12,403 research outputs found
The Vector Curvaton
We analyze a massive vector field with a non-canonical kinetic term in the
action, minimally coupled to gravity, where the mass and kinetic function of
the vector field vary as functions of time during inflation. The vector field
is introduced following the same idea of a scalar curvaton, which must not
affect the inflationary dynamics since its energy density during inflation is
negligible compared to the total energy density in the Universe. Using this
hypothesis, the vector curvaton will be solely responsible for generating the
primordial curvature perturbation \zeta. We have found that the spectra of the
vector field perturbations are scale-invariant in superhorizon scales due to
the suitable choice of the time dependence of the kinetic function and the
effective mass during inflation. The preferred direction, generated by the
vector field, makes the spectrum of \zeta depend on the wavevector, i.e. there
exists statistical anisotropy in \zeta. This is discussed principally in the
case where the mass of the vector field increases with time during inflation,
where it is possible to find a heavy field (M >> H) at the end of inflation,
making the particle production be practically isotropic; thus, the longitudinal
and transverse spectra are nearly the same order which in turn causes that the
statistical anisotropy generated by the vector field is within the
observational bounds.Comment: LaTex file in Aipproc style, 6 pages, no figures. Prepared for the
conference proceedings of the IX Mexican School of the DGFM-SMF: Cosmology
for the XXIst Century. This work is entirely based on Refs. [23-26] and is
the result of Andres A. Navarro's MSc thesi
Effects of polylinker uATGs on the function of grass HKT1 transporters expressed in yeast cells
HvHKT1 mediates K+ or Na+ uniport in yeast cells if the expression promoter is joined directly to the HvHKT1 cDNA, and Na+-K+ symport if a 59-nt polylinker is inserted. Our results show that three ATG triplets in the polylinker decreased the synthesis of the transporter and that the lower amount of transporter caused the functional change. With the rice HKT1 cDNA, the 59-nt polylinker changed the mode of Na+ uptake from K+-insensitive to K+-inhibitable. These two modes of Na+ uptake also occurred in rice plant
DSUALMH-A new high-resolution dataset for NILM
[Abstract]: The optimisation of energy consumption requires a reasonably accurate measurement, so an appropriate and advanced monitoring system of the relevant electrical variables in the electrical installations is of paramount importance. In this context, interoperable and highly configurable devices play a crucial role. A clear example is the OpenZMeter (OZM) which is an open source, open hardware, multi-purpose precision smart meter that can measure a wide range of electrical variables at a high sampling rate and provide processed data on power quality. The aim of this work is to show the use and possible applications of the new high sampling frequency data provided by the OZM device, which are much richer and more accurate than those obtained with other low-cost electrical meters. For this purpose, the opensource tool NILMTK has been used and adapted. Likewise, the use of two of the best known and most widely used algorithms such as Combinatorial Optimisation (CO) and the Factorial Hidden Markov Model (FHMM) has been considered, analysing the results obtained in the experimental study and offering a detailed comparison of the performance of the two different disaggregation algorithms using metrics for the different cases, as well as the incorporation of transients, and the comparison with other public DatasetsMinisterio de Ciencia, Innovación y Universidades; PGC2018-098813-B-C33Universidad de Almería; UAL2020-TIC-A208
Connection of Isolated Stereoclusters by Combining C-13-RCSA, RDC, and J-Based Configurational Analyses and Structural Revision of a Tetraprenyltoluquinol Chromane Meroterpenoid from Sargassum muticum
The seaweed Sargassum muticum, collected on the southern coast of Galicia, yielded a tetraprenyltoluquinol chromane meroditerpene compound known as 1b, whose structure is revised. The relative configuration of 1b was determined by J-based configurational methodology combined with an iJ/DP4 statistical analysis and further confirmed by measuring two anisotropic properties: carbon residual chemical shift anisotropies (13C-RCSAs) and one-bond 1H-13C residual dipolar couplings (1DCH-RDCs). The absolute configuration of 1b was deduced by ECD/OR/TD-DFT methods and established as 3R,7S,11R
Association between the Use of Antibiotics and the Development of Acute Renal Injury in Patients Hospitalized for COVID-19 in a Hospital in the Peruvian Amazon
"Introduction: A significant antibiotic prescribing pattern associated with the COVID-19 pandemic has been described. Multiple protocols included empirical antimicrobials, leading to a substantial increase in antimicrobial consumption in medical care. A higher mortality rate is described among
patients diagnosed with COVID-19 who received antibiotics. Objectives: To determine the association
between the use of antibiotics and the development of acute renal injury in patients infected with
SARS-CoV-2 in patients treated at the Hospital II EsSalud de Ucayali, 2021. Methods: A cross-sectionalanalytical study was conducted, evaluating the medical records of patients admitted to the intensive
care unit between July 2020 and July 2021. For the statistical analysis, measures of central tendency
and dispersion, statistical hypothesis contrast tests were used in relation to acute kidney injury (AKI),
antibiotic use and associated factors, derived from linear regression models. Results: The factors that
were positively associated with the development of AKI were sepsis (aPR: 2.86; 95% CI: 1.26–6.43),
shock (aPR:2.49; 95% CI: 1.28–4.86), mechanical ventilation (aPR:9.11; 95% CI: 1.23–67.57), and use
of vancomycin (aPR: 3.15; 95% CI: 1.19–8.27). Conclusions: In the Peruvian Amazon, there is a high
consumption and inadequate prescription of antibiotics. The drugs most commonly used for the
treatment of COVID-19 were: aminoglycosides, vancomycin, ivermectin, azithromycin, tocilizumab,
and corticosteroids. The development of AKI among hospitalized patients was found to be related
to vancomycin administration. In addition, an association was found with the use of mechanical
ventilation, a high body mass index, and the presence of complications such as sepsis or shock.
Therefore, inappropriate antibiotic use for COVID-19 has been associated with multiple negative
outcomes and consequences.
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