High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,...High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,N2physisorption,27Al magic angle spinning nuclear magnetic resonance(MAS NMR),and temperature-programmed desorption of ammonia results indicated that the hightemperature treatment at 650℃ hardly affected the inherent crystal and texture of HZSM-5zeolites but facilitated the conversion of framework Al to extra-framework Al,reducing the acid site and enhancing the acid strength.Moreover,the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking,promoting the conversion and light olefins yield while inhibiting coke formation.Based on the kinetic and mechanism analysis,the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al,which enhanced the acid strength,facilitated the bimolecular reaction,and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking.展开更多
In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering comp...In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering complex boundary shapes.Utilizing radial basis function point interpolation,the method approximates shape functions for unknown functions within the nodal influence domain.The shape functions constructed by the aforementioned meshless interpolation method haveδ-function properties,which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells.Moreover,the meshless method offers greater flexibility and freedom compared to grid cell discretization,making it simpler to discretize complex geometries.A variational principle for the flow control equation group is introduced using a weighted least squares meshless method,and the pressure distribution is solved implicitly.Example results demonstrate that the computational outcomes of the meshless point cloud model,which has a relatively small degree of freedom,are in close agreement with those of the Discrete Fracture Model(DFM)employing refined grid partitioning,with pressure calculation accuracy exceeding 98.2%.Compared to high-resolution grid-based computational methods,the meshless method can achieve a better balance between computational efficiency and accuracy.Additionally,the impact of fracture half-length on the productivity of horizontal wells is discussed.The results indicate that increasing the fracture half-length is an effective strategy for enhancing production from the perspective of cumulative oil production.展开更多
Colorectal cancer(CRC)is one of the most common cancers and supplementation of probiotics may be a promising intervention method. The present study aimed to investigate the anti-CRC effects of Lactiplantibacillus plan...Colorectal cancer(CRC)is one of the most common cancers and supplementation of probiotics may be a promising intervention method. The present study aimed to investigate the anti-CRC effects of Lactiplantibacillus plantarum KX041 on a CRC mouse model. The CRC mice were induced by 10 mg/kg azoxymethane and 2% dextran sulfate sodium. L. plantarum KX041 was orally administrated once daily(1 × 10^(9) CFU/mouse). Results showed that L. plantarum KX041 could significantly inhibit inflammation, tumor formation, and induce tumor cells apoptosis. Moreover, this probiotic could ameliorate the damage of intestinal barrier by recovering tight junction protein expression(like Occludin, Claudin-1, and ZO-1)and preventing goblet cell loss. Furthermore, the oxidative stress was alleviated by increasing the level of antioxidant mediators(like GSH and SOD)and reducing the level of oxidative mediators(like MDA and MPO). In addition, treatment with L. plantarum KX041 could directly regulate gut microbiota, thereby increasing the abundance of beneficial bacteria(like SCFAs-producing bacteria, Akkermansia)and decreasing the abundance of harmful bacteria(like pro-inflammatory bacteria, Parasutterella), which in turn raised SCFAs levels and lowered LPS levels. In conclusion, L. plantarum KX041 could effectively ameliorate CRC via reshaping intestinal microenvironment, alleviating inflammation, maintaining intestinal permeability, and attenuating oxidative stress.展开更多
目的探讨富含亮氨酸重复序列/Ⅲ型纤维连接蛋白4(leucine-rich repeat and fibronectin typeⅢdomain-containing protein 4,LRFN4)在胃癌组织中的表达情况,并分析LRFN4表达水平与胃癌患者临床病理参数和预后的关系。方法收集2017年1月...目的探讨富含亮氨酸重复序列/Ⅲ型纤维连接蛋白4(leucine-rich repeat and fibronectin typeⅢdomain-containing protein 4,LRFN4)在胃癌组织中的表达情况,并分析LRFN4表达水平与胃癌患者临床病理参数和预后的关系。方法收集2017年1月至12月于中山大学附属第一医院胃肠外科中心确诊并行手术治疗的胃癌患者组织标本8对(包含胃癌组织和癌旁正常组织),并选取2004年1月至2005年12月在同一中心行手术治疗的117例胃癌患者的术后组织标本制成胃癌组织芯片。分析LRFN4在癌症基因组图谱(the cancer genome atlas,TCGA)数据库胃癌数据集中的表达情况,应用蛋白质印迹法及实时荧光定量聚合酶链反应检测LRFN4在8对新鲜胃癌组织及癌旁正常组织中的表达,应用免疫组织化学检测LRFN4在胃癌组织芯片中的表达。分析不同LRFN4表达水平的胃癌患者其临床病理参数的差异。应用Kaplan-Meier法分析不同LRFN4表达水平的胃癌患者的预后情况。应用单因素和多因素Cox回归分析法分析胃癌患者预后的影响因素。结果LRFN4在TCGA数据库胃癌数据集的胃癌组织以及新鲜胃癌组织中呈高表达状态。LRFN4高表达的患者,表现出更大的肿瘤大小以及更为进展的T分期、N分期、M分期和TNM分期(均P<0.05),其预后也较差(P<0.001)。单因素和多因素Cox回归分析提示LRFN4在胃癌组织中的高表达是影响胃癌患者预后的独立危险因素(HR=3.898,95%CI 2.273~6.686,P<0.001)。结论胃癌组织中LRFN4高表达与患者较差的预后相关,可能成为预测胃癌患者预后的生物标志物之一。展开更多
Colloidal particles,heterogeneous mixture with various organic components and continuous molecular weight(MW)distribution,is omnipresent in lake sediments and substantially influence the retention,transportation,and f...Colloidal particles,heterogeneous mixture with various organic components and continuous molecular weight(MW)distribution,is omnipresent in lake sediments and substantially influence the retention,transportation,and fate of contaminants in lake ecosystem.We sampled and extracted sedimentary colloids from different ecology regions in Taihu Lake,Jiangsu,East China,in June 2020,and they were further separated into four different particle size ranges by tangent ultrafiltration,and the properties of colloids were studied in various methods,including zeta potential analysis,transmission electron micrograph images(TEM),Fourier transformation infrared(FTIR),and 3D fluorescence.Results show that the surface of the colloids is covered with organic macromolecular substances,such as humuslike substances and protein-like substances.There were significant differences in molecular weight and fraction content of colloids in the sediments from macrophyte-dominant(MD)area and algae-dominant(AD)area in the lake.Colloids from MD area are mainly composed of humic acid,protein,and fulvic acid;the content of fulvic acid is lower than that of humic acid and protein.The humic acid exists mainly in small molecular weight(10-100 kDa),protein exists in mainly large molecular weight colloids(0.45-1μm).Colloids from AD area are mainly composed of humic acid,and mainly distributed in the molecular weight(10 kDa-0.45μm).The presence of humic acid inhibits effectively the agglomeration of the colloids.Especially,the stability of colloids is closely related to the molecular weight,with low molecular weight from MD area show higher stability.The existence of humic acid in colloids increases the electrostatic repulsion between colloidal particles,which can effectively inhibit the agglomeration of colloids,thus enhancing the stability of colloids.Furthermore,both monovalent and divalent electrolytes enhance colloidal aggregation,and the low-molecular-weight(LMW)colloid fraction exhibits higher stability efficiency than the high-molecular-weight(HMW)colloidal.展开更多
目的检索、评价并整合国内外新生儿肠内营养胃管留置管理的相关证据。方法系统检索英国医学杂志最佳临床实践网、Up To Date、CINAHL、加拿大医学会临床实践指南网、国际指南网、WHO指南网、美国国立指南库、医脉通、Cochrane图书馆、Pu...目的检索、评价并整合国内外新生儿肠内营养胃管留置管理的相关证据。方法系统检索英国医学杂志最佳临床实践网、Up To Date、CINAHL、加拿大医学会临床实践指南网、国际指南网、WHO指南网、美国国立指南库、医脉通、Cochrane图书馆、PubMed、中国知网、中国生物医学文献数据库、万方数据库、维普等数据库等网站和数据库中关于新生儿肠内营养胃管留置管理的临床决策、推荐实践、证据总结、临床实践指南、技术报告、专家共识、系统评价,由2名研究者独立进行方法学质量评价后,根据主题对证据进行提取与汇总,检索时限为建库至2023年5月。结果共纳入14篇文献,包括指南2篇、证据总结1篇、系统评价5篇、专家共识3篇、最佳实践2篇、随机对照研究1篇。最后总结包括适应与禁忌、置管前的准备与评估、胃管位置验证、胃管固定、胃管维护5个方面的22条证据。结论本研究通过系统检索国内外高级别的循证资源,对新生儿肠内营养胃管留置的管理进行证据总结,所总结的新生儿肠内营养胃管留置管理证据全面、实用,可为规范新生儿胃管留置管理管理提供循证依据,保证新生儿肠内营养安全,提高新生儿护理质量。展开更多
基金the financial support from the National Natural Science Foundation of China(21908010)Jilin Provincial Department of Science and Technology(20220101089JC)the Education Department of Jilin Province(JJKH20220694KJ)。
文摘High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,N2physisorption,27Al magic angle spinning nuclear magnetic resonance(MAS NMR),and temperature-programmed desorption of ammonia results indicated that the hightemperature treatment at 650℃ hardly affected the inherent crystal and texture of HZSM-5zeolites but facilitated the conversion of framework Al to extra-framework Al,reducing the acid site and enhancing the acid strength.Moreover,the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking,promoting the conversion and light olefins yield while inhibiting coke formation.Based on the kinetic and mechanism analysis,the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al,which enhanced the acid strength,facilitated the bimolecular reaction,and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking.
文摘In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering complex boundary shapes.Utilizing radial basis function point interpolation,the method approximates shape functions for unknown functions within the nodal influence domain.The shape functions constructed by the aforementioned meshless interpolation method haveδ-function properties,which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells.Moreover,the meshless method offers greater flexibility and freedom compared to grid cell discretization,making it simpler to discretize complex geometries.A variational principle for the flow control equation group is introduced using a weighted least squares meshless method,and the pressure distribution is solved implicitly.Example results demonstrate that the computational outcomes of the meshless point cloud model,which has a relatively small degree of freedom,are in close agreement with those of the Discrete Fracture Model(DFM)employing refined grid partitioning,with pressure calculation accuracy exceeding 98.2%.Compared to high-resolution grid-based computational methods,the meshless method can achieve a better balance between computational efficiency and accuracy.Additionally,the impact of fracture half-length on the productivity of horizontal wells is discussed.The results indicate that increasing the fracture half-length is an effective strategy for enhancing production from the perspective of cumulative oil production.
基金the financial support of Post-doctoral Start-up funding (2018) of Northwest A&F University (Z109021804)National Natural Science Foundation of China (31972043 and 32001652)。
文摘Colorectal cancer(CRC)is one of the most common cancers and supplementation of probiotics may be a promising intervention method. The present study aimed to investigate the anti-CRC effects of Lactiplantibacillus plantarum KX041 on a CRC mouse model. The CRC mice were induced by 10 mg/kg azoxymethane and 2% dextran sulfate sodium. L. plantarum KX041 was orally administrated once daily(1 × 10^(9) CFU/mouse). Results showed that L. plantarum KX041 could significantly inhibit inflammation, tumor formation, and induce tumor cells apoptosis. Moreover, this probiotic could ameliorate the damage of intestinal barrier by recovering tight junction protein expression(like Occludin, Claudin-1, and ZO-1)and preventing goblet cell loss. Furthermore, the oxidative stress was alleviated by increasing the level of antioxidant mediators(like GSH and SOD)and reducing the level of oxidative mediators(like MDA and MPO). In addition, treatment with L. plantarum KX041 could directly regulate gut microbiota, thereby increasing the abundance of beneficial bacteria(like SCFAs-producing bacteria, Akkermansia)and decreasing the abundance of harmful bacteria(like pro-inflammatory bacteria, Parasutterella), which in turn raised SCFAs levels and lowered LPS levels. In conclusion, L. plantarum KX041 could effectively ameliorate CRC via reshaping intestinal microenvironment, alleviating inflammation, maintaining intestinal permeability, and attenuating oxidative stress.
文摘目的探讨富含亮氨酸重复序列/Ⅲ型纤维连接蛋白4(leucine-rich repeat and fibronectin typeⅢdomain-containing protein 4,LRFN4)在胃癌组织中的表达情况,并分析LRFN4表达水平与胃癌患者临床病理参数和预后的关系。方法收集2017年1月至12月于中山大学附属第一医院胃肠外科中心确诊并行手术治疗的胃癌患者组织标本8对(包含胃癌组织和癌旁正常组织),并选取2004年1月至2005年12月在同一中心行手术治疗的117例胃癌患者的术后组织标本制成胃癌组织芯片。分析LRFN4在癌症基因组图谱(the cancer genome atlas,TCGA)数据库胃癌数据集中的表达情况,应用蛋白质印迹法及实时荧光定量聚合酶链反应检测LRFN4在8对新鲜胃癌组织及癌旁正常组织中的表达,应用免疫组织化学检测LRFN4在胃癌组织芯片中的表达。分析不同LRFN4表达水平的胃癌患者其临床病理参数的差异。应用Kaplan-Meier法分析不同LRFN4表达水平的胃癌患者的预后情况。应用单因素和多因素Cox回归分析法分析胃癌患者预后的影响因素。结果LRFN4在TCGA数据库胃癌数据集的胃癌组织以及新鲜胃癌组织中呈高表达状态。LRFN4高表达的患者,表现出更大的肿瘤大小以及更为进展的T分期、N分期、M分期和TNM分期(均P<0.05),其预后也较差(P<0.001)。单因素和多因素Cox回归分析提示LRFN4在胃癌组织中的高表达是影响胃癌患者预后的独立危险因素(HR=3.898,95%CI 2.273~6.686,P<0.001)。结论胃癌组织中LRFN4高表达与患者较差的预后相关,可能成为预测胃癌患者预后的生物标志物之一。
基金Supported by the National Natural Science Foundation of China(Nos.42007332,51979137)the Natural Science Foundation of Jiangsu Province(No.20KJB610001)。
文摘Colloidal particles,heterogeneous mixture with various organic components and continuous molecular weight(MW)distribution,is omnipresent in lake sediments and substantially influence the retention,transportation,and fate of contaminants in lake ecosystem.We sampled and extracted sedimentary colloids from different ecology regions in Taihu Lake,Jiangsu,East China,in June 2020,and they were further separated into four different particle size ranges by tangent ultrafiltration,and the properties of colloids were studied in various methods,including zeta potential analysis,transmission electron micrograph images(TEM),Fourier transformation infrared(FTIR),and 3D fluorescence.Results show that the surface of the colloids is covered with organic macromolecular substances,such as humuslike substances and protein-like substances.There were significant differences in molecular weight and fraction content of colloids in the sediments from macrophyte-dominant(MD)area and algae-dominant(AD)area in the lake.Colloids from MD area are mainly composed of humic acid,protein,and fulvic acid;the content of fulvic acid is lower than that of humic acid and protein.The humic acid exists mainly in small molecular weight(10-100 kDa),protein exists in mainly large molecular weight colloids(0.45-1μm).Colloids from AD area are mainly composed of humic acid,and mainly distributed in the molecular weight(10 kDa-0.45μm).The presence of humic acid inhibits effectively the agglomeration of the colloids.Especially,the stability of colloids is closely related to the molecular weight,with low molecular weight from MD area show higher stability.The existence of humic acid in colloids increases the electrostatic repulsion between colloidal particles,which can effectively inhibit the agglomeration of colloids,thus enhancing the stability of colloids.Furthermore,both monovalent and divalent electrolytes enhance colloidal aggregation,and the low-molecular-weight(LMW)colloid fraction exhibits higher stability efficiency than the high-molecular-weight(HMW)colloidal.
文摘目的检索、评价并整合国内外新生儿肠内营养胃管留置管理的相关证据。方法系统检索英国医学杂志最佳临床实践网、Up To Date、CINAHL、加拿大医学会临床实践指南网、国际指南网、WHO指南网、美国国立指南库、医脉通、Cochrane图书馆、PubMed、中国知网、中国生物医学文献数据库、万方数据库、维普等数据库等网站和数据库中关于新生儿肠内营养胃管留置管理的临床决策、推荐实践、证据总结、临床实践指南、技术报告、专家共识、系统评价,由2名研究者独立进行方法学质量评价后,根据主题对证据进行提取与汇总,检索时限为建库至2023年5月。结果共纳入14篇文献,包括指南2篇、证据总结1篇、系统评价5篇、专家共识3篇、最佳实践2篇、随机对照研究1篇。最后总结包括适应与禁忌、置管前的准备与评估、胃管位置验证、胃管固定、胃管维护5个方面的22条证据。结论本研究通过系统检索国内外高级别的循证资源,对新生儿肠内营养胃管留置的管理进行证据总结,所总结的新生儿肠内营养胃管留置管理证据全面、实用,可为规范新生儿胃管留置管理管理提供循证依据,保证新生儿肠内营养安全,提高新生儿护理质量。
