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Patterns,magnitude,and controlling factors of hydraulic redistribution of soil water by Tamarix ramosissima roots

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Journal of Arid Land 2013年第3期5卷 396-407页

作者： TengFei YU qi FENG JianHua SI HaiYang XI Wei LI Research School of Arid Environment and Climate Change Lanzhou University Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Gansu Hydrology and Water Resources Engineering Research Center

Tamarix spp. （Saltcedar） is a facultative phreatophyte that can tolerate drought when groundwater is not accessed. In addition to deep water uptake, hydraulic redistribution （HR） is another factor contributing to the drought tolerance of Tarnarix spp. In this study, data on soil volumetric moisture content （0）, lateral root sap flow, and relevant climate variables were used to investigate the patterns, magnitude, and controlling factors of HR of soil water by roots of Tamarix ramosissima Ledeb. in an extremely arid land in Northwest China. Results showed evident diurnal fluctuations in 0 at the depths of 30 and 50 cm, indicating ＂hydraulic lift＂（HL）. 0 increased remarkably at 10 and 140 cm but decreased at 30 and 50 cm and slightly changed at 80 cm after rainfall, suggesting a possible ＂hydraulic descent＂（HD）. However, no direct evidence was observed in the negative flow of lateral roots, supporting HR （including HL and HD） of T. ramosissima. The HR pathway unlikely occurred via lateral roots; instead, HR possibly occurred through adventitious roots with a diameter of 2-5 mm and a length of 60-100 cm. HR at depths of 20-60 cm ranged from 0.01-1.77 mm/d with an average of 0.43 mm/d, which accounted for an average of 22% of the estimated seasonal total water depletion at 0-160 cm during the growing season. The climate factors, particularly vapor pressure deficit and soil water potential gradient, accounted for at least 33% and 45% of HR variations with depths and years, respectively. In summary, T. ramosissima can be added to the wide list of existing species involved in HR. High levels of HR may represent a considerable fraction of daily soil water depletion and substantially improve plant water status. HR could vary tremendously in terms of years and depths, and this variation could be attributed to climate factors and soil water potential gradient.

关键词： drought tolerance phreatophyte hydraulic redistribution root sap flow Tamarix ramosissima

Lineage-specific evolution of bitter taste receptor genes in the giant and red pandas implies dietary adaptation

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Integrative Zoology 2018年第2期13卷 152-159页

作者： Lei SHAN qi WU Le WANG Lei ZHANG Fuwen WEI Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijingChina University of Chinese Academy of Science BeijingChina Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingChina

Taste 2 receptors(TAS2R)mediate bitterness perception in mammals,thus are called bitter taste *** is believed that these genes evolved in response to species-specific *** giant panda(ailuropoda melanoleuca)and red panda(ailurus fulgens styani)in the order Carnivora are specialized herbivores with an almost exclusive bamboo diet(>90%bamboo).Because bamboo is full of bitter tasting compounds,we hypothesized that adaptive evolution has occurred at TAS2R genes in giant and red pandas throughout the course of their dietary ***,we characterized 195 TAS2R genes in 9 Carnivora species and examined selective pressures on these *** found that both pandas harbor more putative functional TAS2R genes than other carnivores,and pseudogenized TAS2R genes in the giant panda are different from the red *** purifying selection on TAS2R1,TAS2R9 and TAS2R38 in the giant panda,and TAS2R62 in the red panda,has been strengthened throughout the course of adaptation to bamboo diet,while selective constraint on TAS2R4 and TAS2R38 in the red panda is ***,a few positively selected sites on TAS2R42 have been specifically detected in the giant *** results suggest an adaptive response in both pandas to a dietary shift from carnivory to herbivory,and TAS2R genes evolved independently in the 2 *** findings provide new insight into the molecular basis of mammalian sensory evolution and the process of adaptation to new ecological niches.

关键词： bitter taste receptor gene dietary adaptation giant panda red panda

African Bison Optimization Algorithm:A New Bio-Inspired Optimizer with Engineering Applications

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Computers, Materials & Continua 2024年第10期81卷 603-623页

作者： Jian Zhao Kang Wang Jiacun Wang Xiwang Guo Liang qi School of Science University of Science and Technology LiaoningAnshan114051China Team of Artificial Intelligence Theory and Application University of Science and Technology LiaoningAnshan114051China Department of Computer Science and Software Engineering Monmouth UniversityWest Long BranchNJ 07764USA Information and Control Engineering College Liaoning Petrochemical UniversityFushun113000China Department of Computer Science and Technology Shandong University of Science and TechnologyQingdao266590China

This paper introduces the African Bison Optimization(ABO)algorithm,which is based on biological *** is inspired by the survival behaviors of the African bison,including foraging,bathing,jousting,mating,and *** foraging behavior prompts the bison to seek a richer food source for *** bison find a food source,they stick around for a while by bathing *** jousting behavior makes bison stand out in the population,then the winner gets the chance to produce offspring in the mating *** eliminating behavior causes the old or injured bison to be weeded out from the herd,thus maintaining the excellent *** above behaviors are translated into ABO by mathematical *** assess the reliability and performance of ABO,it is evaluated on a diverse set of 23 benchmark functions and applied to solve five practical engineering problems with *** findings from the simulation demonstrate that ABO exhibits superior and more competitive performance by effectively managing the trade-off between exploration and exploitation when compared with the other nine popular metaheuristics algorithms.

关键词： Optimization metaheuristics African bison optimization engineering problems

Role of epigenetics in transformation of inflammation into colorectal cancer

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World Journal of Gastroenterology 2019年第23期25卷 2863-2877页

作者： Zhen-Hua Yang Yan-qi Dang Guang Ji Institute of Digestive Diseases Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China Digestive Endoscopy Department Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China

Molecular mechanisms associated with inflammation-promoted tumorigenesis have become an important topic in cancer research. Various abnormal epigenetic changes, including DNA methylation, histone modification, chromatin remodeling, and noncoding RNA regulation, occur during the transformation of chronic inflammation into colorectal cancer(CRC). These changes not only accelerate transformation but also lead to cancer progression and metastasis by activating carcinogenic signaling pathways. The NF-κB and STAT3 signaling pathways play a particularly important role in the transformation of inflammation into CRC, and both are critical to cellular signal transduction and constantly activated in cancer by various abnormal changes including epigenetics. The NF-κB and STAT3 signals contribute to the microenvironment for tumorigenesis through secretion of a large number of pro-inflammatory cytokines and their crosstalk in the nucleus makes it even more difficult to treat CRC. Compared with gene mutation that is irreversible, epigenetic inheritance is reversible or can be altered by the intervention. Therefore, understanding the role of epigenetic inheritance in the inflammation-cancer transformation may elucidate the pathogenesis of CRC and promote the development of innovative drugs targeting transformation to prevent and treat this malignancy. This review summarizes the literature on the roles of epigenetic mechanisms in the occurrence and development of inflammation-induced CRC. Exploring the role of epigenetics in the transformation of inflammation into CRC may help stimulate futures studies on the role of molecular therapy in CRC.

关键词： Colorectal cancer Inflammation DNA methylation Histone modification LncRNA MicroRNAs Epigenetics

Current situation and challenge of registry in China

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Frontiers of Medicine 2014年第3期8卷 294-299页

作者： Yang Zhang Yuji Feng Zhi Qu Yali qi Siyan Zhan Department of Epidemiology and Biostatistics School of Public Health Peking University Health Science Centre Beijing 100191 China Pfizer Investment Co. Ltd. Beijing 100010 China Department of Epidemiology School of Public Health Beihua University Jilin 132001China

Increasing emphasis has been placed on registries for an organized system used in developing clinical research to improve health care. China has sufficient data that can be applied broadly, but the heterogeneity and irregularity of registries limit their applicability. This article aims to describe the status of registries in China and the related challenges. Patient registries for observational studies were retrieved from the International Clinical Trials Registry to quantitatively evaluate the number of comparatively high-quality registries in China. A literature search was also performed to provide support and updates. A total of 64 patient registries were retrieved from *** using disease, product, and health service as criteria. The sample sizes ranged from 15 to 30 400, with only 12 registries marked as completed. This article describes and compares the detailed information in many aspects. The efficient use of registries has already made considerable progress in China; however, registries still require standardization, high-quality transition, and coordinated development.

关键词： Chinese registry study patient registries observational study

TST: Threshold Based Similarity Transitivity Method in Collaborative Filtering with Cloud Computing

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Tsinghua Science and Technology 2013年第3期18卷 318-327页

作者： Feng Xie Zhen Chen Hongfeng Xu Xiwei Feng qi Hou Department of Automation Research Institute of Information Technology and Tsinghua National Laboratory for Information Science and Technology (TNList) Tsinghua University Research Institute of Information Technology and Tsinghua National Laboratory for Information Science and Technology (TNList) Tsinghua University Department of Computer Science and Technologies and Tsinghua National Laboratory for Information Science and Technology (TNList) Tsinghua University Department of Electronic Engineering and Tsinghua National Laboratory for Information Science and Technology (TNList) Tsinghua University

Collaborative filtering solves information overload problem by presenting personalized content to individual users based on their interests, which has been extensively applied in real-world recommender systems. As a class of simple but efficient collaborative filtering method, similarity based approaches make predictions by finding users with similar taste or items that have been similarly chosen. However, as the number of users or items grows rapidly, the traditional approach is suffering from the data sparsity problem. Inaccurate similarities derived from the sparse user-item associations would generate the inaccurate neighborhood for each user or item. Consequently, its poor recommendation drives us to propose a Threshold based Similarity Transitivity （TST） method in this paper. TST firstly filters out those inaccurate similarities by setting an intersection threshold and then replaces them with the transitivity similarity. Besides, the TST method is designed to be scalable with MapReduce framework based on cloud computing platform. We evaluate our algorithm on the public data set MovieLens and a real-world data set from AppChina （an Android application market） with several well-known metrics including precision, recall, coverage, and popularity. The experimental results demonstrate that TST copes well with the tradeoff between quality and quantity of similarity by setting an appropriate threshold. Moreover, we can experimentally find the optimal threshold which will be smaller as the data set becomes sparser. The experimental results also show that TST significantly outperforms the traditional approach even when the data becomes sparser.

关键词： cloud computing recommender systems big data collaborative filtering data mining similarity transitivity machine learning mapReduce android applications

Comparison of the Typical Metallogenic Systems in the North Slope of the Tongbai-East qinling Mountains and its Geologic Implications

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Acta Geologica Sinica(English Edition) 2009年第2期83卷 396-410页

作者： ZHANG Jing CHEN Yanjing qi Jinping GE Jun State Key Laboratory of Geological Process andMineral Resources China University of GeosciencesBeijing 100083 China Key Laboratory of Metallogenic Dynamics Guangzhou Institute of Geochemistry the Chinese Academy of Sciences Guangzhou 510640 China

The Tongbai-East qinling Mountains, an important part of the Central orogenic belt, is one of the most important metallogenic belts in China and contains lots of orogenic-type and VMS-type （Volcanogenic Massive Sulfide type） metallogenic systems. The Dahe and Shuidongling VMS-type Cu-Zn deposits, located in the Erlangping Group in Tongbai and East qinling Mountains, respectively, show similar geological and geochemical features. The Huoshenmiao Formation in the East qinling region and the Liushanyan Formation in the Tongbai region are spilite-keratophyre sequences occurring in the western and eastern sides of the Nanyang Basin, respectively, and are interpreted to be equivalent to each other. The orogenic-type Au-Ag deposits can be subdivided into two styles; namely, fault- or structure-controlled （e.g. Yindonggou） and stratabound （e.g. Poshan）. The Poshan and Yindongpo orogenic-type Au-Ag deposits, whose ore bodies are strictly hosted in carbonaceous strata in the Tongbai Mountains, show obvious stratabound characteristics. Their ore-fluids are enriched in K^＋ and SO^2-4 and are regarded as K^＋-SO^2-4 types. The Pb-isotope ratios of sulfides of the ores are extremely uniform and significantly different from those of the tectonostratigraphic terranes of the qinling orogens except for the ore-hosting strata of the Waitoushan Formation. The Yindonggou and Xuyaogou orogenic Au-Ag deposits in the East qinling Mountains, whose ore bodies are hosted in the faults cutting the hosting strata or granite body, show fault-controlled characteristics. Their ore-fluids belong to the Na^＋-Cl^- type. The Pb-isotope ratios of sulfides of ores are similar to those of the northern qinling orogenic belt. The Waitoushan Formation, dominated by carbonaceous sericite-rich schists and only occurring in Tongbai region, should be detached from the Erlangping Group, which occurs both in the western and eastern sides of the Nanyang Basin. Future ore exploration in the Tongbai-East qinling Moun

关键词： Erlangping Group Orogenic-type deposit Tongbai-East qinling Mountains VMS-typedeposit Waitoushan Formation

Anticorrosion Performance of Carbon Steel in 55% LiBr Solution Containing PMA/SbBr_3 Inhibitor

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Journal of Iron and Steel Research International 2006年第4期13卷 56-60页

作者： HU Xian-qi LIANG Cheng-hao HUANG Nai-bao School of Chemical Engineering Dalian University of Technology Dalian 116012 Liaoning China Electromechanics and Materials Engineering College Dalian Maritime University Dalian 116026 Liaoning China

The anticorrosion performance of carbon steel in 55 % LiBr solution containing PMA/SbBr3 inhibitor was studied by weight-loss tests, electrochemical measurements and surface analysis. In 55 %LiBr＋PMA/SbBr3 solution, corrosion rates of carbon steel at 145 ℃, 175℃, 190℃ and 240℃ are 18.32μm·a^-1 , 27.68μm·a^-1, 53.58μm·a^-1 and 73. 78μm·a^-1 , respectively. PMA/SbBr3 inhibitor may inhibit the corrosion of carbon steel in 55% LiBr solution effectively. Especially, it shows an excellent corrosion inhibition performance at high temperature. Both anodic and cathodic reactions of carbon steel may be inhibited by PMA/SbBr3 inhibitor, so it may be classified as mixed inhibitor. In 55%LiBr＋PMA/SbBr3 solution, the apparent activation energy of the corrosion reaction of carbon steel is 29. 61 kJ·mol^-1. The corrosion inhibition mechanism of PMA/SbBr3 is suggested as follows： PMA has the effect of inhibiting hydrogen evolution and a strong oxidizing property; Sb^3＋ also exhibits oxidizing properties, and can exist stably with PMA in LiBr solutions; the passive film comprising Fe2O3 and antimony formed on carbon steel surface may prevent Brfrom diffusing into the metal surface due to the synergistic effect of PMA and Sb^3＋ ; As a result, the anticorrosion performance of carbon steel may be improved by PMA/SbBr3 inhibitor in 55% LiBr solution.

关键词： carbon steel lithium bromide corrosion inhibitor

A biomimetic gradient porous cage with a micro-structure for enhancing mechanical properties and accelerating osseointegration in spinal fusion

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Bioactive Materials 2023年第5期23卷 234-246页

作者： Cheng-qi Jia Zhen Zhang Shi-qi Cao Tian-Jiao Wang Hai-Chao Yu Wen-Xiang Wang Bo-Min Guo Xiong-Ying qiu Yong-Gang You Fan-qi Hu Jun Zhao Xue-Song Zhang Medical School of Chinese PLA Beijing100853China Department of Orthopedics Chinese PLA General HospitalBeijing100853China Department of Orthopedics of TCM Clinical Unit 6th Medical CenterChinese PLA General HospitalBeijing100853China Research Institute of Aerospace Special Materials and Processing Technology Beijing100074China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190China Academy of Military Medical Sciences Academy of Military SciencesBeijing100080China University of Chinese Academy of Sciences Beijing100049China

Objectives:Spinal fusion is a widely employed treatment of patients with degenerative disc disease,in which a cage is used to replace the disc for spinal *** it often fails for insufficient mechanical strength and poor ***,we designed a polyether-ether-ketone(PEEK)/tantalum(Ta)composite cage with a biomimetic gradient porous micro-structure,simultaneously enhancing mechanical properties and accelerating osseointegration in spinal *** and methods:In the study,based on the mechanical performances of PEEK and osteogenic potential of Ta,and the three-dimensional(3D)structures of cuttlebone and vertebra,the cages were respectively 3D printed by pure PEEK,PEEK with 5 wt%Ta(PEEK/Ta-5),PEEK with 10 wt%Ta(PEEK/Ta-10)and PEEK with 15 wt%Ta(PEEK/Ta-15),then verifiedin vitroand in sheep cervical fusion model ***:Vertebral Gyroid structure PEEK/Ta-15 cage exhibited superior mechanical properties than Cuttlebone-like structure PEEK/Ta-15 cage,closer to the cervical ***,PEEK/Ta-15 cage with higher Ta microparticles in PEEK provided a biomimetic gradient porous micro-structure with higher surface energy,guiding cell biological behavior,promoting new bone penetration,and accelerating osseointegrationin vivo.Conclusion:In conclusion,the study designed a biomimetic gradient porous cage with a micro-structure for enhancing mechanical properties,accelerating osseointegration and forming an anatomical lock in the fusion segment through composites,mechanical efficiency,surface extension,and pores.

关键词： Biomimetic Porous Composite Osseointegration Spinal fusion