Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide ...Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide technology for good and prevent and control technological risks has become an important issue of global concern.Research on science and technology ethics is dedicated to integrating ethical theories into governance practices and constructing ethical models that adapt to the development of the times.Methods:This article systematically reviews the six core approaches of scientific and technological ethics thought,including technological autonomy and political philosophy criticism,responsibility ethics and intergenerational obligations,technological intermediation and the integration of life and the world,ethical principles and normative frameworks,participatory governance and ethical practice innovation,as well as domain-specific ethical norms,thereby constructing an ethical analysis framework applicable to medical technology risks.And cross-analysis was conducted by taking medical events such as gene editing and xenotransplantation as examples.Results:Research shows that a single ethical approach has limitations in addressing complex medical ethical challenges,while the six approaches are complementary and synergistic.By criticizing technological autonomy,establishing a responsibility ethics orientation,setting the bottom line of ethical principles,promoting participatory governance,formulating domain norms,and continuously reflecting on the intermediary nature of technology,a multi-level and dynamically adaptive governance system for scientific and technological ethics can be constructed.Conclusion:The key to addressing contemporary medical ethics challenges lies in the comprehensive application of science and technology ethics theories and the integration of ethical considerations throughout the entire process of scientific and technological research and development.In the future,a governance framework that adapts to the development of new technologies should be established to promote cross-cultural and cross-disciplinary ethical dialogue and public participation,ensuring that scientific and technological innovation always serves the dignity of human life and overall well-being.展开更多
Genome-wide association studies(GWASs) are the most widely used method to identify genetic risk loci associated with orofacial clefts(OFC). However, despite the increasing size of cohort, GWASs are still insufficient ...Genome-wide association studies(GWASs) are the most widely used method to identify genetic risk loci associated with orofacial clefts(OFC). However, despite the increasing size of cohort, GWASs are still insufficient to detect all the heritability,suggesting there are more associations under the current stringent statistical threshold. In this study, we obtained an integrated epigenomic dataset based on the chromatin conformation of a human oral epithelial cell line(HIOEC) using RNA-seq, ATAC-seq,H3K27ac Ch IP-seq, and DLO Hi-C. Presumably, this epigenomic dataset could reveal the missing functional variants located in the oral epithelial cell active enhancers/promoters along with their risk target genes, despite relatively less-stringent statistical association with OFC. Taken a non-syndromic cleft palate only(NSCPO) GWAS data of the Chinese Han population as an example, 3664 SNPs that cannot reach the strict significance threshold were subjected to this functional identification pipeline.In total, 254 potential risk SNPs residing in active cis-regulatory elements interacting with 1 718 promoters of oral epitheliumexpressed genes were screened. Gapped k-mer machine learning based on enhancers interacting with epithelium-expressed genes along with in vivo and in vitro reporter assays were employed as functional validation. Among all the potential SNPs, we chose and confirmed that the risk alleles of rs560789 and rs174570 reduced the epithelial-specific enhancer activity by preventing the binding of transcription factors related to epithelial development. In summary, we established chromatin conformation datasets of human oral epithelial cells and provided a framework for testing and understanding how regulatory variants impart risk for clefts.展开更多
Hydrogen displays the potential to partially replace pulverized coal injection(PCI)in the blast furnace,and it can reduce CO_(2)emissions.In this paper,a three-dimensional mathematical model of hydrogen and pulverized...Hydrogen displays the potential to partially replace pulverized coal injection(PCI)in the blast furnace,and it can reduce CO_(2)emissions.In this paper,a three-dimensional mathematical model of hydrogen and pulverized coal co-injection in blast furnace tuyere was established through numerical simulation,and the effect of hydrogen injection and oxygen enrichment interaction on pulverized coal combustion and raceway smelting was investigated.The simulation results indicate that when the coal injection rate decreased from 36 to 30t/h and the hydrogen injection increased from 0 to 3600 m^(3)/h,the CO_(2)emissions decreased from 1860 to 1551 kg/t,which represents a16.6%reduction,and the pulverized coal burnout decreased from 70.1%to 63.7%.The heat released from hydrogen combustion can not only promote the volatilization of pulverized coal but also affect the combustion reaction between volatilization and oxygen,which resulted in a decrease in the temperature at the end of the raceway.Co-injection of hydrogen with PCI increased the wall temperature near the upper half part of the raceway and at the outlet of the tuyere,which required a high cooling efficiency to extend the service life of the blast furnace.The increase in oxygen level compensated for the decreased average temperature in the raceway due to hydrogen injection.The increase in the oxygen content by 3%while maintaining constant hydrogen and PCI injection rates increased the burnout and average raceway temperature by 4.2%and 43 K,respectively.The mole fraction of CO and H_(2) production increased by 0.04 and 0.02,respectively.Burnout can be improved through optimization of the particle size distribution of pulverized coal.展开更多
Inbreeding increases genome homozygosity within populations,which can exacerbate inbreeding depression by exposing homozygous deleterious alleles that are responsible for declines in fitness traits.In small population...Inbreeding increases genome homozygosity within populations,which can exacerbate inbreeding depression by exposing homozygous deleterious alleles that are responsible for declines in fitness traits.In small populations,genetic purging that occurs under the pressure of natural selection acts as an opposing force,contributing to a reduction of deleterious alleles.Both inbreeding and genetic purging are paramount in the field of conservation genomics.The Amur tiger(Panthera tigris altaica)lives in small populations in the forests of Northeast Asia and is among the most endangered animals on the planet.Using genome-wide assessment and comparison,we reveal substantially higher and more extensive inbreeding in wild Amur tigers(F_(ROH)=0.50)than in captive individuals(F_(ROH)=0.24).However,a relatively reduced number of lossof-function mutations in wild Amur tigers is observed compared to captive individuals,indicating genetic purging of inbreeding load with relatively large-effect alleles.The higher ratio of homozygous mutation load and number of fixed damaging alleles in the wild population indicates a less-efficient genetic purging,with purifying selection also contributing to this process.These findings provide valuable insights for the future conservation of Amur tigers.展开更多
Use of wastewater for irrigation has become indispensable worldwide due to accelerating water scarcity, and it also carries a social dimension of poverty reduction in developing countries. However, the impacts of wast...Use of wastewater for irrigation has become indispensable worldwide due to accelerating water scarcity, and it also carries a social dimension of poverty reduction in developing countries. However, the impacts of wastewater irrigation on soil properties are still insufficiently understood, especially with regard to change in soil microbial community characteristics. The present study presents an assessment of soil bacterial communities subjecting to different irrigation waters. We conducted soil sampling in farmlands irrigated with wastewater, river water and groundwater respectively in an arid region of China and performed a metagenomic survey of microbial populations using the prokaryotic 16S ribosomal RAN gene. It sheds new light on possible alteration of soil bacterial diversity due to irrigation water. It also reveals that the relative abundance of nitrifying bacteria is greater in soil irrigated with river water than soil irrigated with wastewater. The opposite is true for denitrifying bacteria. The findings serve as a call for further in-depth study to explore the long-term responses of soil microbial communities to irrigation waters for the sake of environmentally sound watershed management.展开更多
Precision medicine has become a cornerstone in modern therapeutic strategies, with nucleic acid aptamers emerging aspivotal tools due to their unique properties. These oligonucleotide fragments, selected through the S...Precision medicine has become a cornerstone in modern therapeutic strategies, with nucleic acid aptamers emerging aspivotal tools due to their unique properties. These oligonucleotide fragments, selected through the Systematic Evolution ofLigands by Exponential Enrichment process, exhibit high affinity and specificity toward their targets, such as DNA, RNA,proteins, and other biomolecules. Nucleic acid aptamers offer significant advantages over traditional therapeutic agents,including superior biological stability, minimal immunogenicity, and the capacity for universal chemical modifications thatenhance their in vivo performance and targeting precision. In the realm of osseous tissue repair and regeneration, a complexphysiological process essential for maintaining skeletal integrity, aptamers have shown remarkable potential in influencingmolecular pathways crucial for bone regeneration, promoting osteogenic differentiation and supporting osteoblast survival. Byengineering aptamers to regulate inflammatory responses and facilitate the proliferation and differentiation of fibroblasts,these oligonucleotides can be integrated into advanced drug delivery systems, significantly improving bone repair efficacywhile minimizing adverse effects. Aptamer-mediated strategies, including the use of siRNA and miRNA mimics or inhibitors,have shown efficacy in enhancing bone mass and microstructure. These approaches hold transformative potential for treatinga range of orthopedic conditions like osteoporosis, osteosarcoma, and osteoarthritis. This review synthesizes the molecularmechanisms and biological roles of aptamers in orthopedic diseases, emphasizing their potential to drive innovative andeffective therapeutic interventions.展开更多
BACKGROUND Hepatic stellate cell(HSC)activation is key to liver fibrosis.Targeting DNA methylation shows promise.Zebularine,a methylation inhibitor,may suppress HSC activation via the calcineurin(CaN)/NFAT3 pathway.Ma...BACKGROUND Hepatic stellate cell(HSC)activation is key to liver fibrosis.Targeting DNA methylation shows promise.Zebularine,a methylation inhibitor,may suppress HSC activation via the calcineurin(CaN)/NFAT3 pathway.Magnetic resonance imaging(MRI)is a noninvasive tool for evaluating liver fibrosis evaluation tool,but multiparametric MRI for zebularine’s effects in liver fibrosis mouse models has not been studied.AIM To clarify the anti-fibrosis mechanism and MRI-evaluated efficacy of zebularine.METHODS In vitro,transforming growth factor(TGF)-β1-stimulated human HSCs(LX-2)were treated with zebularine.α-smooth muscle actin,fibrotic and anti-fibrotic gene levels,and regulator of calcineurin1(RCAN1)regulation were measured.In vivo,carbon tetrachloride(CCl_(4))-induced liver fibrosis in mice was treated with zebularine,and fibrosis was evaluated using various biochemical,histopathological,and MRI methods.RESULTS Zebularine upregulated RCAN1.4 protein(P<0.01)and inhibited the CaN/NFAT3 pathway(P<0.05).In HSCs,TGF-β1 reduced anti-fibrotic gene massage RNA(mRNA)and increased fibrotic mRNA(P<0.05),whereas zebularine had the opposite effects(P<0.01,P<0.05).CCl4-treated mice exhibited increases in various fibrosis-related indices,all of which were reversed by zebularine treatment(P<0.05).CONCLUSION Zebularine may reduce LX-2 activation and extracellular matrix deposition via RCAN1.4 and CaN/NFAT3 path-ways.Multiparametric MRI can assess its efficacy,suggesting zebularine’s potential as a liver fibrosis treatment.展开更多
This study begins by exploring the typical practical applications of phase‐change materials(PCMs)in various industries,highlighting their importance in energy storage,temperature regulation,and thermal management.It ...This study begins by exploring the typical practical applications of phase‐change materials(PCMs)in various industries,highlighting their importance in energy storage,temperature regulation,and thermal management.It then emphasizes the necessity of flame‐retardant functionalization tailored to the specific application scenarios of PCMs,especially considering their use in safety‐critical environments such as electronics,automotive,and construction.The classic characterization methods for assessing the flame‐retardant properties of PCM are introduced in detail,including the limiting oxygen index,the vertical burning test,and the cone calorimeter,which are widely recognized standards in material safety testing.Additionally,newly developed methods for evaluating combustion safety are discussed,such as direct combustion tests,candle combustion experiments,and back temperature response,which offer a more comprehensive understanding of the material's fire resistance.Following this,this study provides a thorough summary and categorization of the flame‐retardant strategies used in PCMs,divided into four main approaches:(1)incorporation of external flame retardants,(2)use of flame‐retardant microcapsules,(3)development of flame‐retardant support materials,and(4)creation of intrinsic flame‐retardant PCMs.Each strategy is critically analyzed in terms of effectiveness,applicability,and potential challenges.Lastly,the conclusion provides an overview of the current state of flame‐retardant PCMs,offering insights into future development directions,including the pursuit of more sustainable and efficient flame‐retardant solutions,as well as prospects for their broader adoption in various industries.展开更多
Background:The advent of the self-media age,digital humanities,and artificial intelligence(AI)technologies is gradually reshaping the narrative frameworks of the history of science and technology in general and the hi...Background:The advent of the self-media age,digital humanities,and artificial intelligence(AI)technologies is gradually reshaping the narrative frameworks of the history of science and technology in general and the history of medicine in particular,as it transforms the specific shape of contemporary medical science and health communication practice with the help of interactive,scenario-based communication ecosystems.Methods:This paper focuses on the interactive relationship between the history of science and science communication,employing historical tracing and case study comparison as research methods to explore the pathways and innovative models for reintegrating the history of science and technology including the history of medicine into contemporary scientific discourse.Results:The study finds that in the Chinese context,three key pathways facilitate the engagement of the history of science and technology including the history of medicine in science communication:administrative intervention,value reconstruction,and personalized adaptation.Specifically,administrative intervention promotes the integration of the history of science education into talent development through policy design;value reconstruction,centered on the scientific spirit,enhances societal cultural recognition of technological progress;and personalized adaptation leverages big data and social media technologies to enable precise and tailored knowledge dissemination.Conclusion:The rise of the“web-based knowledge brokering model”in the era of social media has introduced professional knowledge brokers,ensuring the accuracy and accessibility of science communication.These innovations not only serve as decision-making simulation tools for medical science and health communication,linking historical insights with contemporary practice,but also provide theoretical foundations and practical paradigms for realizing the value of the history of science and technology in the digital era.展开更多
BACKGROUND Patients with postoperative severe acute pancreatitis(SAP)in the intensive care unit(ICU)face complex challenges arising from physiological and microenvironmental imbalances,psychological stress,and the int...BACKGROUND Patients with postoperative severe acute pancreatitis(SAP)in the intensive care unit(ICU)face complex challenges arising from physiological and microenvironmental imbalances,psychological stress,and the interaction of multiple environmental factors.Traditional nursing models inadequately address this integrated microenvironment,highlighting the need for microenvironment theory-based nursing interventions to optimize outcomes.AIM To evaluate the impact of a microenvironment theory-based nursing intervention model on the prognosis of patients with postoperative SAP in the ICU.METHODS Between January 2022 and December 2024,106 patients with SAP who were admitted to ICU of the Fourth Affiliated Hospital of Soochow University(Suzhou Dushu Lake Hospital)were randomly assigned to two groups:(1)A control group(n=53,routine care);and(2)An observation group(n=53,routine care plus microenvironment theory-based nursing).Postoperative recovery,psychological distress,disease severity,and complication rates were compared between groups.RESULTS The observation group had significantly shorter postoperative flatus,defecation,and hospital stay compared with the control group(P<0.05).The Hamilton Depression Rating Scale(17-item)and Hamilton Anxiety Rating Scale(14-item)scores in the observation group were significantly lower than those in the control group(P<0.05).The observation group had a lower Acute Physiology and Chronic Health Evaluation II score(P<0.05)compared with the control group.The postoperative complication rates were 5.66%(3/53)and 18.87%(10/53)in the observation group and control group,respectively(P<0.05).CONCLUSION In patients with SAP,the microenvironment theory-based nursing intervention model facilitated postoperative recovery,alleviated depression and anxiety,reduced disease severity,and decreased postoperative complications.展开更多
CD8^(+)T cell-based immune-therapeutics,including immune checkpoint inhibitors and adoptive cell therapies(tumor-infiltrating lymphocytes(TILs),T cell receptor-engineered T cells(TCR-T),chimeric antigen receptor T cel...CD8^(+)T cell-based immune-therapeutics,including immune checkpoint inhibitors and adoptive cell therapies(tumor-infiltrating lymphocytes(TILs),T cell receptor-engineered T cells(TCR-T),chimeric antigen receptor T cells(CAR-T)),have achieved significant successes and prolonged patient survival to varying extents and even achieved cure in some cases.However,immunotherapy resistance and tumor insusceptibility frequently occur,leading to treatment failure.Recent evidences have highlighted the ponderance of tumor cells metabolic reprogramming in establishing an immunosuppressive milieu through the secretion of harmful metabolites,immune-inhibitory cytokines,and alteration of gene expression,which suppress the activity of immune cells,particularly CD8^(+)T cells to evade immune surveillance.Therefore,targeting tumor cell metabolic adaptations to reshape the immune microenvironment holds promise as an immunomodulatory strategy to facilitate immunotherapy.Here,we summarize recent advances in the crosstalk between immunotherapy and tumor reprogramming,focusing on the regulatory mechanisms underlying tumor cell glucose metabolism,amino acid metabolism,and lipid metabolism in influencing CD8^(+)T cells to provide promising metabolic targets or combinational strategies for immunotherapy.展开更多
The study of BiFeO_(3)-0.3BaTiO_(3) ceramics has gained significant attention due to their high Curie temperature(TC≥450℃)and excellent piezoelectric properties(d33≥200 pC·N^(−1)).These are particularly pronou...The study of BiFeO_(3)-0.3BaTiO_(3) ceramics has gained significant attention due to their high Curie temperature(TC≥450℃)and excellent piezoelectric properties(d33≥200 pC·N^(−1)).These are particularly pronounced near the morphotropic phase boundary(MPB)region where coexisting rhombohedral and pseudocubic(R-PC)phases are observed.In addition,as the BaTiO_(3) content increases,BiFeO_(3)-BaTiO_(3) ceramics gradually become dominated by a single pseudocubic(PC-)phase.This shift results in a decrease in piezoelectric properties but an enhancement in strain performance.However,the underlying mechanism remains unclear.The high strain properties observed in non-MPB compositions provide a motivation for further investigation into these mechanisms.This paper presents a detailed analysis of the electric-field and temperature-induced domain structure evolution in BiFeO_(3)-0.4BaTiO_(3),which is predominately characterized by the PC phase.Piezoresponse force microscope(PFM)observations reveal the presence of nanodomains and stripy domains associated with polar nanoregions(PNRs),as well as relaxor ferroelectrics(RFEs)and/or ferroelectrics(FEs).The RFEs exhibit a significantly better strain response than the FEs,providing direct evidence for the enhanced strain properties of RFEs.Elevated-temperature Raman spectroscopy confirms a decrease in B-O bonding and BO6 deformation,along with an increase in structural symmetry,indicating the formation of RFEs and/or PNRs.The phase diagram shows the Burns temperature(TB),dielectric maxima temperature(Tm)and freezing temperature(Tf)evaluated from the dielectric spectra;the temperature-induced evolution of domain structures;and the sequential quasi-dielectric states:PNRs,RFEs and FEs.The evolution of the domain structure,including the morphology and ratio of FEs,RFEs and PNRs,induced by either electric-fields or temperature strongly affects the strain properties of RFEs.A superior piezoelectric coefficient of d33*=533 pm·V^(−1) at 40 kV·cm^(−1) and a large electric strain of Suni=0.285%are obtained.These results further validate that domain modulation can effectively enhance the strain properties of BiFeO_(3)-BaTiO_(3) ceramics,which makes them promising candidates for actuator applications.展开更多
To address the limitations of conventional energy systems and optimize the energy conversion pathways and efficiency,a type of“five-in-one”multifunctional phase-change composite with magnetothermal,electrothermal,so...To address the limitations of conventional energy systems and optimize the energy conversion pathways and efficiency,a type of“five-in-one”multifunctional phase-change composite with magnetothermal,electrothermal,solar-thermal,and thermoelectric energy conversion and electromagnetic shielding functions is developed for multipurpose applications.Such a novel phase-change composite is fabricated by an innovative combination of paraffin wax(PW)as a phase-change material and a carbonized polyimide/Kevlar/graphene oxide@ZIF-67 complex aerogel as a supporting material.The carbonized complex aerogel exhibits a unique bidirectional porous structure with high porosity and robust skeleton to support the loading of PW.The reduced graphene oxide and Co NC resulting from high-temperature carbonization are anchored on the aerogel skeleton to generate high thermal conduction and magnetic effect,enhancing the phonon and electron transfer of the aerogel and improving its energy conversion efficiency.The phase-change composite not only exhibits excellent solar-thermal,thermoelectric,electrothermal,and magnetothermal energy conversion performance,but also achieves high electromagnetic interference shielding effectiveness of 66.2 d B in the X-band.The introduction of PW significantly improves the thermal energy-storage capacity during multi-energy conversion.The developed composite exhibits great application potential for efficient solar energy utilization,sustainable power generation,outdoor deicing,human thermal therapy,and electronic device protection.展开更多
Large models,exemplified by ChatGPT,have reached the pinnacle of contemporary artificial intelligence(AI).However,they are plagued by three inherent drawbacks:excessive training data and computing power consumption,su...Large models,exemplified by ChatGPT,have reached the pinnacle of contemporary artificial intelligence(AI).However,they are plagued by three inherent drawbacks:excessive training data and computing power consumption,susceptibility to catastrophic forgetting,and a deficiency in logical reasoning capabilities within black-box models.To address these challenges,we draw insights from human memory mechanisms to introduce“machine memory,”which we define as a storage structure formed by encoding external information into a machine-representable and computable format.Centered on machine memory,we propose the brand-new machine memory intelligence(M^(2)I)framework,which encompasses representation,learning,and reasoning modules and loops.We explore the key issues and recent advances in the four core aspects of M^(2)I,including neural mechanisms,associative representation,continual learning,and collaborative reasoning within machine memory.M^(2)I aims to liberate machine intelligence from the confines of data-centric neural networks and fundamentally break through the limitations of existing large models,driving a qualitative leap from weak to strong AI.展开更多
Zinc-based batteries(ZBBs)have garnered significant attention in the field of energy storage and conversion owing to their exceptional advantages,including high energy density,intrinsic environmental benignity,low mat...Zinc-based batteries(ZBBs)have garnered significant attention in the field of energy storage and conversion owing to their exceptional advantages,including high energy density,intrinsic environmental benignity,low material cost,as well as enhanced safety characteristics.Nevertheless,several critical challenges persist,predominantly the propensity for dendrite growth,inherent kinetic limitations,deleterious electrode side reactions,and perplexing shuttle effects,which collectively impede the practical implementation and commercial viability of ZBBs.In this context,fibers fabricated via electrospinning technology exhibit remarkable advantages in terms of enhanced specific surface area,improved electrical conductivity,and superior mechanical integrity,while also affording optimized pore structures.These unique features render electrospinning fibers particularly promising for addressing the key issues that limit ZBBs performance,including energy density,charge/discharge rate capabilities,and cycling stability.So,it is very necessary to summarize electrospinning technology application in ZBBs.This paper firstly analyzes the fundamental mechanisms and inherent challenges of ZBBs including zincion,zinc-air,and zinc-halide batteries.Subsequently,the application of electrospinning fiber structures in anodes,cathodes,separators,and electrolytes optimization for ZBBs is summarized.Finally,the prospect of electrospinning technology in ZBBs is envisioned,and existing challenges are presented for its further application.展开更多
CdSe nanoplatelets(NPLs)are promising candidates for on-chip light sources,yet their performance is hindered by surface defects and inefficient optical gain.Herein,we demonstrate that CdSeS crown passivation significa...CdSe nanoplatelets(NPLs)are promising candidates for on-chip light sources,yet their performance is hindered by surface defects and inefficient optical gain.Herein,we demonstrate that CdSeS crown passivation significantly enhances the photophysical property of CdSe NPLs.Laser spectroscopy techniques reveal suppressed electronic and hole trapping at lateral surfaces,leading to a 4.2-fold increase in photoluminescence quantum yield and a shortened emission lifetime from13.5 to 4.8 ns.In addition,amplified spontaneous emission is achieved under nanosecond pulse pumping,with thresholds of0.75 to 0.16 mJ/cm^(2)for CdSe and CdSe/CdSeS NPLs,respectively.By integrating CdSe/CdSeS NPLs with high-refractiveindex SiO2scatters,coherent random lasing is realized at a threshold of 0.21 mJ/cm^(2).These findings highlight the critical role of lateral surface passivation in optimizing optical gain and pave the way for low-cost,multifunctional nanophotonic devices.展开更多
Precise regulation of atomic and electronic structures of two-dimensional tungsten disulfide(WS_(2))is significant for rational design of high-performance and low-cost catalyst for acetylene hydrogenation to ethylene(...Precise regulation of atomic and electronic structures of two-dimensional tungsten disulfide(WS_(2))is significant for rational design of high-performance and low-cost catalyst for acetylene hydrogenation to ethylene(AHE),yet remains a major challenge.Herein,we report that by substituting a W atom of WS_(2) with a series of transition metal atoms,sulfur vacancy-confined Cu in the WS_(2) basal plane(Cu@WS_(2)-Sv)is theoretically screened as a superior non-noble metal-based catalyst with higher activity,selectivity,and stability for the AHE than other candidates.The co-adsorption of C_(2)H_(2) and H_(2) and hydrogenation of C_(2)H_(3)^(*) to C_(2)H_(4)^(*) are revealed as the key steps establishing a volcano-like activity trend among the candidates,which present Cu@WS_(2)-Sv as the optimum catalyst combined with molecular dynamics and reaction kinetics analyses.The kinetically more favorable desorption of C_(2)H_(4) than the over hydrogenation path validates a higher selectivity toward C_(2)H_(4) over C_(2)H_(6).Furthermore,a machine-learning model reveals the significant effect of d-electron number and electronegativity of the metal heteroatoms in modulating the AHE activity.展开更多
基金supported by the National Key Research and Development Program(Grant No.2024YFA0917200)the Projects of the Chinese Center for Disease Control and Prevention(Grant No.BB2110240093)World Medical History under the Education Innovation Plan of the University of Science and Technology of China(Grant No.2024YCHX07).
文摘Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide technology for good and prevent and control technological risks has become an important issue of global concern.Research on science and technology ethics is dedicated to integrating ethical theories into governance practices and constructing ethical models that adapt to the development of the times.Methods:This article systematically reviews the six core approaches of scientific and technological ethics thought,including technological autonomy and political philosophy criticism,responsibility ethics and intergenerational obligations,technological intermediation and the integration of life and the world,ethical principles and normative frameworks,participatory governance and ethical practice innovation,as well as domain-specific ethical norms,thereby constructing an ethical analysis framework applicable to medical technology risks.And cross-analysis was conducted by taking medical events such as gene editing and xenotransplantation as examples.Results:Research shows that a single ethical approach has limitations in addressing complex medical ethical challenges,while the six approaches are complementary and synergistic.By criticizing technological autonomy,establishing a responsibility ethics orientation,setting the bottom line of ethical principles,promoting participatory governance,formulating domain norms,and continuously reflecting on the intermediary nature of technology,a multi-level and dynamically adaptive governance system for scientific and technological ethics can be constructed.Conclusion:The key to addressing contemporary medical ethics challenges lies in the comprehensive application of science and technology ethics theories and the integration of ethical considerations throughout the entire process of scientific and technological research and development.In the future,a governance framework that adapts to the development of new technologies should be established to promote cross-cultural and cross-disciplinary ethical dialogue and public participation,ensuring that scientific and technological innovation always serves the dignity of human life and overall well-being.
基金supported by the National Natural Science Foundation of China(grant numbers:82071077,81771057,and 81400477 to H.L.82181340279,82071110,and 81771066 to Z.C.)+1 种基金“the Fundamental Research Funds for the Central Universities”(no.2042021kf0197)“The Young Top-notch Talent Cultivation Program of Hubei Province”to H.L.
文摘Genome-wide association studies(GWASs) are the most widely used method to identify genetic risk loci associated with orofacial clefts(OFC). However, despite the increasing size of cohort, GWASs are still insufficient to detect all the heritability,suggesting there are more associations under the current stringent statistical threshold. In this study, we obtained an integrated epigenomic dataset based on the chromatin conformation of a human oral epithelial cell line(HIOEC) using RNA-seq, ATAC-seq,H3K27ac Ch IP-seq, and DLO Hi-C. Presumably, this epigenomic dataset could reveal the missing functional variants located in the oral epithelial cell active enhancers/promoters along with their risk target genes, despite relatively less-stringent statistical association with OFC. Taken a non-syndromic cleft palate only(NSCPO) GWAS data of the Chinese Han population as an example, 3664 SNPs that cannot reach the strict significance threshold were subjected to this functional identification pipeline.In total, 254 potential risk SNPs residing in active cis-regulatory elements interacting with 1 718 promoters of oral epitheliumexpressed genes were screened. Gapped k-mer machine learning based on enhancers interacting with epithelium-expressed genes along with in vivo and in vitro reporter assays were employed as functional validation. Among all the potential SNPs, we chose and confirmed that the risk alleles of rs560789 and rs174570 reduced the epithelial-specific enhancer activity by preventing the binding of transcription factors related to epithelial development. In summary, we established chromatin conformation datasets of human oral epithelial cells and provided a framework for testing and understanding how regulatory variants impart risk for clefts.
基金financially supported by the National Natural Science Foundation of China(No.51904026)the Fundamental Research Funds for the Central Universities(No.06500108)。
文摘Hydrogen displays the potential to partially replace pulverized coal injection(PCI)in the blast furnace,and it can reduce CO_(2)emissions.In this paper,a three-dimensional mathematical model of hydrogen and pulverized coal co-injection in blast furnace tuyere was established through numerical simulation,and the effect of hydrogen injection and oxygen enrichment interaction on pulverized coal combustion and raceway smelting was investigated.The simulation results indicate that when the coal injection rate decreased from 36 to 30t/h and the hydrogen injection increased from 0 to 3600 m^(3)/h,the CO_(2)emissions decreased from 1860 to 1551 kg/t,which represents a16.6%reduction,and the pulverized coal burnout decreased from 70.1%to 63.7%.The heat released from hydrogen combustion can not only promote the volatilization of pulverized coal but also affect the combustion reaction between volatilization and oxygen,which resulted in a decrease in the temperature at the end of the raceway.Co-injection of hydrogen with PCI increased the wall temperature near the upper half part of the raceway and at the outlet of the tuyere,which required a high cooling efficiency to extend the service life of the blast furnace.The increase in oxygen level compensated for the decreased average temperature in the raceway due to hydrogen injection.The increase in the oxygen content by 3%while maintaining constant hydrogen and PCI injection rates increased the burnout and average raceway temperature by 4.2%and 43 K,respectively.The mole fraction of CO and H_(2) production increased by 0.04 and 0.02,respectively.Burnout can be improved through optimization of the particle size distribution of pulverized coal.
基金supported by the Fundamental Research Funds for the Central Universities of China(2572022DQ03)the National Natural Science Foundation of China(32170517)+2 种基金the Guangdong Provincial Key Laboratory of Genome Read and Write(2017B030301011)the Start-up Scientific Foundation of Northeast Forestry University(60201524043)supported by China National GeneBank(CNGB).
文摘Inbreeding increases genome homozygosity within populations,which can exacerbate inbreeding depression by exposing homozygous deleterious alleles that are responsible for declines in fitness traits.In small populations,genetic purging that occurs under the pressure of natural selection acts as an opposing force,contributing to a reduction of deleterious alleles.Both inbreeding and genetic purging are paramount in the field of conservation genomics.The Amur tiger(Panthera tigris altaica)lives in small populations in the forests of Northeast Asia and is among the most endangered animals on the planet.Using genome-wide assessment and comparison,we reveal substantially higher and more extensive inbreeding in wild Amur tigers(F_(ROH)=0.50)than in captive individuals(F_(ROH)=0.24).However,a relatively reduced number of lossof-function mutations in wild Amur tigers is observed compared to captive individuals,indicating genetic purging of inbreeding load with relatively large-effect alleles.The higher ratio of homozygous mutation load and number of fixed damaging alleles in the wild population indicates a less-efficient genetic purging,with purifying selection also contributing to this process.These findings provide valuable insights for the future conservation of Amur tigers.
文摘Use of wastewater for irrigation has become indispensable worldwide due to accelerating water scarcity, and it also carries a social dimension of poverty reduction in developing countries. However, the impacts of wastewater irrigation on soil properties are still insufficiently understood, especially with regard to change in soil microbial community characteristics. The present study presents an assessment of soil bacterial communities subjecting to different irrigation waters. We conducted soil sampling in farmlands irrigated with wastewater, river water and groundwater respectively in an arid region of China and performed a metagenomic survey of microbial populations using the prokaryotic 16S ribosomal RAN gene. It sheds new light on possible alteration of soil bacterial diversity due to irrigation water. It also reveals that the relative abundance of nitrifying bacteria is greater in soil irrigated with river water than soil irrigated with wastewater. The opposite is true for denitrifying bacteria. The findings serve as a call for further in-depth study to explore the long-term responses of soil microbial communities to irrigation waters for the sake of environmentally sound watershed management.
基金Key research and development projects of Sichuan Science and Technology Plan Project(2024YFFK0135)Fujian Provincial Natural Science Foundation of China(2024J011450).
文摘Precision medicine has become a cornerstone in modern therapeutic strategies, with nucleic acid aptamers emerging aspivotal tools due to their unique properties. These oligonucleotide fragments, selected through the Systematic Evolution ofLigands by Exponential Enrichment process, exhibit high affinity and specificity toward their targets, such as DNA, RNA,proteins, and other biomolecules. Nucleic acid aptamers offer significant advantages over traditional therapeutic agents,including superior biological stability, minimal immunogenicity, and the capacity for universal chemical modifications thatenhance their in vivo performance and targeting precision. In the realm of osseous tissue repair and regeneration, a complexphysiological process essential for maintaining skeletal integrity, aptamers have shown remarkable potential in influencingmolecular pathways crucial for bone regeneration, promoting osteogenic differentiation and supporting osteoblast survival. Byengineering aptamers to regulate inflammatory responses and facilitate the proliferation and differentiation of fibroblasts,these oligonucleotides can be integrated into advanced drug delivery systems, significantly improving bone repair efficacywhile minimizing adverse effects. Aptamer-mediated strategies, including the use of siRNA and miRNA mimics or inhibitors,have shown efficacy in enhancing bone mass and microstructure. These approaches hold transformative potential for treatinga range of orthopedic conditions like osteoporosis, osteosarcoma, and osteoarthritis. This review synthesizes the molecularmechanisms and biological roles of aptamers in orthopedic diseases, emphasizing their potential to drive innovative andeffective therapeutic interventions.
基金Supported by the Health Research Foundation of Hunan Provincial Health Commission,No.W20243192Natural Science Foundation of Changsha,No.kq2403086+1 种基金National Natural Science Foundation of China,No.81571784Hunan Provincial Health Commission Hunan Provincial High-level Health Talent Major Scientific Research Project,No.R2023022.
文摘BACKGROUND Hepatic stellate cell(HSC)activation is key to liver fibrosis.Targeting DNA methylation shows promise.Zebularine,a methylation inhibitor,may suppress HSC activation via the calcineurin(CaN)/NFAT3 pathway.Magnetic resonance imaging(MRI)is a noninvasive tool for evaluating liver fibrosis evaluation tool,but multiparametric MRI for zebularine’s effects in liver fibrosis mouse models has not been studied.AIM To clarify the anti-fibrosis mechanism and MRI-evaluated efficacy of zebularine.METHODS In vitro,transforming growth factor(TGF)-β1-stimulated human HSCs(LX-2)were treated with zebularine.α-smooth muscle actin,fibrotic and anti-fibrotic gene levels,and regulator of calcineurin1(RCAN1)regulation were measured.In vivo,carbon tetrachloride(CCl_(4))-induced liver fibrosis in mice was treated with zebularine,and fibrosis was evaluated using various biochemical,histopathological,and MRI methods.RESULTS Zebularine upregulated RCAN1.4 protein(P<0.01)and inhibited the CaN/NFAT3 pathway(P<0.05).In HSCs,TGF-β1 reduced anti-fibrotic gene massage RNA(mRNA)and increased fibrotic mRNA(P<0.05),whereas zebularine had the opposite effects(P<0.01,P<0.05).CCl4-treated mice exhibited increases in various fibrosis-related indices,all of which were reversed by zebularine treatment(P<0.05).CONCLUSION Zebularine may reduce LX-2 activation and extracellular matrix deposition via RCAN1.4 and CaN/NFAT3 path-ways.Multiparametric MRI can assess its efficacy,suggesting zebularine’s potential as a liver fibrosis treatment.
基金supported by NEWSAFE(No.:PID2022‐143324NA‐I00)Projects funded by MICIU(Ministerio de Ciencia,Innovación y Universidades)/AEI(Agencia Estatal de Investigación)/10.13039/501100011033 and,as appropriate,by“ERDF/EU”Ramón y Cajal Fellowship(No.:RYC2023‐045023‐I)funded by MICIU,and,as appropriate,“ESF Investing in your future.”This study was also partially supported by INC‐UDIT‐2025‐PRO21 and INC‐UDIT‐2025‐JCR24.
文摘This study begins by exploring the typical practical applications of phase‐change materials(PCMs)in various industries,highlighting their importance in energy storage,temperature regulation,and thermal management.It then emphasizes the necessity of flame‐retardant functionalization tailored to the specific application scenarios of PCMs,especially considering their use in safety‐critical environments such as electronics,automotive,and construction.The classic characterization methods for assessing the flame‐retardant properties of PCM are introduced in detail,including the limiting oxygen index,the vertical burning test,and the cone calorimeter,which are widely recognized standards in material safety testing.Additionally,newly developed methods for evaluating combustion safety are discussed,such as direct combustion tests,candle combustion experiments,and back temperature response,which offer a more comprehensive understanding of the material's fire resistance.Following this,this study provides a thorough summary and categorization of the flame‐retardant strategies used in PCMs,divided into four main approaches:(1)incorporation of external flame retardants,(2)use of flame‐retardant microcapsules,(3)development of flame‐retardant support materials,and(4)creation of intrinsic flame‐retardant PCMs.Each strategy is critically analyzed in terms of effectiveness,applicability,and potential challenges.Lastly,the conclusion provides an overview of the current state of flame‐retardant PCMs,offering insights into future development directions,including the pursuit of more sustainable and efficient flame‐retardant solutions,as well as prospects for their broader adoption in various industries.
基金The National Key R&D project granted by the Ministry of Science and Technology(2024YFA0917200)Digital Museum Construction Project of Chinese Centre for Disease Control and Prevention(BB2110240080)Science Communication Project of Chinese Academy of Sciences(CX2090000008).
文摘Background:The advent of the self-media age,digital humanities,and artificial intelligence(AI)technologies is gradually reshaping the narrative frameworks of the history of science and technology in general and the history of medicine in particular,as it transforms the specific shape of contemporary medical science and health communication practice with the help of interactive,scenario-based communication ecosystems.Methods:This paper focuses on the interactive relationship between the history of science and science communication,employing historical tracing and case study comparison as research methods to explore the pathways and innovative models for reintegrating the history of science and technology including the history of medicine into contemporary scientific discourse.Results:The study finds that in the Chinese context,three key pathways facilitate the engagement of the history of science and technology including the history of medicine in science communication:administrative intervention,value reconstruction,and personalized adaptation.Specifically,administrative intervention promotes the integration of the history of science education into talent development through policy design;value reconstruction,centered on the scientific spirit,enhances societal cultural recognition of technological progress;and personalized adaptation leverages big data and social media technologies to enable precise and tailored knowledge dissemination.Conclusion:The rise of the“web-based knowledge brokering model”in the era of social media has introduced professional knowledge brokers,ensuring the accuracy and accessibility of science communication.These innovations not only serve as decision-making simulation tools for medical science and health communication,linking historical insights with contemporary practice,but also provide theoretical foundations and practical paradigms for realizing the value of the history of science and technology in the digital era.
文摘BACKGROUND Patients with postoperative severe acute pancreatitis(SAP)in the intensive care unit(ICU)face complex challenges arising from physiological and microenvironmental imbalances,psychological stress,and the interaction of multiple environmental factors.Traditional nursing models inadequately address this integrated microenvironment,highlighting the need for microenvironment theory-based nursing interventions to optimize outcomes.AIM To evaluate the impact of a microenvironment theory-based nursing intervention model on the prognosis of patients with postoperative SAP in the ICU.METHODS Between January 2022 and December 2024,106 patients with SAP who were admitted to ICU of the Fourth Affiliated Hospital of Soochow University(Suzhou Dushu Lake Hospital)were randomly assigned to two groups:(1)A control group(n=53,routine care);and(2)An observation group(n=53,routine care plus microenvironment theory-based nursing).Postoperative recovery,psychological distress,disease severity,and complication rates were compared between groups.RESULTS The observation group had significantly shorter postoperative flatus,defecation,and hospital stay compared with the control group(P<0.05).The Hamilton Depression Rating Scale(17-item)and Hamilton Anxiety Rating Scale(14-item)scores in the observation group were significantly lower than those in the control group(P<0.05).The observation group had a lower Acute Physiology and Chronic Health Evaluation II score(P<0.05)compared with the control group.The postoperative complication rates were 5.66%(3/53)and 18.87%(10/53)in the observation group and control group,respectively(P<0.05).CONCLUSION In patients with SAP,the microenvironment theory-based nursing intervention model facilitated postoperative recovery,alleviated depression and anxiety,reduced disease severity,and decreased postoperative complications.
基金funded by National Natural Science Foundation of China(Grant Nos.:82373336,and 82303238,Sichuan Science and Technology Department,China(Grant Nos.:2024NSFSC1945,and 2023NSFSC0667)The Third People's Hospital of Chengdu Clinical Research Program,China(Program Nos.:CSY-YN-01-2023-013,CSY-YN-01-2023-005,and CSY-YN-03-2024-003)+1 种基金Sichuan University“From 0 to 1”Innovative Research Project,China(Project No.:2023SCUH0024)Health Commission of Chengdu,China(Grant No.:2024291).
文摘CD8^(+)T cell-based immune-therapeutics,including immune checkpoint inhibitors and adoptive cell therapies(tumor-infiltrating lymphocytes(TILs),T cell receptor-engineered T cells(TCR-T),chimeric antigen receptor T cells(CAR-T)),have achieved significant successes and prolonged patient survival to varying extents and even achieved cure in some cases.However,immunotherapy resistance and tumor insusceptibility frequently occur,leading to treatment failure.Recent evidences have highlighted the ponderance of tumor cells metabolic reprogramming in establishing an immunosuppressive milieu through the secretion of harmful metabolites,immune-inhibitory cytokines,and alteration of gene expression,which suppress the activity of immune cells,particularly CD8^(+)T cells to evade immune surveillance.Therefore,targeting tumor cell metabolic adaptations to reshape the immune microenvironment holds promise as an immunomodulatory strategy to facilitate immunotherapy.Here,we summarize recent advances in the crosstalk between immunotherapy and tumor reprogramming,focusing on the regulatory mechanisms underlying tumor cell glucose metabolism,amino acid metabolism,and lipid metabolism in influencing CD8^(+)T cells to provide promising metabolic targets or combinational strategies for immunotherapy.
基金supported by the National Key Research and Development Program(No.2022YFB3807400)the National Natural Science Foundation of China(Nos.52072028 and 52032007).
文摘The study of BiFeO_(3)-0.3BaTiO_(3) ceramics has gained significant attention due to their high Curie temperature(TC≥450℃)and excellent piezoelectric properties(d33≥200 pC·N^(−1)).These are particularly pronounced near the morphotropic phase boundary(MPB)region where coexisting rhombohedral and pseudocubic(R-PC)phases are observed.In addition,as the BaTiO_(3) content increases,BiFeO_(3)-BaTiO_(3) ceramics gradually become dominated by a single pseudocubic(PC-)phase.This shift results in a decrease in piezoelectric properties but an enhancement in strain performance.However,the underlying mechanism remains unclear.The high strain properties observed in non-MPB compositions provide a motivation for further investigation into these mechanisms.This paper presents a detailed analysis of the electric-field and temperature-induced domain structure evolution in BiFeO_(3)-0.4BaTiO_(3),which is predominately characterized by the PC phase.Piezoresponse force microscope(PFM)observations reveal the presence of nanodomains and stripy domains associated with polar nanoregions(PNRs),as well as relaxor ferroelectrics(RFEs)and/or ferroelectrics(FEs).The RFEs exhibit a significantly better strain response than the FEs,providing direct evidence for the enhanced strain properties of RFEs.Elevated-temperature Raman spectroscopy confirms a decrease in B-O bonding and BO6 deformation,along with an increase in structural symmetry,indicating the formation of RFEs and/or PNRs.The phase diagram shows the Burns temperature(TB),dielectric maxima temperature(Tm)and freezing temperature(Tf)evaluated from the dielectric spectra;the temperature-induced evolution of domain structures;and the sequential quasi-dielectric states:PNRs,RFEs and FEs.The evolution of the domain structure,including the morphology and ratio of FEs,RFEs and PNRs,induced by either electric-fields or temperature strongly affects the strain properties of RFEs.A superior piezoelectric coefficient of d33*=533 pm·V^(−1) at 40 kV·cm^(−1) and a large electric strain of Suni=0.285%are obtained.These results further validate that domain modulation can effectively enhance the strain properties of BiFeO_(3)-BaTiO_(3) ceramics,which makes them promising candidates for actuator applications.
基金supported by the Beijing Natural Science Foundation(Grant No.:2242049)。
文摘To address the limitations of conventional energy systems and optimize the energy conversion pathways and efficiency,a type of“five-in-one”multifunctional phase-change composite with magnetothermal,electrothermal,solar-thermal,and thermoelectric energy conversion and electromagnetic shielding functions is developed for multipurpose applications.Such a novel phase-change composite is fabricated by an innovative combination of paraffin wax(PW)as a phase-change material and a carbonized polyimide/Kevlar/graphene oxide@ZIF-67 complex aerogel as a supporting material.The carbonized complex aerogel exhibits a unique bidirectional porous structure with high porosity and robust skeleton to support the loading of PW.The reduced graphene oxide and Co NC resulting from high-temperature carbonization are anchored on the aerogel skeleton to generate high thermal conduction and magnetic effect,enhancing the phonon and electron transfer of the aerogel and improving its energy conversion efficiency.The phase-change composite not only exhibits excellent solar-thermal,thermoelectric,electrothermal,and magnetothermal energy conversion performance,but also achieves high electromagnetic interference shielding effectiveness of 66.2 d B in the X-band.The introduction of PW significantly improves the thermal energy-storage capacity during multi-energy conversion.The developed composite exhibits great application potential for efficient solar energy utilization,sustainable power generation,outdoor deicing,human thermal therapy,and electronic device protection.
基金supported by the National Natural Science Foun-dation of China(62137002,62250009,62202367,82025020,and 82230072).
文摘Large models,exemplified by ChatGPT,have reached the pinnacle of contemporary artificial intelligence(AI).However,they are plagued by three inherent drawbacks:excessive training data and computing power consumption,susceptibility to catastrophic forgetting,and a deficiency in logical reasoning capabilities within black-box models.To address these challenges,we draw insights from human memory mechanisms to introduce“machine memory,”which we define as a storage structure formed by encoding external information into a machine-representable and computable format.Centered on machine memory,we propose the brand-new machine memory intelligence(M^(2)I)framework,which encompasses representation,learning,and reasoning modules and loops.We explore the key issues and recent advances in the four core aspects of M^(2)I,including neural mechanisms,associative representation,continual learning,and collaborative reasoning within machine memory.M^(2)I aims to liberate machine intelligence from the confines of data-centric neural networks and fundamentally break through the limitations of existing large models,driving a qualitative leap from weak to strong AI.
基金financially supported by the Key Research and Development Project of Hunan Province in China(No.2023GK2028)the Major Basic Research Projects in Hunan Province(No.2024JC0005)the National Natural Science Foundation of China Regional Joint Fund Key Program(No.U24A20302)
文摘Zinc-based batteries(ZBBs)have garnered significant attention in the field of energy storage and conversion owing to their exceptional advantages,including high energy density,intrinsic environmental benignity,low material cost,as well as enhanced safety characteristics.Nevertheless,several critical challenges persist,predominantly the propensity for dendrite growth,inherent kinetic limitations,deleterious electrode side reactions,and perplexing shuttle effects,which collectively impede the practical implementation and commercial viability of ZBBs.In this context,fibers fabricated via electrospinning technology exhibit remarkable advantages in terms of enhanced specific surface area,improved electrical conductivity,and superior mechanical integrity,while also affording optimized pore structures.These unique features render electrospinning fibers particularly promising for addressing the key issues that limit ZBBs performance,including energy density,charge/discharge rate capabilities,and cycling stability.So,it is very necessary to summarize electrospinning technology application in ZBBs.This paper firstly analyzes the fundamental mechanisms and inherent challenges of ZBBs including zincion,zinc-air,and zinc-halide batteries.Subsequently,the application of electrospinning fiber structures in anodes,cathodes,separators,and electrolytes optimization for ZBBs is summarized.Finally,the prospect of electrospinning technology in ZBBs is envisioned,and existing challenges are presented for its further application.
基金supported by the National Natural Science Foundation of China(Grant No.62174079)Guangdong Provincial Quantum Science Strategic Initiative(Grant No.GDZX2404006)Science,Technology and Innovation Commission of Shenzhen Municipality(Grant No.JCYJ20220530113015035)。
文摘CdSe nanoplatelets(NPLs)are promising candidates for on-chip light sources,yet their performance is hindered by surface defects and inefficient optical gain.Herein,we demonstrate that CdSeS crown passivation significantly enhances the photophysical property of CdSe NPLs.Laser spectroscopy techniques reveal suppressed electronic and hole trapping at lateral surfaces,leading to a 4.2-fold increase in photoluminescence quantum yield and a shortened emission lifetime from13.5 to 4.8 ns.In addition,amplified spontaneous emission is achieved under nanosecond pulse pumping,with thresholds of0.75 to 0.16 mJ/cm^(2)for CdSe and CdSe/CdSeS NPLs,respectively.By integrating CdSe/CdSeS NPLs with high-refractiveindex SiO2scatters,coherent random lasing is realized at a threshold of 0.21 mJ/cm^(2).These findings highlight the critical role of lateral surface passivation in optimizing optical gain and pave the way for low-cost,multifunctional nanophotonic devices.
文摘Precise regulation of atomic and electronic structures of two-dimensional tungsten disulfide(WS_(2))is significant for rational design of high-performance and low-cost catalyst for acetylene hydrogenation to ethylene(AHE),yet remains a major challenge.Herein,we report that by substituting a W atom of WS_(2) with a series of transition metal atoms,sulfur vacancy-confined Cu in the WS_(2) basal plane(Cu@WS_(2)-Sv)is theoretically screened as a superior non-noble metal-based catalyst with higher activity,selectivity,and stability for the AHE than other candidates.The co-adsorption of C_(2)H_(2) and H_(2) and hydrogenation of C_(2)H_(3)^(*) to C_(2)H_(4)^(*) are revealed as the key steps establishing a volcano-like activity trend among the candidates,which present Cu@WS_(2)-Sv as the optimum catalyst combined with molecular dynamics and reaction kinetics analyses.The kinetically more favorable desorption of C_(2)H_(4) than the over hydrogenation path validates a higher selectivity toward C_(2)H_(4) over C_(2)H_(6).Furthermore,a machine-learning model reveals the significant effect of d-electron number and electronegativity of the metal heteroatoms in modulating the AHE activity.
