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The method of residual‑based bootstrap averaging of the forecast ensemble

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Financial Innovation 2023年第1期9卷 991-1002页

作者： vera Ivanyuk Department of Data Analysis and Machine Learning Financial University49 Leningradsky ProspektMoscowRussia 125993

This paper presents an optimization approach—residual-based bootstrap averaging(RBBA)—for different types of forecast *** traditional residual-mean-square-error-based ensemble forecast averaging approaches,the RBBA method attempts to find optimal forecast weights in an ensemble and allows for their combi-nation into the most effective additive *** the RBBA method,all the different types of forecasts obtain the optimal weights for ensemble residuals that are statisti-cally optimal in terms of the fitness function of the *** studies have been conducted to demonstrate why and how the RBBA method *** experi-mental results based on the real-world time series of contemporary stock exchanges show that the RBBA method can produce ensemble forecasts with good generalization ability.

关键词： Forecast ensembles Time series Artificial neural networks

CD271 as a marker to identify mesenchymal stem cells from diverse sources before culture

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World Journal of stem Cells 2015年第2期7卷 470-476页

作者： María álvarez-Viejo Yolanda Menéndez-Menéndez jesús Otero-Hernández Unidad de Trasplantes Terapia Celulary Medicina RegenerativaAvenida de Roma s/nHospital Universitario Central de Asturias

Mesenchymal stem cells, due to their characteristics are ideal candidates for cellular therapy. Currently, in culture these cells are defined by their adherence to plastic, specific surface antigen expression and multipotent differentiation potential. However, the in vivo identification of mesenchymal stem cells, before culture, is not so well established. Pre-culture identification markers would ensure higher purity than that obtained with selection based on adherence to plastic. Up until now, CD271 has been described as the most specific marker for the characterization andpurification of human bone marrow mesenchymal stem cells. This marker has been shown to be specifically expressed by these cells. Thus, CD271 has been proposed as a versatile marker to selectively isolated and expand multipotent mesenchymal stem cells with both immunosuppressive and lymphohematopoietic engraftment-promoting properties. This review focuses on this marker, specifically on identification of mesenchymal stem cells from different tissues. Literature revision suggests that CD271 should not be defined as a universal marker to identify mesenchymal stem cells before culture from different sources. In the case of bone marrow or adipose tissue, CD271 could be considered a quite suitable marker; however this marker seems to be inadequate for the isolation of mesenchymal stem cells from other tissues such as umbilical cord blood or wharton's jelly among others.

关键词： Mesenchymal stem cells CD271 Lowaffinitynerve growth factor receptor p75 Bone marrow

Do non-target species visit feeders and water troughs targeting small game?A study from farmland spain using camera-trapping

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Integrative Zoology 2021年第2期16卷 226-239页

作者： JoséA.ARMENTEROs jesús CARO Carlos sÁNCHEZ-GARCÍA Beatriz ARROYO JoséA.PÉREZ Vicente RGAUDIOsO Emilio J.TIZADO Department of Animal Production Research Group on Game Species Breeding and ManagementUniversity of LeónLeónSpain Instituto de Investigación en Recursos Cinegéticos(IREC CSIC-UCLM-JCCM)Ciudad RealSpain Fundación Artemisan Ciudad RealSpain Department of Biodiversity and Environmental Management University of LeónPonferradaSpain

Provision of food and water is a widespread tool implemented around the world for the benefit of game and other wildlife,but factors affecting the use of food and water by non-target species are poorly *** evaluated visits to feeders and water troughs by non-game species using camera-traps in two separate areas of *** and water troughs were either“protected”(when surrounded by more than 50%of shrubs/forest)or“open”(in the opposite case).A total of 18948 photos from 5344 camera-trapping days depicted animals,and 75 species were *** and water troughs were visited by target species(partridges and lagomorphs,55.3%of visits)and non-target species(44.7%of visits).Among the latter,corvids were themost common(46.1%of visits),followed by rodents(26.8%),other birds(23.6%,mainly passerines),columbids(1.9%),and other species at minor *** highest proportion of visiting days to feeders and water troughs was from corvids(0.173)followed by otherbirds(0.109)and rodents(0.083);the lowest proportion was recorded for columbids(0.016).Use intensity and visit frequency of water troughs tripled that recorded in feeders,and visits to open feeders/troughs were approximately twice those to protected *** summary:feeders and water troughs targeting small game species are also used regularly by non-target ones;they should be set close to cover to optimize their use by non-target species that are not competitors of target species(though corvids may visit them);water availability should be prioritized where drought periods are expected.

关键词： camera-trapping feeding game species management watering wildlife

Emerging bisphenol a replacements(colour developers)in indoor dust from spain

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Emerging Contaminants 2019年第1期5卷 168-172页

作者： María jesús Duenas-Mas Ana Ballesteros-Gomez soledad Rubio Department of Analytical Chemistry Institute of Fine Chemistry and NanochemistryMarie Curie Building AnnexCampus of RabanalesUniversity of Cordoba14071CordobaSpain

Bisphenol A(BPA)and replacements,such as bisphenol s(BPs)and F(BPF)and other substitutes(BPsMAE,D-8 and TGsA)have been recently reported in thermal *** this study,BPA,BPs,BPF;BPs-MAE,D-8 and TGsA were analysed in indoor dust collected in spain from different microenvironments(living rooms,bedrooms,cars and offices).Levels were compared with those reported in our previous study(shops and other public microenvironments,where frequent use of thermal paper is expected).We investigated the differences between microenvironments,possible correlations between compounds and estimated the ingestion ***-MAE,D-8 and TGsA were present at levels up to 529,128 and 356 ng g^-1,respectively,in all the *** highest levels were measured in cars.

关键词： Bisphenol A Bisphenol F Bisphenol s BPs-MAE D-8 TGsA Indoor dust

same or different?Abstract relational concept use in juvenile bamboo sharks and Malawi cichlids

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Current Zoology 2021年第3期67卷 279-292页

作者： Theodora Fuss Leonie John vera schluessel Institute of Zoology Rheinische Friedrich-Wilhelms-University BonnMeckenheimer Allee 169Bonn53115Germany

sorting objects and events into categories and concepts is an important cognitive prerequisite that spares an individual the learning of every object or situation encountered in its daily ***,specific items are classified in general groups that allow fast responses to novel *** present study assessed whether bamboo sharks Chiloscyllium griseum and Malawi cichlids Pseudotropheus zebra can distinguish sets of stimuli(each stimulus consisting of two abstract,geometric objects)that meet two conceptual preconditions,i.e.,(1)"sameness"versus"difference"and(2)a certain spatial arrangement of both *** two alternative forced choice experiments,individuals were first trained to choose two different,vertically arranged objects from two different but horizontally arranged *** discriminations were followed by extensive transfer test *** tests using stimuli consisting of(a)black and gray circles and(b)squares with novel geometric patterns provided conflicting information with respect to the learnt rule"choose two different,vertically arranged objects",thereby investigating(1)the individuals'ability to transfer previously gained knowledge to novel stimuli and(2)the abstract relational concept(s)or rule(s)applied to categorize these novel *** results suggest that the level of processing and usage of both abstract concepts differed considerably between bamboo sharks and Malawi *** sharks seemed to combine both concepts-although not with equal but hierarchical prominence-pointing to advanced cognitive ***,Malawi cichlids had difficulties in discriminating between symbols and failed to apply the acquired training knowledge on new sets of geometric and,in particular,gray-level transfer stimuli.

关键词： visual concept learning spatial arrangement relational abstract concept Malawi cichlid bamboo shark

Point-of-care ultrasonography in geriatric medicine: usefulness for approaching infectious endocarditis diagnosis

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Journal of Geriatric Cardiology 2022年第12期19卷 1001-1002页

作者： Pablo solla Patricia Cancelo Eva López jesús de la Hera César Morís José Gutiérrez Geriatrics Department Geriatrics Clinical Management AreaHospital Monte NarancoOviedoSpain Health Research Institute of Asturias OviedoSpain Cardiology Department Cardiac AreaHospital Universitario Central de AsturiasOviedoSpain

Infective endocarditis has a high morbimortality rate,and delay in diagnosis and treatment is associated with a higher prevalence of *** clinical presentation is often atypical in older adults,and even when the classic symptoms are present,they may overlap with those of other conditions,making management more *** present the case of a nonagenarian in whom cardiac-centered point-of-care ultrasound facilitated real-time decision making and the diagnosis of mitral endocarditis.

关键词： diagnosis endocarditis mortality

IAs/IFRs and financial reporting quality:Lessons from the European experience

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China Journal of Accounting Research 2013年第4期6卷 247-263页

作者： vera Palea Department of Economics and statistics "Cognetti de Martiis" University of Torino

This paper discusses the effects of the adoption of IAs/IFRs in Europe on the quality of financial *** doing so,it adopts the perspective of stock market investors and focuses on value-relevance *** adoption of IAs/IFRs in Europe is an example of accounting standardization among countries with different institutional frameworks and enforcement *** allows investigating whether,and to what extent,accounting regulation per se can affect the quality of financial reporting and leads to convergence in financial *** is a key issue for standard setting purposes as IAs/IFRs have been adopted in very diverse countries all over the world,and many others are likely to adopt them in the near future.

关键词： Financial reporting quality IAs/IFRs Value-relevance European Regulation 1606/2002

How to Check If a Number Is Prime Using a Finite Definite Integral

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Journal of Applied Mathematics and Physics 2019年第2期7卷 364-380页

作者： jesús sánchez Independent Researcher Bilbao Spain

In the history of mathematics different methods have been used to detect if a number is prime or not. In this paper a new one will be shown. It will be demonstrated that if the following equation is zero for a certain number p, this number p would be prime. And being m an integer number higher than (the lowest, the most efficient the operation). . If the result is an integer, this result will tell us how many permutations of two divisors, the input number has. As you can check, no recurrent division by odd or prime numbers is done, to check if the number is prime or has divisors. To get to this point, we will do the following. First, we will create a domain with all the composite numbers. This is easy, as you can just multiply one by one all the integers (greater or equal than 2) in that domain. so, you will get all the composite numbers (not getting any prime) in that domain. Then, we will use the Fourier transform to change from this original domain (called discrete time domain in this regards) to the frequency domain. There, we can check, using Parseval’s theorem, if a certain number is there or not. The use of Parseval’s theorem leads to the above integral. If the number p that we want to check is not in the domain, the result of the integral is zero and the number is a prime. If instead, the result is an integer, this integer will tell us how many permutations of two divisors the number p has. And, in consequence information how many factors, the number p has. so, for any number p lower than 2m?- 1, you can check if it is prime or not, just making the numerical definite integration. We will apply this integral in a computer program to check the efficiency of the operation. We will check, if no further developments are done, the numerical integration is inefficient computing-wise compared with brute-force checking. To be added, is the question regarding the level of accuracy needed (number of decimals and number of steps in the numerical integration) to have a r

关键词： Primality Test Number Theory Primes Factorization Fourier Transform Parseval’s Theorem Time Domain Frequency Domain Numerical Computation

Complex patterns of environmental niche evolution in Iberian columbines (genus Aquilegia, ranunculaceae)

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Journal of Plant Ecology 2015年第5期8卷 457-467页

作者： Rafael Jaime Julio M.Alcántara jesús M.Bastida Pedro J.Rey Departamento de Biología Animal Biología Vegetal y EcologíaUniversidad de JaénCampus Las Lagunillass/n.Jaén E-23071Spain

Aims This study explores the patterns of niche differentiation in a group of seven closely related columbines(genus Aquilegia,ranunculaceae)from the Iberian *** of these columbines are subject to complex patterns of divergent selection across environ-ments,which partly explain the taxonomic structure of the *** suggests the hypothesis that niche divergence must have occurred along the process of diversification of the *** We used maxEnt to build environmental niche models of seven subspecies belonging to the three species of Aquilegia present in the Iberian *** these models,we compared the envi-ronmental niches through two different approaches:ENmtools and multivariate *** FindingsmaxEnt distributions conformed closely to the actual distribution of the study *** methods failed to uncover any clear patterns of niche differentiation or conservatism in Iberian *** analyses indicate the existence of dif-ferentiation along altitudinal gradients and along a gradient of climatic conditions determined by the summer precipitation and ***,climatic conditions related to winter tem-perature and precipitation,as well as soil properties,were equally likely to show conservatism or *** complex patterns of niche evolution we found suggest that Iberian Columbines have not been significantly constrained by forces of niche conservatism,so they could respond adaptively to the fast and profound climate changes in the Iberian Peninsula through the glacial cycles of the Pleistocene.

关键词： Aquilegia ecological niche modelling niche divergence niche conservatism evolution maxEnt ENmTools