Objective:To systematically evaluate the efficacy and safety of Duhuo Jisheng decoction combined with manipulation in the treatment of lumbar disc herniation.Method:We systematically searched 8 databases at home and a...Objective:To systematically evaluate the efficacy and safety of Duhuo Jisheng decoction combined with manipulation in the treatment of lumbar disc herniation.Method:We systematically searched 8 databases at home and abroad.Literature quality of the included studies was evaluated by the bias risk assessment tool of Cochrane collaboration network,and the Meta-analysis was performed by RevMan 5.3 software.Result:A total of 427 related literature were retrieved,and 12 studies were eventually included,involving 1153 patients.All studies were in Chinese.Meta-analysis results showed that the total effective rate of Duhuo Jisheng decoction combined with manipulation in the treatment of LDH was better than that of the control group(RR=1.23,95%CI[1.17,1.29],P<0.00001).Subgroup analysis showed that Duhuo Jisheng decoction combined with manipulation had a more significant effect than conventional treatment(RR=1.34,95%CI[1.20,1.50],P<0.00001),nonsteroidal anti-inflammatory drugs(RR=1.24,95%CI[1.12,1.37],P<0.0001),and Yaotongning capsules(RR=1.19,95%CI[1.10,1.29],P<0.0001).It has obvious advantages in improving VAS scores(MD=-1.19,95%CI-1.19[-1.87,-0.51],P=0.0006),but it has no obvious advantages in improving JOA scores(MD=2.6595%CI[0.06,5.24],P=0.05).In terms of safety,Duhuo Jisheng decoction combined with manipulation treatment reported fewer adverse events.Conclusion:The Duhuo Jisheng decoction combined with manipulation treatment can effectively relieve the clinical symptoms of patients with lumbar disc herniation,with obvious clinical efficacy,and fewer adverse events.But in view of the limitations of clinical studies,there are some limitations in this study,and more studies with high quality of evidence are needed to further confirm its efficacy and safety.展开更多
Theβsolidifiedγ-TiAl alloy holds important application value in the aerospace industry,while its com-plex phase compositions and geometric structures pose challenges to its microstructure control during the thermal-...Theβsolidifiedγ-TiAl alloy holds important application value in the aerospace industry,while its com-plex phase compositions and geometric structures pose challenges to its microstructure control during the thermal-mechanical process.The microstructure evolution of Ti-43Al-4Nb-1Mo-0.2B alloy at 1200℃/0.01 s−1 was investigated to clarify the coupling role of dynamic recrystallization(DRX)and phase transformation.The results revealed that the rate of DRX inα2+γlamellar colonies was comparatively slower than that inβo+γmixed structure,instead being accompanied by intense lamellar kinking and rotation.The initiation and development rates of DRX inα2,βo,andγphases decreased sequentially.The asynchronous DRX of the various geometric structures and phase compositions resulted in the un-even deformed microstructure,and the dynamic softening induced by lamellar kinking and rotation was replaced by strengthened DRX as strain increased.Additionally,the blockyα2 phase and the terminals ofα2 lamellae were the preferential DRX sites owing to the abundant activated slip systems.Theα2→βo transformation within lamellar colonies facilitated DRX and fragment ofα2 lamellae,while theα2→γtransformation promoted the decomposition ofα2 lamellae and DRX ofγlamellae.Moreover,the var-iedβo+γmixed structures underwent complicated evolution:(1)Theγ→βo transformation occurred at boundaries of lamellar colonies,followed by simultaneous DRX ofγlamellar terminals and neighboringβo phase;(2)DRX occurred earlier within the band-likeβo phase,with the delayed DRX in enclosedγphase;(3)DRX within theβo synapses and neighboringγphase was accelerated owing to generation of elastic stress field;(4)Dispersedβo particles triggered particle stimulated nucleation(PSN)ofγphase.Eventually,atomic diffusion along crystal defects inβo andγphases caused fracture of band-likeβo phase and formation of massiveβo particles,impeding grain boundary migration and hindering DRXed grain growth ofγphase.展开更多
Background:The prognostic significance of the chemokine receptor CCR7 in diffuse large B-cell lymphoma(DLBCL)has been reported previously.However,the detailed mechanisms of CCR7 in DLBCL,particularly regarding its int...Background:The prognostic significance of the chemokine receptor CCR7 in diffuse large B-cell lymphoma(DLBCL)has been reported previously.However,the detailed mechanisms of CCR7 in DLBCL,particularly regarding its interaction with lenalidomide treatment,are not fully understood.Methods:Our study utilized bioinformatics approaches to identify hub genes in SU-DHL-2 cell lines treated with lenalidomide compared to control groups.Immunohistochemical data and clinical information from 122 patients with DLBCL were analyzed to assess the correlation of CCR7 and p-ERK1/2 expression with the prognosis of DLBCL.Furthermore,in vitro and in vivo experiments were conducted to clarify the role of CCR7 in the response of DLBCL to lenalidomide treatment.Results:Our bioinformatics analysis pinpointed CCR7 as a hub gene in the context of lenalidomide treatment in DLBCL.Notably,31.14%and 36.0%(44/122)of DLBCL cases showed positive expression for CCR7 and ERK1/2 respectively,establishing them as independent prognostic factors for adverse outcomes in DLBCL via multivariate Cox regression analysis.Additionally,our studies demonstrated that the external application of the protein CCL21 promoted proliferation,migration,invasion,and activation of the ERK1/2 pathway in SU-DHL-2 and OCI-LY3 cell lines with high levels of CCR7 expression.This effect was mitigated by CCR7 silencing through siRNA,application of ERK inhibitors,or lenalidomide treatment.In vivo experiments reinforced the efficacy of lenalidomide,significantly reducing tumor growth rate,tumor mass,serum total LDH levels,and expression of CCR7 and p-ERK1/2 in a SUDHL-2 xenograft model in nude mice(p<0.05).Conclusion:Our study clarifies the potential role of the CCL21/CCR7/ERK1/2 axis in the therapeutic effects of lenalidomide in DLBCL treatment.展开更多
Liver metastasis （LM） is one of the major causes of death in patients with colorectal cancer （CRC）. Approxi-mately 60% of CRC patients develop LM during the course of their illness. About 85% of these patients hav...Liver metastasis （LM） is one of the major causes of death in patients with colorectal cancer （CRC）. Approxi-mately 60% of CRC patients develop LM during the course of their illness. About 85% of these patients have unresectable disease at the time of presenta-tion. Surgical resection is currently the only curative treatment for patients with colorectal LM （CRLM）. In recent years, with the help of modern multimodality therapy including systemic chemotherapy, radiation therapy, and surgery, the outcomes of CRLM treatment have signifcantly improved. This article summarizes the current status of surgical treatment of CRLM including evaluation of resectability, treatment for resectable LM, conversion therapy and liver transplantation for unresectable cases, liver resection for recurrent CRLM and elderly patients, and surgery for concomitanthepatic and extra-hepatic metastatic disease （EHMD）. We believe that with the help of modern multimodality therapy, an aggressive oncosurgical approach should be implemented as it has the possibility of achieving a cure, even when EHMD is present in patients with CRLM.展开更多
The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the prima...The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the primary line of defense in maintaining physiological equilibrium,the epidermis of the porpoise is expected to have undergone structural adaptations due to the shift from the marine to the freshwater environment.This study compared the microstructural and ultrastructural features of the epidermis of YFP and its marine counterpart,the East Asian finless porpoise(Neophocaena asiaeorientalis sunameri,Pilleri&Gihr,1975;EAFP).Microscopic structural observations and statistical analyses of the epidermal thickness demonstrated no significant differences in the cell structure or distribution between the two porpoise species.However,the epidermis of the YFP contained more abundant stratum basale cells.The outermost lipid stratum corneum exhibited a thinner cell layer with wider neutral lipid droplets to resist the passive entry of water molecules in the hypotonic environment.In contrast,for the EAFp,a more uniformly arranged stratum basale in the epidermis led to denser keratin fibers and robust desmosomes within each epidermal layer at the ultrastructural level.This tight arrangement of cells can reduce transepidermal water loss(TEWL)in an environment with higher osmotic pressure.In conclusion,the 2 finless porpoise species appear to employ different epidermal mechanisms to adapt to their distinct osmotic environments.The YFP appears to possess a"lipid waterproofing"epidermal structure,while the EAFP possesses a"thick and compact water-retaining"epidermal structure to copewithpotentialwaterloss.展开更多
The integration of boronizing and austempering termed boro-austempering treatment is a new processing route for preparing high strength bainitic steel with high surface hardness and high corrosion resistance.The micro...The integration of boronizing and austempering termed boro-austempering treatment is a new processing route for preparing high strength bainitic steel with high surface hardness and high corrosion resistance.The microstructure and properties of a medium-carbon bainitic steel prepared by boro-austempering treatment were characterized and analyzed.The results show that a single Fe_(2)B layer on bainite substrate was obtained with surface hardness of~1400 HV,and the critical load for adhesive failure of borided layer reached 73.6 N.The silicon-rich α-Fe phase in transition zone was clarified as ferrite,which was formed at the beginning stage of cooling process from boronizing to low-temperature bainite transformation.Moreover,the relative potential differences between Fe_(2)B and bainite matrix,and ferrite and bainite matrix were 75 and 92 mV,respectively,with bainite matrix acting as active anode,indicating that the corrosion resistances of Fe2B and ferrite were better than that of bainite.展开更多
Anaerobic ammonia oxidation(Anammox)is an economical and sustainablewastewater nitrogen removal technology,and its application in the mainstream process is the inevitable trend of the development of Anammox.However,ho...Anaerobic ammonia oxidation(Anammox)is an economical and sustainablewastewater nitrogen removal technology,and its application in the mainstream process is the inevitable trend of the development of Anammox.However,how to effectively enriching Anammox bacteria from the activated sludge remains challenging and restricts its extensive applications.In this study,the rapid and efficient enrichment of Anammox bacteriawas achieved by raising the reflux ratio and nitrogen loading rate(NLR)using conventional activated sludge as the inoculant.In the screening phase(days 1–90),the reflux ratio was increased to discharge partial floc sludge,resulting in the relative abundance of Candidatus Brocadiaceae increased from0.04%to 22.54%,which effectively reduced thematrix and spatial competition between other microorganisms and Anammox bacteria.On day 90,the stoichiometric ratio of the Anammox process closely approached the theoretical value of 1:1.32:0.26,indicating that the Anammox reaction was the primary nitrogen removal process in the system.In the enrichment phase(days 91–238),the NLR increased from 0.43 to 1.20 kgN/(m^(3)·d)and removal efficiency was 71.89%,resulting in the relative abundance of Candidatus Brocadiaceae increased to 61.27%on day 180.The reactor operated steadily from days 444 to 498,maintaining the nitrogen removal rate(NRR)of 3.00 kgN/(m^(3)·d)and achieving successful sludge granulation with the particle size of 392.4μm.In short,this study provided a simple and efficient approach for enriching Anammox bacteria from the activated sludge,supporting to start an Anammox process efficiently.展开更多
Lithium-sulfur batteries(LSBs)have attracted significant attention due to their high theoretical energy density and low-cost raw materials.However,LSBs still face various challenges in practical applications,particula...Lithium-sulfur batteries(LSBs)have attracted significant attention due to their high theoretical energy density and low-cost raw materials.However,LSBs still face various challenges in practical applications,particularly the shuttle effect,electrode passivation,and slow kinetics.In recent years,trisulfur radicals(TRs),important intermediates in LSBs,have emerged as a promising and beyond-traditional solution to these problems,which serves as a mediated catalyst to improve the electrochemical performance of LSBs.As a system that is inconsistent with the catalytic conversion process discussed in the traditional LSBs,this review focuses on the generation,detection,promotion,and catalytic roles of TRs,especially emphasizing the formation of TRs in solid-state lapis lazuli analogs and discussing the pros and cons of high donor number solvents and/or their co-solvents in stabilizing TRs.Strategies involving homogeneous/heterogeneous catalysts are discussed for increment of TRs and enhancing catalytic reactions in LSBs.Ultimately,given TRs’significant potential as a key factor in enhancing the performance of LSBs,future perspectives and outlooks are provided to guide the further development of TRs in LSBs.This review provides valuable insights into the design of electrolytes and catalysts for increment of TRs,paving the new practical direction and way for advanced LSBs.展开更多
BACKGROUND Despite advances in the use of in vitro fertilization-embryo transfer(ET)in couples with infertility,recurrent implantation failure(RIF)after ET is still a major problem affecting women,with great psycholog...BACKGROUND Despite advances in the use of in vitro fertilization-embryo transfer(ET)in couples with infertility,recurrent implantation failure(RIF)after ET is still a major problem affecting women,with great psychological and economic burdens for the patient and his/her family.AIM To investigate the psychological burden(anxiety and depression)and evaluate the clinical benefits of endometrial receptivity testing(ERT)in patients experiencing RIF following frozen-thawed ET.METHODS A retrospective cohort study analyzed 371 patients experiencing RIF after assisted reproductive treatment at the First People’s Hospital of Changde City between January 2021 and June 2024.Demographic and clinical data were systematically collected through standardized questionnaires.Psychological assessment utilized validated instruments:The Self-Rating Depression Scale for depression evaluation and the Self-Rating Anxiety Scale for anxiety assessment.Participants were stratified by psychological status(anxiety/non-anxiety and depression/nondepression)to analyze influencing factors for anxiety and depression.The cohort was further categorized into the ERT and non-ERT groups based on ERT implementation to comparatively analyze their clinical outcomes.Additionally,they were divided into clinical and nonclinical pregnancy groups to identify factors affecting clinical pregnancy using univariate and multivariate logistic regression models.Compared with the non-ERT group,the 226 patients who underwent ERT-guided ET achieved a higher clinical pregnancy rate,thicker endometrium on transfer day,fewer embryos transferred,and a lower miscarriage rate.RESULTS The study identified a substantial psychological burden,with anxiety prevalence at 55.0%(mean Self-Rating Anxiety Scale score,50.89±9.34)and depression at 61.2%(mean Self-Rating Depression Scale score,55.55±9.48).Multivariate analysis identified annual household income>100000 yuan as protective factors against both anxiety and depression,whereas advanced maternal age(>35 years)and multiple implantation failures(≥3)served as risk factors.Additionally,anxiety-specific risk factors included prolonged infertility treatment(>5 years)and the spouse’s status as an only child.As to depression-specific risks,chronic infertility(>3 years)and higher educational attainment(college/bachelor’s degree or higher)were key determinants,whereas urban residence was a protective factor.Age>35 years was a risk factor for clinical pregnancy in patients experiencing RIF,whereas blastocyst-stage ET,a higher number of embryos transferred,and thicker endometrium were protective factors.CONCLUSION Patients experiencing RIF are particularly susceptible to anxiety and depression,and advanced maternal age and multiple implantation failures represent salient risk factors.Clinicians should implement proactive and evidencebased interventions to mitigate these psychological burdens.For patients experiencing RIF,ERT-guided ET demonstrates significant potential to improve assisted reproductive outcomes.展开更多
Toxoplasma gondii(T.gondii)is a globally distributed parasite that can infect a diversity of warm-blooded animals,including swine and humans.Infection in swine poses a considerable threat to food safety and public hea...Toxoplasma gondii(T.gondii)is a globally distributed parasite that can infect a diversity of warm-blooded animals,including swine and humans.Infection in swine poses a considerable threat to food safety and public health.The aim of this meta-analysis was to estimate the seroprevalence of T.gondii infection in the swine population in China from 2000 to 2023 and to examine potential factors associated with infection.A total of 112 studies were included,collectively involving 145,152 swine samples originating from 26 provinces.The pooled seroprevalence was 26.0%(95%CI:23.3%–28.7%).Stratified analysis based on diagnostic methods revealed that studies using the indirect hemagglutination assay(IHA)reported a seroprevalence of 19.7%(95%CI:17.2%–22.2%),whereas those utilizing the enzyme-linked immunosorbent assay(ELISA)reported a higher seroprevalence of 35.5%(95%CI:29.1%–41.8%).Geographical analysis indicated higher seroprevalence in the South Central and Southwest regions,whereas the East and Northwest areas reported the lowest seroprevalence.Chongqing Province reported the highest seroprevalence,reaching 44.9%(95%CI:43.4%–46.0%),followed by Xinjiang,Hainan,and Guizhou,whereas the lowest was observed in Shandong Province(3.5%,95%CI:1.7%–6.1%).These findings provide important epidemiological evidence that can inform strategies for the prevention and control of T.gondii infection in swine populations,with a focus on high-risk populations and geographical areas.This imperative contributes substantially to the improvement of both food safety and public health.展开更多
Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to...Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to rely on bipolar electrodes with superior performance.Cation-disordered rocksalt(DRX)Li_(2)FeTiO_(4)shows promising properties as symmetric electrodes,based on the ability of iron to undergo multiple electrochemical reactions over a wide voltage window.Unfortunately,this cation-disordered structure would not provide a cross-path for the rapid migration of Li^(+),ultimately resulting in inferior electrochemical dynamics and cycle stability.Herein,Li_(2)FeTiO_(4)nanoparticles assembled by ultrafine nanocrystals are synthesized via a sol-gel method through an orderly reaction regulation strategy of precursor reactants.Such ultrafine nanocrystals increase the active sites to promote the reversibility of multi-cationic(e.g.,stable Fe^(2+)/Fe^(3+),Ti^(3+)/Ti^(4+)and moderated Fe^(3+)/Fe^(4+))and anionic redox,and maintain the DRX structure well during the cycling process.The half cells with nano-sized Li_(2)FeTiO_(4)as the cathode/anode exhibit a high reversible capacity of 127.8/500.8 mAh/g,respectively.Besides,the Li_(2)FeTiO_(4)//Li_(2)FeTiO_(4)symmetric full cell could provide a reversible capacity of 95.4 mAh/g at 0.1 A/g after 200 cycles.This hierarchical self-assembly by nanocrystal strategy could offer effective guidance for high-performance electrode design for rechargeable secondary batteries.展开更多
The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains...The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains paramount in the accurate acquisition of the neutron time spectrum.Therefore,it is imperative for neutron logging instruments to establish a dead-time correction method that is not only uncomplicated but also practical and caters to various logging sites.This study has formulated an innovative equation for determining dead time and introduced a dead-time correction method for the neutron time spectrum,called the“dual flux method.”Using this approach,a logging instrument captures two neutron time spectra under disparate neutron fluxes.By carefully selecting specific“windows”on the neutron time spectrum,the dead time can be accurately ascertained.To substantiate its efficacy and discern the influencing factors,experiments were conducted utilizing a deuterium-tritium(D-T)neutron source,a Helium-3(3He)detector,and polyethylene shielding to collate and analyze the neutron time spectrum under varying neutron fluxes(at high voltages).The findings underscore that the“height”and“spacing”of the two windows are the most pivotal influencing factors.Notably,the“height”(fd)should surpass 2,and the“spacing”twd should exceed 200μs.The dead time of the 3 He detector determined in the experiment was 7.35μs.After the dead-time correction,the deviation of the decay coefficients from the theoretical values for the neutron time spectrum under varying neutron fluxes decreased from 12.4%to within 5%.Similarly,for the PFNUL instrument,the deviation in the decay coefficients decreased from 22.94 to 0.49%after correcting for the dead-time effect.These results demonstrate the exceptional efficacy of the proposed method in ensuring precise uranium quantification.The dual flux method was experimentally validated as a universal approach applicable to pulsed neutron logging instruments and holds immense significance for uranium exploration.展开更多
This study is based on the Extended Theory of Planned Behavior(ETPB)and focuses on the elderly population in the main urban area of Chongqing to explore their intentions and influencing factors regarding health and we...This study is based on the Extended Theory of Planned Behavior(ETPB)and focuses on the elderly population in the main urban area of Chongqing to explore their intentions and influencing factors regarding health and wellness tourism behavior.Data was collected through questionnaire surveys and field research,and SPSS 26.0 and Amos 29.0 software were used for reliability,validity analysis,and structural equation modeling testing.The study shows that behavioral attitude,perceived behavior control,and the context of health and wellness tourism have a significant positive impact on the elderly’s intentions regarding health and wellness tourism behavior,while the influence of subjective norms is not significant.In addition,subjective norms have a significant positive effect on behavioral attitudes and perceived behavioral control.Based on the research conclusions,suggestions are made to strengthen the behavioral intention of elderly tourists to participate in health and wellness tourism.展开更多
Currently,there has been significant research interest in the study of dual-ion batteries(DIBs)and hybrid dual-ion capacitors(HDICs),which utilize organic anion and metal cation reversibly stores in the cathodes and a...Currently,there has been significant research interest in the study of dual-ion batteries(DIBs)and hybrid dual-ion capacitors(HDICs),which utilize organic anion and metal cation reversibly stores in the cathodes and anodes,respectively.Nevertheless,there is a scarcity of reported DIBs or HDICs that rely on organic anions and organic cations,because the reversible storage of bulk cations is more difficult than the storage of metal cations.In this study,we provide a dual ion configuration that is ecologically beneficial,achieved by the utilization of organic-cation and organic-anion reactions on the electrodes.Remarkably,the electrochemical performance of the organic-cation based nonmetal hybrid dual-ion capacitor(ONHDIC)is noteworthy,as it demonstrates a discharge capacity of∼87 mAh g^(-1) at 2 C and a capacity retention of 91%after 700 cycles at 5 C.In addition,ONHDIC exhibits enhanced ion diffusion coefficient at elevated temperatures and demonstrates a higher discharge specific capacity of∼95 mAh g^(-1) at 2 C within the temperature range of 50–60℃.The corresponding energy density calculated based on the cathode is 201.56 Wh kg^(-1) at 50℃.In the context of a proof-of-concept,the ONHDIC pouch cell demonstrates remarkable stability and safety when subjected to continuous hammering,drilling,and destructive cutting tests.This demonstrates its promising potential for applications that prioritize environmental sustainability and safety.展开更多
As a renowned historical and cultural city,Luoyang boasts a wealth of tourism resources,including sports venues,natural landscapes,and cultural heritage sites,laying a solid foundation for the integrated development o...As a renowned historical and cultural city,Luoyang boasts a wealth of tourism resources,including sports venues,natural landscapes,and cultural heritage sites,laying a solid foundation for the integrated development of the tourism industry and sports events in recent years,with remarkable achievements in practice.However,from the perspective of sports-tourism integration,Luoyang’s event tourism still faces a prominent issue of uneven development:a surge in tourists during peak seasons,leading to overcrowded attractions,and a scarcity of visitors during off-peak seasons,resulting in idle resources.This not only leads to inefficient resource utilization but also restricts the enhancement of economic benefits and hinders sustainable development.In light of this,this paper comprehensively employs literature research,case analysis,and fieldwork methods to systematically analyze the current development status of event tourism in Luoyang within the context of sports-tourism integration.The aim is to provide theoretical and practical support for achieving high-quality and balanced development of local event tourism,offering valuable references for addressing the issue of uneven development and moving towards a sustainable future.展开更多
Twinning is an important deformation mechanism in engineering materials,which can improve the ductility and strength of alloys,especially in the case of low-plasticity Ti Al alloys.Herein,a large number ofγtwins,twin...Twinning is an important deformation mechanism in engineering materials,which can improve the ductility and strength of alloys,especially in the case of low-plasticity Ti Al alloys.Herein,a large number ofγtwins,twin intersections and adjoining twin pairs(ATPs)are formed in globularγ(γ-glob)phase after high-temperature tensile deformation.The ATPs consist of two sets of deformation twins(DTs)that are mirror symmetric about the original twin boundary(OTB).Its formation mechanism is analyzed with electron back-scattered diffraction(EBSD)and transmission electron microscope(TEM).The results reveal that the ATPs are related to the strain coordination between the DTs and the adjacent grains.Specifically,as the DT is formed in theγ-glob and impinges on the OTB,it will induce anotherγtwin(IT)in the adjacentγ-glob.The combination of the twoγtwins generates ATPs,which are formed by the transmission of a twin from one grain to the neighboring grain.Moreover,γtwins with a lower Schmidt factor(SF)of 0.2643 are preferentially formed over anotherγtwin with a higher SF(0.3098)in the sameγ-glob grain,becauseγIT accommodates the strain caused by theγDT in adjacent grain.Besides,the long-period stacking ordering(LPSO)structure of periodic contrasts 1(PC_(1))and PC_(2)are observed inγtwins,which are considered to be the intermediate phase for the formation ofγtwins.The current work elucidates the formation mechanism of ATPs in Ti Al alloy and provides insights into the formation of twins in theγ-glob.展开更多
Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(^(235)U)to detect the transient neutrons produced by fis...Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(^(235)U)to detect the transient neutrons produced by fission and then directly measure and quantify uranium;however,the stability and lifetime performance of pulsed neutron sources are the key constraints to its rapid promotion.To address these problems,this study proposes a PFNUL technique for acquiring the time spectrum of dual-energy neutrons(epithermal and thermal neutrons)from the upper and lower detection structures and establishes a novel uranium quantification algorithm based on the ratio of epithermal and thermal neutron time windows(E/T)via a mathematical-physical modeling derivation.Through simulations on well-logging models with di erent uranium contents,the starting and stopping times of the time window(Δt)for uranium quantification in the dual-energy neutron time spectrum are determined to be 200 and 800μs,respectively.The minimum radius and height of the model wells are 60 and 120 cm,respectively,and the E/T values in the time window show an excellent linear relationship with the uranium content.The scale factor is K_(E/T)=1.92 and R^(2)=0.999,which verifies the validity of the E/T uranium quantification algorithm.In addition,experiments were carried out in the Nu series of uranium standard model wells,and the results showed that under di erent neutron source yields,the E/T-based uranium quantification method reduced the relative standard deviation of the scale factor of the uranium content from 33.41%to 1.09%,compared with a single epithermal neutron quantification method.These results prove that the E/T value uranium quantification method is una ected by the change in the neutron source yield,e ectively improves the accuracy and service life of the logging instrument,and has great scientific and popularization value.展开更多
Neutron capture event imaging is a novel technique that has the potential to substantially enhance the resolution of existing imaging systems.This study provides a measurement method for neutron capture event distribu...Neutron capture event imaging is a novel technique that has the potential to substantially enhance the resolution of existing imaging systems.This study provides a measurement method for neutron capture event distribution along with multiple reconstruction methods for super-resolution imaging.The proposed technology reduces the point-spread function of an imag-ing system through single-neutron detection and event reconstruction,thereby significantly improving imaging resolution.A single-neutron detection experiment was conducted using a highly practical and efficient^(6)LiF-ZnS scintillation screen of a cold neutron imaging device in the research reactor.In milliseconds of exposure time,a large number of weak light clusters and their distribution in the scintillation screen were recorded frame by frame,to complete single-neutron detection.Several reconstruction algorithms were proposed for the calculations.The location of neutron capture was calculated using several processing methods such as noise removal,filtering,spot segmentation,contour analysis,and local positioning.The proposed algorithm achieved a higher imaging resolution and faster reconstruction speed,and single-neutron super-resolution imaging was realized by combining single-neutron detection experiments and reconstruction calculations.The results show that the resolution of the 100μm thick^(6)LiF-ZnS scintillation screen can be improved from 125 to 40 microns.This indicates that the proposed single-neutron detection and calculation method is effective and can significantly improve imaging resolution.展开更多
Position-sensitive neutron detectors play an important role in neutron scattering studies. Detectors based on ~6LiF/ZnS(Ag) scintillator and wave-shifting fiber have the advantages of high neutron detection efficiency...Position-sensitive neutron detectors play an important role in neutron scattering studies. Detectors based on ~6LiF/ZnS(Ag) scintillator and wave-shifting fiber have the advantages of high neutron detection efficiency, high position resolution,and large-area splicing, and can well meet the requirement of large area neutron detection for neutron diffractometers. An engineering detector prototype based on a ~6LiF/ZnS(Ag) scintillation screen and SiPM array readout was fabricated for the General Purpose Powder Diffractometer of China Spallation Neutron Source(CSNS). The detector has an active area of 196 mm × 444 mm, with a pixel size of 4 mm × 4 mm. The key performances of the detector prototype were tested at the BL20 neutron beam line of CSNS. The test results show that the neutron detection efficiency of the detector was 32% and 42% at wavelengths of 1.4 ? and 2.8 ?, respectively. An interpolated neutron detection efficiency of 40.2% at a wavelength of 2 ? was obtained. The tested neutron efficiency non-uniformity of the detector was 10.2%, which is less than one-half that of the current general purpose powder diffractometer scintillator neutron detectors at CSNS. This work achieves, for the first time, an efficiency uniformity of < 11% in large-area mosaic neutron detectors, alongside significant advancements in electromagnetic interference immunity and cost-effectiveness.展开更多
基金Key projects of the national natural science foundation of China(No.81930118)National support program for leading talents in traditional Chinese medicine--"Qi-huang scholars"program+1 种基金Key research projects of the 13th five-year plan of the China academy of Chinese medical sciences(No.ZZ10-022)Jiangxi province postdoctoral subsidy project(No.2018RC13).
文摘Objective:To systematically evaluate the efficacy and safety of Duhuo Jisheng decoction combined with manipulation in the treatment of lumbar disc herniation.Method:We systematically searched 8 databases at home and abroad.Literature quality of the included studies was evaluated by the bias risk assessment tool of Cochrane collaboration network,and the Meta-analysis was performed by RevMan 5.3 software.Result:A total of 427 related literature were retrieved,and 12 studies were eventually included,involving 1153 patients.All studies were in Chinese.Meta-analysis results showed that the total effective rate of Duhuo Jisheng decoction combined with manipulation in the treatment of LDH was better than that of the control group(RR=1.23,95%CI[1.17,1.29],P<0.00001).Subgroup analysis showed that Duhuo Jisheng decoction combined with manipulation had a more significant effect than conventional treatment(RR=1.34,95%CI[1.20,1.50],P<0.00001),nonsteroidal anti-inflammatory drugs(RR=1.24,95%CI[1.12,1.37],P<0.0001),and Yaotongning capsules(RR=1.19,95%CI[1.10,1.29],P<0.0001).It has obvious advantages in improving VAS scores(MD=-1.19,95%CI-1.19[-1.87,-0.51],P=0.0006),but it has no obvious advantages in improving JOA scores(MD=2.6595%CI[0.06,5.24],P=0.05).In terms of safety,Duhuo Jisheng decoction combined with manipulation treatment reported fewer adverse events.Conclusion:The Duhuo Jisheng decoction combined with manipulation treatment can effectively relieve the clinical symptoms of patients with lumbar disc herniation,with obvious clinical efficacy,and fewer adverse events.But in view of the limitations of clinical studies,there are some limitations in this study,and more studies with high quality of evidence are needed to further confirm its efficacy and safety.
基金financially supported by the National Key Re-search and Development Program of China(No.2021YFB3702604)the National Natural Science Foundation of China(No.52174377)+1 种基金the Chongqing Natural Science Foundation Project(No.CSTB2023NSCQ-MSX0824)This work was also supported by the Shaanxi Materials Analysis&Research Center and the Analytical&Testing Center of NPU.
文摘Theβsolidifiedγ-TiAl alloy holds important application value in the aerospace industry,while its com-plex phase compositions and geometric structures pose challenges to its microstructure control during the thermal-mechanical process.The microstructure evolution of Ti-43Al-4Nb-1Mo-0.2B alloy at 1200℃/0.01 s−1 was investigated to clarify the coupling role of dynamic recrystallization(DRX)and phase transformation.The results revealed that the rate of DRX inα2+γlamellar colonies was comparatively slower than that inβo+γmixed structure,instead being accompanied by intense lamellar kinking and rotation.The initiation and development rates of DRX inα2,βo,andγphases decreased sequentially.The asynchronous DRX of the various geometric structures and phase compositions resulted in the un-even deformed microstructure,and the dynamic softening induced by lamellar kinking and rotation was replaced by strengthened DRX as strain increased.Additionally,the blockyα2 phase and the terminals ofα2 lamellae were the preferential DRX sites owing to the abundant activated slip systems.Theα2→βo transformation within lamellar colonies facilitated DRX and fragment ofα2 lamellae,while theα2→γtransformation promoted the decomposition ofα2 lamellae and DRX ofγlamellae.Moreover,the var-iedβo+γmixed structures underwent complicated evolution:(1)Theγ→βo transformation occurred at boundaries of lamellar colonies,followed by simultaneous DRX ofγlamellar terminals and neighboringβo phase;(2)DRX occurred earlier within the band-likeβo phase,with the delayed DRX in enclosedγphase;(3)DRX within theβo synapses and neighboringγphase was accelerated owing to generation of elastic stress field;(4)Dispersedβo particles triggered particle stimulated nucleation(PSN)ofγphase.Eventually,atomic diffusion along crystal defects inβo andγphases caused fracture of band-likeβo phase and formation of massiveβo particles,impeding grain boundary migration and hindering DRXed grain growth ofγphase.
基金supported by the Key Research and Development Program of Science and Technology Department of Guizhou Province(No.20204Y147).
文摘Background:The prognostic significance of the chemokine receptor CCR7 in diffuse large B-cell lymphoma(DLBCL)has been reported previously.However,the detailed mechanisms of CCR7 in DLBCL,particularly regarding its interaction with lenalidomide treatment,are not fully understood.Methods:Our study utilized bioinformatics approaches to identify hub genes in SU-DHL-2 cell lines treated with lenalidomide compared to control groups.Immunohistochemical data and clinical information from 122 patients with DLBCL were analyzed to assess the correlation of CCR7 and p-ERK1/2 expression with the prognosis of DLBCL.Furthermore,in vitro and in vivo experiments were conducted to clarify the role of CCR7 in the response of DLBCL to lenalidomide treatment.Results:Our bioinformatics analysis pinpointed CCR7 as a hub gene in the context of lenalidomide treatment in DLBCL.Notably,31.14%and 36.0%(44/122)of DLBCL cases showed positive expression for CCR7 and ERK1/2 respectively,establishing them as independent prognostic factors for adverse outcomes in DLBCL via multivariate Cox regression analysis.Additionally,our studies demonstrated that the external application of the protein CCL21 promoted proliferation,migration,invasion,and activation of the ERK1/2 pathway in SU-DHL-2 and OCI-LY3 cell lines with high levels of CCR7 expression.This effect was mitigated by CCR7 silencing through siRNA,application of ERK inhibitors,or lenalidomide treatment.In vivo experiments reinforced the efficacy of lenalidomide,significantly reducing tumor growth rate,tumor mass,serum total LDH levels,and expression of CCR7 and p-ERK1/2 in a SUDHL-2 xenograft model in nude mice(p<0.05).Conclusion:Our study clarifies the potential role of the CCL21/CCR7/ERK1/2 axis in the therapeutic effects of lenalidomide in DLBCL treatment.
基金Supported by the Liaoning Province Natural Science Fund Guidance Plan,No.20180551193(In part)the Shenyang Science and Technology Project,No.17-230-9-16
文摘Liver metastasis （LM） is one of the major causes of death in patients with colorectal cancer （CRC）. Approxi-mately 60% of CRC patients develop LM during the course of their illness. About 85% of these patients have unresectable disease at the time of presenta-tion. Surgical resection is currently the only curative treatment for patients with colorectal LM （CRLM）. In recent years, with the help of modern multimodality therapy including systemic chemotherapy, radiation therapy, and surgery, the outcomes of CRLM treatment have signifcantly improved. This article summarizes the current status of surgical treatment of CRLM including evaluation of resectability, treatment for resectable LM, conversion therapy and liver transplantation for unresectable cases, liver resection for recurrent CRLM and elderly patients, and surgery for concomitanthepatic and extra-hepatic metastatic disease （EHMD）. We believe that with the help of modern multimodality therapy, an aggressive oncosurgical approach should be implemented as it has the possibility of achieving a cure, even when EHMD is present in patients with CRLM.
基金supported by the National Key R&D Program of China(2021YFD1200304).
文摘The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the primary line of defense in maintaining physiological equilibrium,the epidermis of the porpoise is expected to have undergone structural adaptations due to the shift from the marine to the freshwater environment.This study compared the microstructural and ultrastructural features of the epidermis of YFP and its marine counterpart,the East Asian finless porpoise(Neophocaena asiaeorientalis sunameri,Pilleri&Gihr,1975;EAFP).Microscopic structural observations and statistical analyses of the epidermal thickness demonstrated no significant differences in the cell structure or distribution between the two porpoise species.However,the epidermis of the YFP contained more abundant stratum basale cells.The outermost lipid stratum corneum exhibited a thinner cell layer with wider neutral lipid droplets to resist the passive entry of water molecules in the hypotonic environment.In contrast,for the EAFp,a more uniformly arranged stratum basale in the epidermis led to denser keratin fibers and robust desmosomes within each epidermal layer at the ultrastructural level.This tight arrangement of cells can reduce transepidermal water loss(TEWL)in an environment with higher osmotic pressure.In conclusion,the 2 finless porpoise species appear to employ different epidermal mechanisms to adapt to their distinct osmotic environments.The YFP appears to possess a"lipid waterproofing"epidermal structure,while the EAFP possesses a"thick and compact water-retaining"epidermal structure to copewithpotentialwaterloss.
基金supported by the National Natural Science Foundation of China(Nos.52274392 and 52104381)Natural Science Foundation of Hubei Province(No.2023AFB023)Knowledge Innovation Program of Wuhan-Basi Research(No.2023010201010133).
文摘The integration of boronizing and austempering termed boro-austempering treatment is a new processing route for preparing high strength bainitic steel with high surface hardness and high corrosion resistance.The microstructure and properties of a medium-carbon bainitic steel prepared by boro-austempering treatment were characterized and analyzed.The results show that a single Fe_(2)B layer on bainite substrate was obtained with surface hardness of~1400 HV,and the critical load for adhesive failure of borided layer reached 73.6 N.The silicon-rich α-Fe phase in transition zone was clarified as ferrite,which was formed at the beginning stage of cooling process from boronizing to low-temperature bainite transformation.Moreover,the relative potential differences between Fe_(2)B and bainite matrix,and ferrite and bainite matrix were 75 and 92 mV,respectively,with bainite matrix acting as active anode,indicating that the corrosion resistances of Fe2B and ferrite were better than that of bainite.
基金supported by the National Natural Science Foundation of China(No.52070149)Shaanxi Innovative Research Team for Key Science and Technology(No.2023-CXTD-36)+1 种基金Shaanxi Province Key Program for International S&T Cooperation Projects(No.2024GH-ZDXM-04)the Bureau of Science and Technology of Xi’an City of China(No.23SFSF0011).
文摘Anaerobic ammonia oxidation(Anammox)is an economical and sustainablewastewater nitrogen removal technology,and its application in the mainstream process is the inevitable trend of the development of Anammox.However,how to effectively enriching Anammox bacteria from the activated sludge remains challenging and restricts its extensive applications.In this study,the rapid and efficient enrichment of Anammox bacteriawas achieved by raising the reflux ratio and nitrogen loading rate(NLR)using conventional activated sludge as the inoculant.In the screening phase(days 1–90),the reflux ratio was increased to discharge partial floc sludge,resulting in the relative abundance of Candidatus Brocadiaceae increased from0.04%to 22.54%,which effectively reduced thematrix and spatial competition between other microorganisms and Anammox bacteria.On day 90,the stoichiometric ratio of the Anammox process closely approached the theoretical value of 1:1.32:0.26,indicating that the Anammox reaction was the primary nitrogen removal process in the system.In the enrichment phase(days 91–238),the NLR increased from 0.43 to 1.20 kgN/(m^(3)·d)and removal efficiency was 71.89%,resulting in the relative abundance of Candidatus Brocadiaceae increased to 61.27%on day 180.The reactor operated steadily from days 444 to 498,maintaining the nitrogen removal rate(NRR)of 3.00 kgN/(m^(3)·d)and achieving successful sludge granulation with the particle size of 392.4μm.In short,this study provided a simple and efficient approach for enriching Anammox bacteria from the activated sludge,supporting to start an Anammox process efficiently.
基金supported by the National Key Research and Development Program of China(No.2021YFF0500600)National Natural Science Foundation of China(No.22309165),Natural Science Foundation of Henan Province(No.232300420296)Key Scientific Research Project Plan of Henan Provincial Higher Education Institutions(No.25B430006).
文摘Lithium-sulfur batteries(LSBs)have attracted significant attention due to their high theoretical energy density and low-cost raw materials.However,LSBs still face various challenges in practical applications,particularly the shuttle effect,electrode passivation,and slow kinetics.In recent years,trisulfur radicals(TRs),important intermediates in LSBs,have emerged as a promising and beyond-traditional solution to these problems,which serves as a mediated catalyst to improve the electrochemical performance of LSBs.As a system that is inconsistent with the catalytic conversion process discussed in the traditional LSBs,this review focuses on the generation,detection,promotion,and catalytic roles of TRs,especially emphasizing the formation of TRs in solid-state lapis lazuli analogs and discussing the pros and cons of high donor number solvents and/or their co-solvents in stabilizing TRs.Strategies involving homogeneous/heterogeneous catalysts are discussed for increment of TRs and enhancing catalytic reactions in LSBs.Ultimately,given TRs’significant potential as a key factor in enhancing the performance of LSBs,future perspectives and outlooks are provided to guide the further development of TRs in LSBs.This review provides valuable insights into the design of electrolytes and catalysts for increment of TRs,paving the new practical direction and way for advanced LSBs.
文摘BACKGROUND Despite advances in the use of in vitro fertilization-embryo transfer(ET)in couples with infertility,recurrent implantation failure(RIF)after ET is still a major problem affecting women,with great psychological and economic burdens for the patient and his/her family.AIM To investigate the psychological burden(anxiety and depression)and evaluate the clinical benefits of endometrial receptivity testing(ERT)in patients experiencing RIF following frozen-thawed ET.METHODS A retrospective cohort study analyzed 371 patients experiencing RIF after assisted reproductive treatment at the First People’s Hospital of Changde City between January 2021 and June 2024.Demographic and clinical data were systematically collected through standardized questionnaires.Psychological assessment utilized validated instruments:The Self-Rating Depression Scale for depression evaluation and the Self-Rating Anxiety Scale for anxiety assessment.Participants were stratified by psychological status(anxiety/non-anxiety and depression/nondepression)to analyze influencing factors for anxiety and depression.The cohort was further categorized into the ERT and non-ERT groups based on ERT implementation to comparatively analyze their clinical outcomes.Additionally,they were divided into clinical and nonclinical pregnancy groups to identify factors affecting clinical pregnancy using univariate and multivariate logistic regression models.Compared with the non-ERT group,the 226 patients who underwent ERT-guided ET achieved a higher clinical pregnancy rate,thicker endometrium on transfer day,fewer embryos transferred,and a lower miscarriage rate.RESULTS The study identified a substantial psychological burden,with anxiety prevalence at 55.0%(mean Self-Rating Anxiety Scale score,50.89±9.34)and depression at 61.2%(mean Self-Rating Depression Scale score,55.55±9.48).Multivariate analysis identified annual household income>100000 yuan as protective factors against both anxiety and depression,whereas advanced maternal age(>35 years)and multiple implantation failures(≥3)served as risk factors.Additionally,anxiety-specific risk factors included prolonged infertility treatment(>5 years)and the spouse’s status as an only child.As to depression-specific risks,chronic infertility(>3 years)and higher educational attainment(college/bachelor’s degree or higher)were key determinants,whereas urban residence was a protective factor.Age>35 years was a risk factor for clinical pregnancy in patients experiencing RIF,whereas blastocyst-stage ET,a higher number of embryos transferred,and thicker endometrium were protective factors.CONCLUSION Patients experiencing RIF are particularly susceptible to anxiety and depression,and advanced maternal age and multiple implantation failures represent salient risk factors.Clinicians should implement proactive and evidencebased interventions to mitigate these psychological burdens.For patients experiencing RIF,ERT-guided ET demonstrates significant potential to improve assisted reproductive outcomes.
基金supported by the National Key Research and Development Program of China(2022YFE0114400).
文摘Toxoplasma gondii(T.gondii)is a globally distributed parasite that can infect a diversity of warm-blooded animals,including swine and humans.Infection in swine poses a considerable threat to food safety and public health.The aim of this meta-analysis was to estimate the seroprevalence of T.gondii infection in the swine population in China from 2000 to 2023 and to examine potential factors associated with infection.A total of 112 studies were included,collectively involving 145,152 swine samples originating from 26 provinces.The pooled seroprevalence was 26.0%(95%CI:23.3%–28.7%).Stratified analysis based on diagnostic methods revealed that studies using the indirect hemagglutination assay(IHA)reported a seroprevalence of 19.7%(95%CI:17.2%–22.2%),whereas those utilizing the enzyme-linked immunosorbent assay(ELISA)reported a higher seroprevalence of 35.5%(95%CI:29.1%–41.8%).Geographical analysis indicated higher seroprevalence in the South Central and Southwest regions,whereas the East and Northwest areas reported the lowest seroprevalence.Chongqing Province reported the highest seroprevalence,reaching 44.9%(95%CI:43.4%–46.0%),followed by Xinjiang,Hainan,and Guizhou,whereas the lowest was observed in Shandong Province(3.5%,95%CI:1.7%–6.1%).These findings provide important epidemiological evidence that can inform strategies for the prevention and control of T.gondii infection in swine populations,with a focus on high-risk populations and geographical areas.This imperative contributes substantially to the improvement of both food safety and public health.
基金supported by the National Natural Science Foundation of China(No.22278347)the Excellent Doctoral Student Research Innovation Project of Xinjiang University of China(No.XJU2022BS048)the Postgraduate Innovation Project of Xinjiang Uygur Autonomous Region of China(No.XJ2023G027)。
文摘Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to rely on bipolar electrodes with superior performance.Cation-disordered rocksalt(DRX)Li_(2)FeTiO_(4)shows promising properties as symmetric electrodes,based on the ability of iron to undergo multiple electrochemical reactions over a wide voltage window.Unfortunately,this cation-disordered structure would not provide a cross-path for the rapid migration of Li^(+),ultimately resulting in inferior electrochemical dynamics and cycle stability.Herein,Li_(2)FeTiO_(4)nanoparticles assembled by ultrafine nanocrystals are synthesized via a sol-gel method through an orderly reaction regulation strategy of precursor reactants.Such ultrafine nanocrystals increase the active sites to promote the reversibility of multi-cationic(e.g.,stable Fe^(2+)/Fe^(3+),Ti^(3+)/Ti^(4+)and moderated Fe^(3+)/Fe^(4+))and anionic redox,and maintain the DRX structure well during the cycling process.The half cells with nano-sized Li_(2)FeTiO_(4)as the cathode/anode exhibit a high reversible capacity of 127.8/500.8 mAh/g,respectively.Besides,the Li_(2)FeTiO_(4)//Li_(2)FeTiO_(4)symmetric full cell could provide a reversible capacity of 95.4 mAh/g at 0.1 A/g after 200 cycles.This hierarchical self-assembly by nanocrystal strategy could offer effective guidance for high-performance electrode design for rechargeable secondary batteries.
基金supported by the National Natural Science Foundation of China(No.42374226)Jiangxi Provincial Natural Science Foundation(Nos.20232BAB201043 and 20232BCJ23006)+2 种基金Nuclear Energy Development Project(20201192-01)National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing(ECUT)(2024QZ-TD-09)Fundamental Science on Radioactive Geology and Exploration Technology Laboratory(2022RGET20).
文摘The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains paramount in the accurate acquisition of the neutron time spectrum.Therefore,it is imperative for neutron logging instruments to establish a dead-time correction method that is not only uncomplicated but also practical and caters to various logging sites.This study has formulated an innovative equation for determining dead time and introduced a dead-time correction method for the neutron time spectrum,called the“dual flux method.”Using this approach,a logging instrument captures two neutron time spectra under disparate neutron fluxes.By carefully selecting specific“windows”on the neutron time spectrum,the dead time can be accurately ascertained.To substantiate its efficacy and discern the influencing factors,experiments were conducted utilizing a deuterium-tritium(D-T)neutron source,a Helium-3(3He)detector,and polyethylene shielding to collate and analyze the neutron time spectrum under varying neutron fluxes(at high voltages).The findings underscore that the“height”and“spacing”of the two windows are the most pivotal influencing factors.Notably,the“height”(fd)should surpass 2,and the“spacing”twd should exceed 200μs.The dead time of the 3 He detector determined in the experiment was 7.35μs.After the dead-time correction,the deviation of the decay coefficients from the theoretical values for the neutron time spectrum under varying neutron fluxes decreased from 12.4%to within 5%.Similarly,for the PFNUL instrument,the deviation in the decay coefficients decreased from 22.94 to 0.49%after correcting for the dead-time effect.These results demonstrate the exceptional efficacy of the proposed method in ensuring precise uranium quantification.The dual flux method was experimentally validated as a universal approach applicable to pulsed neutron logging instruments and holds immense significance for uranium exploration.
基金Chongqing University of Science and Technology 2024 Postgraduate Innovation Program(YKJCX2420803)。
文摘This study is based on the Extended Theory of Planned Behavior(ETPB)and focuses on the elderly population in the main urban area of Chongqing to explore their intentions and influencing factors regarding health and wellness tourism behavior.Data was collected through questionnaire surveys and field research,and SPSS 26.0 and Amos 29.0 software were used for reliability,validity analysis,and structural equation modeling testing.The study shows that behavioral attitude,perceived behavior control,and the context of health and wellness tourism have a significant positive impact on the elderly’s intentions regarding health and wellness tourism behavior,while the influence of subjective norms is not significant.In addition,subjective norms have a significant positive effect on behavioral attitudes and perceived behavioral control.Based on the research conclusions,suggestions are made to strengthen the behavioral intention of elderly tourists to participate in health and wellness tourism.
基金financially supported by the National Key Re-search and Development Program of China(No.2022YFB2402600)the National Natural Science Foundation of China(No.52125105)+5 种基金the National Natural Science Foundation of China(NSFC)/Hong Kong Research Grants Council(RGC)Joint Research Scheme(Nos.N_CityU104/20 and 52061160484)the Science and Technology Planning Project of Guangdong Province(Nos.2021TQ05L894,2023A1515030160,and 2022A1515011778)the Shenzhen Science and Technology Planning Project(Nos.JSGG20211108092801002,JSGG20220831104004008,SGDX20230116092055008,and KCXST20221021111606016)the Research and Innovation Group of Guangdong University of Education(No.2024KYCXTD014)the Tertiary Education Scientific Research Project of Guangzhou Mu-nicipal Education Bureau(No.202234850)the Key Scientific Research Projects of General Universities in Guangdong Province(No.2021KCXTD086).
文摘Currently,there has been significant research interest in the study of dual-ion batteries(DIBs)and hybrid dual-ion capacitors(HDICs),which utilize organic anion and metal cation reversibly stores in the cathodes and anodes,respectively.Nevertheless,there is a scarcity of reported DIBs or HDICs that rely on organic anions and organic cations,because the reversible storage of bulk cations is more difficult than the storage of metal cations.In this study,we provide a dual ion configuration that is ecologically beneficial,achieved by the utilization of organic-cation and organic-anion reactions on the electrodes.Remarkably,the electrochemical performance of the organic-cation based nonmetal hybrid dual-ion capacitor(ONHDIC)is noteworthy,as it demonstrates a discharge capacity of∼87 mAh g^(-1) at 2 C and a capacity retention of 91%after 700 cycles at 5 C.In addition,ONHDIC exhibits enhanced ion diffusion coefficient at elevated temperatures and demonstrates a higher discharge specific capacity of∼95 mAh g^(-1) at 2 C within the temperature range of 50–60℃.The corresponding energy density calculated based on the cathode is 201.56 Wh kg^(-1) at 50℃.In the context of a proof-of-concept,the ONHDIC pouch cell demonstrates remarkable stability and safety when subjected to continuous hammering,drilling,and destructive cutting tests.This demonstrates its promising potential for applications that prioritize environmental sustainability and safety.
文摘As a renowned historical and cultural city,Luoyang boasts a wealth of tourism resources,including sports venues,natural landscapes,and cultural heritage sites,laying a solid foundation for the integrated development of the tourism industry and sports events in recent years,with remarkable achievements in practice.However,from the perspective of sports-tourism integration,Luoyang’s event tourism still faces a prominent issue of uneven development:a surge in tourists during peak seasons,leading to overcrowded attractions,and a scarcity of visitors during off-peak seasons,resulting in idle resources.This not only leads to inefficient resource utilization but also restricts the enhancement of economic benefits and hinders sustainable development.In light of this,this paper comprehensively employs literature research,case analysis,and fieldwork methods to systematically analyze the current development status of event tourism in Luoyang within the context of sports-tourism integration.The aim is to provide theoretical and practical support for achieving high-quality and balanced development of local event tourism,offering valuable references for addressing the issue of uneven development and moving towards a sustainable future.
基金financially supported by the National Natural Science Foundation of China(No.52174377)the China Postdoctoral Science Foundation(No.GZC20240524)+2 种基金the China Postdoctoral Science Foundation(No.2024M750998)the National Key Research and Development Program of China(No.2021YFB3702603)the National Natural Science Foundation of China(NSFC)(No.51371049)。
文摘Twinning is an important deformation mechanism in engineering materials,which can improve the ductility and strength of alloys,especially in the case of low-plasticity Ti Al alloys.Herein,a large number ofγtwins,twin intersections and adjoining twin pairs(ATPs)are formed in globularγ(γ-glob)phase after high-temperature tensile deformation.The ATPs consist of two sets of deformation twins(DTs)that are mirror symmetric about the original twin boundary(OTB).Its formation mechanism is analyzed with electron back-scattered diffraction(EBSD)and transmission electron microscope(TEM).The results reveal that the ATPs are related to the strain coordination between the DTs and the adjacent grains.Specifically,as the DT is formed in theγ-glob and impinges on the OTB,it will induce anotherγtwin(IT)in the adjacentγ-glob.The combination of the twoγtwins generates ATPs,which are formed by the transmission of a twin from one grain to the neighboring grain.Moreover,γtwins with a lower Schmidt factor(SF)of 0.2643 are preferentially formed over anotherγtwin with a higher SF(0.3098)in the sameγ-glob grain,becauseγIT accommodates the strain caused by theγDT in adjacent grain.Besides,the long-period stacking ordering(LPSO)structure of periodic contrasts 1(PC_(1))and PC_(2)are observed inγtwins,which are considered to be the intermediate phase for the formation ofγtwins.The current work elucidates the formation mechanism of ATPs in Ti Al alloy and provides insights into the formation of twins in theγ-glob.
基金supported by the National Natural Science Foundation of China(No.42374226)Jiangxi Provincial Natural Science Foundation(Nos.20232BAB201043,gpyc20240073,and 20232BCJ23006)+2 种基金Nuclear Energy Development Project(20201192-01)Fundamental Science on Radioactive Geology and Exploration Technology Laboratory(2022RGET20)National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing(ECUT)(2024QZ-TD-09)。
文摘Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(^(235)U)to detect the transient neutrons produced by fission and then directly measure and quantify uranium;however,the stability and lifetime performance of pulsed neutron sources are the key constraints to its rapid promotion.To address these problems,this study proposes a PFNUL technique for acquiring the time spectrum of dual-energy neutrons(epithermal and thermal neutrons)from the upper and lower detection structures and establishes a novel uranium quantification algorithm based on the ratio of epithermal and thermal neutron time windows(E/T)via a mathematical-physical modeling derivation.Through simulations on well-logging models with di erent uranium contents,the starting and stopping times of the time window(Δt)for uranium quantification in the dual-energy neutron time spectrum are determined to be 200 and 800μs,respectively.The minimum radius and height of the model wells are 60 and 120 cm,respectively,and the E/T values in the time window show an excellent linear relationship with the uranium content.The scale factor is K_(E/T)=1.92 and R^(2)=0.999,which verifies the validity of the E/T uranium quantification algorithm.In addition,experiments were carried out in the Nu series of uranium standard model wells,and the results showed that under di erent neutron source yields,the E/T-based uranium quantification method reduced the relative standard deviation of the scale factor of the uranium content from 33.41%to 1.09%,compared with a single epithermal neutron quantification method.These results prove that the E/T value uranium quantification method is una ected by the change in the neutron source yield,e ectively improves the accuracy and service life of the logging instrument,and has great scientific and popularization value.
基金supported by the National Natural Science Foundation of China(Nos.12205271,12075217,U20B2011,and 51978218)Sichuan Science and Technology Program(No.2019ZDZX0010)the National Key R&D Program of China(No.2022YFA1604002).
文摘Neutron capture event imaging is a novel technique that has the potential to substantially enhance the resolution of existing imaging systems.This study provides a measurement method for neutron capture event distribution along with multiple reconstruction methods for super-resolution imaging.The proposed technology reduces the point-spread function of an imag-ing system through single-neutron detection and event reconstruction,thereby significantly improving imaging resolution.A single-neutron detection experiment was conducted using a highly practical and efficient^(6)LiF-ZnS scintillation screen of a cold neutron imaging device in the research reactor.In milliseconds of exposure time,a large number of weak light clusters and their distribution in the scintillation screen were recorded frame by frame,to complete single-neutron detection.Several reconstruction algorithms were proposed for the calculations.The location of neutron capture was calculated using several processing methods such as noise removal,filtering,spot segmentation,contour analysis,and local positioning.The proposed algorithm achieved a higher imaging resolution and faster reconstruction speed,and single-neutron super-resolution imaging was realized by combining single-neutron detection experiments and reconstruction calculations.The results show that the resolution of the 100μm thick^(6)LiF-ZnS scintillation screen can be improved from 125 to 40 microns.This indicates that the proposed single-neutron detection and calculation method is effective and can significantly improve imaging resolution.
基金Project supported by the National Natural Science Foundation of China (Grant No. 12275181)Guangdong Basic and Applied Basic Research Foundation (Grant No. 2022B1515120071)+1 种基金Promotion Project of Scientific Research Capability of Key Construction Disciplines in Guangdong Province (Grant No. 2022ZDJS118)Natural Science Foundation of Top Talent SZTU (Grant No. GDRC202205)。
文摘Position-sensitive neutron detectors play an important role in neutron scattering studies. Detectors based on ~6LiF/ZnS(Ag) scintillator and wave-shifting fiber have the advantages of high neutron detection efficiency, high position resolution,and large-area splicing, and can well meet the requirement of large area neutron detection for neutron diffractometers. An engineering detector prototype based on a ~6LiF/ZnS(Ag) scintillation screen and SiPM array readout was fabricated for the General Purpose Powder Diffractometer of China Spallation Neutron Source(CSNS). The detector has an active area of 196 mm × 444 mm, with a pixel size of 4 mm × 4 mm. The key performances of the detector prototype were tested at the BL20 neutron beam line of CSNS. The test results show that the neutron detection efficiency of the detector was 32% and 42% at wavelengths of 1.4 ? and 2.8 ?, respectively. An interpolated neutron detection efficiency of 40.2% at a wavelength of 2 ? was obtained. The tested neutron efficiency non-uniformity of the detector was 10.2%, which is less than one-half that of the current general purpose powder diffractometer scintillator neutron detectors at CSNS. This work achieves, for the first time, an efficiency uniformity of < 11% in large-area mosaic neutron detectors, alongside significant advancements in electromagnetic interference immunity and cost-effectiveness.
