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Solar spectral conversion based on plastic films of lanthanide-doped ionosilicas for photovoltaics:Down-shifting layers and luminescent solar concentrators

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Journal of Rare Earths 2020年第5期38卷 531-538页

作者： M.A.Cardoso S.F.H.Correia A.R.Frias H.M.R.Goncalves R.F.P.Pereira S.C.Nunes M.Armand P.S.André v.de zea bermudez R.A.S.Ferreira department of Physics and CICECO-Aveiro Institute of Materials University of Aveiro3810-193AveiroPortugal department of Chemistry and CQ-vR University of Tras-os-Montes e Alto Douro5000-801Vila RealPortugal Instituto de Telecomunicacoes University of Aveiro3810-193AveiroPortugal REQUIMTE Instituto Superior de Engenharia do Porto4200-072PortoPortugal Chemistry Centre and Chemistry department University of Minho4710-057BragaPortugal CICS-Health Sciences Research Center and Chemistry department University of Beira Interior6201-001CovilhaPortugal Electrical Energy Storage department CIC EnergiguneParque Tecnologico de AlavaMinano01510Spain department of Electrical and Computer Engineering Instituto de TelecomunicacoesInstituto Superior TecnicoUniversidade de Lisboa1049-001LisbonPortugal

The mismatch between the photovoltaic(Pv)cells absorption and the solar irradiance on earth is one of the major limitations towards more efficient Pv energy *** aspect was addressed by downshifting the solar irradiance on Earth through luminescent down-shifting layers based on lanthanidedoped surface-functionalized ionosilicas(ISs)embedded in poly(methyl methacrylate)(PMMA)coated on the surface of commercial Si-based Pv *** IS-PMMA hybrid materials exhibit efficient solar radiation harvesting(spectral overlap of^9.5×10^19 photons/(s·m2))and conversion(quantum yield^52%).The direct solar radiation and the down-shifted radiation are partially guided and lost through total internal reflection to the layer edges being unavailable for Pv conversion of the coated Pv *** tuning the down-shifting layer thickness,it also acts as luminescent solar concentrator enabling the collection of the guided radiation by flexible Pv cells applied on the borders of the down-shifting layer leading to an enhancement of the Pv energy conversion from^5%(in the case of the single-use of the luminescent down-shifting layer)to^13%comparing with the bare Pv *** overall electrical output of the device resulted in an absolute external quantum efficiency increase of^32%for the optimized Eu^3+-based films in the Uv spectral region(compared with the bare Pv.device,which is among the best values reported so far).

关键词： Ionosilicas Lanthanides Photovoltaics Luminescent solar concentrators Down-shifting layers Silicon photovoltaic cells

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NF-κB promotes the stem-like properties of leukemia cells by activation of LIN28B

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World Journal of Stem Cells 2018年第4期10卷 34-42页

作者： Jianbiao Zhou Jing-Yuan Chooi Ying Qing Ching Jessie Yiying Quah Sabrina Hui-Min Toh Yvonne Ng Tuan zea Tan Wee-Joo Chng Cancer Science Institute of Singapore National University of Singapore department of Medicine Yong Loo Lin School of MedicineNational University of Singapore department of Hematology-Oncology National University Cancer Institute

AIM To examine whether nuclear factor kappa B(NF-κB) activity regulates LIN28 B expression and their roles in leukemia stem cell(LSC)-like properties. METHODS We used pharmacological inhibitor and cell viability assays to examine the relation between NF-κB and LIN28 B. Western blot and q RT-PCR was employed to determine their protein and m RNA levels. Luciferase reporter was constructed and applied to explore the transcriptional regulation of LIN28 B. We manipulated LIN28 B level in acute myeloid leukemia(AML) cells and investigated LSC-like properties with colony forming and serial replating assays. RESULTS This study revealed the relationship between NF-κB and LIN28 B in AML cells through drug inhibition and overexpression experiments. Notably,inhibition of NF-κB by pharmacological inhibitors reduced LIN28 B expression and decreased cell proliferation. We demonstrated that NF-κB binds to the-819 to-811 region of LIN28 B promoter,and transcriptionally regulates LIN28 B expression. LIN28 B protein was significantly elevated in NFκB1 transfected cells compared to vector control. Importantly,ectopic expression of LIN28 B partially rescued the self-renewal capacity impaired by pharmacological inhibition of NF-κB activity. CONCLUSION These results uncover a regulatory signaling,NF-κB/LIN28 B,which plays a pivotal role in leukemia stem cell-like properties and it could serve as a promising intervening target for effective treatment of AML disease.

关键词： Nuclear factor kappa B LIN28B Leukemia stem cell Acute myeloid leukemia

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Impact of Chiapanecan Handicrafts

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Journal of Modern Accounting and Auditing 2018年第6期14卷 333-342页

作者： Karla Liliana Haro-zea Karla S. Basurto Gutiérrez Blanca H. Morales vázquez Omar A. Flores Laguna Meritorious Autonomous University of Puebla Mexico University of Montemorelos Mexico

The purpose of this research is to study the perception of Chiapanecan handicrafts as an element of sustainable competitive advantage in the State of Chiapas, Mexico, mainly due to the tourism. Mexican handicrafts contribute to 20.3% of the Gross Domestic Product （GDP） of the cultural sector, that is, 0.6% of the National GDP. This research is quantitative, descriptive, and transversal. The sample selection was made for convenience so certain criteria could be met. In total, 70 tourists were surveyed in the handicraft commerce area. For the data retrieval, an instrument with the “Sustainability SWOT” （sSWOT） was designed, which consists of eight dimensions （trends, environmental challenges, threats, opportunities, strengths, weaknesses, which to prioritize, and where to act）. The instrument consists of 22 items with a single Likert scale ranging from 1 to 5 （1 = Null to 5 = Excellent）. The study showed that 54.29% of the tourists who visit Chiapas perceive that handicrafts have a regular impact on the small producer’s quality of life, while the remaining 45.71% point out that the impact is greater.

关键词： strategy competitiveness handicrafts competitive advantage sustainability and innovation

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Effects of Tillage and Crop Residue Management on Maize Yields and Net Returns in the Central Mexican Highlands Under Drought Conditions

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Pedosphere 2014年第4期24卷 476-486页

作者： R.ROMERO-PEREZGROvAS N.vERHULST D.de LA ROSA v.HERNáNdeZ M.MAERTENS J.deCKERS B.GOvAERTS International Maize and Wheat Improvement Center(CIMMYT) P.O.Box 6-641Mexico D.F.06600(Mexico) department of Earth and Environmental Sciences University of LeuvenCelestijnenlaan 200 ELeuven 3001(Belgium) Mathematics Research Center(CIMAT) Jalisco S/NValencianaGuanajuatoMexico CP 36240(Mexico)

In the subtropical highlands of Central Mexico, where the main crop is maize （zea mays）, the conventional practice （CP） involves tillage, monoculture and residue removal, leading to soil degradation and unsustainable use of natural resources and agricultural inputs. Conservation agriculture （CA） has been proposed as a viable alternative in the region, based on reduction in tillage, retention of adequate levels of crop residues and soil surface cover and use of crop rotation. This study began in 2009 when the highlands of Central Mexico suffered from a prolonged drought during vegetative maize growth in July-August, providing an opportunity for the on-farm comparison of CA with CP under severe drought conditions which 21 climate change models projected to become more frequent. Under dry conditions, CA resulted in higher yields and net returns per hectare as early as the first and second years after adoption by farmers. As an average of 27 plots under farmers＇ management in 2009, the maize yields were 26% higher under CA （6.3 t ha-1） than under CP （5.0 t ha-l）. 2010 was close to a normal year in terms of rainfall so yields were higher than in 2009 for both practices; in addition, the yield difference between the practices was reduced to 19% （6.8 t ha-1 for CA vs. 5.7 t ha-1 for CP）. When all the 2009 and 2010 observations were analyzed in a modified stability analysis, CA had an overall positive effect of 3 838 Mexican Pesos ha-1 （320 $US ha-1） on net return and 1.3 t ha-1 on yield. After only one to two years of adoption by farmers on their fields, CA had higher yields and net returns under dry conditions that were even drier than those predicted by the analyzed 21 climate change models under a climate change scenario, emission scenario A2.

关键词： climate change conservation agriculture conventional practice emission scenario modified stability analysis

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Can the grains offer each other helping hands?Convergent molecular mechanisms associated with domestication and crop improvement in rice and maize

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Molecular Plant 2022年第5期15卷 793-795页

作者： Ravi v.Mural James C.Schnable University of Nebraska-Lincoln LincolnNEUSA

The grasses,Poaceae,are an extraordinarily ecologically success-ful clade,with more than 10000 described extant *** grasses include more than 30 domesticated grain crops,ranging from maize(zea mays),rice(Oryza sativa),and wheat(Triticum aes-tivum),which are collectively responsible for 50%of all calories consumed by humans around the world,to minor and orphan crops such as teff(Eragrostis tef),pearl millet(Pennisetum glaucum),proso millet(Panicum milaceum),and Job's tears(Coix lacryma-jobi)(Glémin and Bataillon,2009).Domestication of grain crops from their wild relatives involved a common suite of phenotypic changes,including loss of seed shattering,loss of dormancy,and increased apical dominance,which are collectively referred to as"domestication syndrome"(Glémin and Bataillon,2009).

关键词： sativa crops collective

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Nitrogen Recommendations for Summer Maize in Northern China Using the N_min Test and Rapid Plant Tests

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Pedosphere 2005年第2期15卷 246-254页

作者： LIUXue-Jun JUXiao-Tang CHENXin-Ping ZHANGFu-Suo v.ROMHELD CollegeofResourcesandenvironmentalSciences KLPSI-MOEChinaAgriculturalUniversity2YuanmingyuanWestRoadBeijing100094（China） InstituteofPlantNutrition UniversityofHohenheimStuttgart459703（Germany）

A field experiment with a split-plot design was carried out at Dongbeiwang Farm in Beijing Municipality to establish reliable N fertilizer recommendation indices for summer maize (zea mays L.) in northern China using the soil Nmin (mineral N) test as well as the plant nitrate and SPAD (portable chlorophyll meter readings) tests. The results showed that Nmin sollwert (NS) 60 kg N ha-1 at the third leaf stage and N rate of 40 to 120 kg N ha-1 at the tenth leaf stage could meet the N requirement of summer maiz…

关键词： N balance N recommendation soil and plant tests zea mays L

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Soil Organic Matter and Grain Yield of Rainfed Maize in Luvisols of Campeche, México

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Agricultural Sciences 2019年第12期10卷 1602-1613页

作者： Juan Medina-Méndez víctor H. volke-Haller José I. Cortés-Flores Arturo Galvis-Spínola María de J. Santiago-Cruz Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias Campo Experimental Edzná Campeche México Colegio de Postgraduados Texcoco México

The organic matter is an important soil component, due its favorable effects on soil physical and chemical properties and, by consequence, on crop yields. So, the objective of this work was quantify the changes through the time of soil organic matter in rainfed maize (zea mays L.) system, in a period of 30 years of continuous crop and in relation to system of natural vegetation system, and also the effects of these changes on the crop yield, in Luvisols soils of State of Campeche, México. In production cycle of 2004, 53 farmer plots in rainfed maize system of different land use time and five sites of forest natural vegetation system were sampled for soil, to quantify physical and chemical properties of soil, and it was taken data about climate, system management and crop yield. The data were analiced by regression analysis, considered the organic matter as function of land use time and factors of soil and management of system, and the crop yield as function of soil organic matter and factors of soil, climate and management of system. The soil organic matter diminished from 5.68% in forest natural vegetation system to 3.59% after 16 - 30 years of cultivation, and the soil annual incorporation of vegetative mulch (weeds and stubble of maize) increased the organic matter from 0.14% after 1 - 5 years to 0.46% after 16 - 30 years of cultivation. Without fertilization, the diminution of soil organic matter caused 907 kg⋅ha−1 less of maize yield, and the fertilization with 200 kg⋅ha−1 of diamonic phosphate (36 kg⋅N⋅ha−1 and 92 kg P2O5 ha−1) increased the maize yield 1224 kg⋅ha−1 after 1 - 5 years and 1421 kg⋅ha−1 after 16 - 30 years of cultivation, but not compensed less maize yield of 711 kg⋅ha−1 due the diminution of soil organic matter.

关键词： zea mays L. Annual Crops Forest Natural vegetation Land Use Time Soil Properties

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自动生成的腹部CT影像生物标志物对无症状成年人未来严重骨质疏松性骨折的机会性预测

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国际医学放射学杂志 2020年第6期 738-738页

作者：朱春梅 P.J.Pickhardt P.M.Graffy R.zea S.J.Lee J.Liu v.Sandfort department of Radiology University of Wisconsin School of Medicine & Public Health

摘要腹部CT扫描提供的人体组织数据有潜能对未来骨折的高危人群进行机会性识别。目的对平扫CT数据应用自动化的骨、肌肉和脂肪工具以评估其预测严重骨质疏松性

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Effects of Plant Residue decomposition on Soil N Availability,Microbial Biomass and β-Glucosidase Activity During Soil Fertility Improvement in Ghana

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Pedosphere 2019年第5期29卷 608-618页

作者： Samuel T. PARTEY Robert B. Z0UGM0RE Naresh v. THEvATHASAN Richard F. PREZIOSI CGI AR CCAFS West Africa ProgramInternational Crops Research Institute for the Semi-Arid Tropics (ICRISAT)Bamako B.P. Box 320 (Mali) School of Environmental Sciences University of GuelphGuelph NIG 2W1 (Canada) Faculty of Life Sciences The University of ManchesterManchester M13 9PL (UK)

With limited use of inorganic fertilizers on smallholder farms,plant residues could be viable alternatives for soil fertility *** study was conducted to determine how residue quality and decomposition of nine plant species influence soil N availability,microbial biomass,andβ-glucosidase activity during soil fertility *** differences in N concentration were found among the species,ranging from 12.2 g kg-1 in zea mays to 39.2 g kg-1 in Baphia *** C/N ratio was the highest in ***(34.4),whereas lignin and polyphenol concentrations were the greatest in Acacia *** highest decomposition rate(0.251%per day)occurred in Tithonia diversifolia,and the lowest in ***,Albizia zygia,***,and ***,with the half-lives of 28-56 *** 80%and 89%of N,P,K,Ca,and Mg were released from *** in 7 d,compared with over 70%retention in ***,***,and *** decomposition and nutrient release half-lives of Gliricidia sepium,Leucaena leucocephala,Azadirachta indica,and Senna spectabilis were less than 14 *** mineral N,microbial biomass,andβ-glucosidase activity increased under all treatments,with *** having the greatest *** N mineralization occurred in all of the species throughout the experiment,an initial N immobilization was recorded in the ***,***,***,and *** treatments for up to 14 *** and nutrient release rates,mineral N,soil microbial biomass,andβ-glucosidase activity were dependent on residue quality,and P and lignin levels,the lignin/N ratio,and the(lignin+polyphenol)/N ratio had the most significant effects(P≤0.05).

关键词： leguminous species litter quality microbial activity N mineralization nutrient release organic matter

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Study of the Rooting Potential of Humic and Fulvic Acids,Amino Acids and Seaweed Extracts in Maize Culture

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Journal of Agricultural Science and Technology(B) 2019年第3期9卷 160-164页

作者： Anderson Souza de Jesus Francisco Camargo de Oliveira Nilva Teresinha Teixeira victor Augusto Pezoti Silvério department of Research and development Juma-Agro2370Victor Acierini AvenueMogi GuacuSPCEP 13.849-106Brazil department of Plants Nutrition Helio Vergueiro Leite AvenueEspirito Santo do PinhalSPCEP 13.990-000Brazil

Corn is a commodity of great expression. For high yields, it is necessary that plants have availability of resources to develop and rely on vigorous root systems and adequate initial development. The inclusion in crops of products with humic and fulvic acids, seaweed and amino acids, is among resources. The objective was to present the results of a study conducted, the effect of the use of amino acids, humic and fulvic acids and seaweed associated with plant nutrients in the initial development of corn (zea mays L.) cultivated in pots. The trial, with corn cultivate Bandeirante, was conducted outdoors in the department of Plant Nutrition of the UniPinhal Agronomic Engineering Course, in Espirito Santo do Pinhal—SP (latitude 22°06′57″ N, longitude 46°40′58″ W and altitude of 892.7 m), from March to April 2018, in randomized blocks with eight treatments and four replicates. The products studied were applied in two periods: v1 and v3, by drench. Each plot consisted of a 20 L plastic container containing soil (classified as Acrisols-World Reference Base/FAO), corrected for fertility. At 55 d after germination were evaluated: root mass and length and culm diameter. All the results were treated statistically (analysis of variance and Duncan test at 5%). The treatments applied in the trial benefited the root development and culm diameter;humic and fulvic acids + N, P, Mo and Co + humic and fulvic acids + N, P and K, when considering all the criteria, was shown to be the most efficient.

关键词： Organic acids metabolism synergism

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