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Loggerhead Sea Turtles Hand-Reared in Captivity: Isotopic Insights into Their Inherent Dietary Variation

Open Journal of Ecology 2024年第5期14卷 435-454页

作者： Brenda Natasha Mejía-Guarnizo Carlos Julio Polo-Silva Guiomar Aminta Jauregui-Romero antonio delgado-huertas Centro de Investigaciones en Ciencias Marinas (CICIMAR-IPN) La Paz M&#233xico Marine Biology Program Faculty of Natural Sciences and Engineering Jorge Tadeo Lozano University Santa Marta Colombia Sharky Management and Consulting Oldsmar FL USA Programa de Conservació n de Tortugas y Mam&#237feros Marinos (ProCTMM) Santa Marta Colombia Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR) Armilla Spain

Stable isotope analysis is a widely used method for gathering ecological insights into the diet and feeding habitats of various species. While captive studies often limit lethal sampling and differ from wild conditions, they offer valuable insights into inherent isotopic variations among individuals, which are often assumed to reflect differences between natural populations. In the Sea Turtle Conservation Program, loggerhead turtle hatchlings from different nests were fed. Necropsies were conducted on turtles that died during this period, obtaining bone fragments for analysis. We evaluated the isotopic variation of carbon (δ13C) and nitrogen (δ15N) in bone tissue across six turtle nests (n = 66 samples) and assessed differences in Straight Carapace Length (SCL, n = 71 samples). Using SIBER and nicheROVER in R, we calculated niche width and overlap, while the simmr package determined primary prey assimilation. Despite feeding the hatchlings the same prey, we observed variations in nitrogen isotope assimilation between nests. Nests 4 and 6 had a niche width >1.8‰, indicating consistent consumption frequencies across all prey and >70% niche overlap with other nests. In contrast, nests 1 and 2 showed a narrower niche width (Mugil sp. constituted the primary diet component (>40%) across all groups. This study demonstrates how factors like competition or prey preference can influence the assimilation of diet, even when the source remains constant (inherent variation).

关键词： Stable Isotopes Caretta caretta Head-Starting Nests Straight Carapace Length

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Megacryometeors:Distribution on Earth and Current Research

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AMBIO－人类环境杂志 2006年第6期35卷 314-316页

作者： Jesus Martinez-Frias antonio delgado huertas Planetary Geology Laboratory Centro de Astrobiologia Ctra de Ajalvirkm.4 28850 Torrejón de Ardoz MadridSpain Department of Earth Sciences and Environmental Chemistry Estación Experimental del Zaidín CSIC Prof.Albareda 1 18008 GranadaSpain

研究有关陨冰（ice falls）的历史记录，我们可以发现许多非常类似的事例。实际上，还没有任何关于晴天坠落的冰的适当研究，这些现象往往未经证实就被简单地归为飞机在高空的结冰现象、飞机卫生间产生的污水（蓝冰）或飞机水箱漏水而... 详细信息

研究有关陨冰（ice falls）的历史记录，我们可以发现许多非常类似的事例。实际上，还没有任何关于晴天坠落的冰的适当研究，这些现象往往未经证实就被简单地归为飞机在高空的结冰现象、飞机卫生间产生的污水（蓝冰）或飞机水箱漏水而结成的冰。然而，有必要重新考虑以下两个问题：首先，记载这些事件的历史文献可以追溯到19世纪上半叶，在飞机发明之前已经有了大量的记载。其次，如果在科学数据库（Webof Science，GeoRef）中，仔细检索众所周知的飞机结冰过程的有关案例，所得到的结论相悖于前文中简单的解释——在飞机任何部位都无法形成长达1m、重达几百公斤的冰。

关键词：陨冰地球结冰过程科学数据库历史记录历史文献飞机卫生间

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The Tianjin geothermal field (northeastern China): Geochemistry and implications for possible plugging phenomena

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Chinese Journal Of Geochemistry 2006年第B8期25卷 148-148页

作者： Angelo Minissale Daniele Borrini Giordano Montegrossi Franco Tassi Orlando Vaselli antonio delgado huertas Wanqing CHENG Jincheng YANG Xuzhou CHENG CNR-Institute of Geosciences and Earth Resources Via G La Pira 4-50121 Florence Italy Department of Earth Sciences Via G La Pira 4-50121 Florence ltaly Estaciōn Experimental del Zaidin （CSIC） Prof. Albareda 1 18008 Granada Spain Tianjin Aode Renewable Energy Research Institute Tianjin 300381 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

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Effect of Zn binding to phytate and humic substances on its uptake by wheat(Triticum durum L.)as affected by carbonates and Fe oxides

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Pedosphere 2022年第6期32卷 823-832页

作者： Ana M.GARCÍA-LÓPEZ Ramiro RECENA antonio delgado Department of Agronomy ETSIAUniversity of SevilleSeville 41013(Spain)

Although complexation with soil organic matter may improve zinc(Zn)bioavailability to plants,the effect of Zn sorbent surface on the use of complexed Zn by plants remains *** objective of this research was to elucidate how Zn complexation with humic substances(HS)and phytate affects the uptake of Zn by wheat plants depending on the main sorbent surface in growth media,i.e.,carbonates and Fe *** this end,two pot experiments were performed,one using Fe oxide-coated siliceous as the siliceous growth medium sand and the other using a mixture of calcareous sand and siliceous sand as the calcareous growth *** experiment involved three Zn sources,Zn-HS complex,Zn phytate,and ZnSO_(4).All sources were applied with surface irrigation at two Zn rates(0.25 and 2 mg kg^(-1) growth medium).The Zn-HS complex significantly increased Zn uptake by plants in both media,relative to the other two Zn sources,but no significant difference was observed between Zn phytate and ZnSO_(4).In the calcareous medium,Zn-HS complex and Zn phytate resulted in significantly higher dry biomass yields of wheat than ZnSO_(4).In the siliceous medium,spike and shoot dry biomass yields with Zn-HS complex at the low rate and Zn phytate at both rates were not significantly different from those with ZnSO_(4) at the high *** harvest,approximately 50%of the Zn applied as Zn-HS complex remained extractable by diethylenetriaminepentaacetic acid(DTPA),while this proportion was less than 20%for the other Zn ***,Zn-HS complex and Zn phytate are sources of available Zn for plants,and they are more effective than ZnSO_(4) in increasing plant growth,particularly when carbonates are the main Zn sorbent surface.

关键词： calcareous growth medium micronutrient organic matter organic phosphorus Zn availability Zn deficiency Zn sorbent surface Zn source

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Abiotic and biotic drivers of struvite solubilization in contrasting soils

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Pedosphere 2023年第6期33卷 828-837页

作者： antonio RUIZ-NAVARRO Manuel delgado-BAQUERIZO Concha CANO-DíAZ Carlos GARCíA Felipe BASTIDA Centro de Edafologia y Biologia Aplicada del Segura Consejo Superior de Investigaciones Cientificas(CEBAS-CSIC)Department of Soil and Water ConservationEspinardoMurcia E-30100Spain ICL Specialty Fertilizers Iberia TotanaMurcia E-30850Spain Laboratorio de Biodiversidad y Funcionamiento Ecosistemico Instituto de Recursos Naturales y Agrobiologia de Sevilla(IRNAS)CSICAv.Reina Mercedes 10Sevilla E-41012Spain IRNAS-CSIC Unidad Asociada Universidad Pablo de OlavideUniversidad Pablo de Olavide(UPO)Sevilla 41013Spain Centre for Research and Development in Agrifood Systems and Sustainability(CISAS) Instituto Politecnico de Viana do Castelo(IPVC)Rua Escola Industrial e Comercial Nun'Alvares 34Viana do Castelo 4900-347Portugal

Phosphorus(P) limitation in the coming decades calls for the utilization of alternative fertilizers in agriculture. Struvite is a promising P source, but its potential role as a fertilizer is dependent on different physical, chemical, and biological properties, which are very heterogeneous in soil, complicating the prediction of the best soil conditions for its application. Here, we evaluated the solubility of struvite in soil, its redistribution into P fractions, and its potential abiotic and biotic drivers in 62 globally distributed soils with contrasting properties through an incubation assay. We found that after 40 d, about 35% of struvite P was redistributed into soil fractions more accessible to plants and microbes. Phosphorus redistribution from struvite was driven by a complex suite of soil physical, chemical, and microbial properties as well as environmental factors that varied across soils. Soil texture played a critical role in determining the redistribution of P in struvite-amended soils in soluble(H2O extraction), labile(NaHCO3 extraction), and moderately labile(NaOH extraction) *** addition, the soil solution cation concentration was one of the most important drivers of available struvite-derived P fractions. The great importance of texture and cations in determining struvite-derived P fractions in soil was contrasted with the relatively minor role of pH. At the microbial level, the number of bacterial operational taxonomic units(OTUs) from the unfertilized soils that correlated with struvite-derived P fractions was higher than that of fungi. The number of OTUs that correlated with the struvite-derived soluble P fraction was dominated by fungi, whereas the number of OTUs that correlated with the struvite-derived labile P fraction was dominated by bacteria. Overall, this study provided a predictive framework for the potential use of struvite as a P fertilizer in contrasting soils.

关键词： bacteria fungi environmental factor operational taxonomic unit phosphorus fertilizer phosphorus fraction phosphorus solubilization soil fertility soil property

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Simulation of Fluid Flow in a Channel Induced by Three Types of Fin-Like Motion

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Journal of Bionic Engineering 2007年第3期4卷 165-176页

作者： Wojciech Kowalczyk antonio delgado Institute of Fluid Mechanics University of Erlangen-NurembergCauerstr. 4D-91058 ErlangenGermany

One of many interesting research activities in biofluidmechanics is dedicated to investigations of locomotion in water. Some of propulsion mechanisms observed in the underwater world are used in the development process of underwater autonomic vehicles （AUV）. In order to characterise several solutions according to their manoeuvrability, influence on the surrounding fluid and energetic efficiency, a detailed analysis of fin-like movement is indispensable. In the current paper an analysis of undulatory, oscillatory and combined fin-like movements by means of numerical simulation is carried out. The conservation equation of mass and the conservation equation of momentum axe solved with the Finite Volume Method （FWM） by use of the software CFX-10.0. The undulatory and oscillatory fin movements axe modelled with an equation that is implemented within an additional subroutine and joined with the main solver. N carried out in the computational domain, in which one fin is fixed in a flow-through water duct. Simulations axe carded out in the range of the Re number up to 105. The results show significant influence of applied fin motion on the velocity distribution in the surrounding fluid.

关键词： biofluid dynamics fro-like movement fish propulsion computational fluid dynamics

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Pacman Renormalization in Siegel Parameters of Bounded Type

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Advances in Pure Mathematics 2023年第10期13卷 674-693页

作者： Carlos antonio Marin-Mendoza Rogelio Valdez-delgado Centro de Investigación en Ciencias Instituto de Investigación en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos Cuernavaca Mexico

A novel method of renormalization called Pacman renormalization allows us to study (unicritical) Siegel functions through Pacman-type functions. It has been used to investigate the Siegel parameters with combinatorially periodic rotation number in the main cardioid of the Mandelbrot set. It is already known that it can be defined a Pacman renormalization operator such that for Siegel pacmen, with combinatorially periodic rotation numbers, the operator is compact, analytic and has a unique fixed point, at which it is hyperbolic with one-dimensional unstable manifold. In this paper we observe that this Pacman renormalization operator is compact and analytic at any Siegel Pacman or Siegel map with combinatorially bounded rotation number. This allows us to define a renormalization operator on the hybrid classes of the standard Siegel pacmen to which we built its horseshoe where the operator is topologically semiconjugated to the left shift on the space of bi-infinite sequences of natural numbers bounded by some constant.

关键词： Siegel Parameters Pacman Renormalization Bounded Type Continued Fraction

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Tax avoidance and earnings management:a neural network approach for the largest European economies

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Financial Innovation 2023年第1期9卷 558-582页

作者： Francisco J.delgado Elena Fernández‑Rodríguez Roberto García‑Fernández Manuel Landajo antonio Martínez‑Arias Department of Economics Faculty of Economics and BusinessUniversity of OviedoAvda.del CristoS/N33071 OviedoSpain Department of Accounting Faculty of Economics and BusinessUniversity of OviedoAvda.del CristoS/N33071 OviedoSpain Department of Applied Economics Faculty of Economics and BusinessUniversity of OviedoAvda.del CristoS/N33071 OviedoSpain

In this study,we investigate the relationship between tax avoidance and earnings management in the largest five European Union economies by using artificial neural network *** methodology allows us to deal with nonlinearities detected in the data,which is the principal contribution to the previous *** ana-lyzed Compustat data for Germany,the United Kingdom,France,Italy,and Spain for the 2006–2015 period,focusing on discretionary *** considered three tax avoidance measures,two based on the effective tax rate(ETR)and one on book-tax differences(BTD).Our results indicate the presence of nonlinear patterns and a posi-tive,statistically significant relationship between discretionary accruals and both ETR indicators implying that when companies resort to earnings management,a larger tax-able income—and thus higher ETR and lesser tax avoidance–would ***,as also highlighted by the fact that discretionary accruals do not appear to affect BTD,our evidence does not suggest that companies are exploiting tax manipulation to reduce their tax payments;thus,the gap between accounting and taxation seems largely unaf-fected by earnings management.

关键词： Tax avoidance Earnings management Artificial neural networks European Union

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A charged star with geometric Karmarkar condition

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Communications in Theoretical Physics 2023年第8期75卷 139-149页

作者： Gabino Estevez-delgado Joaquin Estevez-delgado Rafael Soto-Espitia antonio Rendón Romero Jorge Mauricio Paulin-Fuentes Facultad de Químico Farmacobiología de la Universidad Michoacana de San Nicolás de Hidalgo Facultad de Ciencias Físico Matemáticas de la Universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad Universitaria Facultad de Ingeniería Civil de la Universidad Michoacana de San Nicolás de Hidalgo Edificio A Ciudad Universitaria Facultad de Ingeniería Mecánica de la Universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad Universitaria División Académica de Ciencias Básicas de la Universidad Juárez Autónoma de Tabasco

In this paper,we analyse an analytical solution of the Einstein–Maxwell field equations that considers matter with anisotropic pressures in a static and spherically symmetric *** report the manner in which we obtained the solution,which is by means of the Karmarkar *** the model,we assume a state equation that describes the interaction of matter from quarks P=(c^(2)ρ-4B_(g))/3 and we consider the presence of electric charge,which can generate that the radial and tangential pressures are not *** a graphic manner,we analyse the physical properties of the model,taking as the observational data those of mass 1M⊙and radius7.69 km which were reported for the star Her *** charge values are found between 5.57×10^(18)C≤Q≤1.31×10^(20)C and the interval of the Bag constant Bg∈[118.7,122.13]MeV/fm^(3).Also,we show the stability of the configuration by means of the static stability criteria of Harrison–Zeldovich–Novikov((?M)/?ρc>0),as well as in regards to infinitesimal radial adiabatic perturbation,since the adiabatic indexγ>3.3 which guarantees the stability of the solution.

关键词： general relativity exact solutions anisotropic fluid Karmarkar condition

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On the Structure of Graded Leibniz Algebras

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Algebra Colloquium 2015年第1期22卷 83-96页

作者： antonio J. Calderon Martin Jose M. Sfinchez delgado Departamento de Matemdticas Universidad de Cadiz 11510 Puerto Real Cadiz Spain

We study the structure of graded Leibniz algebras with arbitrary dimension and over an arbitrary base field K. We show that any of such algebras ￡ with a symmetric G-support is of the form ￡ = U-∑jIj with U a subspace of ￡1, the homogeneous component associated to the unit element 1 in G, and any Ij a well described graded ideal of ￡, satisfying [Ij, Ik]= 0 if j≠ k. In the case of ￡ being of maximal length, we characterize the gr-simplicity of the algebra in terms of connections in the support of the grading.

关键词： graded Leibniz algebra infinite dimensional Leibniz algebra structure theory

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