scholarly journals Occurrence and characterization of tremolite asbestos from the Mid Atlantic Ridge

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dario Di Giuseppe ◽  
Natale Perchiazzi ◽  
Daniele Brunelli ◽  
Tommaso Giovanardi ◽  
Luca Nodari ◽  
...  
Keyword(s):  
Structural Data ◽  
Ideal Crystal ◽  
Mineral Formation ◽  
Transform Fault ◽  
Fluid System ◽  
Cation Site ◽  
Physical Conditions ◽  
Mid Atlantic Ridge ◽  
The Ideal

AbstractTremolite is one of the most common amphibole species and, in the fibrous form (i.e., characterized by crystals/particles consisting of fibres with length > 5 µm, width < 3 µm and aspect ratio > 3), one of the six asbestos minerals. Until now the attention of crystallographers has focused only on samples from continental environment. Here we report the first chemical and structural data of a tremolite asbestos found along the Mid Atlantic Ridge (MAR) at the eastern intersection of the Romanche Transform Fault (Equatorial MAR). Tremolite is associated with chlorite and lizardite and was formed through the green shale facies lower than zeolite in a predominantly fluid system. MAR tremolite asbestos shows very slight deviations from the ideal crystal structure of tremolite. Differences in cation site partitioning were found with respect to tremolite asbestos from ophiolitic complexes, attributed to the different chemical–physical conditions during the mineral formation. In particular, oceanic tremolite asbestos is enriched in Al and Na, forming a trend clearly distinct from the continental tremolites.

The glycomes of Caenorhabditis elegans and other model organisms

2002 ◽  
Vol 69 ◽  
pp. 117-134 ◽  
Author(s):  
Stuart M. Haslam ◽  
David Gems ◽  
Howard R. Morris ◽  
Anne Dell
Keyword(s):  
Caenorhabditis Elegans ◽  
Current Knowledge ◽  
Structural Data ◽  
Model Organisms ◽  
Entire Genome ◽  
C Elegans ◽  
The Face ◽  
Area Of Concern ◽  
Nematode Worm

There is no doubt that the immense amount of information that is being generated by the initial sequencing and secondary interrogation of various genomes will change the face of glycobiological research. However, a major area of concern is that detailed structural knowledge of the ultimate products of genes that are identified as being involved in glycoconjugate biosynthesis is still limited. This is illustrated clearly by the nematode worm Caenorhabditis elegans, which was the first multicellular organism to have its entire genome sequenced. To date, only limited structural data on the glycosylated molecules of this organism have been reported. Our laboratory is addressing this problem by performing detailed MS structural characterization of the N-linked glycans of C. elegans; high-mannose structures dominate, with only minor amounts of complex-type structures. Novel, highly fucosylated truncated structures are also present which are difucosylated on the proximal N-acetylglucosamine of the chitobiose core as well as containing unusual Fucα1–2Gal1–2Man as peripheral structures. The implications of these results in terms of the identification of ligands for genomically predicted lectins and potential glycosyltransferases are discussed in this chapter. Current knowledge on the glycomes of other model organisms such as Dictyostelium discoideum, Saccharomyces cerevisiae and Drosophila melanogaster is also discussed briefly.

PRELIMINARY FORESHOCK ANALYSIS OF SUBMARINE TRANSFORM FAULT EARTHQUAKES ALONG THE EQUATORIAL MID-ATLANTIC RIDGE

2016 ◽  
Author(s):  
Ross P. Meyer ◽  
◽  
Joe H. Haxel ◽  
Robert P. Dziak ◽  
Deborah K. Smith
Keyword(s):  
Transform Fault ◽  
Mid Atlantic Ridge

Towards 3D image-based nanocrystallography by means of transmission electron goniometry

2004 ◽  
Vol 839 ◽  
Author(s):  
Peter Moeck ◽  
Wentao Qin ◽  
Philip B. Fraundorf
Keyword(s):  
Lattice Structure ◽  
Three Dimensions ◽  
Structural Defects ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Z Contrast ◽  
Individual Nanoparticles ◽  
Nanocrystal Model ◽  
The Ideal

ABSTRACTIt is well known that the crystallographic phase and morphology of many materials changes with the crystal size in the tens of nanometer range and that many nanocrystals possess structural defects in excess of their equilibrium levels. A need to determine the ideal and real structure of individual nanoparticles, therefore, arises. High-resolution phase-contrast transmission electron microscopy (TEM) and atomic resolution Z-contrast scanning TEM (STEM) when combined with transmission electron goniometry offer the opportunity of develop dedicated methods for the crystallographic characterization of nanoparticles in three dimensions. This paper describes tilt strategies for taking data from individual nanocrystals “as found”, so as to provide information on their lattice structure and orientation, as well as on the structure and orientation of their surfaces and structural defects. Internet based java applets that facilitate the application of this technique for cubic crystals with calibrated tilt-rotation and double-tilt holders are mentioned briefly. The enhanced viability of image-based nanocrystallography in future aberration-corrected TEMs and STEMs is illustrated on a nanocrystal model system.

Gobernanza económica europea y modelo territorial de distribución del poder

2013 ◽  
pp. 153-191
Author(s):  
Ainhoa LASA LÓPEZ
Keyword(s):  
European Union ◽  
The European Union ◽  
European Level ◽  
Euro Pean ◽  
Economic Constitution ◽  
The One ◽  
The Impact ◽  
The Relationship ◽  
The Ideal

LABURPENA: Artikulu honetan, Europar Batasuneko botere-artikulazio berriak erkidegotan osatutako Espainian zer eragin daukan aztertuko dugu. Europa mailako politika-ekonomia erlazioak funtsezko bi koordenatu izan behar ditu ezinbestean. Alde batetik, Europako konstituzio-ordena ez dela gizartearen konstituzionalismoaren koordenatuetan ernatutako ordenaren berdina. Bestetik, Europako konstituzio ekonomikoa Europa bat egiteko proiektuak berarekin dakartzan aldaketa berriak gorpuzteko eremua dela. Izan ere, funtsean, Europako konstituzio ekonomikoa plataforma ezin hobea delako boterearen artikulazioa berria nola artikulatu asmatzeko, Europa guztirako. RESUMEN: el objetivo de este artículo es analizar el impacto que tiene la nueva articulación del poder en la Unión Europea en el Estado español de las autonomías. La relación política-economía a nivel europeo debe tener en cuenta dos coordenadas fundamentales. Por una parte, la consideración del orden constitucional europeo como un orden distinto al gestado bajo las coordenadas del constitucionalismo social. Por otra, la caracterización de la constitución económica europea como ámbito de materialización de las nuevas transformaciones que incorpora el proyecto de integración europeo. Fundamentalmente, porque la constitución económica europea representa la plataforma idónea desde la que dilucidar la nueva articulación del poder desde el espacio supranacional europeo. ABSTRACT: The aim of this paper is to analyse the impact of the new articula tion of power in the European Union in the Spanish state of autonomies. The relationship between politics and economy at European level must take into consideration two fundamental coordinates. On the one hand, the Euro pean constitucional system appears as a system opposite to that of social constitutionalism. Moreover, the characterization of the European economic constitution as a field of realization of the new transformations incorporated by the European project. Specially, because this represents the ideal platform in order to analyse the new articulation of power from European supranational space.

scholarly journals Characterization of the nuclear export adaptor protein Nmd3 in association with the 60S ribosomal subunit

2010 ◽  
Vol 189 (7) ◽  
pp. 1079-1086 ◽  
Author(s):  
Jayati Sengupta ◽  
Cyril Bussiere ◽  
Jesper Pallesen ◽  
Matthew West ◽  
Arlen W. Johnson ◽  
...  
Keyword(s):  
Binding Site ◽  
Nuclear Export ◽  
Large Subunit ◽  
Ribosomal Subunit ◽  
Adaptor Protein ◽  
Structural Data ◽  
Release Mechanism ◽  
Nuclear Pore ◽  
Subunit Joining

The nucleocytoplasmic shuttling protein Nmd3 is an adaptor for export of the 60S ribosomal subunit from the nucleus. Nmd3 binds to nascent 60S subunits in the nucleus and recruits the export receptor Crm1 to facilitate passage through the nuclear pore complex. In this study, we present a cryoelectron microscopy (cryo-EM) reconstruction of the 60S subunit in complex with Nmd3 from Saccharomyces cerevisiae. The density corresponding to Nmd3 is directly visible in the cryo-EM map and is attached to the regions around helices 38, 69, and 95 of the 25S ribosomal RNA (rRNA), the helix 95 region being adjacent to the protein Rpl10. We identify the intersubunit side of the large subunit as the binding site for Nmd3. rRNA protection experiments corroborate the structural data. Furthermore, Nmd3 binding to 60S subunits is blocked in 80S ribosomes, which is consistent with the assigned binding site on the subunit joining face. This cryo-EM map is a first step toward a molecular understanding of the functional role and release mechanism of Nmd3.

scholarly journals Percepción de los entrenadores de alto rendimiento de atletismo: caracterización de su perfil polifacético (Perception of high performance track and field coaches: characterization of their multifaceted profile)

Retos ◽  
2015 ◽  
pp. 42-47
Author(s):  
Angeles Filgueira Perez
Keyword(s):  
High Performance ◽  
Target Population ◽  
Track And Field ◽  
Personal Qualities ◽  
High Level ◽  
Almost All ◽  
Methodological Aspects ◽  
The Ideal

En el presente estudio se ha tratado de obtener una aproximación al perfil ideal del entrenador de alto rendimiento en atletismo. En el mundo del deporte de alta competición, el entrenador debe desarrollar funciones de maestro, técnico y líder, lo cual hace difícil delimitar sus competencias (conocimientos, habilidades y cualidades personales). Por tanto, la principal motivación de este trabajo es establecer el papel que debe desempeñar el entrenador para la preparación física, técnica, táctica, psicológica y moral del deportista de alto nivel. Para ello, se ha considerado como población objeto de estudio al conjunto de entrenadores de alto rendimiento que en el momento de la investigación estuviesen activo, ya que interesaba realizar este estudio desde su propia perspectiva. Los datos recogidos forman parte de una investigación más amplia, llevada a cabo mediante encuesta, para la que se diseñó un cuestionario de 78 preguntas en el que se abarcaban tres temas: el perfil del entrenador y del deportista, así como la figura del formador de entrenadores en el Practicum. En este trabajo nos centramos en el primer tema y el análisis de la información obtenida nos permite concluir que la que práctica totalidad de los entrenadores de atletismo consideran necesario dominar con precisión los aspectos técnico-metodológicos. Además, consideran que su ética profesional debe estar regida por los principios de autonomía y beneficencia, de modo que valores como la honestidad y la justicia deben primar en el desarrollo de sus funciones.Abstract: In the current study, we have tried to get an approximation of the ideal profile of high performance coaches in athletics. In the high-level sports world, the coach must develop the role of teacher, technician and leader,  which makes it difficult to delimit  his/her competencies (knowledge, skills and personal qualities). Therefore, the main motivation of this work is to define the role that the coach plays in relation  to the physical, technical, tactical, psychological and moral preparation of elite athletes. Keeping this aim as an objective, we have considered as the target population the high performance coaches who are active at the time of the investigation, since we were interested  in knowing their own perspective. The data that was collected is a part of a wider investigation, conducted by a survey, for which we designed a questionnaire of 78 questions divided on three topics: the profile of the coach and the athlete, as well as the figure of the coach educator in the Practicum. In this work, we focus on the first topic and the analysis of the information that we obtained allows us to conclude that almost all the track and field coaches find it necessary to dominate the technical and methodological aspects. They also consider that professional ethics must be governed by the principles of autonomy and care that values   like honesty and justice must prevail in the performance of their work.

scholarly journals Biophysical characterization of the SARS-CoV-2 E protein

2021 ◽  
Author(s):  
Aujan Mehregan ◽  
Sergio Perez-Conesa ◽  
Yuxuan Zhuang ◽  
Ahmad Elbahnsi ◽  
Diletta Pasini ◽  
...  
Keyword(s):  
Recombinant Expression ◽  
Structural Data ◽  
Md Simulations ◽  
Full Length ◽  
Coarse Grained ◽  
Biophysical Characterization ◽  
Viral Budding ◽  
Nmr Structures ◽  
E Protein

SARS-CoV-2 is the virus responsible for the COVID-19 pandemic which continues to wreak havoc across the world, over a year and a half after its effects were first reported in the general media. Current fundamental research efforts largely focus on the SARS-CoV-2 Spike protein. Since successful antiviral therapies are likely to target multiple viral components, there is considerable interest in understanding the biophysical role of its other proteins, in particular structural membrane proteins. Here, we have focused our efforts on the characterization of the full-length E protein from SARS-CoV-2, combining experimental and computational approaches. Recombinant expression of the full-length E protein from SARS-CoV-2 reveals that this membrane protein is capable of independent multimerization, possibly as a tetrameric or smaller species. Fluorescence microscopy shows that the protein localizes intracellularly, and coarse-grained MD simulations indicate it causes bending of the surrounding lipid bilayer, corroborating a potential role for the E protein in viral budding. Although we did not find robust electrophysiological evidence of ion-channel activity, cells transfected with the E protein exhibited reduced intracellular Ca2+, which may further promote viral replication. However, our atomistic MD simulations revealed that previous NMR structures are relatively unstable, and result in models incapable of ion conduction. Our study highlights the importance of using high-resolution structural data obtained from a full-length protein to gain detailed molecular insights, and eventually permitting virtual drug screening.

scholarly journals Playing the Whack-A-Mole Game: ERK5 Activation Emerges Among the Resistance Mechanisms to RAF-MEK1/2-ERK1/2- Targeted Therapy

2021 ◽  
Vol 9 ◽  
Author(s):  
Alessandro Tubita ◽  
Ignazia Tusa ◽  
Elisabetta Rovida
Keyword(s):  
Tyrosine Kinases ◽  
Resistance Mechanism ◽  
Resistance Mechanisms ◽  
Mitogen Activated Protein Kinase ◽  
Cancer Therapies ◽  
New Era ◽  
Mitogen Activated Protein ◽  
The Impact ◽  
The Ideal

Molecularly tailored therapies have opened a new era, chronic myeloid leukemia being the ideal example, in the treatment of cancer. However, available therapeutic options are still unsatisfactory in many types of cancer, and often fail due to the occurrence of resistance mechanisms. With regard to small-molecule compounds targeting the components of the Mitogen-Activated Protein Kinase (MAPK) cascade RAF-MEK1/2-ERK1/2, these drugs may result ineffective as a consequence of the activation of compensatory pro-survival/proliferative signals, including receptor tyrosine kinases, PI3K, as well as other components of the MAPK family such as TPL2/COT. The MAPK ERK5 has been identified as a key signaling molecule in the biology of several types of cancer. In this review, we report pieces of evidence regarding the activation of the MEK5-ERK5 pathway as a resistance mechanism to RAF-MEK1/2-ERK1/2 inhibitors. We also highlight the known and possible mechanisms underlying the cross-talks between the ERK1/2 and the ERK5 pathways, the characterization of which is of great importance to maximize, in the future, the impact of RAF-MEK1/2-ERK1/2 targeting. Finally, we emphasize the need of developing additional therapeutically relevant MEK5-ERK5 inhibitors to be used for combined treatments, thus preventing the onset of resistance to cancer therapies relying on RAF-MEK1/2-ERK1/2 inhibitors.

scholarly journals Insights into AMS/PCAT transporters from biochemical and structural characterization of a double Glycine motif protease

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Silvia C Bobeica ◽  
Shi-Hui Dong ◽  
Liujie Huo ◽  
Nuria Mazo ◽  
Martin I McLaughlin ◽  
...  
Keyword(s):  
Structural Data ◽  
Leader Peptide ◽  
Gram Negative Bacteria ◽  
Protease Domain ◽  
Peptide Recognition ◽  
Gram Positive Bacteria ◽  
Dual Functional ◽  
Signaling Peptides

The secretion of peptides and proteins is essential for survival and ecological adaptation of bacteria. Dual-functional ATP-binding cassette transporters export antimicrobial or quorum signaling peptides in Gram-positive bacteria. Their substrates contain a leader sequence that is excised by an N-terminal peptidase C39 domain at a double Gly motif. We characterized the protease domain (LahT150) of a transporter from a lanthipeptide biosynthetic operon in Lachnospiraceae and demonstrate that this protease can remove the leader peptide from a diverse set of peptides. The 2.0 Å resolution crystal structure of the protease domain in complex with a covalently bound leader peptide demonstrates the basis for substrate recognition across the entire class of such transporters. The structural data also provide a model for understanding the role of leader peptide recognition in the translocation cycle, and the function of degenerate, non-functional C39-like domains (CLD) in substrate recruitment in toxin exporters in Gram-negative bacteria.

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