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Crescimento, esporulação e virulência do inóculo de Cercospora piaropi, agente de biocontrole do aguapé

Ávila, Zilá R. de; Pitelli, Robinson A.
Fonte: Sociedade Brasileira de Fitopatologia Publicador: Sociedade Brasileira de Fitopatologia
Tipo: Artigo de Revista Científica Formato: 189-192
Português
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O presente ensaio foi realizado com o objetivo de avaliar a produção de biomassa micelial bem como a esporulação de Cercospora piaropi, nos meios líquidos V8, ETD (Extrato de Tomate Diluído) e BD (Batata - Dextrose), em períodos de cultivo de 96, 120, 144 e 168 h, sob agitação constante. Adicionalmente foi avaliado o efeito de períodos de desidratação da biomassa micelial (24, 48, 72, 96 e 120 h) sobre a esporulação. Os inóculos obtidos foram avaliados quanto à severidade da doença em plantas de aguapé (Eichhornia crassipes). de acordo com os resultados, o meio ETD proporcionou maior crescimento micelial em relação aos meios BD e V8, destacando-se o período de 144 h de agitação. Entretanto, o meio V8 induziu esporulação superior do patógeno, quando cultivado por 120 h. Os inóculos obtidos nos meios V8 e ETD causaram maiores valores de severidade da doença. O período de desidratação da biomassa micelial a partir de 72 h favoreceu maior produção de conídios. Não houve efeito do período de desidratação sobre a severidade da doença.; The current assay was carried out to evaluate the mycelial biomass production and sporulation of Cercospora piaropi in V8, ETD and BD liquid media at incubation periods of 96...

Coupling Between Mitochondrial Mutation and Energy Transduction*

Mahler, Henry R.; Bastos, Roberto N.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1974 Português
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Upon incubation with ethidium bromide (Etd Br) isolated mitochondria of Saccharomyces cerevisiae have been shown to be capable of performing five novel reactions: (a) a single scission of their DNA (mtDNA) coincident with (b) the incorporation of Etd Br into the product (mtDNA → 2 mtDNA′-Etd Br); (c) an energy- (and probably ATP-) requiring degradation of mtDNA′-Etd Br to acid-labile products. These reactions acting in series generate (d) a DNase dependent on both Etd Br and an energy supply with mtDNA′-Etd Br as an obligatory intermediate. Coincident with (d) there occurs (e) an activation of adenosinetriphosphatase. Experiments with specific inhibitors suggest that the enzyme responsible is the mitochondrial adenosinetriphosphatase complex itself, and that it and the ability to carry out reactions (a) through (e) are tightly coupled to the energy-transducing functions of the particle.

Electron-Transfer Ion/Ion Reactions of Doubly Protonated Peptides: Effect of Elevated Bath Gas Temperature

Pitteri, Sharon J.; Chrisman, Paul A.; McLuckey, Scott A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/09/2005 Português
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In this study, the electron-transfer dissociation (ETD) behavior of cations derived from 27 different peptides (22 of which are tryptic peptides) has been studied in a 3D quadrupole ion trap mass spectrometer. Ion/ion reactions between peptide cations and nitrobenzene anions have been examined at both room temperature and in an elevated temperature bath gas environment to form ETD product ions. From the peptides studied, the ETD sequence coverage tends to be inversely related to peptide size. At room temperature, very high sequence coverage (~100%) was observed for small peptides (≤7 amino acids). For medium-sized peptides composed of 8–11 amino acids, the average sequence coverage was 46%. Larger peptides with 14 or more amino acids yielded an average sequence coverage of 23%. Elevated-temperature ETD provided increased sequence coverage over room-temperature experiments for the peptides of greater than 7 residues, giving an average of 67% for medium-sized peptides and 63% for larger peptides. Percent ETD, a measure of the extent of electron transfer, has also been calculated for the peptides and also shows an inverse relation with peptide size. Bath gas temperature does not have a consistent effect on percent ETD, however. For the tryptic peptides...

Global proteomic profiling of phosphopeptides using electron transfer dissociation tandem mass spectrometry

Molina, Henrik; Horn, David M.; Tang, Ning; Mathivanan, Suresh; Pandey, Akhilesh
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
Português
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Electron transfer dissociation (ETD) is a recently introduced mass spectrometric technique that provides a more comprehensive coverage of peptide sequences and posttranslational modifications. Here, we evaluated the use of ETD for a global phosphoproteome analysis. In all, we identified a total of 1,435 phosphorylation sites from human embryonic kidney 293T cells, of which 1,141 (≈80%) were not previously described. A detailed comparison of ETD and collision-induced dissociation (CID) modes showed that ETD identified 60% more phosphopeptides than CID, with an average of 40% more fragment ions that facilitated localization of phosphorylation sites. Although our data indicate that ETD is superior to CID for phosphorylation analysis, the two methods can be effectively combined in alternating ETD and CID modes for a more comprehensive analysis. Combining ETD and CID, from this single study, we were able to identify 80% of the known phosphorylation sites in >1,000 phosphorylated peptides analyzed. A hierarchical clustering of the identified phosphorylation sites allowed us to discover 15 phosphorylation motifs that have not been reported previously. Overall, ETD is an excellent method for localization of phosphorylation sites and should be an integral component of any strategy for comprehensive phosphorylation analysis.

Lead optimization of antifungal peptides with 3D NMR structures analysis

Landon, Céline; Barbault, Florent; Legrain, Michèle; Menin, Laure; Guenneugues, Marc; Schott, Valérie; Vovelle, Françoise; Dimarcq, Jean-Luc
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: Artigo de Revista Científica
Publicado em /03/2004 Português
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Antimicrobial peptides are key components of the innate immune response in most multicellular organisms. These molecules are considered as one of the most innovative class of anti-infective agents that have been discovered over the last two decades, and therefore, as a source of inspiration for novel drug design. Insect cystein-rich antimicrobial peptides with the CSαβ scaffold (an α-helix linked to a β-sheet by two disulfide bridges) represent particularly attractive templates for the development of systemic agents owing to their remarkable resistance to protease degradation. We have selected heliomicin, a broad spectrum antifungal CSαβ peptide from Lepidoptera as the starting point of a lead optimization program based on phylogenic exploration and fine tuned mutagenesis. We report here the characterization, biological activity, and 3D structure of heliomicin improved analogs, namely the peptides ARD1, ETD-135, and ETD-151. The ARD1 peptide was initially purified from the immune hemolymph of the caterpillars of Archeoprepona demophoon. Although it differs from heliomicin by only two residues, it was found to be more active against the human pathogens Aspergillus fumigatus and Candida albicans. The peptides ETD-135 and ETD-151 were engineered by site-directed mutagenesis of ARD1 in either cationic or hydrophobic regions. ETD-135 and ETD-151 demonstrated an improved antifungal activity over the native peptides...

A supplemental activation method for high efficiency electron transfer dissociation of doubly protonated peptide precursors

Swaney, Danielle L.; McAlister, Graeme C.; Wirtala, Matthew; Schwartz, Jae C.; Syka, John E.P.; Coon, Joshua J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/01/2007 Português
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Electron transfer dissociation (ETD) delivers the unique attributes of electron capture dissociation (ECD) to mass spectrometers that utilize radio frequency (RF) trapping-type devices (e.g., quadrupole ion traps). The method has generated significant interest because of its compatibility with chromatography and its ability to: (1) preserve traditionally labile post-translational modifications (PTMs) and (2) randomly cleave the backbone bonds of highly charged peptide and protein precursor ions. ETD, however, has shown limited applicability to doubly protonated peptide precursors, [M+2H]2+, the charge and type of peptide most frequently encountered in “bottom-up” proteomics. Here we describe a supplemental collisional-activation (CAD) method that targets the non-dissociated (intact) electron transfer (ET) product species ([M+2H]+•) to improve ETD efficiency for doubly protonated peptides (ETcaD). A systematic study of supplementary activation conditions revealed that low energy CAD of the ET product population leads to the near-exclusive generation of c and z-type fragment ions with relatively high efficiency (77 ± 8%). Compared to those formed directly via ETD, the fragment ions were found to comprise increased relative amounts of the odd-electron c-type ions (c+•) and the even-electron z-type ions (z+). A large-scale analysis of 755 doubly charged tryptic peptides was conducted to compare the method (ETcaD) to ion trap CAD and ETD. ETcaD produced a median sequence coverage of 89% – a significant improvement over ETD (63%) and ion trap CAD (77%).

Electron Transfer Dissociation of iTRAQ Labeled Peptide Ions

Han, Hongling; Pappin, Darryl J.; Ross, Philip L; McLuckey, Scott A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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Triply and doubly charged iTRAQ (isobaric tagging for relative and absolute quantitation) labeled peptide cations from a tryptic peptide mixture of bovine carbonic anhydrase II were subjected to electron transfer ion/ion reactions to investigate the effect of charge bearing modifications associated with iTRAQ on the fragmentation pattern. It was noted that electron transfer dissociation (ETD) of triply charged or activated ETD (ETD + supplemental collisional activation of intact electron transfer species) of doubly charged iTRAQ tagged peptide ions yielded extensive sequence information, in analogy with ETD of unmodified peptide ions. That is, addition of the fixed charge iTRAQ tag showed relatively little deleterious effect on the ETD performance of the modified peptides. ETD of the triply charged iTRAQ labeled peptide ions followed by collision-induced dissociation (CID) of the product ion at m/z 162 yielded the reporter ion at m/z 116, which is the reporter ion used for quantitation via CID of the same precursor ions. The reporter ion formed via the two-step activation process is expected to provide quantitative information similar to that directly produced from CID. A 103 Da neutral loss species observed in the ETD spectra of all the triply and doubly charged iTRAQ labeled peptide ions is unique to the 116 Da iTRAQ reagent...

Methods for analyzing peptides and proteins on a chromatographic timescale by electron-transfer dissociation mass spectrometry

Udeshi, Namrata D; Compton, Philip D; Shabanowitz, Jeffrey; Hunt, Donald F; Rose, Kristie L
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
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Advancement in proteomics research relies on the development of new, innovative tools for identifying and characterizing proteins. Here, we describe a protocol for analyzing peptides and proteins on a chromatographic timescale by coupling nanoflow reverse-phase (RP) liquid chromatography (LC) to electron-transfer dissociation (ETD) mass spectrometry. For this protocol, proteins can be proteolytically digested before ETD analysis, although digestion is not necessary for all applications. Proteins ≤30 kDa can be analyzed intact, particularly if the objective is protein identification. Peptides or proteins are loaded onto a RP column and are gradient-eluted into an ETD-enabled mass spectrometer. ETD tandem mass spectrometry (MS/MS) provides extensive sequence information required for the unambiguous identification of peptides and proteins and for characterization of posttranslational modifications. ETD is a powerful MS/MS technique and does not compromise the sensitivity and speed necessary for online chromatographic separations. The described procedure for sample preparation, column packing, sample loading and ETD analysis can be implemented in 5–15 h.

Trans-Proteomic Pipeline supports and improves analysis of electron transfer dissociation datasets

Deutsch, Eric W.; Shteynberg, David; Lam, Henry; Sun, Zhi; Eng, Jimmy K.; Carapito, Christine; von Haller, Priska D.; Tasman, Natalie; Mendoza, Luis; Farrah, Terry; Aebersold, Ruedi
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/2010 Português
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Electron transfer dissociation (ETD) is an alternative fragmentation technique to collision induced dissociation (CID) that has recently become commercially available. ETD has several advantages over CID. It is less prone to fragmenting amino acid side chains, especially those that are modified, thus yielding fragment ion spectra with more uniform peak intensities. Further, precursor ions of longer peptides and higher charge states can be fragmented and identified. However, analysis of ETD spectra has a few important differences that require the optimization of the software packages used for the analysis of CID data, or the development of specialized tools. We have adapted the Trans-Proteomic Pipeline (TPP) to process ETD data. Specifically, we have added support for fragment ion spectra from high charge precursors, compatibility with charge-state estimation algorithms, provisions for the use of the Lys-C protease, capabilities for ETD spectrum library building, and updates to the data formats to differentiate CID and ETD spectra. We show the results of processing datasets from several different types of ETD instruments and demonstrate that application of the ETD-enhanced TPP can increase the number of spectrum identifications at a fixed false discovery rate by as much as 100% over native output from a single sequence search engine.

Electron Transfer Reagent Anion Formation via Electrospray Ionization and Collision-induced Dissociation

Huang, Teng-Yi; Emory, Joshua F.; O’Hair, Richard A.J.; McLuckey, Scott A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/11/2006 Português
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A strategy is described and demonstrated for the formation of reagent anions via electrospray ionization (ESI) for electron transfer dissociation (ETD). To circumvent difficulties associated with formation of high mass-to-charge ratio (m/z) reagent anions, it is desirable to form ETD reagents via means other than those that require reagent molecule vaporization. ESI is a candidate method but anions that are generally generated efficiently by ESI tend to react with multiply protonated polypeptides via proton transfer. The strategy described herein involves the use of a precursor reagent molecule that ionizes efficiently via electrospray ionization and that can subsequently be converted to an ETD reagent via gas-phase dissociation. The approach is demonstrated with arene carboxylic acids that yield strong signals associated with the deprotonated molecule and that subsequently undergo collision-induced dissociation (CID) by loss of CO2. In the present work, triply protonated KGAILKGAILR served as a test substrate for the CID product ions to give rise to ETD. Several precursor molecules were shown to be capable of generating ETD reagents via ESI followed by CID. These included 9-anthracenecarboxylic acid, 2-fluoro-5-iodobenzoic acid, and 2-(fluoranthene-8-carbonyl)-benzoic acid. The latter molecule has the most attractive set of characteristics as a precursor for a relatively high m/z ratio ETD reagent.

Large-scale Identification of Endogenous Secretory Peptides Using Electron Transfer Dissociation Mass Spectrometry*

Sasaki, Kazuki; Osaki, Tsukasa; Minamino, Naoto
Fonte: The American Society for Biochemistry and Molecular Biology Publicador: The American Society for Biochemistry and Molecular Biology
Tipo: Artigo de Revista Científica
Português
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Mass spectrometry-based unbiased analysis of the full complement of secretory peptides is expected to facilitate the identification of unknown biologically active peptides. However, tandem MS sequencing of endogenous peptides in their native form has proven difficult because they show size heterogeneity and contain multiple internal basic residues, the characteristics not found in peptide fragments produced by in vitro digestion. Endogenous peptides remain largely unexplored by electron transfer dissociation (ETD), despite its widespread use in bottom-up proteomics. We used ETD, in comparison to collision induced dissociation (CID), to identify endogenous peptides derived from secretory granules of a human endocrine cell line. For mass accuracy, both MS and tandem MS were analyzed on an Orbitrap. CID and ETD, performed in different LC-MS runs, resulted in the identification of 795 and 569 unique peptides (ranging from 1000 to 15000 Da), respectively, with an overlap of 397. Peptides larger than 3000 Da accounted for 54% in CID and 46% in ETD identifications. Although numerically outperformed by CID, ETD provided more extensive fragmentation, leading to the identification of peptides that are not reached by CID. This advantage was demonstrated in identifying a new antimicrobial peptide from neurosecretory protein VGF (non-acronymic)...

Electron Transfer Dissociation of Milk Oligosaccharides

Han, Liang; Costello, Catherine E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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For structural identification of glycans, the classic collision-induced dissociation (CID) spectra are dominated by product ions that derived from glycosidic cleavages, which provide only sequence information. The peaks from cross-ring fragmentation are often absent or have very low abundances in such spectra. Electron transfer dissociation (ETD) is being applied to structural identification of carbohydrates for the first time, and results in some new and detailed information for glycan structural studies. A series of linear milk sugars was analyzed by a variety of fragmentation techniques such as MS/MS by CID and ETD, and MS3 by sequential CID/CID, CID/ETD, and ETD/CID. In CID spectra, the detected peaks were mainly generated via glycosidic cleavages. By comparison, ETD generated various types of abundant cross-ring cleavage ions. These complementary cross-ring cleavages clarified the different linkage types and branching patterns of the representative milk sugar samples. The utilization of different MS3 techniques made it possible to verify initial assignments and to detect the presence of multiple components in isobaric peaks. Fragment ion structures and pathways could be proposed to facilitate the interpretation of carbohydrate ETD spectra and the main mechanisms were investigated. ETD should contribute substantially to confident structural analysis of a wide variety of oligosaccharides.

Reversed phase-high performance liquid chromatographic method for simultaneous estimation of tolperisone hydrochloride and etodolac in a combined fixed dose oral formulations

Patel, Mit J.; Badmanaban, R.; Patel, C. N.
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
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A reversed-phase liquid chromatographic (RP-HPLC) method was developed for the simultaneous determination of tolperisone hydrochloride (TOLP) and etodolac (ETD) in a combined fixed dose oral formulation. The analysis was carried out using a phenomenax C-18, pre-packed column. A mobile phase containing a phosphate buffer (pH 5.5) : Methanol : Acetonitrile : Tri-ethylamine (40 : 40 : 20 : 1.5), with the pH adjusted to orthophosphoric acid, was pumped at a flow rate of 1.0 ml min1 with a UV-detector and PDA detection at 257 nm. Retention time was 3.91 minutes and 6.89 minutes for TOLP and ETD, respectively. The method was validated for linearity, accuracy, precision, sensitivity, and specificity. The method showed good linearity in the range of 3 – 21 μg ml for TOLP μg / ml and 8 – 56 μg / ml for ETD. The detection limit of the proposed method was 0.16 μg / ml and 0.58 μg / ml for TOLP and ETD, respectively. The quantification limit of the proposed method was 0.51 μg / ml and 1.7 μg / ml for TOLP and ETD, respectively. The % recovery was within the range of 99.42 – 101.15 for TOLP and 98.63 – 100.94 for ETD. The percentage RSD for precision of the method was found to be less than 2%. The method was validated as per the International Conference on Harmonization (ICH) guidelines. The developed method could be applied for routine analysis of TOLP and ETD in tablet dosage form.

EXPONENTIAL TIME DIFFERENCING FOR HODGKIN–HUXLEY-LIKE ODES

Börgers, Christoph; Nectow, Alexander R.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //2013 Português
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Several authors have proposed the use of exponential time differencing (ETD) for Hodgkin–Huxley-like partial and ordinary differential equations (PDEs and ODEs). For Hodgkin–Huxley-like PDEs, ETD is attractive because it can deal effectively with the stiffness issues that diffusion gives rise to. However, large neuronal networks are often simulated assuming “space-clamped” neurons, i.e., using the Hodgkin–Huxley ODEs, in which there are no diffusion terms. Our goal is to clarify whether ETD is a good idea even in that case. We present a numerical comparison of first- and second-order ETD with standard explicit time-stepping schemes (Euler’s method, the midpoint method, and the classical fourth-order Runge–Kutta method). We find that in the standard schemes, the stable computation of the very rapid rising phase of the action potential often forces time steps of a small fraction of a millisecond. This can result in an expensive calculation yielding greater overall accuracy than needed. Although it is tempting at first to try to address this issue with adaptive or fully implicit time-stepping, we argue that neither is effective here. The main advantage of ETD for Hodgkin–Huxley-like systems of ODEs is that it allows underresolution of the rising phase of the action potential without causing instability...

Exploring Salt Bridge Structures of Gas-Phase Protein Ions using Multiple Stages of Electron Transfer and Collision Induced Dissociation

Zhang, Zhe; Browne, Shaynah J.; Vachet, Richard W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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The gas-phase structures of protein ions have been studied by electron transfer dissociation (ETD) and collision-induced dissociation (CID) after electrospraying these proteins from native-like solutions into a quadrupole ion trap mass spectrometer. Because ETD can break covalent bonds while minimally disrupting non-covalent interactions, we have investigated the ability of this dissociation technique together with CID to probe the sites of electrostatic interactions in gas phase protein ions. By comparing spectra from ETD with spectra from ETD followed by CID, we find that several proteins, including ubiquitin, CRABP I, azurin, and β-2-microglobulin, appear to maintain many of the salt bridge contacts known to exist in solution. To support this conclusion, we also performed calculations to consider all possible salt bridge patterns for each protein, and we find that the native salt bridge pattern explains the experimental ETD data better than nearly all other possible salt bridge patterns. Overall, our data suggest that ETD and ETD/CID of native protein ions can provide some insight into approximate location of salt bridges in the gas phase.

Designing for Dual Submission of ETDs

Bolton, Philip, Jr
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
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The main objective is to get participants thinking about how they can solve problems associated with a dual submission of ETDs. Many institutions choose to archive ETDs in their repositories, but also mandate, insist, or permit ETDs to be submitted to ProQuest via the UMI ETD Administrator. The Administrator offers a no-submission-fee route for ETD inclusion in ProQuest’s ubiquitous subscription databases. At FIU, after deciding on a mandatory ETD Policy in July 2011, we considered moving from a payment/snail mail submission to altogether scrapping submission to ProQuest; however, our librarians made a case for keeping at least an option for ProQuest submission. After consideration of all the options, implementing the UMI ETD Administrator seemed the most logical because it relieves payment, paperwork, and snail mail. Unfortunately, the UMI ETD Administrator creates as many problems as it solves e.g., the dual submission. According to the Berkman Center’s Good Practices for University Open-Access Policies, the university should offer to make additional deposits outside of the institutional repository. Thus, we sought to find a way for the students to only submit once to our DigitalCommons Institutional Repository. By June 2012...

Designing for Dual Submission of ETDs

Bolton, Philip, Jr
Fonte: SelectedWorks Publicador: SelectedWorks
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.471458%
The main objective is to get participants thinking about how they can solve problems associated with a dual submission of ETDs. Many institutions choose to archive ETDs in their repositories, but also mandate, insist, or permit ETDs to be submitted to ProQuest via the UMI ETD Administrator. The Administrator offers a no-submission-fee route for ETD inclusion in ProQuest’s ubiquitous subscription databases. At FIU, after deciding on a mandatory ETD Policy in July 2011, we considered moving from a payment/snail mail submission to altogether scrapping submission to ProQuest; however, our librarians made a case for keeping at least an option for ProQuest submission. After consideration of all the options, implementing the UMI ETD Administrator seemed the most logical because it relieves payment, paperwork, and snail mail. Unfortunately, the UMI ETD Administrator creates as many problems as it solves e.g., the dual submission. According to the Berkman Center’s Good Practices for University Open-Access Policies, the university should offer to make additional deposits outside of the institutional repository. Thus, we sought to find a way for the students to only submit once to our DigitalCommons Institutional Repository. By June 2012...

Extralaryngeal Terminal Division of the Inferior Laryngeal Nerve: Anatomical Classification by a Surgical Point of View

Gurleyik, Emin
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
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Background. Complete anatomic knowledge including all variations of the inferior laryngeal nerve (ILN) is mandatory for thyroid surgeon. Extralaryngeal terminal division (ETD) of the ILN has significant importance for the safety of thyroidectomy. Material and Methods. Surgical dissection of 200 ILNs was performed on 100 cases. The presence of ETD of the nerve was determined intraoperatively. We propose by a surgical point of view a regional (segmental) classification of ETD of the ILN along its cervical course. Results. ETD has been observed in 54/200 nerves (27%). Great majority are bifurcated nerves (trifurcation 2%). Four types of ETD are classified. In type 1 (arterial; 46.3%), ETD has occurred near inferior thyroid artery (ITA). In type 2 (postarterial; 31.5%), division has been found on postarterial segment. In type 3 (prelaryngeal; 11%), division has been located very close to laryngeal entry point. In type 4 (prearterial; 11%), ETD has occurred before the nerve crossing the ITA. Conclusions. ETD of the ILN is a common anatomical variation. The bifurcation occurs in the ILN at various distances from laryngeal entry point. The classification increasing surgeons' awareness may help to simplify identification and exposure of terminal branches. Preservation of both extralaryngeal terminal branches of the ILN has paramount importance for the safety of thyroid operations.

Estimation of real evapotranspiration and its variation in Mediterranean landscapes of central-southern Chile

Mattar Bader, Cristián; Olivera Guerra, L.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo de revista
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Artículo de publicación ISI; Evapotranspiration (ETd) is a key controller in the ecohydrological processes of semi-arid landscapes. This is the case of the dry land in Chile’s central-southern zone, where forestry, farming and livestock activities must adapt to precipitation with considerable year-on-year variations. In this study, the spatial distribution of ETd was estimated in relation to the land use map and physical parameters of the soil. The ETd was estimated through the Simplified Surface Energy Balance Index (S-SEBI) using data from weather stations and remote data provided by the ASTER and MODIS sensors for November 2004 and 2006, respectively. The spatial variability of ETd was compared among different plant types, soil textural classes and depths using non-parametric statistical tests. In this comparison, the highest rates of ETd were obtained in the forest covers with values of 7.3 ± 0.8 and 8.4 ± 0.8 mm d−1 for 2004 and 2006, respectively. The lowest values were estimated for pastures and shrublands with values of 3.5 ± 1.2 mm d−1 and for crops with rates of 4.4 ± 1.6 mm d−1. Comparison of the ETd of the native forest covers and plantations of exotic species showed statistically significant differences; however...

Combining remote sensing and GIS climate modelling to estimate daily forest evapotranspiration in a Mediterranean mountain area

Cristóbal Rosselló, Jordi; Poyatos López, Rafael; Ninyerola i Casals, Miquel; Llorens García, Pilar; Pons, Xavier
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2011 Português
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Evapotranspiration monitoring allows us to assess the environmental stress on forest and agricultural ecosystems. Nowadays, Remote Sensing and Geographical Information Systems (GIS) are the main techniques used for calculating evapotranspiration at catchment and regional scales. In this study we present a methodology, based on the energy balance equation (B-method), that combines remote sensing imagery with GIS-based climate modelling to estimate daily evapotranspiration (ETd) for several dates between 2003 and 2005. The three main variables needed to compute ETd were obtained as follows: (i) Land surface temperature by means of the Landsat-5 TM and Landsat-7 ETM+ thermal band, (ii) air temperature by means of multiple regression analysis and spatial interpolation from meteorological ground stations data at satellite pass, and (iii) net radiation by means of the radiative balance. We calculated ETd using remote sensing data at different spatial and temporal scales (Landsat-7 ETM+, Landsat-5 TM and TERRA/AQUA MODIS, with a spatial resolution of 60, 120 and 1000 m, respectively) and combining three different approaches to calculate the B parameter, which represents an average bulk conductance for the daily-integrated sensible heat flux. We then compared these estimates with sap flow measurements from a Scots pine (Pinus sylvestris L.) stand in a Mediterranean mountain area. This procedure allowed us to better understand the limitations of ETd modelling and how it needs to be improved...