88 research outputs found

    The PII-NAGK-PipX-NtcA Regulatory Axis of Cyanobacteria: A Tale of Changing Partners, Allosteric Effectors and Non-covalent Interactions

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    PII, a homotrimeric very ancient and highly widespread (bacteria, archaea, plants) key sensor-transducer protein, conveys signals of abundance or poorness of carbon, energy and usable nitrogen, converting these signals into changes in the activities of channels, enzymes, or of gene expression. PII sensing is mediated by the PII allosteric effectors ATP, ADP (and, in some organisms, AMP), 2-oxoglutarate (2OG; it reflects carbon abundance and nitrogen scarcity) and, in many plants, L-glutamine. Cyanobacteria have been crucial for clarification of the structural bases of PII function and regulation. They are the subject of this review because the information gathered on them provides an overall structure-based view of a PII regulatory network. Studies on these organisms yielded a first structure of a PII complex with an enzyme, (N-acetyl-Lglutamate kinase, NAGK), deciphering how PII can cause enzyme activation, and how it promotes nitrogen stockpiling as arginine in cyanobacteria and plants. They have also revealed the first clear-cut mechanism by which PII can control gene expression. A small adaptor protein, PipX, is sequestered by PII when nitrogen is abundant and is released when is scarce, swapping partner by binding to the 2OG-activated transcriptional regulator NtcA, co-activating it. The structures of PII-NAGK, PII-PipX, PipX alone, of NtcA in inactive and 2OG-activated forms and as NtcA-2OG-PipX complex, explain structurally PII regulatory functions and reveal the changing shapes and interactions of the T-loops of PII depending on the partner and on the allosteric effectors bound to PII. Cyanobacterial studies have also revealed that in the PII-PipX complex PipX binds an additional transcriptional factor, PlmA, thus possibly expanding PipX roles beyond NtcA-dependency. Further exploration of these roles has revealed a functional interaction of PipX with PipY, a pyridoxal-phosphate (PLP) protein involved in PLP homeostasis whose mutations in the human ortholog cause epilepsy. Knowledge of cellular levels of the different components of this PII-PipX regulatory network and of KD values for some of the complexes provides the basic background for gross modeling of the system at high and low nitrogen abundance. The cyanobacterial network can guide searches for analogous components in other organisms, particularly of PipX functional analogs

    Nuevas obtenciones de plantas libres de virus de materiales frutales autóctonos de Murcia

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    En un trabajo previo se obtuvieron plantas libres de virus de 13 clones de melocotonero infectados por "apple chlorotic leaf spot virus" (ACLSV), mediante la técnica del microinjerto de ápices caulinares in vitro, En el presente trabajo, la aplicación del microinjerto ha permitido obtener plantas libres de virus de los siguientes materiales autóctonos de Murcia: - Diez nuevos clones de melocotonero infectados por ACLSV. - Un clon de melocotonero y un clon de híbrido melocotonero x almendro infectados por "prunus necrotic ring spot virus" (PNRSV). - Tres clones de melocotonero infectados simultáneamente por PNRSV y ACLSV, más otro clon infectado por PNRSV, ACLSV y "prune dwarf virus" (PDV). Se han obtenido también plantas libres de ACLSV de 5 clones de ciruelo Pollizo, mediante injerto en verano sobre patrones sanos, aprovechando la irregular distribución de este virus en dicha época del año

    Análisis de las pérdidas de propagación medidas en una plantación de cítricos en las bandas de 1800 MHz, 2100 MHz, 3.5 GHz y 28 GHz en una situación de LoS

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    [EN] Agriculture 4.0 is going to represent a massive deployment of sensors, so efficient planning of radiocommunication systems in this type of environment will be necessary. In this work, the measured path loss in a LoS situation, with the transmitter and receiver heights below the trees height, at a citrus plantation in the 1800MHz, 2100MHz, 3.5GHz and 28GHz frequency bands using the FI (Floating Intercept) and the CI (Close-In reference) models has been analyzed. It has been observed that from 3.5GHz, the slope of the FI model also represents the propagation exponent (PLE). Furthermore, a guiding effect (PLE less than 2) has been observed in the 1800MHz and 2100MHz bands, not in the 3.5GHz and 28GHz bands, in which the PLE is practically equal to 2 (free space). Finally, the analysis of the polarization reveals that the standard deviation of the measured values with respect to the values obtained from the models is greater for horizontal than vertical polarization in the 1800MHz and 2100MHz frequency bands.Este trabajo ha sido financiado por la Comunidad Autónoma de la Región de Murcia a través del proyecto 20804/PI/18 de la convocatoria de Ayudas a proyectos para el desarrollo de investigación científica y técnica por grupos competitivos, incluida en el Programa Regional de Fomento de la Investigación (Plan de Actuación 2019) de la Fundación Séneca, Agencia de Ciencia y Tecnología de la Región de Murcia y por el Ministerio de Economía y Competitividad MINECO (PID2019-107885GB-C33).Juan-Llácer, L.; Martínez Rubiola, L.; Molina-García-Pardo, JM.; Martínez-Inglés, MT.; Rodríguez, J.; Pascual-García, J.; Cabedo Fabres, M.... (2021). Análisis de las pérdidas de propagación medidas en una plantación de cítricos en las bandas de 1800 MHz, 2100 MHz, 3.5 GHz y 28 GHz en una situación de LoS. Íñigo Cuiñas Gómez. 1-4. http://hdl.handle.net/10251/1910861

    Base de datos multicéntrica de hemorragia subaracnoidea espontánea del Grupo de Trabajo de Patología Vascular de la Sociedad Española de Neurocirugía: presentación,criterios de inclusión y desarrollo de una base de datos en internet = Spontaneous Subarachnoid Haemorrhage multicenter database from the Group for the Study of Vascular Pathology of the Spanish Society for Neurosurgery: Presentation, inclusion criteria and development of an internet-based registry

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    Introducción. La hemorragia subaracnoidea (HSA) continúa siendo una de las enfermedades de interés neuroquirúrgico de más alta morbilidad y mortalidad. Su estudio es clave a la hora de mejorar la atención de estos enfermos en nuestro medio. Con este fin el Grupo de Trabajo de Patología Vascular de la SENEC decidió la creación de una base de datos multicéntrica para su estudio. Material y métodos. Se incluyen en esta base de datos todos los casos de hemorragia subaracnoidea espontánea ingresados en los centros participantes de forma prospectiva desde Noviembre del año 2004 hasta Noviembre del 2007. Se decidieron de forma consensuada los campos a recoger incluyendo edad, antecedentes personales, características clínicas, características radiológicas y del aneurisma, tipo de tratamiento y complicaciones de la enfermedad, evolución según la escala de evolución de Glasgow (GOS) al alta y a los seis meses así como el resultado angiográfico del tratamiento. Todos los campos se recogieron en un formulario rellenable a través de una página web segura. Resultados. En los tres años en los que ha estado activa la base se han recogido un total de 1149 casos de HSA espontánea recogidos por 14 centros participantes. Se ha estimado que es necesario aproximadamente un tiempo de 3.4 minutos para rellenar cada caso. En cuanto a sus características generales la serie es similar a otras series hospitalarias no seleccionadas. La edad media de los enfermos incluidos es de unos 55 años y la relación mujer:hombre 4:3. En cuanto a la gravedad del sagrado inicial un 32% de los enfermos se encontraba en mal grado clínico (WFNS = 4 ó 5). El 5% de los pacientes fallecieron antes de realizarse una angiografía que confirmara el origen aneurismático del sangrado. Se confirmó el origen aneurismático en el 76% de los pacientes mientras que en el 19% no se encontró ninguna lesión vascular responsable del sangrado, siendo clasificados como HSA idiopática. En los pacientes en los que se detectó un aneurisma su tratamiento fue endovascular en el 47% de los casos, quirúrgico en el 39, mixto en el 3% y no recibieron tratamiento de su aneurisma el 11% de los pacientes por fallecimiento precoz. En cuanto a su evolución, la mortalidad global de la serie se sitúa en el 22%. Sólo el 40% de los enfermos con HSA aneurismática presentaron una buena evolución (GOS=5). Conclusiones. La HSA espontánea continúa siendo una enfermedad con alta morbilidad y mortalidad. Esta base de datos puede ser un instrumento para conocer mejor sus características en nuestro medio y mejorar sus resultados, ya que se trata de una serie multicéntrica hospitalaria no seleccionada. Sería pues recomendable que esta base constituyera el germen de un registro nacional de HSA espontánea. Introduction. Subarachnoid haemorrhage is one of the most severe neurosurgical diseases. Its study is crucial for improving the care of these patients in our environment. With this goal the Group for the Study of Neurovascular Pathology of the Spanish Society for Neurosurgery (SENEC) decided to create a multicenter registry for the study of this disease. Materials and methods. In this database we have prospectively included all cases with spontaneous subarachnoid haemorrhage admitted to the participant hospitals from November 2004 to November 2007. The fields to be included in the database were selected by consensus, including age, past medical history, clinical characteristics at admission, radiological characteristics including presence or absence of an aneurysm and its size and location, type and complications of the aneurysm treatment, outcome assessed by the Glasgow Outcome Scale (GOS) at discharge and six months after the bleeding as well as the angiographic result of the aneurysm treatment. All fields were collected by means of an electronic form posted in secure web page. Results. During the three years of study a total of 1149 patients have been included by 14 Hospitals. The time needed to fill in a patient in the registry is approximately 3.4 minutes. This series of patients with spontaneous SAH is similar to other non-selected in-hospital series of SAH. The mean age of the patients is 55 years and there is a 4:3 female to male ratio. In relation to the severity of the bleeding 32% of the patients were in poor clinical grade at admission (WFNS 4 or 5). 5% of the patients died before angiography could be performed. An aneurysm was confirmed as the origin of the bleeding in 76% of the patients (aSAH), while in 19% of the patients no lesion was found in the angiographic studies and were thus classified as idiopathic subarachnoid hemorrhage (ISAH). Of those patients with aSAH, 47% were treated endovascularly, 39% surgically, 3% received a combined treatment and 11% did not receive any treatment for their aneurysm because of early death. Regarding outcome, there is a 22% mortality in the series. Only 40% of the patients with aSAH reached a good outcome at discharge (GOS = 5). Conclusions. Spontaneous SAH continues to be a disease with high morbidity and mortality. This database can be an ideal instrument for improving the knowledge about this disease in our environment and to achieve better results. It would be desirable that this database could in the future be the origin of a national registry of spontaneous SAH

    Measurement of the production cross section of prompt J/ψ mesons in association with a W ± boson in pp collisions at √s = 7 TeV with the ATLAS detector

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    Aad, G. et al.The process pp → W ± J/ψ provides a powerful probe of the production mechanism of charmonium in hadronic collisions, and is also sensitive to multiple parton interactions in the colliding protons. Using the 2011 ATLAS dataset of 4.5 fb−1 of s√ = 7 TeV pp collisions at the LHC, the first observation is made of the production of W ± + prompt J/ψ events in hadronic collisions, using W ± → μν μ and J/ψ → μ + μ −. A yield of 27.4+7.5−6.5 W ± + prompt J/ψ events is observed, with a statistical significance of 5.1σ. The production rate as a ratio to the inclusive W ± boson production rate is measured, and the double parton scattering contribution to the cross section is estimated.We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWF and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT and NSRF, Greece; ISF, MINERVA, GIF, DIP and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT, Portugal; MNE/IFA, Romania; MES of Russia and ROSATOM, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MIZˇS, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Leverhulme Trust, United Kingdom; DOE and NSF, United States of America.Peer reviewe

    A search for an unexpected asymmetry in the production of e(+)mu(-) and e(-)mu(+) pairs in proton-proton collisions recorded by the ATLAS detector at root s=13 TeV

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    This search, a type not previously performed at ATLAS, uses a comparison of the production cross sections for e(+)mu(-) and e(-)mu(+) pairs to constrain physics processes beyond the Standard Model. It uses 139 fb(-1) of proton-proton collision data recorded at root s = 13 TeV at the LHC. Targeting sources of new physics which prefer final states containing e(+)mu(-) and e(-)mu(+), the search contains two broad signal regions which are used to provide model-independent constraints on the ratio of cross sections at the 2% level. The search also has two special selections targeting supersymmetric models and leptoquark signatures. Observations using one of these selections are able to exclude, at 95% confidence level, singly produced smuons with masses up to 640 GeV in a model in which the only other light sparticle is a neutralino when the R-parity-violating coupling lambda(23)(1)' is close to unity. Observations using the other selection exclude scalar leptoquarks with masses below 1880 GeV when g(1R)(eu) = g(1R)(mu c) = 1, at 95% confidence level. The limit on the coupling reduces to g(1R)(eu) = g(1R)(mu c) = 0.46 for a mass of 1420 GeV

    Dynamics of isolated-photon plus jet production in pp collisions at root s=7 TeV with the ATLAS detector

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    The dynamics of isolated-photon plus jet production in pp collisions at a centre-of-mass energy of 7 TeV has been studied with the ATLAS detector at the LHC using an integrated luminosity of 37 pb(-1). Measurements of isolated-photon plus jet bin-averaged cross sections are presented as functions of photon transverse energy, jet transverse momentum and jet rapidity. In addition, the bin-averaged cross sections as functions of the difference between the azimuthal angles of the photon and the jet, the photon jet invariant mass and the scattering angle in the photon jet centre-of-mass frame have been measured. Next-to-leading-order QCD calculations are compared to the measurements and provide a good description of the data, except for the case of the azimuthal opening angle

    Measurement of the cross-section for W boson production in association with b-jets in pp collisions at root s=7 TeV with the ATLAS detector

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    This paper reports a measurement of the W+b-jets (W+b+X and W+b (b) over bar +X) production cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV at the LHC. These results are based on data corresponding to an integrated luminosity of 4.6 fb(-1), collected with the ATLAS detector. Cross-sections are presented as a function of jet multiplicity and of the transverse momentum of the leading b-jet for both the muon and electron decay modes of the W boson. The W+b-jets cross-section, corrected for all known detector effects, is quoted in a limited kinematic range. Combining the muon and electron channels, the fiducial cross-section for W+b-jets is measured to be 7.1 +/- 0.5 (stat) +/- 1.4 (syst) pb, consistent with the next-to-leading order QCD prediction, corrected for non-perturbative and double-parton interactions (DPI) contributions, of 4.70 +/- 0.09 (stat) (+0.60)(-0.49) (scale) +/- 0.06 (PDF) +/- 0.16 (non-pert) (+0.52)(-0.38) (DPI) pb

    Triggers for displaced decays of long-lived neutral particles in the ATLAS detector

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    A set of three dedicated triggers designed to detect long-lived neutral particles decaying throughout the ATLAS detector to a pair of hadronic jets is described. The efficiencies of the triggers for selecting displaced decays as a function of the decay position are presented for simulated events. The effect of pile-up interactions on the trigger efficiencies and the dependence of the trigger rate on instantaneous luminosity during the 2012 data-taking period at the LHC are discussed
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