Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify...Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species.展开更多
A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that r...A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that regulates heading date,plant height and grain number.Here,we investigated the relationship between Ghd7 and florigen genes Hd3a and RFT1,to determine their roles in regulating heading date and grain number under different photoperiods.Our results revealed that under long-day(LD)conditions,Hd3a acts prior to RFT1 to promote heading while negatively regulating plant height and grain number.In contrast,Ghd7 positively regulates heading date,plant height,and grain number by inhibiting both Hd3a and RFT1.Under short-day(SD)conditions,the functions of Hd3a and RFT1 remain consistent with those under LD conditions,but Ghd7 does not inhibit their expression,resulting in a weaker phenotypic effect compared to Hd3a.Additionally,under both LD and SD conditions,increased Ghd7 expression enhances its inhibitory effect on Hd3a and RFT1,leading to later heading and increased grain number;however,once the heading date exceeds 94 d,grain number no longer increases.Moreover,the gn1a allele increased grain number by 16.5%to 42.5%,while combinations of the elite alleles from Ghd7,Hd3a,RFT1,and Gn1a significantly increased grain number by up to 240.9%.Therefore,we propose a new breeding strategy to optimize the heading date and grain number using the Ghd7Hd3aRFT1gn1a combination of Ghd7,Hd3a,RFT1,and Gn1a under LD conditions,and the Ghd7hd3aRFT1gn1a combination under SD conditions.This strategy improved the yield of the high-quality Northeast variety Kongyu 131(KY131)by 69.1%in Beijing and 93.7%in Hainan.This strategy will greatly improve the efficiency of north-to-south adaptation in rice,providing theoretical guidance for expanding the geographical adaptability of rice varieties.展开更多
Recently,Choe-Koo-Wang(J Funct Anal,2020,278)demonstrated the rigid phenomenon:The compact linear combination of composition operators under the Coefficient Non-cancellation Condition(CNC),implies that each difference...Recently,Choe-Koo-Wang(J Funct Anal,2020,278)demonstrated the rigid phenomenon:The compact linear combination of composition operators under the Coefficient Non-cancellation Condition(CNC),implies that each difference is compact on the weighted Bergman space in the unit disk.Motivated by the subtle connection of composition operator theory on the weighted Bergman spaces,Korenblum spaces and bounded holomorphic function spaces,we first explore the rigid phenomenon which also holds on the Korenblum space over the unit ball.Furthermore,we discuss which difference of composition operators is compact when the compact combination of composition operators does not satisfy the condition(CNC)on Korenblum spaces and bounded holomorphic function spaces over the unit ball setting.展开更多
Effective isolation between the cement sheath and the sandstone is crucial for the development and production of oil and gas wells in sandstone formations.In this study,a cement-sandstone composite(CSC)was prepared,an...Effective isolation between the cement sheath and the sandstone is crucial for the development and production of oil and gas wells in sandstone formations.In this study,a cement-sandstone composite(CSC)was prepared,and based onμ-CT three-dimensional reconstruction imaging and finite element analysis(FEA)techniques,the stress distribution and potential failure mechanism at the cement-sandstone bonding interface under axial loading were analyzed.The key findings are as follows:(1)stress concentrations are highly likely to form at the gap between the cement and sandstone interface and around interfacial voids,with Von Mises stress reaching critical levels of 18.0-20.0 MPa at these locations,significantly exceeding the stress magnitudes in well-bonded regions;(2)the phenomenon of local stress concentration driven by interfacial defects can be identified as the main basis for predicting damage location in interfacial debonding and continuous shear under axial load;(3)ensuring tight cementation at the cement-sandstone interface and minimizing interfacial voids are paramount for preventing stress-induced failure;(4)the critical Von Mises stress value of 20 MPa at the interface defect can be used as a benchmark for material selection and designed to ensure long-term integrity in oil and gas well applications subjected to similar axial loads.These findings contribute to a more accurate understanding of the failure mechanism of the cement-sandstone interface and to the precise design of material properties,thereby ensuring the long-term integrity of oil and gas well applications subjected to similar axial loads.展开更多
Understanding the mechanical properties of coal-rock-bolt(CRB)combinations at high strain rates and the anchoring mechanism of bolts is crucial for ensuring the safety of coal mining operations.However,the dynamic beh...Understanding the mechanical properties of coal-rock-bolt(CRB)combinations at high strain rates and the anchoring mechanism of bolts is crucial for ensuring the safety of coal mining operations.However,the dynamic behaviors of these combinations,especially the mechanism of action of prestressed bolts,still need to be further investigated.This study carried out split Hopkinson pressure bar(SHPB)tests on three sets of coal-rock(CR),CRB,and coal-rock-prestressed bolt(CRPB)combinations with different interface angles(β=15°,30°,45°,and 60°).The dynamic properties of the combinations were analyzed based on the stress-strain curve,energy dissipation,dynamic strength,fractal dimension of cracks,and failure mode of bolts.The test results show that a larger β will affect the stress transfer and anti-sliding ability of CR,resulting in a decrease in CR strength.The anchoring force of the bolt effectively suppresses the slip feature of CRB at the yield stage.As the strain rate increases,CRB shows a more pronounced'sudden increase'in strength,and the bolt significantly enhances its dynamic strength.The prestressed bolts enhance the dynamic strength of CRPB while weaken the effect of β.The fractal dimension of the macrocracks increases with strain rate,with smaller variations in CRB and CRPB,indicating that the bolt reduces the complexity degree of CRB and CRPB.The anchoring force of CRB depends on bolt strength,which reduces the slip along the interface.The anchoring force of CRPB balances the coal-rock slip and suppresses crack formation,resulting in a more cohesive response under dynamic load.展开更多
Background:Human skin is affected by ultraviolet rays on a daily basis,and excessive ultraviolet radiation(UVR)can lead to sunburn erythema,tanning,photoaging,and skin tumors.The combination of Astragali Radix(AR)and ...Background:Human skin is affected by ultraviolet rays on a daily basis,and excessive ultraviolet radiation(UVR)can lead to sunburn erythema,tanning,photoaging,and skin tumors.The combination of Astragali Radix(AR)and Anemarrhenae Rhizoma(AAR)is a common pairing in traditional Chinese medicine(TCM).According to earlier studies,they possess properties capable of alleviating the adverse impacts of UVR on the skin.However,the specific actions and underlying mechanisms require further investigation.The study aims to analyze the efficacy of AR-AAR in preventing UVR-induced skin damage and to clarify the associated molecular mechanisms.Methods:Potential signaling pathways by which AR and AAR may protect against UVR-induced skin damage were identified with network pharmacology,molecular docking techniques and molecular dynamics(MD)simulation.Except the normal group,the back skin of SD rats was exposed to 1.1 mW/cm^(2) UVA combined with 0.1 mW/cm^(2) UVB daily,and the UVR skin damage model was established.Morphological features of skin tissues of different groups were discovered through Hematoxylin and Eosin(HE)staining,Masson staining,Weigert staining.ELISA was utilized to measure the levels of reactive oxygen species(ROS),Interleukin 6(IL-6),Interleukin 1β(IL-1β)and Tumor necrosis factos-α(TNF-α)in skin tissues.RT-PCR and Western blot were employed to quantify the mRNA and protein contents of PI3K,AKT,and MMP-9.Results:Network pharmacology analysis predicts that AR-AAR may improve skin damage induced by UVR through the PI3K/AKT signaling pathway.Histological staining shows that AR-AAR can significantly reduce inflammatory infiltration and fibrosis in damaged skin.Treatment with AR-AAR(2:1)significantly reduced the expression levels of IL-1β,IL-6,TNF-αand ROS in UVR-damaged rat skin.After treatment with AR-AAR(2:1),not only did the relative mRNA expression levels of PI3K and AKT and the protein expression levels of PI3K,AKT,P-PI3K,and P-AKT increase,but the mRNA and protein expression levels of MMP-9 decreased.Conclusion:The study indicate that the AR-AAR combination and its active components may mitigate UVR skin damage by modulating the PI3K/AKT signaling pathway.展开更多
Polyfluoroalkyl substances(PFAS)have emerged as persistent environmental contaminants because of their chemical stability,degradation-resistance and bioaccumulation potential.However,current studies mainly focus on th...Polyfluoroalkyl substances(PFAS)have emerged as persistent environmental contaminants because of their chemical stability,degradation-resistance and bioaccumulation potential.However,current studies mainly focus on the toxicity of single PFAS such as perfluorooctanoic acid(PFOA)and perfluorobutanoic acid(PFBA),the knowledge of their combined effects is relatively limited.In this study,we explored the immune response of the gut in large yellow croaker(Larimichthys crocea)under the combined stress of PFOA and PFBA.Histologicalanalyses revealed that the combined effect induced intestinal vacuolization and decreased the length of intestinal villi.And it significantly activated pro-inflammatory pathways with marked upregulation of tnfα,il1β,il6 and myd88 expressions,particularly after 14 days of exposure.Gut microbiota analysis revealed substantial dysbiosis,including 1)reduced alpha diversity,2)increased abundance of potential pathogenic taxa(Proteobacteria and Spirochaetota),and 3)depletion of beneficial Firmicutes.PICRUSt-based functional prediction indicated temporal metabolic shifts,with upregulation of DNA repair pathways at day 3 and enhanced bacterial motility protein activity at days 7 and 14 of post-exposure.The Pearson correlation analysis further indicated that these immune genes had significant positive correlations with Vibrio and Brevinema,and negative correlations with Streptococcus.Our present study will provide novel insights into the microbiome-mediated immunomodulation in the larger yellow croaker exposed to combined PFAS,which will be helpful for healthy farming of economically important marine species.展开更多
Constructing nanofibers with specific therapeutic effects against cancer is a challenge.Here,we present the synthesis approach and application prospects of supramolecular nanofibers,which are based on cucurbit[8]uril(...Constructing nanofibers with specific therapeutic effects against cancer is a challenge.Here,we present the synthesis approach and application prospects of supramolecular nanofibers,which are based on cucurbit[8]uril(CB[8])as the host and terpyridine lanthanum ions metal complex as the vip,constructed by layer-by-layer self-assembly through supramolecular interaction.Moreover,nanofibers with lanthanide luminescence properties exhibit surprising pH-responsive deformation properties and antibacterial behavior.In the tumor micro-environment,the dramatic reduction in the size of the nanofibers enables specific and hierarchical release of anticancer drugs in tumor cells to exert an advanced therapeutic effect.In addition,the synergistic therapeutic efficacy was achieved by reducing the excess of Gram-positive and Gram-negative bacteria surrounding tumor cells.The novel supramolecular nanofibers with sequential drug release and combined therapeutic mode provide new guidance for the synthesis of drug carrier materials and direction for the promotion of nanomaterial-mediated cancer therapy.展开更多
We develop an ultrafast Yb-fiber laser system based on eight-channel coherent beam combining utilizing commercially available rod-type Yb-fibers.To ensure good combining efficiency and long-term operation of the syste...We develop an ultrafast Yb-fiber laser system based on eight-channel coherent beam combining utilizing commercially available rod-type Yb-fibers.To ensure good combining efficiency and long-term operation of the system at the attosecond laser facility under construction,we fully stabilize the phase,group-delay,and beam-pointing of the eight fiber channels.Especially,we propose a novel multi-step hill climbing method to control both group-delay and beam-pointing.At a repetition rate of 1 MHz,this laser system delivers 270-fs pulses with 1.18-k W average power(1.18-m J pulse energy).The average-power instability of the laser system running for 12 hours is 0.32%.展开更多
The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To...The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To develop an efficient flow field reconstruction model for this,we present an Improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN),which integrates Conditional Denoising Diffusion Probabilistic Models(CDDPMs)with Style GAN,and introduce a reconstruction discrimination mechanism and dynamic loss weight learning strategy.We establish the Mach number flow field dataset by numerical simulation at various backpressures for the mode transition process from turbine mode to ejector ramjet mode at Mach number 2.5.The proposed ICDDGAN model,given only sparse parameter information,can rapidly generate high-quality Mach number flow fields without a large number of samples for training.The results show that ICDDGAN is superior to CDDGAN in terms of training convergence and stability.Moreover,the interpolation and extrapolation test results during backpressure conditions show that ICDDGAN can accurately and quickly reconstruct Mach number fields at various tunnel slice shapes,with a Structural Similarity Index Measure(SSIM)of over 0.96 and a Mean-Square Error(MSE)of 0.035%to actual flow fields,reducing time costs by 7-8 orders of magnitude compared to Computational Fluid Dynamics(CFD)calculations.This can provide an efficient means for rapid computation of complex flow fields.展开更多
Objective:To observe the efficacy of acupuncture combined with traditional Chinese herbs in the treatment of poststroke vascular dementia(VD)and the effects on serum interleukin(IL)-6 and superoxide dismutase(SOD).Met...Objective:To observe the efficacy of acupuncture combined with traditional Chinese herbs in the treatment of poststroke vascular dementia(VD)and the effects on serum interleukin(IL)-6 and superoxide dismutase(SOD).Methods:A total of 240 patients with poststroke VD were selected and randomly divided into two groups according to the random number table method,with 120 cases in each group.Both groups received Hua Tan Tong Luo(phlegmresolving and collateral-activating)formula,once daily;the observation group was additionally treated with Yi Shen Tiao Du(kidney-tonifying and Governor Vessel-regulating)acupuncture once daily for 6 consecutive days,followed by 1 d of rest.Both groups were treated for 15 d as one course,for a total of 2 courses.After treatment,the total effective rate was compared.Changes in scores of traditional Chinese medicine(TCM)symptoms,clinical dementia rating(CDR),National Institutes of Health stroke scale(NIHSS),and Chinese version of mini-mental state examination(MMSE),and serum levels of IL-6 and SOD were observed in both groups.Results:The total effective rate in the observation group was higher than that in the control group(P<0.05).After treatment,TCM symptom,CDR,and NIHSS scores,and serum IL-6 levels in both groups were lower than those before treatment(P<0.05),while MMSE scores and serum SOD levels were higher than those before treatment(P<0.05).After treatment,the observation group showed lower TCM symptom,CDR,and NIHSS scores,and serum IL-6 levels than the control group(P<0.05),and higher MMSE scores and serum SOD levels than the control group(P<0.05).Conclusion:Compared to Hua Tan Tong Luo formula alone,Yi Shen Tiao Du acupuncture combined with Hua Tan Tong Luo formula demonstrates better efficacy in reducing dementia severity,improving cognitive and neurological function,and inhibiting inflammation in patients with poststroke VD.展开更多
The existence of the"stomach-knee axis"and the potential independent association between"Helicobacter pylori(Hp)infection and knee osteoarthritis(KOA)"have been substantiated through multiple lines...The existence of the"stomach-knee axis"and the potential independent association between"Helicobacter pylori(Hp)infection and knee osteoarthritis(KOA)"have been substantiated through multiple lines of evidence,including epidemiological studies of the"stomach-knee axis",investigations into the pathological mechanisms linking"Hp infection and arthritis",as well as research on co-treatment drugs and the anti-inflammatory mechanisms relevant to"gastritis and arthritis".The investigation into"stomach and knee joint treatment"is grounded in the concept that the"stomach-knee axis"aligns with the"combined bi of body constituents and zang organs"theory.Clinical cases have demonstrated that therapeutic strategies of"stomach and knee joint treatment"can mitigate KOA damage by modulating the"stomach-knee axis"and eradicating Hp infection in the stomach.This study aims to contribute novel insights into the cross-system treatment of KOA.Further investigation into the"stomach-knee axis"may yield innovative strategies for the prevention and management of KOA,potentially through the eradication of Hp.展开更多
Objective To observe the influence of different acupoint combinations on immediate effect of surface electromyography of patients with cervical spondylosis, and to explore the interactions and laws among different acu...Objective To observe the influence of different acupoint combinations on immediate effect of surface electromyography of patients with cervical spondylosis, and to explore the interactions and laws among different acupoint combinations. Methods Acupuncture in three kinds of different acupoint combinations was conducted on 90 patients with cervical spondylosis（three groups）： group A [distal point selection group： Kūnlún（昆仑 BL 60） and Hòuxī（后溪 SI 3）]; group B [local point selection group： Fēngchí（风池 GB 20） and Tiānzhù（天柱 BL 10）]; group C（distal and local point selection group： BL 60, SI 3, GB 20 and BL 10）. Self control before and after treatment was adopted to observe the mean value of surface electromyography（SEMG） amplitude, to measure the mean values of integrated electromyography（IEMG） and electromyography root mean square（RMS）, and to calculate the variation rate of electromyography amplitude of trapezius on the affected side of patients before and after acupuncture. The differences of influences of different acupoint combinations on immediate effect of surface electromyography were compared intra-group, and the differences among the three groups after acupuncture were also compared. Results According to the intragroup comparison before and after acupuncture, the differences of mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS were both statistically significant（all P〈0.05）. According to the inter-group comparison after acupuncture, the mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS varied in different degrees, however, the differences were not significant（all P〉0.05）; there was no significant difference in the total effective rate among the three groups（P〉0.05）. Conclusion Acupuncture treatment in different acupoint combinations can increase IEMG and RMS and reduce mean value of electromyography amplitude and variation rate of electromyography amplitude, enhance cervical vertebral stability and active contractility of muscle fiber, and improve the fatigue resistance of neck flexion; while, the therapeutic effect of acupuncture on cervical spondylosis has nothing to do with the distance or the number of selected acupoint.展开更多
During 2000-2013, totally ten high-amylose specific hybrid rice combinations approved and five combinations for production test were bred in Sichuan Province. In the paper, rice yield, economic traits, quality indicat...During 2000-2013, totally ten high-amylose specific hybrid rice combinations approved and five combinations for production test were bred in Sichuan Province. In the paper, rice yield, economic traits, quality indicators and rice blast-resistance identification results of these 15 hybrid combinations were described and analyzed. Results show that Chuanxiangyou37 and Tianlongyou540 have relatively high amylose content, good yielding ability, high resistance and appropriate growth period, which are new hybrid rice varieties with organic combination of high amylase content, high gel consistency, high yield, stable yield and wide adaptability. Therefore, Chuanxiangyou37 and Tianlongyou540 are recommended as the main combination for rice production.展开更多
Programmed cell death 1（PD-1）/programmed cell death 1 ligand（PD-L1） blockade has shown promising effects in cancer immunotherapy. Removing the so-called ＂brakes＂ on T cell immune responses by blocking the PD-1/P...Programmed cell death 1（PD-1）/programmed cell death 1 ligand（PD-L1） blockade has shown promising effects in cancer immunotherapy. Removing the so-called ＂brakes＂ on T cell immune responses by blocking the PD-1/PDL1 check point should boost anti-tumor immunity and provide durable tumor regression for cancer patients.However, 30%–60% of patients show no response to PD-1/PD-L1 blockade. Thus, it is urgent to explore the underlying resistance mechanisms to improve sensitivity to anti-PD-1/PD-L1 therapy. We propose that the mechanisms promoting resistance mainly include T cell exclusion or exhaustion at the tumor site,immunosuppressive factors in the tumor microenvironment（TME）, and a range of tumor-intrinsic factors. This review highlights the power of studying the cellular and molecular mechanisms of resistance to improve the rational design of combination therapeutic strategies that can be translated to the clinic. Here, we briefly discuss the development of PD-1/PD-L1 blockade agents and focus on the current issues and future prospects for potential combinatorial therapeutic strategies that include anti-PD-1/PD-L1 therapy, based upon the available preclinical and clinical data.展开更多
Tackling the problems of underground water storage in collieries in arid regions requires knowledge of the effect of water intrusion and loading rate on the mechanical properties of and crack development in coal–rock...Tackling the problems of underground water storage in collieries in arid regions requires knowledge of the effect of water intrusion and loading rate on the mechanical properties of and crack development in coal–rock combinations. Fifty-four coal–rock combinations were prepared and split equally into groups containing different moisture contents(dry, natural moisture and saturated) to conduct acoustic emission testing under uniaxial compression with loading rates ranging from 0.1 mm/min to 0.6 mm/min. The results show that the peak stress and strength-softening modulus, elastic modulus, strain-softening modulus, and post-peak modulus partly decrease with increasing moisture content and loading rate. In contrast, peak strain increases with increasing moisture content and fluctuates with rising loading rate. More significantly, the relationship between stiffness and stress, combined with accumulated counts of acoustic emission, can be used to precisely predict all phases of crack propagation. This is helpful in studying the impact of moisture content and loading rate on crack propagation and accurately calculating mechanical properties. We also determined that the stress thresholds of crack closure, crack initiation, and crack damage do not vary with changes of moisture content and loading rate, constituting 15.22%, 32.20%, and 80.98% of peak stress, respectively. These outcomes assist in developing approaches to water storage in coal mines, determining the necessary width of waterproof coal–rock pillars, and methods of supporting water-enriched roadways, while also advances understanding the mechanical properties of coal–rock combinations and laws of crack propagation.展开更多
Given the extensive utilization of cantilever retaining walls in construction and development projects,their optimal design and analysis with proper attention to seismic loads is a typical engineering problem.This res...Given the extensive utilization of cantilever retaining walls in construction and development projects,their optimal design and analysis with proper attention to seismic loads is a typical engineering problem.This research presents a new algorithm for pseudo-static analysis of retaining walls employing upper bound method.The algorithm can be utilized to design and check the external and internal stability of the wall based on the proposed mechanism.One of the main features of this algorithm is its ability to determine the critical condition of failure wedges,the minimum safety factor and maximum force acting on the wall,as well as the minimum weight of the wall,simultaneously,by effectively using the multi-objective optimization.The results obtained by the proposed failure mechanisms show that,while using the upper bound limit analysis approach,the active force should be maximized concurrent with optimizing the direction of the plane passing through the back of the heel.The present study also applies the proposed algorithm to determine the critical direction of the earthquake acceleration coefficient.The critical direction of earthquake acceleration coefficient is defined as the direction that maximizes the active force exerted on the wall and minimizes the safety factor for wall stability.The results obtained in this study are in good agreement with those of similar studies carried out based on the limit equilibrium method and finite element analysis.The critical failure mechanisms were determined via optimization with genetic algorithm.展开更多
traditional In this paper, two drawbacks pseudo-static method （vertical of the slice method） in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to...traditional In this paper, two drawbacks pseudo-static method （vertical of the slice method） in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to this method, which is irrational to some extent in the seismic design of slope. Second, only peak ground acceleration （PGA） is considered, and the effects of shaking frequency and duration on slope stability are neglected. And then, based on the theory of elastic wave and the summarized geological model, this paper put forwards an improved method of pseudo-method by using the theory of elastic wave and Hilbert-Huang transform. The improved pseudostatic method gives reasonable considerations to the time-frequency effects of seismic wave and its rationality has been verified by the shaking table test. This method can evaluate the safety of a slope, the happening time and the scale of landslides. At the same time, this method also can improve the high accuracy of the evaluation of the safety of the slope.展开更多
Many researchers have developed new calculation methods to analyze seismic slope stability problems, but the conventional pseudo-static method is still widely used in engineering design due to its simplicity. Based on...Many researchers have developed new calculation methods to analyze seismic slope stability problems, but the conventional pseudo-static method is still widely used in engineering design due to its simplicity. Based on the Technical Code for Building Slope Engineering（GB 50330-2013） of China and the Guidelines for Evaluating and Mitigating Seismic Hazards in California（SP117）, a comparative study on the pseudo-static method was performed. The results indicate that the largest difference between these two design codes lies in determination of the seismic equivalence reduction factor( f;). The GB 50330-2013 code specifies a single value for f;of 0.25. In SP117, numerous factors,such as magnitude and distance, are considered in determining f;. Two case studies show that the types of slope stability status evaluated by SP117 are in agreement with those evaluated by the seismic time-history stability analysis and Newmark displacement analysis. The factors of safety evaluated by SP117 can be used in practice for safe design. However, the factors of safety evaluated by GB 50330-2013 are risky for slope seismic design.展开更多
This paper describes a commonly used pseudo-static method in seismic resistant design of the cross section of underground structures. Based on dynamic theory and the vibration characteristics of underground structures...This paper describes a commonly used pseudo-static method in seismic resistant design of the cross section of underground structures. Based on dynamic theory and the vibration characteristics of underground structures, the sources of errors when using this method are analyzed. The traditional seismic motion loading approach is replaced by a method in which a one-dimensional soil layer response stress is differentiated and then converted into seismic live loads. To validate the improved method, a comparison of analytical results is conducted for internal forces under earthquake shaking of a typical shallow embedded box-shaped subway station structure using four methods： the response displacement method, finite element response acceleration method, the finite element dynamic analysis method and the improved pseudo-static calculation method. It is shown that the improved finite element pseudo-static method proposed in this paper provides an effective tool for the seismic design of underground structures. The evaluation yields results close to those obtained by the finite element dynamic analysis method, and shows that the improved finite element pseudo-static method provides a higher degree of precision.展开更多
基金supported by the National Natural Science Foundation(32130068,32271634,and 32071597)CAS Key Laboratory of Forest Ecology and Silviculture,Institute of Applied Ecology,Chinese Academy of Sciences(KLFES-2025)。
文摘Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species.
基金supported by grants from the Chinese Academy of Sciences(XDA24010101)the Biological Breeding-National Science and Technology Major Project(2024ZD04077)+2 种基金the National Key Research and Development Program of China(2023YFF1001200)Natural Science Foundation of Zhejiang Province(LD24C130001)the Agricultural Science and Technology Innovation Program(ASTIP)of CAAS。
文摘A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that regulates heading date,plant height and grain number.Here,we investigated the relationship between Ghd7 and florigen genes Hd3a and RFT1,to determine their roles in regulating heading date and grain number under different photoperiods.Our results revealed that under long-day(LD)conditions,Hd3a acts prior to RFT1 to promote heading while negatively regulating plant height and grain number.In contrast,Ghd7 positively regulates heading date,plant height,and grain number by inhibiting both Hd3a and RFT1.Under short-day(SD)conditions,the functions of Hd3a and RFT1 remain consistent with those under LD conditions,but Ghd7 does not inhibit their expression,resulting in a weaker phenotypic effect compared to Hd3a.Additionally,under both LD and SD conditions,increased Ghd7 expression enhances its inhibitory effect on Hd3a and RFT1,leading to later heading and increased grain number;however,once the heading date exceeds 94 d,grain number no longer increases.Moreover,the gn1a allele increased grain number by 16.5%to 42.5%,while combinations of the elite alleles from Ghd7,Hd3a,RFT1,and Gn1a significantly increased grain number by up to 240.9%.Therefore,we propose a new breeding strategy to optimize the heading date and grain number using the Ghd7Hd3aRFT1gn1a combination of Ghd7,Hd3a,RFT1,and Gn1a under LD conditions,and the Ghd7hd3aRFT1gn1a combination under SD conditions.This strategy improved the yield of the high-quality Northeast variety Kongyu 131(KY131)by 69.1%in Beijing and 93.7%in Hainan.This strategy will greatly improve the efficiency of north-to-south adaptation in rice,providing theoretical guidance for expanding the geographical adaptability of rice varieties.
基金supported by National Science Foundations of China(Grant No.11771340,12171373).
文摘Recently,Choe-Koo-Wang(J Funct Anal,2020,278)demonstrated the rigid phenomenon:The compact linear combination of composition operators under the Coefficient Non-cancellation Condition(CNC),implies that each difference is compact on the weighted Bergman space in the unit disk.Motivated by the subtle connection of composition operator theory on the weighted Bergman spaces,Korenblum spaces and bounded holomorphic function spaces,we first explore the rigid phenomenon which also holds on the Korenblum space over the unit ball.Furthermore,we discuss which difference of composition operators is compact when the compact combination of composition operators does not satisfy the condition(CNC)on Korenblum spaces and bounded holomorphic function spaces over the unit ball setting.
基金supported by the National Natural Science Foundation of China(No.52274026)the National Key Research and Development Program(No.2022YFC2806504)the CNOOC Research Project(No.KJGG-2022-17-04 and NO.KJGG-2022-17-05).
文摘Effective isolation between the cement sheath and the sandstone is crucial for the development and production of oil and gas wells in sandstone formations.In this study,a cement-sandstone composite(CSC)was prepared,and based onμ-CT three-dimensional reconstruction imaging and finite element analysis(FEA)techniques,the stress distribution and potential failure mechanism at the cement-sandstone bonding interface under axial loading were analyzed.The key findings are as follows:(1)stress concentrations are highly likely to form at the gap between the cement and sandstone interface and around interfacial voids,with Von Mises stress reaching critical levels of 18.0-20.0 MPa at these locations,significantly exceeding the stress magnitudes in well-bonded regions;(2)the phenomenon of local stress concentration driven by interfacial defects can be identified as the main basis for predicting damage location in interfacial debonding and continuous shear under axial load;(3)ensuring tight cementation at the cement-sandstone interface and minimizing interfacial voids are paramount for preventing stress-induced failure;(4)the critical Von Mises stress value of 20 MPa at the interface defect can be used as a benchmark for material selection and designed to ensure long-term integrity in oil and gas well applications subjected to similar axial loads.These findings contribute to a more accurate understanding of the failure mechanism of the cement-sandstone interface and to the precise design of material properties,thereby ensuring the long-term integrity of oil and gas well applications subjected to similar axial loads.
基金Financial support from the National Natural Science Foundation of China(Grant No.52374119)the Province Education Department of Liaoning(Grant No.LJ212410146068)the opening fund of State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure,East China Jiaotong University(Grant No.HJGZ2023103).
文摘Understanding the mechanical properties of coal-rock-bolt(CRB)combinations at high strain rates and the anchoring mechanism of bolts is crucial for ensuring the safety of coal mining operations.However,the dynamic behaviors of these combinations,especially the mechanism of action of prestressed bolts,still need to be further investigated.This study carried out split Hopkinson pressure bar(SHPB)tests on three sets of coal-rock(CR),CRB,and coal-rock-prestressed bolt(CRPB)combinations with different interface angles(β=15°,30°,45°,and 60°).The dynamic properties of the combinations were analyzed based on the stress-strain curve,energy dissipation,dynamic strength,fractal dimension of cracks,and failure mode of bolts.The test results show that a larger β will affect the stress transfer and anti-sliding ability of CR,resulting in a decrease in CR strength.The anchoring force of the bolt effectively suppresses the slip feature of CRB at the yield stage.As the strain rate increases,CRB shows a more pronounced'sudden increase'in strength,and the bolt significantly enhances its dynamic strength.The prestressed bolts enhance the dynamic strength of CRPB while weaken the effect of β.The fractal dimension of the macrocracks increases with strain rate,with smaller variations in CRB and CRPB,indicating that the bolt reduces the complexity degree of CRB and CRPB.The anchoring force of CRB depends on bolt strength,which reduces the slip along the interface.The anchoring force of CRPB balances the coal-rock slip and suppresses crack formation,resulting in a more cohesive response under dynamic load.
基金supported by the Shaanxi Qinchuang Yuan“scientist+engineer”team construction(No.2023KXJ-080)Shaanxi Chiral Drug Engineering Technology Research Center(Department of Science and Technology of Shaanxi Province.No.[2011]-251).
文摘Background:Human skin is affected by ultraviolet rays on a daily basis,and excessive ultraviolet radiation(UVR)can lead to sunburn erythema,tanning,photoaging,and skin tumors.The combination of Astragali Radix(AR)and Anemarrhenae Rhizoma(AAR)is a common pairing in traditional Chinese medicine(TCM).According to earlier studies,they possess properties capable of alleviating the adverse impacts of UVR on the skin.However,the specific actions and underlying mechanisms require further investigation.The study aims to analyze the efficacy of AR-AAR in preventing UVR-induced skin damage and to clarify the associated molecular mechanisms.Methods:Potential signaling pathways by which AR and AAR may protect against UVR-induced skin damage were identified with network pharmacology,molecular docking techniques and molecular dynamics(MD)simulation.Except the normal group,the back skin of SD rats was exposed to 1.1 mW/cm^(2) UVA combined with 0.1 mW/cm^(2) UVB daily,and the UVR skin damage model was established.Morphological features of skin tissues of different groups were discovered through Hematoxylin and Eosin(HE)staining,Masson staining,Weigert staining.ELISA was utilized to measure the levels of reactive oxygen species(ROS),Interleukin 6(IL-6),Interleukin 1β(IL-1β)and Tumor necrosis factos-α(TNF-α)in skin tissues.RT-PCR and Western blot were employed to quantify the mRNA and protein contents of PI3K,AKT,and MMP-9.Results:Network pharmacology analysis predicts that AR-AAR may improve skin damage induced by UVR through the PI3K/AKT signaling pathway.Histological staining shows that AR-AAR can significantly reduce inflammatory infiltration and fibrosis in damaged skin.Treatment with AR-AAR(2:1)significantly reduced the expression levels of IL-1β,IL-6,TNF-αand ROS in UVR-damaged rat skin.After treatment with AR-AAR(2:1),not only did the relative mRNA expression levels of PI3K and AKT and the protein expression levels of PI3K,AKT,P-PI3K,and P-AKT increase,but the mRNA and protein expression levels of MMP-9 decreased.Conclusion:The study indicate that the AR-AAR combination and its active components may mitigate UVR skin damage by modulating the PI3K/AKT signaling pathway.
基金supported by the Ningbo Natural Science Foundation(Youth Foundation,No.2024J449)the Scientific Research Foundation for Introduced Talents of Ningbo University(Nos.ZX2022000602 and ZX2024000043)。
文摘Polyfluoroalkyl substances(PFAS)have emerged as persistent environmental contaminants because of their chemical stability,degradation-resistance and bioaccumulation potential.However,current studies mainly focus on the toxicity of single PFAS such as perfluorooctanoic acid(PFOA)and perfluorobutanoic acid(PFBA),the knowledge of their combined effects is relatively limited.In this study,we explored the immune response of the gut in large yellow croaker(Larimichthys crocea)under the combined stress of PFOA and PFBA.Histologicalanalyses revealed that the combined effect induced intestinal vacuolization and decreased the length of intestinal villi.And it significantly activated pro-inflammatory pathways with marked upregulation of tnfα,il1β,il6 and myd88 expressions,particularly after 14 days of exposure.Gut microbiota analysis revealed substantial dysbiosis,including 1)reduced alpha diversity,2)increased abundance of potential pathogenic taxa(Proteobacteria and Spirochaetota),and 3)depletion of beneficial Firmicutes.PICRUSt-based functional prediction indicated temporal metabolic shifts,with upregulation of DNA repair pathways at day 3 and enhanced bacterial motility protein activity at days 7 and 14 of post-exposure.The Pearson correlation analysis further indicated that these immune genes had significant positive correlations with Vibrio and Brevinema,and negative correlations with Streptococcus.Our present study will provide novel insights into the microbiome-mediated immunomodulation in the larger yellow croaker exposed to combined PFAS,which will be helpful for healthy farming of economically important marine species.
基金supported by the National Natural Science Foundation of China(No.82273919)Natural Science Foundation of Heilongjiang Province(No.LH2024H013)China Postdoctoral Science Foundation(No.2022MD723781).
文摘Constructing nanofibers with specific therapeutic effects against cancer is a challenge.Here,we present the synthesis approach and application prospects of supramolecular nanofibers,which are based on cucurbit[8]uril(CB[8])as the host and terpyridine lanthanum ions metal complex as the vip,constructed by layer-by-layer self-assembly through supramolecular interaction.Moreover,nanofibers with lanthanide luminescence properties exhibit surprising pH-responsive deformation properties and antibacterial behavior.In the tumor micro-environment,the dramatic reduction in the size of the nanofibers enables specific and hierarchical release of anticancer drugs in tumor cells to exert an advanced therapeutic effect.In addition,the synergistic therapeutic efficacy was achieved by reducing the excess of Gram-positive and Gram-negative bacteria surrounding tumor cells.The novel supramolecular nanofibers with sequential drug release and combined therapeutic mode provide new guidance for the synthesis of drug carrier materials and direction for the promotion of nanomaterial-mediated cancer therapy.
基金Project supported by the Key Deployment Special Research Project of the Chinese Academy of Sciences(Grant No.PTYQ2022YZ0001)the National Natural Science Foundation of China(Grant Nos.62175255 and 62227822)the National Key Research and Development Program of China(Grant No.2021YFB3602602)。
文摘We develop an ultrafast Yb-fiber laser system based on eight-channel coherent beam combining utilizing commercially available rod-type Yb-fibers.To ensure good combining efficiency and long-term operation of the system at the attosecond laser facility under construction,we fully stabilize the phase,group-delay,and beam-pointing of the eight fiber channels.Especially,we propose a novel multi-step hill climbing method to control both group-delay and beam-pointing.At a repetition rate of 1 MHz,this laser system delivers 270-fs pulses with 1.18-k W average power(1.18-m J pulse energy).The average-power instability of the laser system running for 12 hours is 0.32%.
文摘The internal flow fields within a three-dimensional inward-tunning combined inlet are extremely complex,especially during the engine mode transition,where the tunnel changes may impact the flow fields significantly.To develop an efficient flow field reconstruction model for this,we present an Improved Conditional Denoising Diffusion Generative Adversarial Network(ICDDGAN),which integrates Conditional Denoising Diffusion Probabilistic Models(CDDPMs)with Style GAN,and introduce a reconstruction discrimination mechanism and dynamic loss weight learning strategy.We establish the Mach number flow field dataset by numerical simulation at various backpressures for the mode transition process from turbine mode to ejector ramjet mode at Mach number 2.5.The proposed ICDDGAN model,given only sparse parameter information,can rapidly generate high-quality Mach number flow fields without a large number of samples for training.The results show that ICDDGAN is superior to CDDGAN in terms of training convergence and stability.Moreover,the interpolation and extrapolation test results during backpressure conditions show that ICDDGAN can accurately and quickly reconstruct Mach number fields at various tunnel slice shapes,with a Structural Similarity Index Measure(SSIM)of over 0.96 and a Mean-Square Error(MSE)of 0.035%to actual flow fields,reducing time costs by 7-8 orders of magnitude compared to Computational Fluid Dynamics(CFD)calculations.This can provide an efficient means for rapid computation of complex flow fields.
基金supported by the Research Cultivation Project of Beijing Municipal Hospital(北京市属医院科研培育课题,No.PZ2022015).
文摘Objective:To observe the efficacy of acupuncture combined with traditional Chinese herbs in the treatment of poststroke vascular dementia(VD)and the effects on serum interleukin(IL)-6 and superoxide dismutase(SOD).Methods:A total of 240 patients with poststroke VD were selected and randomly divided into two groups according to the random number table method,with 120 cases in each group.Both groups received Hua Tan Tong Luo(phlegmresolving and collateral-activating)formula,once daily;the observation group was additionally treated with Yi Shen Tiao Du(kidney-tonifying and Governor Vessel-regulating)acupuncture once daily for 6 consecutive days,followed by 1 d of rest.Both groups were treated for 15 d as one course,for a total of 2 courses.After treatment,the total effective rate was compared.Changes in scores of traditional Chinese medicine(TCM)symptoms,clinical dementia rating(CDR),National Institutes of Health stroke scale(NIHSS),and Chinese version of mini-mental state examination(MMSE),and serum levels of IL-6 and SOD were observed in both groups.Results:The total effective rate in the observation group was higher than that in the control group(P<0.05).After treatment,TCM symptom,CDR,and NIHSS scores,and serum IL-6 levels in both groups were lower than those before treatment(P<0.05),while MMSE scores and serum SOD levels were higher than those before treatment(P<0.05).After treatment,the observation group showed lower TCM symptom,CDR,and NIHSS scores,and serum IL-6 levels than the control group(P<0.05),and higher MMSE scores and serum SOD levels than the control group(P<0.05).Conclusion:Compared to Hua Tan Tong Luo formula alone,Yi Shen Tiao Du acupuncture combined with Hua Tan Tong Luo formula demonstrates better efficacy in reducing dementia severity,improving cognitive and neurological function,and inhibiting inflammation in patients with poststroke VD.
基金Supported by Discipline Construction Project of Shanxi University of Chinese Medicine—Internal Medicine of Traditional Chinese Medicine(2025XK02).
文摘The existence of the"stomach-knee axis"and the potential independent association between"Helicobacter pylori(Hp)infection and knee osteoarthritis(KOA)"have been substantiated through multiple lines of evidence,including epidemiological studies of the"stomach-knee axis",investigations into the pathological mechanisms linking"Hp infection and arthritis",as well as research on co-treatment drugs and the anti-inflammatory mechanisms relevant to"gastritis and arthritis".The investigation into"stomach and knee joint treatment"is grounded in the concept that the"stomach-knee axis"aligns with the"combined bi of body constituents and zang organs"theory.Clinical cases have demonstrated that therapeutic strategies of"stomach and knee joint treatment"can mitigate KOA damage by modulating the"stomach-knee axis"and eradicating Hp infection in the stomach.This study aims to contribute novel insights into the cross-system treatment of KOA.Further investigation into the"stomach-knee axis"may yield innovative strategies for the prevention and management of KOA,potentially through the eradication of Hp.
基金Supported by “The 12th five-year plan” programmed project of educational science in Hubei Province:2014B095
文摘Objective To observe the influence of different acupoint combinations on immediate effect of surface electromyography of patients with cervical spondylosis, and to explore the interactions and laws among different acupoint combinations. Methods Acupuncture in three kinds of different acupoint combinations was conducted on 90 patients with cervical spondylosis（three groups）： group A [distal point selection group： Kūnlún（昆仑 BL 60） and Hòuxī（后溪 SI 3）]; group B [local point selection group： Fēngchí（风池 GB 20） and Tiānzhù（天柱 BL 10）]; group C（distal and local point selection group： BL 60, SI 3, GB 20 and BL 10）. Self control before and after treatment was adopted to observe the mean value of surface electromyography（SEMG） amplitude, to measure the mean values of integrated electromyography（IEMG） and electromyography root mean square（RMS）, and to calculate the variation rate of electromyography amplitude of trapezius on the affected side of patients before and after acupuncture. The differences of influences of different acupoint combinations on immediate effect of surface electromyography were compared intra-group, and the differences among the three groups after acupuncture were also compared. Results According to the intragroup comparison before and after acupuncture, the differences of mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS were both statistically significant（all P〈0.05）. According to the inter-group comparison after acupuncture, the mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS varied in different degrees, however, the differences were not significant（all P〉0.05）; there was no significant difference in the total effective rate among the three groups（P〉0.05）. Conclusion Acupuncture treatment in different acupoint combinations can increase IEMG and RMS and reduce mean value of electromyography amplitude and variation rate of electromyography amplitude, enhance cervical vertebral stability and active contractility of muscle fiber, and improve the fatigue resistance of neck flexion; while, the therapeutic effect of acupuncture on cervical spondylosis has nothing to do with the distance or the number of selected acupoint.
基金Supported by Financial Genetic Engineering Program of Sichuan Province during the 12th Five-Year Plan Period(2011JYGC11-029)Sichuan Innovation Team Program of National Modern Agricultural Industry Technology System of China+1 种基金Rice Breeding Program of Sichuan Province during the 12th Five-Year Plan Period(2011NZ-0098-1)Major Scientific and Technological Project of Luzhou City(2011-N-09)~~
文摘During 2000-2013, totally ten high-amylose specific hybrid rice combinations approved and five combinations for production test were bred in Sichuan Province. In the paper, rice yield, economic traits, quality indicators and rice blast-resistance identification results of these 15 hybrid combinations were described and analyzed. Results show that Chuanxiangyou37 and Tianlongyou540 have relatively high amylose content, good yielding ability, high resistance and appropriate growth period, which are new hybrid rice varieties with organic combination of high amylase content, high gel consistency, high yield, stable yield and wide adaptability. Therefore, Chuanxiangyou37 and Tianlongyou540 are recommended as the main combination for rice production.
基金supported by grants from the National Natural Science Foundation of China (No. 81171986)the Ministry of Public Health (No. 201501004)
文摘Programmed cell death 1（PD-1）/programmed cell death 1 ligand（PD-L1） blockade has shown promising effects in cancer immunotherapy. Removing the so-called ＂brakes＂ on T cell immune responses by blocking the PD-1/PDL1 check point should boost anti-tumor immunity and provide durable tumor regression for cancer patients.However, 30%–60% of patients show no response to PD-1/PD-L1 blockade. Thus, it is urgent to explore the underlying resistance mechanisms to improve sensitivity to anti-PD-1/PD-L1 therapy. We propose that the mechanisms promoting resistance mainly include T cell exclusion or exhaustion at the tumor site,immunosuppressive factors in the tumor microenvironment（TME）, and a range of tumor-intrinsic factors. This review highlights the power of studying the cellular and molecular mechanisms of resistance to improve the rational design of combination therapeutic strategies that can be translated to the clinic. Here, we briefly discuss the development of PD-1/PD-L1 blockade agents and focus on the current issues and future prospects for potential combinatorial therapeutic strategies that include anti-PD-1/PD-L1 therapy, based upon the available preclinical and clinical data.
基金Project(2014QNB31)supported by the Fundamental Research Funds for the Central Universities,ChinaProjects(51674248)supported by the National Natural Science Foundation of ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘Tackling the problems of underground water storage in collieries in arid regions requires knowledge of the effect of water intrusion and loading rate on the mechanical properties of and crack development in coal–rock combinations. Fifty-four coal–rock combinations were prepared and split equally into groups containing different moisture contents(dry, natural moisture and saturated) to conduct acoustic emission testing under uniaxial compression with loading rates ranging from 0.1 mm/min to 0.6 mm/min. The results show that the peak stress and strength-softening modulus, elastic modulus, strain-softening modulus, and post-peak modulus partly decrease with increasing moisture content and loading rate. In contrast, peak strain increases with increasing moisture content and fluctuates with rising loading rate. More significantly, the relationship between stiffness and stress, combined with accumulated counts of acoustic emission, can be used to precisely predict all phases of crack propagation. This is helpful in studying the impact of moisture content and loading rate on crack propagation and accurately calculating mechanical properties. We also determined that the stress thresholds of crack closure, crack initiation, and crack damage do not vary with changes of moisture content and loading rate, constituting 15.22%, 32.20%, and 80.98% of peak stress, respectively. These outcomes assist in developing approaches to water storage in coal mines, determining the necessary width of waterproof coal–rock pillars, and methods of supporting water-enriched roadways, while also advances understanding the mechanical properties of coal–rock combinations and laws of crack propagation.
文摘Given the extensive utilization of cantilever retaining walls in construction and development projects,their optimal design and analysis with proper attention to seismic loads is a typical engineering problem.This research presents a new algorithm for pseudo-static analysis of retaining walls employing upper bound method.The algorithm can be utilized to design and check the external and internal stability of the wall based on the proposed mechanism.One of the main features of this algorithm is its ability to determine the critical condition of failure wedges,the minimum safety factor and maximum force acting on the wall,as well as the minimum weight of the wall,simultaneously,by effectively using the multi-objective optimization.The results obtained by the proposed failure mechanisms show that,while using the upper bound limit analysis approach,the active force should be maximized concurrent with optimizing the direction of the plane passing through the back of the heel.The present study also applies the proposed algorithm to determine the critical direction of the earthquake acceleration coefficient.The critical direction of earthquake acceleration coefficient is defined as the direction that maximizes the active force exerted on the wall and minimizes the safety factor for wall stability.The results obtained in this study are in good agreement with those of similar studies carried out based on the limit equilibrium method and finite element analysis.The critical failure mechanisms were determined via optimization with genetic algorithm.
基金supported in part by National Science Foundation of China (Contract NO. 41030742)Guangxi Science Foundation and the Program for Science & Technology of Henan Province in China (Grant No. 142300410200)
文摘traditional In this paper, two drawbacks pseudo-static method （vertical of the slice method） in the slope stability evaluation have been studied. First, the sliding mass is divided into vertical slices according to this method, which is irrational to some extent in the seismic design of slope. Second, only peak ground acceleration （PGA） is considered, and the effects of shaking frequency and duration on slope stability are neglected. And then, based on the theory of elastic wave and the summarized geological model, this paper put forwards an improved method of pseudo-method by using the theory of elastic wave and Hilbert-Huang transform. The improved pseudostatic method gives reasonable considerations to the time-frequency effects of seismic wave and its rationality has been verified by the shaking table test. This method can evaluate the safety of a slope, the happening time and the scale of landslides. At the same time, this method also can improve the high accuracy of the evaluation of the safety of the slope.
基金supported by the National Key R&D Program of China(Grant No.2017YFC0404804)the National Natural Science Foundation of China(Grant No.51509019)
文摘Many researchers have developed new calculation methods to analyze seismic slope stability problems, but the conventional pseudo-static method is still widely used in engineering design due to its simplicity. Based on the Technical Code for Building Slope Engineering（GB 50330-2013） of China and the Guidelines for Evaluating and Mitigating Seismic Hazards in California（SP117）, a comparative study on the pseudo-static method was performed. The results indicate that the largest difference between these two design codes lies in determination of the seismic equivalence reduction factor( f;). The GB 50330-2013 code specifies a single value for f;of 0.25. In SP117, numerous factors,such as magnitude and distance, are considered in determining f;. Two case studies show that the types of slope stability status evaluated by SP117 are in agreement with those evaluated by the seismic time-history stability analysis and Newmark displacement analysis. The factors of safety evaluated by SP117 can be used in practice for safe design. However, the factors of safety evaluated by GB 50330-2013 are risky for slope seismic design.
基金China Earthquake Administration Association Fund Under Grant No. 106060 and Institute of Engineering Mechanics Director Fund
文摘This paper describes a commonly used pseudo-static method in seismic resistant design of the cross section of underground structures. Based on dynamic theory and the vibration characteristics of underground structures, the sources of errors when using this method are analyzed. The traditional seismic motion loading approach is replaced by a method in which a one-dimensional soil layer response stress is differentiated and then converted into seismic live loads. To validate the improved method, a comparison of analytical results is conducted for internal forces under earthquake shaking of a typical shallow embedded box-shaped subway station structure using four methods： the response displacement method, finite element response acceleration method, the finite element dynamic analysis method and the improved pseudo-static calculation method. It is shown that the improved finite element pseudo-static method proposed in this paper provides an effective tool for the seismic design of underground structures. The evaluation yields results close to those obtained by the finite element dynamic analysis method, and shows that the improved finite element pseudo-static method provides a higher degree of precision.
