AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the...AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the retinal tissue in diabetic rats.METHODS:The expression of HDAC7 in HRMECs under high glucose and the retinal tissue from normal or diabetic rats were detected with immunohistochemistry and Western blot.LV-shHDAC7 HRMECs were used to study the effect of HDAC7 on cell activities.Cell count kit-8(CCK-8),5-ethynyl2’-deoxyuridine(EdU),flow cytometry,scratch test,Transwell test and tube formation assay were used to examine the ability of cell proliferation,migration,and angiogenesis.Finally,a preliminary exploration of its mechanism was performed by Western blot.RESULTS:The expression of HDAC7 was both upregulated in retinal tissues of diabetic rats and high glucosetreated HRMECs.Down-regulation of HDAC7 expression significantly reduced the ability of proliferation,migration,and tube formation,and reversed the high glucose-induced high expression of CDK1/Cyclin B1 and vascular endothelial growth factor in high glucose-treated HRMECs.CONCLUSION:High glucose can up-regulate the expression of HDAC7 in HRMECs.Down-regulation of HDAC7 can inhibit HRMECs activities.HDAC7 is proposed to be involved in pathogenesis of diabetic retinopathy and a therapeutic target.展开更多
In recent years,paper-based functional materials have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure and good flexibility.As an impo...In recent years,paper-based functional materials have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure and good flexibility.As an important energy storage device,paper-based supercapacitors have important application prospects in many fields and have also received extensive attention from researchers in recent years.At present,researchers have modified and regulated paper-based materials by different means such as structural design and material composition to enhance their electrochemical storage capacity.The development of paper-based supercapacitors provides an important direction for the development of green and sustainable energy.Therefore,it is of great significance to summarize the relevant work of paper-based supercapacitors for their rapid development and application.In this review,the recent research progress of paper-based supercapacitors based on cellulose was summarized in terms of various cellulose-based composites,preparation skills,and electrochemical performance.Finally,some opinions on the problems in the development of this field and the future development trend were proposed.It is hoped that this review can provide valuable references and ideas for the rapid development of paper-based energy storage devices.展开更多
BACKGROUND This study investigated the construction and clinical validation of a predictive model for neuroaggression in patients with gastric cancer.Gastric cancer is one of the most common malignant tumors in the wo...BACKGROUND This study investigated the construction and clinical validation of a predictive model for neuroaggression in patients with gastric cancer.Gastric cancer is one of the most common malignant tumors in the world,and neuroinvasion is the key factor affecting the prognosis of patients.However,there is a lack of systematic analysis on the construction and clinical application of its prediction model.This study adopted a single-center retrospective study method,collected a large amo-unt of clinical data,and applied statistics and machine learning technology to build and verify an effective prediction model for neuroaggression,with a view to providing scientific basis for clinical treatment decisions and improving the tr-eatment effect and survival rate of patients with gastric cancer.AIM To investigate the value of a model based on clinical data,spectral computed to-mography(CT)parameters and image omics characteristics for the preoperative prediction of nerve invasion in patients with gastric cancer.METHODS A retrospective analysis was performed on 80 gastric cancer patients who under-went preoperative energy spectrum CT at our hospital between January 2022 and August 2023,these patients were divided into a positive group and a negative group according to their pathological results.Clinicopathological data were collected,the energy spectrum parameters of primary gastric cancer lesions were measured,and single factor analysis was performed.A total of 214 image omics features were extracted from two-phase mixed energy images,and the features were screened by single factor analysis and a support vector machine.The variables with statist-ically significant differences were included in logistic regression analysis to construct a prediction model,and the performance of the model was evaluated using the subject working characteristic curve.There were statistically significant differences in sex,carbohydrate antigen 199 expression,tumor thickness,Lauren classification and Borrmann classification between the two groups(all P<0.05).Among the energy spectrum parameters,there were statistically significant differences in the single energy values(CT60-CT110 keV)at the arterial stage between the two groups(all P<0.05)and statistically significant differences in CT values,iodide group values,standardized iodide group values and single energy values except CT80 keV at the portal vein stage between the two groups(all P<0.05).The support vector machine model with the largest area under the curve was selected by image omics analysis,and its area under the curve,sensitivity,specificity,accuracy,P value and pa-rameters were 0.843,0.923,0.714,0.925,<0.001,and c:g 2.64:10.56,respectively.Finally,based on the logistic regression algorithm,a clinical model,an energy spectrum CT model,an imaging model,a clinical+energy spe-ctrum model,a clinical+imaging model,an energy spectrum+imaging model,and a clinical+energy spectrum+imaging model were established,among which the clinical+energy spectrum+imaging model had the best efficacy in diagnosing gastric cancer nerve invasion.The area under the curve,optimal threshold,Youden index,sensitivity and specificity were 0.927(95%CI:0.850-1.000),0.879,0.778,0.778,and 1.000,respectively.CONCLUSION The combined model based on clinical features,spectral CT parameters and imaging data has good value for the preoperative prediction of gastric cancer neuroinvasion.展开更多
Mg alloy casting parts commonly suffer from drawbacks of low surface properties,high susceptibility to corrosion,unsatisfactory absolute strength,and poor ductility,which seriously limit their wide application.Here,a ...Mg alloy casting parts commonly suffer from drawbacks of low surface properties,high susceptibility to corrosion,unsatisfactory absolute strength,and poor ductility,which seriously limit their wide application.Here,a surface nanocrystallization technique,i.e.,ultrasonic surface rolling(USR),was applied on an as-cast AZ91 Mg alloy sheet to improve its corrosion resistance and mechanical properties.The USR produces double smooth surfaces with Ra 0.036μm and gradient nanostructured surface layers on the sheet.Due to this special microstructure modification,the USR sheet exhibits 55%and 50%improvements in yield strength and ultimate tensile strength without visibly sacrificed ductility comparable to its untreated counterpart,as well as a 24%improvement in surface hardness.The USR sheet also shows good corrosion resistance in 3.5wt%NaCl aqueous solution.The corrosion current density of the USR sheet reduces by 63%after immersion for 1 h,and 25%after immersion for 24 h compared to that of the untreated counterpart.The enhanced strength and hardness are mainly related to the gradient nanostructure.The improved corrosion resistance is mainly ascribed to the decreased surface roughness,nanostructured surface,and residual compressive stress.The present results state that USR is an effective and attractive method to improve the multiple properties of Mg alloy cast-ing parts,and thus can be used as an additional and last working procedure to achieve high-performance Mg alloy casting parts.展开更多
Although a various of existing techniques are able to improve the performance of detection of the weak interesting sig- nal, how to adaptively and efficiently attenuate the intricate noises especially in the case of n...Although a various of existing techniques are able to improve the performance of detection of the weak interesting sig- nal, how to adaptively and efficiently attenuate the intricate noises especially in the case of no available reference noise signal is still the bottleneck to be overcome. According to the characteristics of sonar arrays, a multi-channel differencing method is presented to provide the prerequisite reference noise. However, the ingre- dient of obtained reference noise is too complicated to be used to effectively reduce the interference noise only using the clas- sical linear cancellation methods. Hence, a novel adaptive noise cancellation method based on the multi-kernel normalized least- mean-square algorithm consisting of weighted linear and Gaussian kernel functions is proposed, which allows to simultaneously con- sider the cancellation of linear and nonlinear components in the reference noise. The simulation results demonstrate that the out- put signal-to-noise ratio (SNR) of the novel multi-kernel adaptive filtering method outperforms the conventional linear normalized least-mean-square method and the mono-kernel normalized least- mean-square method using the realistic noise data measured in the lake experiment.展开更多
Most metals including Mg alloys have a longstanding dilemma of strength-ductility trade-off,which is hindering their wider applications.In this study,we propose a gradient heterogeneous grain(GHG)structure for evading...Most metals including Mg alloys have a longstanding dilemma of strength-ductility trade-off,which is hindering their wider applications.In this study,we propose a gradient heterogeneous grain(GHG)structure for evading this trade-off dilemma and ultrasonic severe surface rolling is attempted to construct this novel structure in ZE41 Mg alloy.Here,the GHG structure combine the benefits of gradient structure and heterogeneous grain structure and introduce large microstructural heterogeneities.Compared to the coarse-grain and heterogeneous-grain structured alloys,the GHG structured one exhibits dramatical enhancement in strength,ductility,and strain hardening capability.To the best of our knowledge,its strength becomes much higher than that of common ZE41 Mg alloys at no reduction in ductility.These unique mechanical properties stem from not only the individual contribution of the heterogeneous structure components including the fine/ultrafine grains and deformed coarse grains but also their synergistic effect via hetero-deformation induced strengthening and hardening effects.In summary,our study provides a feasible way to develop new Mg alloys with high strength and good ductility.展开更多
Background:Melatonin,a natural hormone secreted by the pineal gland,has been reported to exhibit antitumor properties through diverse mechanisms of action.However,the oncostatic function of melatonin on esophageal squ...Background:Melatonin,a natural hormone secreted by the pineal gland,has been reported to exhibit antitumor properties through diverse mechanisms of action.However,the oncostatic function of melatonin on esophageal squamous cell carcinoma(ESCC) remains elusive.This study was conducted to investigate the potential effect and underlying molecular mechanism of melatonin as single anticancer agent against ESCC cells.Methods:ESCC cell lines treated with or without melatonin were used in this study.In vitro colony formation and 5-Ethynyl-2’-deoxyuridine(EdU) incorporation assays,and nude mice tumor xenograft model were used to confirm the proliferative capacities of ESCC cells.RNA-seq,qPCR,Western blotting,recombinant lentivirus-mediated target gene overexpression or knockdown,plasmids transfection and co-IP were applied to investigate the underlying molecular mechanism by which melatonin inhibited ESCC cell growth.IHC staining on ESCC tissue microarray and further survival analyses were performed to explore the relationship between target genes’ expression and prognosis of ESCC.Results:Melatonin treatment dose-dependently inhibited the proliferative ability and the expression of histone deacetylase 7(HDAC7),c-Myc and ubiquitin-specific peptidase 10(USP10) in ESCC cells(P<0.05).The expressions of HDAC7,c-Myc and USP10 in tumors were significantly higher than the paired normal tissues from 148 ESCC patients(P<0.001).Then,the Kaplan-Meier survival analysis suggested that ESCC patients with high HDAC7,c-Myc or USP10levels predicted worse overall survival(log-rank P<0.001).Co-IP and Western blotting further revealed that HDAC7physically deacetylated and activated β-catenin thus promoting downstream target c-Myc gene transcription.Notably,our mechanistic study validated that HDAC7/β-catenin/c-Myc could form the positive feedback loop to enhance ESCC cell growth,and USP10 could deubiquitinate and stabilize HDAC7 protein in the ESCC cells.Additionally,we verified that inhibition of the HDAC7/β-catenin/c-Myc axis and USP10/HDAC7 pathway mediated the anti-proliferative action of melatonin on ESCC cells.Conclusions:Our findings elucidate that melatonin mitigates the HDAC7/β-catenin/c-Myc positive feedback loop and inhibits the USP10-maintained HDAC7 protein stability thus suppressing ESCC cell growth,and provides the reference for identifying biomarkers and therapeutic targets for ESCC.展开更多
Carbon dots(CDs)are a fascinating new class of fluorescent nanomaterials,yet the understanding of the fluorescent origin of CDs still lags well behind their applications.The key challenges for unveiling the fluorescen...Carbon dots(CDs)are a fascinating new class of fluorescent nanomaterials,yet the understanding of the fluorescent origin of CDs still lags well behind their applications.The key challenges for unveiling the fluorescent mechanism of CDs relate to the insufficient basis for structural evaluation.This work presents a temperature-gradient route to control the bottom-up approach of CDs,enabling the precise structural characterization of intermediates and the establishment of definite structure-property relationships,akin to the domino reaction synthesis of complex natural products from small organic molecules.Taking the binary components citric acid and meta-dimethylaminophenol generated CDs as a case study,their emissive mechanism,particularly the unique excitation-dependent fluorescence behavior,is reasonably explained and supported by structural evaluation through retrosynthetic analysis.The formation process of CDs is investigated using a combination of spectroscopic,thermal,and theoretical calculation techniques,demonstrating the significant potential of the temperature-gradient route in the exploration structure-property relationships and guiding the rational design of advanced CD applications.展开更多
Summary What is already known about this topic?Approximately 50%of patients with mpox are human immunodeficiency virus(HIV)-infected globally.Studies have shown that individuals with advanced HIV infection tend to hav...Summary What is already known about this topic?Approximately 50%of patients with mpox are human immunodeficiency virus(HIV)-infected globally.Studies have shown that individuals with advanced HIV infection tend to have more severe clinical manifestations and higher mortality rates after mpox infection.What is added by this report?展开更多
In complex strata, oil-based drilling fluid is the preferred drilling fluid system, but its preparation cost is high, and there are hidden safety risks. Therefore, the new progress of high-performance anti-collapse wa...In complex strata, oil-based drilling fluid is the preferred drilling fluid system, but its preparation cost is high, and there are hidden safety risks. Therefore, the new progress of high-performance anti-collapse water-based drilling fluid at home and abroad is analyzed. It is difficult to prevent and control the well collapse. Once the well wall instability problem occurs, it will often bring huge economic losses to the enterprises, and the underground safety accidents will occur. In order to ensure the stability of the well wall and improve the downhole safety, the key treatment agent of water-based collapse drilling fluid is selected, the anti-collapse drilling fluid system is formulated, the evaluation method of drilling fluid prevention performance is established, and a set of water-based drilling fluid system suitable for easy to collapse strata in China is selected to ensure the downhole safety. The development trend of high performance anti-collapse water-based drilling fluid is expected to provide a reference for the research of high performance anti-collapse water-based drilling fluid system and key treatment agent.展开更多
This project is explaining a laboratory development of a solid free drilling fluid formula that could be potentially used in tight gas reservoirs. The configuration of the weak gel fluid WGL-1, which is resistant to h...This project is explaining a laboratory development of a solid free drilling fluid formula that could be potentially used in tight gas reservoirs. The configuration of the weak gel fluid WGL-1, which is resistant to high temperature and high salt, was tested, and concluded that its gelling properties, salt and temperature resistance, and environmental protection were all in line with industry requirements. The final drilling fluid formula was developed as: water + (0.3% ~ 0.5%) NaOH + 5% KCl + 2% WGL-1 + 5% NaCl + (1.0% ~ 2.0%) HBFR Anti-high temperature fluid loss agent + 2% Polyol + (1.5% ~ 2.0%) SDL-1 Lubricant + 0.4% A4O1. The performance of the liquid was tested for temperature resistance, inhibition, gas formation protection effect, plugging performance, and static settlement stability. It was concluded that the temperature resistance performance is satisfied at 150°C, and the cuttings recovery rate is as high as 96.78%. It has good performance in inhibiting water dispersion and swelling of cuttings. The permeability recovery value reaches 88.9%, which meets the requirements of gas formation protection. The SSSI value shows that its settlement stability is good;under high temperature and high pressure, its sealing performance is good. This drilling fluid system has achieved the expected results and laid a foundation for further promoting the development of solid-free drilling fluid systems. The future development direction of solid-free drilling fluids is pointed out, to the improvement of properties to be applied in high temperature environment and have high salt resistance capacity.展开更多
In this paper, we explore the process of emotional state transition. And the process is impacted by emotional state of interaction objects. First of all, the cognitive reasoning process and the micro-expressions recog...In this paper, we explore the process of emotional state transition. And the process is impacted by emotional state of interaction objects. First of all, the cognitive reasoning process and the micro-expressions recognition is the basis of affective computing adjustment process. Secondly, the threshold function and attenuation function are proposed to quantify the emotional changes. In the actual environment, the emotional state of the robot and external stimulus are also quantified as the transferring probability. Finally, the Gaussian cloud distribution is introduced to the Gross model to calculate the emotional transitional probabilities. The experimental results show that the model in human-computer interaction can effectively regulate the emotional states, and can significantly improve the humanoid and intelligent ability of the robot. This model is consistent with experimental and emulational significance of the psychology, and allows the robot to get rid of the mechanical emotional transfer process.展开更多
Salidroside,the main active ingredient extracted from Rhodiola crenulata,has been shown to be neuroprotective in ischemic cerebral injury,but the underlying mechanism for this neuroprotection is poorly understood.In t...Salidroside,the main active ingredient extracted from Rhodiola crenulata,has been shown to be neuroprotective in ischemic cerebral injury,but the underlying mechanism for this neuroprotection is poorly understood.In the current study,the neuroprotective effect of salidroside on cerebral ischemia-induced oxidative stress and the role of the nuclear factor erythroid 2-related factor 2(Nrf2)pathway was investigated in a rat model of middle cerebral artery occlusion.Salidroside(30 mg/kg)reduced infarct size,improved neurological function and histological changes,increased activity of superoxide dismutase and glutathione-S-transferase,and reduced malon-dialdehyde levels after cerebral ischemia and reperfusion.Furthermore,salidroside apparently increased Nrf2 and heme oxygenase-1 expression.These results suggest that salidroside exerts its neuroprotective effect against cerebral ischemia through anti-oxidant mechanisms and that activation of the Nrf2 pathway is involved.The Nrf2/antioxidant response element pathway may become a new therapeutic target for the treatment of ischemic stroke.展开更多
Recovery following stroke involves neurogenesis and axonal remodeling within the ischemic brain. Gualou Guizhi decoction (GLGZD) is a Chinese traditional medicine used for the treatment of post-stroke limb spasm. GL...Recovery following stroke involves neurogenesis and axonal remodeling within the ischemic brain. Gualou Guizhi decoction (GLGZD) is a Chinese traditional medicine used for the treatment of post-stroke limb spasm. GLGZD has been reported to have neuroprotective effects in cerebral ischemic injury. However, the effects of GLGZD on neurogenesis and axonal remodeling following cerebral ischemia remain unknown. In this study, a rat model of focal cerebral ischemia/reperfusion was established by middle cerebral artery occlusion. Neurologi- cal function was assessed immediately after reperfusion using Longa's 5-point scoring system. The rats were randomly divided into vehicle and GLGZD groups. Rats in the sham group were given sham operation. The rats in the GLGZD group were intragastrically administered GLGZD, once daily, for 14 consecutive days. The rats in the vehicle and sham groups were intragastrically administered distilled water. Modified neurological severity score test, balance beam test and foot fault test were used to assess motor functional changes. Nissl staining was performed to evaluate histopathological changes in the brain. Immunofluorescence staining was used to examine cell proliferation using the marker 5-bromo-2'-deoxyuridine (BrdU) as well as expression of the neural precursor marker doublecortin (DCX), the astrocyte marker glial fibrillary acidic protein (GFAP) and the axon regeneration marker growth associated protein-43 (GAP-43). GLGZD substan- tially mitigated pathological injury, increased the number of BrdU, DCX and GFAP-immunoreactive cells in the subventricular zone of the ischemic hemisphere, increased GAP-43 expression in the cortical peri-infarct region, and improved motor function. These findings suggest that GLGZD promotes neurological functional recovery by increasing cell proliferation, enhancing axonal regeneration, and in- creasing the numbers of neuronal precursors and astrocytes in the peri-infarct area.展开更多
基金Supported by the Shaanxi Province Traditional Chinese Medicine Project(No.SZY-KJCYC-2023-028)。
文摘AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the retinal tissue in diabetic rats.METHODS:The expression of HDAC7 in HRMECs under high glucose and the retinal tissue from normal or diabetic rats were detected with immunohistochemistry and Western blot.LV-shHDAC7 HRMECs were used to study the effect of HDAC7 on cell activities.Cell count kit-8(CCK-8),5-ethynyl2’-deoxyuridine(EdU),flow cytometry,scratch test,Transwell test and tube formation assay were used to examine the ability of cell proliferation,migration,and angiogenesis.Finally,a preliminary exploration of its mechanism was performed by Western blot.RESULTS:The expression of HDAC7 was both upregulated in retinal tissues of diabetic rats and high glucosetreated HRMECs.Down-regulation of HDAC7 expression significantly reduced the ability of proliferation,migration,and tube formation,and reversed the high glucose-induced high expression of CDK1/Cyclin B1 and vascular endothelial growth factor in high glucose-treated HRMECs.CONCLUSION:High glucose can up-regulate the expression of HDAC7 in HRMECs.Down-regulation of HDAC7 can inhibit HRMECs activities.HDAC7 is proposed to be involved in pathogenesis of diabetic retinopathy and a therapeutic target.
基金supported by the fund of the National Natural Science Foundation of China(22078184,22171170)the China Postdoctoral Science Foundation(2019M653853XB)+1 种基金the Natural Science Advance Research Foundation of Shaanxi University of Science and Technology(2018QNBJ-03)Major Scientific and Technological Innovation Projects in Shandong Province(2019TSLH0316)
文摘In recent years,paper-based functional materials have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure and good flexibility.As an important energy storage device,paper-based supercapacitors have important application prospects in many fields and have also received extensive attention from researchers in recent years.At present,researchers have modified and regulated paper-based materials by different means such as structural design and material composition to enhance their electrochemical storage capacity.The development of paper-based supercapacitors provides an important direction for the development of green and sustainable energy.Therefore,it is of great significance to summarize the relevant work of paper-based supercapacitors for their rapid development and application.In this review,the recent research progress of paper-based supercapacitors based on cellulose was summarized in terms of various cellulose-based composites,preparation skills,and electrochemical performance.Finally,some opinions on the problems in the development of this field and the future development trend were proposed.It is hoped that this review can provide valuable references and ideas for the rapid development of paper-based energy storage devices.
文摘BACKGROUND This study investigated the construction and clinical validation of a predictive model for neuroaggression in patients with gastric cancer.Gastric cancer is one of the most common malignant tumors in the world,and neuroinvasion is the key factor affecting the prognosis of patients.However,there is a lack of systematic analysis on the construction and clinical application of its prediction model.This study adopted a single-center retrospective study method,collected a large amo-unt of clinical data,and applied statistics and machine learning technology to build and verify an effective prediction model for neuroaggression,with a view to providing scientific basis for clinical treatment decisions and improving the tr-eatment effect and survival rate of patients with gastric cancer.AIM To investigate the value of a model based on clinical data,spectral computed to-mography(CT)parameters and image omics characteristics for the preoperative prediction of nerve invasion in patients with gastric cancer.METHODS A retrospective analysis was performed on 80 gastric cancer patients who under-went preoperative energy spectrum CT at our hospital between January 2022 and August 2023,these patients were divided into a positive group and a negative group according to their pathological results.Clinicopathological data were collected,the energy spectrum parameters of primary gastric cancer lesions were measured,and single factor analysis was performed.A total of 214 image omics features were extracted from two-phase mixed energy images,and the features were screened by single factor analysis and a support vector machine.The variables with statist-ically significant differences were included in logistic regression analysis to construct a prediction model,and the performance of the model was evaluated using the subject working characteristic curve.There were statistically significant differences in sex,carbohydrate antigen 199 expression,tumor thickness,Lauren classification and Borrmann classification between the two groups(all P<0.05).Among the energy spectrum parameters,there were statistically significant differences in the single energy values(CT60-CT110 keV)at the arterial stage between the two groups(all P<0.05)and statistically significant differences in CT values,iodide group values,standardized iodide group values and single energy values except CT80 keV at the portal vein stage between the two groups(all P<0.05).The support vector machine model with the largest area under the curve was selected by image omics analysis,and its area under the curve,sensitivity,specificity,accuracy,P value and pa-rameters were 0.843,0.923,0.714,0.925,<0.001,and c:g 2.64:10.56,respectively.Finally,based on the logistic regression algorithm,a clinical model,an energy spectrum CT model,an imaging model,a clinical+energy spe-ctrum model,a clinical+imaging model,an energy spectrum+imaging model,and a clinical+energy spectrum+imaging model were established,among which the clinical+energy spectrum+imaging model had the best efficacy in diagnosing gastric cancer nerve invasion.The area under the curve,optimal threshold,Youden index,sensitivity and specificity were 0.927(95%CI:0.850-1.000),0.879,0.778,0.778,and 1.000,respectively.CONCLUSION The combined model based on clinical features,spectral CT parameters and imaging data has good value for the preoperative prediction of gastric cancer neuroinvasion.
基金This work was financially supported by the National Natural Science Foundation of China(No.U1910212)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Mg alloy casting parts commonly suffer from drawbacks of low surface properties,high susceptibility to corrosion,unsatisfactory absolute strength,and poor ductility,which seriously limit their wide application.Here,a surface nanocrystallization technique,i.e.,ultrasonic surface rolling(USR),was applied on an as-cast AZ91 Mg alloy sheet to improve its corrosion resistance and mechanical properties.The USR produces double smooth surfaces with Ra 0.036μm and gradient nanostructured surface layers on the sheet.Due to this special microstructure modification,the USR sheet exhibits 55%and 50%improvements in yield strength and ultimate tensile strength without visibly sacrificed ductility comparable to its untreated counterpart,as well as a 24%improvement in surface hardness.The USR sheet also shows good corrosion resistance in 3.5wt%NaCl aqueous solution.The corrosion current density of the USR sheet reduces by 63%after immersion for 1 h,and 25%after immersion for 24 h compared to that of the untreated counterpart.The enhanced strength and hardness are mainly related to the gradient nanostructure.The improved corrosion resistance is mainly ascribed to the decreased surface roughness,nanostructured surface,and residual compressive stress.The present results state that USR is an effective and attractive method to improve the multiple properties of Mg alloy cast-ing parts,and thus can be used as an additional and last working procedure to achieve high-performance Mg alloy casting parts.
基金supported by the National Natural Science Foundation of China(6100115361271415)+2 种基金the Opening Research Foundation of State Key Laboratory of Underwater Information Processing and Control(9140C231002130C23085)the Fundamental Research Funds for the Central Universities(3102014JCQ010103102014ZD0041)
文摘Although a various of existing techniques are able to improve the performance of detection of the weak interesting sig- nal, how to adaptively and efficiently attenuate the intricate noises especially in the case of no available reference noise signal is still the bottleneck to be overcome. According to the characteristics of sonar arrays, a multi-channel differencing method is presented to provide the prerequisite reference noise. However, the ingre- dient of obtained reference noise is too complicated to be used to effectively reduce the interference noise only using the clas- sical linear cancellation methods. Hence, a novel adaptive noise cancellation method based on the multi-kernel normalized least- mean-square algorithm consisting of weighted linear and Gaussian kernel functions is proposed, which allows to simultaneously con- sider the cancellation of linear and nonlinear components in the reference noise. The simulation results demonstrate that the out- put signal-to-noise ratio (SNR) of the novel multi-kernel adaptive filtering method outperforms the conventional linear normalized least-mean-square method and the mono-kernel normalized least- mean-square method using the realistic noise data measured in the lake experiment.
基金the financial support of the National Natural Science Foundation of China(Grant No.51971088,No.U1910212)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Most metals including Mg alloys have a longstanding dilemma of strength-ductility trade-off,which is hindering their wider applications.In this study,we propose a gradient heterogeneous grain(GHG)structure for evading this trade-off dilemma and ultrasonic severe surface rolling is attempted to construct this novel structure in ZE41 Mg alloy.Here,the GHG structure combine the benefits of gradient structure and heterogeneous grain structure and introduce large microstructural heterogeneities.Compared to the coarse-grain and heterogeneous-grain structured alloys,the GHG structured one exhibits dramatical enhancement in strength,ductility,and strain hardening capability.To the best of our knowledge,its strength becomes much higher than that of common ZE41 Mg alloys at no reduction in ductility.These unique mechanical properties stem from not only the individual contribution of the heterogeneous structure components including the fine/ultrafine grains and deformed coarse grains but also their synergistic effect via hetero-deformation induced strengthening and hardening effects.In summary,our study provides a feasible way to develop new Mg alloys with high strength and good ductility.
基金supported by the National Natural Science Foundation of China (82103508, 81871866, 82173252, 81672996)the Natural Science Foundation of Shaanxi Province (2022JQ?862)。
文摘Background:Melatonin,a natural hormone secreted by the pineal gland,has been reported to exhibit antitumor properties through diverse mechanisms of action.However,the oncostatic function of melatonin on esophageal squamous cell carcinoma(ESCC) remains elusive.This study was conducted to investigate the potential effect and underlying molecular mechanism of melatonin as single anticancer agent against ESCC cells.Methods:ESCC cell lines treated with or without melatonin were used in this study.In vitro colony formation and 5-Ethynyl-2’-deoxyuridine(EdU) incorporation assays,and nude mice tumor xenograft model were used to confirm the proliferative capacities of ESCC cells.RNA-seq,qPCR,Western blotting,recombinant lentivirus-mediated target gene overexpression or knockdown,plasmids transfection and co-IP were applied to investigate the underlying molecular mechanism by which melatonin inhibited ESCC cell growth.IHC staining on ESCC tissue microarray and further survival analyses were performed to explore the relationship between target genes’ expression and prognosis of ESCC.Results:Melatonin treatment dose-dependently inhibited the proliferative ability and the expression of histone deacetylase 7(HDAC7),c-Myc and ubiquitin-specific peptidase 10(USP10) in ESCC cells(P<0.05).The expressions of HDAC7,c-Myc and USP10 in tumors were significantly higher than the paired normal tissues from 148 ESCC patients(P<0.001).Then,the Kaplan-Meier survival analysis suggested that ESCC patients with high HDAC7,c-Myc or USP10levels predicted worse overall survival(log-rank P<0.001).Co-IP and Western blotting further revealed that HDAC7physically deacetylated and activated β-catenin thus promoting downstream target c-Myc gene transcription.Notably,our mechanistic study validated that HDAC7/β-catenin/c-Myc could form the positive feedback loop to enhance ESCC cell growth,and USP10 could deubiquitinate and stabilize HDAC7 protein in the ESCC cells.Additionally,we verified that inhibition of the HDAC7/β-catenin/c-Myc axis and USP10/HDAC7 pathway mediated the anti-proliferative action of melatonin on ESCC cells.Conclusions:Our findings elucidate that melatonin mitigates the HDAC7/β-catenin/c-Myc positive feedback loop and inhibits the USP10-maintained HDAC7 protein stability thus suppressing ESCC cell growth,and provides the reference for identifying biomarkers and therapeutic targets for ESCC.
基金supported by the National Natural Science Foundation of China(21875060 and 22076042).
文摘Carbon dots(CDs)are a fascinating new class of fluorescent nanomaterials,yet the understanding of the fluorescent origin of CDs still lags well behind their applications.The key challenges for unveiling the fluorescent mechanism of CDs relate to the insufficient basis for structural evaluation.This work presents a temperature-gradient route to control the bottom-up approach of CDs,enabling the precise structural characterization of intermediates and the establishment of definite structure-property relationships,akin to the domino reaction synthesis of complex natural products from small organic molecules.Taking the binary components citric acid and meta-dimethylaminophenol generated CDs as a case study,their emissive mechanism,particularly the unique excitation-dependent fluorescence behavior,is reasonably explained and supported by structural evaluation through retrosynthetic analysis.The formation process of CDs is investigated using a combination of spectroscopic,thermal,and theoretical calculation techniques,demonstrating the significant potential of the temperature-gradient route in the exploration structure-property relationships and guiding the rational design of advanced CD applications.
基金Provided by the National Natural Science Foundation of the People’s Republic of China(Grant No.71934002)the Beijing Hospitals Authority(Grant No.XMLX202149).
文摘Summary What is already known about this topic?Approximately 50%of patients with mpox are human immunodeficiency virus(HIV)-infected globally.Studies have shown that individuals with advanced HIV infection tend to have more severe clinical manifestations and higher mortality rates after mpox infection.What is added by this report?
文摘In complex strata, oil-based drilling fluid is the preferred drilling fluid system, but its preparation cost is high, and there are hidden safety risks. Therefore, the new progress of high-performance anti-collapse water-based drilling fluid at home and abroad is analyzed. It is difficult to prevent and control the well collapse. Once the well wall instability problem occurs, it will often bring huge economic losses to the enterprises, and the underground safety accidents will occur. In order to ensure the stability of the well wall and improve the downhole safety, the key treatment agent of water-based collapse drilling fluid is selected, the anti-collapse drilling fluid system is formulated, the evaluation method of drilling fluid prevention performance is established, and a set of water-based drilling fluid system suitable for easy to collapse strata in China is selected to ensure the downhole safety. The development trend of high performance anti-collapse water-based drilling fluid is expected to provide a reference for the research of high performance anti-collapse water-based drilling fluid system and key treatment agent.
文摘This project is explaining a laboratory development of a solid free drilling fluid formula that could be potentially used in tight gas reservoirs. The configuration of the weak gel fluid WGL-1, which is resistant to high temperature and high salt, was tested, and concluded that its gelling properties, salt and temperature resistance, and environmental protection were all in line with industry requirements. The final drilling fluid formula was developed as: water + (0.3% ~ 0.5%) NaOH + 5% KCl + 2% WGL-1 + 5% NaCl + (1.0% ~ 2.0%) HBFR Anti-high temperature fluid loss agent + 2% Polyol + (1.5% ~ 2.0%) SDL-1 Lubricant + 0.4% A4O1. The performance of the liquid was tested for temperature resistance, inhibition, gas formation protection effect, plugging performance, and static settlement stability. It was concluded that the temperature resistance performance is satisfied at 150°C, and the cuttings recovery rate is as high as 96.78%. It has good performance in inhibiting water dispersion and swelling of cuttings. The permeability recovery value reaches 88.9%, which meets the requirements of gas formation protection. The SSSI value shows that its settlement stability is good;under high temperature and high pressure, its sealing performance is good. This drilling fluid system has achieved the expected results and laid a foundation for further promoting the development of solid-free drilling fluid systems. The future development direction of solid-free drilling fluids is pointed out, to the improvement of properties to be applied in high temperature environment and have high salt resistance capacity.
文摘In this paper, we explore the process of emotional state transition. And the process is impacted by emotional state of interaction objects. First of all, the cognitive reasoning process and the micro-expressions recognition is the basis of affective computing adjustment process. Secondly, the threshold function and attenuation function are proposed to quantify the emotional changes. In the actual environment, the emotional state of the robot and external stimulus are also quantified as the transferring probability. Finally, the Gaussian cloud distribution is introduced to the Gross model to calculate the emotional transitional probabilities. The experimental results show that the model in human-computer interaction can effectively regulate the emotional states, and can significantly improve the humanoid and intelligent ability of the robot. This model is consistent with experimental and emulational significance of the psychology, and allows the robot to get rid of the mechanical emotional transfer process.
基金supported by the Independent Research Project of Fujian Academy of Traditional Chinese Medicine in China,No.2012fjzyyk-4the Natural Science Foundation of Fujian Province in China,No.2014J01340+1 种基金the Research Project of Fujian Provincial Health and Family Planning Commission,No.2014-ZQN-JC-32a grant from the Platform for Preclinical Studies of Traditional Chinese Medicine and Quality Control Engineering Technology Research Center of Fujian Province in China,No.2009Y2003
文摘Salidroside,the main active ingredient extracted from Rhodiola crenulata,has been shown to be neuroprotective in ischemic cerebral injury,but the underlying mechanism for this neuroprotection is poorly understood.In the current study,the neuroprotective effect of salidroside on cerebral ischemia-induced oxidative stress and the role of the nuclear factor erythroid 2-related factor 2(Nrf2)pathway was investigated in a rat model of middle cerebral artery occlusion.Salidroside(30 mg/kg)reduced infarct size,improved neurological function and histological changes,increased activity of superoxide dismutase and glutathione-S-transferase,and reduced malon-dialdehyde levels after cerebral ischemia and reperfusion.Furthermore,salidroside apparently increased Nrf2 and heme oxygenase-1 expression.These results suggest that salidroside exerts its neuroprotective effect against cerebral ischemia through anti-oxidant mechanisms and that activation of the Nrf2 pathway is involved.The Nrf2/antioxidant response element pathway may become a new therapeutic target for the treatment of ischemic stroke.
基金supported by a grant from the Research Project of Fujian Provincial Health and Family Planning Commission of China,No.2014-ZQN-JC-32a grant from the Project of Fujian Province Office of Education of China,No.JZ160442+1 种基金the Natural Science Foundation of Fujian Province of China,No.2018J01855a grant from the Platform for Preclinical Studies of Traditional Chinese Medicine and Quality Control Engineering Technology Research Center of Fujian Province of China,No.2009Y2003
文摘Recovery following stroke involves neurogenesis and axonal remodeling within the ischemic brain. Gualou Guizhi decoction (GLGZD) is a Chinese traditional medicine used for the treatment of post-stroke limb spasm. GLGZD has been reported to have neuroprotective effects in cerebral ischemic injury. However, the effects of GLGZD on neurogenesis and axonal remodeling following cerebral ischemia remain unknown. In this study, a rat model of focal cerebral ischemia/reperfusion was established by middle cerebral artery occlusion. Neurologi- cal function was assessed immediately after reperfusion using Longa's 5-point scoring system. The rats were randomly divided into vehicle and GLGZD groups. Rats in the sham group were given sham operation. The rats in the GLGZD group were intragastrically administered GLGZD, once daily, for 14 consecutive days. The rats in the vehicle and sham groups were intragastrically administered distilled water. Modified neurological severity score test, balance beam test and foot fault test were used to assess motor functional changes. Nissl staining was performed to evaluate histopathological changes in the brain. Immunofluorescence staining was used to examine cell proliferation using the marker 5-bromo-2'-deoxyuridine (BrdU) as well as expression of the neural precursor marker doublecortin (DCX), the astrocyte marker glial fibrillary acidic protein (GFAP) and the axon regeneration marker growth associated protein-43 (GAP-43). GLGZD substan- tially mitigated pathological injury, increased the number of BrdU, DCX and GFAP-immunoreactive cells in the subventricular zone of the ischemic hemisphere, increased GAP-43 expression in the cortical peri-infarct region, and improved motor function. These findings suggest that GLGZD promotes neurological functional recovery by increasing cell proliferation, enhancing axonal regeneration, and in- creasing the numbers of neuronal precursors and astrocytes in the peri-infarct area.