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Efficient conversion of aromatic and phenylpropanoid alcohols to acids by the cascade biocatalysis of alcohol and aldehyde dehydrogenases

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Synthetic and Systems Biotechnology 2024年第2期9卷 187-195页

作者： Zetian Qiu Xiaohui liu Jie Yu Yushuo Zhao guang-rong Zhao Shengying li Kun liu Lei Du li Ma State Key Laboratory of Microbial Technology Shandong UniversityQingdaoShandong266237China Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityYaguan Road 135Jinnan DistrictTianjin300350China School of Health Management Hengxing UniversityQingdaoShandong266100China

Benzyl and phenylpropanoid acids are widely used in organic synthesis of fine chemicals,such as pharmaceuticals and ***,biocatalysis of these acids has received less attention than chemical *** of the main challenges for biological production is the limited availability of alcohol dehydrogenases and aldehyde *** microorganisms are potential sources of these *** this study,129 alcohol dehydrogenases and 42 aldehyde dehydrogenases from Corynebacterium glutamicum,Pseudomonas aeruginosa,and Bacillus subtilis were identified and explored with various benzyl and phenylpropanoid alcohol and aldehyde substrates,among which four alcohol dehydrogenases and four aldehyde dehydrogenases with broad substrate specificity and high catalytic activity were ***,a cascade whole-cell catalytic system including ADH-90,ALDH-40,and the NAD(P)H oxidase LreNox was established,which showed high efficiency in converting cinnamyl alcohol and p-methylbenzyl alcohol into the respective carboxylic ***,this biocatalytic system can be easily scaled up to gram-level production,facilitating preparation purposes.

关键词： Benzyl acids Phenylpropanoid acids Alcohol dehydrogenases Aldehyde dehydrogenases Whole-cell catalysis

Regulations of m^(6)A and other RNA modifications and their roles in cancer

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Frontiers of Medicine 2024年第4期18卷 622-648页

作者： Xin-Hui Chen Kun-Xiong Guo Jing li Shu-Hui Xu Huifang Zhu guang-rong Yan Biomedicine Research Center Guangdong Provincial Key Laboratory of Major Obstetric DiseaseGuangdong Provincial Clinical Research Center for Obstetrics and GynecologyState Key Laboratory of Respiratory Diseasethe Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou510150China

RNA modification is an essential component of the epitranscriptome,regulating RNA metabolism and cellular *** types of RNA modifications have been identified to date;they include N^(6)-methyladenosine(m^(6)A),N^(1)-methyladenosine(m1A),5-methylcytosine(m5C),N^(7)-methylguanosine(m^(7)G),N^(6),2′-O-dimethyladenosine(m^(6)Am),N4-acetylcytidine(ac^(4)C),*** modifications,mediated by regulators including writers,erasers,and readers,are associated with carcinogenesis,tumor microenvironment,metabolic reprogramming,immunosuppression,immunotherapy,chemotherapy,etc.A novel perspective indicates that regulatory subunits and post-translational modifications(PTMs)are involved in the regulation of writer,eraser,and reader functions in mediating RNA modifications,tumorigenesis,and anticancer *** this review,we summarize the advances made in the knowledge of different RNA modifications(especially m^(6)A)and focus on RNA modification regulators with functions modulated by a series of factors in cancer,including regulatory subunits(proteins,noncoding RNA or peptides encoded by long noncoding RNA)and PTMs(acetylation,SUMOylation,lactylation,phosphorylation,etc.).We also delineate the relationship between RNA modification regulator functions and carcinogenesis or cancer ***,inhibitors that target RNA modification regulators for anticancer therapy and their synergistic effect combined with immunotherapy or chemotherapy are discussed.

关键词： RNA modification writers erasers readers regulatory subunits PTMs cancer

DLF-YOLOF:an improved YOLOF-based surface defect detection for steel plate

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Journal of Iron and Steel Research International 2024年第2期31卷 442-451页

作者： guang-hu liu Mao-xiang Chu rong-fen Gong Ze-hao Zheng School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051LiaoningChina

Surface defects can affect the quality of steel *** methods based on computer vision are currently applied to surface defect detection of steel ***,their real-time performance and object detection of small defect are still *** improved object detection network based on You Only Look One-level Feature(YOLOF)is proposed to show excellent performance in surface defect detection of steel plate,called ***,the anchor-free detector is used to reduce the network ***,deformable convolution network and local spatial attention module are introduced into the feature extraction network to increase the contextual information in the feature ***,the soft non-maximum suppression is used to improve detection accuracy ***,data augmentation is performed for small defect objects during training to improve detection *** show the average precision and average precision for small objects are 42.7%and 33.5%at a detection speed of 62 frames per second on a single GPU,*** shows that DLF-YOLOF has excellent performance to meet the needs of industrial real-time detection.

关键词： Steel surface defects detection YOLOF Anchor-free detector Small object detection Real-time detection

Interaction mechanism between BaZrO_(3)/Y_(2)O_(3) refractory and Ti_(2)Ni alloy melts

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Journal of Iron and Steel Research International 2024年第6期31卷 1376-1388页

作者： Xiao Hou guang-yao Chen Jian liu Ming-rui Lv Fei-hai Yu Qi-sheng Feng rong-bin li Xiong-gang Lu Chong-he li State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferromeallurgy and School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Shanghai Special Casting Engineering Technology Research Center Shanghai 201605China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314100ZhejiangChina School of Materials Science and Engineering Shanghai DianJi UniversityShanghai 201306China

The titanium alloys with highly chemical activity require stable crucible refractories that can withstand the erosion of alloy *** phase composition and microstructure are crucial factors that affect the stability of the refractory *** effect of Y_(2)O_(3) on the composition and microstructure of BaZrO_(3) crucible was systematically investigated,and the improved mechanism of the stability of BaZrO_(3)/Y_(2)O_(3) crucible was clarified in comparison with the BaZrO_(3) *** results showed that the erosion layer thickness of the BaZrO_(3)/Y_(2)O_(3) crucible was only 63μm,which was far less than that in the BaZrO_(3) crucible(485μm),and the erosion layer in the BaZrO_(3)/Y_(2)O_(3) crucible also exhibited a higher density than that in the BaZrO_(3) *** the sintering,Y_(2)O_(3) could improve the densification of the BaZrO_(3) crucible due to the solid solution effect between Y_(2)O_(3) and ZrO_(2),which also caused the evaporation of BaO,resulting in the generation of a Y_(2)O_(3)(ZrO_(2))film on the surface of the ***,the Y_(2)O_(3)(ZrO_(2))had higher thermodynamic stability than Y_(2)O_(3),confirming that the BaZrO_(3)/Y_(2)O_(3) crucible with high density exhibited a superior erosion resistance to titanium *** dual-phase structure provides a strategy to design a long-life and stable refractory for melting titanium alloys.

关键词： Barium zirconate Yttrium oxide Dual-phase refractory Titanium alloy Interaction

Kinematic calibration method with high measurement efficiency and robust identification for hybrid machine tools

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Chinese Journal of Aeronautics 2024年第3期37卷 468-482页

作者： liping WANG Mengyu li guang YU Weitao li Xiangyu KONG State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipment and Control Beijing 100084China

Geometric error is the main factor affecting the machining accuracy of hybrid machine *** calibration is an effective way to improve the geometric accuracy of hybrid machine *** necessity to measure both position and orientation at each pose,as well as the instability of identification in case of incomplete measurements,severely affects the application of traditional calibration *** this study,a kinematic calibration method with high measurement efficiency and robust identification is proposed to improve the kinematic accuracy of a five-axis hybrid machine ***,the configuration is introduced,and an error model is ***,by investigating the mechanism error characteristics,a measurement scheme that only requires tool centre point position error measurement and one alignment operation is ***,by analysing the effects of unmeasured degrees of freedom(DOFs)on other DOFs,an improved nonlinear least squares method based on virtual measurement values is proposed to achieve stable parameter identification in case of incomplete measurement,without introducing additional ***,the proposed calibration method is verified through simulations and *** proposed method can efficiently accomplish the kinematic calibration of the hybrid machine *** accuracy of the hybrid machine tool is significantly improved after calibration,satisfying actual aerospace machining requirements.

关键词： Hybrid machine tool Calibration Measurement scheme Improved nonlinear least squares method Virtual measurement values

Subarachnoid hemorrhage misdiagnosed as acute coronary syndrome leading to catastrophic neurologic injury: A case report

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World Journal of Clinical Cases 2024年第1期12卷 148-156页

作者： Jun-Ming lin Xiao-Jun Yuan guang li Xin-rong Gan Wen-Hua Xu Department of Orthopaedic Surgery People's Hospital of Yichun CityYichun 336000Jiangxi ProvinceChina

BACKGROUND Elevated levels of cardiac troponin and abnormal electrocardiogram changes are the primary basis for clinical diagnosis of acute coronary syndrome(ACS).Troponin levels in ACS patients can often be more than 50 times the upper reference *** patients with subarachnoid hemorrhage(SAH)also show electrocardiogram abnormalities,myocardial damage,and elevated cardiac *** ACS patients,patients with SAH only have a slight increase in troponin,and the use of anticoagulants or antiplatelet drugs is *** of the opposite treatment modalities,it is essential for clinicians to distinguish between SAH and *** SUMMARY A 56-year-old female patient was admitted to the emergency department at night with a sudden onset of severe back *** final diagnosis was intraspinal hematoma in the thoracic *** performed an emergency thoracic spinal canal hematoma evacuation procedure with the assistance of a ***,diffuse hematoma formation was found in the T7-T10 spinal canal,and no obvious spinal vascular malformation changes were *** head and spinal magnetic resonance imaging(MRI)showed a small amount of SAH in the skull,no obvious abnormalities in the cervical and thoracic spinal canals,and no abnormal signals in the lumbar spinal ***-dominal aorta computed tomography angiography showed no vascular *** motor system examination showed Medical Research Council Scale grade 1/5 strength in both lower extremities,and the patient experienced decreased sensation below the T12 rib margin and reported a Visual Analog Scale score of *** Extremely elevated troponin levels(more than 50 times the normal range)are not unique to coronary artery *** can also result in extremely high troponin levels,and antiplatelet drugs are contraindicated in such *** MRI can help in the early differential diagnosis,as a misdiagnosis of ACS can lead to catastroph

关键词： Acute coronary syndrome Spontaneous spinal subdural hematoma Misdiagnosis Catastrophic neurological injury Case report

Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances

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China Ocean Engineering 2024年第2期38卷 271-284页

作者： ZHOU li WANG Guo-rong WAN Min School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China Energy Equipment Institute Southwest Petroleum UniversityChengdu 610500China National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental *** control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control ***,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each *** direction interference observers are designed to track the timevarying boundary *** this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead *** addition,the stability of the closed-loop system is proven by Lyapunov stability *** the system states are bounded,and the vibration offset of the riser converges to a small area of the initial ***,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.

关键词： adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control

A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： Ji-guang li Xin Guo Huan-Di Hou Heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation *** total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction *** asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

Variable Selection for Generalized linear Model with Highly Correlated Covariates

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1458-1480页

作者： li li YUE Wei Tao WANG Gao rong li School of Statistics and Data Science Nanjing Audit UniversityNanjing 211815P.R.China School of Mathematics Statistics and MechanicsBeijing University of TechnologyBeijing 100124P.R.China School of Statistics Beijing Normal UniversityBeijing 100875P.R.China

The penalized variable selection methods are often used to select the relevant covariates and estimate the unknown regression coefficients simultaneously,but these existing methods may fail to be consistent for the setting with highly correlated *** this paper,the semi-standard partial covariance(SPAC)method with Lasso penalty is proposed to study the generalized linear model with highly correlated covariates,and the consistencies of the estimation and variable selection are shown in high-dimensional settings under some regularity *** simulation studies and an analysis of colon tumor dataset are carried out to show that the proposed method performs better in addressing highly correlated problem than the traditional penalized variable selection methods.

关键词： Generalized linear model highly correlated covariates Lasso penalty semi-standard partial covariance variable selection