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Valuable clinical indicators for identifying infantile-onset inflammatory bowel disease patients with monogenic diseases 被引量:5
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作者 Wen Su yi yu +4 位作者 Xu Xu Xin-Qiong Wang Jie-Bin Huang Chun-Di Xu yuan Xiao 《World Journal of Gastroenterology》 SCIE CAS 2021年第1期92-106,共15页
BACKGROUND Infantile-onset inflammatory bowel disease(IO-IBD)occurs in very young children and causes severe clinical manifestations,which has poor responses to traditional inflammatory bowel disease(IBD)treatments.At... BACKGROUND Infantile-onset inflammatory bowel disease(IO-IBD)occurs in very young children and causes severe clinical manifestations,which has poor responses to traditional inflammatory bowel disease(IBD)treatments.At present,there are no simple and reliable laboratory indicators for early screening IO-IBD patients,especially those in whom the disease is caused by monogenic diseases.AIM To search for valuable indicators for early identifying IO-IBD patients,especially those in whom the disease is caused by monogenic diseases.METHODS A retrospective analysis was performed in 73 patients with IO-IBD admitted to our hospital in the past 5 years.Based on the next-generation sequencing results,they were divided into a monogenic IBD group(M-IBD)and a non-monogenic IBD group(NM-IBD).Forty age-matched patients with allergic proctocolitis(AP)were included in a control group.The clinical manifestations and the inflammatory factors in peripheral blood were evaluated.Logistic regression analysis and receiver operating characteristic(ROC)curve analysis were used to identify the screening factors and cut-off values of IO-IBD as well as monogenic IO-IBD,respectively.RESULTS Among the 44 M-IBD patients,35 carried IL-10RA mutations,and the most common mutations were c.301C>T(p.R101W,30/70)and the c.537G>A(p.T179T,17/70).Patients with higher serum tumor necrosis factor(TNF)-αvalue were more likely to have IBD[odds ratio(OR)=1.25,95%confidence interval(CI):1.05-1.50,P=0.013],while higher serum albumin level was associated with lower risk of IBD(OR=0.86,95%CI:0.74-1.00,P=0.048).The cut-off values of TNF-αand albumin were 17.40 pg/mL(sensitivity:0.78;specificity:0.88)and 36.50 g/L(sensitivity:0.80;specificity:0.90),respectively.The increased ferritin level was indicative of a genetic mutation in IO-IBD patients.Its cut-off value was 28.20 ng/mL(sensitivity:0.93;specificity:0.92).When interleukin(IL)-10 level was higher than 33.05 pg/mL(sensitivity:1.00;specificity:0.84),or the onset age was earlier than 0.21 mo(sensitivity:0.82;specificity:0.94),the presence of diseasecausing mutations in IL-10RA in IO-IBD patients was strongly suggested.CONCLUSION Serum TNF-αand albumin level could differentiate IO-IBD patients from allergic proctocolitis patients,and serum ferritin and IL-10 levels are useful indicators for early diagnosing monogenic IO-IBD. 展开更多
关键词 Infantile-onset inflammatory bowel disease IMMUNODEFICIENCY Clinical indicators Interleukin 10 FERRITIN IL10RA
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基于Delta影像组学构建筋骨通络颗粒对急性外踝韧带损伤修复疗效的预测模型
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作者 陈天鑫 吴俊莹 +5 位作者 韩庆欣 于美琪 易宇 李妍 刘晓华 张磊 《中国中药杂志》 北大核心 2025年第17期4982-4989,共8页
筋骨通络颗粒治疗急性外踝韧带损伤疗效显著,然而其临床疗效精准评估存在困难,故基于Delta影像组学,建立筋骨通络颗粒治疗急性外踝韧带损伤的机器学习疗效预测模型。该研究纳入经保护、适当负重、冰敷、加压包扎、抬高患肢(POLICE)原则... 筋骨通络颗粒治疗急性外踝韧带损伤疗效显著,然而其临床疗效精准评估存在困难,故基于Delta影像组学,建立筋骨通络颗粒治疗急性外踝韧带损伤的机器学习疗效预测模型。该研究纳入经保护、适当负重、冰敷、加压包扎、抬高患肢(POLICE)原则联合筋骨通络颗粒外用治疗2周的急性距腓前韧带损伤患者107例,根据美国足踝协会评分分为疗效优良组(71例)和疗效欠佳组(36例),并按7∶3分为训练集、验证集。提取并筛选治疗前后横轴位踝关节磁共振成像中与距腓前韧带损伤高度相关的影像组学特征。采用轻量级梯度提升机(LightGBM)机器学习分类器,分别构建治疗前、后以及Delta影像组学模型。通过受试者工作特征曲线(ROC)、决策曲线分析(DCA)和校准曲线,对各模型的临床实用性与预测效能进行评估。共获取到1197个影像组学特征,经过特征筛选和降维,分别保留治疗前、后以及Delta影像组学特征4、13、8个,采用Light-GBM建立机器学习模型。基于Delta影像特征建立的LightGBM模型预测效能最佳,在训练集和验证集的AUC分别为0.917(95%CI[0.856,0.979])、0.863(95%CI[0.729,0.998]),且DCA、校准曲线均显示预测效能良好。基于Delta影像组学建立的LightGBM机器学习模型,对预测筋骨通络颗粒治疗急性距腓前韧带损伤的修复疗效具有良好效能。 展开更多
关键词 距腓前韧带损伤 筋骨通络颗粒 Delta影像组学 机器学习 临床疗效
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Constrained Networked Predictive Control for Nonlinear Systems Using a High-Order Fully Actuated System Approach 被引量:1
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作者 yi Huang Guo-Ping Liu +1 位作者 yi yu Wenshan Hu 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期478-480,共3页
Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectiv... Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectively deal with nonlinearities,constraints,and noises in the system,optimize the performance metric,and present an upper bound on the stable output of the system. 展开更多
关键词 optimal control problem constrained networked predictive control strategy Performance Optimization present upper bound Nonlinear Systems NOISES Constrained Networked Predictive Control High Order Fully Actuated Systems
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Effects of acupuncture needle modification on acupuncture analgesia 被引量:1
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作者 Ming-zhu Sun Xin Wang +5 位作者 ying-chen Li yu-hang Liu yi yu Liu-jie Ren Wei Gu Wei Yao 《Journal of Integrative Medicine》 2025年第1期66-78,共13页
Objective The analgesic effect of acupuncture has been widely accepted.Nevertheless,the mechanism behind its analgesic effect remains elusive,thus impeding the progress of research geared toward enhancing the analgesi... Objective The analgesic effect of acupuncture has been widely accepted.Nevertheless,the mechanism behind its analgesic effect remains elusive,thus impeding the progress of research geared toward enhancing the analgesic effect of acupuncture.This paper investigated the role of acupuncture needle surface textures on acupuncture’s analgesic effect by creating four experimental acupuncture needles with different patterns of surface augmentation.Methods Four types of acupuncture needles with different surface textures(the lined needle,circle needle,sandpaper needle,and threaded needle)were designed.Additionally,the force/torque measurement system used a robot arm and mechanical sensor to measure the force on the needle during insertion and manipulation.To perform acupuncture analgesia experiments,four experimental acupuncture needles and a normal needle were inserted into the Zusanli(ST36)acupoint of rats with inflammatory pain.By comparing the force and torque and the analgesic efficacy of the different acupuncture needles,these experiments tested the role of acupuncture needle body texture on acupuncture analgesia.Results The analgesic effects of different acupuncture needle body textures varied.Specifically,the force required to penetrate the skin with the lined needle was not greater than that for the normal needle;however,the needle with inscribed circles and the sandpaper-roughened needle both required greater force for insertion.Additionally,the torque of the lined needle reached 2×10^(-4)N·m under twisting manipulation,which was four times greater the torque of a normal needle(5×10^(-5)N·m).Furthermore,the lined needle improved pain threshold and mast cell degranulation rate compared to the normal needle.Conclusion Optimizing the texture of acupuncture needles can enhance acupuncture analgesia.The texture of our experimental acupuncture needles had a significant impact on the force needed to penetrate the skin and the torque needed to manipulate the needle;it was also linked to variable analgesic effects.This study provides a theoretical basis for enhancing the analgesic efficacy of acupuncture through the modification of needles and promoting the development of acupuncture therapy. 展开更多
关键词 Acupuncture needle Acupuncture needle modification Analgesic efficacy Pain threshold Mast cell degranulation
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ZnO/PI复合薄膜的制备及电气特性表征
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作者 张朋飞 张保康 +2 位作者 张玉苹 易羽 王一帆 《塑料》 北大核心 2025年第1期58-62,80,共6页
聚酰亚胺(PI)由于其较好的物理与化学性能在绝缘质材料领域得到广泛关注,在电子器件封装、航空航天领域及电力电缆中已得到规模化应用。为了提高复合绝缘材料的电气特性及应用价值,并开发聚酰亚胺的改性方法,先利用仿真方法得到电缆绝... 聚酰亚胺(PI)由于其较好的物理与化学性能在绝缘质材料领域得到广泛关注,在电子器件封装、航空航天领域及电力电缆中已得到规模化应用。为了提高复合绝缘材料的电气特性及应用价值,并开发聚酰亚胺的改性方法,先利用仿真方法得到电缆绝缘材料改性后电场分布的优化效果,再通过改变氧化锌(ZnO)纳米颗粒质量分数制备出不同掺杂量的ZnO/PI复合薄膜进行实验验证,最后,对复合材料的电气特性进行深入研究。结果表明,当ZnO的质量分数为1.5%时,ZnO/PI复合薄膜的击穿场强较高,与纯PI薄膜相比,约提升了20%,证明了ZnO纳米颗粒可以实现在低添加量下显著提升复合薄膜的击穿场强。 展开更多
关键词 聚酰亚胺 纳米ZNO 介电常数 击穿性能 电场仿真
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金枪鱼眼透明质酸的提取工艺研究 被引量:6
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作者 易喻 徐骏 +4 位作者 梅建凤 陈建澍 张彦璐 龚海平 应国清 《浙江工业大学学报》 CAS 北大核心 2018年第3期276-281,共6页
首次从金枪鱼眼中提取透明质酸(Hyaluronic acid,HA)并进行工艺优化,以获取安全、廉价的透明质酸.采用季铵盐络合法纯化透明质酸,以透明质酸的质量分数、回收率、蛋白质量分数为指标,考查反应时间、物料比、盐离子浓度等因素的影响,并... 首次从金枪鱼眼中提取透明质酸(Hyaluronic acid,HA)并进行工艺优化,以获取安全、廉价的透明质酸.采用季铵盐络合法纯化透明质酸,以透明质酸的质量分数、回收率、蛋白质量分数为指标,考查反应时间、物料比、盐离子浓度等因素的影响,并与离子交换法纯化透明质酸作比较.结果表明:反应时间为60min,料液比为25∶2,络合反应NaCl浓度为0.2mol/L,解离时NaCl浓度为0.4mol/L为最佳条件,最终透明质酸回收率91.3%,质量分数90.1%,蛋白质量分数0.1%.离子交换法所得透明质酸回收率74.3%,HA质量分数92.2%,蛋白质量分数0.1%.优化后的工艺路线在透明质酸回收率、生产成本上更有优势,为金枪鱼眼透明质酸提取利用提供了应用基础. 展开更多
关键词 透明质酸 工艺优化 十六烷基氯化吡啶 金枪鱼眼
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施磷增氧条件对水稻光合特性及镉吸收分配的影响 被引量:3
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作者 张文萍 管啸 +5 位作者 钟诚 易宇 肖卫华 易达理 杨良玖 吴根义 《农业环境科学学报》 CAS CSCD 北大核心 2022年第9期1875-1886,共12页
为探明水稻镉吸收及叶片光合特性对增氧条件下施磷量的响应特征,明确施磷量和根际增氧的作用效果,以杂交水稻C两优608为材料,考虑施磷水平和灌溉方式两个主要因素,设置4个施磷(PO)水平,即P1(不施磷)、P2(0.18 g·kg^(-1))、P3(0.36 ... 为探明水稻镉吸收及叶片光合特性对增氧条件下施磷量的响应特征,明确施磷量和根际增氧的作用效果,以杂交水稻C两优608为材料,考虑施磷水平和灌溉方式两个主要因素,设置4个施磷(PO)水平,即P1(不施磷)、P2(0.18 g·kg^(-1))、P3(0.36 g·kg^(-1))、P4(0.54 g·kg^(-1)),2种灌溉方式,即NI(不增氧灌溉)、OI(增氧灌溉),采用盆栽试验研究施磷与增氧对水稻各生育期叶片光合特性及成熟期镉吸收及迁移转运的影响规律,确定了水稻叶片光合特性与水稻镉吸收的对应关系,揭示了施磷与增氧降低水稻成熟期籽粒镉含量的机理。结果表明:与不施磷相比,无论增氧与否,施磷均可促进水稻成熟期根部、秸秆部镉的吸收与转运;增氧处理下水稻镉由秸秆部向籽粒的转运系数、籽粒镉累积分配比例均低于不增氧处理,秸秆部镉累积分配比例均高于不增氧处理;不外施磷肥情况下,增氧处理水稻成熟期籽粒镉含量最低(0.13 mg·kg^(-1)),水稻各部位镉多集中于根部(33.95%)和秸秆部(46.18%),只有19.87%集中于籽粒。抽穗期、灌浆期是影响水稻成熟期镉吸收的关键时期,增氧在提高灌浆期净光合能力的同时,还促进了镉由水稻根部向秸秆部转移,降低了镉从秸秆部向籽粒的转移,使水稻镉进行重新分配。研究表明,增氧可通过调整水稻内在敏感性,降低水稻成熟期籽粒镉含量及镉从秸秆部向籽粒的转移能力。 展开更多
关键词 叶片光合特性 镉吸收 施磷 增氧灌溉 氧磷互作 水稻
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Robot-assisted percutaneous coronary intervention:a prospective,multicenter,randomized controlled,non-inferiority clinical trial
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作者 yi yu Zheng CHEN +7 位作者 Zhi-Jian WANG yue-Ping LI Li-Xia YANG Jing QI Jing XIE Tao HUANG Dong-Mei SHI yu-Jie ZHOU 《Journal of Geriatric Cardiology》 2025年第8期725-735,共11页
OBJECTIVE To evaluate the safety and effectiveness of robot-assisted percutaneous coronary intervention(R-PCI)compared to traditional manual percutaneous coronary intervention(M-PCI).METHODS This prospective,multicent... OBJECTIVE To evaluate the safety and effectiveness of robot-assisted percutaneous coronary intervention(R-PCI)compared to traditional manual percutaneous coronary intervention(M-PCI).METHODS This prospective,multicenter,randomized controlled,non-inferior clinical trial enrolled patients with coronary heart disease who met the inclusion criteria and had indications for elective percutaneous coronary intervention.Participants were randomly assigned to either the R-PCI group or the M-PCI group.Primary endpoints were clinical and technical success rates.Clinical success was defined as visually estimated residual post-percutaneous coronary intervention stenosis<30% with no 30-day major adverse cardiac events.Technical success in the R-PCI group was defined as successful completion of percutaneous coronary intervention using the ETcath200 robot-assisted system,without conversion to M-PCI in the event of a guidewire or balloon/stent catheter that was unable to cross the vessel or was poorly supported by the catheter.Secondary endpoints included total procedure time,percutaneous coronary intervention procedure time,fluoroscopy time,contrast volume,operator radiation exposure,air kerma,and dose-area product.RESULTS The trial enrolled 152 patients(R-PCI:73 patients,M-PCI:79 patients).Lesions were predominantly B2/C type(73.6%).Both groups achieved 100% clinical success rate.No major adverse cardiac events occurred during the 30-day follow-up.The R-PCI group had a technical success rate of 100%.The R-PCI group had longer total procedure and fluoroscopy times,but lower operator radiation exposure.The percutaneous coronary intervention procedure time,contrast volume,air kerma,and dose-area product were similar between the two groups.CONCLUSIONS For certain complex lesions,performing percutaneous coronary intervention using the ETcath200 robot-assisted system is safe and effective and does not result in conversion to M-PCI. 展开更多
关键词 complex lesions non inferiority clinical trial technical success operator radiation exposure robot assisted percutaneous coronary intervention coronary heart disease elective percutaneous coronary interventionparticipants traditional manual percutaneous coronary intervention m pci methods
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黏质沙雷氏菌发酵制备舍雷肽酶及基本酶学性质研究 被引量:3
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作者 梅建凤 李靓 +2 位作者 唐国强 易喻 应国清 《中国药学杂志》 CAS CSCD 北大核心 2020年第24期2057-2062,共6页
目的开发微生物发酵生产舍雷肽酶的工艺,并了解基本酶学特性。方法从家蚕蛹的肠道中分离产酶菌株,单因素实验和响应面实验优化发酵培养基,采用(NH4)2SO4沉淀、超滤和DEAE离子交换层析3步纯化舍雷肽酶,电泳法测定酶的相对分子质量和等电... 目的开发微生物发酵生产舍雷肽酶的工艺,并了解基本酶学特性。方法从家蚕蛹的肠道中分离产酶菌株,单因素实验和响应面实验优化发酵培养基,采用(NH4)2SO4沉淀、超滤和DEAE离子交换层析3步纯化舍雷肽酶,电泳法测定酶的相对分子质量和等电点,考察pH和温度对酶活力和稳定性的影响,并测算酶的反应动力学常数。结果分离获得一株产舍雷肽酶的黏质沙雷氏菌LL-413菌株,摇瓶发酵产酶活力达到1 126 U·mL^-1,10-L发酵罐中发酵产酶活性达到1 505 U·mL^-1;舍雷肽酶相对分子质量和等电点分别约为52×103和7.2;酶活最适pH为8.0,在pH 5.0~10.0之间稳定;酶活最适温度为40℃,在45℃以下稳定。以酪蛋白为底物时,米氏常数(Km)和最大反应速度(Vmax)分别为22.3 mg·mL^-1和1 355 mg·L·min^-1。结论利用黏质沙雷氏菌LL-413菌株生产舍雷肽酶发酵单位高,酶的蛋白水解能力强、pH和热稳定性好,研究结果为该酶的生产和应用奠定了基础。 展开更多
关键词 舍雷肽酶 黏质沙雷氏菌 酶的分离和纯化 酶学特性
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Insight into the efficacy and safety of pirfenidone: The treatment of idiopathic pulmonary fibrosis
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作者 Li-ying Xu yi yu Lu-Sha Cen 《World Journal of Clinical Cases》 2025年第14期58-60,共3页
Idiopathic pulmonary fibrosis(IPF)has a poor prognosis if left untreated;therefore,early treatment with pirfenidone is crucial.Lei et al conducted a retrospective analysis to evaluate the effectiveness of early pirfen... Idiopathic pulmonary fibrosis(IPF)has a poor prognosis if left untreated;therefore,early treatment with pirfenidone is crucial.Lei et al conducted a retrospective analysis to evaluate the effectiveness of early pirfenidone treatment on lung function in 113 patients with IPF.In addition to other research,pirfeni-done has demonstrated efficacy in patients at all stages of IPF once correct diagnosis has been made.In advanced IPF,we include the requirement for pirfenidone.Therefore,it is essential to choose an appropriate method of adminis-tration method,such as inhalation.This may circumvent the drawbacks of the high cost and possible adverse effects of this drug. 展开更多
关键词 Pirfenidone Idiopathic pulmonary fibrosis Route of administration Dia-gnose Early treatment Alternative formulations
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Mitigating drought-associated reproductive failure in maize:From physiological mechanisms to practical solutions
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作者 Zhiwei Wang yi yu +5 位作者 Xiang Chen Yangyang Li Ashley Jones Ray J.Rose Yong-Ling Ruan Youhong Song 《The Crop Journal》 2025年第4期1022-1031,共10页
Maize serves as a crucial cereal crop globally,yet the escalating frequency of drought stress during the reproductive phase poses a significant threat to grain yield by causing an irreversible loss in kernel number.En... Maize serves as a crucial cereal crop globally,yet the escalating frequency of drought stress during the reproductive phase poses a significant threat to grain yield by causing an irreversible loss in kernel number.Enhancing reproductive drought tolerance in maize requires elucidating the physiological mechanisms underlying its response to drought stress,which can then be incorporated into the development of new maize varieties through breeding programs.Additionally,innovative cultivation practices must be devised to complement these genetic improvements.In this review,the timing,duration,and severity of drought stress during the reproductive stage and their effects on maize kernel set are assessed,providing a basis for constructing a framework that links kernel setting to drought stress.Based on this framework,reproductive drought tolerance from tasseling through post-fertilization kernel establishment is subsequently examined.Evidence indicates that drought-induced fertilization failure is primarily due to delayed pollination resulting from slower silk elongation,which is caused by the loss of cell turgor and reduced carbon supply.Meanwhile,kernel abortion after fertilization is mainly triggered by carbohydrate starvation,increased ethylene emission,and the accumulation of abscisic acid(ABA).Therefore,sugar metabolism,hydraulic status,and hormone signaling collectively regulate maize's kernel setting tolerance to drought stress in a synergistic manner.Several novel gene candidates with potential for conferring drought tolerance in maize have been identified,offering promising targets for genetic improvement through genome editing combined with targeted cultivation practices to enhance maize drought tolerance and ensure stable grain yield in future crops. 展开更多
关键词 Zea mays L. Drought stress Kernel set Reproductive failure Sugar starvation Grain yield
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Interfacial Elastic Film with Temperature Mediated-phase Transition Behavior for Tunable Suspended Sensing
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作者 Wei Zhou yue Han +3 位作者 Peng Xiao yi yu yu-Chao Wang Tao Chen 《Chinese Journal of Polymer Science》 2025年第7期1155-1162,共8页
Controllably tuning the sensing performance of flexible mechanical sensors is important for them to realize on-demand sensing of various mechanical stimuli in different application scenarios.However,current regulating... Controllably tuning the sensing performance of flexible mechanical sensors is important for them to realize on-demand sensing of various mechanical stimuli in different application scenarios.However,current regulating strategies focus on the construction process of individual sensors,the response performance of the as-formed sensors is still hard to autonomously tune with external stimulus changes like human skin.Here,we propose a new strategy that realizes post-tuning of the sensing performance by introducing a temperature-dependent phase transition elastomer into the sensing film.Through an interfacially confined photopolymerization reaction,a graphene-based phase-transition elastomeric(GPTE)film with a robust interface and excellent conductivity is well-formed at the water/air interface.Benefiting from the crystallization-melt dynamic switching in the elastomer network,the GPTE film could experience the reversible transformation between soft(1.65 MPa)and stiff(12.27MPa)states,showing huge changes of elastic modulus up to seven times near the phase transition temperature(28.5℃).Furthermore,the GPTE film is designed into a suspended perceptual configuration realizing the dynamic detection of 3D deformation adapted to temperature changes with up to 3.5-fold difference in response sensitivity.Finally,the self-adaptive sensing behavior of temperature-mediated 3D deformation is demonstrated by the effective detection of the dynamic stimulation process of cold and hot water droplets by the GPTE suspended film.The proposed strategy of phase transition-induced post-tuning of sensing performance could greatly facilitate flexible mechanical sensors towards a more intelligent one. 展开更多
关键词 Phase transition elastomer Crystallization-melt switching Tunable modulus Suspended sensor Tunable sensing performance
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Genetic control of cereal kernel texture:Towards a maize model
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作者 Jie Lei yueyue Du +7 位作者 yi yu Yali Yan Xiaoyue Luan Sai Liu Qingwen Shen Hongyu Chen Jihua Tang Guifeng Wang 《The Crop Journal》 2025年第6期1682-1692,共11页
Because cereal kernel texture is a determinant of maize end-use properties,it is desirable to elucidate the genetic control of kernel formation and thereby to optimize maize kernel texture for breeding.Basically,maize... Because cereal kernel texture is a determinant of maize end-use properties,it is desirable to elucidate the genetic control of kernel formation and thereby to optimize maize kernel texture for breeding.Basically,maize kernel texture is determined by the ratio of vitreous endosperm in the peripheral region to the floury endosperm in the center of the kernel.In contrast to the puroindoline proteins(Pins)as the major determinants of grain texture specific to wheat,maize kernel texture is a quantitative trait that is controlled by many minor-effect genes.Nonetheless,substantial progresses have been made in unravelling gene regulatory networks underlying maize kernel formation that is related to its texture.Here,we review the current knowledge on maize endosperm development,focusing on vitreous and floury endosperm formation,and summarize the potential transcription regulatory mechanisms for starch and zein biosynthesis.The integration of the information will potentially provide valuable candidate genes for breeding maize varieties with improved kernel texture and quality. 展开更多
关键词 MAIZE Kernel texture Vitreous and floury endosperm Starch and zein biosynthesis Transcriptional regulatory network
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高产舍雷肽酶的粘质沙雷氏菌诱变选育 被引量:3
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作者 梅建凤 蔡少芬 +2 位作者 李靓 易喻 应国清 《食品与发酵工业》 CAS CSCD 北大核心 2018年第8期177-180,共4页
舍雷肽酶是一种来自粘质沙雷氏菌(Serratia marcescens)的碱性蛋白酶,具有良好的抗炎和抗肿胀作用,应用于临床疾病的治疗已有多年。为了获得产酶活力高、传代稳定且不产灵菌红素的舍雷肽酶发酵生产菌株,以1株分离自家蚕(Bombyx mori)肠... 舍雷肽酶是一种来自粘质沙雷氏菌(Serratia marcescens)的碱性蛋白酶,具有良好的抗炎和抗肿胀作用,应用于临床疾病的治疗已有多年。为了获得产酶活力高、传代稳定且不产灵菌红素的舍雷肽酶发酵生产菌株,以1株分离自家蚕(Bombyx mori)肠道,产舍雷肽酶的粘质沙雷氏菌LL-413为出发菌株,用紫外线和微波连续诱变,经过筛选,获得了2株产酶能力高,不产灵菌红素,且传代稳定的突变株MW-9和MW-14菌株,产酶活力分别达到982 U/mL和956 U/mL,是原始菌株的1.98倍和1.92倍。 展开更多
关键词 舍雷肽酶 粘质沙雷氏菌 诱变育种 紫外线 微波
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Effect of Grifola frondosa polysaccharide on immune function and gut microbiota in mice
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作者 Linlin Ma Xiaoliang Lin +5 位作者 Ming Liang Jieyi Long Xian Qu yi yu yifa Zhou Hairong Cheng 《Acupuncture and Herbal Medicine》 2025年第1期68-75,共8页
Objective:Grifola frondosa,a medicinal mushroom,is widely used to enhance immunity and treat cancer.Polysaccharides are its primary active components.We aimed to investigate the effects of the alkaloid G.frondosa poly... Objective:Grifola frondosa,a medicinal mushroom,is widely used to enhance immunity and treat cancer.Polysaccharides are its primary active components.We aimed to investigate the effects of the alkaloid G.frondosa polysaccharide(GFP)extract on immunity and gut microbiota.Methods:Alkaloid GFP was extracted using an alkaline extraction method,followed by hollow-fiber microfiltration.The molecular weight of alkaloid GFP was determined by high-performance gel permeation chromatography(HPGPC).Monosaccharide composition was analyzed by pre-column derivatization combined with high-performance liquid chromatography(HPLC).Methylation analysis was performed to characterize glycosidic linkages in alkaloid GFP.The immune function of alkaloid GFP was assessed in a cyclophosphamide(CTX)-induced immunosuppressive mouse model.Splenic lymphocyte proliferation,macrophage phagocytic capacity,and natural killer(NK)cell cytotoxicity were evaluated.The effect of alkaloid GFP on gut microbiota was assessed by 16S rRNA sequencing.Results:The molecular weight distribution of alkaloid GFP ranged from 17 to 18 kDa.The alkaloid GFP contained aβ-(1→6)-glucan backbone branched at O-3 byβ-1,3-D-Glcp.Oral administration of alkaloid GFP mitigated the effects of CTX on spleen index,splenic lymphocyte proliferation,and peritoneal macrophage phagocytosis.Additionally,alkaloid GFP improved the gut microbiota composition of immunosuppressed mice,increasing the relative abundances of Ligilactobacillus and Lactobacillus.Conclusions:Alkaloid GFP demonstrated immune-enhancing effects and gut microbiota regulatory activity,providing a basis for developing related health food ingredients. 展开更多
关键词 Grifola frondosa Gut microbiota Immune activity POLYSACCHARIDE
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真空回转保湿制氮技术在高大平房仓稻谷储藏中防虫应用的研究
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作者 伊瑜 张强 +2 位作者 黄超 刘勇 李天阳 《粮油科学与工程》 2025年第4期7-11,共5页
以经气密性升级改造后的高大平房仓为储粮设施,研究真空回转保湿制氮技术的防虫功效。结果表明:真空回转保湿制氮设备输出压力25 kPa以下时,保湿氮气最大流量可达400 m3/h,输出保湿氮气最大浓度可达99.8%以上;设备运行35 h可达到低氧杀... 以经气密性升级改造后的高大平房仓为储粮设施,研究真空回转保湿制氮技术的防虫功效。结果表明:真空回转保湿制氮设备输出压力25 kPa以下时,保湿氮气最大流量可达400 m3/h,输出保湿氮气最大浓度可达99.8%以上;设备运行35 h可达到低氧杀虫浓度(小于2%),低氧维持28 d以上害虫死亡率100%,杀虫效果显著;充氮杀虫全周期能耗仅有1.01 kW·h/t,节能效果显著;充氮防虫不仅对米饭食味评分无显著不良影响,而且对稻谷脂肪酸值的上升有一定抑制作用,缓解稻谷陈化进程;保湿制氮技术还减少了粮食储存期间的水分散失。 展开更多
关键词 氮气气调 真空回转保湿制氮 常压 高大平房仓
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Regulating degradation in MgZnCa metallic glass:Formation of zinc-rich amorphous layer through internal zinc migration
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作者 yi yu yuantao Shi +2 位作者 Cheng Zhang Lin Liu Jie Pan 《Journal of Magnesium and Alloys》 2025年第7期3346-3356,共11页
Advancing biodegradable medical implants,along with an in-depth understanding of their degradation mechanisms,is critical to revolutionizing orthopedic medicine and improving patient outcomes.MgZnCa metallic glass(MG)... Advancing biodegradable medical implants,along with an in-depth understanding of their degradation mechanisms,is critical to revolutionizing orthopedic medicine and improving patient outcomes.MgZnCa metallic glass(MG)stands out among degradable metallic materials due to its superior potential for orthopedic applications than traditional crystalline alloys.Despite its advantages,there has been a lack of comprehensive insight into the degradation behavior of MgZnCa MG,particularly under conditions simulating daily activities of patients.In this work,the degradation mechanism of MgZnCa MG is elucidated,highlighting the formation of a distinctive Zn-rich amorphous layer that markedly decelerates the matrix degradation.Detailed analysis reveals that the unique amorphous structure of MgZnCa MG facilitates the selective dissolution of Mg and Ca,resulting in numerous vacancies within the matrix.These vacancies facilitate the inward migration of Zn atoms,culminating in the formation of a dense Zn-rich layer.This cyclical formation and dissolution of the Zn-rich layer serve as a buffer in the degradation pathway,thus ensuring a degradation rate for MgZnCa MG that is significantly slower than that of its crystalline counterparts. 展开更多
关键词 MgZnCa metallic glass Dynamic degradation Hierarchical corrosion structure Zn-rich layer
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超大规模教育空间中的高效组织与人文关怀——深圳中学高中园
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作者 刘杨洋 易豫 孟建民 《当代建筑》 2025年第6期86-95,共10页
在深圳中学高中园项目中,设计团队对超大规模校园高效组织与人文关怀融合的路径进行了探索。设计通过组团式规划、一园三校的功能布局,以及多维高效的交通联系,实现了对万人规模校园的高效协同。同时,设计结合岭南文化进行现代诠释,因... 在深圳中学高中园项目中,设计团队对超大规模校园高效组织与人文关怀融合的路径进行了探索。设计通过组团式规划、一园三校的功能布局,以及多维高效的交通联系,实现了对万人规模校园的高效协同。同时,设计结合岭南文化进行现代诠释,因地制宜地营造低碳生态校园,为师生提供健康舒适、富有文化内涵的学习生活场所。 展开更多
关键词 教育建筑 超大规模校园设计 本原设计
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Analysis of the distribution of sound velocity profiles and sound propagation laws based on a global high-resolution ocean reanalysis product
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作者 Shiyuan Tao yi yu +2 位作者 Wenbin Xiao Weimin Zhang Yanlai Zhao 《Acta Oceanologica Sinica》 2025年第5期131-149,共19页
Ocean reanalysis data,compared to traditional observational data,possess stronger continuity and higher data accuracy.The globally high-resolution ice-ocean coupled reanalysis product China Ocean ReAnalysis,Version 2.... Ocean reanalysis data,compared to traditional observational data,possess stronger continuity and higher data accuracy.The globally high-resolution ice-ocean coupled reanalysis product China Ocean ReAnalysis,Version 2.0(CORA v2.0),independently developed by the National Marine Information Center,has attracted considerable attention since its release in 2020.This study selected six representative points of sound velocity profiles in different global ocean regions and conducted comparative analysis between the 2014 momentary data from CORA v2.0 and Argo data.Additionally,the monthly average data of CORA v2.0 in 2013 were compared and studied against General Digital Environmental Model(GDEM)and World Ocean Atlas(WOA)data.Metrics such as Root Mean Square Error(RMSE)and Mean Error(ME)were introduced to evaluate the differences between datasets.The result reveals that,in a comparison of single moment data,the sound velocity profiles of CORA v2.0 data and Argo data exhibit high consistency,with ME generally within 2 m/s.Regarding a comparison of monthly average data,the consistency between CORA v2.0 data and WOA data is higher,while the error relative to GDEM data is relatively larger,but their RMSE and ME exhibit high similarity in temporal trends.Based on the 2014 data of CORA v2.0,the temporal and spatial evolutionary laws of global seawater sound velocity profiles and sound speed fields were analyzed.On the time scale,the variation of seawater sound speed is mainly influenced by seasons,with significant differences between winter and summer seasons.On the daily scale,there are certain differences in sound velocity profiles mainly in the early morning and afternoon.On the spatial scale,analysis was conducted from both horizontal and vertical perspectives.The distribution of sound speed exhibits evident regularity with latitude,with shallow seawater sound speed being greatly influenced by external factors while deep seawater is relatively stable.Using the Range-dependent Acoustic Model for Geoacoustics(RAMgeo)model to solve the underwater acoustic field at three specific points,the characteristic changes of sound velocity profiles at different times of the day and their impact on under water sound propagation losses were obtained.This paper provides valuable information for the application of CORA v2.0 data products. 展开更多
关键词 ocean reanalysis products sound velocity profile temporal and spatial distribution characteristics
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冷拉拔过程中含稀土铝镁合金的组织与力学性能演变 被引量:1
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作者 张欣 杨光恒 +3 位作者 王泽华 周泽华 易于 蔡新 《机械工程材料》 CAS CSCD 北大核心 2021年第10期34-42,共9页
熔炼制备不同稀土加入量的Al-3.0Mg-xRE(质量分数/%,x=0,0.12,0.31,RE为La+Ce)合金,研究了该合金的显微组织、硬度和拉伸性能在冷拉拔过程中的演变规律。结果表明:冷拉拔过程中,试验合金的晶粒拉长,第二相拉长并破碎成细小粒子,并在晶... 熔炼制备不同稀土加入量的Al-3.0Mg-xRE(质量分数/%,x=0,0.12,0.31,RE为La+Ce)合金,研究了该合金的显微组织、硬度和拉伸性能在冷拉拔过程中的演变规律。结果表明:冷拉拔过程中,试验合金的晶粒拉长,第二相拉长并破碎成细小粒子,并在晶界和枝晶界处逐渐聚集呈线状分布,Copper{112}〈111〉型变形织构强度逐渐增高;随着变形量的增大,合金的强度呈线性增大,塑性降低,显微硬度增大;适量稀土(0.12%)的加入能够改善合金组织与力学性能,但过量稀土(0.31%)的加入会导致合金中第二相数量和尺寸的增加,从而降低合金的力学性能。冷拉拔后,Al-3.0Mg-0.12RE合金中第二相的长度最小,数量最少,变形织构强度最高,力学性能最优。 展开更多
关键词 冷拉拔 铝镁合金 显微组织 力学性能
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