5,294 research outputs found
Free energy and states of fractional-order hereditariness
Complex materials, often encountered in recent engineering and material sciences applications, show no complete separations between solid and fluid phases. This aspect is reflected in the continuous relaxation time spectra recorded in cyclic load tests. As a consequence the material free energy cannot be defined in a unique manner yielding a significative lack of knowledge of the maximum recoverable work that can extracted from the material. The non-uniqueness of the free energy function is removed in the paper for power-laws relaxation/creep function by using a recently proposed mechanical analogue to fractional-order hereditariness
Clinical Benefit of IVUS Guidance for Coronary Stenting: The ULTIMATE Step Toward Definitive Evidence?
Infall/Expansion Velocities in the Low-Mass Dense Cores L492, L694-2, and L1521F: Dependence on Position and Molecular Tracer
Although surveys of infall motions in dense cores have been carried out for
years, few surveys have focused on mapping infall across cores using multiple
spectral line observations. To fill this gap, we present IRAM 30-m Telescope
maps of N2H+(1-0), DCO+(2-1), DCO+(3-2), and HCO+(3-2) emission towards two
prestellar cores (L492 and L694-2) and one protostellar core (L1521F). We find
that the measured infall velocity varies with position across each core and
choice of molecular line, likely as a result of radial variations in core
chemistry and dynamics. Line-of-sight infall speeds estimated from DCO+(2-1)
line profiles can decrease by 40-50 m/s when observing at a radial offset >=
0.04 pc from the core's dust continuum emission peak. Median infall speeds
calculated from all observed positions across a core can also vary by as much
as 65 m/s depending on the transition. These results show that while
single-pointing, single-transition surveys of core infall velocities may be
good indicators of whether a core is either contracting or expanding, the
magnitude of the velocities they measure are significantly impacted by the
choice of molecular line, proximity to the core center, and core evolutionary
state.Comment: Accepted for publication in Ap
A rapid review of time management strategies among nurse managers
Background: Time management practice is the act of influencing one's behavioural dimensions to complete as many tasks as possible within a specified amount of time. These behavioural dimensions include work organization and the continued application of time management techniques. Good time management, such as setting goals and priorities, as well as planning and delegating tasks, can facilitate productivity and success, contributing to work effectiveness, maintaining balance and job satisfaction. Conversely, poor time management has been associated with poor quality of work, low productivity, negative influence on the career path, and high levels of stress. Aim: The study aims to identify the strategies used by middle nurse managers in time management. Methods: A rapid review of biomedical databases was undertaken during the month of June 2021. The included studies were published in English and in Italian. Results: Findings reveal that the most used and effective time management strategies for nurse managers are setting goals, and priorities and delegating tasks. Other useful strategies also found to be fundamental are discussed in detail. Conclusion: A manager should prioritize the concept of planning, which can be counted as an efficient time management technique and educate himself on delegating. Time management has an impact not only on productivity and organizational success, but also on the balance between private and working life of managers
Biochemical data from the characterization of a new pathogenic mutation of human pyridoxine-5'-phosphate oxidase (PNPO)
PNPO deficiency is responsible of severe neonatal encephalopathy, responsive to pyridoxal-5’-phosphate (PLP) or pyridoxine. Recent studies widened the phenotype of this condition and detected new genetic variants on PNPO gene, whose pathogenetic role and clinical expression remain to be established. One of these mutations, Arg116Gln, is of particular interest because of its later onset of symptoms (beyond the first months of life) and its peculiar epileptic manifestations in patients. This protein variant was expressed as recombinant protein in E coli, purified to homogeneity, and characterized with respect to structural and kinetic properties, stability, binding constants of cofactor flavin mononucleotide (FMN) and product (PLP) in order to define the molecular and structural bases of its pathogenicity.
For interpretation and discussion of reported data, together with the description of clinical studies, refer to the article [7][1] (doi: 10.1016/j.ymgme.2017.08.003)
A yeast synthetic network for in-vivo assessment of reverse engineering and modelling.
Systems biology approaches are extensively used to model and reverse engineer gene regulatory networks from experimental data. Conversely, synthetic biology allows ‘‘de novo’’ construction of a regulatory network to seed new functions in the cell. At present, the usefulness and predictive ability of modeling and reverse engineering cannot be assessed and compared rigorously. We built in the yeast Saccharomyces cerevisiae a synthetic network, IRMA, for in vivo ‘‘benchmarking’’ of reverse-engineering and modeling approaches. The network is composed of five genes regulating each other through a variety of regulatory interactions; it is negligibly affected by endogenous genes, and it is responsive to small molecules. We measured time series and steady-state expression data after multiple perturbations. These data were used to assess state-of-the-art modeling and reverse-engi- neering techniques. A semiquantitative model was able to capture and predict the behavior of the network. Reverse engineering based on differential equations and Bayesian networks correctly inferred regulatory interactions from the experimental data
The COMPLETE Survey of Star-Forming Regions: Phase I Data
We present an overview of data available for the Ophiuchus and Perseus
molecular clouds from ``Phase I'' of the COMPLETE Survey of Star-Forming
Regions. This survey provides a range of data complementary to the Spitzer
Legacy Program ``From Molecular Cores to Planet Forming Disks.'' Phase I
includes: Extinction maps derived from 2MASS near-infrared data using the NICER
algorithm; extinction and temperature maps derived from IRAS 60 and 100um
emission; HI maps of atomic gas; 12CO and 13CO maps of molecular gas; and
submillimetre continuum images of emission from dust in dense cores. Not
unexpectedly, the morphology of the regions appears quite different depending
on the column-density tracer which is used, with IRAS tracing mainly warmer
dust and CO being biased by chemical, excitation and optical depth effects.
Histograms of column-density distribution are presented, showing that
extinction as derived from 2MASS/NICER gives the closest match to a log-normal
distribution as is predicted by numerical simulations. All the data presented
in this paper, and links to more detailed publications on their implications
are publically available at the COMPLETE website.Comment: Accepted by AJ. Full resolution version available from:
http://www.cfa.harvard.edu/COMPLETE/papers/complete_phase1.pd
Effects of crystal morphology on the hot-carrier dynamics in mixed-cation hybrid lead halide perovskites
Ultrafast pump-probe spectroscopies have proved to be an important tool for the investigation of charge carriers dynamics in perovskite materials providing crucial information on the dynamics of the excited carriers, and fundamental in the development of new devices with tailored photovoltaic properties. Fast transient absorbance spectroscopy on mixed-cation hybrid lead halide perovskite samples was used to investigate how the dimensions and the morphology of the perovskite crystals embedded in the capping (large crystals) and mesoporous (small crystals) layers affect the hot-carrier dynamics in the first hundreds of femtoseconds as a function of the excitation energy. The comparative study between samples with perovskite deposited on substrates with and without the mesoporous layer has shown how the small crystals preserve the temperature of the carriers for a longer period after the excitation than the large crystals. This study showed how the high sensitivity of the time-resolved spectroscopies in discriminating the transient response due to the different morphology of the crystals embedded in the layers of the same sample can be applied in the general characterization of materials to be used in solar cell devices and large area modules, providing further and valuable information for the optimization and enhancement of stability and efficiency in the power conversion of new perovskite-based devices
Cardiogenic Shock in Obstructive Hypertrophic Cardiomyopathy Plus Apical Ballooning: Management With VA-ECMO and Myectomy
A patient with known obstructive hypertrophic cardiomyopathy developed worsening left ventricular outflow tract obstruction, severe mitral regurgitation, and apical ballooning leading to cardiogenic shock, a combination in which treatment of each component could worsen the others. Emergency veno-arterial extracorporeal membrane oxygenation, levosimendan, and noradrenaline transiently restored adequate systemic perfusion and gas exchange. Surgical myectomy offered a more definitive solution. (Level of Difficulty: Intermediate.
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