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Interaction effect of nitrogen form and planting density on plant growth and nutrient uptake in maize seedlings

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Journal of Integrative Agriculture 2019年第5期18卷 1120-1129页

作者： WANG Peng WANG Zhang-kui sun Xi-chao MU Xiao-huan CHEN Huan CHEN Fan-jun Yuan Li-xing mi Guo-hua Department of Plant Nutrition College of Resources and Environmental SciencesChina Agricultural University

High planting density is essential to increasing maize grain ***,single plants suffer from insufficient light under high planting ***(NH_4^+)assimilation consumes less energy converted from radiation than nitrateIt is hypothesized that a mixed NO_3~–/NH_4^+supply is more important to improving plant growth and population productivity under high *** planting *** plants were grown under hydroponic conditions at two planting densities(low density:only).A significant interaction effect was found between planting density and N form on plant *** to nitrate only,75/25NO_3~–/NH_4^+increased per-plant biomass by 44%under low density,but by 81%under high *** with 75/25NO_3~–/NH_4^+increased plant ATP,photosynthetic rate,and carbon amount per plant by 31,7,and 44%under low density,respectively,but by 51,23,and 95%under high ***,carbon level per plant under 75/25NO_3~–/NH_4^+was improved,which increased leaf area,specific leaf weight and total root length,especially for high planting density,increased by 57,17 and 63%,***,under low density,75/25NO_3~–/NH_4^+increased nitrogen uptake rate,while under high density,75/25NO_3~–/NH_4^+increased nitrogen,phosphorus,copper and iron uptake *** increasing energy use efficiency,an optimum NO_3~–/NH_4^+ratio can improve plant growth and nutrient uptake efficiency,especially under high planting *** summary,an appropriate supply of NH_4^+in addition to nitrate can greatly improve plant growth and promote population productivity of maize under high planting density,and therefore a mixed N form is recommended for high-yielding maize management in the field.

关键词： maize planting density NO3^-/NH4^+ ratio carbon nutrient uptake root morphology

A humidity resistant and high performance triboelectric nanogenerator enabled by vortex-induced vibration for scavenging wind energy

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Nano Research 2022年第4期15卷 3246-3253页

作者： Yan Wang Tianyu Chen Shuowen sun Xiangyu Liu Zhiyuan Hu Zhenhui Lian Long Liu Qiongfeng Shi Hao Wang Jianchun mi Tongming Zhou Chengkuo Lee minyi Xu Dalian Key Lab of Marine micro/Nano Energy and Self-powered System Marine Engineering CollegeDalian Maritime UniversityDalian 116026China Center for Intelligent Sensors and MEMS(CISM) National University of Singapore Engineering Drive 3 Singapore 117576Singapore3 College of EngineeringPeking UniversityBeijing 100871China School of Civil Environmental and Mining EngineeringThe University of Western AustraliaWA 6009Australia

Wind energy is a promising renewable energy source for a low-carbon *** study is to develop a fully packaged vortexinduced vibration triboelectric nanogenerator(VIV-TENG)for scavenging wind *** VIV-TENG consists of a wind vane,internal power generation unit,an external frame,four springs,a square cylinder and a circular *** internal power generation unit consists of polytetrafluoroethylene(PTFE)balls,a honeycomb frame and two copper *** from most of the previous wind energy harvesting TENGs,the bouncing PTFE balls are fully packaged in the square *** distinct design separates the process of contact electrification from the external environment,and at the same time avoids the frictional wear of the ordinary wind energy harvesting *** corresponding VIV parameters are investigated to evaluate their influence on the vibration behaviors and the energy *** state of the VIV-TENG corresponds to the high output performance from the *** distinct,robust structure ensures the full-packaged VIV-TENG can harvest wind energy from arbitrary directions and even in undesirable weather *** study proposes a novel TENG configuration for harvesting wind energy and the VIV-TENG proves promising powering micro-electro-mechanical appliances.

关键词： vortex-induced vibration wind energy triboelectric nanogenerator self-powered

Radical innovation breakthroughs of biodegradation of plastics by insects:history,present and future perspectives

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 127-165页

作者： Shan-Shan Yang Wei-min Wu Federica Bertocchini Mark Eric Benbow Suja P.Devipriya Hyung Joon Cha Bo-Yu Peng Meng-Qi Ding Lei He Mei-Xi Li Chen-Hao Cui Shao-Nan Shi Han-Jun sun Ji-Wei Pang Defu He Yalei Zhang Jun Yang Deyi Hou De-Feng Xing Nan-Qi Ren Jie Ding Craig S.Criddle State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China Department of Civil and Environmental Engineering William&Cloy Codiga Resource Recovery CenterStanford UniversityStanfordCA 94305USA Plasticentropy rue Thiers 28Reims 51100France Department of Entomology and Department of Osteopathic Medical Specialties Michigan State UniversityEast LansingMI 48824USA School of Environmental Studies Cochin University of Science and TechnologyKochi 682022India Department of Chemical Engineering Pohang University of Science and TechnologyPohang 37673Republic of Korea School of Environmental Science and Engineering Tongji UniversityShanghai 200092China China Energy Conservation and Environmental Protection Group CECEP Talroad Technology Co.Ltd.Beijing 100096China School of Ecological and Environmental Sciences East China Normal UniversityShanghai 200241China Research Institute for Frontier Science Beihang UniversityBeijing 100191China School of Environment Tsinghua UniversityBeijing 100084China

Insects damaging and penetrating plastic packaged materials has been reported since the *** innovation breakthroughs of plastic biodegradation have been initiated since the discovery of biodegradation of plastics by Tenebrio molitor larvae in 2015 followed by Galleria mellonella in *** we review updated studies on the insect-mediated biodegradation of *** biodegradation by insect larvae,mainly by some species of darkling beetles(Tenebrionidae)and pyralid moths(Pyralidae)is currently a highly active and potentially transformative area of *** the past eight years,publications have increased explosively,including discoveries of the ability of different insect species to biodegrade plastics,biodegradation performance,and the contribution of host and microbiomes,impacts of polymer types and their physic-chemical properties,and responsible enzymes secreted by the host and gut *** date,almost all major plastics including polyethylene(PE),polypropylene(PP),polyvinyl chloride(PVC),polyethylene terephthalate(PET),polyurethane(PUR),and polystyrene(PS)can be biodegraded by *** and ten other insect species representing the Tenebrionidae and Pyralidae *** biodegradation processes are symbiotic reactions or performed by synergistic efforts of both host and gut-microbes to rapidly depolymerize and biodegrade plastics with hourly *** digestive ezymens and bioreagents screted by the insects play an essential role in plasatic biodegradation in certain species of Tenebrionidae and Pyralidae *** research on the insect itself,gut microbiomes,transcriptomes,proteomes and metabolomes has evaluated the mechanisms of plastic biodegradation in *** conclude this review by discussing future research perspectives on insect-mediated biodegradation of plastics.

关键词： Plastics Biodegradation Insects Gut microbiomes Enzymes

Overexpression of the M2 isoform of pyruvate kinase is an adverse prognostic factor for signet ring cell gastric cancer

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World Journal of Gastroenterology 2012年第30期18卷 4037-4043页

作者： Jae Yun lim sun Och Yoon So Young Seol Soon Won Hong Jong Won Kim Seung Ho Choi Jae Yong Cho Department of Medical Oncology Gangnam Severance Cancer HospitalYonsei University College of MedicineSeoul 135-720South Korea Department of Pathology Gangnam Severance Cancer HospitalYonsei University College of MedicineSeoul 135-720South Korea Department of Surgery Gangnam Severance Cancer HospitalYonsei University College of MedicineSeoul 135-720South Korea

AIM:To investigate M2 isoform of pyruvate kinase(PKM2) expression in gastric cancers and evaluate its potential as a prognostic biomarker and an anticancer ***:All tissue samples were derived from gastric cancer patients underwent curative gastrectomy as a primary *** and pathological information were obtained from the medical *** expression microarray data from 60 cancer and 19 noncancer gastric tissues were analyzed to evaluate the expression level of PKM2 *** microarrays were constructed from 368 gastric cancer *** was used to measure PKM2 expression and PKM2 positivity of cancer was determined by proportion of PKM2-positive tumor cells and staining *** between PKM2 expression and the clinicopathological factors was evaluated and the correlation between PKM2 and cancer prognosis was ***:PKM2 mRNA levels were increased more than 2-fold in primary gastric cancers compared to adjacent normal tissues from the same patients(log transformed expression level:7.6 ± 0.65 vs 6.3 ± 0.51,P might be an adverse prognostic factor for signet-rin

关键词： Gastric cancer M2 isoform of pyruvate kinase Biomarker Signet ring cell carcinoma Prognosis

N-polar InGaN nanowires: breaking the efficiency bottleneck of nano and micro LEDs

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Photonics Research 2022年第2期10卷 587-593页

作者： Xianhe Liu Yi sun Yakshita Malhotra Ayush Pandey Ping Wang Yuanpeng Wu Kai sun Zetian mi Department of Electrical Engineering and Computer Science University of MichiganAnn ArborMichigan 48109USA Guangzhou Institute of Technology Xidian UniversityGuangzhou 510555China Department of Materials Science and Engineering University of MichiganAnn ArborMichigan 48109USA

The efficiency of conventional quantum well light-emitting diodes(LEDs) decreases drastically with reducing areal size. Here we show that such a critical size scaling issue of LEDs can be addressed by utilizing N-polar In Ga N nanowires. We studied the epitaxy and performance characteristics of N-polar In Ga N nanowire LEDs grown on sapphire substrate by plasma-assisted molecular beam epitaxy. A maximum external quantum efficiency-11% was measured for LEDs with lateral dimensions as small as 750 nm directly on wafer without any packaging. The effect of electron overflow and Auger recombination on the device performance is also studied. This work provides a viable approach for achieving high-efficiency nano and micro LEDs that were not previously possible.

关键词： sapphire nanowires polar

竞争政策、营商环境与小微企业成长——基于《反垄断法》实施的准自然实验

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南开经济研究 2024年第7期 84-101页

作者：白雅洁孙伟增高雅中央财经大学经济学院 102200 南京审计大学联合研究院 211815 中国电子信息产业发展研究院 100081

《反垄断法》作为竞争政策的重要内容之一,为营造公平竞争的市场环境提供了基本保障。本文基于2007—2014年全国税收调查数据实证考察了《反垄断法》对小微企业成长的影响。研究结果显示,《反垄断法》的实施显著降低了区域性的行政垄断... 详细信息

《反垄断法》作为竞争政策的重要内容之一,为营造公平竞争的市场环境提供了基本保障。本文基于2007—2014年全国税收调查数据实证考察了《反垄断法》对小微企业成长的影响。研究结果显示,《反垄断法》的实施显著降低了区域性的行政垄断程度和市场垄断程度,改善了小微企业的营商环境,通过减轻税收负担、改善融资环境、降低行政管理成本和营业成本以及扩大商业信用规模等途径促进小微企业成长。异质性分析表明,《反垄断法》对不享有政府政策偏向的小微企业、所属行业市场垄断程度更高及产品可贸易性较低的小微企业发展的促进作用更加显著。进一步研究表明,《反垄断法》的实施显著提升了小微企业的地区创业活跃度,增加了小微企业对地区的税收贡献。本文的研究结论为全面理解竞争政策的经济效应和促进小微企业健康成长提供了政策依据。

关键词：反垄断法营商环境小微企业行政垄断市场垄断

Complete Solution of sun Tracking for Heliostat

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Communications in Theoretical Physics 2006年第1期45卷 165-166页

作者： CHEN Ying-Tian lim Boon-Han lim Chern-Sing Department of Astronomy and Applied Physics University of Science and Technology of China Hefei 230026 China

A general solution of sun tracking for an arbitrarily oriented heliostat towards an arbitrarily located target on the earth is published. With the most general form of solar tracking formulae, it is seen that the used azimuthelevation, spinning-elevation tracking formulae etc. are the special cases of it. The possibilities of utilizing the general solution and its significance in solar energy engineering are discussed.

关键词： solar tracking azimuth-elevation spinning-elevation optical aberration heliostat

Inhibition of matrix metalloproteinases expression in human dental pulp cells by all-trans retinoic acid

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International Journal of Oral Science 2014年第3期6卷 150-153页

作者： Jin Man Kim Sang Wook Kang Su-mi Shin Duck Su Kim Kyong-Kyu Choi Eun-Cheol Kim sun-Young Kim Department of Conservative Dentistry School of Dentistry Kyung Hee University Department of Maxillofacial Tissue Regeneration School of Dentistry Kyung Hee University

All-trans retinoic acid（ATRA） inhibits matrix metalloproteinase（MMP）-2 and MMP-9 in synovial fibroblasts, skin fibroblasts,bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells（HDPCs）. The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA（mRNA） expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction（PCR）, respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol？L21ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs,which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.

关键词： all-trans retinoic acid human dental pulp cell matrix metalloproteinase zymography

Distribution and Hydrogeochemical Characteristic of High Iodine Groundwater in Oasis Zone in the Tarim Basin in Xinjiang， P.R. China

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Journal of Earth Science 2022年

作者： Ying sun Yinzhu Zhou Jinlong Zhou Yanyan Zeng Yuanyuan Ji mi Lei Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention Center for Hydrogeology and Environmental Geology China Geological Survey Xinjiang Agricultural Professional Technological College Xinjiang Hydrology and Water Resources Engineering Research Center College of Water Conservancy and Civil Engineering， Xinjiang Agricultural University

Groundwater is the main water supply source in the Tarim Basin in China. Endemic disease caused by high iodine (I) groundwater in the Tarim Basin was reported previously. Therefore， it is crucial to systematically identify the distribution and genesis of groundwater I. Based on hydrochemical analysis of 717 groundwater samples collected in 2015-2018， spatial distribution and hydrogeochemistry characteristic of high I groundwater in different aquifers were analyzed. Results showed that groundwater I ranged between 100.00 μg/L) accounted for 7.25% of the total samples. Horizontally， groundwater I significantly increased from recharge zone (RZ) to transition zone (TZ) and to evaporation zone (EZ). Vertically， groundwater in shallow confined aquifer (SCA) had the greatest I concentration， followed by single-structure phreatic aquifer (SSPA)， phreatic aquifer in confined groundwater area (PACGA)， while groundwater in deep confined aquifer (DCA) generally had low I concentration. Groundwater I enrichment in SSPA was mainly affected by organic matter (OM) decomposition and that in SCA was mainly affected by evaporite mineral dissolution， OM decomposition under alkaline environment. While I enrichment in groundwater of PACGA was restrained under neutral environment. Lacustrine sedimentary environment was crucial for I enrichment in groundwater. Besides， fine-grained lithology of aquifer， smooth topographic slope， shallow buried depth of groundwater， weak alkaline and reducing environment， reductive dissolution of iron oxide/hydroxide minerals and OM decomposition were advantageous to I enrichment in groundwater.

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