Photocatalysis shows great promise in the field of solar energy conversion.One of the reasons for this is because it promotes the development of multi-field-coupled catalysis.In order to explore the principles of mult...Photocatalysis shows great promise in the field of solar energy conversion.One of the reasons for this is because it promotes the development of multi-field-coupled catalysis.In order to explore the principles of multi-field-coupled catalytic reactions,an in situ multi-field-coupled characterization technique is required.In this study,we obtained hydrogenated ST-01 TiO2 and observed enhanced catalytic activity by thermal coupled photocatalysis.In situ photoconductivity was employed to understand the activity enhancement.The effects of the reaction temperature,reaction atmosphere,and oxygen vacancy(Ov)on the photoconductivity of TiO2 were studied.After coupling thermal into photoconductivity measurement,highly active Ov-TiO2 displayed rapid decay of photoconductivity in a CO2 atmosphere and slow decay of photoconductivity in a N2 atmosphere.These phenomena revealed that photothermal coupling assisted the detrapping of electrons at the Ov surface and promoted electron transfer to CO2,which clearly explained the high photothermal catalytic activity of Ov-TiO2.This study demonstrated that photoconductivity is a useful tool to help understand photothermal catalytic phenomena.展开更多
Semiconductor oxides are widely used to achieve photocatalytic removal of NOx(NO and NO2) species. These materials also exhibit enhanced oxidation ability in thermally assisted photocatalysis;however, many of them ten...Semiconductor oxides are widely used to achieve photocatalytic removal of NOx(NO and NO2) species. These materials also exhibit enhanced oxidation ability in thermally assisted photocatalysis;however, many of them tend to be deactivated at high relative humidity(RH) levels. In the case of the benchmark P25 TiO2 photocatalyst, we observe a significant decrease in non-NO2 selectivity from 95.02% to 58.33% when RH increases from 20% to 80%. Interestingly, the porous TiO2(B) microspheres synthesized in this work exhibit 99% selectivity at 20% RH;the selectivity remains as high as 96.18% at 80% RH. The high humidity tolerance of the TiO2(B) sample can be ascribed to its strong water desorption capacity and easy O2 adsorption at elevated temperatures, which reflects the fact that the superoxide radical is the main active species for the deep oxidation of NOx. This work may inspire the design of efficient photothermal catalysts with application in NOx removal in hot and humid environments.展开更多
Perovskite solar cells(PSCs)have been developed over the past decade as the forefront of the state-of-theart photovoltaic technologies owing to their high efficiency and low cost,where nanostructured functional materi...Perovskite solar cells(PSCs)have been developed over the past decade as the forefront of the state-of-theart photovoltaic technologies owing to their high efficiency and low cost,where nanostructured functional materials play key roles in performance optimization.As a versatile class of two-dimensional(2D)materials,transition metal carbides/nitrides MXenes have gained enormous attentions in PSCs since 2018 due to their superior properties such as excellent metallic conductivity,abundant surface functional groups,tunable work functions,high optical transparency,and mechanical robustness.The explorations of MXenes are of significance in performance promotion and commercialization expansion of devices.As such,this review focuses on the diversified advantages of MXenes,comprehensively summarizing their applications and developments in PSCs as additives,electron/hole transporting layers,interfacial engineering layers,and electrodes in sequence and explaining the relevant mechanisms behind.Simultaneously,the problems emerged from the related studies are considered and the corresponding suggestions like opening up the type of MXenes usage,taking further insight of the modulation of surface termination groups on Fermi levels,understanding the effect on energy level structures of perovskite or other functional layers,and realizing commercialization,etc.are provided for the future in-depth explorations.This review is intended to provide overall perspective of the current status of MXenes and highlight the direction for the future advancements in MXenes design and processes towards efficient,stable,large-area,and low-cost PSCs.展开更多
Kesterite Cu2ZnSn(S,Se)4(CZTSSe)solar cells have drawn worldwide attention for their promising photovoltaics performance and earth-abundant element composition,yet the record efficiency of this type of device is still...Kesterite Cu2ZnSn(S,Se)4(CZTSSe)solar cells have drawn worldwide attention for their promising photovoltaics performance and earth-abundant element composition,yet the record efficiency of this type of device is still far lower than its theoretical conversion efficiency.Undesirable band alignment and severe non-radiative recombination at CZTSSe/CdS heterojunction interfaces are the major causes limiting the current/voltage output and overall device performance.Herein,we propose a novel two-step CdS deposition strategy to improve the quality of CZTSSe/CdS heterojunction interface and thereby improve the performance of CZTSSe solar cell.The two-step strategy includes firstly pre-deposits CdS thin layer on CZTSSe absorber layer by chemical bath deposition(CBD),followed with a mild heat treatment to facilitate element inter-diffusion,and secondly deposits an appropriate thickness of CdS layer by CBD to cover the whole surface of pre-deposited CdS and CZTSSe layers.The solar energy conversion efficiency of CZTSSe solar cells with two-step deposited CdS layer approaches to 8.76%(with an active area of about 0.19 cm2),which shows an encouraging improvement of over 87.98%or 30.16%compared to the devices with traditional CBD-deposited CdS layer without and with the mild annealing process,respectively.The performance enhancement by the two-step CdS deposition is attributed to the formation of more favorable band alignment at CZTSSe/CdS interface as well as the effective decrease in interfacial recombination paths on the basis of material and device characterizations.The two-step CdS deposition strategy is simple but effective,and should have large room to improve the quality of CZTSSe/CdS heterojunction interface and further lift up the conversion efficiency of CZTSSe solar cells.展开更多
Bandgap engineering by doping and co‐catalyst loading are two primary approaches to designing efficient photocatalysts by promoting visible‐light absorption and charge separation,respectively.Shifting of the TiO2con...Bandgap engineering by doping and co‐catalyst loading are two primary approaches to designing efficient photocatalysts by promoting visible‐light absorption and charge separation,respectively.Shifting of the TiO2conduction band edge is frequently applied to increase visible‐light absorption but also lowers the reductive properties of photo‐excited electrons.Herein,we report a visible‐light‐driven photocatalyst based on valance band edge control induced by oxygen excess defects and modification with a CuxO electron transfer co‐catalyst.The CuxO grafted oxygen‐rich TiO2microspheres were prepared by ultrasonic spray pyrolysis of the peroxotitanate precursor followed by a wet chemical impregnated treatment.We found that oxygen excess defects in TiO2shifted the valence band maximum upward and improved the visible‐light absorption.The CuxO grafted onto the surface acted as a co‐catalyst that efficiently reduced oxygen molecules to active intermediates(i.e.,O2??radial and H2O2),thus consuming the photo‐generated electrons.Consequently,the CuxO grafted oxygen‐rich TiO2microspheres achieved a photocatalytic activity respectively8.6,13.0and11.0as times high as those of oxygen‐rich TiO2,normal TiO2and CuxO grafted TiO2,for degradation of gaseous acetaldehyde under visible‐light irradiation.Our results suggest that high visible‐light photocatalytic efficiency can be achieved by combining oxygen excess defects to improve visible‐light absorption together with a CuxO electron transfer co‐catalyst.These findings provide a new approach to developing efficient heterojunction photocatalysts.展开更多
Au or other metal nanostructures have the ability to strongly quench the fluorescence of fluorophores.This feature has made AuNP-conjugates attractive for the construction of platforms for various bioanalytes to overc...Au or other metal nanostructures have the ability to strongly quench the fluorescence of fluorophores.This feature has made AuNP-conjugates attractive for the construction of platforms for various bioanalytes to overcome the limitations of small molecule fluorophores(poor solubility,long reaction time).In this paper,an ultrafast"Turn-On"fluo rescent sensor for biothiols was constructed.The sensor is based on the fluorescent resonance energy transfer(FRET)effect between the fluorophore(PN)and AuNPs,which effectively quenches the fluorescence of the fluorophore.In the presence of thiols,PN is displaced and released from AuNP surfaces,and thus,the fluorescence is rapidly restored.The sensor features appreciable water solubility and ultrafast response time(a few seconds for Cys).In addition,it exhibits high selectivity and a detection limit as low as 12 nmol/L for Hcy.Moreover,the sensor presents good biocompatibility and has been successfully applied for imaging biothiols in living cells.展开更多
The development of resistance against most of the available antibiotics has made Acinetobacter baumannii(A.baumannii)a pathogen of high risk.In this study,thirty novel berberine derivatives are rationally designed,syn...The development of resistance against most of the available antibiotics has made Acinetobacter baumannii(A.baumannii)a pathogen of high risk.In this study,thirty novel berberine derivatives are rationally designed,synthesized,and evaluated for their synergistic antibacterial activities against A.baumannii.Among them,compound 2d shows the most potent synergetic effect to aztreonam against A.baumannii,including carbapenem-resistant and extended-spectrumβ-lactamases-producing strains.Moreover,synergistic effects were observed for the combinations of 2d and different antibacterial used in clinical practices,indicating its potent broad-spectrum antibiotic-sensitizing effects against A.baumannii.The combination of 2d and aztreonam significantly improves the survival rates of G.mellonella larvae compared with aztreonam treatment alone.Mechanism studies indicate that 2d inhibits the drug efflux and iron acquisition of the bacteria by targeting the AdeB transporter protein,thus achieving a synergistic antimicrobial efficacy with different antibacterial agents.Therefore,berberine derivatives represent a new family of antimicrobial adjuvants against A.baumannii,with the advantage of dual-function antibacterial effect,and are worthy of further investigation.展开更多
The aim of this study was to investigate the role of selenoprotein M(SelM)in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin.At 21 d after ...The aim of this study was to investigate the role of selenoprotein M(SelM)in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin.At 21 d after intraperitoneal injection of nickel chloride(NiCl_(2))and/or melatonin into male wild-type(WT)and SelM knockout(KO)C57BL/6J mice,NiCl_(2)was found to induce changes in the microstructure and ultrastructure of the hearts of both WT and SelM KO mice,which were caused by oxidative stress,endoplasmic reticulum stress,and apoptosis,as evidenced by decreases in malondialdehyde(MDA)content and total antioxidant capacity(T-AOC)activity.Changes in the messenger RNA(mRNA)and protein expression of genes related to endoplasmic reticulum stress(activating transcription factor 4(ATF4),inositol-requiring protein 1(IRE1),c-Jun N-terminal kinase(JNK),and C/EBP homologous protein(CHOP))and apoptosis(B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),Caspase-3,Caspase-9,and Caspase-12)were also observed.Notably,the observed damage was worse in SelM KO mice.Furthermore,melatonin alleviated the heart injury caused by NiCl_(2)in WT mice but could not exert a good protective effect in the heart of SelM KO mice.Overall,the findings suggested that the antioxidant capacity of SelM,as well as its modulation of endoplasmic reticulum stress and apoptosis,plays important roles in nickel-induced heart injury.展开更多
Isometric exercise(IE)is a promising intervention of noninvasive revascularization in patients with acute myocardial infarction(AMI).This study aimed to investigate the impact and mechanisms of IE training on arteriog...Isometric exercise(IE)is a promising intervention of noninvasive revascularization in patients with acute myocardial infarction(AMI).This study aimed to investigate the impact and mechanisms of IE training on arteriogenesis in AMI.Male Sprague-Dawley rats were randomly assigned into the sham-operation group(SO),myocardial infarction(MI)group,and 13 IE subgroups treated according to training intensity,frequency,duration,or monocyte chemoattractant protein-1(MCP-1),or/and fibroblast growth factor-2(FGF-2)inhibitors for eight weeks.Our results demonstrated that the IE group achieved superior improvement compared with the MI group in terms of left ventricular ejection fraction(LVEF),myocardial infarction size(MIS),arterial density(AD),monocytes(MNCs),smooth muscle cells(SMCs),endothelial cells(ECs),relative collateral blood flow(RCBF),MCP-1,and FGF-2 at the endpoint.Positive correlations between MCP-1 and MNCs,MNCs and FGF-2,FGF-2 and SMCs,SMCs and AD,as well as AD and RCBF were observed.This study demonstrated that with MI of 100%load 20 times daily for eight weeks,the arteriogenesis was improved,which may be attributed to the recruitment of MNCs and SMCs in remote ischemic myocardium caused by increases in MCP-1 and FGF-2 expression.展开更多
Cardioplegia has been widely used to reduce myocardial injury during pediatric cardiac surgery;however,which cardioplegia solution has the best protective effect has not been established.Thus,we compared the myocardia...Cardioplegia has been widely used to reduce myocardial injury during pediatric cardiac surgery;however,which cardioplegia solution has the best protective effect has not been established.Thus,we compared the myocardial protective effects of different cardioplegia solutions used in pediatric cardiac surgery.Seven databases were searched to identify the relevant randomized controlled trials.A network meta-analysis with a Bayesian framework was conducted.The outcomes included the following biochemical and clinical outcomes:serum concentrations of the creatine kinase-myocardial band at 6 h postoperatively;cardiac troponin I(cTnI)at 4,12,and 24 h postoperatively;spontaneous beating after declamping;postoperative arrhythmias;inotropic support percentage and duration;mechanical ventilation hours;intensive care unit stay in days;hospital stay in days;and mortality.The group treated with cold crystalloid cardioplegia(cCCP)was chosen as the control group.The 22 studies involved 1529 patients.Six types of cardioplegia solutions were described in these studies,including cold blood cardioplegia,cCCP,del Nido,histidine-tryptophan-ketoglutarate(HTK),terminal warm blood cardioplegia,and warm blood cardioplegia(wBCP).The serum concentrations of the 24-h cTnI with wBCP(MD=−2.52,95%CI:−4.74 to−0.27)was significantly lower than cCCP.The serum concentrations of the 24-h cTnI with HTK(MD=4.91,95%CI:2.84–7.24)was significantly higher than cCCP.There was no significant difference in other biochemical and clinical outcomes when compared to cCCP.In conclusion,wBCP may have a superior myocardial protective effect with lower 24-h cTnI levels postoperatively and similar clinical outcomes after pediatric cardiac surgery.展开更多
The electron transport layer （ETL） plays an important role in planar heterojunction perovskite solar cell （PSCs）, by affecting the light-harvesting, electron injection and transportation processes, and especially ...The electron transport layer （ETL） plays an important role in planar heterojunction perovskite solar cell （PSCs）, by affecting the light-harvesting, electron injection and transportation processes, and especially the crystal- lization of perovskite absorber. In this work, we utilized a commercial TKD-TiO2 nanoparticle with a small diameter of 6 nm for the first time to prepare a compact ETL by spin coating. The packing of small-size particles endowed TKD-TiO2 ETL an appropriate surface-wettability, which is beneficial to the crystallization of perovskite deposited via solution-processed method. The uniform and high-transmittance TKD-TiO2 films were successfully incorporated into PSCs as ETLs. Further careful optimization of ETL thickness gave birth to a highest power conversion efficiency of 11.0%, which was much higher than that of PSC using an ETL with the same thickness made by spray pyrolysis. This TKD-TiO2 provided a universal solar material suitable for the further large-scale production of PSCs. The excellent morphology and the convenient preparation method of TKD-TiO2 film gave it an extensive application in photovoltaic devices.展开更多
The aim of this paper is to study the 3x + 1 problem based on the Collatz iterative formula. It can be seen from the iterative formula that the necessary condition for the Collatz iteration convergence is that its slo...The aim of this paper is to study the 3x + 1 problem based on the Collatz iterative formula. It can be seen from the iterative formula that the necessary condition for the Collatz iteration convergence is that its slope being less than 1. An odd number N that satisfies the condition of a slope less than 1 after n<sup>th</sup> Collatz iterations is defined as an n-step odd number. Through statistical analysis, it is found that after n<sup>th</sup> Collatz iterations, the iterative value of any n-step odd number N that is greater than 1 is less than N, which proves that the slope less than 1 is a sufficient and necessary condition for Collatz iteration convergence.展开更多
Harmonic mode-locking,realized actively or passively,is an effective technique for increasing the repetition rate of ultrafast lasers.It is critically important to understand how a harmonically mode-locked pulse train...Harmonic mode-locking,realized actively or passively,is an effective technique for increasing the repetition rate of ultrafast lasers.It is critically important to understand how a harmonically mode-locked pulse train responds to external perturbations and noise,so as to make sure that it is stable and resistant to noise.Here,in a series of carefully designed experiments,we elucidate the retiming dynamics of laser pulses generated in a soliton fiber laser harmonically modelocked at GHz frequencies to the acoustic resonance in a photonic crystal fiber(PCF)core.We characterize the selfdriven optomechanical lattice,which is distributed along the PCF and provides the structure that supports harmonic mode-locking,using a homodyne setup.We reveal that,after an abrupt perturbation,each soliton in the lattice undergoes damped oscillatory retiming within its trapping potential,while the retiming is strongly coupled to soliton dissipation.In addition,we show,through statistical analysis of the intra-cavity pulse spacing,how the trapping potentials are effective for suppressing timing jtter.The measurements and the theory developed in this work lay the groundwork for studies of the general stability and noise performance of harmonically mode-locked lasers as well as providing valuable insight into generic multi-pulse phenomena in mode-locked lasers.展开更多
Enhancer of Zeste homolog 2(EzH2),a histone methyltransferase within polycomb repressive complex 2(PRC2),plays a crucial role in epigenetic regulation by silencing gene expression through trimethylation of histone 3 a...Enhancer of Zeste homolog 2(EzH2),a histone methyltransferase within polycomb repressive complex 2(PRC2),plays a crucial role in epigenetic regulation by silencing gene expression through trimethylation of histone 3 at lysine 27(H3K27me3).Beyond its well-documented oncogenic functions,emerging research has revealed EZH2's involvement in various non-cancerous pathologies.For instance,EZH2 is critical in regulating immune responses,particularly in modulating T cell differentiation and cytokine production,which affects inflammation and immune homeostasis.EzH2 also controls fibroblast activation and extracellular matrix(ECM)remodeling,influencing critical processes such as cell differentiation,tissue repair and energy homeostasis.Additionally,EzH2's epigenetic regulation of neuroinflammatory processes is linked to neuronal health and survival.Recent advancements in EZH2 inhibitor therapies demonstrate promising potential for treating a range of non-cancerous conditions,with preclinical trials suggesting efficacy in mitigating disease progression.This review highlights the expanding functional scope of EZH2,emphasizing its epigenetic mechanisms and the therapeutic opportunities for targeting EZH2 in non-cancerous diseases.展开更多
Lead sulfide quantum dots(PbS QDs)are promising for near-infrared photovoltaics due to their large exciton Bohr radius and size-tunable bandgap.However,extending absorption into the near-infrared(bandgap<1.13 eV)ne...Lead sulfide quantum dots(PbS QDs)are promising for near-infrared photovoltaics due to their large exciton Bohr radius and size-tunable bandgap.However,extending absorption into the near-infrared(bandgap<1.13 eV)necessitates larger QDs,which weakens quantum confinement and lowers the conduction band(CB)energy towards bulk-like levels.This CB shift induces severe energy-level misalignment at the ZnO/QDs heterojunction interface,impeding charge extraction efficiency.Conventional dipole-based energy-level tuning strategies rely on ligands coordinated to Pb sites.However,large PbS QDs expose more non-polar(100)facets with a stoichiometric 1:1 Pb:S ratio,where traditional ligands fail to bind S sites,presenting a fundamental barrier to precise energy-level control.To address this issue,we introduce a novel approach:modulating PbS QD energy levels by inducing interfacial dipoles through direct metal cation coordination to the S sites.Systematic screening of metal salts revealed that Zn^(2+) coordination induces the most prominent dipole effect,reducing the work function(WF)of PbS QDs from 4.38 to 4.28 eV.This optimization aligns the band arrangement at the ZnO/QDs interface and facilitates efficient extraction of photogenerated electrons from the PbS absorber layer to the ZnO electron transport layer(ETL).Solar cell devices fabricated using this strategy achieved a power conversion efficiency(PCE)of 11.0%,representing a 12%relative enhancement over the control group(9.8%).展开更多
Using chemoproteomic techniques,we first identified EIF2AK2,eEF1A1,PRDX3 and VPS4B as direct targets of berberine(BBR)for its synergistically anti-inflammatory effects.Of them,BBR has the strongest affinity with EIF2A...Using chemoproteomic techniques,we first identified EIF2AK2,eEF1A1,PRDX3 and VPS4B as direct targets of berberine(BBR)for its synergistically anti-inflammatory effects.Of them,BBR has the strongest affinity with EIF2AK2 via two ionic bonds,and regulates several key inflammatory pathways through EIF2AK2,indicating the dominant role of EIF2AK2.Also,BBR could subtly inhibit the dimerization of EIF2AK2,rather than its enzyme activity,to selectively modulate its downstream pathways including JNK,NF-κB,AKT and NLRP3,with an advantage of good safety profile.In EIF2AK2 gene knockdown mice,the inhibitory IL-1β,IL-6,IL-18 and TNF-a secretion of BBR was obviously attenuated,confirming an EIF2AK2-dependent anti-inflammatory efficacy.The results highlight the BBR's network mechanism on anti-inflammatory effects in which EIF2AK2 is a key target,and inhibition of EIF2AK2 dimerization has a potential to be a therapeutic strategy against inflammationrelated disorders.展开更多
Due to its safety,convenience,low cost and good compliance,oral administration attracts lots of attention.However,the efficacy of many oral drugs is limited to their unsatisfactory bioavailability in the gastrointesti...Due to its safety,convenience,low cost and good compliance,oral administration attracts lots of attention.However,the efficacy of many oral drugs is limited to their unsatisfactory bioavailability in the gastrointestinal tract.One of the critical and most overlooked factors is the symbiotic gut microbiota that can modulate the bioavailability of oral drugs by participating in the biotransformation of oral drugs,influencing the drug transport process and altering some gastrointestinal properties.In this review,we summarized the existing research investigating the possible relationship between the gut microbiota and the bioavailability of oral drugs,which may provide great ideas and useful instructions for the design of novel drug delivery systems or the achievement of personalized medicine.展开更多
The extremely low bioavailability of oral paclitaxel(PTX)mainly due to the complicated gastrointestinal environment,the obstruction of intestinal mucus layer and epithelium barrier.Thus,it is of great significance to ...The extremely low bioavailability of oral paclitaxel(PTX)mainly due to the complicated gastrointestinal environment,the obstruction of intestinal mucus layer and epithelium barrier.Thus,it is of great significance to construct a coordinative delivery system which can overcome multiple intestinal physicochemical obstacles simultaneously.In this work,a high-density PEGylation-based glycocholic acid-decorated micelles(PTX@GNPs)was constructed by a novel polymer,9-Fluorenylmethoxy carbonyl-poly ethylene glycocholic acid(Fmoc-PEG-GCA).The Fmoc motif in this polymer could encapsulate PTX viaπ-πstacking to form the core of micelles,and the low molecular weight and non-long hydrophobic chain of Fmoc ensures the high-density of PEG.Based on this versatile and flexible carriers,PTX@GNPs possess mucus trapping escape ability due to the flexible PEG,and excellent intestine epithelium targeting attributed to the high affinity of GCA with apical sodium-dependent bile acid transporter.The in vitro and in vivo results showed that this oral micelle could enhance oral bioavailability of PTX,and exhibited similar antitumor efficacy to Taxol injection via intravenous route.In addition,oral PTX@GNPs administered with lower dosage within shorter interval could increase in vivo retention time of PTX,which supposed to remodel immune microenvironment and enhance oral chemotherapy efficacy by synergistic effect.展开更多
基金supported by the Natural Science Foundation of China(51072032,51372036,51102001)the Key Project of Chinese Ministry of Education(113020A)+1 种基金the 111 project(B13013)Jilin Province Science and Technology Development Plan(20180101175JC,20160520170JH)~~
文摘Photocatalysis shows great promise in the field of solar energy conversion.One of the reasons for this is because it promotes the development of multi-field-coupled catalysis.In order to explore the principles of multi-field-coupled catalytic reactions,an in situ multi-field-coupled characterization technique is required.In this study,we obtained hydrogenated ST-01 TiO2 and observed enhanced catalytic activity by thermal coupled photocatalysis.In situ photoconductivity was employed to understand the activity enhancement.The effects of the reaction temperature,reaction atmosphere,and oxygen vacancy(Ov)on the photoconductivity of TiO2 were studied.After coupling thermal into photoconductivity measurement,highly active Ov-TiO2 displayed rapid decay of photoconductivity in a CO2 atmosphere and slow decay of photoconductivity in a N2 atmosphere.These phenomena revealed that photothermal coupling assisted the detrapping of electrons at the Ov surface and promoted electron transfer to CO2,which clearly explained the high photothermal catalytic activity of Ov-TiO2.This study demonstrated that photoconductivity is a useful tool to help understand photothermal catalytic phenomena.
文摘Semiconductor oxides are widely used to achieve photocatalytic removal of NOx(NO and NO2) species. These materials also exhibit enhanced oxidation ability in thermally assisted photocatalysis;however, many of them tend to be deactivated at high relative humidity(RH) levels. In the case of the benchmark P25 TiO2 photocatalyst, we observe a significant decrease in non-NO2 selectivity from 95.02% to 58.33% when RH increases from 20% to 80%. Interestingly, the porous TiO2(B) microspheres synthesized in this work exhibit 99% selectivity at 20% RH;the selectivity remains as high as 96.18% at 80% RH. The high humidity tolerance of the TiO2(B) sample can be ascribed to its strong water desorption capacity and easy O2 adsorption at elevated temperatures, which reflects the fact that the superoxide radical is the main active species for the deep oxidation of NOx. This work may inspire the design of efficient photothermal catalysts with application in NOx removal in hot and humid environments.
基金supported by the National Key R&D Program of China (2021YFA0716404)the National Natural Science Foundation of China (51872043,51732003,11974129)+1 种基金the“111”project (B13013)the Jilin Province Development and Reform Commission (2022C040-1)。
文摘Perovskite solar cells(PSCs)have been developed over the past decade as the forefront of the state-of-theart photovoltaic technologies owing to their high efficiency and low cost,where nanostructured functional materials play key roles in performance optimization.As a versatile class of two-dimensional(2D)materials,transition metal carbides/nitrides MXenes have gained enormous attentions in PSCs since 2018 due to their superior properties such as excellent metallic conductivity,abundant surface functional groups,tunable work functions,high optical transparency,and mechanical robustness.The explorations of MXenes are of significance in performance promotion and commercialization expansion of devices.As such,this review focuses on the diversified advantages of MXenes,comprehensively summarizing their applications and developments in PSCs as additives,electron/hole transporting layers,interfacial engineering layers,and electrodes in sequence and explaining the relevant mechanisms behind.Simultaneously,the problems emerged from the related studies are considered and the corresponding suggestions like opening up the type of MXenes usage,taking further insight of the modulation of surface termination groups on Fermi levels,understanding the effect on energy level structures of perovskite or other functional layers,and realizing commercialization,etc.are provided for the future in-depth explorations.This review is intended to provide overall perspective of the current status of MXenes and highlight the direction for the future advancements in MXenes design and processes towards efficient,stable,large-area,and low-cost PSCs.
基金supported by the National Natural Science Foundation of China(91833303,51872044,51372036,51202025 and 51602047)the Key Project of Chinese Ministry of Education(113020A)+3 种基金the 111 project(B13013)the Jilin Province Science and Technology Development Project(20180101175JC and 20140520096JH)the Fundamental Research Funds for the Central Universities(2412019FZ043)the Open Project of Key Laboratory for UV Emitting Materials and Technology of Ministry of Education(130028857).
文摘Kesterite Cu2ZnSn(S,Se)4(CZTSSe)solar cells have drawn worldwide attention for their promising photovoltaics performance and earth-abundant element composition,yet the record efficiency of this type of device is still far lower than its theoretical conversion efficiency.Undesirable band alignment and severe non-radiative recombination at CZTSSe/CdS heterojunction interfaces are the major causes limiting the current/voltage output and overall device performance.Herein,we propose a novel two-step CdS deposition strategy to improve the quality of CZTSSe/CdS heterojunction interface and thereby improve the performance of CZTSSe solar cell.The two-step strategy includes firstly pre-deposits CdS thin layer on CZTSSe absorber layer by chemical bath deposition(CBD),followed with a mild heat treatment to facilitate element inter-diffusion,and secondly deposits an appropriate thickness of CdS layer by CBD to cover the whole surface of pre-deposited CdS and CZTSSe layers.The solar energy conversion efficiency of CZTSSe solar cells with two-step deposited CdS layer approaches to 8.76%(with an active area of about 0.19 cm2),which shows an encouraging improvement of over 87.98%or 30.16%compared to the devices with traditional CBD-deposited CdS layer without and with the mild annealing process,respectively.The performance enhancement by the two-step CdS deposition is attributed to the formation of more favorable band alignment at CZTSSe/CdS interface as well as the effective decrease in interfacial recombination paths on the basis of material and device characterizations.The two-step CdS deposition strategy is simple but effective,and should have large room to improve the quality of CZTSSe/CdS heterojunction interface and further lift up the conversion efficiency of CZTSSe solar cells.
基金supported by the National Natural Science Foundation of China(51072032,51372036,51702235)~~
文摘Bandgap engineering by doping and co‐catalyst loading are two primary approaches to designing efficient photocatalysts by promoting visible‐light absorption and charge separation,respectively.Shifting of the TiO2conduction band edge is frequently applied to increase visible‐light absorption but also lowers the reductive properties of photo‐excited electrons.Herein,we report a visible‐light‐driven photocatalyst based on valance band edge control induced by oxygen excess defects and modification with a CuxO electron transfer co‐catalyst.The CuxO grafted oxygen‐rich TiO2microspheres were prepared by ultrasonic spray pyrolysis of the peroxotitanate precursor followed by a wet chemical impregnated treatment.We found that oxygen excess defects in TiO2shifted the valence band maximum upward and improved the visible‐light absorption.The CuxO grafted onto the surface acted as a co‐catalyst that efficiently reduced oxygen molecules to active intermediates(i.e.,O2??radial and H2O2),thus consuming the photo‐generated electrons.Consequently,the CuxO grafted oxygen‐rich TiO2microspheres achieved a photocatalytic activity respectively8.6,13.0and11.0as times high as those of oxygen‐rich TiO2,normal TiO2and CuxO grafted TiO2,for degradation of gaseous acetaldehyde under visible‐light irradiation.Our results suggest that high visible‐light photocatalytic efficiency can be achieved by combining oxygen excess defects to improve visible‐light absorption together with a CuxO electron transfer co‐catalyst.These findings provide a new approach to developing efficient heterojunction photocatalysts.
基金the support from the National Natural Science Foundation of China(Nos.81971678 and 81671756)Key Research Project of Science and Technology Foundation of Hunan Province(Nos.2017SK2093,2018GK5004 and 2019SK2211)Projects of Medical and Health Technology Development Program in Shandong Province(No.2018WS471)。
文摘Au or other metal nanostructures have the ability to strongly quench the fluorescence of fluorophores.This feature has made AuNP-conjugates attractive for the construction of platforms for various bioanalytes to overcome the limitations of small molecule fluorophores(poor solubility,long reaction time).In this paper,an ultrafast"Turn-On"fluo rescent sensor for biothiols was constructed.The sensor is based on the fluorescent resonance energy transfer(FRET)effect between the fluorophore(PN)and AuNPs,which effectively quenches the fluorescence of the fluorophore.In the presence of thiols,PN is displaced and released from AuNP surfaces,and thus,the fluorescence is rapidly restored.The sensor features appreciable water solubility and ultrafast response time(a few seconds for Cys).In addition,it exhibits high selectivity and a detection limit as low as 12 nmol/L for Hcy.Moreover,the sensor presents good biocompatibility and has been successfully applied for imaging biothiols in living cells.
基金supported by grants from National Natural Science Foundation of China(Nos.32141003,82104013)CAMS Initiative for Innovative Medicine(Nos.2021-1-I2M-070,2021-1-I2M-039,China)。
文摘The development of resistance against most of the available antibiotics has made Acinetobacter baumannii(A.baumannii)a pathogen of high risk.In this study,thirty novel berberine derivatives are rationally designed,synthesized,and evaluated for their synergistic antibacterial activities against A.baumannii.Among them,compound 2d shows the most potent synergetic effect to aztreonam against A.baumannii,including carbapenem-resistant and extended-spectrumβ-lactamases-producing strains.Moreover,synergistic effects were observed for the combinations of 2d and different antibacterial used in clinical practices,indicating its potent broad-spectrum antibiotic-sensitizing effects against A.baumannii.The combination of 2d and aztreonam significantly improves the survival rates of G.mellonella larvae compared with aztreonam treatment alone.Mechanism studies indicate that 2d inhibits the drug efflux and iron acquisition of the bacteria by targeting the AdeB transporter protein,thus achieving a synergistic antimicrobial efficacy with different antibacterial agents.Therefore,berberine derivatives represent a new family of antimicrobial adjuvants against A.baumannii,with the advantage of dual-function antibacterial effect,and are worthy of further investigation.
基金supported by the Heilongjiang Provincial Natural Science Foundation for Outstanding Youth(No.YQ2021C021),China。
文摘The aim of this study was to investigate the role of selenoprotein M(SelM)in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin.At 21 d after intraperitoneal injection of nickel chloride(NiCl_(2))and/or melatonin into male wild-type(WT)and SelM knockout(KO)C57BL/6J mice,NiCl_(2)was found to induce changes in the microstructure and ultrastructure of the hearts of both WT and SelM KO mice,which were caused by oxidative stress,endoplasmic reticulum stress,and apoptosis,as evidenced by decreases in malondialdehyde(MDA)content and total antioxidant capacity(T-AOC)activity.Changes in the messenger RNA(mRNA)and protein expression of genes related to endoplasmic reticulum stress(activating transcription factor 4(ATF4),inositol-requiring protein 1(IRE1),c-Jun N-terminal kinase(JNK),and C/EBP homologous protein(CHOP))and apoptosis(B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),Caspase-3,Caspase-9,and Caspase-12)were also observed.Notably,the observed damage was worse in SelM KO mice.Furthermore,melatonin alleviated the heart injury caused by NiCl_(2)in WT mice but could not exert a good protective effect in the heart of SelM KO mice.Overall,the findings suggested that the antioxidant capacity of SelM,as well as its modulation of endoplasmic reticulum stress and apoptosis,plays important roles in nickel-induced heart injury.
基金supported by the research grants from the National Natural Science Foundation of China(Grant No.8177244,No.81902288,and No.82072546)Nanjing Municipal Science and Technology Bureau(Grant No.2019060002).
文摘Isometric exercise(IE)is a promising intervention of noninvasive revascularization in patients with acute myocardial infarction(AMI).This study aimed to investigate the impact and mechanisms of IE training on arteriogenesis in AMI.Male Sprague-Dawley rats were randomly assigned into the sham-operation group(SO),myocardial infarction(MI)group,and 13 IE subgroups treated according to training intensity,frequency,duration,or monocyte chemoattractant protein-1(MCP-1),or/and fibroblast growth factor-2(FGF-2)inhibitors for eight weeks.Our results demonstrated that the IE group achieved superior improvement compared with the MI group in terms of left ventricular ejection fraction(LVEF),myocardial infarction size(MIS),arterial density(AD),monocytes(MNCs),smooth muscle cells(SMCs),endothelial cells(ECs),relative collateral blood flow(RCBF),MCP-1,and FGF-2 at the endpoint.Positive correlations between MCP-1 and MNCs,MNCs and FGF-2,FGF-2 and SMCs,SMCs and AD,as well as AD and RCBF were observed.This study demonstrated that with MI of 100%load 20 times daily for eight weeks,the arteriogenesis was improved,which may be attributed to the recruitment of MNCs and SMCs in remote ischemic myocardium caused by increases in MCP-1 and FGF-2 expression.
文摘Cardioplegia has been widely used to reduce myocardial injury during pediatric cardiac surgery;however,which cardioplegia solution has the best protective effect has not been established.Thus,we compared the myocardial protective effects of different cardioplegia solutions used in pediatric cardiac surgery.Seven databases were searched to identify the relevant randomized controlled trials.A network meta-analysis with a Bayesian framework was conducted.The outcomes included the following biochemical and clinical outcomes:serum concentrations of the creatine kinase-myocardial band at 6 h postoperatively;cardiac troponin I(cTnI)at 4,12,and 24 h postoperatively;spontaneous beating after declamping;postoperative arrhythmias;inotropic support percentage and duration;mechanical ventilation hours;intensive care unit stay in days;hospital stay in days;and mortality.The group treated with cold crystalloid cardioplegia(cCCP)was chosen as the control group.The 22 studies involved 1529 patients.Six types of cardioplegia solutions were described in these studies,including cold blood cardioplegia,cCCP,del Nido,histidine-tryptophan-ketoglutarate(HTK),terminal warm blood cardioplegia,and warm blood cardioplegia(wBCP).The serum concentrations of the 24-h cTnI with wBCP(MD=−2.52,95%CI:−4.74 to−0.27)was significantly lower than cCCP.The serum concentrations of the 24-h cTnI with HTK(MD=4.91,95%CI:2.84–7.24)was significantly higher than cCCP.There was no significant difference in other biochemical and clinical outcomes when compared to cCCP.In conclusion,wBCP may have a superior myocardial protective effect with lower 24-h cTnI levels postoperatively and similar clinical outcomes after pediatric cardiac surgery.
基金supported by the Natural Science Foundation of China(grant no.91233204,51372036 and 51102001)the Key Project of Chinese Ministry of Education(no.113020A)+4 种基金the Specialized Research Fund for the Doctoral Program of Higher Education(20120043110002)the National Basic Research Program(2012CB933703)the 111 project(no.B13013)the International Science & Technology Cooperation Program of China(2013DFG50150)the Fundamental Research Funds for the Central Universities(2412015KJ010 and 14ZZ1510)
文摘The electron transport layer （ETL） plays an important role in planar heterojunction perovskite solar cell （PSCs）, by affecting the light-harvesting, electron injection and transportation processes, and especially the crystal- lization of perovskite absorber. In this work, we utilized a commercial TKD-TiO2 nanoparticle with a small diameter of 6 nm for the first time to prepare a compact ETL by spin coating. The packing of small-size particles endowed TKD-TiO2 ETL an appropriate surface-wettability, which is beneficial to the crystallization of perovskite deposited via solution-processed method. The uniform and high-transmittance TKD-TiO2 films were successfully incorporated into PSCs as ETLs. Further careful optimization of ETL thickness gave birth to a highest power conversion efficiency of 11.0%, which was much higher than that of PSC using an ETL with the same thickness made by spray pyrolysis. This TKD-TiO2 provided a universal solar material suitable for the further large-scale production of PSCs. The excellent morphology and the convenient preparation method of TKD-TiO2 film gave it an extensive application in photovoltaic devices.
文摘The aim of this paper is to study the 3x + 1 problem based on the Collatz iterative formula. It can be seen from the iterative formula that the necessary condition for the Collatz iteration convergence is that its slope being less than 1. An odd number N that satisfies the condition of a slope less than 1 after n<sup>th</sup> Collatz iterations is defined as an n-step odd number. Through statistical analysis, it is found that after n<sup>th</sup> Collatz iterations, the iterative value of any n-step odd number N that is greater than 1 is less than N, which proves that the slope less than 1 is a sufficient and necessary condition for Collatz iteration convergence.
基金supported by the National Natural Science Foundation of China(Grant No.62375275 and 62275254)by Strategic Priority Research Program of the Chinese Academy of Science(XDB0650000)+1 种基金by Shanghai Science and Technology Plan Project Funding(Grant No.23JC1410100)by Fuyang High-level Talent Group Project.
文摘Harmonic mode-locking,realized actively or passively,is an effective technique for increasing the repetition rate of ultrafast lasers.It is critically important to understand how a harmonically mode-locked pulse train responds to external perturbations and noise,so as to make sure that it is stable and resistant to noise.Here,in a series of carefully designed experiments,we elucidate the retiming dynamics of laser pulses generated in a soliton fiber laser harmonically modelocked at GHz frequencies to the acoustic resonance in a photonic crystal fiber(PCF)core.We characterize the selfdriven optomechanical lattice,which is distributed along the PCF and provides the structure that supports harmonic mode-locking,using a homodyne setup.We reveal that,after an abrupt perturbation,each soliton in the lattice undergoes damped oscillatory retiming within its trapping potential,while the retiming is strongly coupled to soliton dissipation.In addition,we show,through statistical analysis of the intra-cavity pulse spacing,how the trapping potentials are effective for suppressing timing jtter.The measurements and the theory developed in this work lay the groundwork for studies of the general stability and noise performance of harmonically mode-locked lasers as well as providing valuable insight into generic multi-pulse phenomena in mode-locked lasers.
基金supported by grant 2022YFA1104001 from the National Key Research and Development Program of ChinaGrants Nos.82272745,81972966,82203433,82404099 and 82404113 from the National Natural Science Foundation of China+2 种基金grants BYSYZD2023010(to LXX),BYSY2022070(to YQW),BYSYZD2023041(to JLZ)and BYSYRCYJ2023004(to JLZ)from Peking University Third Hospital Clinical Key Projectgrant 2023A1515111068 from Basic and Applied Basic Research Foundation of Guangdong Provincegrant JCYJ20230807095121041 from Shenzhen Science and Technology Program.
文摘Enhancer of Zeste homolog 2(EzH2),a histone methyltransferase within polycomb repressive complex 2(PRC2),plays a crucial role in epigenetic regulation by silencing gene expression through trimethylation of histone 3 at lysine 27(H3K27me3).Beyond its well-documented oncogenic functions,emerging research has revealed EZH2's involvement in various non-cancerous pathologies.For instance,EZH2 is critical in regulating immune responses,particularly in modulating T cell differentiation and cytokine production,which affects inflammation and immune homeostasis.EzH2 also controls fibroblast activation and extracellular matrix(ECM)remodeling,influencing critical processes such as cell differentiation,tissue repair and energy homeostasis.Additionally,EzH2's epigenetic regulation of neuroinflammatory processes is linked to neuronal health and survival.Recent advancements in EZH2 inhibitor therapies demonstrate promising potential for treating a range of non-cancerous conditions,with preclinical trials suggesting efficacy in mitigating disease progression.This review highlights the expanding functional scope of EZH2,emphasizing its epigenetic mechanisms and the therapeutic opportunities for targeting EZH2 in non-cancerous diseases.
基金supported by Jilin Provincial Scientific and Technological Development Program(No.20230101110JC)the National Natural Science Foundation of China(Nos.62074031,52273236,51872044,and U22A2078)the 111 Project(No.B25030).
文摘Lead sulfide quantum dots(PbS QDs)are promising for near-infrared photovoltaics due to their large exciton Bohr radius and size-tunable bandgap.However,extending absorption into the near-infrared(bandgap<1.13 eV)necessitates larger QDs,which weakens quantum confinement and lowers the conduction band(CB)energy towards bulk-like levels.This CB shift induces severe energy-level misalignment at the ZnO/QDs heterojunction interface,impeding charge extraction efficiency.Conventional dipole-based energy-level tuning strategies rely on ligands coordinated to Pb sites.However,large PbS QDs expose more non-polar(100)facets with a stoichiometric 1:1 Pb:S ratio,where traditional ligands fail to bind S sites,presenting a fundamental barrier to precise energy-level control.To address this issue,we introduce a novel approach:modulating PbS QD energy levels by inducing interfacial dipoles through direct metal cation coordination to the S sites.Systematic screening of metal salts revealed that Zn^(2+) coordination induces the most prominent dipole effect,reducing the work function(WF)of PbS QDs from 4.38 to 4.28 eV.This optimization aligns the band arrangement at the ZnO/QDs interface and facilitates efficient extraction of photogenerated electrons from the PbS absorber layer to the ZnO electron transport layer(ETL).Solar cell devices fabricated using this strategy achieved a power conversion efficiency(PCE)of 11.0%,representing a 12%relative enhancement over the control group(9.8%).
基金the CAMS initiative for innovative medicine(2022-I2M-2-002,China)National Natural Science Foundation of China(32141003)。
文摘Using chemoproteomic techniques,we first identified EIF2AK2,eEF1A1,PRDX3 and VPS4B as direct targets of berberine(BBR)for its synergistically anti-inflammatory effects.Of them,BBR has the strongest affinity with EIF2AK2 via two ionic bonds,and regulates several key inflammatory pathways through EIF2AK2,indicating the dominant role of EIF2AK2.Also,BBR could subtly inhibit the dimerization of EIF2AK2,rather than its enzyme activity,to selectively modulate its downstream pathways including JNK,NF-κB,AKT and NLRP3,with an advantage of good safety profile.In EIF2AK2 gene knockdown mice,the inhibitory IL-1β,IL-6,IL-18 and TNF-a secretion of BBR was obviously attenuated,confirming an EIF2AK2-dependent anti-inflammatory efficacy.The results highlight the BBR's network mechanism on anti-inflammatory effects in which EIF2AK2 is a key target,and inhibition of EIF2AK2 dimerization has a potential to be a therapeutic strategy against inflammationrelated disorders.
基金supported by Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2017-I2M1e011,China)the Drug Innovation Major Project(2018ZX09711001-002-005,China)+1 种基金National Natural Science Foundation of China(No.82073778,China)the Fundamental Research Funds for the Central Public Welfare Research Institutes(2018PT35002,China)
文摘Due to its safety,convenience,low cost and good compliance,oral administration attracts lots of attention.However,the efficacy of many oral drugs is limited to their unsatisfactory bioavailability in the gastrointestinal tract.One of the critical and most overlooked factors is the symbiotic gut microbiota that can modulate the bioavailability of oral drugs by participating in the biotransformation of oral drugs,influencing the drug transport process and altering some gastrointestinal properties.In this review,we summarized the existing research investigating the possible relationship between the gut microbiota and the bioavailability of oral drugs,which may provide great ideas and useful instructions for the design of novel drug delivery systems or the achievement of personalized medicine.
基金supported by grants from National Natural Science Foundation of China(No.82073778,China)CAMS Innovation Fund for Medical Sciences(CIFMS)(2021-I2M-1-026,China)+1 种基金Beijing Key Laboratory of Non-Clinical Drug Metabolism and PK/PD study(Z141102004414062,China)National Natural Science Foundation of China(No.82104106)。
文摘The extremely low bioavailability of oral paclitaxel(PTX)mainly due to the complicated gastrointestinal environment,the obstruction of intestinal mucus layer and epithelium barrier.Thus,it is of great significance to construct a coordinative delivery system which can overcome multiple intestinal physicochemical obstacles simultaneously.In this work,a high-density PEGylation-based glycocholic acid-decorated micelles(PTX@GNPs)was constructed by a novel polymer,9-Fluorenylmethoxy carbonyl-poly ethylene glycocholic acid(Fmoc-PEG-GCA).The Fmoc motif in this polymer could encapsulate PTX viaπ-πstacking to form the core of micelles,and the low molecular weight and non-long hydrophobic chain of Fmoc ensures the high-density of PEG.Based on this versatile and flexible carriers,PTX@GNPs possess mucus trapping escape ability due to the flexible PEG,and excellent intestine epithelium targeting attributed to the high affinity of GCA with apical sodium-dependent bile acid transporter.The in vitro and in vivo results showed that this oral micelle could enhance oral bioavailability of PTX,and exhibited similar antitumor efficacy to Taxol injection via intravenous route.In addition,oral PTX@GNPs administered with lower dosage within shorter interval could increase in vivo retention time of PTX,which supposed to remodel immune microenvironment and enhance oral chemotherapy efficacy by synergistic effect.
