HSC activation and fibrogenesis.A pharmacological PKM2 agonist efficiently attenuated the profi-brotic crosstalk between macrophages and HSCs in vitro and in vivo.Translationally,ablation of PKM2 in NPCs by cholesterol-conjugated heteroduplex oligonucleotides,a novel oligonucleotide drug that preferen-tially accumulates in the liver,dose-dependently reversed NASH-related fibrosis without causing observ-able hepatotoxicity.The present study highlights the pivotal role of macrophage PKM2 in advancing NASH fibrogenesis.Thus,therapeutic modulation of PKM2 in a macrophage-specific or liver-specific manner may serve as a novel strategy to combat NASH-related fibrosis.
Yang SongWei ZhongHarry Cheuk-Hay LauYating Zhang...
204-215页
查看更多>>摘要：Carboxyl ester lipase(CEL),a pivotal enzyme involved in lipid metabolism,is recurrently mutated in obese mice.Here,we aimed to elucidate the functional significance,molecular mechanism,and therapeu-tic potential of CEL in metabolic dysfunction-associated steatohepatitis(MASH).Hepatocyte-specific car-boxyl ester lipase gene(Cel)knockout(Cel△HEP)and wildtype(WT)littermates were fed with choline-deficient high-fat diet(CD-HFD)for 16 weeks,or methionine-and choline-deficient diet(MCD)for three weeks to induce MASH.Liquid chromatography-mass spectrometry and co-immunoprecipitation were employed to identify the downstream targets of CEL.CD-HFD/MCD-fed WT mice received intra-venous injections of CEL-adeno-associated viral,serotype 8(AAV8)to induce specific overexpression of CEL in the liver.We observed a decrease in CEL protein levels in MASH induced by CD-HFD or MCD in mice.Cel△HEP mice fed with CD-HFD or MCD exhibited pronounced hepatic steatosis,inflammation,lipid peroxidation,and liver injury compared to WT littermates,accompanied by increased hepatic nuclear factor kappa-light-chain-enhancer of activated B cell(NF-κB)activation.Consistently,Cel knockdown in mouse primary hepatocytes and AML12 cells aggravated lipid accumulation and inflammation,whereas CEL overexpression exerted the opposite effect.Mechanistically,CEL directly bound to fatty acid synthase(FASN),resulting in reduced FASN SUMOylation,which in turn promoted FASN degradation through the proteasome pathway.Furthermore,inhibition of FASN ameliorated hepatocyte lipid accumu-lation and inflammation induced by Cel knockdown in vivo and in vitro.Hepatocyte-specific CEL overex-pression using AAV8-Cel significantly mitigated steatohepatitis in mice fed with CD-HFD or MCD.CEL protects against steatohepatitis development by directly interacting with FASN and suppressing its expression for de novo lipogenesis.CEL overexpression confers a therapeutic benefit in steatohepatitis.
查看更多>>摘要：In situ regeneration is a promising strategy for constructing tissue engineering heart valves(TEHVs).Currently,the decellularized heart valve(DHV)is extensively employed as a TEHV scaffold.Nevertheless,DHV exhibits limited blood compatibility and notable difficulties in endothelialization,resulting in thrombosis and graft failure.The red blood cell membrane(RBCM)exhibits excellent biocom-patibility and prolonged circulation stability and is extensively applied in the camouflage of nanoparticles for drug delivery;however,there is no report on its application for large-scale modification of decellular-ized extracellular matrix(ECM).For the first time,we utilized a layer-by-layer assembling strategy to immobilize RBCM on the surface of DHV and construct an innovative TEHV scaffold.Our findings demon-strated that the scaffold significantly improved the hemocompatibility of DHV by effectively preventing plasma protein adsorption,activated platelet adhesion,and erythrocyte aggregation,and induced macro-phage polarization toward the M2 phenotype in vitro.Moreover,RBCM modification significantly enhanced the mechanical properties and enzymatic stability of DHV.The rat models of subcutaneous embedding and abdominal aorta implantation showed that the scaffold regulated the polarization of macrophages into the anti-inflammatory and pro-modeling M2 phenotype and promoted endothelializa-tion and ECM remodeling in the early stage without thrombosis and calcification.The novel TEHV exhi-bits excellent performance and can overcome the limitations of commonly used clinical prostheses.
查看更多>>摘要：Gravimetric resonant-inspired biosensors have attracted increasing attention in industrial and point-of-care applications,enabling label-free detection of biomarkers such as DNA and antibodies.Capacitive micromachined ultrasonic transducers(CMUTs)are promising tools for developing miniaturized high-performance biosensing complementary metal-oxide-silicon(CMOS)platforms.However,their oper-ability is limited by inefficient functionalization,aggregation,crosstalk in the buffer,and the requirement for an external high-voltage(HV)power supply.In this study,we aimed to propose a CMUTs-based res-onant biosensor integrated with a CMOS front-end interface coupled with ethylene-glycol alkanethiols to detect single-stranded DNA oligonucleotides with large specificity.The topography of the functional-ized surface was characterized by energy-dispersive X-ray microanalysis.Improved selectivity for on-chip hybridization was demonstrated by comparing complementary and non-complementary single-stranded DNA oligonucleotides using fluorescence imaging technology.The sensor array was further characterized using a five-element lumped equivalent model.The 4 mm2 application-specific integrated circuit chip was designed and developed through 0.18 pm HV bipolar-CMOS-double diffused metal-oxide-silicon(DMOS)technology(BCD)to generate on-chip 20 V HV boosting and to track feedback frequency under a standard 1.8 V supply,with a total power consumption of 3.8 mW in a continuous mode.The measured results indicated a detection sensitivity of 7.943 × 10-3 pmol·L-1·Hz-1 over a concentration range of 1 to 100 μmol·L-1.In conclusion,the label-free biosensing of DNA under dry conditions was successfully demonstrated using a microfabricated CMUT array with a 2 MHz frequency on CMOS electronics with an internal HV supplier.Moreover,ethylene-glycol alkanethiols successfully deposited self-assembled monolayers on aluminum electrodes,which has never been attempted thus far on CMUTs,to enhance the selectivity of bio-functionalization.The findings of this study indicate the possibility of full-on-chip DNA biosensing with CMUTs.
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