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Phase separation,transcriptional elongation control,and human diseases

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Journal of Molecular Cell Biology 2021年第4期13卷 314-318页

作者： Chenghao Guo Zhuojuan luo Chengqi lin School of Life Science and Technology Key Laboratory of Developmental Genes and Human DiseaseSoutheast UniversityNanjing 210096China Co-innovation Center of Neuroregeneration Nantong UniversityNantong 226019China

Precise regulation of gene transcription is of great importance to development and ***-proximal transcriptional pause is a key and general mechanism to precisely control transcription in *** to transcription initiation and synthesis of a short RNA,RNA polymerase Ⅱ(Pol Ⅱ)usually pauses at the promoter-proximal regions,standing by for further signals to be released into the productive elongation *** regulation of Pol Ⅱ pausing and release is achieved by the concerted action of many negative and positive elongation factors,including the super elongation complex(SEC).Recent studies suggested that phase-separated assemblies of transcription regulatory complexes could provide a general biophysical basis for the dynamic regulation of transcription in response to various cellular needs,though direct evidence at endogenous level in living cells is still largely ***,we summarize and discuss latest advances in understanding how phase separation contributes to RNA polymerase ll-mediated transcription,with a focus on transcriptional pause and release.

关键词： separation release elongation

Optimization of CZTSSe thin film solar cell performance using PbS back surface field layer

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Optoelectronics Letters 2025年

作者： WENJING luo ZHIJIAN BAI YUMING XUE luoXIN WANG YANHONG DING HONGLI DAI Tianjin Key Laboratory of Film Electronic & Communication devices， School of Electronics Information Engineering， Tianjin University of Technology School of Materials Science and Engineering ，Jilin University

CZTSSe is an Earth-abundant， environmentally friendly， and low-cost material， with a current record power conversion efficiency of 14.9%， This result is well below the prediction of the Shockley-Queisser limit. To improve the performance of solar cells， a layer of PbS (BSF) was added to the CZTSSe， which was simulated using the SCAPS-1D software. The optimal photovoltaic performance of AZO/ZnO/CdS/CZTSSe/PbS/Mo was studied by changing the parameters of the CZTSSe absorption layer and PbS layer. Studies have shown that the efficiency can be increased to 20.86% after using PbS.

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Influence of Alignment Errors on Contact Pressure during Straight Bevel Gear Meshing Process

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1089-1099页

作者： HAN Xinghui HUA lin deNG Song luo Qiuping Hubei Key Laboratory of Advanced Technology for Automotive Components School of Automotive EngineeringWuhan University of Technology

Straight bevel gears are widely applied in automotive, aerospace, chemical and many other fields as one of the most common type of gears. Currently, the researches on straight bevel gears have focused on the fields of fatigue, wear, noise and vibration, while little attention is paid to the effect of multiple alignment errors on the gear tooth wear. To study the influence of alignment errors on the gear tooth wear, a simulated model of a straight bevel gear pair is established. Then, the contact pressure on the tooth surface is analyzed under the various alignment errors according to the Archard wear relationship. The main combinations of alignment errors played vital roles on the tooth wear are investigated. The result shows that under the single alignment error, the contact pressure moves to the tooth heel and increases greatly at here when ？P=0.1 or ？G=0.1; when ？E=–0.03, the contact pressure greatly increases at the tooth heel, but it obviously increases at the tooth toe when ？E=0.03; the alignment error ？γ=1 has little effect on the contact pressure on the tooth surface. Moreover, the combination of ？P, ？G, ？E〈0 and ？γ is the most dangerous type among the multiple alignment errors. This research provides valuable guidelines for predicting the tooth wear under various alignment errors.

关键词： straight bevel gear multiple alignment errors contact pressure wear

A general pressure drop model based on liquid holdup of gas-liquid flow in micro-packed beds

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CHINESE JOURNAL OF CHEMICAL ENGINEERING 2024年第12期76卷 147-156页

作者： Wang, Junjie Sheng, lin deng, Jiang luo, Guangsheng Tsinghua Univ Dept Chem Engn State Key Lab Chem Engn Beijing 100084 Peoples R China

The understanding of the gas-liquid flow characteristics in a micro-packed bed reactor is still immature, especially for many gas-organic working systems commonly used in industry. Accordingly, this study proposes a platform to investigate the gas-liquid flow characteristics in a micro-packed bed reactor and presents a unified expression for these characteristics of both organic and aqueous liquid phase. The influence of two-phase flow rate, working solution viscosity, and packing particle size on the liquid holdup and pressure drop were studied. The gas-organic working systems results show that the liquid holdup ranges between 0.5 and 0.8 and pressure drop ranges from 50 to 350 kPa center dot m-1. In particular, a strong correlation between the two flow characteristics parameters (liquid holdup and pressure drop) was proposed for the first time. Finally, a general pressure drop mathematical prediction model in micropacked bed were developed. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Gas-liquid flow Micro-packed bed reactors Liquid holdup Pressure drop Mathematical model

Local Structures and Chemical Properties of deprotonated Arginine

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Chinese Journal of Chemical Physics 2012年第6期25卷 681-686,I0003,I0004页

作者： Hong-bao Li Zi-jing lin Yi luo Hefei National Laboratory for Physical Sciences at the Microscale and department of Physics University of Science and Technolo&y of China Hefei 230025 China department of Theoretical Chemistry and Biology School of BiotechnoloEy Royal Institute ofTechnoloEy S-106 91 Stockholm Sweden

The potential energy surface of gaseous deprotonated arginine has been systematically in- vestigated by first principles calculations. At the B3LYP/6-31G（d） level, apart from the identification of several stable local structures, a new global minimum is located which is about 6.56 k J/tool more stable than what has been reported. The deprotonated arginine molecule has two distinct forms with the deprotonation at the carboxylate group （COO-）. These two forms are bridged by a very high energy barrier and possess very different IR spectral profiles. Our calculated proton dissociation energy and gas-phase acidity of argi- nine molecule are found to be in good agreement with the corresponding experimental results. The predicted geometries, dipole moments, rotational constants, vertical ionization energies and IR spectra of low energy conformers will be useful for future experimental measurements.

关键词： deprotonated arginine Energy barrier IR spectrum Gas-phase acidity

A novel optimal design for an application-oriented synthetic jet actuator

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Chinese Journal of Aeronautics 2014年第3期27卷 514-520页

作者： deng Xiong Xia Zhixun luo Zhenbing Wang lin Science and Technology on Scramjet Laboratory National University of Defense Technology

The evaluation indicator for the performance of a synthetic jet actuator （SJA） is well-defined because of its various applications, which require optimal design to improve its performance and extend its field of application. This paper presents a novel approach to the optimal design of an SJA applied to enhance fuel/air mixture. It optimizes the combination of an actuator＇s geometric parameters by selecting the strength of vortex pairs as the evaluation indicator, coupled with orthogonal experiments and analysis of variance （AOV）. The results indicate that slot width is the most notable factor influencing the strength of vortex pairs, followed by cavity height and slot depth. The optimal value of the strength of vortex pairs increases by 32.5%over the experimental data of the base case, and more than 8.4%compared with the simulation results of the orthogonal experiments. It is concluded that the optimal method can effectively improve the performance of an SJA applied in mixing enhancement, reducing the test numbers and the associated design cycle and cost.

关键词： Analysis of variance Evaluation indicator Orthogonal experiment Strength of vortex pairs Synthetic jet

Spatiotemporal variations of PM_(2.5) and PM_(10) concentrations between31 Chinese cities and their relationships with SO_2,NO_2,CO and O_3

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Particuology 2015年第3期13卷 141-149页

作者： Yangyang Xie Bin Zhao lin Zhang Rong luo department of Building Science School of ArchitectureTsinghua University department of Electronic Engineering Tsinghua University

The variations of mass concentrations of PM2.5, PMl0, SO2, NO2, CO, and 03 in 31 Chinese provincial capital cities were analyzed based on data from 286 monitoring sites obtained between March 22, 2013 and March 31,2014. By comparing the pollutant concentrations over this length of time, the characteristics of the monthly variations of mass concentrations of air pollutants were determined. We used the Pearson correlation coefficient to establish the relationship between PM2.5, PM10, and the gas pollutants. The results revealed significant differences in the concentration levels of air pollutants and in the variations between the different cities. The Pearson correlation coefficients between PMs and NO2 and SO2 were either high or moderate （PM2.s with NO2： r = 0.256-0.688, mean r = 0,498：PM10 with NO2： r = 0.169-0.713, mean r=0.493; PM2.5 with SO2： r=0.232-0.693, mean r=0.449; PM10 with SO2： r=0.131-0.669, mean r = 0.403）. The correlation between PMs and CO was diverse （PM2.5： r = 0.156-0.721, mean r = 0.437; PMl0： r= 0.06-0.67, mean r= 0.380）. The correlation between PMs and 03 was either weak or uncorrelated （PM2.s： r= -0,35 to 0.089, mean r= -0.164; PM10： r= -0.279 to 0.078, mean r= -0.127）, except in Haikou （PM2.5： r=0.500; PM10： r=0,509）.

关键词： PM2.5PM40 Atmospheric air pollutantIndoor environmentOutdoor environment

Leucosceptroid B from glandular trichomes of Leucosceptrum canum reduces fat accumulation in Caenorhabditis elegans through suppressing unsaturated fatty acid biosynthesis

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Chinese Journal of Natural Medicines 2019年第12期17卷 892-899页

作者： linG Yi TENG lin-lin HUA Juan LI de-Sen luo Shi-Hong LIU Yan-Chun LIU Yan LI Sheng-Hong State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

Obesity that is highly associated with numerous metabolic diseases has become a global health issue *** sesterterpenoids are an important group of natural products with great potential;thus,their bioactivities deserve extensive ***-seq analysis indicated that leucosceptroid B,a sesterterpenoid previously discovered from the glandular trichomes of Leucosceptrum canum,significantly regulated the expression of 10 genes involved in lipid metabolism in Caenorhabditis ***,leucosceptroid B was found to reduce fat storage,and downregulate the expression of two stearoyl-CoA desaturase(SCD)genes fat-6 and fat-7,and a fatty acid elongase gene elo-2 in wild-type *** addition,leucosceptroid B significantly decreased fat accumulation in both fat-6 and fat-7 mutant worms but did not affect the fat storage of fat-6;fat-7 double *** findings indicated that leucosceptroid B reduced fat storage depending on the downregulated expression of fat-6,fat-7 and elo-2 and thereby inhibiting the biosynthesis of the corresponding unsaturated fatty *** findings provide new insights into the development and utilization of plant sesterterpenoids as potential antilipemic agents.

关键词： Sesterterpenoid Leucosceptroid B Leucosceptrum canum Caenorhabditis elegans Fat accumulation Fatty acid biosynthesis Antilipemic agent

Pulmonary Langerhans cell histiocytosis and multiple system involvement:A case report

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World Journal of Clinical Cases 2021年第35期9卷 11029-11035页

作者： lin luo Yan-Xia Li department of Critical Care Medicine The Second Hospital of Dalian Medical UniversityDalian 116023Liaoning ProvinceChina department of Respiratory and Critical Care Medicine Institute of Respiratory DiseasesThe First Affiliated Hospital of Dalian Medical UniversityDalian 116011Liaoning ProvinceChina

BACKGROUND Pulmonary Langerhans cell histiocytosis(PLCH)is a relatively rare type of lung disease,common in middle-aged smoking *** is characterized by proliferation and infiltration of Langerhans cells,and the formation of multiple parabronchial mesenchymal nodules in lung tissue,and may lead to organ *** are no typical symptoms and signs,and it is easily misdiagnosed or missed,and therefore deserves clinical attention and further *** SUMMARY We describe the case of a nonsmoking 46-year-old man with PLCH diagnosed based on clinical manifestations of fever and dry cough,with a history of hypothyroidism and diabetes insipidus for 9 *** tomography(CT)-and CT-guided puncture examinations revealed no abnormalities,and he ultimately underwent thoracoscopic biopsy to confirm the *** pathological diagnosis was *** function was maintained by *** magnetic resonance imaging showed that the pituitary stalk had become *** LCH often involves multiple ***,the pathogenesis is not clear,clinical manifestations lack specificity,and diagnosis requires special *** of PLCH can significantly benefit from comprehensive multidisciplinary analysis.

关键词： Pulmonary Langerhans cell histiocytosis Multiple systems Hypothyroidism Diabetes insipidus Case report