35 research outputs found

    Lindane and Endosulfan Sulfate Isomers in Crassostrea virginica (Gmelin, 1791) Oyster Populations in Lagoon Systems from Central Gulf of Mexico

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    The aim of this study was to determine Lindane and Endosulfan Sulfate isomers in Crassostrea virginica oyster populations (Gmelin, 1791) in the Mandinga and Alvarado lagoon systems located in the central Gulf of Mexico. Samples were taken from the main oyster banks of each lagoon system, during the three representative seasons of the region, wet, dry and north winds. By means of free diving, 30 commercial size oysters (7 ± 3 cm) were collected in four oyster banks or stations of the Mandinga lagoon system, totaling 360 organisms, while in the Alvarado lagoon system there were a total of 90 oysters during the annual cycle. Concentration of lindane and endosulfan sulfate isotopes in C. virginica was performed with a gas chromatograph (Thermo Electron Model Trace GC Ultra 115V, Thermo Fisher Scientific Inc©, Monterrey, Nuevo León, México) with an Electron capture detector. Results showed that in the Alvarado Lagoon system mean concentrations of C. virginica oysters for lindane pesticide were 4.11 ± 3.83 ng⋅g-1, whereas for the Mandinga lagoon system, were 8.69 ± 5.15 ng⋅g-1. Endosulfan sulfate showed the highest average concentration in the Mandinga lagoon system with 24.68 ± 1.20 ng ⋅g-1. In addition, the endosulfan sulfate presents differences in its spatial distribution; high concentration levels in the Mandinga lagoon system whereas the lindane heterogeneity at all sampling points in both lagoons. Values of concentrations and relationships between compounds suggest recent contributions that could correspond to the excessive fluctuations of water discharged into the lagoon caused by the atypical rains of the year of sampling. It was concluded that endosulfan sulfate and lindane show concentration in all the points of sampling in both lagoons

    Dynamic interaction of SARAF with STIM1 and orai1 to modulate store-operated calcium entry

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    El flujo de Ca2+ por almacenado por canales de Ca2+ es un mecanismo importante para la homeostasis intracelular de Ca2+ y la función celular. Aquí presentamos la evidencia de la interacción dinámica entre el factor regulador asociado SOCE (SARAF), STIM1 y Orai1. La expresión atenuada SARAF y la interacción SOCE STIM1-Orai1 en células expresan endógenamente a STIM1 y Orai1 mientras RNAi está condicionada por silenciamiento de SARAF induciendo efectos opuestos. SARAF menoscaba la asociación entre Orai1 y la activación de Orai1 del pequeño fragmento de STIM1 expresada en la STIM1-L115-401NG deficiente de células. En tratamiento de la celda con agonistas o thapsigargin fisiológico resulta en asociación directa de SARAF con Orai1. La interacción de ESTIMI1 independiente de SARAF con Orai1 conduce a la activación de este canal. Las células expresan endógenamente STIM1 y el agotamiento del almacenado de Orai1, Ca2+ conduce a la disociación de SARAF de STIM1 a los 30 segundos después del tratamiento con thapsigargin, paralelo al aumento de SARAF en la interacción con Orai1, seguido por reinteracción con STIM1 y la disociación desde Orai1. La expresión de SARAF y Orai1 o la supresión de diversos N-terminal de mutantes de Orai1 no altera la interacción de SARAF-Orai1; sin embargo, la expresión de eliminación de C-terminal y los mutantes de Orai1 bloquean la C-terminal de Orai1 y menoscaban la interacción con SARAF. Estas observaciones sugieren que SARAF ejerce un papel positivo inicial en la activación de SOCE seguida por la facilitación del SCDI de Orai1.Ca2+ influx by store-operated Ca2+ channels is a major mechanism for intracellular Ca2+ homeostasis and cellular function. Here we present evidence for the dynamic interaction between the SOCE associated regulatory factor (SARAF), STIM1 and Orai1. SARAF overexpression attenuated SOCE and the STIM1-Orai1 interaction in cells endogenously expressing STIM1 and Orai1 while RNAi-mediated SARAF silencing induced opposite effects. SARAF impaired the association between Orai1 and the Orai1-activating small fragment of STIM1 co-expressed in the STIM1-deficient NG115-401L cells. Cell treatment with thapsigargin or physiological agonists results in direct association of SARAF with Orai1. STIM1-independent interaction of SARAF with Orai1 leads to activation of this channel. In cells endogenously expressing STIM1 and Orai1, Ca2+ store depletion leads to dissociation of SARAF withSTIM1 approximately 30s after treatment with thapsigargin, which paralleled the increase in SARAFOrai1 interaction, followed by reinteraction with STIM1 and dissociation from Orai1. Co-expression of SARAF and either Orai1 or various N-terminal deletion Orai1 mutants did not alter SARAF-Orai1 interaction; however, expression of C-terminal deletion Orai1 mutants or blockade of the C-terminus of Orai1 impair the interaction with SARAF. These observations suggest that SARAF exerts an initial positive role in the activation of SOCE followed by the facilitation of SCDI of Orai1.• Ministerio de Economía y Competitividad. Becas BFU2013-45564-C2-1-P, BFU2013-45564-C2-2-P, BFU2011-24365 and RD12-0043-0016 (RETICEF) • Ministerio de Economía y Competitividad. Programa Juan de la Cierva para José Javier López Barba • Ministerio de Economía y Competitividad. Beca BES-2011-043356 para Letizia Albarrán Alonso • Junta de Extremadura y Fondos FEDERpeerReviewe

    EFHB is a novel cytosolic Ca²+ sensor that modulates STIM1-SARAF interaction

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    FUNDAMENTOS/OBJETIVOS: STIM1 y Orai1 son los componentes clave de la entrada de Ca2+ en la tienda (SOCE). Entre las proteínas que participan en la regulación de la SOCE, la SARAF previene la activación espontánea de la SOCE y modula la función de STIM1. MÉTODOS: Se estimó la movilización de Ca2+ citosólico en células cargadas de fura-2 usando un microscopio invertido de epifluorescencia. La interacción de STIM1 con Orai1, EFHB (miembro de la familia B del dominio de la mano EF, también conocido como CFAP21) y SARAF se detectó mediante inmunoprecipitación seguida de Western blotting utilizando anticuerpos específicos. La participación de EFHB en la translocación de NFAT al núcleo se detectó mediante microscopía confocal. RESULTADOS: Aquí reportamos la identificación del EFHB como un nuevo regulador SOCE. El EFHB interactúa con el STIM1 al agotarse el almacenamiento y se disocia a través de un mecanismo dependiente de Ca2+-. El silenciamiento mediado por el ARNi así como los estudios de sobreexpresión revelaron que el EFHB juega un papel relevante en la interacción de STIM1 y Orai1 al agotarse las reservas, la activación de la translocación de SOCE y NFAT del citosol al núcleo. El silenciamiento de la expresión de la EFHB suprimió la disociación de la SARAF de la STIM1, lo que indica que la EFHB podría desempeñar un papel importante en la interacción dinámica entre ambas proteínas, lo que es pertinente para la activación de los canales de Orai1 al agotarse el almacenamiento de Ca2+ y su posterior modulación mediante la inactivación lenta dependiente del Ca2+. CONCLUSIÓN: Nuestros resultados indican que el EFHB es un nuevo regulador SOCE que modula la interacción STIM1-SARAF.BACKGROUND/AIMS: STIM1 and Orai1 are the key components of store-operated Ca2+ entry (SOCE). Among the proteins involved in the regulation of SOCE, SARAF prevents spontaneous activation of SOCE and modulates STIM1 function. METHODS: Cytosolic Ca2+ mobilization was estimated in fura-2-loaded cells using an epifluorescence inverted microscope. STIM1 interaction with Orai1, EFHB (EF-hand domain family member B, also known as CFAP21) and SARAF was detected by immunoprecipitation followed by Western blotting using specific antibodies. The involvement of EFHB in the translocation of NFAT to the nucleus was detected by confocal microscopy. RESULTS: Here, we report the identification of EFHB as a new SOCE regulator. EFHB interacts with STIM1 upon store depletion and dissociates through a Ca2+- dependent mechanism. RNAi-mediated silencing as well as overexpression studies revealed that EFHB plays a relevant role in the interaction of STIM1 and Orai1 upon store depletion, the activation of SOCE and NFAT translocation from the cytosol to the nucleus. Silencing EFHB expression abolished the dissociation of SARAF from STIM1, which indicates that EFHB might play an important role in the dynamic interaction between both proteins, which is relevant for the activation of Orai1 channels upon Ca2+ store depletion and their subsequent modulation via slow Ca2+-dependent inactivation. CONCLUSION: Our results indicate that EFHB is a new SOCE regulator that modulates STIM1-SARAF interaction.• Ministerio de Economía y Competitividad. Contrato Juan de la Cierva IJCI-2015-25665, para Isaac Jardín Polo • Junta de Extremadura y Fondos FEDER. Contrato IB16046, para José Javier López Barba • Ministerio de Economía y Competitividad. Subvención BFU2016-74932-C2-1-P, para Letizia Albarrán Alonso • Ministerio de Economía y Competitividad. Subvenciones Subvenciones BFU2013-45564-C2-1-P/2-P y BFU2016-74932-C2-1-P/2-P • Junta de Extremadura y Fondos FEDER. Subvenciones IB16046 y GR18061peerReviewe

    Transcriptome profiling of grapevine seedless segregants during berry development reveals candidate genes associated with berry weight

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    Indexación: Web of Science; PubMedBackground Berry size is considered as one of the main selection criteria in table grape breeding programs. However, this is a quantitative and polygenic trait, and its genetic determination is still poorly understood. Considering its economic importance, it is relevant to determine its genetic architecture and elucidate the mechanisms involved in its expression. To approach this issue, an RNA-Seq experiment based on Illumina platform was performed (14 libraries), including seedless segregants with contrasting phenotypes for berry weight at fruit setting (FST) and 6–8 mm berries (B68) phenological stages. Results A group of 526 differentially expressed (DE) genes were identified, by comparing seedless segregants with contrasting phenotypes for berry weight: 101 genes from the FST stage and 463 from the B68 stage. Also, we integrated differential expression, principal components analysis (PCA), correlations and network co-expression analyses to characterize the transcriptome profiling observed in segregants with contrasting phenotypes for berry weight. After this, 68 DE genes were selected as candidate genes, and seven candidate genes were validated by real time-PCR, confirming their expression profiles. Conclusions We have carried out the first transcriptome analysis focused on table grape seedless segregants with contrasting phenotypes for berry weight. Our findings contributed to the understanding of the mechanisms involved in berry weight determination. Also, this comparative transcriptome profiling revealed candidate genes for berry weight which could be evaluated as selection tools in table grape breeding programs.http://bmcplantbiol.biomedcentral.com/articles/10.1186/s12870-016-0789-

    Dissipation of Knowledge and the Boundaries of the Multinational Enterprise

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    Tras los pasos de la Sílfide. Imaginarios españoles del ballet romántico a la danza moderna

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    La publicación que tiene la persona lectora entre sus manos realiza un recorrido de cien años de historia de la danza, un camino que toma como punto de partida la cultura visual del Romanticismo y que se ramifica fuera del ámbito geográfico de nuestro país, analizando los rasgos que definen y construyen la danza española y cómo estos se difundieron en los bailes en el extranjero.Las investigaciones contenidas en este libro son resultado del proyecto Tras los pasos de la Sílfide. Una historia de la danza en España, 1836-1936 (PGC2018-093710-A-I00)Peer reviewe

    Suppressing quantum errors by scaling a surface code logical qubit

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    Practical quantum computing will require error rates that are well below what is achievable with physical qubits. Quantum error correction offers a path to algorithmically-relevant error rates by encoding logical qubits within many physical qubits, where increasing the number of physical qubits enhances protection against physical errors. However, introducing more qubits also increases the number of error sources, so the density of errors must be sufficiently low in order for logical performance to improve with increasing code size. Here, we report the measurement of logical qubit performance scaling across multiple code sizes, and demonstrate that our system of superconducting qubits has sufficient performance to overcome the additional errors from increasing qubit number. We find our distance-5 surface code logical qubit modestly outperforms an ensemble of distance-3 logical qubits on average, both in terms of logical error probability over 25 cycles and logical error per cycle (2.914%±0.016%2.914\%\pm 0.016\% compared to 3.028%±0.023%3.028\%\pm 0.023\%). To investigate damaging, low-probability error sources, we run a distance-25 repetition code and observe a 1.7×1061.7\times10^{-6} logical error per round floor set by a single high-energy event (1.6×1071.6\times10^{-7} when excluding this event). We are able to accurately model our experiment, and from this model we can extract error budgets that highlight the biggest challenges for future systems. These results mark the first experimental demonstration where quantum error correction begins to improve performance with increasing qubit number, illuminating the path to reaching the logical error rates required for computation.Comment: Main text: 6 pages, 4 figures. v2: Update author list, references, Fig. S12, Table I

    Measurement-induced entanglement and teleportation on a noisy quantum processor

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    Measurement has a special role in quantum theory: by collapsing the wavefunction it can enable phenomena such as teleportation and thereby alter the "arrow of time" that constrains unitary evolution. When integrated in many-body dynamics, measurements can lead to emergent patterns of quantum information in space-time that go beyond established paradigms for characterizing phases, either in or out of equilibrium. On present-day NISQ processors, the experimental realization of this physics is challenging due to noise, hardware limitations, and the stochastic nature of quantum measurement. Here we address each of these experimental challenges and investigate measurement-induced quantum information phases on up to 70 superconducting qubits. By leveraging the interchangeability of space and time, we use a duality mapping, to avoid mid-circuit measurement and access different manifestations of the underlying phases -- from entanglement scaling to measurement-induced teleportation -- in a unified way. We obtain finite-size signatures of a phase transition with a decoding protocol that correlates the experimental measurement record with classical simulation data. The phases display sharply different sensitivity to noise, which we exploit to turn an inherent hardware limitation into a useful diagnostic. Our work demonstrates an approach to realize measurement-induced physics at scales that are at the limits of current NISQ processors

    Non-Abelian braiding of graph vertices in a superconducting processor

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    Indistinguishability of particles is a fundamental principle of quantum mechanics. For all elementary and quasiparticles observed to date - including fermions, bosons, and Abelian anyons - this principle guarantees that the braiding of identical particles leaves the system unchanged. However, in two spatial dimensions, an intriguing possibility exists: braiding of non-Abelian anyons causes rotations in a space of topologically degenerate wavefunctions. Hence, it can change the observables of the system without violating the principle of indistinguishability. Despite the well developed mathematical description of non-Abelian anyons and numerous theoretical proposals, the experimental observation of their exchange statistics has remained elusive for decades. Controllable many-body quantum states generated on quantum processors offer another path for exploring these fundamental phenomena. While efforts on conventional solid-state platforms typically involve Hamiltonian dynamics of quasi-particles, superconducting quantum processors allow for directly manipulating the many-body wavefunction via unitary gates. Building on predictions that stabilizer codes can host projective non-Abelian Ising anyons, we implement a generalized stabilizer code and unitary protocol to create and braid them. This allows us to experimentally verify the fusion rules of the anyons and braid them to realize their statistics. We then study the prospect of employing the anyons for quantum computation and utilize braiding to create an entangled state of anyons encoding three logical qubits. Our work provides new insights about non-Abelian braiding and - through the future inclusion of error correction to achieve topological protection - could open a path toward fault-tolerant quantum computing
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