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Neural Regeneration Research 2020年第8期15卷 1473-1474页

作者： leonardo Acuna Natalia S.Corbalán Rita Raisman-Vozari Consejo Nacional de investigaciones Científicas y Técnicas(CONiCET) Universidad Nacional de Salta(UNSa)SaltaArgentina institut du Cerveau et de la Moelleépinière(iCM) Inserm U 1127CNRS UMR 7225Sorbonne UniversitéParisFrance

The World Health Organization has predicted that neurodegenerative diseases affecting the motor function will become the second most prevalent cause of death in the next 20 *** therapies can result from three main sources:synthetic compounds,natural products,and existing ***’s disease(PD)is a common neurodegenerative disease affecting 1–3%of the adult population over 50 years of age *** is initially characterized by the death of dopaminergic neurons in the substantia nigra pars compact and later by the widespread loss of nondopaminergic neurons,including those in the cortex.

关键词： inflammation death drugs

Variable retention harvesting: conceptual analysis according to different environmental ethics and forest valuation

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Ecological Processes 2019年第1期8卷 485-491页

作者： leonardo Galetto Carolina Torres Guillermo J.Martínez Pastur Departamento de Diversidad Biológica y Ecología FCEFyNUniversidad Nacional de Córdoba(UNC)Vélez Sarsfield 16115000 CórdobaArgentina instituto Multidisciplinario de Biología Vegetal(iMBiV) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Vélez Sarsfield 16115000 CórdobaArgentina Centro Austral de investigaciones Científicas(CADiC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 2009410 UshuaiaTierra del FuegoArgentina.

Background:Conceptual clarity is important to attain precise communication of scientific knowledge and to implement appropriate technological and policy *** concepts referring to forest management are widely used by decision-makers,regardless of their *** the scientific and methodological issues of forestry practices are frequently discussed in the literature,their normative dimensions are rarely ***,linguistic uncertainty increases when different environmentally ethical perspectives and ways of valuing forests are *** objective was to compare different conceptualizations on the silvicultural systems suggested for forest management and the implications they have for *** have conceptually contrasted highintensity forestry practices with variable retention harvesting,considering different environmentally ethical perspectives and forest valuation ***:Clear boundaries between clear-cutting,selective logging,and variable retention harvesting can be evidenced when different ethical points of view and alternatives in the human-nature relationships are *** have found a variety of definitions of variable retention harvesting that can be analyzed under different ethical *** contrasting views on variable retention harvesting can be evidenced if nature is considered to be purely at human’s service or if it is conceptualized as humans co-inhabiting with *** latter position implies that the maintenance of ecological,evolutionary,and historical processes supported by unmanaged forest stands is a crucial step for forest management proposals based on variable retention ***:Forestry practices that are focused on forest yields and that misinterpret functional uncertainty of forest functioning would be ***,forestry with variable retention harvesting could imply good yields with reasonable conservation management in some contexts,while it could be unacce

关键词： Environmental ethical perspectives Consequentialism Deontological ethics Virtue ethics Policy options for forest and biocultural conservation

Central role of the LEAFY COTYLEDON1 transcription factor in seed development

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Journal of integrative Plant Biology 2019年第5期61卷 564-580页

作者： leonardo Jo Julie M.Pelletier John J.Harada Department of Plant Biology and Plant Biology Graduate Group University of CaliforniaDavis USA

Seed development is a complex period of the flowering plant life *** fertilization,the three main regions of the seed,embryo,endosperm and seed coat,undergo a series of developmental processes that result in the production of a mature seed that is developmentally arrested,desiccated,and metabolically *** processes are highly coordinated,both temporally and spatially,to ensure the proper growth and development of the *** transcription factor,LEAFY COTYLEDON1(LEC1),is a central regulator that controls several aspects of embryo and endosperm development,including embryo morphogenesis,photosynthesis,and storage reserve ***,LEC1 regulates distinct sets of genes at different stages of seed *** its critical importance for seed development,an understanding of the mechanisms underlying LECi's multifunctionality is only beginning to be *** studies describe the roles of specific transcription factors and the hormones,gibberellic acid and abscisic acid,in controlling the activity and transcriptional specificity of LEC1 across seed ***,studies indicate that LEC1 acts as a pioneer transcript!on factor to promote epigenetic reprogramming during *** this review,we discuss the mechanisms that enable LEC1 to serve as a central regulator of seed development.

关键词： Seed development flowering plant seed development

How the Antimicrobial Peptides Kill Bacteria:Computational Physics insights

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Communications in Computational Physics 2012年第3期11卷 709-725页

作者： Licui Chen Lianghui Gao Weihai Fang leonardo Golubovic College of Chemistry Beijing Normal UniversityBeijing 100875China Physics Department West Virginia UniversityMorgantownWest Virginia 26506-6315USA

in the present article,coarse grained Dissipative Particle Dynamics simulation with implementation of electrostatic interactions is developed in constant pressure and surface tension ensemble to elucidate how the antimicrobial peptidemolecules affect bilayer cellmembrane structure and kill *** find that peptideswith different chemical-physical properties exhibit differentmembrane obstructing *** molecules can destroy vital functions of the affected bacteria by translocating across their membranes via worm-holes,or by associating with membrane lipids to form hydrophilic cores trapped inside the hydrophobic domain of the *** the latter model,the affected membranes are strongly buckled,in accord with very recent experimental observations[*** et al.,***.,5(2010),pp.280-285].

关键词： Antimicrobial peptide bilayer membrane dissipative particle dynamics

Combining fatty acid amide hydrolase (FAAH) inhibition with peroxisome proliferator-activated receptor (PPAR) activation: a new potential multi-target therapeutic strategy for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2020年第1期15卷 67-68页

作者： leonardo Brunetti Antonio Laghezza Fulvio Loiodice Paolo Tortorella Luca Piemontese Dipartimento di Farmacia-Scienze del Farmaco Università degli Studi di Bari "Aldo Moro"

Alzheimer’s disease(AD)is a widespread pathology described for the first time by Alois Alzheimer in *** can be classified as a neurodegenerative disease consisting in a progressive loss of memory and cognitive functions,whose prevalence is estimated to grow due to the increasing life expectancies all over the *** date,the only treatments available for this disease are symptomatic and no actual effective cure is *** main effect of the drugs commonly used in therapeutic protocols is to temporarily delay the onset of the disease and to slightly improve the patients’cognitive capabilities(Piemontese,2017)(Figure 1).

关键词： Alzheimer drugs treatment

Aspects of forest restoration and hydrology:the hydrological function of litter

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Journal of Forestry Research 2022年第2期33卷 543-552页

作者： Luara Castilho Pereira leonardo Balbinot Marcelle Teodoro Lima Julieta Bramorski Kelly Cristina Tonello Hydrology in Forest Ecosystems Lab.(Hidrolef) Department of Environmental SciencesFederal University of São Carlos(UFSCar)SorocabaSão PauloBrazil Hydrology in Forest Ecosystems Lab.(Hidrolef) Department of Environmental SciencesFederal University of Amapá(UNIFAP)MacapáAmapáBrazil

Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado *** study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the *** retention capacity and effective water retention capacity of litters(unstructured materials,branches and leaves)in the field were monitored on a monthly *** litter accumulation at 46 years was significantly higher than that of the other succession *** litter mass was significantly higher than that of leaves and *** 46-year stage had the highest water holding capacity in the leaf fraction,followed by unstructured material and *** the water holding capacity was lower in the oldest resto-ration,this site showed the highest efficiency under field *** process was quickly reestablished,as the 11-year restoration showed results closer to that for the 46-year stage in comparison to the area at 8 ***,passive restoration plays a key role in soil water mainte-nance due to the influence of litter in Cerrado *** and the imminent need of restoring degraded sites,highlight the need for further studies focused on bet-ter understanding of the process of forest restoration and its temporal effect on soil water recovery dynamics.

关键词： Forest hydrology Litter interception Stemflow Cerrado Águas Perenes Forest Water holding capacity

Reflectivity and thickness analysis of epiretinal membranes using spectral-domain optical coherence tomography

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international Journal of Ophthalmology(English edition) 2016年第1期9卷 93-98页

作者： Ajay E.Kuriyan Delia cabrera DeBuc William E.Smiddy Department of Ophthalmology Bascom Palmer Eye InstituteMiller School of Medicine University of Miami

AiM：To compare thickness and reflectivity spectral domain optical coherence tomography（SD-OCT）findings in patients with idiopathic epiretinal membranes（ERMs）,before and after ERM peeling surgery,with normal controls.·METHODS：A retrospective study analyzing SD-OCTs of eyes with ERMs undergoing ERM peeling surgery by one surgeon from 2008 to 2010 and normal control ***-OCTs were analyzed using a customized algorithm to measure reflectivity and *** relationship between the SD-OCT findings and best corrected visual acuity（BCVA）outcomes was also studied.·RESULTS：Thirty-four ERM eyes and 12 normal eyes were *** eyes had high reflectivity and thickness of the group of layers from the internal limiting membrane（iLM）to the retinal pigment epithelium（RPE）and the group of layers from the iLM to the external limiting membrane（ELM）.The values of reflectivity of these two groups of layers decreased postoperatively,but were still higher than normal *** contrast,preoperative eyes had lower reflectivity of two10×15 pixel regions of interest（ROis）incorporating：1）ELM＋outer nuclear layer（ONL）and 2）photoreceptor layer（PRL）＋RPE,compared to *** values of reflectivity of these ROis increased postoperatively,but were still lower than normal controls.A larger improvement in BCVA postoperatively was correlated with a greater degree of abnormal preoperative reflectivity and thickness findings.·C ONCLUSiON：Quantitative differences in reflectivity and thickness between preoperative,postoperative,and normal SD-OCTs allow assessment of changes in the retina secondary to *** study identified hyperreflective inner retina changes and hyporeflective outer retina changes in patients with ***-OCT quantitative measures of reflectivity and/or thickness of specific groups of retinal layers and/or ROis correlate with improvement in BCVA.

关键词： epiretinal membranes optical coherencetomography reflectivity retina imaging vitrectomy

Learning the Mapping x→Σi=1^d xi^(2):the Cost of Finding the Needle in a Haystack

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Communications on Applied Mathematics and Computation 2021年第2期3卷 313-335页

作者： Jiefu Zhang leonardo Zepeda-Nunez Yuan Yao Lin Lin Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720USA Department of Mathematics University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Computational Research Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

The task of using the machine learning to approximate the mapping x→Σi=1^d xi^(2)with Xi∈[-1,1]seems to be a trivial *** the knowledge of the separable structure of the function,one can design a sparse network to represent the function very accurately,or even *** such structural information is not available,and we may only use a dense neural network,the optimization procedure to find the sparse network embedded in the dense network is similar to finding the needle in a haystack,using a given number of samples of the *** demonstrate that the cost(measured by sample complexity)of finding the needle is directly related to the Barron norm of the *** only a small number of samples are needed to train a sparse network,the dense network trained with the same number of samples exhibits large test loss and a large generalization *** control the size of the generalization gap,we find that the use of the explicit regularization becomes increasingly more important as d *** numerically observed sample complexity with explicit regularization scales as G(d^(2.5)),which is in fact better than the theoretically predicted sample complexity that scales as 0(d^(4)).Without the explicit regularization(also called the implicit regularization),the numerically observed sample complexity is significantly higher and is close to 0(d^(4.5)).

关键词： Machine learning Sample complexity Generalization error

Reproductive patterns in Araucaria araucana forests in the Andean range, Chile

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Ecological Processes 2024年第1期13卷 252-261页

作者： Sergio Donoso Karen Pe?a-Rojas Claudia Espinoza Carolain Badaracco Rómulo Santelices-Moya Antonio cabrera-Ariza Mediterranean Forests Laboratory Faculty of Forestry and Nature Conservation Centro Secano Faculty of Agricultural and Forestry Sciences Universidad Católica del Maule Maule Advanced Studies Research Center Vice-Rector's Office for Research and Postgraduate Studies Catholic University of Maule

Background Araucaria araucana is a mast species that presents a high variability in annual cone production. Researchers have recorded synchronization events in cone production in different populations, which allows the seed production to be concentrated, reducing the percentage of seeds consumed by different animal *** We sampled three populations located in the Andes Mountains, Araucanía Region, Chile. in 2004 we began the collection of data on cone production, for which we installed permanent plots（1200 m2each） at each location. We identified and labeled each female tree in each plot to monitor its cone production. in 2012 we selected a total of 30 trees near the plots to evaluate the number of seeds per cone. in each February from 2012 to 2014 we selected two mature cones and covered them with a porous mesh for subsequent collection and storage in March. At the beginning of June, we counted and weighed the seeds, determining the average weight, the number of seeds per cone, the germination capacity（GC）, and the germination speed（GS）.Results Cone production was synchronous across the three locations. We observed significant differences among the locations and years evaluated. The cones had fewer seeds in 2013（high production） compared to those in 2012（low production）, but their weights were similar. in 2014 the cones produced smaller seeds in fewer quantities. The difference between the years 2013 and 2014 resulted from the high-energy expenditure in 2013. Regarding GC and GS, there were significant differences among the three locations（GC: F = 45.41, p ighest values were observed in *** Both GC and GS are related to seed weight but not to the number of cones produced in a given year. These annual fluctuations in seed production are determining factors in the population dynamics of forest species. Our results allow a better understanding of the reproductive phenology of A. araucana and could hel

关键词： Seed weight Germination potential Masting species Sustainable use Dioecious species

Mo_(2)P Monolayer as a Superior Electrocatalyst for Urea Synthesis from Nitrogen and Carbon Dioxide Fixation:A Computational Study

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Energy & Environmental Materials 2024年第1期7卷 207-214页

作者： Dongxu Jiao Zhongxu Wang Yuejie Liu Qinghai Cai Jingxiang Zhao Carlos R.cabrera Zhongfang Chen College of Chemistry and Chemical Engineering and Key Laboratory of Photonic and Electronic Bandgap Materials Ministry of EducationHarbin Normal UniversityHarbin 150025China Modern Experiment Center Harbin Normal UniversityHarbin 150025China Heilongjiang Province Collaborative innovation Center of Cold Region Ecological Safety Harbin 150025China Department of Chemistry and Biochemistry The University of Texas at El PasoEl Paso TX 79968USA Department of Chemistry University of Puerto RicoRio Piedras CampusSan JuanPuerto Rico 00931USA

Urea synthesis through the simultaneous electrocatalytic reduction of N_(2)and CO_(2)molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production,in which the development of stable,highly efficient,and highly selective catalysts to boost the chemisorption,activation,and coupling of inert N_(2)and CO_(2)molecules remains rather ***,by means of density functional theory computations,we proposed a new class of two-dimensional nanomaterials,namely,transition-metal phosphide monolayers(TM_(2)P,TM=Ti,Fe,Zr,Mo,and W),as the potential electrocatalysts for urea *** results showed that these TM_(2)P materials exhibit outstanding stability and excellent metallic ***,the Mo_(2)P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier(0.35 eV)for C-N coupling,low limiting potential(-0.39 V),and significant suppressing effects on the competing side *** outstanding catalytic activity of the Mo_(2)P monolayer can be ascribed to its optimal adsorption strength with the key^(*)NCON species due to its moderate positive charges on the Mo active *** findings not only propose a novel catalyst with high-efficiency and high-selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.

关键词： C-N coupling density functional theory Mo_(2)P monolayer urea synthesis