979 resultados para Tregoning, Larry


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A new species of Novantinoe Santos-Silva & Hovore 2007 is described from Panama. Modified key couplets including the new species are included.

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The Neoproterozoic post-collisional period in southern Brazil (650-580 Ma) is characterized by substantial volumes of magma emplaced along the active shear zones that compose the Southern Brazilian Shear Belt. The early-phase syntectonic magmatism (630-610 Ma) is represented by the porphyritic, high-K, metaluminous to peraluminous Quatro Ilhas Granitoids and the younger heterogranular, slightly peraluminous Mariscal Granite. Quatro II has Granitoids include three main petrographic varieties (muscovite-biotite granodiorite mbg; biotite monzogranite - bmz: and leucogranite - lcg) that, although sharing some significant geochemical characteristics, are not strictly comagmatic, as shown by chemical and Sr-Nd-Pb isotope data. The most primitive muscovite-biotite granodiorite was produced by contamination of more mafic melts (possibly with some mantle component) with peraluminous crustal melts; the biotite monzogranite, although more felsic, has higher Ca, MgO,TiO2 and Ba, and lower K2O, FeOt, Sr and Rb contents, possibly reflecting some mixing with coeval mafic magmas of tholeiitic affinity; the leucogranite may be derived from pure crustal melts. The Mariscal Granite is formed by two main granite types which occur intimately associated in the same pluton, one with higher K (5-6.5 wt.% K2O) high Rb and lower CaO, Na2O, Ba and Zr as compared to the other (3-5 wt.% of K2O). The two Mariscal Granite varieties have compositional correspondence with fine-grained granites (fgg) that occur as tabular bodies which intruded the Quatro Ilhas Granoitoids before they were fully crystallized, and are inferred to correspond to the Mariscal Granite feeders, an interpretation that is reinforced by similar U-Pb zircon crystallization ages. The initial evolution of the post-collisional magmatism, marked by the emplacement of the Quatro Ilhas Granitoids varieties, activated sources that produced mantle and crustal magmas whose emplacement was controlled both by flat-lying and transcurrent structures. The transition from thrust to transcurrent-related tectonics coincides with the increase in the proportion of crustal-derived melts. The transcurrent tectonics seems to have played an essential role in the generation of mantle-derived magmas and may have facilitated their interaction with crustal melts which seem to be to a large extent the products of reworking of orthogneiss protoliths. (C) 2012 Elsevier B.V. All rights reserved.

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Previous studies have shown that the DNA repair component Metnase (SETMAR) mediates resistance to DNA damaging cancer chemotherapy. Metnase has a nuclease domain that shares homology with the Transposase family. We therefore virtually screened the tertiary Metnase structure against the 550,000 compound ChemDiv library to identify small molecules that might dock in the active site of the transposase nuclease domain of Metnase. We identified eight compounds as possible Metnase inhibitors. Interestingly, among these candidate inhibitors were quinolone antibiotics and HIV integrase inhibitors, which share common structural features. Previous reports have described possible activity of quinolones as antineoplastic agents. Therefore, we chose the quinolone ciprofloxacin for further study, based on its wide clinical availability and low toxicity. We found that ciprofloxacin inhibits the ability of Metnase to cleave DNA and inhibits Metnase-dependent DNA repair. Ciprofloxacin on its own did not induce DNA damage, but it did reduce repair of chemotherapy-induced DNA damage. Ciprofloxacin increased the sensitivity of cancer cell lines and a xenograft tumor model to clinically relevant chemotherapy. These studies provide a mechanism for the previously postulated antineoplastic activity of quinolones, and suggest that ciprofloxacin might be a simple yet effective adjunct to cancer chemotherapy. Cancer Res; 72(23); 6200-8. (C) 2012 AACR.

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Giesberteclipta and Thomasella, two new genera of Rhinotragini Thomson, 1861 (Coleoptera: Cerambycidae: Cerambycinae), are described and illustrated. Six new species are also described and illustrated: Acyphoderes violaceus from Costa Rica; Ischasioides giesberti from Ecuador, and Oxylymma pallida, Pseudagaone williamsi, Stultutragus tippmanni and S. ventriguttatus from Brazil. Keys are provided for the known species of Pseudagaone Tippmann, 1960, Giesberteclipta, and Oxylymma Pascoe, 1859 and for parts of Ischasioides Tavakilian & Penaherrera-Leiva, 2003 and Stultutragus Clarke, 2010. The following new combinations are proposed: Giesberteclipta costipennis (Giesbert, 1991); G. monteverdensis (Giesbert, 1991); Thomasella igniventris (Giesbert, 1991), and Stultutragus romani (Aurivillius, 1919). The following three new country records are reported: Oxylymma durantoni Penaherrera-Leiva & Tavakilian, 2003 (Brazil), Oxylymma sudrei Penaherrera-Leiva & Tavakilian, 2003 (Brazil), and Ommata (Eclipta) faurei Penaherrera-Leiva & Tavakilian, 2003, all from Brazil.

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LA-MC-ICP-MS U-Pb zircon dating was performed on syntectonic, early post-collisional granitic and associated mafic rocks that are intrusive in the Brusque Metamorphic Complex and in the Florianopolis Batholith, major tectonic domains separated by the Neoproterozoic Major Gercino Shear Zone (MGSZ) in south Brazil. The inferred ages of magmatic crystallization are consistent with field relationships, and show that the syntectonic granites from both domains are similar, with ages around 630-620 Ma for high-K calc-alkaline metaluminous granites and ca. 610 Ma for slightly peraluminous granites. Although ca. 650 Ma inherited zircon components are identified in granites from both domains, important contrasts on the crustal architecture in each domain are revealed by the patterns of zircon inheritance, indicating different crustal sources for the granites in each domain. The granites from the southern domain (Floriandpolis Batholith) have essentially Neoproterozoic (650-700 Ma and 900-950 Ma) inheritance; with a single 2.0-2.2 Ga inherited age obtained in the peraluminous Mariscal Granite. In the northern Brusque Metamorphic Complex, the metaluminous Rio Pequeno Granite and associated mafic rocks have scarce inherited cores with ages around 1.65 Ga, whereas the slightly peraluminous Serra dos Macacos Granite has abundant Paleoproterozoic (1.8-2.2 Ga) and Archean (2.9-3.4 Ga) inherited zircons. Our results are consistent with the hypothesis that the MGSZ separates domains with distinct geologic evolution; however, the contemporaneity of 630-610 Ma granitic magmatism with similar structural and geochemical patterns on both sides of this major shear zone indicates that these domains were already part of a single continental mass at 630 Ma, reinforcing the post-collisional character of these granites. (C) 2012 Elsevier B.V. All rights reserved.

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Abstract Background The mitochondrial DNA of kinetoplastid flagellates is distinctive in the eukaryotic world due to its massive size, complex form and large sequence content. Comprised of catenated maxicircles that contain rRNA and protein-coding genes and thousands of heterogeneous minicircles encoding small guide RNAs, the kinetoplast network has evolved along with an extreme form of mRNA processing in the form of uridine insertion and deletion RNA editing. Many maxicircle-encoded mRNAs cannot be translated without this post-transcriptional sequence modification. Results We present the complete sequence and annotation of the Trypanosoma cruzi maxicircles for the CL Brener and Esmeraldo strains. Gene order is syntenic with Trypanosoma brucei and Leishmania tarentolae maxicircles. The non-coding components have strain-specific repetitive regions and a variable region that is unique for each strain with the exception of a conserved sequence element that may serve as an origin of replication, but shows no sequence identity with L. tarentolae or T. brucei. Alternative assemblies of the variable region demonstrate intra-strain heterogeneity of the maxicircle population. The extent of mRNA editing required for particular genes approximates that seen in T. brucei. Extensively edited genes were more divergent among the genera than non-edited and rRNA genes. Esmeraldo contains a unique 236-bp deletion that removes the 5'-ends of ND4 and CR4 and the intergenic region. Esmeraldo shows additional insertions and deletions outside of areas edited in other species in ND5, MURF1, and MURF2, while CL Brener has a distinct insertion in MURF2. Conclusion The CL Brener and Esmeraldo maxicircles represent two of three previously defined maxicircle clades and promise utility as taxonomic markers. Restoration of the disrupted reading frames might be accomplished by strain-specific RNA editing. Elements in the non-coding region may be important for replication, transcription, and anchoring of the maxicircle within the kinetoplast network.

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Ziel dieser Arbeit ist es, einen Beitrag zur Klärung des Zusammenhangs zwischen Medienfreiheit und Demokratie, der zwar weitläufig postuliert, aber dennoch lediglich in geringem Maße erforscht ist, zu leisten und insbesondere die konzeptionelle Rückbindung von Medienfreiheit an die Demokratietheorie zu verbessern. Es wird davon ausgegangen, dass eine Demokratie ohne die Verwirklichung von Medienfreiheit nicht funktionieren kann. Medienfreiheit wird daher als ein Merkmal von Demokratie aufgefasst. Im ersten Teil der Arbeit wird, ausgehend von Larry Diamonds Konzeption einer liberalen Demokratie, eine konkrete Definition und Konzeptualisierung von Medienfreiheit herausgearbeitet. Damit wird ein Maßstab formuliert, der im Folgenden dazu dient existierende Messungen von Medienfreiheit auf ihren konzeptuellen Gehalt hin zu überprüfen. Im zweiten Teil werden existierende Indizes bezüglich ihrer Messung von Medienfreiheit evaluiert. Betrachtet werden hierbei sowohl zwei Demokratieindizes (der Index Politische Rechte und Bürgerliche Freiheiten von Freedom House sowie der Index Liberale Demokratie aus dem Varieties of Democracy-Projekt) als auch zwei Indizes, die explizit Medienfreiheit messen (der Index Pressefreiheit von Freedom House sowie die Rangliste der Pressefreiheit von Reporter ohne Grenzen).

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Imaging studies show entrapment of the left renal vein in the fork between the aorta and proximal superior mesenteric artery in most cases of isolated postural proteinuria. Therefore, it has been postulated that partial obstruction to the flow in the left renal vein in the upright position is a cause of this form of proteinuria. In a girl with isolated postural proteinuria, kidney ultrasonic imaging and Doppler flow scanning showed left renal vein entrapment. Seven years later, a new evaluation showed resolution of both postural proteinuria and left renal vein entrapment. The longitudinal observation provides substantial additional support for entrapment of the left renal vein by the aorta and superior mesenteric artery as a cause of isolated postural proteinuria.

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Two strains of guinea pig develop spontaneous osteoarthritis of the knee. Although the disease evolves at different rates in the two strains, it is not known whether these differences are reflected in the structure of the cartilage and cancellous bone.

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Context During the past 2 decades, a major transition in the clinical characterization of psychotic disorders has occurred. The construct of a clinical high-risk (HR) state for psychosis has evolved to capture the prepsychotic phase, describing people presenting with potentially prodromal symptoms. The importance of this HR state has been increasingly recognized to such an extent that a new syndrome is being considered as a diagnostic category in the DSM-5. Objective To reframe the HR state in a comprehensive state-of-the-art review on the progress that has been made while also recognizing the challenges that remain. Data Sources Available HR research of the past 20 years from PubMed, books, meetings, abstracts, and international conferences. Study Selection and Data Extraction Critical review of HR studies addressing historical development, inclusion criteria, epidemiologic research, transition criteria, outcomes, clinical and functional characteristics, neurocognition, neuroimaging, predictors of psychosis development, treatment trials, socioeconomic aspects, nosography, and future challenges in the field. Data Synthesis Relevant articles retrieved in the literature search were discussed by a large group of leading worldwide experts in the field. The core results are presented after consensus and are summarized in illustrative tables and figures. Conclusions The relatively new field of HR research in psychosis is exciting. It has the potential to shed light on the development of major psychotic disorders and to alter their course. It also provides a rationale for service provision to those in need of help who could not previously access it and the possibility of changing trajectories for those with vulnerability to psychotic illnesses.

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