666 research outputs found
Intra-seasonal variability of extreme boreal stratospheric polar vortex events and their precursors
This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this record.The dynamical variability of the boreal stratospheric polar vortex has been usually analysed considering the
extended winter as a whole or only focusing on December, January and February. Yet recent studies have
found intra-seasonal differences in the boreal stratospheric dynamics. In this study, the intra-seasonal
variability of anomalous wave activity preceding polar vortex extremes in the Northern Hemisphere is
examined using ERA-Interim reanalysis data. Weak (WPV) and strong (SPV) polar vortex events are grouped
into early, mid- or late winter sub-periods depending on the onset date. Overall, the strongest (weakest) wave-
activity anomalies preceding polar vortex extremes are found in mid- (early) winter. Most of WPV
(SPV) events in early winter occur under the influence of east (west) phase of the Quasi-Biennial Oscillation
20 (QBO) and an enhancement (inhibition) of wavenumber-1 wave activity (WN1). Mid- and late winter WPV
21 events are preceded by a strong vortex and an enhancement of WN1 and WN2, but the spatial structure of the
anomalous wave activity and the phase of the QBO are different. Prior to mid-winter WPVs the enhancement
of WN2 is related to the predominance of La Niña and linked to blockings over Siberia. Mid-winter SPV
events show a negative phase of the Pacific-North America pattern that inhibits WN1 injected into the
stratosphere. This study suggests that dynamical features preceding extreme polar vortex events in mid-winter
should not be generalized to other winter sub-periods.This
work was supported by the Spanish Ministry of Economy and Competitiveness (grant number CGL2012-
34997). BA is supported by the Natural Environment Research Council (grant number NE/M006123/1). MA
acknowledges funding from the NASA ACMAP program
Geminivirus replication protein decreases PCNA sumoylation at two acceptor sites
Geminiviruses are plant viruses with circular, single-stranded DNA (ssDNA) genomes that infect a broad range of plants causing substantial crop diseases worldwide. They replicate in nuclei of infected cells by using host DNA replication machinery and an essential protein encoded in their genome designated Rep (replication-associated protein). This multifunctional protein induces the accumulation of the host factors involved in replication and it is capable of interacting with a lot of plant proteins including PCNA (Proliferating Cell Nuclear Antigen), a processivity factor that coordinates a wide range of processes involved in maintenance, duplication and transmission of the genome, and the sumoylation enzyme that conjugates SUMO to target proteins (SUMO-conjugating enzyme- SCE). PCNA modification by SUMO, and also ubiquitin, has long been known to be of key importance for determining how DNA damage is processed by the replisome and for maintenance of overall genome integrity. In yeast, PCNA sumoylation has been associated to DNA repair involving homologous recombination (HR). Previously, we reported that Rep ectopic expression does not result in broad changes in the sumoylation pattern of plant cells, but it modifies the sumoylation state of selected host proteins. In this work, we show, using a reconstituted sumoylation system in Escherichia coli, that tomato PCNA is sumoylated at two residues, K254 and K164, and that co-expression of the Rep protein suppresses PCNA sumoylation at these lysines. Finally, we confirm that PCNA is sumoylated and that Rep also interferes with PCNA sumoylation in planta.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
Mapping chemical structure-activity information of HAART-drug cocktails over complex networks of AIDS epidemiology and socioeconomic data of U.S. counties
[Abstract] Using computational algorithms to design tailored drug cocktails for highly active antiretroviral therapy (HAART) on specific populations is a goal of major importance for both pharmaceutical industry and public health policy institutions. New combinations of compounds need to be predicted in order to design HAART cocktails. On the one hand, there are the biomolecular factors related to the drugs in the cocktail (experimental measure, chemical structure, drug target, assay organisms, etc.); on the other hand, there are the socioeconomic factors of the specific population (income inequalities, employment levels, fiscal pressure, education, migration, population structure, etc.) to study the relationship between the socioeconomic status and the disease. In this context, machine learning algorithms, able to seek models for problems with multi-source data, have to be used. In this work, the first artificial neural network (ANN) model is proposed for the prediction of HAART cocktails, to halt AIDS on epidemic networks of U.S. counties using information indices that codify both biomolecular and several socioeconomic factors. The data was obtained from at least three major sources. The first dataset included assays of anti-HIV chemical compounds released to ChEMBL. The second dataset is the AIDSVu database of Emory University. AIDSVu compiled AIDS prevalence for >2300 U.S. counties. The third data set included socioeconomic data from the U.S. Census Bureau. Three scales or levels were employed to group the counties according to the location or population structure codes: state, rural urban continuum code (RUCC) and urban influence code (UIC). An analysis of >130,000 pairs (network links) was performed, corresponding to AIDS prevalence in 2310 counties in U.S. vs. drug cocktails made up of combinations of ChEMBL results for 21,582 unique drugs, 9 viral or human protein targets, 4856 protocols, and 10 possible experimental measures. The best model found with the original data was a linear neural network (LNN) with AUROC > 0.80 and accuracy, specificity, and sensitivity ≈ 77% in training and external validation series. The change of the spatial and population structure scale (State, UIC, or RUCC codes) does not affect the quality of the model. Unbalance was detected in all the models found comparing positive/negative cases and linear/non-linear model accuracy ratios. Using synthetic minority over-sampling technique (SMOTE), data pre-processing and machine-learning algorithms implemented into the WEKA software, more balanced models were found. In particular, a multilayer perceptron (MLP) with AUROC = 97.4% and precision, recall, and F-measure >90% was found
Programa de rehabilitación cardíaca mediante un entrenamiento de tenis adaptado
The aims of this study were to determine the effect of a cardiac rehabilitation program, based on the adjustment of a sports modality (tennis), on differentes laboratory analysis variables (triglycerides, cholesterol,cholesterol LDL, cholesterol HDL and glucose ) And and on an exercise stress test (metabolics equivalent-METs-, time of effort, systolic pressure, dyastolic pressure, maximum cardiac frecuencia and double product). The study involved 7 patients with low risk myocardial heart attack. The ages was include between 48 and 63 years old. By the end of the program, which has lasted 3 months, triglycerides, cholesterol, exercise capacity and double product had improved significantly (p<.005 for all).Los objetivos de este estudio son evaluar los efectos de nuestro programa de rehabilitación cardiaca, basado en la adaptación de una modalidad deportiva (tenis), sobre diferentes variables del perfil lipídico (triglicéridos, colesterol, cLDL, cHDL, y glucosa) así como en la prueba de esfuerzo (MET, tiempo de esfuerzo, presión sistólica, presión diastólica, frecuencia cardíaca máxima y doble producto). Analizamos a 7 pacientes con infarto agudo de miocardio de bajo riesgo. Las edades estaban comprendidas entre los 48 y 63 años. Tras la realización del programa, que ha tenido 3 meses de duración, se han producido mejoras significativas a nivel de triglicéridos, colesterol, capacidad funcional valorada en equivalentes metabólicos y doble producto (p<.005 para todos)
Observation and Spectroscopy of New Proton-Unbound Isotopes 30Ar and 29Cl: An Interplay of Prompt Two-Proton and Sequential Decay
Previously unknown isotopes Ar30 and Cl29 have been identified by measurement of the trajectories of their in-flight decay products S28+p+p and S28+p, respectively. The analysis of angular correlations of the fragments provided information on decay energies and the structure of the parent states. The ground states of Ar30 and Cl29 were found at 2.25+0.15−0.10 and 1.8±0.1 MeV above the two- and one-proton thresholds, respectively. The lowest states in Ar30 and Cl29 point to a violation of isobaric symmetry in the structure of these unbound nuclei. The two-proton decay has been identified in a transition region between simultaneous two-proton and sequential proton emissions from the Ar30 ground state, which is characterized by an interplay of three-body and two-body decay mechanisms. The first hint of a fine structure of the two-proton decay of Ar∗30(2+) has been obtained by detecting two decay branches into the ground and first-excited states of the S28 fragment.A. G., S. K., S. R., and P. S. were supported by the
Helmholtz Association Grant No. IK-RU-002. L. V. G.
was partly supported by the Ministry of Education and
Science of the Russian Federation Grant No. NSh-
932.2014.2. A. F., A. G., L. V. G., S. K., P. S., and R. S.
were partly supported by the Russian Foundation for
Basic Research Grant No. 14-02-00090-a. This work
was partly supported by the Polish National Science
Center under Contract No. UMO-2011/01/B/ST2/01943.
A. A. C. acknowledges support by the Polish Ministry of
Science and Higher Education by Grant No. 0079/DIA/
2014/43 (Grant Diamentowy). M. P. and X. X. are grateful
for a support from the Helmholtz International Center
for FAIR (HIC for FAIR). Y. L. was supported by the
Helmholtz-CAS Joint Research Group Grant No. HCJRG-
108. J. M. E. acknowledges support from the FPA2009-
08848 contract (MICINN, Spain
Three Realizations and Comparison of Hardware for Piezoresistive Tactile Sensors
Tactile sensors are basically arrays of force sensors that are intended to emulate the skin in applications such as assistive robotics. Local electronics are usually implemented to reduce errors and interference caused by long wires. Realizations based on standard microcontrollers, Programmable Systems on Chip (PSoCs) and Field Programmable Gate Arrays (FPGAs) have been proposed by the authors for the case of piezoresistive tactile sensors. The solution employing FPGAs is especially relevant since their performance is closer to that of Application Specific Integrated Circuits (ASICs) than that of the other devices. This paper presents an implementation of such an idea for a specific sensor. For the purpose of comparison, the circuitry based on the other devices is also made for the same sensor. This paper discusses the implementation issues, provides details regarding the design of the hardware based on the three devices and compares them
Nuevos datos sobre la distribución de pteronotus personatus (wagner, 1843) (chiroptera: mormoopidae) en colombia
La familia Momoopidae está integrada por los comúnmente denominados murciélagos bigotudos, de espalda desnuda y los de rostro de fantasma, que conforman en total dos géneros con ocho especies restringidas al Nuevo Mundo (GARDNER, 2007). Estos murciélagos tienen un amplio rango ecológico de tolerancia y ocupan hábitat que van desde muy calurosos, como bosques tropicales, hasta lugares áridos y secos. En Colombia se encuentran los dos géneros (Mormoops y Pteronotus), con cinco especies: Mormoops megalophylla (PETERS, 1864); Pteronotus davyi GRAY, 1838; P. gimnonotus NATTERER, 1843; P. parnellii (GRAY, 1843) y P. personatus (WAGNER, 1843), siendo abundantes especialmente en las costas de la región Caribe (MUÑOZ, 2001).Pteronotus personatus, se distribuye desde el Sur del desierto de Sonora en México hasta el Sur de la costa Atlántica en Mato Grosso, Brasil (DE LA TORRE y MEDELLÍN, 2010). En Colombia ha sido registrada en los departamentos de Antioquia, Bolívar, Cundinamarca y La Guajira (CUERVO et al., 1986; GARDNER, 2007). Esta especie vive generalmente por debajo de los 400 msnm, tolera los bosques secos, bosques multiestructurales verdes y bosques deciduos tropicales (MUÑOZ, 2001). Son de hábitos insectívoros, sin embargo, no hay datos publicados sobre aspectos específicos de la dieta, competencia y depredadores naturales (DE LA TORRE y MEDELLÍN, 2010)
\b{eta}-delayed three-proton decay of 31Ar
The beta decay of 31Ar, produced by fragmentation of a 36Ar beam at 880
MeV/nucleon, was investigated. Identified ions of 31Ar were stopped in a
gaseous time projection chamber with optical readout allowing to record decay
events with emission of protons. In addition to \b{eta}-delayed emission of one
and two protons we have clearly observed the beta-delayed three-proton branch.
The branching ratio for this channel in 31Ar is found to be 0.07(2)%.Comment: 5 pages, 3 figures, submitted to Physical Rev.
Terminal Crossbreeding of Murciano-Granadina Goats to Boer Bucks: Effects on Reproductive Performance of Goats and Growth of Kids in Artificial Rearing
The aim of this work was to improve the growth characteristics of Murciano-Granadina (MG) kids through terminal crossbreeding of MG goats to Boer bucks. Four experiments were carried out, using a total of 354 MG goats, half of which were mated with MG bucks (n = 12) and the other half with Boer bucks (n = 12). The kids were raised in artificial rearing until slaughter weight (9 kg). The birth weight and average daily gain were recorded in crossed kids (n = 197 and 145, respectively) and purebred kids (n = 257 and 169, respectively). Crossed kids presented significant differences (p < 0.001) compared to MG purebred kids in birth weight (+ 24%), mortality in artificial rearing (−37%), average daily gain (+32%) and milk powder conversion rate (−16%). However, the reproductive performance rates of MG goats mated with Boer bucks were slightly worse (pregnancy rate: 78.5% vs. 86.6%, p < 0.05; kidding rate: 62.0% vs. 75.7%; p < 0.01; prolificacy: 1.9 vs. 2.1 kids/parturition), especially when the matings took place in non-breeding season (experiments conducted at latitude 38–39° N). It is concluded that the terminal crossbreeding of MG goats to Boer bucks (those not used to produce replacement kids) could be an interesting option for ethical goat production
Do UK universities communicate their brands effectively through their websites?
This paper attempts to explore the effectiveness of UK universities’ websites. The area of branding in higher education has received increasing academic investigation, but little work has researched how universities demonstrate their brand promises through their websites. The quest to differentiate through branding can be challenging in the university context, however. It is argued that those institutions that have a strong distinctive image will be in a better position to face a changing future. Employing a multistage methodology, the web pages of twenty UK universities were investigated by using a combination of content and multivariable analysis. Results indicated ‘traditional values’ such as teaching and research were often well communicated in terms of online brand but ‘emotional values’ like social responsibility and the universities’ environments were less consistently communicated, despite their increased topicality. It is therefore suggested that emotional values may offer a basis for possible future online differentiation
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