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生成式人工智能赋能本科生科研能力培养——ChatGPT支持的CUREs教学模式 被引量:19
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作者 吴忭 李凤鸣 胡艺龄 《现代远程教育研究》 CSSCI 北大核心 2024年第3期3-10,28,共9页
为促进高等教育中高素质创新人才培养,构建以学生为中心的科研训练与课程教学整合模式是有效途径。当前基于课程的本科生科研体验(CUREs)教学模式虽在增强学生对科学本质的理解等方面具有一定优势,但在激发学生研究动机方面存在一些不... 为促进高等教育中高素质创新人才培养,构建以学生为中心的科研训练与课程教学整合模式是有效途径。当前基于课程的本科生科研体验(CUREs)教学模式虽在增强学生对科学本质的理解等方面具有一定优势,但在激发学生研究动机方面存在一些不足。将支持高效反馈的生成式人工智能ChatGPT引入人机协作研究过程中,有助于改善学生的科研体验,推动科研项目化学习。通过对ChatGPT支持的CUREs教学模式的设计与实施,发现该模式有助于培养学生的科研能力,提升他们的科研知识水平、科研技能水平和科研情感水平。尽管学生认同该教学模式的有效性和易用性,但其实际效果的发挥仍需人类智慧的参与。未来需要持续升级和优化生成式人工智能技术,确保技术应用高效且符合伦理标准;应用生成式人工智能技术重构教学模式,并通过长周期、跨场域实践检验其应用效果;强调人工智能与人类智慧的互补协作,真正实现生成式人工智能赋能学生科研能力提升。 展开更多
关键词 生成式人工智能 ChatGPT 科研能力 cures 教学模式
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Huu S. TIEU Request for FDA to Establish Regenerating Human Cells as Law on December 13, 2016 President Barack H. Obama Signed the 21st Century CURES Act into FDA Regulation and Law
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作者 Huu S. Tieu Martin F. Loeffler Edgar A. Ayala 《Open Journal of Regenerative Medicine》 CAS 2022年第3期55-62,共8页
Background and Aims: On November 24, 2009, Huu S. TIEU and Golden Sunrise Pharmaceutical, Inc. (Golden Sunrise) applied for the Technology and Innovation to be reviewed and evaluated by the U.S. Food and Drug Administ... Background and Aims: On November 24, 2009, Huu S. TIEU and Golden Sunrise Pharmaceutical, Inc. (Golden Sunrise) applied for the Technology and Innovation to be reviewed and evaluated by the U.S. Food and Drug Administration (FDA). In the review and evaluation, it was requested by Golden Sunrise designated the new indications for this application under Serious or Life-threatening conditions or diseases. Discussions followed with the FDA, Huu S. TIEU, and Golden Sunrise for FDA approval on new products and new indications on existing new Medical Technology and Innovation. It was agreed in Year-2015 that the FDA would take the request for new indications to the United States Congress to establish into FDA regulation and law. At that time the following was the FDA Guidance—“Emergency Use of a Test Article” is exempt from prior Institutional Review Board or Advisory Committee evaluation and approval, provided that such emergency use is reported to the Institutional Review Board within five working days after use. Expedited Institutional Review Board or Advisory Committee approval is not permitted in emergency use. There has been no funding to the authors for the writing or publication of this article. Methods: It was requested by Huu S. TIEU and Golden Sunrise in documents given to the FDA to have Serious or Life-threatening conditions or diseases indication be recognized by law. On August 08, 2015, the FDA responding to this request took the documentation produced by Golden Sunrise to the United States Congress on behalf of Golden Sunrise and Huu S. TIEU. This article encompasses the FDA regulatory method as well as the discussion and results of the establishment of the FDA and the 21<sup>st</sup> Century Cures Act. Results: On December 13, 2016, H.R.34—114<sup>th</sup> United States Congress (2015-2016) 21<sup>st</sup> Century CURES Act was signed into law by President Barack H. Obama which included the Serious or Life-threatening indication to be written into the CURES Act. In summary, the 21<sup>st</sup> Century Cures Act is a landmark piece of legislation that enjoyed broad bipartisan support in United States Congress. The main goals of the Act are impactful and should transform future cancer, neurologic, and precision medicine or drug research as well as aid individuals with mental health is intended to facilitate the prompt approval of new agents and devices, clinicians should be aware of the types of data behind an approval and take this into consideration when developing illnesses and opioid dependence. However, some of the wording within the CURES Act regarding the drug and device approval process may bring pause to health care providers including pharmacists. Although this wording and implementing care plans and counseling patients. The 21<sup>st</sup> Century Cures Act was incorporated into laws and regulations by the FDA under § 3072 of the Act grants the Commissioner of Food and Drugs the authority to appoint and set the annual rate of pay for outstanding and qualified candidates to scientific, technical, or professional positions that support the development, review, and regulation of medical products. 展开更多
关键词 Huu S. TIEU Request for FDA to Establish Regenerating Human Cells as Law on December 13 2016 President Barack H. Obama Signed the 21st Century cures Act into FDA Regulation and Law
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Cures for expansion shock and shock instability of Roe scheme based on momentum interpolation mechanism
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作者 Xuesong LI Xiaodong REN Chunwei GU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第4期455-466,共12页
The common defects of the Roe scheme are the non-physical expansion shock and shock instability. By removing the momentum interpolation mechanism(MIM), an improved method with several advantages has been presented to ... The common defects of the Roe scheme are the non-physical expansion shock and shock instability. By removing the momentum interpolation mechanism(MIM), an improved method with several advantages has been presented to suppress the shock instability. However, it cannot prevent the expansion shock and is incompatible with the traditional curing method for expansion shock. To solve the problem, the traditional curing mechanism is analyzed. Effectiveness of the traditional curing method is discussed,and several defects are identified, one of which leads to incompatibility between curing shock instability and expansion shock. Consequently, an improved Roe scheme is proposed, which is with low computational costs, concise, easy to implement, and robust.More importantly, the proposed scheme can simultaneously solve the problem of shock instability and expansion shock without additional costs. 展开更多
关键词 Roe scheme expansion shock shock instability momentum interpolation mechanism(MIM) robust curing method
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Gemcitabine cures metastatic hepatic carcinoma and bone metastasis
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作者 Chih-Chao Yang Wai-Kevng Chow +1 位作者 Yen-Chun Peng Ran-Ching Wang 《World Journal of Hematology》 2013年第4期115-118,共4页
We report a case of a 59-year-old gentleman who had suffered from low back pain for several months.Abdominal sonogram showed multiple heteroechoic nodules in the bilateral liver and an enlarged pancreatic head.Abdomin... We report a case of a 59-year-old gentleman who had suffered from low back pain for several months.Abdominal sonogram showed multiple heteroechoic nodules in the bilateral liver and an enlarged pancreatic head.Abdominal computer tomography(CT)favored pancreas head tumor with liver and bone metastasis.Endoscopic retrograde cholangiopancreatography(ERCP)disclosed pancreatic duct invasion over the distal portion of the pancreatic duct with prestenotic dilatation.Liver biopsy showed undifferentiated carcinoma.As suggested by the pathologist,the nasopharyngeal area was checked by the ear,nose and throat doctor,was negative and nasopharyngeal carcinoma was ex-cluded.Therefore,the patient was treated with Gemcitabine(1500 mg/wk),as the suggested treatment schedule,for 24 wk in opioid dependency program.Sequential abdominal CT during follow up showed the disappearance of liver metastasis and shrinkage of the pancreatic tumor.Repeated ERCP after treatment showed re-channelization of the pancreatic duct.During11 years of follow up,5 CT scans disclosed not only the disappearance of the hepatic tumor but also no cancer recurrence.Progressive shrinkage of pancreatic head was also noted.Therefore,we can say this malignant case was cured by monotherapy with gemcitabine. 展开更多
关键词 GEMCITABINE Gemza CURE METASTATIC HEPATIC CARCINOMA UNDIFFERENTIATED CARCINOMA Bone metastasis
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Hydration, Microstructure, and Properties of Sulphoaluminate Cement in Pure Water and Simulated Seawater
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作者 MA Jie 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期187-193,共7页
Paste and mortar specimens were prepared with sulfoaluminate cement(SAC),P⋅O 42.5 ordinary Portland cement(OPC),and standard sand,and mixed and cured with pure water and artificial seawater,respectively.The mechanical... Paste and mortar specimens were prepared with sulfoaluminate cement(SAC),P⋅O 42.5 ordinary Portland cement(OPC),and standard sand,and mixed and cured with pure water and artificial seawater,respectively.The mechanical properties of mortar specimens were tested.Hydration and microstructure of paste specimens were also investigated using X-ray diffraction(XRD),scanning electron microscope(SEM),and 27Al nuclear magnetic resonance(NMR),respectively.The results indicate that SAC mortar samples mixed and cured by seawater have faster strength growth before 28 d and higher compressive strength than OPC mortar samples.Compared to curing in deionized water,the hydration products of SAC are somewhat coarser when cured in simulated seawater.The evolution of aluminum phase hydration products during the hydration process of SAC mixed and cured in simulated seawater is quite different from that of OPC.From 3 to 28 d,the content of each aluminum phase hydration product in SAC paste cured in simulated seawater changed little,while that in OPC paste changed significantly;for example,from 7 to 28 d,the content of ettringite(AFt)in OPC paste increased significantly.This type of AFt formed loosely,harming the mortar's microstructure. 展开更多
关键词 sulfoaluminate cement seawater mixing and curing 27Al NMR AFt
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Progress in the Binding of Chloride Ions in Cement-based Materials
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作者 DU Xixian LI Gang +2 位作者 WANG Aiqin CAO Aoli SUN Jianren 《材料导报》 北大核心 2025年第13期100-113,共14页
Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characterist... Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characteristics.The composition of the cement-based material,including the type of cement and auxiliary materials,greatly influences the ability of the material to bind Cl^(-),and varied components result in varying binding beha-vior of the Cl^(-).Simultaneously,the Cl^(-)binding process in concrete is influenced by both the internal and exterior surroundings,as well as the curing practices.These factors impact the hydration process of the cement and the internal pore structure of the concrete.Currently,mathematical theories and molecular dynamics simulations have increasingly been employed as the prevalent methods for examining the binding behaviors of Cl^(-)in concrete.These techniques are extensively utilized for predicting the lifespan and conducting microscopic studies of reinforced concrete in Cl^(-)settings.This work proposes recommendations for future research based on a summary of experimental and simulation investigations on Cl^(-)binding.Which will offer theoretical guidance for studying the binding of Cl^(-)in cement-based materials. 展开更多
关键词 cement-based material chloride binding auxiliary material environment curing practice simulation
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Rheology,curing behavior,and porosity evolution in dual curing direct ink writing of carbon/carbon composites
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作者 Xin YE Qian LU +3 位作者 Lu-tong WU Ming-liang XU XIANG Xiong Feng-ze JIANG 《Transactions of Nonferrous Metals Society of China》 2025年第9期3057-3073,共17页
To overcome reliance on molds and the difficulty of fabricating complex geometries with traditional C/C composites,direct ink writing(DIW)with UV/heat dual curing was employed to produce high-performance C/C composite... To overcome reliance on molds and the difficulty of fabricating complex geometries with traditional C/C composites,direct ink writing(DIW)with UV/heat dual curing was employed to produce high-performance C/C composites.The rheological properties of the composite inks were systematically analyzed to assess the effects of phenolic resin(PR)and carbon fiber(CF)content.Results show pronounced shear-thinning behavior and strong thixotropy-both essential for stable DIW.Additionally,UV/heat curing behavior was characterized to provide theoretical insights for optimizing curing parameters.Notably,CF addition is found to significantly attenuate UV light penetration compared to pure PR.As CF content increases,the critical UV irradiation energy rises sharply from 68.47 to 911.19 mJ/cm^(2),necessitating precise adjustments to curing parameters.Preforms were pyrolyzed in a carbon tube furnace to examine pore-formation characteristics,and chemical vapor infiltration(CVI)was applied to filling the resulting pores,yielding C/C composites with a flexural strength of 115.19 MPa. 展开更多
关键词 C/C composites dual curing direct ink writing RHEOLOGY curing behavior chemical vapor infiltration
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Activity of Electrolytic Manganese Residue under High Temperature Calcination-mechanical Coupling and the Solidification Mechanism of Heavy Metals
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作者 QIAO Hongxia FU Yong +2 位作者 FENG Qiong LI Yanqi JIA Zhenyu 《Journal of Wuhan University of Technology(Materials Science)》 2025年第4期953-966,共14页
The effects of calcination temperature and mechanical ball milling on the physicochemical properties of electrolytic manganese residue(EMR),mineral phase transition,pozzolanic activity,and pore structure were studied.... The effects of calcination temperature and mechanical ball milling on the physicochemical properties of electrolytic manganese residue(EMR),mineral phase transition,pozzolanic activity,and pore structure were studied.The experimental results show that the strength activity index(SAI)of 20%EMR mixed mortar at 28 days is 90.54%,95.40%,and 90.73%,respectively,after pretreatment with EMR at 800℃calcined for 3,5,and 8 min.This is mainly attributed to the high temperature decomposition of gypsum dihydrate to form activated calcium oxide.In addition,high temperature and mechanical force destroys the Si-O chemical bond and promotes the formation of calcium silicate gel structure.Due to the existence of a large number of gypsum phases in EMR mixed mortar,a large number of ettringite,C-S-H,aluminosilicate,C-A-S-H,and AFm are formed,which strongly verifies the volcanic activity of EMR.The leaching test shows that high temperature calcination has a significant effect on the stabilization of NH_(3)-N.However,the curing effect of Mn^(2+)is significant only in the calcination at 1000℃,but both Mn^(2+)and NH_(3)-N in the calcined EMR are higher than the emission standard.The encapsulation effect of EMR composite mortar provided by hydration products,and the buffering capacity of the Si-Al system for solidification of heavy metals and strong alkalis are conducive to the stability of Mn^(2+)and NH_(3)-N.After the EMR mixed mortar is aged for 3 days,Mn and NH_(3)-N are completely lower than the emission standard.In general,the EMR mixed mortar can meet the requirements for green building use. 展开更多
关键词 electrolytic manganese residue CALCINATION GRINDING pozzolanic activity LEACHING curing mechanism
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Synthesis of a Novel Silicon-containing Epoxy Compound and Its Mechanical Properties for Amine Curing
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作者 QU Yafen YU Yanling HUANG Biwu 《Journal of Wuhan University of Technology(Materials Science)》 2025年第4期1169-1175,共7页
[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was synthesized,using tert-butyldimethylsilane(TBDMS)and 1,2-epoxy-4-vinylcyclohexane(EVC)as the main raw materials and tris(triphenylphosphine)chlororhodium(I)[... [2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was synthesized,using tert-butyldimethylsilane(TBDMS)and 1,2-epoxy-4-vinylcyclohexane(EVC)as the main raw materials and tris(triphenylphosphine)chlororhodium(I)[RhCl(Ph3P)3]as the catalyst.[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane is a novel kind of silicon-containing epoxide.The factors affecting the reaction yield,such as catalyst use,reaction time and reaction temperature,were investigated,and the synthesized product was characterized and analyzed by FT-IR and 1H-NMR.A series of amine-curing resins were prepared with[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane,bisphenol A epoxy resin(E-51)and modified amine(593 amine).The mechanical properties of cured splines with the different proportions of amine-curing resins were tested.When the content of 593 amine was 20%,the content of E-51 was 75%and the amount of[2-(3,4-epoxy-cyclohexyl)ethyl]dimethyltert-butylsilane was 5%,the mechanical properties of the cured splines were the best with the tensile strength being 23.3 MPa,the elongation at break being 7.8%,and the Young's modulus being 421.3 MPa. 展开更多
关键词 epoxide resin SILICONE amine curing DILUENTS mechanical properties
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Salt reduction in cured meat products:a review on strategies and mechanisms
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作者 Qi Chen Jinxuan Cao +3 位作者 Wenhai She Weidong Bai Xiaofang Zeng Hao Dong 《Food Science and Human Wellness》 2025年第3期864-879,共16页
Sodium chloride is one of the most widely used additives in meat curing.However,cured meat products contribute to a portion of the total sodium dietary intake.Consumers and researchers'concern about excessive sodi... Sodium chloride is one of the most widely used additives in meat curing.However,cured meat products contribute to a portion of the total sodium dietary intake.Consumers and researchers'concern about excessive sodium intake has prompted the food industry to consider ways to reduce salt content of cured meat products.The aim of this review is to provide a broad but comprehensive understanding of salt reduction strategies for cured meat products.The implications and limitations of each approach were discussed.Green technologies treatments,such as ultrasonic technology,high-pressure processing,seem to be potential to ensure microbiological safety in low-sodium cured meat products.However,these novel technologies can cause protein and fat oxidization in meat products.A combination of multiple treatments could give the desired effect.In addition,different parameter conditions need to be set according to the specific meat to achieve better salt reduction effect. 展开更多
关键词 Salt reduction Cured meat products Ultrasonic technology Salt substitutes High-pressure processing
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Effect of Compound Early-Strength Internal Curing Agents on Properties of Cement-Based Materials
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作者 XU Pengjie LIU Rongjin +2 位作者 GAO Tianyu CHEN Ping WAN Dandan 《Journal of Wuhan University of Technology(Materials Science)》 2025年第5期1397-1406,共10页
To address the negative impact of an internal curing agent on strength while preserving its ability to resist autogenous shrinkage,we investigated the incorporation of triethanolamine and triisopropanolamine as early-... To address the negative impact of an internal curing agent on strength while preserving its ability to resist autogenous shrinkage,we investigated the incorporation of triethanolamine and triisopropanolamine as early-strength components.These additives were combined with an internal curing agent to prepare a compound early-strength internal curing agent so as to investigate how compound early-strength internal curing agents affect the mechanical characteristics and volume stability of mortar.This was assessed using a battery of tests,including strength,autogenous shrinkage,internal relative humidity,mercury intrusion porosimetry,X-ray powder diffraction,and scanning electron microscopy.These results indicate that the compound early-strength internal curing agent effectively maintains the volume stability of the mortar without compromising its early mechanical properties.The compressive strength ratios of the mortar mixed with the compound early-strength internal curing agent were 109.45% at 3 days and 119% at 7 days,indicating significant improvement compared with the internal curing agent.Furthermore,the 7-day autogenous shrinkage rate of the mortar was-56.78μm/m.The proportion of hazardous-grade pores larger than 100 nm was reduced to 3.54%,and the pore distribution was uniform.This study introduces innovative ideas and methods for mitigating the adverse effects of internal curing agents on the early strength of mortar. 展开更多
关键词 internal curing agent early-strength components mechanical properties volume stability autogenous shrinkage
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Enhancement of Mechanical Properties of Natural Rubber Filled Activated Carbon Materials from Agricultural Waste
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作者 Pollawat Charoeythornkhajhornchai Piyamas Saehia +2 位作者 Thidaporn Butchan Nawapol Lertumpai Worawut Muangrat 《Journal of Renewable Materials》 2025年第4期817-827,共11页
Herein,cure characteristics,morphology,and mechanical properties of natural rubber filled with activated carbon-based materials were investigated.Carbon-based materials were prepared from bagasse,coffee grounds and pi... Herein,cure characteristics,morphology,and mechanical properties of natural rubber filled with activated carbon-based materials were investigated.Carbon-based materials were prepared from bagasse,coffee grounds and pineapple crowns by the pyrolysis method at temperatures in the range of 300℃.As-synthesized carbon materials were characterized by optical microscopy(OM),scanning electron microscopy(SEM),and Fourier-transform infrared spectroscopy(FTIR)to analyze size distribution,morphology,and functional groups,respectively.OM and SEM analysis revealed that particles,flakes,and a small quantity of fiber-like carbon were obtained using bagasse and pineapple crown as raw materials,while honeycomb-like carbon materials can be derived from coffee grounds.To investigate the mechanical properties,natural rubber was filled with carbon black and as-synthesized carbon materials by the internal mixing and compression molding process.Transmission electron microscopy(TEM)was utilized to characterize the dispersion of carbon materials in the rubber matrix.The results of tensile testing showed that the natural rubber mixed with as-synthesized carbon materials from pineapple crowns exhibited 54%and 74%improvement in the ultimate tensile strength and Young’s modulus,respectively,compared with natural rubber without filled carbon materials.The enhancement in mechanical properties by activated carbon materials derived from pineapple crowns can be attributed to the flake-and fiber-like structures and good dispersion of carbon materials in the rubber matrix.In addition,it is higher than that of rubber mixed with carbon black.The results demonstrated that as-synthesized carbon materials from pineapple crowns have the potential materials to substitute carbon black in the rubber compound industry. 展开更多
关键词 Carbon materials agricultural waste natural rubber cure characteristics mechanical properties
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Retrospective analysis of factors influencing the self-healing of patients with enterocutaneous fistulas receiving conservative treatment
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作者 Zhuo-Nan Zhuang Rui Zhao Yuan-Xin Li 《World Journal of Gastrointestinal Oncology》 2025年第3期104-112,共9页
BACKGROUND Enterocutaneous(EC)fistula incidence has been increasing in China,along with increases in the volume and complexity of surgeries.The conservative treatment strategy has been analyzed to improve the treatmen... BACKGROUND Enterocutaneous(EC)fistula incidence has been increasing in China,along with increases in the volume and complexity of surgeries.The conservative treatment strategy has been analyzed to improve the treatment outcomes for patients with EC fistulas and reduce the need for reoperation.AIM To analyze the clinical data of patients undergoing conservative treatment for EC fistulas and identify the factors that promote self-healing.These findings provide a reference for improving the clinical cure rate of EC fistulas with conservative treatment.METHODS The clinical data of 91 patients with EC fistulas who underwent conservative treatment were collected.The relationships between the cure rate and characteristics such as age,sex,body mass index,albumin level,primary disease,cause of the fistula,location of the fistula,number of fistulas,nature of the fistula,infection status,diagnostic methods,nutritional support methods,somatostatin therapy,growth hormone therapy,and fibrin glue therapy were analyzed.RESULTS A comparison of the basic patient characteristics between the two groups revealed statistically significant differences in primary disease(P=0.044),location of the fistula(P=0.006),number of fistulas(P=0.007),and use of adhesive sealing(χ2=12.194,P<0.001)between the uncured and cured groups.The use of fibrin glue was a significant factor associated with a cure for fistulas(odds ratio=5.459,95%CI:1.958-15.219,P=0.01).CONCLUSION The cure rate of patients with a single EC fistula can be effectively improved via conservative treatment combined with the use of biological fibrin glue to seal the fistula. 展开更多
关键词 Enterocutaneous fistula Conservative treatment Fibrin glue Fistula sealing Cure rate
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CHINA’S “NEW YEAR”,THE WORLD'S“SPRING FESTIVAL”
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作者 Wang Yandan Huang Wenjuan(Translated) 《China's Tibet》 2025年第1期70-70,共1页
On December 4,2024,UNESCO officially inscribed the"Spring Festival,social practice of the Chinese people in celebration of the traditional new year"on the Representative List of the Intangible Cultural Herit... On December 4,2024,UNESCO officially inscribed the"Spring Festival,social practice of the Chinese people in celebration of the traditional new year"on the Representative List of the Intangible Cultural Heritage of Humanity.To date,a total of 44 cultural elements from China have been inscribed on this prestigious list,securing China's position as the leading country worldwide in terms of cultural heritage recognitions.The Spring Festival,widely regarded as the most significant and vibrant festival in China,is evolving from a celebration rooted in"Chinese time"to a globally shared cultural event. 展开更多
关键词 UNESCO globally CURING
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Enhanced durability of a novel thiol-epoxy network thermosets with excellent hygrothermal and chemical resistance
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作者 Chunshi He Linqing Li +3 位作者 Yuanrong Sun Xuefang Wang Jie Ren Jianbo Li 《Chinese Chemical Letters》 2025年第6期521-528,共8页
Epoxy resin is widely used in electronic packaging due to its exceptional performance,particularly the low-temperature curable thiol/epoxy system,which effectively minimizes thermal damage to sensitive electronic comp... Epoxy resin is widely used in electronic packaging due to its exceptional performance,particularly the low-temperature curable thiol/epoxy system,which effectively minimizes thermal damage to sensitive electronic components.However,the majority of commercial thiol curing agents contain hydrolysable ester bonds and lack rigid structures,which induces most of thiol/epoxy systems still suffering from unsatisfactory heat resistance and hygrothermal resistance,significantly hindering their application in electronic packaging.In this study,we synthesized a tetrafunctional thiol compound,bis[3-(3-sulfanylpropyl)-4-(3-sulfanylpropoxy)phenyl]sulfone(TMBPS)with rigid and ester-free structures to replace traditional commercial thiol curing agents,pentaerythritol tetra(3-mercaptopropionate)(PETMP).Compared to the PETMP/epoxy system,the TMBPS/epoxy system exhibited superior comprehensive properties.The rigid structures of bisphenol S-type tetrathiol enhanced the heat resistance and mechanical properties of TMBPS/epoxy resin cured products,outperforming those of PETMP/epoxy resin cured products.Notably,the glass transition temperature of TMBPS/epoxy resin cured products was 74.2℃which was 11.8°C higher than that of PETMP cured products.Moreover,the ester-free structure in TMBPS contributed to its enhanced resistance to chemicals and hygrothermal conditions.After undergoing 1000 h of hightemperature and high-humidity aging,the tensile strength and adhesion strength of TMBPS-cured products were 73.33 MPa and 3.39 MPa,respectively exceeding 100%and 40%of their initial values,while PETMP-cured products exhibited a complete loss of both tensile strength and adhesion strength.This study provides a strategy for obtaining thermosetting polymers that can be cured at low temperatures and exhibit excellent comprehensive properties. 展开更多
关键词 THIOL epoxy thermosetting polymer Low-temperature curing Heat resistance Chemical resistance Hygrothermal resistance
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Research Study on Intoxication-Efficacy of Raj Yoga Meditation
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作者 Shweta Choudhary Pratap Midha Banarsilal Sah 《Journalism and Mass Communication》 2025年第2期89-97,共9页
Retrospective study of 3,60916 person who were depend on Alcohol and tobacco.In this study we found the result of efficacy of rajyoga meditation very impressive.In this protocol we used early morning meditation,evenin... Retrospective study of 3,60916 person who were depend on Alcohol and tobacco.In this study we found the result of efficacy of rajyoga meditation very impressive.In this protocol we used early morning meditation,evening meditation before sleep,positive affirmation to mind,regular Murli class,traffic control l3-4 times for 3 minutes.(control and remove negative thoughts),charging water and natural cure medicine for de-addiction.The purpose of this study,the effective ness of spiritual oriented lyfe style for natural cure of physically and mentally. 展开更多
关键词 Rajyoga meditation INTOXICATION natural cure medicine charging water Murli class inspiration for optimistic life style
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Effect of magnesium slag and blast furnace slag as partial cement substitutes on properties of cemented tailings backfill
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作者 YANG Jian YANG Xiao-bing +3 位作者 YAN Ze-peng YIN Sheng-hua ZHANG Xi-zhi QI Yao-bin 《Journal of Central South University》 2025年第7期2696-2716,共21页
Utilizing mine solid waste as a partial cement substitute(CS)to develop new cementitious materials is a significant technological innovation that will decrease the expenses associated with filling mining.To realize th... Utilizing mine solid waste as a partial cement substitute(CS)to develop new cementitious materials is a significant technological innovation that will decrease the expenses associated with filling mining.To realize the resource utilization of magnesium slag(MS)and blast furnace slag(BFS),the effects of different contents of MS and BFS as partial CSs on the deformation and energy characteristics of cemented tailings backfill on different curing ages(3,7,and 28 d)were discussed.Meanwhile,the destabilization failure energy criterion of the backfill was established from the direction of energy change.The results show that the strength of all backfills increased with increasing curing age,and the strengths of the backfills exceeded 1.342 MPa on day 28.The backfill with 50%BFS+50%cement has the best performance in mechanical properties(the maximum strength can reach 6.129 MPa)and is the best choice among these CS combinations.The trend in peak strain and elastic modulus of the backfill with increasing curing age may vary depending on the CS combination.The energy index at peak stress of the backfill with BFS as a partial CS was significantly higher than that of the backfill under other CS combinations.In contrast,the enhancement of the energy index when MS was used as a partial CS was not as significant as BFS.Sharp changes in the energy consumption ratio after continuous smooth changes can be used as a criterion for destabilization and failure of the backfill.The research results can provide guidance for the application of MS and BFS as partial CSs in mine filling. 展开更多
关键词 cemented tailings backfill cement substitute curing age mechanical properties energy evolution energy consumption ratio
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Dimensional Effects in CO_(2) Uptake and Compressive Strength of Pervious Concrete Subjected to CO_(2) Curing
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作者 ZHOU Wenjia LIU Lixi +3 位作者 ZHU Liangliang WANG Keying XIAO Hang CHEN Xi 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期728-740,共13页
The size effects were experimentally investigated and the underlying mechanism was analyzed.The results reveal that,as the specimen size increases,the interconnectivity of macropores slightly decreases.This in turn co... The size effects were experimentally investigated and the underlying mechanism was analyzed.The results reveal that,as the specimen size increases,the interconnectivity of macropores slightly decreases.This in turn constrains the diffusion of CO_(2) and moisture in the specimens,resulting in an increase in the discrepancy between the internal and external carbonation degrees.An increase in cement paste thickness simultaneously decreases the quantity,average size,and interconnectivity of macropores,lowering the diffusion efficacy of CO_(2) and moisture and exacerbating the overall heterogeneity in carbonation.Moreover,the gradual blockage of macropores leads to the emergence of localized ‘occluded zones’ with much lower carbonation degree.The reduction in aggregate size significantly alters the average diameter and connectivity of macropores,leading to notable change to overall non-uniformity.This study provides insight into improving the CO_(2) curing effect of pervious concrete products and developing uniform curing methods. 展开更多
关键词 carbonation curing pervious concrete dimensional effects CO_(2)uptake
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CO_(2)mineralization curing steel slag-fly ash-Portland cement ternary paste:Mechanical properties,microstructure and life cycle assessment
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作者 YI Guo-yang TIAN Wei +2 位作者 SHI Jun-jie GUO Jian CHENG Xu 《Journal of Central South University》 2025年第7期2487-2510,共24页
Using solid waste as a substitute for conventional cement has become an important way to reduce carbon emissions.This paper attempted to utilize steel slag(SS)and fly ash(FA)as supplementary cementitious material by u... Using solid waste as a substitute for conventional cement has become an important way to reduce carbon emissions.This paper attempted to utilize steel slag(SS)and fly ash(FA)as supplementary cementitious material by utilizing CO_(2)mineralization curing technology.This study examined the dominant and interactive influences of the residual water/cement ratio,CO_(2)pressure,curing time,and SS content on the mechanical properties and CO_(2)uptake rate of CO_(2)mineralization curing SS-FA-Portland cement ternary paste specimens.Additionally,microstructural development was analyzed.The findings demonstrated that each factor significantly affected compressive strength and CO_(2)uptake rate,with factor interactions becoming more pronounced at higher SS dosages(>30%),lower residual water/cement ratios(0.1-0.15),and CO_(2)pressures of 0.1-0.3 MPa.Microscopic examinations revealed that mineralization primarily yielded CaCO_(3)and silica gel.The residual w/c ratio and SS content significantly influenced the CaCO_(3)content and crystallinity of the mineralization products.Post-mineralization curing,the percentage of pores larger than 50 nm significantly decreased,the proportion of harmless pores smaller than 20 nm increased,and pore structure improved.This study also found that using CO_(2)mineralization curing SS-FA-Portland cement solid waste concrete can significantly reduce the negative impact on the environment. 展开更多
关键词 ternary paste CO_(2)curing response surface methodology life cycle assessment
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Performance and Characterization of Fluidized Solidified Soil Prepared by Synergistic Cement and Phosphogypsum with Slag Powder-Fly Ash
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作者 CHEN Shujie FENG Chao +6 位作者 FU Tengfei YU Demei ZHANG Hengchun ZHANG Feng WANG Yao HUANG Xia WANG Yulin 《Journal of Wuhan University of Technology(Materials Science)》 2025年第5期1320-1329,共10页
Fluidized solidified soil(FSS)is an innovative backfill material that offers benefits such as easy pumping and straightforward construction.This study examined how varying the water-soil ratio and the curing agent dos... Fluidized solidified soil(FSS)is an innovative backfill material that offers benefits such as easy pumping and straightforward construction.This study examined how varying the water-soil ratio and the curing agent dosage affect the properties and microstructure of FSS.The strength development mechanism was investigated when composite solidification agents were used.The findings show that both the water-solid ratio and the curing agent dosage can affect the microstructure of FSS,thereby affecting its performance.When the water-solid ratio increases from 0.52 to 0.56,the unconfined compressive strength(UCS)and flexural strength of the FSS decrease by 34.1% and 39.3% after 28 d.Conversely,the curing agent dosage increasing from 10% to 30% will increase both UCS and flexural strength by 11.2 times and 11.1 times.As the curing age increases,the number of cracks at failure point in the FSS will increase and lead to a more complete failure.Numerous needle-like AFt,C-S-H gel,and C-(A)-S-H gel create a three-dimensional network by adhering to soil particles. 展开更多
关键词 fluidized solidified soil water-solid ratio curing agent dosage maintenance age microscopic analysis:mechanism of strength formation
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