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International Journal of Coal Science & Technology 2014年第2期1卷 235-240页

作者： Lewis M.Gomez Fredy Colpas-Castillo roberto fernandez-maestre Department of Electrical Engineering and Department of Chemistry University of Southern CaliforniaLos Angeles 90089USA Grupo de Carboquı´mica Programa de Quı´micaUniversidad de CartagenaCampus de San PabloCartagenaColombia

A subbituminous coal was oxidized with air at 150℃on a fixed bed for 4 h and xanthated with carbondisulfide in a basic solution,at 30 or 5-10℃.This xanthated coal was evaluated for the removal of Hg^(2+)and Cd^(2+)from 7,000 mg/L aqueous solutions;metal concentrations were detemmined by atomic absorption spectrometry.The ionexchange of the xanthated coal was compared against those of the original subbituminous coal,a sulfonated subbituminouscoal,activated carbon,commercial activated carbon,and commercial synthetic resin.The commercial synthetic resinshowed the highest exchange capacity(concentration factor 98%)followed by the xanthated coal(concentration factor 96%).The retention of cadmium on the sulfonated subbituminous coal was lower(exchange capacity 0.56 meq/g)thanthat of xanthated coals(1.85±0.09 meq/g).Our xanthated coal showed a better Cd^(2+)removal(8l%o against 15%)than anon preoxidized 40-h-xanthated coal,which shows that oxidation of coal increased the amount of oxygenated groups whichenhanced xanthation.

关键词： lon exchange Heavy metals Adsorption Low rank coal Xanthated coal

Nitrogen addition delays the emergence of an aridity-induced threshold for plant biomass

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National Science Review 2023年第11期10卷 148-159页

作者： Hailing Li César Terrer Miguel Berdugo Fernando T.maestre Zaichun Zhu Josep Pe?uelas Kailiang Yu Lin Luo Jie-Yu Gong Jian-Sheng Ye State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems College of EcologyLanzhou University Department of Civil and Environmental Engineering Massachusetts Institute of Technology Instituto Multidisciplinar para el Estudio del Medio“Ramón Margalef ”Universidad de Alicante Institut de Biologia Evolutiva(CSIC-UPF) Departamento de Ecología Universidad de Alicante School of Urban Planning and Design Peking University Shenzhen Graduate SchoolPeking University CSIC Global Ecology Unit CREAF-CSIC-UAB CREAF Cerdanyola del Vallès High Meadows Environmental Institute Princeton University

Crossing certain aridity thresholds in global drylands can lead to abrupt decays of ecosystem attributes such as plant productivity, potentially causing land degradation and desertification. It is largely unknown,however, whether these thresholds can be altered by other key global change drivers known to affect the water-use efficiency and productivity of vegetation, such as elevated CO2and nitrogen(N). Using >5000 empirical measurements of plant biomass, we showed that crossing an aridity(1–precipitation/potential evapotranspiration) threshold of ～0.50, which marks the transition from dry sub-humid to semi-arid climates, led to abrupt declines in aboveground biomass(AGB) and progressive increases in root:shoot ratios, thus importantly affecting carbon stocks and their distribution. N addition significantly increased AGB and delayed the emergence of its aridity threshold from 0.49 to 0.55(P < 0.05). By coupling remote sensing estimates of leaf area index with simulations from multiple models, we found that CO2enrichment did not alter the observed aridity threshold. By 2100, and under the RCP 8.5 scenario, we forecast a 0.3% net increase in the global land area exceeding the aridity threshold detected under a scenario that includes N deposition, in comparison to a 2.9% net increase if the N effect is not considered. Our study thus indicates that N addition could mitigate to a great extent the negative impact of increasing aridity on plant biomass in drylands. These findings are critical for improving forecasts of abrupt vegetation changes in response to ongoing global environmental change.

关键词： aboveground biomass root:shoot ratios elevated CO2 nitrogen fertilization ecosystem threshold

Neoadjuvant immunotherapy in non-small-cell lung cancer:Times are changing—and fast

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World Journal of Clinical Oncology 2022年第9期13卷 758-761页

作者： Carlos Aguado Unai Jiménez maestre Xabier Mielgo-Rubio Department of Medical Oncology Hospital Universitario Clínico San CarlosMadrid 28040Spain Department of Thoracic Surgery Hospital Universitario CrucesBarakaldo 48903BizkaiaSpain Department of Medical Oncology Hospital Universitario Fundación AlcorcónAlcorcón 28922MadridSpain

Recent data from a phase 3 trial have shown that the addition of immunotherapy to neoadjuvant chemotherapy improves event-free survival in patients with nonsmall-cell lung cancer(NSCLC).This is the first positive phase 3 trial in this setting,although several phase 3 trials are currently investigating the efficacy of neoadjuvant and adjuvant immunotherapy in resectable NSCLC.

关键词： Neoadjuvant Immunotherapy NSCLC Perioperative Checkmate-816 nivolumab Chemo-immunotherapy

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打破干旱区土地退化与贫困的联结

Science Bulletin 2022年第24期67卷 2508-2512页

作者：吕楠傅伯杰 Mark Stafford-Smith Fernando T.maestre 程临海 State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China CSIRO Land&Water Canberra ACT 2601Australia Department of Ecology University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain Multidisciplinary Institute for Environment Studies“Ramon Margalef” University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain

Drylands cover approximately 41%of the global land surface and provide homes to more than two billion people. Collectively,drylands constitute the largest terrestrial biome on the planet,and despite their low productivity per land area compared to other ecosystems, they have a major impact on the ecological functioning and climate of our planet through carbon storage, albedo, dust production, and water cycling [1].

关键词： planet 土地退化 cycling

A MACHINE LEARNING APPROACH FOR MECHANISM SELECTION IN COMPLEX NEGOTIATIONS

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Journal of Systems Science and Systems Engineering 2018年第2期27卷 134-155页

作者： Reyhan Aydogan Ivan Marsa-maestre Mark Klein Catholijn M. Jonker Department of Computer Science Ozyegin University Istanbul Turkey reyhan Interactive Intelligence Group Delft University of Technology The Netherlands Department of Computer Engineering University of Alcala 28805 Alcala de Henares Madrid Spain ivan Interactive Center for Collective Intelligence Massachusetts Institute of Technology Cambridge USA

Automated negotiation mechanisms can be helpful in contexts where users want to reach mutually satisfactory agreements about issues of shared interest, especially for complex problems with many interdependent issues. A variety of automated negotiation mechanisms have been proposed in the literature. The effectiveness of those mechanisms, however, may depend on the charaeteristics of the underlying negotiation problem （e.g. on the complexity of participant＇s utility functions, as well as the degree of conflict between participants）. While one mechanism may be a good choice for a negotiation problem, it may be a poor choice for another. In this paper, we pursue the problem of selecting the most effective negotiation mechanism given a particular problem by （1） defining a set of scenario metrics to capture the relevant features of negotiation problems, （2） evaluating the performance of a range of negotiation mechanisms on a diverse test suite of negotiation scenarios, （3） applying machine learning techniques to identify which mechanisms work best with which scenarios, and （4） demonstrating that using these classification rules for mechanism selection enables significantly better negotiation performance than any single mechanism alone.

关键词： Automated negotiation mechanism selection scenario metrics

Stipa tenacissima Does not Affect the Foliar δ^(13)C and δ^(15)N of Introduced Shrub Seedlings in a Mediterranean Semi-arid Steppe

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Journal of Integrative Plant Biology 2006年第8期48卷 897-905页

作者： Fernando T.maestre Susana Bautista Jordi Cortina Departamento de Ecologia Universidad de AlicanteApartado de correos 9903080 AlicanteSpain Department of Biology Duke UniversityPhytotron BuildingScience DriveBox 90340DurhamNorth Carolina 27708-0340USA Centro de Estudios Ambientales del Mediterraneo C/ Charles Darwin 1446980 PaternaSpain

Recent studies have shown that the tussock grass Stipa tenacissima L. facilitates the establishment of late-successional shrubs, in what constitutes the first documented case of facilitation of woody plants by grasses. With the aim of increasing our knowledge of this interaction, in the present study we investigated the effects of S. tenacissima on the foliar δ13C, δ15N, nitrogen concentration, and carbon ： nitrogen ratio of introduced seedlings of Pistacia lentiscus L., Quercus coccifera L., and Medicago arborea L. in a semi-arid Mediterranean steppe. Six months after planting, the values of δ13C ranged between -26.9‰ and -29.6‰, whereas those of δ15N ranged between -1.9‰ and 2.7‰. The foliar C ： N ratio ranged between 10.7 and 53.5, and the nitrogen concentration ranged between 1.0% and 4.4%. We found no significant effect of the microsite provided by S. tenacissima on these variables in any of the species evaluated. The values of δ13C were negatively correlated with predawn water potentials in M. arborea and were positively correlated with relative growth rate in Q. coccifera. The values of δ15N were positively correlated with the biomass allocation to roots in the latter species. The present results suggest that the modification of environmental conditions in the are surrounding S. tenacissima was not strong enough to modify the foliar isotopic and nitrogen concentration of shrubs during the early stages after planting.

关键词： facilitation Medicago arborea Pistacia lentiscus Quercus coccifera stable isotopes steppe Stipa tenacissima.

Li2SnO3 branched nano- and microstructures with intense and broadband white-light emission

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Nano Research 2019年第2期12卷 441-448页

作者： Miguel Garcia-Tecedor Javier Bartolome David maestre Achim Trampert Ana Cremades Dpt. Fisica de Materials Facultad de CC. Fisicas Universidad Complutense de Madrid Madrid 28040 Spain Paul-Drude-Institut fur Festkorperelektronik Hausvogteiplatz 5-7 Berlin 10117 Germany Institute of Advanced Materials (INAM) Universitat Jaume I Castello 12006 Spain Dpt. Fisica de Materiales Facultad de CC. Ftsicas Universidad Complutense de Madrid Madrid 28040 Spain

Exploiting the synergy between microstructure, morphology and dimensions by suitable nanomaterial engineeri ng, can effectively upgrade the physical properties and material performances. Li2SnO3 elongated nano- and microstructures in form of belts, wires, rods and branched structures have been fabricated by a vapor-solid method at temperatures ranging from 700 to 900℃ using metallic Sn and Li2CO3 as precursors. The achievement of these new morphologies can face challenging applications for Li2SnO3, not only in the field of energy storage, but also as building blocks in optoelectronic devices. The micro? and nanostructures grown at 700 and 800℃ correspond to monoclinic Li2SnO3, while at 900℃ complex Li2S nO/SnO2 core-shell microstructures are grow n, as con firmed by X-ray diffractio n and Rama n spectroscopy. Transmission electron microscopy reveals structural disorder related to stacking faults in some of the branched structures, which is associated with the prese nee of the low-temperature phase of L12S nO3. The luminescent resp onse of these structures is domi nated by in tense emissi ons at 2, 2.5 and 3 eV, almost completely covering the whole range of the visible light spectrum. As a result, white-light emission is obtained without the need of phosphors or complex quantum well heterostructures. Enhanced functionality in applications such as in light-emitting devices could be exploited based on the high luminescenee intensity observed in some of the analysed Li2SnO3 structures.

关键词： lithium oxides white light emitters nanostructures luminescenee

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干旱区主导全球植被生产力增加趋势

Science Bulletin 2023年第2期68卷 224-232,M0004页

作者：王帅傅伯杰魏芳莉朴世龙 Fernando T.maestre Lixin Wang Wenzhe Jiao 刘焱序李琰李长嘉赵文武 State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Department of Ecology University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain Multidisciplinary Institute for Environment Studies“Ramon Margalef” University of AlicanteCarretera de San Vicente del RaspeigAlicante 03690Spain Department of Earth Sciences Indiana University-Purdue University IndianapolisIndianapolis IN 46202USA

旱区(drylands)是指年平均降雨量与潜在蒸散发之比小于0.65的区域,占全球陆地表面的42%,是最易受气候变化影响的地区之一.然而,目前关于旱区植被对气候变化的响应特征及其对全球变绿和陆地生态系统生产力变化的相对贡献仍不清楚.本研究... 详细信息

旱区(drylands)是指年平均降雨量与潜在蒸散发之比小于0.65的区域,占全球陆地表面的42%,是最易受气候变化影响的地区之一.然而,目前关于旱区植被对气候变化的响应特征及其对全球变绿和陆地生态系统生产力变化的相对贡献仍不清楚.本研究通过集成模型和遥感数据分析发现,旱区对全球变绿的贡献较小,仅占33%±15%,但却主导了全球植被生产力(GPP)增加趋势,贡献达65%±16%旱区植被光合利用效率升高是解释变绿与生产力增加不一致的主要原因.旱区光能利用率主要受土壤水分的影响,大气水汽压差作用不显著,而非旱区主要受大气水汽压差的影响,土壤水的作用有限.因此,需要强调使用不同的水分胁迫指标来预测不同区域植被生产力变化的重要性,这也有助于理解较长时间尺度上植被绿度与生产力之间的解耦关系.

关键词：光能利用率水汽压差气候变化影响植被生产力旱区潜在蒸散发相对贡献集成模型

A Variational Approach to Norm Attainment of Some Operators and Polynomials

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Acta Mathematica Sinica,English Series 2010年第12期26卷 2259-2268页

作者： María D.ACOSTA Jernimo ALAMINOS Domingo GARCA Manuel maestre Departamento de Anlisis Matemtico Universidad de Granada Departamento de Anlisis Matemtico Universidad de Valencia

If X is an Asplund space, then every uniformly continuous function on Bx＊ which is holomorphic on the open unit ball, can be perturbed by a w＊ continuous and homogeneous polynomial on X＊ to obtain a norm attaining function on the dual unit ball. This is a consequence of a version of Bourgain-Stegall＇s variational principle. We also show that the set of N-homogeneous polynomials between two Banach spaces X and Y whose transposes attain their norms is dense in the corresponding space of N-homogeneous polynomials. In the case when Y is the space of Radon measures on a compact K, this result can be strengthened.

关键词： Banach space variational principle operator polynomial holomorphic function

Functional leaf and size traits determine the photosynthetic response of 10 dryland species to warming

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Journal of Plant Ecology 2016年第6期9卷 773-783页

作者： Enrique Valencia JoséL.Quero Fernando T.maestre Departamento de Biología y Geología Física y Química InorgánicaEscuela Superior de Ciencias Experimentales y TecnologíaUniversidad Rey Juan CarlosC/Tulipán s/n28933 MóstolesSpain Departamento de Ingeniería Forestal Escuela Técnica Superior de Ingeniería Agronómica y de MontesUniversidad de Córdoba Campus de Rabanales CrtaN-IV km.396C.P.14071 CórdobaSpain

Aims Relatively few studies so far have assessed how ongoing global warming will affect the photosynthetic performance of dryland plant species.We evaluated the effects of warming on the photosynthetic rates of 10 species with contrasting functional attributes,and whether their functional traits modulated photosynthetic responses to warming.Methods A common garden experiment was conducted over 2 years with distinct environmental conditions(drier vs.wetter year).The experiment was designed as a randomized block design with two treatments:warming(control vs.~2.9℃ temperature increase)and species(Agropyron cristatum,Festuca ovina,Lygeum spartum,Medicago sativa,Plantago lanceolata,Psoralea bituminosa,Sanguisorba minor,Hedysarum coronarium,Dorycnium pentaphyllum and Phlomis herba-venti).We linked functional traits measurements with temporal variations in photosynthetic responses to warming.Important Findings In the drier year,warming increased photosynthetic rates at the beginning of the growing season,suggesting a modification in the growing period(earlier spring).In the wetter year,functional traits modulated photosynthetic responses to warming.Larger species with shorter leaves(e.g.M.sativa)had higher photosynthetic rates under warming compared to smaller species with larger leaves(e.g.F.ovina).Our results highlight the importance of(i)studying photosynthetic responses along different years and(ii)considering functional traits when evaluating photosynthetic responses to climate change,particularly in stressful environments such as drylands.

关键词： photosynthesis climate change Mediterranean functional traits open top chambers