This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operatin...This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operating principle for hydrogen fuel cells to establish forced circulation of the hydrogen mixture as an alternative to natural circulation(as is not utilized in conventional passive autocatalytic hydrogen recombiners currently used in nuclear power plants(NPPs)).The proposed concept of applying the physical operation principles of a PEHR based on a fuel cell simultaneously increases both productivity in terms of recombined hydrogen and the concentration threshold of flameless operation(the‘ignition’limit).Thus,it is possible to reliably ensure the hydrogen explosion safety of NPPs under all conditions,including beyond-design accidents.An experimental setup was assembled to test a laboratory sample of a membrane electrode assembly(MEA)at various hydrogen concentrations near the catalytic surfaces of the electrodes,and the corresponding current–voltage characteristics were recorded.The simplest MEA based on the Advent P1100W PBI membrane demonstrated stable performance(delivery of electrical power)over a wide range of hydrogen concentrations.展开更多
In order to reduce the curing temperature, shorten the curing time of phenol-formaldehyde(PF) resin adhesive, and ensure the good water-solubility, NaOH and Ba(OH)_2 were used as compound catalysts. The influences of ...In order to reduce the curing temperature, shorten the curing time of phenol-formaldehyde(PF) resin adhesive, and ensure the good water-solubility, NaOH and Ba(OH)_2 were used as compound catalysts. The influences of the adding time of Ba(OH)_2, the adding amount of NaOH, Ba(OH)_2 and resorcinol on the properties of adhesives were studied. The properties of NaOH catalyzed phenol-formaldehyde(PF) adhesive, NaOH and Ba(OH)_2 compound catalyzed PF adhesive, NaOH and Ba(OH)_2 compound catalyzed phenol-resorcinol-formaldehyde(PRF) adhesive, and the prepared recombinant bamboo with three kinds of adhesives were compared. The experimental results show that NaOH and Ba(OH)_2 compound catalyst not only shortens the curing time of PF adhesive, but also guarantees the suitable water solubility of adhesive. After copolycondensation with resorcinol, the curing time of adhesive is further shortened, the water solubility is improved obviously, and the highest bonding strength is obtained. Infrared spectrum analysis shows that the reaction activity point of NaOH and Ba(OH)_2 compound catalyzed PRF adhesive will increase, so that both the curing temperature and curing enthalpy decrease.展开更多
The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokin...The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokinetics, the determination of metabolic principles, and evaluation of treatment effect. The objective of the study was to investigate the pharmacokinetic characteristics of gene recombination angiogenesis inhibitor Kringle 5 in vivo. The SPECT/CT and specific^(131)I-Kringle 5 marked by Iodogen method were both applied to explore the pharmacokinetic characteristics of^(131)I-Kringle 5 in vivo, and to investigate the dynamic distributions of^(131)I-Kringle 5 in target organs. Labeling recombinant angiogenesis inhibitor Kringle 5 using131 I with longer half-life and imaging in vivo using SPECT instead of PET,could overcome the limitations of previous methods. When the doses of^(131)I-Kringle 5 were 10.0, 7.5 and5.0 g/kg, respectively, the two-compartment open models can be determined within all the metabolic process in vivo. There were no significant differences in t1/2α, t1/2β, apparent volume of distribution and CL between those three levels. The ratio of AUC(0 1)among three different groups of 10.0, 7.5 and 5.0 g/kg was 2.56:1.44:1.0, which was close to the ratio(2:1.5:1.0). It could be clear that in the range of 5.0–10.0 g/kg, Kringle 5 was characterized by the first-order pharmacokinetics. Approximately 30 min after^(131)I-Kringle 5 was injected,^(131)I-Kringle 5 could be observed to concentrate in the heart, kidneys, liver and other organs by means of planar imaging and tomography. After 1 h of being injected, more radionuclide retained in the bladder, but not in intestinal. It could be concluded that^(131)I-Kringle 5 is mainly excreted through the kidneys. About 2 h after the injection of^(131)I-Kringle 5, the radionuclide in the heart, kidneys,liver and other organs was gradually reduced, while more radionuclide was concentrated in the bladder.The radionuclide was completely metabolized within 24 h, and the distribution of radioactivity in rats was similar to normal levels. In our study, the specific marker^(131)I-Kringle 5 and SPECT/CT were successfully used to explore pharmacokinetic characteristics of Kringle 5 in rats. The study could provide a new evaluation platform of the specific, in vivo and real-time functional imaging and pharmacokinetics for the clinical application of^(131)I-Kringle 5.展开更多
Recombineering is an essential tool for molecular biologists,allowing for the facile and efficient manipulation of bacterial genomes directly in cells without the need for costly and laborious in vitro manipulations i...Recombineering is an essential tool for molecular biologists,allowing for the facile and efficient manipulation of bacterial genomes directly in cells without the need for costly and laborious in vitro manipulations involving restriction enzymes.The main workhorses behind recombineering are bacteriophage proteins that promote the single-strand annealing(SSA)homologous recombination pathway to repair double-stranded DNA breaks.While there have been several reviews examining recombineering methods and applications,comparatively few have focused on the mechanisms of the proteins that are the key players in the SSA pathway:a 5′→3′exonuclease and a single-strand annealing protein(SSAP or“annealase”).This review dives into the structures and functions of the two SSA recombination systems that were the first to be developed for recombineering in E.coli:the RecET system from E.coli Rac prophage and the𝜆Red system from bacteriophageλ.By comparing the structures of the RecT and Red𝛽annealases,and the RecE and𝜆Exo exonucleases,we provide new insights into how the structures of these proteins dictate their function.Examining the sequence conservation of the𝜆λExo and RecE exonucleases gives more profound insights into their critical functional features.Ultimately,as recombineering accelerates and evolves in the laboratory,a better understanding of the mechanisms of the proteins behind this powerful technique will drive the development of improved and expanded capabilities in the future.展开更多
Adenoviruses typically cause mild illnesses,but severe diseases may occur primarily in immunodeficient individuals,particularly children.Recently,adenoviruses have garnered significant interest as a versatile tool in ...Adenoviruses typically cause mild illnesses,but severe diseases may occur primarily in immunodeficient individuals,particularly children.Recently,adenoviruses have garnered significant interest as a versatile tool in gene therapy,tumor treatment,and vaccine vector development.Over the past two decades,the advent of recombineering,a method based on homologous recombination,has notably enhanced the utility of adenoviral vectors in therapeutic applications.This review summarizes recent advancements in the use of human adenoviral vectors in medicine and discusses the pivotal role of recombineering in the development of these vectors.Additionally,it highlights the current achievements and potential future impact of therapeutic adenoviral vectors.展开更多
Recombineering is a valuable technique for generating recombinant DNA in vivo,primarily in bacterial cells,and is based on homologous recombination using phage-encoded homologous recombinases,such as Red βγ from the...Recombineering is a valuable technique for generating recombinant DNA in vivo,primarily in bacterial cells,and is based on homologous recombination using phage-encoded homologous recombinases,such as Red βγ from the lambda phage and RecET from the Rac prophage.The recombineering technique can efficiently mediate homol-ogous recombination using short homologous arms(∼50 bp)and is unlimited by the size of the DNA molecules or positions of restriction sites.In this review,we summarize characteristics of recombinases,mechanism of recombineering,and advances in recombineering for DNA manipulation in Escherichia coli and other bacteria.Furthermore,the broad applications of recombineering for mining new bioactive microbial natural products,and for viral mutagenesis,phage genome engineering,and understanding bacterial metabolism are also reviewed.展开更多
Iron is essential for bacterial survival,and most bacteria capture iron by producing siderophores.Burkholde-riales bacteria produce various types of bioactive secondary metabolites,such as ornibactin and malleobactin ...Iron is essential for bacterial survival,and most bacteria capture iron by producing siderophores.Burkholde-riales bacteria produce various types of bioactive secondary metabolites,such as ornibactin and malleobactin siderophores.In this study,the genome analysis of Burkholderiales genomes showed a putative novel siderophore gene cluster crb,which is highly similar to the ornibactin and malleobactin gene clusters but does not have pvdF,a gene encoding a formyltransferase for N-δ-hydroxy-ornithine formylation.Establishing the bacteriophage recom-binase Redγ-Redδβ7029 mediated genome editing system in a non-model Burkholderiales strain Paraburkholderia caribensis CICC 10960 allowed the rapid identification of the products of crb gene cluster,caribactins A-F(1-6).Caribactins contain a special amino acid residue N-δ-hydroxy-N-δ-acetylornithine(haOrn),which differs from the counterpart N-δ-hydroxy-N-δ-formylornithine(hOrn)in ornibactin and malleobactin,owing to the absence of pvdF.Gene inactivation showed that the acetylation of hOrn is catalyzed by CrbK,whose homologs proba-bly not be involved in the biosynthesis of ornibactin and malleobactin,showing possible evolutionary clues of these siderophore biosynthetic pathways from different genera.Caribactins promote biofilm production and en-hance swarming and swimming abilities,suggesting that they may play crucial roles in biofilm formation.This study also revealed that recombineering has the capability to mine novel secondary metabolites from non-model Burkholderiales species.展开更多
Bacillus subtilis plays an important role in fundamental and applied research,and it has been widely used as a cell factory for the production of enzymes,antimicrobial materials,and chemicals for agriculture,medicine,...Bacillus subtilis plays an important role in fundamental and applied research,and it has been widely used as a cell factory for the production of enzymes,antimicrobial materials,and chemicals for agriculture,medicine,and industry.However,genetic manipulation tools for B.subtilis have low efficiency.In this work,our goal was to develop a simple recombineering system for B.subtilis.We showed that genome editing can be achieved in B.subtiliis 1A751 through co-expression of YqaJ/YqaK,a native phage recombinase pair found in B.sub-tilis 168,and the competence master regulator ComK using a double-stranded DNA substrate with short ho-mology arms(100 bp)and a phosphorothioate modification at the 5′-end.Efficient gene knockouts and large DNA insertions were achieved using this new recombineering system in B.subtilis 1A751.As far as we know,this is the first recombineering system using the native phage recombinase pair YqaJ/YqaK in B.subtilis.In conclusion,this new recombineering system provides a simple and fast tool for genetic manipulation of B.sub-tilis,and it will promote studies of genome function,construction of production strains,and genome mining in B.subtilis.展开更多
Hydrogen challenge mitigation stands as one of the main objectives in the management of severe accidents at Nuclear Power Plants (NPPs). Key strategies for hydrogen control include atmospheric inertization and hydroge...Hydrogen challenge mitigation stands as one of the main objectives in the management of severe accidents at Nuclear Power Plants (NPPs). Key strategies for hydrogen control include atmospheric inertization and hydrogen removal with Passive Autocatalytic Recombiners (PARs) being a commonly accepted approach. However, an examination of PAR operation specificity reveals potential inefficiencies and reliability issues in certain severe accident scenarios. Moreover, during the in-vessel stage of severe accident development, in some severe accident scenarios PARs can unexpectedly become a source of hydrogen detonation. The effectiveness of hydrogen removal systems depends on various factors, including the chosen strategies, severe accident scenarios, reactor building design, and other influencing factors. Consequently, a comprehensive hydrogen mitigation strategy must effectively incorporate a combination of strategies rather than be based on one strategy, taking into consideration the probabilistic risks and uncertainties associated with the implementation of PARs or other traditional methods. In response to these considerations, within the framework of this research it has been suggested a conceptual strategy to mitigate the hydrogen challenge during the in-vessel stage of severe accident development.展开更多
Genome engineering of Rhodococcus opacus PD630,an important microorganism used for the bioconversion of lignin,is currently dependent on inefficient homologous recombination.Although a CRISPR interference procedure fo...Genome engineering of Rhodococcus opacus PD630,an important microorganism used for the bioconversion of lignin,is currently dependent on inefficient homologous recombination.Although a CRISPR interference procedure for gene repression has previously been developed for R.opacus PD630,a CRISPR/Cas9 system for gene knockout has yet to be reported for the strain.In this study,we found that the cytotoxicity of Cas9 and the deficiency in pathways for repairing DNA double-strand breaks(DSBs)were the major causes of the failure of conventional CRISPR/Cas9 technologies in R.opacus,even when augmented with the recombinases Che9c60 and Che9c61.We successfully developed an efficient single-stranded DNA(ssDNA)recombineering system coupled with CRISPR/Cas9 counter-selection,which facilitated rapid and scarless editing of the R.opacus genome.A two-plasmid system,comprising Cas9 driven by a weak Rhodococcus promoter Pniami,designed to prevent cytotoxicity,and a single-guide RNA(sgRNA)under the control of a strong constitutive promoter,was proven to be appropriate with respect to cleavage function.A novel recombinase,RrRecT derived from a Rhodococcus ruber prophage,was identified for the first time,which facilitated recombination of short ssDNA donors(40-80 nt)targeted to the lagging strand and enabled us to obtain a recombination efficiency up to 103-fold higher than that of endogenous pathways.Finally,by incorporating RrRecT and Cas9 into a single plasmid and then co-transforming cells with sgRNA plasmids and short ssDNA donors,we efficiently achieved gene disruption and base mutation in R.opacus,with editing efficiencies ranging from 22%to 100%.Simultaneous disruption of double genes was also confirmed,although at a lower efficiency.This effective genome editing tool will accelerate the engineering of R.opacus metabolism.展开更多
The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and stability.However,a comprehensive manipulation of the buried interface in terms of...The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and stability.However,a comprehensive manipulation of the buried interface in terms of the transport layer,buried interlayer,and perovskite layer has been largely overlooked.Herein,we propose the use of a volatile heterocyclic compound called 2-thiopheneacetic acid(TPA)as a pre-buried additive in the buried interface to achieve cross-layer all-interface defect passivation through an in situ bottom-up infiltration diffusion strategy.TPA not only suppresses the serious interfacial nonradiative recombination losses by precisely healing the interfacial and underlying defects but also effectively enhances the quality of perovskite film and releases the residual strain of perovskite film.Owing to this versatility,TPA-tailored CsPbBr3 PSCs deliver a record efficiency of 11.23% with enhanced long-term stability.This breakthrough in manipulating the buried interface using TPA opens new avenues for further improving the performance and reliability of PSC.展开更多
Inverted perovskite solar cells(PSCs) have attracted broad research and industrial interest owing to their suppressed hysteresis,cost-effectiveness,and easy-fabrication.However,the issue of non-radiative recombination...Inverted perovskite solar cells(PSCs) have attracted broad research and industrial interest owing to their suppressed hysteresis,cost-effectiveness,and easy-fabrication.However,the issue of non-radiative recombination losses at the n-type interface between the perovskite and fullerene has impeded further improvement of photovoltaic performance.Here,we modify the n-type interface of FAPbI_(3) perovskite films by constructing a stereochemical two-dimensional(2D) perovskite interlayer,in which the organic cations comprise both pyridine and ammonium groups.The pyridine N donor can create stable bonding with the surface-uncoordinated Pb on the perovskite,thereby passivating the shallow-level defects and enhancing the air stability of the film.Furthermore,the pyridine N donor also offers a positive polar interface to decrease the surface work function of the perovskite film,enabling n-type modification.Ultimately,we employ a p-i-n photovoltaic(PV) device with the positive dipole interlayer at perovskite/fullerene contact and achieve remarkable photoelectric conversion efficiency(PCE) of 22.0%.展开更多
Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At pre...Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur frequently.In this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central China.Phylogenetic and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV isolates.It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.展开更多
Catalysis of molecular radicals is often performed in interesting experimental configurations.One possible configuration is tubular geometry.The radicals are introduced into the tubes on one side,and stable molecules ...Catalysis of molecular radicals is often performed in interesting experimental configurations.One possible configuration is tubular geometry.The radicals are introduced into the tubes on one side,and stable molecules are exhausted on the other side.The penetration depth of radicals depends on numerous parameters,so it is not always feasible to calculate it.This article presents systematic measurements of the penetration depth of oxygen atoms along tubes made from nickel,cobalt,and copper.The source of O atoms was a surfatron-type microwave plasma.The initial density of O atoms depended on the gas flow and was 0.7×10^(21)m^(-3),2.4×10^(21)m^(-3),and 4.2×10^(21)m^(-3)at the flow rates of 50,300,and 600 sccm,and pressures of 10,35,and 60 Pa,respectively.The gas temperature remained at room temperature throughout the experiments.The dissociation fraction decreased exponentially along the length of the tubes in all cases.The penetration depths for well-oxidized nickel were 1.2,1.7,and 2.4 cm,respectively.For cobalt,they were slightly lower at 1.0,1.3,and 1.6 cm,respectively,while for copper,they were 1.1,1.3,and 1.7 cm,respectively.The results were explained by gas dynamics and heterogeneous surface association.These data are useful in any attempt to estimate the loss of molecular fragments along tubes,which serve as catalysts for the association of various radicals to stable molecules.展开更多
The NiO_(x)/perovskite interface in NiO_(x)-based inverted perovskite solar cells(PSCs)is one of the main issues that restrict device performance and long-term stability,as the unwanted interfacial defects and undesir...The NiO_(x)/perovskite interface in NiO_(x)-based inverted perovskite solar cells(PSCs)is one of the main issues that restrict device performance and long-term stability,as the unwanted interfacial defects and undesirable redox reactions cause severe interfacial non-radiative recombination and open-circuit voltage(Voc)loss.Herein,a series of self-assembled molecules(SAMs)are employed to bind,bridge,and stabilize the NiO_(x)/perovskite interface by regulating the electrostatic potential.Based on systematically theoretical and experimental studies,4-pyrazolecarboxylic acid(4-PCA)is proven as an efficient molecule to simultaneously passivate the NiO_(x)and perovskite surface traps,release the interfacial tensile stress as well as quench the detrimental interface redox reactions,thus effectively suppressing the interfacial non-radiative recombination and enhancing the quality of perovskite crystals.Consequently,the PSCs with 4-PCA treatment exhibited an eminently increased Voc,leading to a significant increase in power conversion efficiency from 21.28%to 23.77%.Furthermore,the unencapsulated devices maintain 92.6%and 81.3%of their initial PCEs after storing in air with a relative humidity of 20%–30%for 1000 h and heating at 65℃for 500 h in a N_(2)-filled glovebox,respectively.展开更多
Suppressing nonradiative recombination and releasing residual strain areprerequisites to improving the efficiency and stability of perovskite solar cells(PSCs).Here,long-chain polyacrylic acid(PAA)is used to reinforce...Suppressing nonradiative recombination and releasing residual strain areprerequisites to improving the efficiency and stability of perovskite solar cells(PSCs).Here,long-chain polyacrylic acid(PAA)is used to reinforce SnO_(2)film and passivate SnO_(2)defects,forming a structure similar to“reinforcedconcrete”with high tensile strength and fewer microcracks.Simultaneously,PAA is also introduced to the SnO_(2)/perovskite interface as a“buffer spring”torelease residual strain,which also acts as a“dual-side passivation interlayer”to passivate the oxygen vacancies of SnO_(2)and Pb dangling bonds in halideperovskites.As a result,the best inorganic CsPbBr_(3)PSC achieves a championpower conversion efficiency of 10.83%with an ultrahigh open-circuit voltageof 1.674 V.The unencapsulated PSC shows excellent stability under 80%relative humidity and 80℃over 120 days.展开更多
We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn un...We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications.展开更多
This study presents experimental evidence of the dependence of non-radiative recombination processes on the electron-phonon coupling of perovskite in perovskite solar cells(PSCs).Via A-site cation engineering,a weaker...This study presents experimental evidence of the dependence of non-radiative recombination processes on the electron-phonon coupling of perovskite in perovskite solar cells(PSCs).Via A-site cation engineering,a weaker electron-phonon coupling in perovskite has been achieved by introducing the structurally soft cyclohexane methylamine(CMA^(+))cation,which could serve as a damper to alleviate the mechanical stress caused by lattice oscillations,compared to the rigid phenethyl methylamine(PEA^(+))analog.It demonstrates a significantly lower non-radiative recombination rate,even though the two types of bulky cations have similar chemical passivation effects on perovskite,which might be explained by the suppressed carrier capture process and improved lattice geometry relaxation.The resulting PSCs achieve an exceptional power conversion efficiency(PCE)of 25.5%with a record-high opencircuit voltage(V_(OC))of 1.20 V for narrow bandgap perovskite(FAPbI_(3)).The established correlations between electron-phonon coupling and non-radiative decay provide design and screening criteria for more effective passivators for highly efficient PSCs approaching the Shockley-Queisser limit.展开更多
Amidst the global energy and environmental crisis,the quest for efficient solar energy utilization intensifies.Perovskite solar cells,with efficiencies over 26%and cost-effective production,are at the forefront of res...Amidst the global energy and environmental crisis,the quest for efficient solar energy utilization intensifies.Perovskite solar cells,with efficiencies over 26%and cost-effective production,are at the forefront of research.Yet,their stability remains a barrier to industrial application.This study introduces innovative strategies to enhance the stability of inverted perovskite solar cells.By bulk and surface passivation,defect density is reduced,followed by a"passivation cleaning"using Apacl amino acid salt and isopropyl alcohol to refine film surface quality.Employing X-ray diffraction(XRD),scanning electron microscope(SEM),and atomic force microscopy(AFM),we confirmed that this process effectively neutralizes surface defects and curbs non-radiative recombination,achieving 22.6%efficiency for perovskite solar cells with the composition Cs_(0.15)FA_(0.85)PbI_(3).Crucially,the stability of treated cells in long-term tests has been markedly enhanced,laying groundwork for industrial viability.展开更多
Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not ...Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not been fully investigated.This study aimed to systematically analyze the HRD status of untreated NSCLC and its relationship with patient prognosis to further guide clinical care.Methods:A total of 355 treatment-naïve NSCLC patients were retrospectively enrolled.HRD status was assessed using the AmoyDx Genomic Scar Score(GSS),with a score of≥50 considered HRD-positive.Genomic,transcriptomic,tumor microenvironmental characteristics and prognosis between HRD-positive and HRDnegative patients were analyzed.Results:Of the patients,25.1%(89/355)were HRD-positive.Compared to HRD-negative patients,HRDpositive patients had more somatic pathogenic homologous recombination repair(HRR)mutations,higher tumor mutation burden(TMB)(P<0.001),and fewer driver gene mutations(P<0.001).Furthermore,HRD-positive NSCLC had more amplifications in PI3K pathway and cell cycle genes,MET and MYC in epidermal growth factor receptor(EGFR)/anaplastic lymphoma kinase(ALK)mutant NSCLC,and more PIK3CA and AURKA in EGFR/ALK wild-type NSCLC.HRD-positive NSCLC displayed higher tumor proliferation and immunosuppression activity.HRD-negative NSCLC showed activated signatures of major histocompatibility complex(MHC)-II,interferon(IFN)-γand effector memory CD8+T cells.HRD-positive patients had a worse prognosis and shorter progressionfree survival(PFS)to targeted therapy(first-and third-generation EGFR-TKIs)(P=0.042).Additionally,HRDpositive,EGFR/ALK wild-type patients showed a numerically lower response to platinum-free immunotherapy regimens.Conclusions:Unique genomic and transcriptional characteristics were found in HRD-positive NSCLC.Poor prognosis and poor response to EGFR-TKIs and immunotherapy were observed in HRD-positive NSCLC.This study highlights potential actionable alterations in HRD-positive NSCLC,suggesting possible combinational therapeutic strategies for these patients.展开更多
基金Open access funding provided by North-West University
文摘This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operating principle for hydrogen fuel cells to establish forced circulation of the hydrogen mixture as an alternative to natural circulation(as is not utilized in conventional passive autocatalytic hydrogen recombiners currently used in nuclear power plants(NPPs)).The proposed concept of applying the physical operation principles of a PEHR based on a fuel cell simultaneously increases both productivity in terms of recombined hydrogen and the concentration threshold of flameless operation(the‘ignition’limit).Thus,it is possible to reliably ensure the hydrogen explosion safety of NPPs under all conditions,including beyond-design accidents.An experimental setup was assembled to test a laboratory sample of a membrane electrode assembly(MEA)at various hydrogen concentrations near the catalytic surfaces of the electrodes,and the corresponding current–voltage characteristics were recorded.The simplest MEA based on the Advent P1100W PBI membrane demonstrated stable performance(delivery of electrical power)over a wide range of hydrogen concentrations.
基金Funded by the China Postdoctoral Science Foundation Funded Project(2015M572276)the Natural Science Foundation of Hunan Province,China(2016JJ3184)the Hunan Major Science and Technology Projects(2011FJ1006)
文摘In order to reduce the curing temperature, shorten the curing time of phenol-formaldehyde(PF) resin adhesive, and ensure the good water-solubility, NaOH and Ba(OH)_2 were used as compound catalysts. The influences of the adding time of Ba(OH)_2, the adding amount of NaOH, Ba(OH)_2 and resorcinol on the properties of adhesives were studied. The properties of NaOH catalyzed phenol-formaldehyde(PF) adhesive, NaOH and Ba(OH)_2 compound catalyzed PF adhesive, NaOH and Ba(OH)_2 compound catalyzed phenol-resorcinol-formaldehyde(PRF) adhesive, and the prepared recombinant bamboo with three kinds of adhesives were compared. The experimental results show that NaOH and Ba(OH)_2 compound catalyst not only shortens the curing time of PF adhesive, but also guarantees the suitable water solubility of adhesive. After copolycondensation with resorcinol, the curing time of adhesive is further shortened, the water solubility is improved obviously, and the highest bonding strength is obtained. Infrared spectrum analysis shows that the reaction activity point of NaOH and Ba(OH)_2 compound catalyzed PRF adhesive will increase, so that both the curing temperature and curing enthalpy decrease.
文摘The previous pharmacokinetic methods can be only limited to drug analysis in vitro, which provide less information on the distribution and metabolismof drugs, and limit the interpretation and assessment of pharmacokinetics, the determination of metabolic principles, and evaluation of treatment effect. The objective of the study was to investigate the pharmacokinetic characteristics of gene recombination angiogenesis inhibitor Kringle 5 in vivo. The SPECT/CT and specific^(131)I-Kringle 5 marked by Iodogen method were both applied to explore the pharmacokinetic characteristics of^(131)I-Kringle 5 in vivo, and to investigate the dynamic distributions of^(131)I-Kringle 5 in target organs. Labeling recombinant angiogenesis inhibitor Kringle 5 using131 I with longer half-life and imaging in vivo using SPECT instead of PET,could overcome the limitations of previous methods. When the doses of^(131)I-Kringle 5 were 10.0, 7.5 and5.0 g/kg, respectively, the two-compartment open models can be determined within all the metabolic process in vivo. There were no significant differences in t1/2α, t1/2β, apparent volume of distribution and CL between those three levels. The ratio of AUC(0 1)among three different groups of 10.0, 7.5 and 5.0 g/kg was 2.56:1.44:1.0, which was close to the ratio(2:1.5:1.0). It could be clear that in the range of 5.0–10.0 g/kg, Kringle 5 was characterized by the first-order pharmacokinetics. Approximately 30 min after^(131)I-Kringle 5 was injected,^(131)I-Kringle 5 could be observed to concentrate in the heart, kidneys, liver and other organs by means of planar imaging and tomography. After 1 h of being injected, more radionuclide retained in the bladder, but not in intestinal. It could be concluded that^(131)I-Kringle 5 is mainly excreted through the kidneys. About 2 h after the injection of^(131)I-Kringle 5, the radionuclide in the heart, kidneys,liver and other organs was gradually reduced, while more radionuclide was concentrated in the bladder.The radionuclide was completely metabolized within 24 h, and the distribution of radioactivity in rats was similar to normal levels. In our study, the specific marker^(131)I-Kringle 5 and SPECT/CT were successfully used to explore pharmacokinetic characteristics of Kringle 5 in rats. The study could provide a new evaluation platform of the specific, in vivo and real-time functional imaging and pharmacokinetics for the clinical application of^(131)I-Kringle 5.
基金the National Science Foundation Grant MCB-2212951(to CEB)and NHMRC Ideas grant APP1184012/GNT1184012(to GT).
文摘Recombineering is an essential tool for molecular biologists,allowing for the facile and efficient manipulation of bacterial genomes directly in cells without the need for costly and laborious in vitro manipulations involving restriction enzymes.The main workhorses behind recombineering are bacteriophage proteins that promote the single-strand annealing(SSA)homologous recombination pathway to repair double-stranded DNA breaks.While there have been several reviews examining recombineering methods and applications,comparatively few have focused on the mechanisms of the proteins that are the key players in the SSA pathway:a 5′→3′exonuclease and a single-strand annealing protein(SSAP or“annealase”).This review dives into the structures and functions of the two SSA recombination systems that were the first to be developed for recombineering in E.coli:the RecET system from E.coli Rac prophage and the𝜆Red system from bacteriophageλ.By comparing the structures of the RecT and Red𝛽annealases,and the RecE and𝜆Exo exonucleases,we provide new insights into how the structures of these proteins dictate their function.Examining the sequence conservation of the𝜆λExo and RecE exonucleases gives more profound insights into their critical functional features.Ultimately,as recombineering accelerates and evolves in the laboratory,a better understanding of the mechanisms of the proteins behind this powerful technique will drive the development of improved and expanded capabilities in the future.
基金the DFG grant EH 192/5-3(to AE),the internal grant program(project IFF 2024-91)f the Faculty of Health at Witten/Herdecke University(WZ and KS)and the PhD program at Witten/Herdecke University(LK).
文摘Adenoviruses typically cause mild illnesses,but severe diseases may occur primarily in immunodeficient individuals,particularly children.Recently,adenoviruses have garnered significant interest as a versatile tool in gene therapy,tumor treatment,and vaccine vector development.Over the past two decades,the advent of recombineering,a method based on homologous recombination,has notably enhanced the utility of adenoviral vectors in therapeutic applications.This review summarizes recent advancements in the use of human adenoviral vectors in medicine and discusses the pivotal role of recombineering in the development of these vectors.Additionally,it highlights the current achievements and potential future impact of therapeutic adenoviral vectors.
基金supported by the National Key R&D Program of China(2019YFA0904000)the National Natural Science Foundation of China(31570094,81502962,32170038,32270088)+1 种基金the Taishan Scholar Pro-gram of Shandong Province,the Shandong Provincial Natural Science Foundation of China(ZR2020MC015,ZR2022MC142)the Funda-mental Research Funds of Shandong University(2018GN021).
文摘Recombineering is a valuable technique for generating recombinant DNA in vivo,primarily in bacterial cells,and is based on homologous recombination using phage-encoded homologous recombinases,such as Red βγ from the lambda phage and RecET from the Rac prophage.The recombineering technique can efficiently mediate homol-ogous recombination using short homologous arms(∼50 bp)and is unlimited by the size of the DNA molecules or positions of restriction sites.In this review,we summarize characteristics of recombinases,mechanism of recombineering,and advances in recombineering for DNA manipulation in Escherichia coli and other bacteria.Furthermore,the broad applications of recombineering for mining new bioactive microbial natural products,and for viral mutagenesis,phage genome engineering,and understanding bacterial metabolism are also reviewed.
基金supported by the National Key R&D Program of China(2019YFA0905700)National Natural Science Foundation of China(32070060).
文摘Iron is essential for bacterial survival,and most bacteria capture iron by producing siderophores.Burkholde-riales bacteria produce various types of bioactive secondary metabolites,such as ornibactin and malleobactin siderophores.In this study,the genome analysis of Burkholderiales genomes showed a putative novel siderophore gene cluster crb,which is highly similar to the ornibactin and malleobactin gene clusters but does not have pvdF,a gene encoding a formyltransferase for N-δ-hydroxy-ornithine formylation.Establishing the bacteriophage recom-binase Redγ-Redδβ7029 mediated genome editing system in a non-model Burkholderiales strain Paraburkholderia caribensis CICC 10960 allowed the rapid identification of the products of crb gene cluster,caribactins A-F(1-6).Caribactins contain a special amino acid residue N-δ-hydroxy-N-δ-acetylornithine(haOrn),which differs from the counterpart N-δ-hydroxy-N-δ-formylornithine(hOrn)in ornibactin and malleobactin,owing to the absence of pvdF.Gene inactivation showed that the acetylation of hOrn is catalyzed by CrbK,whose homologs proba-bly not be involved in the biosynthesis of ornibactin and malleobactin,showing possible evolutionary clues of these siderophore biosynthetic pathways from different genera.Caribactins promote biofilm production and en-hance swarming and swimming abilities,suggesting that they may play crucial roles in biofilm formation.This study also revealed that recombineering has the capability to mine novel secondary metabolites from non-model Burkholderiales species.
基金supported by the National Key R&D Program of China(2019YFA0904000)the National Natural Science Foundation of China(31570094,81502962,32270088)+6 种基金the 111 Project(B16030)the Shan-dong Provincial Natural Science Foundation of China(ZR2020MC015,ZR2018ZC2261)the Taishan Scholar Program of Shandong Provincethe Fundamental Research Funds of Shandong University(2018GN021)the Open Project Program of the State Key Laboratory of Bio-based Material and Green Papermaking(KF201825)the Science and Technology Project of Hunan Province(2021NK1040)Natural Science Foundation of Changsha(KQ2208130).
文摘Bacillus subtilis plays an important role in fundamental and applied research,and it has been widely used as a cell factory for the production of enzymes,antimicrobial materials,and chemicals for agriculture,medicine,and industry.However,genetic manipulation tools for B.subtilis have low efficiency.In this work,our goal was to develop a simple recombineering system for B.subtilis.We showed that genome editing can be achieved in B.subtiliis 1A751 through co-expression of YqaJ/YqaK,a native phage recombinase pair found in B.sub-tilis 168,and the competence master regulator ComK using a double-stranded DNA substrate with short ho-mology arms(100 bp)and a phosphorothioate modification at the 5′-end.Efficient gene knockouts and large DNA insertions were achieved using this new recombineering system in B.subtilis 1A751.As far as we know,this is the first recombineering system using the native phage recombinase pair YqaJ/YqaK in B.subtilis.In conclusion,this new recombineering system provides a simple and fast tool for genetic manipulation of B.sub-tilis,and it will promote studies of genome function,construction of production strains,and genome mining in B.subtilis.
文摘Hydrogen challenge mitigation stands as one of the main objectives in the management of severe accidents at Nuclear Power Plants (NPPs). Key strategies for hydrogen control include atmospheric inertization and hydrogen removal with Passive Autocatalytic Recombiners (PARs) being a commonly accepted approach. However, an examination of PAR operation specificity reveals potential inefficiencies and reliability issues in certain severe accident scenarios. Moreover, during the in-vessel stage of severe accident development, in some severe accident scenarios PARs can unexpectedly become a source of hydrogen detonation. The effectiveness of hydrogen removal systems depends on various factors, including the chosen strategies, severe accident scenarios, reactor building design, and other influencing factors. Consequently, a comprehensive hydrogen mitigation strategy must effectively incorporate a combination of strategies rather than be based on one strategy, taking into consideration the probabilistic risks and uncertainties associated with the implementation of PARs or other traditional methods. In response to these considerations, within the framework of this research it has been suggested a conceptual strategy to mitigate the hydrogen challenge during the in-vessel stage of severe accident development.
基金supported by the National Key R&D Program of China(2018YFA0902200)Natural Science Foundation of China(No.21776157,No.22078173)。
文摘Genome engineering of Rhodococcus opacus PD630,an important microorganism used for the bioconversion of lignin,is currently dependent on inefficient homologous recombination.Although a CRISPR interference procedure for gene repression has previously been developed for R.opacus PD630,a CRISPR/Cas9 system for gene knockout has yet to be reported for the strain.In this study,we found that the cytotoxicity of Cas9 and the deficiency in pathways for repairing DNA double-strand breaks(DSBs)were the major causes of the failure of conventional CRISPR/Cas9 technologies in R.opacus,even when augmented with the recombinases Che9c60 and Che9c61.We successfully developed an efficient single-stranded DNA(ssDNA)recombineering system coupled with CRISPR/Cas9 counter-selection,which facilitated rapid and scarless editing of the R.opacus genome.A two-plasmid system,comprising Cas9 driven by a weak Rhodococcus promoter Pniami,designed to prevent cytotoxicity,and a single-guide RNA(sgRNA)under the control of a strong constitutive promoter,was proven to be appropriate with respect to cleavage function.A novel recombinase,RrRecT derived from a Rhodococcus ruber prophage,was identified for the first time,which facilitated recombination of short ssDNA donors(40-80 nt)targeted to the lagging strand and enabled us to obtain a recombination efficiency up to 103-fold higher than that of endogenous pathways.Finally,by incorporating RrRecT and Cas9 into a single plasmid and then co-transforming cells with sgRNA plasmids and short ssDNA donors,we efficiently achieved gene disruption and base mutation in R.opacus,with editing efficiencies ranging from 22%to 100%.Simultaneous disruption of double genes was also confirmed,although at a lower efficiency.This effective genome editing tool will accelerate the engineering of R.opacus metabolism.
基金This work was supported by the National Natural Science Foundation of China(62104136,22179051)the National Key Research and Development Program of China(2021YFE0111000)+3 种基金Project of Shandong Province Higher Educational Young Innovative Team(2022KJ218)China Postdoctoral Science Foundation(2023M732104)Qingdao Postdoctoral Funding Program(QDBSH20220201002)Postdoctoral Innovation Project of Shandong Province(SDCX-ZG-202303032).
文摘The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and stability.However,a comprehensive manipulation of the buried interface in terms of the transport layer,buried interlayer,and perovskite layer has been largely overlooked.Herein,we propose the use of a volatile heterocyclic compound called 2-thiopheneacetic acid(TPA)as a pre-buried additive in the buried interface to achieve cross-layer all-interface defect passivation through an in situ bottom-up infiltration diffusion strategy.TPA not only suppresses the serious interfacial nonradiative recombination losses by precisely healing the interfacial and underlying defects but also effectively enhances the quality of perovskite film and releases the residual strain of perovskite film.Owing to this versatility,TPA-tailored CsPbBr3 PSCs deliver a record efficiency of 11.23% with enhanced long-term stability.This breakthrough in manipulating the buried interface using TPA opens new avenues for further improving the performance and reliability of PSC.
基金financially supported by the National Ten Thousand Talent Program for Young Top-notch Talent,China,the National Natural Science Fund for Excellent Young Scholars,China(52022030)the National Natural Science Foundation of China,China(51972111,52203330)+7 种基金the Shanghai Pilot Program for Basic Research,China(22TQ1400100-5)the “Dawn”Program of Shanghai Education Commission,China(22SG28)the Shanghai Municipal Natural Science Foundation,China(22ZR1418000)the Science and Technology Innovation Plan of Shanghai Science and Technology Commission,China(22YF1410000)the Postdoctoral Research Foundation of China,China(2021M701190)the Fundamental Research Funds for the Central Universities,China(JKD01231632,JKVD1231041)the Major Science and Technology Projects of Inner Mongolia Autonomous Region,China(2021ZD0042)the Shanghai Engineering Research Center of Hierarchical Nanomaterials,China(18DZ2252400)。
文摘Inverted perovskite solar cells(PSCs) have attracted broad research and industrial interest owing to their suppressed hysteresis,cost-effectiveness,and easy-fabrication.However,the issue of non-radiative recombination losses at the n-type interface between the perovskite and fullerene has impeded further improvement of photovoltaic performance.Here,we modify the n-type interface of FAPbI_(3) perovskite films by constructing a stereochemical two-dimensional(2D) perovskite interlayer,in which the organic cations comprise both pyridine and ammonium groups.The pyridine N donor can create stable bonding with the surface-uncoordinated Pb on the perovskite,thereby passivating the shallow-level defects and enhancing the air stability of the film.Furthermore,the pyridine N donor also offers a positive polar interface to decrease the surface work function of the perovskite film,enabling n-type modification.Ultimately,we employ a p-i-n photovoltaic(PV) device with the positive dipole interlayer at perovskite/fullerene contact and achieve remarkable photoelectric conversion efficiency(PCE) of 22.0%.
基金supported by the National Natural Science Foundation of China(32202788)the Special Research Fund of Shanxi Agricultural University for High-level Talents,China(2021XG004)+3 种基金the Fund for Shanxi“1331 Project”,China(20211331-13)the Shanxi Province Excellent Doctoral Work Award-Scientific Research Project,China(SXBYKY2021063,SXBYKY2021005,and SXBYKY 2022014)the earmarked fund for Modern Agro-industry Technology Research System of Shanxi Province,China(2023CYJSTX15-13)the Fundamental Research Program of Shanxi Province,China(202103021224156)。
文摘Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur frequently.In this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central China.Phylogenetic and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV isolates.It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.
基金funded by the Slovenian Research Agency,Core Funding(No.P2-0082)and Project(No.L24487)。
文摘Catalysis of molecular radicals is often performed in interesting experimental configurations.One possible configuration is tubular geometry.The radicals are introduced into the tubes on one side,and stable molecules are exhausted on the other side.The penetration depth of radicals depends on numerous parameters,so it is not always feasible to calculate it.This article presents systematic measurements of the penetration depth of oxygen atoms along tubes made from nickel,cobalt,and copper.The source of O atoms was a surfatron-type microwave plasma.The initial density of O atoms depended on the gas flow and was 0.7×10^(21)m^(-3),2.4×10^(21)m^(-3),and 4.2×10^(21)m^(-3)at the flow rates of 50,300,and 600 sccm,and pressures of 10,35,and 60 Pa,respectively.The gas temperature remained at room temperature throughout the experiments.The dissociation fraction decreased exponentially along the length of the tubes in all cases.The penetration depths for well-oxidized nickel were 1.2,1.7,and 2.4 cm,respectively.For cobalt,they were slightly lower at 1.0,1.3,and 1.6 cm,respectively,while for copper,they were 1.1,1.3,and 1.7 cm,respectively.The results were explained by gas dynamics and heterogeneous surface association.These data are useful in any attempt to estimate the loss of molecular fragments along tubes,which serve as catalysts for the association of various radicals to stable molecules.
基金financially supported by the National Natural Science Foundation of China (U22A2078)Fundamental Research Funds for the Central Universities (2022CDJQY-007)
文摘The NiO_(x)/perovskite interface in NiO_(x)-based inverted perovskite solar cells(PSCs)is one of the main issues that restrict device performance and long-term stability,as the unwanted interfacial defects and undesirable redox reactions cause severe interfacial non-radiative recombination and open-circuit voltage(Voc)loss.Herein,a series of self-assembled molecules(SAMs)are employed to bind,bridge,and stabilize the NiO_(x)/perovskite interface by regulating the electrostatic potential.Based on systematically theoretical and experimental studies,4-pyrazolecarboxylic acid(4-PCA)is proven as an efficient molecule to simultaneously passivate the NiO_(x)and perovskite surface traps,release the interfacial tensile stress as well as quench the detrimental interface redox reactions,thus effectively suppressing the interfacial non-radiative recombination and enhancing the quality of perovskite crystals.Consequently,the PSCs with 4-PCA treatment exhibited an eminently increased Voc,leading to a significant increase in power conversion efficiency from 21.28%to 23.77%.Furthermore,the unencapsulated devices maintain 92.6%and 81.3%of their initial PCEs after storing in air with a relative humidity of 20%–30%for 1000 h and heating at 65℃for 500 h in a N_(2)-filled glovebox,respectively.
基金Qingdao Postdoctoral Funding Program,Grant/Award Number:QDBSH20220201002National Key Research and Development Program of China,Grant/Award Number:2021YFE0111000+1 种基金Project of Shandong Province Higher Educational Young Innovative Team,Grant/Award Number:2022KJ218National Natural Science Foundation of China,Grant/Award Numbers:62104136,22179051,22109053。
文摘Suppressing nonradiative recombination and releasing residual strain areprerequisites to improving the efficiency and stability of perovskite solar cells(PSCs).Here,long-chain polyacrylic acid(PAA)is used to reinforce SnO_(2)film and passivate SnO_(2)defects,forming a structure similar to“reinforcedconcrete”with high tensile strength and fewer microcracks.Simultaneously,PAA is also introduced to the SnO_(2)/perovskite interface as a“buffer spring”torelease residual strain,which also acts as a“dual-side passivation interlayer”to passivate the oxygen vacancies of SnO_(2)and Pb dangling bonds in halideperovskites.As a result,the best inorganic CsPbBr_(3)PSC achieves a championpower conversion efficiency of 10.83%with an ultrahigh open-circuit voltageof 1.674 V.The unencapsulated PSC shows excellent stability under 80%relative humidity and 80℃over 120 days.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12004067,11974070,62027807,and 52272137)the National Key R&D Program of China(Grant No.2022YFA1403000)。
文摘We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications.
基金supported by the National Natural Science Foundation of China(U21A20331,81903743,22005322,22279151,and 22275004)National Science Fund for Distinguished Young Scholars(21925506).
文摘This study presents experimental evidence of the dependence of non-radiative recombination processes on the electron-phonon coupling of perovskite in perovskite solar cells(PSCs).Via A-site cation engineering,a weaker electron-phonon coupling in perovskite has been achieved by introducing the structurally soft cyclohexane methylamine(CMA^(+))cation,which could serve as a damper to alleviate the mechanical stress caused by lattice oscillations,compared to the rigid phenethyl methylamine(PEA^(+))analog.It demonstrates a significantly lower non-radiative recombination rate,even though the two types of bulky cations have similar chemical passivation effects on perovskite,which might be explained by the suppressed carrier capture process and improved lattice geometry relaxation.The resulting PSCs achieve an exceptional power conversion efficiency(PCE)of 25.5%with a record-high opencircuit voltage(V_(OC))of 1.20 V for narrow bandgap perovskite(FAPbI_(3)).The established correlations between electron-phonon coupling and non-radiative decay provide design and screening criteria for more effective passivators for highly efficient PSCs approaching the Shockley-Queisser limit.
基金supported by the National Natural Science Foundation of China(61874008).
文摘Amidst the global energy and environmental crisis,the quest for efficient solar energy utilization intensifies.Perovskite solar cells,with efficiencies over 26%and cost-effective production,are at the forefront of research.Yet,their stability remains a barrier to industrial application.This study introduces innovative strategies to enhance the stability of inverted perovskite solar cells.By bulk and surface passivation,defect density is reduced,followed by a"passivation cleaning"using Apacl amino acid salt and isopropyl alcohol to refine film surface quality.Employing X-ray diffraction(XRD),scanning electron microscope(SEM),and atomic force microscopy(AFM),we confirmed that this process effectively neutralizes surface defects and curbs non-radiative recombination,achieving 22.6%efficiency for perovskite solar cells with the composition Cs_(0.15)FA_(0.85)PbI_(3).Crucially,the stability of treated cells in long-term tests has been markedly enhanced,laying groundwork for industrial viability.
基金supported by the National High Level Hospital Clinical Research Funding(No.BJ-2219-195 and No.BJ-2023-090).
文摘Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not been fully investigated.This study aimed to systematically analyze the HRD status of untreated NSCLC and its relationship with patient prognosis to further guide clinical care.Methods:A total of 355 treatment-naïve NSCLC patients were retrospectively enrolled.HRD status was assessed using the AmoyDx Genomic Scar Score(GSS),with a score of≥50 considered HRD-positive.Genomic,transcriptomic,tumor microenvironmental characteristics and prognosis between HRD-positive and HRDnegative patients were analyzed.Results:Of the patients,25.1%(89/355)were HRD-positive.Compared to HRD-negative patients,HRDpositive patients had more somatic pathogenic homologous recombination repair(HRR)mutations,higher tumor mutation burden(TMB)(P<0.001),and fewer driver gene mutations(P<0.001).Furthermore,HRD-positive NSCLC had more amplifications in PI3K pathway and cell cycle genes,MET and MYC in epidermal growth factor receptor(EGFR)/anaplastic lymphoma kinase(ALK)mutant NSCLC,and more PIK3CA and AURKA in EGFR/ALK wild-type NSCLC.HRD-positive NSCLC displayed higher tumor proliferation and immunosuppression activity.HRD-negative NSCLC showed activated signatures of major histocompatibility complex(MHC)-II,interferon(IFN)-γand effector memory CD8+T cells.HRD-positive patients had a worse prognosis and shorter progressionfree survival(PFS)to targeted therapy(first-and third-generation EGFR-TKIs)(P=0.042).Additionally,HRDpositive,EGFR/ALK wild-type patients showed a numerically lower response to platinum-free immunotherapy regimens.Conclusions:Unique genomic and transcriptional characteristics were found in HRD-positive NSCLC.Poor prognosis and poor response to EGFR-TKIs and immunotherapy were observed in HRD-positive NSCLC.This study highlights potential actionable alterations in HRD-positive NSCLC,suggesting possible combinational therapeutic strategies for these patients.