Fe reducing bacteria(FRB),through extracellular electron transfer(EET)pathway,can reduce Fe(III)nanoparticles,thereby affecting the migration,transformation,and degradation of pollutants.However,the interaction of Fe(...Fe reducing bacteria(FRB),through extracellular electron transfer(EET)pathway,can reduce Fe(III)nanoparticles,thereby affecting the migration,transformation,and degradation of pollutants.However,the interaction of Fe(III)nanoparticles with the most commonly identified FRB,Geobacter sulfurreducens PCA,remains poorly understood.Herein,we demonstrated that the synergistic role of outer membrane proteins and periplasmic proteins in the EET process for-Fe_(2)O_(3),Fe3O4,and𝛽α-FeOOH nanoparticles by construction of multiple gene knockout strain.oxpG(involved in the type II secretion system)and omcST(outer membrane c-type cytochrome)medi-ated pathways accounted for approximately 67%of the total reduction of𝛼α-Fe_(2)O_(3) nanoparticles.The residual reduction of𝛼α-Fe_(2)O_(3) nanoparticles in∆oxpG-omcST strain was likely caused by redox-active substances in cell supernatant.Conversely,the reduction of dissolved Fe(III)was almost unaffected in∆oxpG-omcST strain at the same concentration.However,at high dissolved Fe(III)concentration,the reduction significantly decreased due to the formation of Fe(III)nanoparticles,suggesting that this EET process is specific to Fe(III)nanoparticles.Overall,our study provided a more comprehensive understanding for the EET pathways between G.sulfurreducens PCA and different Fe(III)species,enriching our knowledge on the role of microorganisms in iron biogeochemical cycles and remediation strategies of pollutants.展开更多
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies...Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies.展开更多
Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure throug...Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency.展开更多
Coal seam gas content is frequently measured in quantity during underground coal mining operation and coalbed methane(CBM)exploration as a significant basic parameter.Due to the calculation error of lost gas and resid...Coal seam gas content is frequently measured in quantity during underground coal mining operation and coalbed methane(CBM)exploration as a significant basic parameter.Due to the calculation error of lost gas and residual gas in the direct method,the efficiency and accuracy of the current methods are not inadequate to the large area multi-point measurement of coal seam gas content.This paper firstly deduces a simplified theoretical dynamic model for calculating lost gas based on gas dynamic diffusion theory.Secondly,the effects of various factors on gas dynamic diffusion from coal particle are experimentally studied.And sampling procedure of representative coal particle is improved.Thirdly,a new estimation method of residual gas content based on excess adsorption and competitive adsorption theory is proposed.The results showed that the maximum error of calculating the losing gas content by using the new simplified model is only 4%.Considering the influence of particle size on gas diffusion law,the particle size of the collected coal sample is below 0.25 mm,which improves the measurement speed and reflects the safety representativeness of the sample.The determination time of gas content reduced from 36 to 3 h/piece.Moreover,the absolute error is 0.15–0.50 m^3/t,and the relative error is within 5%.A new engineering method for determining the coal seam gas content is developed according to the above research.展开更多
Mobile edge computing(MEC) is a cloud server running at the edge of a mobile network, which can effectively reduce network communication delay. However, due to the numerous edge servers and devices in the MEC, there m...Mobile edge computing(MEC) is a cloud server running at the edge of a mobile network, which can effectively reduce network communication delay. However, due to the numerous edge servers and devices in the MEC, there may be multiple servers and devices that can provide services to the same user simultaneously. This paper proposes a userside adaptive user service deployment algorithm ASD(Adaptive Service Deployment) based on reinforcement learning algorithms. Without relying on complex system information, it can master only a few tasks and users. In the case of attributes, perform effective service deployment decisions, analyze and redefine the key parameters of existing algorithms, and dynamically adjust strategies according to task types and available node types to optimize user experience delay. Experiments show that the ASD algorithm can implement user-side decision-making for service deployment. While effectively improving parameter settings in the traditional Multi-Armed Bandit algorithm,it can reduce user-perceived delay and enhance service quality compared with other strategies.展开更多
Objective:IDH-mutant lower-grade gliomas(LGGs,grade 2 or 3)eventually transform into secondary grade 4 astrocytomas(sAIDHmut/G4).Here,we sought to describe the transformation time,risk factors,and outcomes in malignan...Objective:IDH-mutant lower-grade gliomas(LGGs,grade 2 or 3)eventually transform into secondary grade 4 astrocytomas(sAIDHmut/G4).Here,we sought to describe the transformation time,risk factors,and outcomes in malignant transformation of IDHmutant LGGs.Methods:We screened data for 108 patients with sAIDHmut/G4 in the Chinese Glioma Genome Atlas who had initial IDH-mutant LGGs and underwent reoperation during 2005–2021.We evaluated the transformation time from IDH-mutant LGGs to sAIDHmut/G4,and associated risk factors and outcomes.Malignant transformation was defined as pathological confirmation of grade 4 astrocytoma.Results:The median age of the 108 patients with IDH-mutant LGGs was 35 years(range,19–54);the median age at transformation was 40 years(range,25–62);and the median follow-up time for all patients was 146 months(range,121–171).The average transformation time was 58.8 months for all patients with LGGs(range,5.9–208.1);63.5 and 51.9 months for grade 2 and 3 gliomas,respectively;and 58.4 and 78.1 months for IDH-mutant/1p/19q-non-codeleted astrocytomas and IDH-mutant/1p/19q-codeleted oligodendrogliomas,respectively.Univariate and multivariate analysis indicated that radiotherapy[hazard ratio(HR),0.29;95%confidence interval(CI),0.137–0.595;P=0.001]and non-A blood type(HR,0.37;95%CI,0.203–0.680;P=0.001)were protective factors against delayed malignant transformation.Radiotherapy was associated with improved survival after transformation(HR,0.44;95%CI,0.241–0.803;P=0.008),overall survival(HR,0.50;95%CI,0.265–0.972;P=0.041),and progression-free survival(HR,0.25;95%CI,0.133–0.479;P<0.0001)in patients with IDH-mutant gliomas.Conclusions:Radiotherapy is associated with delayed malignant transformation and improved survival in patients with IDHmutant gliomas.展开更多
The multiscale micro-nano pores in coal can result in the ultra-low permeability of coal,which restricts the efficiency of gas extraction.It is difficult for the conventional seepage-enhancement measures to affect the...The multiscale micro-nano pores in coal can result in the ultra-low permeability of coal,which restricts the efficiency of gas extraction.It is difficult for the conventional seepage-enhancement measures to affect the nanoscale pores within the coal matrix.Thermal stimulation can reach deep into the micro-nano pores within coal matrix to improve the permeability.Therefore,it is important to study the diffusivity and permeability of the multiscale micro-nano pores at different temperatures.In this study,the experiments of diffusion-seepage measured by the methods of GRI(Gas Research Institution)and steady-state were conducted using a cylindrical coal at different temperatures and pressures.The experimental results show that the apparent diffusion coefficient of cylindrical coal is not constant but variable dynamically;and the classical diffusion model fails to describe the full-time process of gas flow accurately.On this basis,a model of multiscale dynamic apparent diffusion-seepage that can accurately describe the full-time flow process was proposed.As is observed,the apparent permeability attenuates dynamically with time without stress loading,and the initial apparent permeability and the attenuation coefficient increase monotonically with the rise of temperature.Under the stress constraint,the steady-state permeability increases after a decrease as the temperature rises,displaying a“U-shaped”pattern.Without stress constraint,the increasing temperature causes the exterior multiscale pores to expand outward by different degrees so as to increase permeability,while the interior micro-nano pores show three inward and outward expansion mechanisms.Under stress constraint,at low temperature and high effective stress,the increasing temperature causes pores to expand inward and the permeability decreases accordingly.When temperature continues to increase,coal expands outward because the effective stress is counteracted by the thermal stress,leading to an increase in permeability.This study is of significance for thermal gas extraction engineering.展开更多
In this paper,a delayed two-species predator-prey system with stage structure and diffiusion is investigated.Based on the continuation theorem of coincidence degree theory,the suficient conditions for the existence of...In this paper,a delayed two-species predator-prey system with stage structure and diffiusion is investigated.Based on the continuation theorem of coincidence degree theory,the suficient conditions for the existence of positiveω-periodic solution to the system are derived.The numerical simulation of an example verifies our main result.展开更多
Background:As molecular advances have deepened the knowledge on low-grade glioma(LGG),we investigated the effect of higher radiation dose on the survival of IDH-wildtype(IDHwt)LGG.Methods:In the current study,52 IDHwt...Background:As molecular advances have deepened the knowledge on low-grade glioma(LGG),we investigated the effect of higher radiation dose on the survival of IDH-wildtype(IDHwt)LGG.Methods:In the current study,52 IDHwt LGG patients who received radiotherapy were enrolled from the Chinese Glioma Genome Atlas dataset.Radiation doses>54 Gy were defined as high-dose,whereas doses≤54 Gy were defined as low-dose.We performed univariate and multivariate survival analyses to examine the prognostic role of high-dose radiotherapy.Results:In total,the radiation dose ranged from 48.6 Gy to 61.2 Gy,with a median of 55.8 Gy,and 31 patients were grouped into high-dose radiation.Univariate survival analysis indicated that high-dose radiotherapy(p=0.015),tumors located in the frontal lobe(p=0.009),and pathology of astrocytoma(p=0.037)were significantly prognostic factors for overall survival.In multivariate survival analysis,high-dose radiotherapy(p=0.028)and tumors located in the frontal lobe(p=0.016)were independently associated with better overall survival.Conclusions:In conclusion,high-dose radiotherapy independently improved the survival of IDHwt LGG.This can guide treatments for glioma with known molecular characteristics.展开更多
Glioma of the brain is a kind of tumor originating from neuroglial cells.It is the most common primary intracranial tumor,accounting for~30%of all central nervous system tumors and 80% of malignant brain tumors.Glioma...Glioma of the brain is a kind of tumor originating from neuroglial cells.It is the most common primary intracranial tumor,accounting for~30%of all central nervous system tumors and 80% of malignant brain tumors.Glioma is characterized by high disability and recurrence rates.The disease seriously threatens the life of patients,afects their quality of life,and brings a heavy economic and psychological burden to patients,families,and society.With the progression of molecular genetic testing technology and the completion of various clinical trials,the classifcation scheme for glioma is increasingly well established.Diagnosis and treatment regimens,including traditional and new regimens,are becoming increasingly specialized and standardized.The purpose is to develop a clinical diagnosis and treatment guideline for glioma in the Chinese population suitable for Chinese doctors and the general population based on domestic and international glioma research progress.Thus,domestic practitioners in the feld can obtain current information and provide better service to patients with glioma,promoting the development of domestic clinical medicine and basic research on glioma.展开更多
Plant-based milk is considered a healthy and environmentally sustainable option.In order to solve the physical and chemical instability problem of most plant milk and increase the chance of consumer acceptance of the ...Plant-based milk is considered a healthy and environmentally sustainable option.In order to solve the physical and chemical instability problem of most plant milk and increase the chance of consumer acceptance of the flavor,this experiment used soybean as raw material,fructo-oligosaccharides(FOS)as prebiotics,and added kombucha for fermentation.The microbial composition,functional components,antioxidant capacity,physicochemical properties and flavor relationship of fermented soy milk at different fermentation times(up to 96 h)were studied by high-throughput sequencing,laser confocal scanning imaging,and gas chromatography-mass spectrometry.According to the results,the synbiotic interaction of FOS and kombucha consortium promoted the growth of yeast and lactic acid bacteria in soy milk.The ideal fermentation time was 84 h.At this time,fermented soy milk added with FOS displayed increasedβ-glucosidase activity(by 68.10 mU/mL),isoflavones mainly represented by genistein content(by 612.41%),and DPPH radical scavenging activity(by 25.02%).Furthermore,the addition of FOS intensified the sour taste of the 84 h-fermented soy milk.The content of hexanal was reduced,while favorable flavor substances,such as citric acid and linalool,were also produced.Soymilk fermented with kombucha and FOS provides an opportunity to explore the physical and chemical characteristics and the mechanism of flavor formation in multi-strain co-fermentation systems and to develop commercial plant-based fermentation products.展开更多
Background: Risk factors and treatments for brain metastasis (BM) in patients with adenocarcinoma have not been fully profiled in previous studies because of the enrolment of patients with tumours of mixed histology. ...Background: Risk factors and treatments for brain metastasis (BM) in patients with adenocarcinoma have not been fully profiled in previous studies because of the enrolment of patients with tumours of mixed histology. Thus, we specifically addressed the issue in patients with adenocarcinoma. Methods: Clinical data for 373 patients with pathologically confirmed adenocarcinoma were studied retrospectively. Factors including age (≤60 vs.＞60), gender (male vs. female), stage at diagnosis, T status (T1-2 vs. T3-4), N status (N0-1 vs. N2-3), epidermal growth factor receptor (EGFR) mutation status (wild-type vs. mutant) and smoking status (never vs. current) were analyzed. Results: In multivariate analysis, age (P=0.006) and N status (P=0.041) were independent risk factors for BM. In patients with BM, adding systemic therapy to local therapy improved median post-brain-metastasis survival (mPBMS) (P=0.02). However, if stratification was conducted according to the recursive partitioning analysis (RPA) classification or graded prognostic assessment (GPA) scoring, only patients in RPA class Ⅱ (P=0.020) or with GPA score 1.5-2.5 (P=0.032) could benefit from local plus systemic therapy. Those who received both pemetrexed and tyrosine kinase inhibitors (TKIs) as systemic therapies had a longer mPBMS than those who received TKIs alone, regardless of whether local therapy was applied. In patients with EGFR-sensitive mutations, TKIs therapy led to a longer mPBMS than conventional chemotherapy (P=0.002). Conclusions: Adenocarcinoma patients who were younger than 60 years of age and those with N2-3 disease have a significantly higher risk of BM. The addition of systemic therapy to local therapy can significantly prolong mPBMS, but the survival benefit confined in certain populations. Patients with opportunity to receive both pemetrexed and TKIs had the longest mPBMS.展开更多
Background High-grade gliomas(HGGs)have a rapid relapse and short survival.Studies have identified many clinical characteristics and biomarkers associated with progression-free survival(PFS)and over-survival(OS).Howev...Background High-grade gliomas(HGGs)have a rapid relapse and short survival.Studies have identified many clinical characteristics and biomarkers associated with progression-free survival(PFS)and over-survival(OS).However,there has not yet a comprehensive study on survival after the first progression(SAP).Methods From CGGA and TCGA,319 and 308 HGGs were confirmed as the first progression.The data on clinical characteristics and biomarkers were analyzed in accordance with OS,PFS,and SAP.Results Analysis of 319 patients from CGGA,significant predictors of improved OS/PFS/SAP were WHO grade,MGMT promoter methylation,and Ki-67 expression in univariate analysis.Further multivariate analysis showed MGMT promoter methylation and Ki-67 expression were independent predictors.However,an analysis of 308 patients from TCGA found MGMT promoter methylation is the only prognostic marker.A longer SAP was observed in patients with methylated MGMT promoter after standard chemoradiotherapy.In our data,HGGs could be divided into low,intermediate,and high-risk groups for SAP by MGMT methylation and Ki-67 expression.Conclusions Patients with MGMT promoter methylation have a prolonger SAP after standard chemoradiotherapy.HGGs could be divided into low,intermediate,and high-risk groups for SAP according to MGMT status and Ki-67 expression.展开更多
The indentation technique is widely used in measuring the mechanical properties of soft matter at the microscale or nanoscale,but still faces challenges by these unique properties as well as the consequent strong surf...The indentation technique is widely used in measuring the mechanical properties of soft matter at the microscale or nanoscale,but still faces challenges by these unique properties as well as the consequent strong surface adhesion, including the strong nonlinear effect, unclear judgment of the contact point, difficulties in estimating the contact area, and the risk of the indenter piercing the sample. Here we propose a two-step method to solve these problems: lay a hard film on a soft matter, and obtain the viscoelastic properties of this soft matter through the indentation response of this composite structure. We first establish a theoretical indentation model of the hard film-soft substrate system based on the theory of plates, elastic-viscoelastic correspondence principle and Boltzmann superposition principle. To verify the correctness of this method, we measure the mechanical properties of the methyl vinyl silicone rubber(MVSR) covered by a Cu nanofilm. Finally, we test the effectiveness and error sensitivity of this method with the finite element method(FEM). The results show that our method can accurately measure the mechanical properties of soft matter, while effectively circumventing the problems of the traditional indentation technique.展开更多
Continuous lifelong acquisition,updating,and finetuning of knowledge and skills is of crucial significance for the survival of humans.However,current neuromorphic devices exhibit obvious catastrophic forgetting when r...Continuous lifelong acquisition,updating,and finetuning of knowledge and skills is of crucial significance for the survival of humans.However,current neuromorphic devices exhibit obvious catastrophic forgetting when restimulated by new information.This remains a challenge for neuromorphic devices and artificial intelligence to achieve continuous learning.Herein,we propose an electric-induced cycloelimination strategy to realize an organic transistor nociceptor that can simulate synaptic and structural plasticity.The system benefits from the ring-opening characteristics of cross-linked poly(vinyl cinnamate)under a strong pulse voltage,during which new energy-level trap states are formed.The prepared organic transistor nociceptors exhibit both structural and synaptic plasticity.They simulate the characteristics of human nociceptors,including threshold,relaxation,sensitization,and maladaptation behavior.For the first time,we have simulated and explored the structural plasticity behavior in organisms based on electronic devices.More remarkably,the transistor nociceptors realize the reinput of information without forgetting the initial informa tion.The strategy developed for the preparation of organic transistor nociceptors provides insights for addressing the catastrophic forgetting in the lifelong learning of intelligent neuromorphic devices.展开更多
The two most common inherited forms of colorectal cancer(CRC)are familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.They are caused by germline mutations in the APC and mismatch repair genes,...The two most common inherited forms of colorectal cancer(CRC)are familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.They are caused by germline mutations in the APC and mismatch repair genes,respectively.1 The simultaneous inheritance of both an APC gene mutation and a mismatch repair gene mutation is very rare.In this study,we reported a coinheritance of mutations in the APC and MLH1 genes in a 20-year-old patient with CRC and multiple polyposes.We described for the first time the somatic mutational profile of a colorectal tumor harboring concurrent germline mutations in the APC and MLH1 genes.展开更多
基金supported by the National Key Research and Development Project(No.2020YFA0907500)the National Natural Science Foundation of China(No.22476206)+1 种基金the supports from the National Young Top-Notch Talents(No.W03070030)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y202011).
文摘Fe reducing bacteria(FRB),through extracellular electron transfer(EET)pathway,can reduce Fe(III)nanoparticles,thereby affecting the migration,transformation,and degradation of pollutants.However,the interaction of Fe(III)nanoparticles with the most commonly identified FRB,Geobacter sulfurreducens PCA,remains poorly understood.Herein,we demonstrated that the synergistic role of outer membrane proteins and periplasmic proteins in the EET process for-Fe_(2)O_(3),Fe3O4,and𝛽α-FeOOH nanoparticles by construction of multiple gene knockout strain.oxpG(involved in the type II secretion system)and omcST(outer membrane c-type cytochrome)medi-ated pathways accounted for approximately 67%of the total reduction of𝛼α-Fe_(2)O_(3) nanoparticles.The residual reduction of𝛼α-Fe_(2)O_(3) nanoparticles in∆oxpG-omcST strain was likely caused by redox-active substances in cell supernatant.Conversely,the reduction of dissolved Fe(III)was almost unaffected in∆oxpG-omcST strain at the same concentration.However,at high dissolved Fe(III)concentration,the reduction significantly decreased due to the formation of Fe(III)nanoparticles,suggesting that this EET process is specific to Fe(III)nanoparticles.Overall,our study provided a more comprehensive understanding for the EET pathways between G.sulfurreducens PCA and different Fe(III)species,enriching our knowledge on the role of microorganisms in iron biogeochemical cycles and remediation strategies of pollutants.
基金supported by the National Natural Science Foundation of Shandong(No.ZR2020ZD20)the National Natural Science Foundation of China(No.22193051)+1 种基金the National Young Top-Notch Talents(No.W03070030)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y202011).
文摘Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies.
基金supported by the program for National Natural Science Foundation of China (Nos. 52174173, 52274188, and 52104190)the Joint Funds of the National Natural Science Foundation of China (No. U24A2091)+1 种基金The Natural Science Foundation of Henan Polytechnic University (No. B2021-2)Double FirstClass Initiative of Safety and Energy Engineering (Henan Polytechnic University) (Nos. AQ20240703 and AQ20230304)。
文摘Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency.
基金the National Natural Science Foundation of China(51774119,51374095,and 51604092)the primary research projects of critical scientific research in Henan Colleges and Universities(19zx003)+1 种基金Program for Innovative Research Team in University of Ministry of Education of China(IRT_16R22)State Key Laboratory Cultivation Base for Gas Geology and Gas Control(Henan Polytechnic University)(WS2018A02)。
文摘Coal seam gas content is frequently measured in quantity during underground coal mining operation and coalbed methane(CBM)exploration as a significant basic parameter.Due to the calculation error of lost gas and residual gas in the direct method,the efficiency and accuracy of the current methods are not inadequate to the large area multi-point measurement of coal seam gas content.This paper firstly deduces a simplified theoretical dynamic model for calculating lost gas based on gas dynamic diffusion theory.Secondly,the effects of various factors on gas dynamic diffusion from coal particle are experimentally studied.And sampling procedure of representative coal particle is improved.Thirdly,a new estimation method of residual gas content based on excess adsorption and competitive adsorption theory is proposed.The results showed that the maximum error of calculating the losing gas content by using the new simplified model is only 4%.Considering the influence of particle size on gas diffusion law,the particle size of the collected coal sample is below 0.25 mm,which improves the measurement speed and reflects the safety representativeness of the sample.The determination time of gas content reduced from 36 to 3 h/piece.Moreover,the absolute error is 0.15–0.50 m^3/t,and the relative error is within 5%.A new engineering method for determining the coal seam gas content is developed according to the above research.
基金supported in part by the Industrial Internet Innovation and Development Project "Industrial robot external safety enhancement device"(TC200H030)the Cooperation project between Chongqing Municipal undergraduate universities and institutes affiliated to CAS (HZ2021015)
文摘Mobile edge computing(MEC) is a cloud server running at the edge of a mobile network, which can effectively reduce network communication delay. However, due to the numerous edge servers and devices in the MEC, there may be multiple servers and devices that can provide services to the same user simultaneously. This paper proposes a userside adaptive user service deployment algorithm ASD(Adaptive Service Deployment) based on reinforcement learning algorithms. Without relying on complex system information, it can master only a few tasks and users. In the case of attributes, perform effective service deployment decisions, analyze and redefine the key parameters of existing algorithms, and dynamically adjust strategies according to task types and available node types to optimize user experience delay. Experiments show that the ASD algorithm can implement user-side decision-making for service deployment. While effectively improving parameter settings in the traditional Multi-Armed Bandit algorithm,it can reduce user-perceived delay and enhance service quality compared with other strategies.
基金supported bygrants from the Beijing Hospitals Authority Youth Programme(Grant No.QML20190506)the Capital Health Development Research Project(Grant No.2020-2-1072).
文摘Objective:IDH-mutant lower-grade gliomas(LGGs,grade 2 or 3)eventually transform into secondary grade 4 astrocytomas(sAIDHmut/G4).Here,we sought to describe the transformation time,risk factors,and outcomes in malignant transformation of IDHmutant LGGs.Methods:We screened data for 108 patients with sAIDHmut/G4 in the Chinese Glioma Genome Atlas who had initial IDH-mutant LGGs and underwent reoperation during 2005–2021.We evaluated the transformation time from IDH-mutant LGGs to sAIDHmut/G4,and associated risk factors and outcomes.Malignant transformation was defined as pathological confirmation of grade 4 astrocytoma.Results:The median age of the 108 patients with IDH-mutant LGGs was 35 years(range,19–54);the median age at transformation was 40 years(range,25–62);and the median follow-up time for all patients was 146 months(range,121–171).The average transformation time was 58.8 months for all patients with LGGs(range,5.9–208.1);63.5 and 51.9 months for grade 2 and 3 gliomas,respectively;and 58.4 and 78.1 months for IDH-mutant/1p/19q-non-codeleted astrocytomas and IDH-mutant/1p/19q-codeleted oligodendrogliomas,respectively.Univariate and multivariate analysis indicated that radiotherapy[hazard ratio(HR),0.29;95%confidence interval(CI),0.137–0.595;P=0.001]and non-A blood type(HR,0.37;95%CI,0.203–0.680;P=0.001)were protective factors against delayed malignant transformation.Radiotherapy was associated with improved survival after transformation(HR,0.44;95%CI,0.241–0.803;P=0.008),overall survival(HR,0.50;95%CI,0.265–0.972;P=0.041),and progression-free survival(HR,0.25;95%CI,0.133–0.479;P<0.0001)in patients with IDH-mutant gliomas.Conclusions:Radiotherapy is associated with delayed malignant transformation and improved survival in patients with IDHmutant gliomas.
基金Doctoral Foundation of Henan Polytechnic University,Grant/Award Number:B2021-7Key Science and Technology Project of Henan Province,Grant/Award Number:222102320017+3 种基金State Key Laboratory Cultivation Base for Gas Geology and Gas Control(Henan Polytechnic University),Grant/Award Number:WS2021A06National Natural Science Foundation of China,Grant/Award Number:52174173Key Scientific Research Projects of Colleges and Universities in Henan Province,Grant/Award Number:22B620002Fundamental Research Funds for the Universities of Henan Province,Grant/Award Number:NSFRF180305。
文摘The multiscale micro-nano pores in coal can result in the ultra-low permeability of coal,which restricts the efficiency of gas extraction.It is difficult for the conventional seepage-enhancement measures to affect the nanoscale pores within the coal matrix.Thermal stimulation can reach deep into the micro-nano pores within coal matrix to improve the permeability.Therefore,it is important to study the diffusivity and permeability of the multiscale micro-nano pores at different temperatures.In this study,the experiments of diffusion-seepage measured by the methods of GRI(Gas Research Institution)and steady-state were conducted using a cylindrical coal at different temperatures and pressures.The experimental results show that the apparent diffusion coefficient of cylindrical coal is not constant but variable dynamically;and the classical diffusion model fails to describe the full-time process of gas flow accurately.On this basis,a model of multiscale dynamic apparent diffusion-seepage that can accurately describe the full-time flow process was proposed.As is observed,the apparent permeability attenuates dynamically with time without stress loading,and the initial apparent permeability and the attenuation coefficient increase monotonically with the rise of temperature.Under the stress constraint,the steady-state permeability increases after a decrease as the temperature rises,displaying a“U-shaped”pattern.Without stress constraint,the increasing temperature causes the exterior multiscale pores to expand outward by different degrees so as to increase permeability,while the interior micro-nano pores show three inward and outward expansion mechanisms.Under stress constraint,at low temperature and high effective stress,the increasing temperature causes pores to expand inward and the permeability decreases accordingly.When temperature continues to increase,coal expands outward because the effective stress is counteracted by the thermal stress,leading to an increase in permeability.This study is of significance for thermal gas extraction engineering.
基金Supported by the Basis and Frontier Science Research Foundation of Henan Province(072300410096)the Natural Science Foundation of Education Department of Henan Province(2009A110023)the Youth Foundation of Zhoukou Normal University
文摘In this paper,a delayed two-species predator-prey system with stage structure and diffiusion is investigated.Based on the continuation theorem of coincidence degree theory,the suficient conditions for the existence of positiveω-periodic solution to the system are derived.The numerical simulation of an example verifies our main result.
基金This work was supported by The National Natural Science Foundation of China(Grant Numbers:82001778)The Capital Medical Development Research Fund(Grant Numbers:2020-2-1072).
文摘Background:As molecular advances have deepened the knowledge on low-grade glioma(LGG),we investigated the effect of higher radiation dose on the survival of IDH-wildtype(IDHwt)LGG.Methods:In the current study,52 IDHwt LGG patients who received radiotherapy were enrolled from the Chinese Glioma Genome Atlas dataset.Radiation doses>54 Gy were defined as high-dose,whereas doses≤54 Gy were defined as low-dose.We performed univariate and multivariate survival analyses to examine the prognostic role of high-dose radiotherapy.Results:In total,the radiation dose ranged from 48.6 Gy to 61.2 Gy,with a median of 55.8 Gy,and 31 patients were grouped into high-dose radiation.Univariate survival analysis indicated that high-dose radiotherapy(p=0.015),tumors located in the frontal lobe(p=0.009),and pathology of astrocytoma(p=0.037)were significantly prognostic factors for overall survival.In multivariate survival analysis,high-dose radiotherapy(p=0.028)and tumors located in the frontal lobe(p=0.016)were independently associated with better overall survival.Conclusions:In conclusion,high-dose radiotherapy independently improved the survival of IDHwt LGG.This can guide treatments for glioma with known molecular characteristics.
基金supported by China Anti-Cancer Association (CACA).
文摘Glioma of the brain is a kind of tumor originating from neuroglial cells.It is the most common primary intracranial tumor,accounting for~30%of all central nervous system tumors and 80% of malignant brain tumors.Glioma is characterized by high disability and recurrence rates.The disease seriously threatens the life of patients,afects their quality of life,and brings a heavy economic and psychological burden to patients,families,and society.With the progression of molecular genetic testing technology and the completion of various clinical trials,the classifcation scheme for glioma is increasingly well established.Diagnosis and treatment regimens,including traditional and new regimens,are becoming increasingly specialized and standardized.The purpose is to develop a clinical diagnosis and treatment guideline for glioma in the Chinese population suitable for Chinese doctors and the general population based on domestic and international glioma research progress.Thus,domestic practitioners in the feld can obtain current information and provide better service to patients with glioma,promoting the development of domestic clinical medicine and basic research on glioma.
基金funded by the Fellowship of China Postdoctoral Special Science Foundation[2022T150199]the Heilongjiang Province“Tens of Millions”Project Science and Technology Major Special Projects[2019ZX08B01].
文摘Plant-based milk is considered a healthy and environmentally sustainable option.In order to solve the physical and chemical instability problem of most plant milk and increase the chance of consumer acceptance of the flavor,this experiment used soybean as raw material,fructo-oligosaccharides(FOS)as prebiotics,and added kombucha for fermentation.The microbial composition,functional components,antioxidant capacity,physicochemical properties and flavor relationship of fermented soy milk at different fermentation times(up to 96 h)were studied by high-throughput sequencing,laser confocal scanning imaging,and gas chromatography-mass spectrometry.According to the results,the synbiotic interaction of FOS and kombucha consortium promoted the growth of yeast and lactic acid bacteria in soy milk.The ideal fermentation time was 84 h.At this time,fermented soy milk added with FOS displayed increasedβ-glucosidase activity(by 68.10 mU/mL),isoflavones mainly represented by genistein content(by 612.41%),and DPPH radical scavenging activity(by 25.02%).Furthermore,the addition of FOS intensified the sour taste of the 84 h-fermented soy milk.The content of hexanal was reduced,while favorable flavor substances,such as citric acid and linalool,were also produced.Soymilk fermented with kombucha and FOS provides an opportunity to explore the physical and chemical characteristics and the mechanism of flavor formation in multi-strain co-fermentation systems and to develop commercial plant-based fermentation products.
文摘Background: Risk factors and treatments for brain metastasis (BM) in patients with adenocarcinoma have not been fully profiled in previous studies because of the enrolment of patients with tumours of mixed histology. Thus, we specifically addressed the issue in patients with adenocarcinoma. Methods: Clinical data for 373 patients with pathologically confirmed adenocarcinoma were studied retrospectively. Factors including age (≤60 vs.＞60), gender (male vs. female), stage at diagnosis, T status (T1-2 vs. T3-4), N status (N0-1 vs. N2-3), epidermal growth factor receptor (EGFR) mutation status (wild-type vs. mutant) and smoking status (never vs. current) were analyzed. Results: In multivariate analysis, age (P=0.006) and N status (P=0.041) were independent risk factors for BM. In patients with BM, adding systemic therapy to local therapy improved median post-brain-metastasis survival (mPBMS) (P=0.02). However, if stratification was conducted according to the recursive partitioning analysis (RPA) classification or graded prognostic assessment (GPA) scoring, only patients in RPA class Ⅱ (P=0.020) or with GPA score 1.5-2.5 (P=0.032) could benefit from local plus systemic therapy. Those who received both pemetrexed and tyrosine kinase inhibitors (TKIs) as systemic therapies had a longer mPBMS than those who received TKIs alone, regardless of whether local therapy was applied. In patients with EGFR-sensitive mutations, TKIs therapy led to a longer mPBMS than conventional chemotherapy (P=0.002). Conclusions: Adenocarcinoma patients who were younger than 60 years of age and those with N2-3 disease have a significantly higher risk of BM. The addition of systemic therapy to local therapy can significantly prolong mPBMS, but the survival benefit confined in certain populations. Patients with opportunity to receive both pemetrexed and TKIs had the longest mPBMS.
基金funded by the National Natural Science Foundation of China(NO.82172771 to YW.L)the National Key Research and Development Program(NO.2023YFC2510005 to XG.Q).
文摘Background High-grade gliomas(HGGs)have a rapid relapse and short survival.Studies have identified many clinical characteristics and biomarkers associated with progression-free survival(PFS)and over-survival(OS).However,there has not yet a comprehensive study on survival after the first progression(SAP).Methods From CGGA and TCGA,319 and 308 HGGs were confirmed as the first progression.The data on clinical characteristics and biomarkers were analyzed in accordance with OS,PFS,and SAP.Results Analysis of 319 patients from CGGA,significant predictors of improved OS/PFS/SAP were WHO grade,MGMT promoter methylation,and Ki-67 expression in univariate analysis.Further multivariate analysis showed MGMT promoter methylation and Ki-67 expression were independent predictors.However,an analysis of 308 patients from TCGA found MGMT promoter methylation is the only prognostic marker.A longer SAP was observed in patients with methylated MGMT promoter after standard chemoradiotherapy.In our data,HGGs could be divided into low,intermediate,and high-risk groups for SAP by MGMT methylation and Ki-67 expression.Conclusions Patients with MGMT promoter methylation have a prolonger SAP after standard chemoradiotherapy.HGGs could be divided into low,intermediate,and high-risk groups for SAP according to MGMT status and Ki-67 expression.
基金the National Natural Science Foundation of China(Grant Nos.11432014,11521202,11672301,and 11890681).
文摘The indentation technique is widely used in measuring the mechanical properties of soft matter at the microscale or nanoscale,but still faces challenges by these unique properties as well as the consequent strong surface adhesion, including the strong nonlinear effect, unclear judgment of the contact point, difficulties in estimating the contact area, and the risk of the indenter piercing the sample. Here we propose a two-step method to solve these problems: lay a hard film on a soft matter, and obtain the viscoelastic properties of this soft matter through the indentation response of this composite structure. We first establish a theoretical indentation model of the hard film-soft substrate system based on the theory of plates, elastic-viscoelastic correspondence principle and Boltzmann superposition principle. To verify the correctness of this method, we measure the mechanical properties of the methyl vinyl silicone rubber(MVSR) covered by a Cu nanofilm. Finally, we test the effectiveness and error sensitivity of this method with the finite element method(FEM). The results show that our method can accurately measure the mechanical properties of soft matter, while effectively circumventing the problems of the traditional indentation technique.
基金the National Key R&D Program(grant no.2018YFA0703200)the National Natural Science Foundation of China(grant nos.61890940 and 52003274)+3 种基金the Chinese Academy of Sciences(CAS)Project for Young Scientists in Basic Research(grant no.YSBR-053)the Strategic Priority Research Program of the CAS(grant no.XDB30000000)the CAS-Croucher Funding Scheme for Joint Laboratories,the CAS Cooperation Projects(grant no.121111KYSB20200036)Lu Jiaxi international team(grant no.GJTD-2020-02).
文摘Continuous lifelong acquisition,updating,and finetuning of knowledge and skills is of crucial significance for the survival of humans.However,current neuromorphic devices exhibit obvious catastrophic forgetting when restimulated by new information.This remains a challenge for neuromorphic devices and artificial intelligence to achieve continuous learning.Herein,we propose an electric-induced cycloelimination strategy to realize an organic transistor nociceptor that can simulate synaptic and structural plasticity.The system benefits from the ring-opening characteristics of cross-linked poly(vinyl cinnamate)under a strong pulse voltage,during which new energy-level trap states are formed.The prepared organic transistor nociceptors exhibit both structural and synaptic plasticity.They simulate the characteristics of human nociceptors,including threshold,relaxation,sensitization,and maladaptation behavior.For the first time,we have simulated and explored the structural plasticity behavior in organisms based on electronic devices.More remarkably,the transistor nociceptors realize the reinput of information without forgetting the initial informa tion.The strategy developed for the preparation of organic transistor nociceptors provides insights for addressing the catastrophic forgetting in the lifelong learning of intelligent neuromorphic devices.
基金supported by the Key Research and Development Program of Anhui Province,China(No.2022e07020048)the Clinical Research Incubation Program of The Second Hospital of Anhui Medical University,China(No.2020LCZD07)+2 种基金the National Natural Science Foundation of China(No.81872438)the Program of Research and Development of Key Common Technologies and Engineering of Major Scientific and Technological Achievements in Hefei,China(No.2021YL007)the Collaborative Innovation Program of Hefei Science Center CAS(China)(No.2022HSC-CIP015).
文摘The two most common inherited forms of colorectal cancer(CRC)are familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.They are caused by germline mutations in the APC and mismatch repair genes,respectively.1 The simultaneous inheritance of both an APC gene mutation and a mismatch repair gene mutation is very rare.In this study,we reported a coinheritance of mutations in the APC and MLH1 genes in a 20-year-old patient with CRC and multiple polyposes.We described for the first time the somatic mutational profile of a colorectal tumor harboring concurrent germline mutations in the APC and MLH1 genes.
