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Avian Research 2022年第3期13卷 332-340页

作者： Rodrigo medel Manuel López-Aliste Francisco E.Fontúrbel Departamento de Ciencias Ecol ogicas Facultad de CienciasUniversidad de ChileSantiagoChile Instituto de Biología Facultad de CienciasPontificia Universidad Cat olica de ValparaísoValparaísoChile Millennium Nucleus of Patagonian Limit of Life(LiLi) ValdiviaChile

Hummingbird species have closely evolved with the plants they feed on,which is confirmed by their often tight ecological relationships in natural ***-plant interactions are of interest for research areas such as ecology,evolution,and even agriculture,as they usually inform on the conservation status of interacting species assemblages,and its disappearance may precede the population extinction of the species involved in the *** Chile,there are nine hummingbird species,which interact with a large and diverse number of angiosperm species in forest,desert,and mountain range *** motivation to perform this review is to systematize the available information regarding the flowering plants visited by hummingbird species in Chile,to present some basic plant-hummingbird pollination network metrics,and on this basis to identify the components of the plant-hummingbird relationships in need of further research.A plant-hummingbird metanetwork revealed a low connectance value,low niche overlap,and strong modularity among ***,the fact that most species present a strong allopatric distribution across Chile,suggests that network structure results mostly from the history of colonization rather than from ecological ***,the main threats to Chilean hummingbirds are anthropogenic disturbance and climate change,which disrupt hummingbird-plant interactions,leading to unpredictable ecological consequences at the community *** periods of drought may reduce the resource base for hummingbirds,with dramatic consequences for the maintenance of bird and plant populations.

关键词： Conservation Endemic species Habitat disturbance Pollination Trochilidae

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应用于固体样品直接分析的射频辉光光谱中等离子体空间解析的初步研究

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冶金分析 2009年第8期29卷 1-6页

作者： PISONERO J VALLEDOR R NELIS Th BORDEL N medel a.sanz 奥维耶多大学物理系法国科学研究中心奥维耶多大学物理分析化学系

设计了一种新的实验设备用于研究发射光谱的射频辉光中原子和离子的空间分布。通过测量沿等离子体羽流的不同原子和离子的发射强度来研究发生在等离子体内部的激发/离子化过程。该报导对辉光源与质谱联用的优化有较大意义,如离子提取的... 详细信息

设计了一种新的实验设备用于研究发射光谱的射频辉光中原子和离子的空间分布。通过测量沿等离子体羽流的不同原子和离子的发射强度来研究发生在等离子体内部的激发/离子化过程。该报导对辉光源与质谱联用的优化有较大意义,如离子提取的最佳位置。初步研究了连续和脉冲射频辉光光谱中等离子体的空间解析,尤其对影响发射信号的输入功率、压强及占空比等参数进行了评价。

关键词：射频辉光发射光谱空间解析

Quantitative Elemental Speciation :Challenges and Strategies Basedon Multi-Labelled Multi-Species Isotope Dilution ICP-MS

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光谱学与光谱分析 2004年第2期24卷 255-255页

作者： Alfredo sanz-medel Pablo RODR■GUEZ-GONZLEZ Jorge RUIZ ENCINAR J .Ignacio GARC■A ALONSO Department of Physical and Analytical Chemistry Faculty of Chemistry Juliun Clavena833006Oviedo Spain.Department of Physical and Analytical Chemistry Faculty of Chemistry Juliun Clavena833006Oviedo Spain.Department of Physical and Analytical Chemistry Faculty of Chemistry Juliun Clavena833006Oviedo Spain.Department of Physical and Analytical Chemistry Faculty of Chemistry Juliun Clavena833006Oviedo Spain.

According to IUPAC, a chemical species is defined as "the specific form of an element defined as to isotope composition, electronic oxidation state and/or complex or molecular structure . To carry out chemical speciation, new speciation analysis techniques and strategies are needed. Probably the most popular and useful techniques for speciation analysis are hybrid techniques where a powerful separation is coupled (preferable "on-line") to an element-specific detector. In fact, the whole strategy for speciation analysis involves a considerable number of discrete steps. These include usually: solid-liquid extraction (if the sample is solid), preconcentration, derivatization, separation of derivatized analytes (e.g. chromatography) and final specific detection (e. g. "on-line" ICP-MS). It is well known that important errors can occur at any of those individual speciation steps. First, solid-liquid extractions should preserve the molecular form (species) of the analytes. Second, preconcentration, derivatization, separation and detection speciation methods should be fully investigated and understood in order to obtain accurate (reliable) determinations of the sought *** all the above, it is clear that validation of quantitative speciation results is urgently needed. A powerful approach for analytical validation is the use of isotope dilution analysis (IDA). Therefore the application of "speciated" IDA (SIDA) techniques for validation of results for mono-, di-, and tributyltin (MBT, DBT and TBT, respectively) in sediments and seawater samples~[3] will be discussed using a multi-species spike enriched with ~(119)Sn and final measurement by a hybrid GC-ICP-MS technique. Similarly, the synthesis of multi-labelled multi-species spikes will be described. The application of "doubly- and triply-labelled spikes" has allowed the evaluation of the extent of possible decomposition reactions (the corresponding decomposition factors can be quantified) during several solid-liq

关键词：电感耦合等离子发射光谱 ICP-MS 物种形成物质组成同位素示踪定量分析

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射频辉光放电飞行时间质谱法分析薄膜:脉冲模式与连续模式的比较

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冶金分析 2009年第11期29卷 1-7页

作者： BORDEL N LOBO L PISONERO J PEREIRO R TUCCITTO N LICCIARDELLO A TEMPEZ A CHAPON P HOHL M MICHLER J sanz-medel A 奥维多大学科学学院物理系奥维多大学化学学院物理和分析化学系卡塔尼亚大学化学系 Horiba Jobin Yvon公司 Tofwerk AG公司 EMPA材料科技有限公司

高级多层材料的直接表面和深度分布化学分析要求了解多维信息,包括同时了解元素和分子信息。用飞行时间质谱法(TOFMS)检测的脉冲式射频辉光放电(pulsed rf-GDs)可以从种类繁多的材料中直接提供化学信息,且简单快捷。另一方面,脉冲式射... 详细信息

高级多层材料的直接表面和深度分布化学分析要求了解多维信息,包括同时了解元素和分子信息。用飞行时间质谱法(TOFMS)检测的脉冲式射频辉光放电(pulsed rf-GDs)可以从种类繁多的材料中直接提供化学信息,且简单快捷。另一方面,脉冲式射频辉光放电中输入功率的时间分布由于不同的离子化机理产生3个主要放电阶段(峰前,高峰平稳,峰后)。结果证明将辉光放电离子源和一个快速飞行时间质谱仪相结合能够实现在不同的脉冲阶段几乎同时获得元素和分子信息。

关键词：射频辉光放电飞行时间质谱法薄膜脉冲模式连续模式

Inflammation and intracranial aneurysms:mechanisms of initiation,growth,and rupture

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Neuroimmunology and Neuroinflammation 2015年第1期2卷 68-76页

作者： Peter S.Amenta Edison Valle Aaron S.Dumont Ricky medel Department of Neurosurgery Tulane University School of MedicineNew OrleansLA 70112USA

Outcomes following aneurysmal subarachnoid hemorrhage remain poor in many patients,despite advances in microsurgical and endovascular ***,considerable effort has been placed in determining the mechanisms of aneurysm formation,growth,and *** environmental and genetic factors are implicated as key components in the aneurysm ***,sufficient evidence exists to incriminate the inflammatory response as the common pathway leading to aneurysm generation and *** to this model is the interaction between the vessel wall and inflammatory *** of the endothelium and vascular smooth muscle cells(VSMCs)promotes a chronic pathological inflammatory response that progressively weakens the vessel *** review the literature pertaining to the cellular and chemical mechanisms of inflammation that contribute to aneurysm *** stress and alterations in blood flow are discussed regarding their role in promoting chronic *** cell and VSMC dysfunction are examined concerning vascular *** contribution of inflammatory cytokines,especially tumor necrosis factor‑α is *** cell infiltration,particularly macrophage‑mediated deterioration of vascular integrity,is *** discuss the inflammation as a means to determine aneurysms at greatest risk of ***,future therapeutic implications of pharmacologic modulation of the inflammation are discussed.

关键词： Aneurysm endothelium inflammation subarachnoid hemorrhage vascular smooth muscle cells

The role of leukocytes in the formation and rupture of intracranial aneurysms

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Neuroimmunology and Neuroinflammation 2015年第1期2卷 107-114页

作者： Michael J.Strong Peter S.Amenta Aaron S.Dumont Ricky medel Department of Neurosurgery Tulane University School of MedicineNew OrleansLA 70112USA

Ruptured intracranial aneurysms(IAs)affect a small proportion of the population;however,the morbidity and mortality is disproportionally *** little is known about IA formation,progression,and rupture,mounting evidence suggests that inflammation may play an important role in IA *** is emerging evidence to suggest that leukocytes play a key role in generating and maintaining a pathologic inflammatory response that leads to aneurysm formation and *** present the current literature pertaining to the role of leukocytes in aneurysm formation,progression,and *** contributions of individual cell types are detailed,with special attention paid to the cytokine and molecular *** role of magnetic resonance imaging as a means by which to evaluate aneurysm‑associated inflammation is ***,we discuss leukocytes as potential targets of pharmacologic intervention.

关键词： Aneurysm inflammation inflammatory cells leukocytes lymphocytes macrophages mast cells neutrophils

Stability Conditions of Fuzzy Filter Type III

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Journal of Signal and Information Processing 2011年第3期2卷 245-251页

作者： José de Jesús medel Juárez Juan Carlos García Infante Juan Carlos Sánchez García 不详

A digital fuzzy logic filter of type III interacts with a real model signal reference to obtain the best answer in the sense of minimum mean square error of the output. The key part of the filter is a fuzzy mechanism that adaptively selects and emits answer according to the changes of the external reference signal. Based on input signal level, this fuzzy filter selects the best parameter values from a set of membership in the knowledge base (KB), and the filter weights are updated according to the reference signal in a natural form. With this fuzzy structure the filter reduces error. The simulation result shows the stability of the filter. The states of the filtering process require that all of its answers are bounded by the error criteria probabilistically.

关键词： Digital Filtering Fuzzy Systems Estimation Stability

Evolutive Neural Net Fuzzy Filtering: Basic Description

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Journal of Intelligent Learning Systems and Applications 2010年第1期2卷 12-18页

作者： Juan C. García Infante J. Jesús medel Juárez Juan C. Sánchez García 不详

The paper describes the operation principles of the evolutive neuro fuzzy filtering (ENFF) properties, which based on back propagation fuzzy neural net, this filter adaptively choose and emit a decision according with the reference signal changes of an external reference process, in order to actualize the best correct new conditions updating a process. This neural net fuzzy filter mechanism selects the best parameter values into the knowledge base (KB), to update the filter weights giving a good enough answers in accordance with the reference signal in natural sense. The filter architecture includes a decision making stage using an inference into its structure to deduce the filter decisions in accordance with the previous and actual filter answer in order to updates the new decision with respect to the new reference system con-ditions. The filtering process states require that bound into its own time limit as real time system, considering the Ny-quist and Shannon criteria. The characterization of the membership functions builds the knowledge base in probabilis-tic sense with respect to the rules set inference to describe the reference system and deduce the new filter decision, per-forming the ENFF answers. Moreover, the paper describes schematically the neural net architecture and the deci-sion-making stages in order to integrate them into the filter architecture as intelligent system. The results expressed in formal sense use the concepts into the paper references with a simulation of the ENFF into a Kalman filter structure using the Matlab? tool.

关键词： Digital Filters Neuro Fuzzy Systems Evolutive Systems Real Time

Fuzzy Digital Filtering: Signal Interpretation

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International Journal of Communications, Network and System Sciences 2011年第5期4卷 297-303页

作者： Juan C. García Infante J. Jesús medel Juárez Juan C. Sánchez García 不详

The paper makes a description of the fuzzy filter properties considering its operational principles. A digital filter interacts with a reference model signal into real process in order to get the best corresponding answer, having the minimum error at the filter output using the mean square criterion. Adding into this filter structure a fuzzy mechanism, to obtain an intelligent filtering because adaptively select and emit a decision answer according with the external reference signal changes, in order to actualize the best correct new conditions updating a process dynamically. The interpretation of the input signal level describes the operation of the reference model, to update the filter weights giving the answers approximation in accordance with the reference signal in natural form. Finally the paper shows the simulations results of the fuzzy filter into the Kalman structure using the Matlab? tool.

关键词： Digital Filters Fuzzy Systems Signal Processing Estimation Probability