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Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela h.nrik J.Persson Magnus Ekstrom Sean P.healey Zhiqiang Yang Joh.n holmgren Eva Lindberg Kenneth.nystrom Emanuele Papucci Patrik Ulvdal h.ns OleØrka Erik næsset Zh.ngyang hou håkan Olsson Ronald E.McRoberts Department of Forest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental Sciences and natural Resource Management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguish.ng between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

Crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria M.Manhas A.K.Bedyal Ankush Vij h.C.Swart Vinay Kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brigh.ness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Accuracy of tree mapping based on h.nd-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-hernández Cristóbal Ordóñez Tiago de Conto Felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using h.nd-held laser scanning(hLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on hLS under differ-ent ph.nology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the hLS data and to assess the influence of ph.nology wh.n converting 3D data into tree-level attrib-utes(DBh,height and volume).The hLS-based workflow was robust at isolating tree positions and recognizing stems despite ch.nges in ***-six percent of all pairs matched below 65 *** DBh,ph.nology barely altered *** observed a strong agreement wh.n comparing hLS-based tree height *** values exceeded 2 m wh.n comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).hLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed ph.nology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

In situ synthesis of graphitic-C3n4 nanosheet hybridized n-doped TiO2 nanofibers for efficient photocatalytic h2 production and degradation

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nano Research 2015年第4期8卷 1199-1209页

作者： Ch.ng h.n Yingde wang Yongpeng Lei bing Wang nan Wu Qi Shi Qiong Li Science and Technology on Advanced Ceramic Fibers and Composites Laboratory National University of Defense Technology Changsha 410073 China College of Materials Science and Engineering Wuhan Textile University Wuhan 430074 China College of Basic Education National University of Defense Technology Changsha 410073 China State Key Laboratory ofLow-Dimensiona/Quantum Physics and Department ofChemistry Tsinghua University Beijing 100084 China

Graphitic carbon nitride nanosheets （g-C3n4 nSs） hybridized nitrogen doped titanium dioxide （n-TiO2） nanofibers （GCn/nT nFs） have been synthesized in situ via a simple electrospinning process combined with a modified heat-etch.ng method. The prepared GCn/nT nFs were characterized by a variety of methods and their photocatalytic activities were evaluated by hydrogen （h2） production from water splitting and degradation of rhodamine B in aqueous solution. It was found that the GCn/nT nFs have a mesoporous structure, composed of g-C3n4 nSs and n-doped TiO2 crystallites. The g-C3n4 nSs synthesized after heat-etch.ng were found to be embedded in, and covered, the hybrid nFs to form stable interfaces. The partial decomposition of g-C3n4 releases its nitrogen content which eventually gets doped into the nearby TiO2 skeleton. The GCn/nT nFs give a high photocatalytic h2 production rate of 8,931.3 μmol·h^-1·g^-1 in aqueous meth.nol solution under simulated solar light. Such a highly efficient photocatalytic perfor- mance can be ascribed to the combined effects of g-C3n4 nSs and n-doped TiO2 with enh.nced light absorption intensity and improved electron transport ability. Also, the large surface area of the mesoporous nFs minimizes light reflection on the surface and provides more surface-active sites. This work highlights the potential of quasi-one dimensional hybrid materials in the field of solar energy conversion.

关键词： photocatalyst graphitic carbon nitride titanium oxide nanofiber hydrogen production

检测铁离子和肼的双功能荧光探针的合成与应用

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分析化学 2024年第6期52卷 809-827页

作者：端宁丁乐媛邓兵杨绍祥北京工商大学轻工科学技术学院

以6-甲氧基-2-乙酰萘为原料，通过两步反应方法合成了一种新的席夫碱荧光探针DFFh，采用核磁共振氢谱（1h.nMR）、碳谱(13C nMR)和高分辨质谱（hRMS）表征其结构，并考察了其光谱性质。在乙醇-水（EtOh-h2O,1:4,V/V）体系中，探针DFFh中... 详细信息

以6-甲氧基-2-乙酰萘为原料，通过两步反应方法合成了一种新的席夫碱荧光探针DFFh，采用核磁共振氢谱（1h.nMR）、碳谱(13C nMR)和高分辨质谱（hRMS）表征其结构，并考察了其光谱性质。在乙醇-水（EtOh-h2O,1:4,V/V）体系中，探针DFFh中的4-羟基苯胺部分与Fe3+按摩尔比1:1络合后，在386 nm处的荧光强度明显下降；在二甲基亚砜-水（DMSO-h2O,9:1,V/V,ph=5）体系中，少量肼（n2h4）可诱导探针DFFh酚对氨基苯酚部分的肼解，同时n2h4和探针DFFh中的α,β-不饱和羰基发生环化加成反应，具有比率型荧光识别特性。基于上述原理，实现了对Fe3+和n2h4的灵敏检测。加入Fe3+后，探针DFFh溶液的发光强度略有降低；同时，随着n2h4浓度增大，探针DFFh溶液由无色变为黄棕色，两者检测互不干扰。探针对Fe3+和n2h4具有较好的灵敏度和选择性，检出限（LOD,3σ）分别为34.0 nmol/L和30.0 nmol/L。采用此探针检测不同水样中Fe3+和n2h4的含量，回收率分别在96.5%～102.3%和98.1%～103.0%之间，表明探针DFFh可用于实际水样中Fe3+和n2h4含量的检测。

关键词：双功能荧光探针铁离子肼水样

来源：博看期刊

Superior antibody and membrane protein‑specific T‑cell responses to CoronaVac by intradermal versus intramuscular routes in adolescents

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World Journal of Pediatrics 2024年第4期20卷 353-370页

作者： Jaime S.Rosa Duque Samuel M.S.Ch.ng Carolyn A.Coh.n Daniel Leung Xiwei Wang Xiaofeng Mu Yuet Ch.ng Tsun Ming Lau Manni Wang Wenyue Zh.ng Yanmei Zh.ng howard h.W.Wong Leo C.h.Tsang Sara Chaothai Tsz Ch.n Kwan John K.C.Li Karl C.K.Ch.n Leo L.h.Luk Jenson C.h.ho Wing Yan Li Amos M.T.Lee Jennifer h.Y.Lam Sau Man Ch.n Wilfred h.S.Wong Issan Y.S.Tam Masashi Mori Sophie A.Valkenburg Malik Peiris Wenwei Tu Yu Lung Lau Department of Paediatrics and Adolescent Medicine The University of Hong KongHong KongChina School of Public health The University of Hong KongHong KongChina hKU‑Pasteur Research Pole School of Public HealthThe University of Hong KongHong KongChina Research Institute for Bioresources and Biotechnology Ishikawa Prefectural UniversityNonoichiJapan Department of Microbiology and Immunology Peter Doherty Institute for Infectionand ImmunityUniversity of MelbourneMelbourneVICAustralia Center for Immunology and Infection C2i Hong KongChina

Background Optimising the immunogenicity of COVID-19 vaccines to improve their protection against disease is *** dosing by intradermal(ID)administration has been shown to be equally immunogenic as intramuscular(IM)administration for several vaccines,but the immunogenicity of ID inactivated whole severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)at the full dose is *** study(nCT04800133)investigated the superiority of antibody and T-cell responses of full-dose CoronaVac by ID over IM administration in *** Participants aged 11–17 years received two doses of IM or ID vaccine,followed by the 3rd dose 13–42 days *** and cellular immunogenicity outcomes were measured post-dose 2(IM-CC versus ID-CC)and post-dose 3(IMCCC versus ID-CCC).Doses 2 and 3 were administered to 173 and 104 adolescents,*** Spike protein(S)immunoglobulin G(IgG),S-receptor-binding domain(RBD)IgG,S IgG Fcγreceptor IIIa(FcγRIIIa)-binding,SnM[sum of individual(S),nucleocapsid protein(n),and membrane protein(M)peptide pool]-specific interleukin-2(IL-2)+CD4^(+),SnM-specific IL-2^(+)CD8^(+),S-specific IL-2^(+)CD8^(+),n-specific IL-2^(+)CD4^(+),n-specific IL-2^(+)CD8^(+)and M-specific IL-2^(+)CD4^(+)responses fulfilled the superior and non-inferior criteria for ID-CC compared to IM-CC,whereas IgG avidity was *** ID-CCC,S-RBD IgG,surrogate virus neutralisation test,90%plaque reduction neutralisation titre(PRnT90),PRnT50,S IgG avidity,S IgG FcγRIIIa-binding,M-specific IL-2^(+)CD4^(+),interferon-γ+CD8^(+)and IL-2^(+)CD8^(+)responses were superior and non-inferior to *** estimated vaccine efficacies were 49%,52%,66%and 79%for IM-CC,ID-CC,IM-CCC and ID-CCC,*** ID groups reported more local,mild adverse *** This is the first study to demonstrate superior antibody and M-specific T-cell responses by ID inactivated SARSCoV-2 vaccination and serves as the basis for future research to improve the

关键词： CoronaVac Coronavirus disease 2019 Immunity Intradermal Vaccine

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共同富裕:涓滴效应在中国的再检验

经济学动态 2024年第4期 12-32页

作者：郑新业肖寒韩奕中国人民大学应用经济学院 100872 中国社会科学院数量经济与技术经济研究所 100732

新近研究发现,多数国家经济增长的成果并不能通过市场机制从高收入群体惠及低收入群体,即“涓滴效应”并不显著。中国是否存在“涓滴效应”,以实现“先富带动后富”?本文使用2012—2018年的微观数据研究发现:高收入者人均实际可支配收... 详细信息

新近研究发现,多数国家经济增长的成果并不能通过市场机制从高收入群体惠及低收入群体,即“涓滴效应”并不显著。中国是否存在“涓滴效应”,以实现“先富带动后富”?本文使用2012—2018年的微观数据研究发现:高收入者人均实际可支配收入的增加显著降低了农村低收入群体的贫困概率,表明中国存在显著的“先富带动后富”现象。机制研究表明,财政转移支付和国有企业在其中起着关键作用:政府通过建立亲贫财政体系,在不盲目扩张债务的前提下将来自高收入者的税收转化为对低收入者的转移支付和公共服务,从而带动低收入者脱贫;为电力、铁路交通、通信网络提供基础设施的国有企业通过提供服务满足高收入者的需求进行盈利,同时以提供普遍服务或降价的方式为低收入群体提供基础设施,保证其获得基础设施接入的权利,从而带动低收入者脱贫。本文为理解我国“先富带动后富”的机制和实现共同富裕的路径提供了新的思考和证据。

关键词：共同富裕涓滴效应减贫中央转移支付国有企业

Advanced Oxidation Wastewater Treatment of 3 LPS of an Avocado Sauce Company,at Morelia,Michoacan,Mexico

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Journal of Environmental Science and Engineering(A) 2024年第5期13卷 151-155页

作者： Alfonso Espitia-Cabrera Francisco Javier Barrón-Santos JoséL.Méndez-Antonio héctor M.Alemán-Vásquez Omar G.Color-Vázquez Saneamiento y Planeación Ambiental Azcapotzalco CDMX 02200México Energy Department Metropolitan Autonomous University Azcapotzalco CampusCDMX 02200Mexico Environmental System Engineering Department Environmental Engineering AcademyNational School of Biological SciencesNational Polytechnic InstituteCiudad de MéxicoCDMX 07738México Planta Congeladora y Empacadora nacional Morelia 58190MichoacánMéxico

This paper describes the wastewater treatment of 3 liters per second of capacity of discharges of capacity,from the avocado washed,as well as the production of avocado *** were pretreated with a grease and oil trap and contained small amounts of oil and grease,dissolved and total solids,organic matter and trace of organic and inorganic compounds from the vitamins and minerals of *** treatment train is located in an small surface and the train is integrated with coagulation in line with alumina in a static mixer,rapid filtration in two steps,double advanced oxidation with ozone and heterocyclic photocatalysis with a nanofilm of zinc oxide as,photocatalyzer and final adsorption of refractory compounds with activated *** treated wastewater meets the environmental regulation to urban sewerage discharges of the city,according to the results of a Mexican Certified Laboratory.

关键词： Wastewater primary treatment rapid filter performance static mixer

Structural Analysis for Qazzaz Metamorphic Core Complex,northwestern Arabian Shield,Saudi Arabia

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Acta Geologica Sinica(English Edition) 2024年第5期98卷 1187-1201页

作者： Mansour h.AL-hAShIM Osama M.K.KASSEM Department of Geology and Geophysics College of ScienceKing Saud University11451 RiyadhSaudi Arabia Department of Geology National Research CenterCairoEgypt

Identifying deformational mech.nisms and associated structures at various scales,ranging from regional-scale structures to microscopic fabric,is crucial for the assessment of tectonic ***-three samples were taken from the Qazzaz metamorphic core complex to estimate the finite strain for felsic and mafic *** samples included gneisses rocks,monzogranite,and metavolcano-sedimentary rocks for both the Thalbah and Bayda *** the Rf/j and Fry methods,the axial ratios(XZ)range about 2.20 to 7.10 and 1.90 to 9.10,*** various rock units,the strain measurements show moderate to highly *** of the observed samples show shallow WnW dipping along a n to WnW trend of finite strain(X).The short axes(Z)based to be subvertical foliation related with a subhorizontal *** results demonstrate that contacts generated at semi-brittle to ductile deformation and that the strain of magnitude has the same value for different lithologic *** concluded that nappe generation in orogens results from pure shear deformation.

关键词： Finite strain metamorphic core complex Qazzaz area Saudi Arabia