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The release and catabolism of ferulic acid in plant cell wall by rumen microbes:A review

Animal Nutrition 2022年第2期9卷 335-344页

作者： Yan-Lu Wang Wei-Kang Wang qi-chao wu Hong-Jian Yang State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Ferulic acid(FA)is one of the most abundant hydroxycinnamic acids in the plant world,especially in the cell wall of grain bran,in comparison with forage and crop residues.Previous studies noted that FA was mainly linked with arabinoxylans and lignin in plant cell walls in ester and ether covalent forms.After forages were ingested by ruminant animals or encountered rumen microbial fermentation in vitro,these cross-linkages form physical and chemical barriers to protect cell-wall carbohydrates from microbial attack and enzymatic hydrolysis.Additionally,increasing studies noted that FA presented some toxic effect on microbial growth in the rumen.In recent decades,many studies have addressed the relationships of ester and/or ether-linked FA with rumen nutrient digestibility,and there is still some controversy whether these linkages could be used as a predicator of forage digestibility in ruminants.The authors in this review summarized the possible relationships between ester and/or ether-linked FA and fiber digestion in ruminants.Rumen microbes,especially bacteria and fungi,were found capable of breaking down the ester linkages within plant cell walls by secreting feruloyl and p-coumaroyl esterase,resulting in the release of free FA and improvement of cell wall digestibility.The increasing evidence noted that these esterases secreted by rumen microbes presented synergistic effects with xylanase and cellulase to effectively hydrolyze forage cell walls.Some released FA were absorbed through the rumen wall directly and entered into blood circulation and presented antioxidant effects on host animals.The others were partially catabolized into volatile fatty acids by rumen microbes,and the possible catabolic pathways discussed.To better understand plant cell wall degradation in the rumen,the metabolic fate of FA along with lignin decomposition mechanisms are needed to be explored via future microbial isolation and incubation studies with aims to maximize dietary fiber intake and enhance fiber digestion in ruminant animals.

关键词： Rumen microbes Ferulic acid Fiber digestion

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Wheat silage partially replacing oaten hay exhibited greater feed efficiency and fibre digestion despite low feed intake by feedlot lambs

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Animal Nutrition 2023年第4期15卷 332-340页

作者： Zhao-Yang Cui Wen-Juan Li Wei-Kang Wang qi-chao wu Yao-Wen Jiang Ailiyasi Aisikaer Fan Zhang He-Wei Chen Hong-Jian Yang State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

This study aimed to investigate the feeding effect of wheat silage on growth performance,nutrient digestibility,rumen fermentation,and microbiota composition in feedlot lambs.Sixty-four male crossbred Chinese Han lambs(BW=27.8±0.67 kg,3 months of age)were randomly assigned to four ration groups with wheat silage replacing 0%(WS0),36%(WS36),64%(WS64),and 100%(WS100)of oaten hay on forage dry matter basis.The concentrate-to-forage ratio was 80:20 and the feeding trial lasted 52 d.Increasing wheat silage inclusion linearly decreased dry matter intake by 4%to 27%(P<0.01).However,increasing the wheat silage replacement of oaten hay by no more than 64%improved the feed efficiency by 14%as noted by the feed-to-gain ratio(P=0.04).Apparent digestibility of organic matter(P<0.01),neutral detergent fibre(P=0.04)and acid detergent fibre(P<0.01)quadratically increased.Ammonia nitrogen(P=0.01)decreased while microbial protein production(P<0.01)increased with the increase of wheat silage inclusion.Total volatile fatty acids concentration increased quadratically with the increase of wheat silage inclusion(P<0.01),and the highest occurred in WS64.The molar proportion of acetate(P<0.01)and acetate-to-propionate ratio(P=0.04)decreased while butyrate(P<0.01)and isovalerate(P=0.04)increased.Increasing wheat silage inclusion increased the Firmicutes-toBacteroidota ratio by 226%to 357%,resulting in Firmicutes instead of Bacteroidota being the most abundant phylum.The relative abundance of cellulolytic Ruminococcus numerically increased but that of amylolytic Prevotella(P<0.01)decreased as increasing wheat silage inclusion.Taken together,increasing wheat silage replacement of oaten hay by no more than 64%exhibited greater feed efficiency and fibre digestion despite low feed intake by feedlot lambs due to the change of Firmicutes-to-Bacteroidota ratio in the rumen.

关键词： Wheat silage Oaten hay Growth performance Nutrient digestibility Rumen fermentation Feedlot lamb

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In-situ Enhanced Toughening of Poly（ethylene terephthalate）/elastomer Blends via Gamma-Ray Radiation at Presence of Trimethylolpropane Triacrylate

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Chinese Journal of Chemical Physics 2016年第6期29卷 703-709,I0001,I0002页

作者： Li-zhao Xie Le-chen Chen Mo-zhen Wang qi-chao wu Xiao Zhou Xue-wu Ge CASKeyLaboratoryofSoftMatterChemistry DepartmentofPolymerScienceandEngineeringUniversityofScienceandTechnologyofChinaHefei230026China GuangdongTiananNewMaterialCo. Ltd.Foshan528000China

Gamma 光线放射总是是在聚合物混合修改界面的性质的一个方便、有效的方法。在这个工作， trimethylolpropane triacrylate (TMPTA ) 的小数量被合并到(乙烯 terephthalate )( 宠物) poly， /random terpolymer 弹性体(ST2000 ) 由融化... 详细信息

Gamma 光线放射总是是在聚合物混合修改界面的性质的一个方便、有效的方法。在这个工作， trimethylolpropane triacrylate (TMPTA ) 的小数量被合并到(乙烯 terephthalate )( 宠物) poly， /random terpolymer 弹性体(ST2000 ) 由融化混合相配。TMPTA 的存在将在相配的高温度导致宠物和 ST2000 分子的链的 crosslinking，导致在影响力量的改进但是在张力的力量的损失。当 PET/ST2000 混合被 gamma 光线放射照耀时，综合机械性质能在高吸收的剂量显著地被提高。在 100 kGy 的剂量的照耀的样品甚至 couldnt 在影响测试负担下面被打破，并且同时，将近不有张力的力量的损失。基于混合的断裂影响的表面形态学的分析，在高吸收的剂量的 gamma 光线放射能在 situ 推进，这能被结束由支持 TMPTA 和聚合物链的 crosslinking 反应提高界面的粘附。作为结果， PET/ST2000 混合的坚韧和力量能戏剧性地被改进。这个工作向一个面部、实际的方法提供到聚合物混合的制造高坚韧和力量。

关键词：三羟甲基丙烷三丙烯酸酯对苯二甲酸乙二醇酯聚合物共混物共聚物弹性体 γ射线辐射增强增韧 TMPTA 原位

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Synthesis and morphology control of raspberry-like poly(ethylene terephthalate)/polyacrylonitrile microspheres

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Chinese Chemical Letters 2016年第2期27卷 195-199页

作者： Yong-Fei Xu Mo-Zhen Wang qi-chao wu Xiao Zhou Xue-wu Ge CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China School of Materials and Chemical Engineering Anhui Jianzhu University Guangdong Tianan New Material Co. Ltd.

The fabrication of raspberry-like poly（ethylene terephthalate）/polyacrylonitrile（PET/PAN） microspheres by g-ray radiation-induced polymerization of acrylonitrile on micron-sized PET microspheres were first reported in this work. A PET emulsion was firstly prepared by dispersing a PET solution with 1,1,2,2-tetrachloroethane/phenol mixture as the solvent into an aqueous solution of sodium dodecyl sulfate.Then, PET microspheres were formed by precipitating the PET emulsion droplets from ethanol. The influence of the PET solvent and the weight ratio of ethanol to PET emulsion on the morphology of the PET microspheres had been investigated. After the surface of the prepared PET microspheres was grafted with poly（acrylic acid）, the grafting polymerization of AN also had been successfully initiated by g-ray radiation to form PAN microspheres with a size of about 100 nm on the PET microspheres. This work provides a new method to fabricate micron-sized PET microspheres, and further expands the functionalization of PET and its application fields.

关键词： PET emulsion Emulsion precipitation PET microsphere Raspberry-like microsphere PET/PAN composite microspheres

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Melatonin for the treatment of spinal cord injury

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Neural Regeneration Research 2018年第10期13卷 1685-1692页

作者： Yan Zhang Wen-Xiu Zhang Yan-Jun Zhang Ya-Dong Liu Zong-Jian Liu qi-chao wu Yun Guan Xue-Ming Chen Central Laboratory Beijing Luhe HospitalCapital Medical University Department of Orthopedics Beijing Luhe HospitalCapital Medical University Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Department of Neurological Surgery Johns Hopkins University

Spinal cord injury（SCI） from trauma or disease severely impairs sensory and motor function. Neurorehabilitation after SCI is a complex medical process that focuses on improving neurologic function and repairing damaged connections in the central nervous system. An increasing number of preclinical studies suggest that melatonin may be useful for the treatment of SCI. Melatonin is an indolamine that is primarily secreted by the pineal gland and known to be regulated by photoperiodicity. However, it is also a versatile hormone with antioxidative, antiapoptotic, neuroprotective, and anti-inflammatory properties. Here, we review the neuroprotective properties of melatonin and the potential mechanisms by which it might be beneficial in the treatment of SCI. We also describe therapies that combine melatonin with exercise, oxytetracycline, and dexamethasone to attenuate the secondary injury after SCI and limit potential side effects. Finally, we discuss how injury at different spinal levels may differentially affect the secretion of melatonin.

关键词： spinal cord injury melatonin secondary damage neuroprotection antioxidative antiapoptotic anti-inflammatory synergistic effects neural regeneration

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Current status and future development of aortic stent fenestration-assisted techniques

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Chinese Medical Journal 2024年第6期137卷 752-754页

作者： Gezheng Chen Xiaoyu qi Wanying wu Dongsheng Fu Li qin chao Yang Department of Vascular Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China Department of Vascular Surgery Nanjing Drum Tower HospitalAffiliate Hospital of Nanjing University Medical SchoolNanjingJiangsu 210008China

To the Editor:In 1996,Parodi et al^([1])introduced the technique of fenestrated endovascular aneurysm repair(f-EVAR)for treatment of pararenal abdominal aortic aneurysms.They use physician modified stent grafts(PMSGs)for fenestration,which allows for stent grafts to gain sufficient proximal sealing zones and maintain the blood perfusion of visceral arteries.^([2])Stent grafts used in the f-EVAR technique developed from PMSGs to Company Modified Devices(CMDs)and off-the-shelf devices.^([3])To improve the precision of PMSGs and shorten the time of stent graft modification,various techniques that assist in the process of fenestration have been researched and developed,including 3-dimensional(3D)printing technique,the Mixed Reality(MR)technique,and the 3D parametric surface planar topological guide plate.This article describes the current status and future development of these techniques.

关键词： aortic perfusion arteries

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Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research(International) 2024年第1期31卷 252-263页

作者： Guo-ning He Shi-qi Wan Bo Jiang chao-lei Zhang Ya-zheng Liu Chun-jing wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were investigated.Hot compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate observations.Hot compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was better.The tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,respectively.The addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the deformability.In addition,the interaction between inclusions and microalloyed elements was also significant.NbC particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

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Active flutter suppression of nonlinear fin-actuator system via inverse system and immersion and invariance method

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Chinese Journal of Aeronautics 2024年第4期37卷 343-362页

作者： Jin LU Zhigang wu chao YANG Chinese Aeronautical Establishment Beijing 100029China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Structural nonlinearities such as freeplay will affect the stability and even flight safety of the fin-actuator system.There is a lack of a practical method for designing Active Flutter Suppression (AFS) control laws for nonlinear fin-actuator systems.A design method for the AFS controller of the nonlinear all-movable fin-electromechanical actuator system is established by combining the inverse system and the Immersion and Invariance (I&I) theory.First,the composite control law combining the inverse system principle and internal model control is used to offset the nonlinearity and dynamics of the actuator,so that its driving torque can follow the ideal signal.Then,the ideal torque of the actuator is designed employing the I&I theory.The unfavorable oscillation of the fin is suppressed by making the output torque of the actuator track the ideal signal.The simulation results reveal that the proposed AFS method can increase the flutter speed of the nonlinear finactuator system with freeplay,and a set of controller parameters is also applicable for wider freeplay within a certain range.The power required for the actuator does not exceed the power that can be provided by the commonly used aviation actuator.This method can also resist a certain level of noise and external disturbance.

关键词： Aeroelasticity Active flutter suppression Fin-actuator system Freeplay Inverse system Immersion and invariance

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Intelligent feedforward gust alleviation based on neural network

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Chinese Journal of Aeronautics 2024年第3期37卷 116-132页

作者： Yitao ZHOU Zhigang wu chao YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

This paper proposes a neural network-based intelligent feedforward gust alleviation framework,which includes a neural network identification model and a neural network controller.A neural network training dataset is formed by collecting flight data and the gust data encountered during the aircraft flight.A neural network identification model is first trained to accurately predict the aircraft’s output.Then,based on the output of the identification model and the collected flight data,the parameters of the time-delay neural network controller are obtained through a learning process.The simulation results show that the designed intelligent controller has good gust alleviation effects for both continuous turbulence excitation and discrete gust excitation.For example,when the aircraft is 40000 kg and the flight speed is 0.81Ma,the controller achieves a 67.82%reduction in wingtip acceleration and a 35.90%reduction in center of mass acceleration under continuous turbulence excitation.When considering the measurement uncertainties,such as noise existing in the collected data,the trained controller can still achieve an acceptable gust alleviation effect.Finally,considering a flight in which the aircraft mass is constantly changing,the intelligent controller,which continuously learns from new flight data,maintains a good gust alleviation effect throughout the flight.

关键词： Gust alleviation Intelligent control Feedforward control Neural networks Time-varying aircraft

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A review on the transformation of birnessite in the environment:Implication for the stabilization of heavy metals

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Journal of Environmental Sciences 2024年第5期139卷 496-515页

作者： Miao Shi qingzhu Li qingwei Wang Xuelei Yan Bensheng Li Linhai Feng chao wu Rongrong qiu Hongkai Zhang Zhihui Yang Weichun Yang qi Liao Liyuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment ofHeavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410083China

Birnessite is ubiquitous in the natural environment where heavy metals are retained and easily transformed.The surface properties and structure of birnessite change with the changes in external environmental conditions,which also affects the fate of heavy metals.Clarifying the effect and mechanism of the birnessite phase transition process on heavy metals is the key to taking effective measures to prevent and control heavy metal pollution.Therefore,the four transformation pathways of birnessite are summarized first in this review.Second,the relationship between transformation pathways and environmental conditions is proposed.These relevant environmental conditions include abiotic(e.g.,co-existing ions,pH,oxygen pressure,temperature,electric field,light,aging,pressure)and biotic factors(e.g.,microorganisms,biomolecules).The phase transformation is achieved by the key intermediate of Mn(Ⅲ)through interlayer-condensation,folding,neutralizationdisproportionation,and dissolution-recrystallization mechanisms.The AOS(average oxidation state)of Mn and interlayer spacing are closely correlated with the phase transformation of birnessite.Last but not least,the mechanisms of heavy metals immobilization in the transformation process of birnessite are summed up.They involve isomorphous substitution,redox,complexation,hydration/dehydration,etc.The transformation of birnessite and its implication on heavy metals will be helpful for understanding and predicting the behavior of heavy metals and the crucial phase of manganese oxides/hydroxides in natural and engineered environments.

关键词： Birnessite Transformation Heavy metals Pathways Mechanism

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