Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after inju...Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients.展开更多
Acute mountain sickness(AMS) is an illness caused by hypoxia due to rapid ascent to altitudes above 2,500 m. Symptoms include headache,nausea, vomiting, and loss of appetite, all of which usually improve within 1 to 2...Acute mountain sickness(AMS) is an illness caused by hypoxia due to rapid ascent to altitudes above 2,500 m. Symptoms include headache,nausea, vomiting, and loss of appetite, all of which usually improve within 1 to 2 days. However,untreated AMS can progress to life-threatening conditions such as high-altitude cerebral and pulmonary edema(HACE and HAPE, respectively)^([1]).展开更多
Background The patient-reported Dimensional Anhedonia Rating Scale(DARS)has been adapted into Chinese,so there is a need to evaluate its measurement properties in a Chinese population.Aims To evaluate the reliability ...Background The patient-reported Dimensional Anhedonia Rating Scale(DARS)has been adapted into Chinese,so there is a need to evaluate its measurement properties in a Chinese population.Aims To evaluate the reliability and validity of the DARS among Chinese individuals with major depressive disorder(MDD)and its treatment sensitivity in a prospective clinical study.Methods Data were from a multicentre,prospective clinical study(NCT03294525),which recruited both patients with MDD,who were followed for 8 weeks,and healthy controls(HCs),assessed at baseline only.The analysis included confirmatory factor analysis,validity and sensitivity to change.Results Patients’mean(standard deviation(SD))age was 34.8(11.0)years,with 68.7%being female.75.2%of patients with MDD had melancholic features,followed by 63.8%with anxious distress.Patients had experienced MDD for a mean(SD)of 9.2(18)months.DARS scores covered the full range of severity with no major floor or ceiling effects.Confirmatory factor analysis showed adequate fit statistics(comparative fit index 0.976,goodness-of-fit index 0.935 and root mean square error of approximation 0.055).Convergent validity with anhedonia-related measures was confirmed.While the correlation between the DARS and the Hamilton Depression Rating Scale was not strong(r=0.31,baseline),the DARS was found to differentiate between levels of depression.Greater improvements in DARS scores were seen with the Hamilton Rating Scale for Depression responder group(effect size 1.16)compared with the non-responder group(effect size 0.46).Conclusions This study comprehensively evaluated the measurement properties of the DARS using a Chinese population with MDD.Overall,the Chinese version of DARS demonstrates good psychometric properties and has been found to be responsive to change during antidepressant treatment.The DARS is a suitable scale for assessing patient-reported anhedonia in future clinical trials.展开更多
Objective:Circulating tumor DNA(ctDNA)is increasingly being used as a potential biomarker in colorectal cancer(CRC)patients.However,the role of ctDNA in CRC prognosis prediction remains unclear.The objective is to sys...Objective:Circulating tumor DNA(ctDNA)is increasingly being used as a potential biomarker in colorectal cancer(CRC)patients.However,the role of ctDNA in CRC prognosis prediction remains unclear.The objective is to systematically assess the clinical value of ctDNA in colorectal cancer prognosis prediction throughout the treatment cycle.Methods:PubMed,Web of Science,Embase,Cochrane Library,Scopus,and clinical trials.gov database was searched from January 2016 to April 2023.Observational studies and randomized clinical trials reporting on ctDNA and prognostic outcomes in CRC patients were included.Pooled hazard risk ratios(HRs)were calculated for the primary outcomes,relapse-free survival(RFS),and overall survival(OS).Random-effects models were preferred considering the potential heterogeneity.Results:Sixty-five cohort studies were included.Association between ctDNA and shorter RFS or OS was significant,especially after the full-course treatment recommended by the guidelines(HR=8.92[95%CI:6.02-13.22],P<0.001,I^(2)=73%;HR=3.05[95%CI:1.72-5.41],P<0.001,I^(2)=48%)for all types of CRC patients.Despite the presence of heterogeneity,subgroup analyses showed that the cancer type and ctDNA detection assays may be the underlying cause.Besides,ctDNA may detect recurrence earlier than radiographic progression,but no uniform sampling time point between studies might bring bias.However,ctDNA detection did not appear to correlate with pathological complete response achievement in patients with locally advanced rectal cancer.Conclusion:ctDNA detection was significantly associated with poorer prognosis.The potential applications in prognostic prediction are promising and remain to be evaluated in other fields.展开更多
A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,wh...A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,which reduces the risk of penetrating the bulkhead.In the realm of hypervelocity impact,strain rate(>10^(5)s^(-1))effects are negligible,and fluid dynamics is employed to describe the impact process.Efficient numerical tools for precisely predicting the damage degree can greatly accelerate the design and optimization of advanced protective structures.Current hypervelocity impact research primarily focuses on the interaction between projectile and front plate and the movement of debris cloud.However,the damage mechanism of debris cloud impacts on rear plates-the critical threat component-remains underexplored owing to complex multi-physics processes and prohibitive computational costs.Existing approaches,ranging from semi-empirical equations to a machine learningbased ballistic limit prediction method,are constrained to binary penetration classification.Alternatively,the uneven data from experiments and simulations caused these methods to be ineffective when the projectile has irregular shapes and complicate flight attitude.Therefore,it is urgent to develop a new damage prediction method for predicting the rear plate damage,which can help to gain a deeper understanding of the damage mechanism.In this study,a machine learning(ML)method is developed to predict the damage distribution in the rear plate.Based on the unit velocity space,the discretized information of debris cloud and rear plate damage from rare simulation cases is used as input data for training the ML models,while the generalization ability for damage distribution prediction is tested by other simulation cases with different attack angles.The results demonstrate that the training and prediction accuracies using the Random Forest(RF)algorithm significantly surpass those using Artificial Neural Networks(ANNs)and Support Vector Machine(SVM).The RF-based model effectively identifies damage features in sparsely distributed debris cloud and cumulative effect.This study establishes an expandable new dataset that accommodates additional parameters to improve the prediction accuracy.Results demonstrate the model's ability to overcome data imbalance limitations through debris cloud features,enabling rapid and accurate rear plate damage prediction across wider scenarios with minimal data requirements.展开更多
Flat plate impact experiments are crucial in assessing the dynamic mechanical properties of materials.However,yaw angle tolerances always affect the accuracy of the results.To analyze this effect,this study conducted ...Flat plate impact experiments are crucial in assessing the dynamic mechanical properties of materials.However,yaw angle tolerances always affect the accuracy of the results.To analyze this effect,this study conducted numerical simulations and theoretical derivations of non-ideal plate impacts.By comparing the simulated results of spallation,shock wave propagation,and free surface velocity,laws governing the effect of yaw angle on the plate impact were summarized.We observed that yaw angles influence the wave-action time and the shape of the compression zone,which affects the trigger and location of spallation and the free surface velocity of the target.Additionally,the yaw angle diminishes the kinetic energy of the target.When the yaw angle exceeds 2°,a significant energy reduction occurs as the shock wave propagates,which results in insufficient energy for complete spallation.Our analyses led to proposing methods for determining the critical yaw angle in plate impact experiments and to introducing a multipoint-velocimetry approach to calculate the non-ideal impact posture of the flyer.Notably,the findings revealed that 0.2°could serve as the critical yaw angle in certain scenarios.Leveraging these research outcomes judiciously can aid in assessing experimental deviations effectively and optimizing experimental costs.展开更多
Objective:Circulating tumor DNA(ctDNA)has shown potential as a prognostic biomarker in patients with solid tumors.This study aimed to systematically summarize the global application of ctDNA in the prognostic man-agem...Objective:Circulating tumor DNA(ctDNA)has shown potential as a prognostic biomarker in patients with solid tumors.This study aimed to systematically summarize the global application of ctDNA in the prognostic man-agement of solid tumor patients and to evaluate the quality of the current studies.Methods:PubMed,Web of Science,Embase,Cochrane Library,Scopus,and clinical trials.gov databases were searched to collect cohort studies on ctDNA in the prognosis of solid tumor patients from January 2016 to May 2022.The language was limited to English.Information including general information,participants and cancer characteristics,ctDNA and outcome information were extracted.The quality of the studies was assessed using the Newcastle-Ottawa Scale checklist.Results:A total of 214 studies were included in the final analysis,encompassing 21,076 patients.The number of studies has increased annually from 2016 to 2022.The most common types of solid tumors studied were colorectal cancer(27.10%),lung cancer(20.09%),pancreatic cancer(16.82%),and breast cancer(14.02%).The top three journals by number of publications had an impact factor in 2023 greater than 10.Of the studies,the median sample size was 69(interquartile range:41-111),69.81%had a sample size<100,68.92%had a median/mean age≥60 years,and 74.05%were from developed countries.Multi-center studies accounted for 40.36%.Additionally,29.82%of the studies had a bias risk score≤6.Only 16.67%of studies on liver cancer had a bias risk score>6.The primary criteria not met by the studies included“Adequacy of follow-up of cohorts”(33.33%),“Assessment of outcome”(32.16%)and“Representativeness of the exposed cohort”(27.49%).Conclusions:The prognostic value of ctDNA in patients with solid tumors is gaining increasing attention,leading to a steady rise in the number of studies.However,many studies still suffer from small sample sizes and a lack of representativeness.Furthermore,details regarding ctDNA detection methods and results reporting are often insufficiently described.There is an urgent need to improve the quality of such research.展开更多
Isatis indigotica Fort.(Ban-Lan-Gen)is an herbal medicine prescribed for influenza treatment.However,its active components and mode of action remain mostly unknown.In the present study,erucic acid was isolated from Is...Isatis indigotica Fort.(Ban-Lan-Gen)is an herbal medicine prescribed for influenza treatment.However,its active components and mode of action remain mostly unknown.In the present study,erucic acid was isolated from Isatis indigotica Fort.,and subsequently its underlying mechanism against influenza A virus(IAV)infection was investigated in vitro and in vivo.Our results demonstrated that erucic acid exhibited broad-spectrum antiviral activity against IAV resulting from reduction of viral polymerase transcription activity.Erucic acid was found to exert inhibitory effects on IAV or viral(v)RNA-induced pro-inflam-matory mediators as well as interferons(IFNs).The molecular mechanism by which erucic acid with antiviral and anti-inflammatory properties was attributed to inactivation of NF-kB and p38 MAPK signaling.Furthermore,the NF-kB and p38 MAPK inhibitory effect of erucic acid led to diminishing the transcriptional activity of interferon-stimulated gene factor 3(ISGF-3),and thereby reducing IAV-triggered pro-inflammatory response amplification in IFN-β-sensitized cells.Additionally,IAV-or vRNA-triggered apoptosis of alveolar epithelial A549 cells was prevented by erucic acid.In vivo,erucic acid administration consistently displayed decreased lung viral load and viral antigens expression.Meanwhile,erucic acid markedly reduced CD8+cytotoxic T lymphocyte(CTL)recruitment,pro-apoptotic signaling,hyperactivity of multiple signaling pathways,and exacerbated immune inflammation in the lung,which resulted in decreased lung injury and mortality in mice with a mouse-adapted A/FM/1/47-MA(H1N1)strain infection.Our findings provided a mechanistic basis for the action of erucic acid against IAV-mediated inflammation and injury,suggesting that erucic acid may have a therapeutic potential in the treatment of influenza.展开更多
Oblique perforation of thick metallic plates by rigid projectiles with various nose shapes is studied in this paper. Two perforation mechanisms, i.e., the hole enlargement for a sharp projectile nose and the plugging ...Oblique perforation of thick metallic plates by rigid projectiles with various nose shapes is studied in this paper. Two perforation mechanisms, i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose, are considered in the proposed analytical model. It is shown that the perforation of a thick plate is dominated by several non-dimensional numbers, i.e., the impact function, the geometry function of projectile, the non-dimensional thickness of target and the impact obliquity. Explicit formulae are obtained to predict the ballistic limit, residual velocity and directional change for the oblique perforation of thick metallic plates. The proposed model is able to predict the critical condition for the occurrence of ricochet. The proposed model is validated by comparing the predictions with other existing models and independent experimental data.展开更多
Multi-scale finite element method is adopted to simulate wood compression behavior under axial and transverse loading. Representative volume elements (RVE) of wood microfibril and cell are proposed to analyze orthotro...Multi-scale finite element method is adopted to simulate wood compression behavior under axial and transverse loading. Representative volume elements (RVE) of wood microfibril and cell are proposed to analyze orthotropic mechanical behavior. Lignin, hemicellulose and crystalline-amorphous cellulose core of spruce are concerned in spruce nanoscale model. The equivalent elastic modulus and yield strength of the microfibril are gained by the RVE simulation. The anisotropism of the crystalline-amorphous cellulose core brings the microfibril buckling deformation during compression loading. The failure mechanism of the cell-wall under axial compression is related to the distribution of amorphous cellulose and crystalline cellulose. According to the spruce cell observation by scanning electron microscope, numerical model of spruce cell is established using simplified circular hole and regular hexagon arrangement respectively. Axial and transverse compression loadings are taken into account in the numerical simulations. It indicates that the compression stress-strain curves of the numerical simulation are consistent with the experimental results. The wood microstructure arrangement has an important effect on the stress plateau during compression process. Cell-wall buckling in axial compression induces the stress value drops rapidly. The wide stress plateau duration means wood is with large energy dissipation under a low stress level. The numerical results show that loading velocity affects greatly wood microstructure failure modes in axial loading. For low velocity axial compression, shear sliding is the main failure mode. For high velocity axial compression, wood occur fold and collapse. In transverse compression, wood deformation is gradual and uniform, which brings stable stress plateau.展开更多
A simplified approximate model considering rod/target material's compressibility is proposed for hypervelocity penetration.We study the effect of shockwaves on hypervelocity penetration whenever the compressibilit...A simplified approximate model considering rod/target material's compressibility is proposed for hypervelocity penetration.We study the effect of shockwaves on hypervelocity penetration whenever the compressibility of the rod is much larger,analogously,and much less than that of the target,respectively.The results show that the effect of shockwaves is insignificant up to 12 km/s,so the shockwave is neglected in the present approximate model.The Murnaghan equation of state is adopted to simulate the material behaviors in penetration and its validity is proved.The approximate model is finally reduced to an equation depending only on the penetration velocity and a simple approximate solution is achieved.The solution of the approximate model is in agreement with the result of the complete compressible model.In addition,the effect of shockwaves on hypervelocity penetration is shown to weaken material's compressibility and reduce the interface pressure of the rod/target,and thus the striking/protective performance of the rod/target is weakened,respectively.We also conduct an error analysis of the interface pressure and penetration efficiency.With a velocity change of 1.6 times the initial sound speed for the rod or target,the error of the approximate model is very small.For metallic rod-target combinations,the approximate model is applicable even at an impact velocity of 12 km/s.展开更多
Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones ...Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones by sol immobilization using polyvinyl alcohol(PVA) as protecting agent and NaBH4 as reducing agent,using carbon nanofibers with high graphitization degree(HHT) as the desired support.The synthesized catalysts were characterized by means of Transmission Electron Microscopy(TEM) and inductively coupled plasma optical emission spectroscopy(ICP-OES).TEM shows that the average particle size of the Pd-Rh nanoparticles is the range of 3-4 nm,with the presence of few large agglomerated nanoparticles.For bimetallic catalysts,EDX-STEM analysis of individual nanoparticles demonstrated the presence of random-alloyed nanoparticles even in all cases Rh content is lower than the nominal one(calculated Pd:Rh molar ratio:90-10,69-31,49-51,40-60).The catalytic performance of the Pd-Rh catalysts was evaluated in the liquid phase dehydrogenation of formic acid to H2.It was found that Pd-Rh molar ratio strongly influences the catalytic performance.Pd-rich catalysts were more active than Rh-rich ones,with the highest activity observed for Pd90:Rh10(1792 h^(-1)),whereas Pd69:Rh31(921 h^(-1)) resulted the most stable during recycling tests.Finally,Pd90:Rh10 was chosen as a representative sample for the liquid-phase hydrogenation of muconic acid using formic acid as hydrogen donor,showing good yield to adipic acid.展开更多
Lupus Nephritis(LN)is a significant risk factor for morbidity and mortality in systemic lupus erythematosus,and nephropathology is still the gold standard for diagnosing LN.To assist pathologists in evaluating histopa...Lupus Nephritis(LN)is a significant risk factor for morbidity and mortality in systemic lupus erythematosus,and nephropathology is still the gold standard for diagnosing LN.To assist pathologists in evaluating histopathological images of LN,a 2D Rényi entropy multi-threshold image segmentation method is proposed in this research to apply to LN images.This method is based on an improved Cuckoo Search(CS)algorithm that introduces a Diffusion Mechanism(DM)and an Adaptiveβ-Hill Climbing(AβHC)strategy called the DMCS algorithm.The DMCS algorithm is tested on 30 benchmark functions of the IEEE CEC2017 dataset.In addition,the DMCS-based multi-threshold image segmentation method is also used to segment renal pathological images.Experimental results show that adding these two strategies improves the DMCS algorithm's ability to find the optimal solution.According to the three image quality evaluation metrics:PSNR,FSIM,and SSIM,the proposed image segmentation method performs well in image segmentation experiments.Our research shows that the DMCS algorithm is a helpful image segmentation method for renal pathological images.展开更多
This study investigates how the debris cloud structure and hazardous fragment distribution vary with attack angle by simulating a circular cylinder projectile hypervelocity impinging on a thin plate using the finite e...This study investigates how the debris cloud structure and hazardous fragment distribution vary with attack angle by simulating a circular cylinder projectile hypervelocity impinging on a thin plate using the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method.Based on the comparison and analysis of the experimental and simulation results,the FE-SPH adaptive method was applied to address the hypervelocity yaw impact problem,and the variation law of the debris cloud structure with the attack angle was obtained.The screening criterion of the hazardous fragment at yaw impact is given by analyzing the debris formation obtained by the FE-SPH adaptive method,and the distribution characteristics of hazardous fragments and their relationship with the attack angle are given.Moreover,the velocity space was used to evaluate the distribution range and damage capability of asymmetric hazardous fragments.The maximum velocity angle was extended from fully symmetrical working conditions to asymmetrical cases to describe the asymmetrical debris cloud distribution range.In this range,the energy density was calculated to quantitatively analyze how much damage hazardous fragments inflict on the rear plate.The results showed that the number of hazardous fragments generated by the case near the 35°attack angle was the largest,the distribution range was the smallest,and the energy density was the largest.These results suggest that in this case,debris cloud generated by the impact had the strongest damage to the rear plate.展开更多
Objective: To critically evaluate and summarize the methodological quality of systematic reviews(SRs)and present objective and important outcomes on the effectiveness of traditional Chinese medicine(TCM) therapies, in...Objective: To critically evaluate and summarize the methodological quality of systematic reviews(SRs)and present objective and important outcomes on the effectiveness of traditional Chinese medicine(TCM) therapies, including Chinese herbal medicine(CHM), acupuncture, and moxibustion, for diarrheapredominant irritable bowel syndrome(IBS-D).Methods: We conducted a comprehensive literature search for SRs in 7 databases until April 16, 2022.Two reviewers independently extracted data and assessed the methodological quality of the reviews according to the Assessing the Methodological Quality of Systematic Reviews 2(AMSTAR-2), the Risk of Bias in Systematic reviews(ROBIS) tool, and the Preferred Reporting Item for Systematic Review and Meta-analysis(PRISMA) statement. The Grading of Recommendations, Assessment, Development, and Evaluation(GRADE) was used to rate the quality of evidence.Results: IBS-D patients included in 12 reviews were diagnosed in accordance with the Rome criteria, 9 reviews focused on CHM, 2 articles observed moxibustion and heat-sensitive moxibustion, 1 article studied acupuncture and CHM. The outcomes of the SRs were the effectiveness rate, the total effectiveness rate,global symptom improvement, and adverse effects. Based on AMSTAR-2, which measures the quality of methodology, all of the included studies were of low or critically low quality. According to the ROBIS tool, 10 SRs(83.33%) had a high risk of bias. With the PRISMA checklist, only 3 SRs reached over 90% compliance.Based on GRADE, most evidence was of low quality, and there was a moderate quality of evidence that the effectiveness rate of modified-Tongxie Yaofang was superior to Western medicine in the treatment of IBS-D.Conclusion: Given the suboptimal reporting and methodological quality of existing SRs, more studies are needed to clarify whether TCM therapies are more effective or safe than pharmacological medicine.Future studies should combine evidence-based medicine with TCM research according to the characteristics of TCM.展开更多
Phytosterols,which are naturally occurring in plants,have excellent nutritional and health values on lowering both the blood cholesterol level and the risk of cardiovascular diseases.Edible oils are the main source of...Phytosterols,which are naturally occurring in plants,have excellent nutritional and health values on lowering both the blood cholesterol level and the risk of cardiovascular diseases.Edible oils are the main source of daily intake of phytosterols,whereas the properties of phytosterols may vary a lot depending on their sources.During the processing of edible oil including refining and frying,phytosterol's content fluctuates,which influences the properties of the final product.Phytosterols and their derivatives undergo physical migration between different phases and chemical conversion during the processing,which reduces the quality and the commercial value of edible oils.Therein,the loss of phytosterols is the major concern in the process of neutralization and deodorization.In addition,oxidation and thermal degradation of phytosterols occur simultaneously during frying,which also reduces the content of phytosterols.Nevertheless,the oil matrix has a promoting or an inhibitory effect on the thermal oxidation of phytosterols.Therefore,various efforts have been devoted to analyzing and improving the remaining contents of phytosterols in edible oil.Regardless of the processing method,temperature plays an important role in the loss of phytosterols.At present,themain analysismethods of phytosterols include gas chromatography and liquid chromatography,inwhich the pretreatment of different types of phytosterols is also a crucial step.This review focused on the following topics comprehensively:(i)the distribution of phytosterols in the oil-containing plants and edible oils during the refining processing;(ii)the pretreatment and analysis methods of various phytosterols(free phytosterols,phytosteryl fatty acid esters,phytosteryl glycosides and acylated phytosteryl glycosides);(iii)the variation of phytosterols in process of esterification and oxidation,storage and so on.The study also proposed that the investigation in the loss and safety of phytosterols during processing of the vegetable oils should be proceeded further in combination with efficient and accurate chromatography methods.展开更多
文摘Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients.
文摘Acute mountain sickness(AMS) is an illness caused by hypoxia due to rapid ascent to altitudes above 2,500 m. Symptoms include headache,nausea, vomiting, and loss of appetite, all of which usually improve within 1 to 2 days. However,untreated AMS can progress to life-threatening conditions such as high-altitude cerebral and pulmonary edema(HACE and HAPE, respectively)^([1]).
基金supported by the National Natural Science Foundation of China(No.82371530,82171529)the Capital Health Development Special Research Project(2022-1-4111)the National Key Technology R and D Program(No.2015BAI13B01).
文摘Background The patient-reported Dimensional Anhedonia Rating Scale(DARS)has been adapted into Chinese,so there is a need to evaluate its measurement properties in a Chinese population.Aims To evaluate the reliability and validity of the DARS among Chinese individuals with major depressive disorder(MDD)and its treatment sensitivity in a prospective clinical study.Methods Data were from a multicentre,prospective clinical study(NCT03294525),which recruited both patients with MDD,who were followed for 8 weeks,and healthy controls(HCs),assessed at baseline only.The analysis included confirmatory factor analysis,validity and sensitivity to change.Results Patients’mean(standard deviation(SD))age was 34.8(11.0)years,with 68.7%being female.75.2%of patients with MDD had melancholic features,followed by 63.8%with anxious distress.Patients had experienced MDD for a mean(SD)of 9.2(18)months.DARS scores covered the full range of severity with no major floor or ceiling effects.Confirmatory factor analysis showed adequate fit statistics(comparative fit index 0.976,goodness-of-fit index 0.935 and root mean square error of approximation 0.055).Convergent validity with anhedonia-related measures was confirmed.While the correlation between the DARS and the Hamilton Depression Rating Scale was not strong(r=0.31,baseline),the DARS was found to differentiate between levels of depression.Greater improvements in DARS scores were seen with the Hamilton Rating Scale for Depression responder group(effect size 1.16)compared with the non-responder group(effect size 0.46).Conclusions This study comprehensively evaluated the measurement properties of the DARS using a Chinese population with MDD.Overall,the Chinese version of DARS demonstrates good psychometric properties and has been found to be responsive to change during antidepressant treatment.The DARS is a suitable scale for assessing patient-reported anhedonia in future clinical trials.
基金funded by the Capital’s Funds for Health Improve-ment and Research(grant number:2024-1G-4023)the Special Project for Director,China Center for Evidence Based Traditional Chinese Medicine(grant number:2020YJSZX-2)National Natural Science Foundation of China(grant number:72474008).
文摘Objective:Circulating tumor DNA(ctDNA)is increasingly being used as a potential biomarker in colorectal cancer(CRC)patients.However,the role of ctDNA in CRC prognosis prediction remains unclear.The objective is to systematically assess the clinical value of ctDNA in colorectal cancer prognosis prediction throughout the treatment cycle.Methods:PubMed,Web of Science,Embase,Cochrane Library,Scopus,and clinical trials.gov database was searched from January 2016 to April 2023.Observational studies and randomized clinical trials reporting on ctDNA and prognostic outcomes in CRC patients were included.Pooled hazard risk ratios(HRs)were calculated for the primary outcomes,relapse-free survival(RFS),and overall survival(OS).Random-effects models were preferred considering the potential heterogeneity.Results:Sixty-five cohort studies were included.Association between ctDNA and shorter RFS or OS was significant,especially after the full-course treatment recommended by the guidelines(HR=8.92[95%CI:6.02-13.22],P<0.001,I^(2)=73%;HR=3.05[95%CI:1.72-5.41],P<0.001,I^(2)=48%)for all types of CRC patients.Despite the presence of heterogeneity,subgroup analyses showed that the cancer type and ctDNA detection assays may be the underlying cause.Besides,ctDNA may detect recurrence earlier than radiographic progression,but no uniform sampling time point between studies might bring bias.However,ctDNA detection did not appear to correlate with pathological complete response achievement in patients with locally advanced rectal cancer.Conclusion:ctDNA detection was significantly associated with poorer prognosis.The potential applications in prognostic prediction are promising and remain to be evaluated in other fields.
基金supported by National Natural Science Foundation of China(Grant No.12432018,12372346)the Innovative Research Groups of the National Natural Science Foundation of China(Grant No.12221002).
文摘A typical Whipple shield consists of double-layered plates with a certain gap.The space debris impacts the outer plate and is broken into a debris cloud(shattered,molten,vaporized)with dispersed energy and momentum,which reduces the risk of penetrating the bulkhead.In the realm of hypervelocity impact,strain rate(>10^(5)s^(-1))effects are negligible,and fluid dynamics is employed to describe the impact process.Efficient numerical tools for precisely predicting the damage degree can greatly accelerate the design and optimization of advanced protective structures.Current hypervelocity impact research primarily focuses on the interaction between projectile and front plate and the movement of debris cloud.However,the damage mechanism of debris cloud impacts on rear plates-the critical threat component-remains underexplored owing to complex multi-physics processes and prohibitive computational costs.Existing approaches,ranging from semi-empirical equations to a machine learningbased ballistic limit prediction method,are constrained to binary penetration classification.Alternatively,the uneven data from experiments and simulations caused these methods to be ineffective when the projectile has irregular shapes and complicate flight attitude.Therefore,it is urgent to develop a new damage prediction method for predicting the rear plate damage,which can help to gain a deeper understanding of the damage mechanism.In this study,a machine learning(ML)method is developed to predict the damage distribution in the rear plate.Based on the unit velocity space,the discretized information of debris cloud and rear plate damage from rare simulation cases is used as input data for training the ML models,while the generalization ability for damage distribution prediction is tested by other simulation cases with different attack angles.The results demonstrate that the training and prediction accuracies using the Random Forest(RF)algorithm significantly surpass those using Artificial Neural Networks(ANNs)and Support Vector Machine(SVM).The RF-based model effectively identifies damage features in sparsely distributed debris cloud and cumulative effect.This study establishes an expandable new dataset that accommodates additional parameters to improve the prediction accuracy.Results demonstrate the model's ability to overcome data imbalance limitations through debris cloud features,enabling rapid and accurate rear plate damage prediction across wider scenarios with minimal data requirements.
基金supported by the Innovative Research Groups of the National Natural Science Foundation of China(Grant No.12221002)the National Natural Science Foundation of China(Grant No.12372346).
文摘Flat plate impact experiments are crucial in assessing the dynamic mechanical properties of materials.However,yaw angle tolerances always affect the accuracy of the results.To analyze this effect,this study conducted numerical simulations and theoretical derivations of non-ideal plate impacts.By comparing the simulated results of spallation,shock wave propagation,and free surface velocity,laws governing the effect of yaw angle on the plate impact were summarized.We observed that yaw angles influence the wave-action time and the shape of the compression zone,which affects the trigger and location of spallation and the free surface velocity of the target.Additionally,the yaw angle diminishes the kinetic energy of the target.When the yaw angle exceeds 2°,a significant energy reduction occurs as the shock wave propagates,which results in insufficient energy for complete spallation.Our analyses led to proposing methods for determining the critical yaw angle in plate impact experiments and to introducing a multipoint-velocimetry approach to calculate the non-ideal impact posture of the flyer.Notably,the findings revealed that 0.2°could serve as the critical yaw angle in certain scenarios.Leveraging these research outcomes judiciously can aid in assessing experimental deviations effectively and optimizing experimental costs.
基金funded by the National Natural Science Foundation of China(grant numbers:72474008,72074011)the Capital’s Funds for Health Improvement and Research(grant number:2024-1G-4023)the Special Project for Director,China Center for Evidence Based Traditional Chinese Medicine(grant number:2020YJSZX-2).
文摘Objective:Circulating tumor DNA(ctDNA)has shown potential as a prognostic biomarker in patients with solid tumors.This study aimed to systematically summarize the global application of ctDNA in the prognostic man-agement of solid tumor patients and to evaluate the quality of the current studies.Methods:PubMed,Web of Science,Embase,Cochrane Library,Scopus,and clinical trials.gov databases were searched to collect cohort studies on ctDNA in the prognosis of solid tumor patients from January 2016 to May 2022.The language was limited to English.Information including general information,participants and cancer characteristics,ctDNA and outcome information were extracted.The quality of the studies was assessed using the Newcastle-Ottawa Scale checklist.Results:A total of 214 studies were included in the final analysis,encompassing 21,076 patients.The number of studies has increased annually from 2016 to 2022.The most common types of solid tumors studied were colorectal cancer(27.10%),lung cancer(20.09%),pancreatic cancer(16.82%),and breast cancer(14.02%).The top three journals by number of publications had an impact factor in 2023 greater than 10.Of the studies,the median sample size was 69(interquartile range:41-111),69.81%had a sample size<100,68.92%had a median/mean age≥60 years,and 74.05%were from developed countries.Multi-center studies accounted for 40.36%.Additionally,29.82%of the studies had a bias risk score≤6.Only 16.67%of studies on liver cancer had a bias risk score>6.The primary criteria not met by the studies included“Adequacy of follow-up of cohorts”(33.33%),“Assessment of outcome”(32.16%)and“Representativeness of the exposed cohort”(27.49%).Conclusions:The prognostic value of ctDNA in patients with solid tumors is gaining increasing attention,leading to a steady rise in the number of studies.However,many studies still suffer from small sample sizes and a lack of representativeness.Furthermore,details regarding ctDNA detection methods and results reporting are often insufficiently described.There is an urgent need to improve the quality of such research.
基金funded by the National Natural Science Foundation of China(Grantno.81873065)the Secondary Development Projects of Guangdong Famous and Excellent TraditionalChinese Patent Medicines(Grant no.20174005)+1 种基金the Natural Science Foundation of Guangdong Province(Grant no.2018A030310172)the China Postdoctoral Science Foundation(Grant no.2017M622652,2019M652987)。
文摘Isatis indigotica Fort.(Ban-Lan-Gen)is an herbal medicine prescribed for influenza treatment.However,its active components and mode of action remain mostly unknown.In the present study,erucic acid was isolated from Isatis indigotica Fort.,and subsequently its underlying mechanism against influenza A virus(IAV)infection was investigated in vitro and in vivo.Our results demonstrated that erucic acid exhibited broad-spectrum antiviral activity against IAV resulting from reduction of viral polymerase transcription activity.Erucic acid was found to exert inhibitory effects on IAV or viral(v)RNA-induced pro-inflam-matory mediators as well as interferons(IFNs).The molecular mechanism by which erucic acid with antiviral and anti-inflammatory properties was attributed to inactivation of NF-kB and p38 MAPK signaling.Furthermore,the NF-kB and p38 MAPK inhibitory effect of erucic acid led to diminishing the transcriptional activity of interferon-stimulated gene factor 3(ISGF-3),and thereby reducing IAV-triggered pro-inflammatory response amplification in IFN-β-sensitized cells.Additionally,IAV-or vRNA-triggered apoptosis of alveolar epithelial A549 cells was prevented by erucic acid.In vivo,erucic acid administration consistently displayed decreased lung viral load and viral antigens expression.Meanwhile,erucic acid markedly reduced CD8+cytotoxic T lymphocyte(CTL)recruitment,pro-apoptotic signaling,hyperactivity of multiple signaling pathways,and exacerbated immune inflammation in the lung,which resulted in decreased lung injury and mortality in mice with a mouse-adapted A/FM/1/47-MA(H1N1)strain infection.Our findings provided a mechanistic basis for the action of erucic acid against IAV-mediated inflammation and injury,suggesting that erucic acid may have a therapeutic potential in the treatment of influenza.
文摘Oblique perforation of thick metallic plates by rigid projectiles with various nose shapes is studied in this paper. Two perforation mechanisms, i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose, are considered in the proposed analytical model. It is shown that the perforation of a thick plate is dominated by several non-dimensional numbers, i.e., the impact function, the geometry function of projectile, the non-dimensional thickness of target and the impact obliquity. Explicit formulae are obtained to predict the ballistic limit, residual velocity and directional change for the oblique perforation of thick metallic plates. The proposed model is able to predict the critical condition for the occurrence of ricochet. The proposed model is validated by comparing the predictions with other existing models and independent experimental data.
基金supported by the National Natural Science Foundation of China(Grants Nos 11302211,11390361,and 11572299).
文摘Multi-scale finite element method is adopted to simulate wood compression behavior under axial and transverse loading. Representative volume elements (RVE) of wood microfibril and cell are proposed to analyze orthotropic mechanical behavior. Lignin, hemicellulose and crystalline-amorphous cellulose core of spruce are concerned in spruce nanoscale model. The equivalent elastic modulus and yield strength of the microfibril are gained by the RVE simulation. The anisotropism of the crystalline-amorphous cellulose core brings the microfibril buckling deformation during compression loading. The failure mechanism of the cell-wall under axial compression is related to the distribution of amorphous cellulose and crystalline cellulose. According to the spruce cell observation by scanning electron microscope, numerical model of spruce cell is established using simplified circular hole and regular hexagon arrangement respectively. Axial and transverse compression loadings are taken into account in the numerical simulations. It indicates that the compression stress-strain curves of the numerical simulation are consistent with the experimental results. The wood microstructure arrangement has an important effect on the stress plateau during compression process. Cell-wall buckling in axial compression induces the stress value drops rapidly. The wide stress plateau duration means wood is with large energy dissipation under a low stress level. The numerical results show that loading velocity affects greatly wood microstructure failure modes in axial loading. For low velocity axial compression, shear sliding is the main failure mode. For high velocity axial compression, wood occur fold and collapse. In transverse compression, wood deformation is gradual and uniform, which brings stable stress plateau.
基金The work was supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(11521202)the National Outstanding Young Scientist Foundation of China(11225213)the Key Subject'Computational Solid Mechanics'of China Academy of Engineering Physics.
文摘A simplified approximate model considering rod/target material's compressibility is proposed for hypervelocity penetration.We study the effect of shockwaves on hypervelocity penetration whenever the compressibility of the rod is much larger,analogously,and much less than that of the target,respectively.The results show that the effect of shockwaves is insignificant up to 12 km/s,so the shockwave is neglected in the present approximate model.The Murnaghan equation of state is adopted to simulate the material behaviors in penetration and its validity is proved.The approximate model is finally reduced to an equation depending only on the penetration velocity and a simple approximate solution is achieved.The solution of the approximate model is in agreement with the result of the complete compressible model.In addition,the effect of shockwaves on hypervelocity penetration is shown to weaken material's compressibility and reduce the interface pressure of the rod/target,and thus the striking/protective performance of the rod/target is weakened,respectively.We also conduct an error analysis of the interface pressure and penetration efficiency.With a velocity change of 1.6 times the initial sound speed for the rod or target,the error of the approximate model is very small.For metallic rod-target combinations,the approximate model is applicable even at an impact velocity of 12 km/s.
文摘Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones by sol immobilization using polyvinyl alcohol(PVA) as protecting agent and NaBH4 as reducing agent,using carbon nanofibers with high graphitization degree(HHT) as the desired support.The synthesized catalysts were characterized by means of Transmission Electron Microscopy(TEM) and inductively coupled plasma optical emission spectroscopy(ICP-OES).TEM shows that the average particle size of the Pd-Rh nanoparticles is the range of 3-4 nm,with the presence of few large agglomerated nanoparticles.For bimetallic catalysts,EDX-STEM analysis of individual nanoparticles demonstrated the presence of random-alloyed nanoparticles even in all cases Rh content is lower than the nominal one(calculated Pd:Rh molar ratio:90-10,69-31,49-51,40-60).The catalytic performance of the Pd-Rh catalysts was evaluated in the liquid phase dehydrogenation of formic acid to H2.It was found that Pd-Rh molar ratio strongly influences the catalytic performance.Pd-rich catalysts were more active than Rh-rich ones,with the highest activity observed for Pd90:Rh10(1792 h^(-1)),whereas Pd69:Rh31(921 h^(-1)) resulted the most stable during recycling tests.Finally,Pd90:Rh10 was chosen as a representative sample for the liquid-phase hydrogenation of muconic acid using formic acid as hydrogen donor,showing good yield to adipic acid.
基金supported in part by the Natural Science Foundation of Zhejiang Province(LZ22F020005,LTGS23E070001)National Natural Science Foundation of China(62076185,U1809209).
文摘Lupus Nephritis(LN)is a significant risk factor for morbidity and mortality in systemic lupus erythematosus,and nephropathology is still the gold standard for diagnosing LN.To assist pathologists in evaluating histopathological images of LN,a 2D Rényi entropy multi-threshold image segmentation method is proposed in this research to apply to LN images.This method is based on an improved Cuckoo Search(CS)algorithm that introduces a Diffusion Mechanism(DM)and an Adaptiveβ-Hill Climbing(AβHC)strategy called the DMCS algorithm.The DMCS algorithm is tested on 30 benchmark functions of the IEEE CEC2017 dataset.In addition,the DMCS-based multi-threshold image segmentation method is also used to segment renal pathological images.Experimental results show that adding these two strategies improves the DMCS algorithm's ability to find the optimal solution.According to the three image quality evaluation metrics:PSNR,FSIM,and SSIM,the proposed image segmentation method performs well in image segmentation experiments.Our research shows that the DMCS algorithm is a helpful image segmentation method for renal pathological images.
基金supported by the National Natural Science Foundation of China(Grant No.11872118,11627901)。
文摘This study investigates how the debris cloud structure and hazardous fragment distribution vary with attack angle by simulating a circular cylinder projectile hypervelocity impinging on a thin plate using the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method.Based on the comparison and analysis of the experimental and simulation results,the FE-SPH adaptive method was applied to address the hypervelocity yaw impact problem,and the variation law of the debris cloud structure with the attack angle was obtained.The screening criterion of the hazardous fragment at yaw impact is given by analyzing the debris formation obtained by the FE-SPH adaptive method,and the distribution characteristics of hazardous fragments and their relationship with the attack angle are given.Moreover,the velocity space was used to evaluate the distribution range and damage capability of asymmetric hazardous fragments.The maximum velocity angle was extended from fully symmetrical working conditions to asymmetrical cases to describe the asymmetrical debris cloud distribution range.In this range,the energy density was calculated to quantitatively analyze how much damage hazardous fragments inflict on the rear plate.The results showed that the number of hazardous fragments generated by the case near the 35°attack angle was the largest,the distribution range was the smallest,and the energy density was the largest.These results suggest that in this case,debris cloud generated by the impact had the strongest damage to the rear plate.
基金supported by the National Key Research and Development Program of China (2019YFC1709004)。
文摘Objective: To critically evaluate and summarize the methodological quality of systematic reviews(SRs)and present objective and important outcomes on the effectiveness of traditional Chinese medicine(TCM) therapies, including Chinese herbal medicine(CHM), acupuncture, and moxibustion, for diarrheapredominant irritable bowel syndrome(IBS-D).Methods: We conducted a comprehensive literature search for SRs in 7 databases until April 16, 2022.Two reviewers independently extracted data and assessed the methodological quality of the reviews according to the Assessing the Methodological Quality of Systematic Reviews 2(AMSTAR-2), the Risk of Bias in Systematic reviews(ROBIS) tool, and the Preferred Reporting Item for Systematic Review and Meta-analysis(PRISMA) statement. The Grading of Recommendations, Assessment, Development, and Evaluation(GRADE) was used to rate the quality of evidence.Results: IBS-D patients included in 12 reviews were diagnosed in accordance with the Rome criteria, 9 reviews focused on CHM, 2 articles observed moxibustion and heat-sensitive moxibustion, 1 article studied acupuncture and CHM. The outcomes of the SRs were the effectiveness rate, the total effectiveness rate,global symptom improvement, and adverse effects. Based on AMSTAR-2, which measures the quality of methodology, all of the included studies were of low or critically low quality. According to the ROBIS tool, 10 SRs(83.33%) had a high risk of bias. With the PRISMA checklist, only 3 SRs reached over 90% compliance.Based on GRADE, most evidence was of low quality, and there was a moderate quality of evidence that the effectiveness rate of modified-Tongxie Yaofang was superior to Western medicine in the treatment of IBS-D.Conclusion: Given the suboptimal reporting and methodological quality of existing SRs, more studies are needed to clarify whether TCM therapies are more effective or safe than pharmacological medicine.Future studies should combine evidence-based medicine with TCM research according to the characteristics of TCM.
基金supported by the NationalNatural Science Foundation of China(No.31972110)the National Key R&D Program of China(No.2018YFD0401102).
文摘Phytosterols,which are naturally occurring in plants,have excellent nutritional and health values on lowering both the blood cholesterol level and the risk of cardiovascular diseases.Edible oils are the main source of daily intake of phytosterols,whereas the properties of phytosterols may vary a lot depending on their sources.During the processing of edible oil including refining and frying,phytosterol's content fluctuates,which influences the properties of the final product.Phytosterols and their derivatives undergo physical migration between different phases and chemical conversion during the processing,which reduces the quality and the commercial value of edible oils.Therein,the loss of phytosterols is the major concern in the process of neutralization and deodorization.In addition,oxidation and thermal degradation of phytosterols occur simultaneously during frying,which also reduces the content of phytosterols.Nevertheless,the oil matrix has a promoting or an inhibitory effect on the thermal oxidation of phytosterols.Therefore,various efforts have been devoted to analyzing and improving the remaining contents of phytosterols in edible oil.Regardless of the processing method,temperature plays an important role in the loss of phytosterols.At present,themain analysismethods of phytosterols include gas chromatography and liquid chromatography,inwhich the pretreatment of different types of phytosterols is also a crucial step.This review focused on the following topics comprehensively:(i)the distribution of phytosterols in the oil-containing plants and edible oils during the refining processing;(ii)the pretreatment and analysis methods of various phytosterols(free phytosterols,phytosteryl fatty acid esters,phytosteryl glycosides and acylated phytosteryl glycosides);(iii)the variation of phytosterols in process of esterification and oxidation,storage and so on.The study also proposed that the investigation in the loss and safety of phytosterols during processing of the vegetable oils should be proceeded further in combination with efficient and accurate chromatography methods.
