1,880 research outputs found
Guía metodológica para la implementación de políticas de control de acceso utilizando la plataforma de Cisco Network Admission Control (CNAC) en la Universidad Autónoma de Bucaramanga – UNAB
The investigation below was made to show the importance of developing access control politics in organizations which are used to control the access of every single device that try to get a connection to company’s networks and by this way get the solution to protect their data, information and even their reputation. You will find security´s concepts on this document, access control and network´s control focusing on the own solution of cisco network assett collector as an emphasis to develop and design a proposal about a methodological guide to develop access control politics at Universidad Autonoma de Bucaramanga. This guide is divided into eight phases which let you know and understand the solutions for cisco. The technical requirements about software and hardware related and finally the general politics we must consider when setting CNAC.La presente investigación tiene como fin mostrar la importancia que tiene hoy en día la implementación de soluciones de control de acceso en las organizaciones las cuales son usadas con el fin de controlar de manera eficiente el acceso de cada uno de los dispositivos que intentan conectarse a las redes corporativas y de esta manera proteger sus datos y reputación. En este documento se mencionan conceptos de seguridad, control de acceso y control de acceso a redes, haciendo énfasis en la solución propietaria de Cisco la cual lleva por nombre Cisco Network Assett Collector y sobre la cual se diseñó una propuesta de implementación de una guía metodológica para la implementación de políticas de control de acceso en la Universidad Autónoma de Bucaramanga – UNAB. Esta guía está dividida en ocho fases, las cuales permiten conocer y comprender la solución de Cisco, los requerimientos técnicos en cuanto a software y hardware relacionados y finalmente las políticas generales que se deben considerar al momento de implementar CNAC
Methodological guide to develop Access control politics by using Cisco´s Network Admission Control platform at Universidad Autónoma de Bucaramanga
La presente investigación tiene como fin mostrar la importancia que tiene hoy en día la implementación de soluciones de control de acceso en las organizaciones las cuales son usadas con el fin de controlar de manera eficiente el acceso de cada uno de los dispositivos que intentan conectarse a las redes corporativas y de esta manera proteger sus datos y reputación. En este documento se mencionan conceptos de seguridad, control de acceso y control de acceso a redes, haciendo énfasis en la solución propietaria de Cisco la cual lleva por nombre Cisco Network Assett Collector y sobre la cual se diseñó una propuesta de implementación de una guía metodológica para la implementación de políticas de control de acceso en la Universidad Autónoma de Bucaramanga – UNAB. Esta guía está dividida en ocho fases, las cuales permiten conocer y comprender la solución de Cisco, los requerimientos técnicos en cuanto a software y hardware relacionados y finalmente las políticas generales que se deben considerar al momento de implementar CNAC.The investigation below was made to show the importance of developing access control politics in organizations which are used to control the access of every single device that try to get a connection to company’s networks and by this way get the solution to protect their data, information and even their reputation. You will find security´s concepts on this document, access control and network´s control focusing on the own solution of cisco network assett collector as an emphasis to develop and design a proposal about a methodological guide to develop access control politics at Universidad Autonoma de Bucaramanga. This guide is divided into eight phases which let you know and understand the solutions for cisco. The technical requirements about software and hardware related and finally the general politics we must consider when setting CNAC
Tomographic findings and mortality in patients with severe and critical pneumonia with COVID-19 diagnosis
Introduction: A high percentage of patients with non-severe (17.9%) and severe (2.9%) atypical pneumonia do not display pulmonary tomographic findings upon hospital admission; furthermore, lesion associated with COVI-19 are peripherally distributed in a multifocal ground-glass pattern, as well as displaying an irregular consolidation pattern, with a posterior or lower lobe predilection. The main objective of this study was to identify the pulmonary radiological patterns in patients diagnosed with SARS-CoV-2 pneumonia, the factors associated with the need for mechanical ventilation, as well as their survival rates at 30 days. Methods: We report the pulmonary tomographic findings of 490 consecutive patients with severe and critical pneumonia due to SARS-CoV-2. The patients were classified according to the tomography and demographic findings, sepsis severity prognostic scales, Charlson comorbidity index (CCI), the Sequential Organ Failure Assessment (SOFA), and the Acute Physiology and Chronic Health Evaluation (APACHE IV). The Kaplan-Meier method was used to calculate survival distributions. Results: 89.80% of patients had ground-glass opacities, 81.63% radiologic consolidation sign, 42.45% vascular thickening pattern, 37.55% lymphadenopathies, 14.90% pleural effusion, and 2.65% pulmonary thrombosis; meanwhile, 91.02% had bilateral lesions, 85.51% had peripheral lesions, and 75.92% had basal lobe lesions. APACHE IV (HR, 1.191, 95% CI [1.126, 1.260]), SOFA (HR, 5.178, 95%CI [3.103, 8.641]), and CCI (HR, 0.673, 95%CI [0.510, 0.889]), as well as the pulmonary damage severity index (HR, 1.282, 95%CI [1.151, 1.428]), predict the need for invasive mechanical ventilation. Only moderate ARDS patients with mild and severe lung disease showed different 30-day mortality distributions (χ2 = 7.00, p = 0.008). Discussion: Although the survival distributions did not vary significantly, an overwhelming majority of patients (i.e., 84.35%) with a higher pulmonary damage severity index (i.e., 23>) died within 30 days of hospital admission, while only 25.91% with moderate lung damage and 2.42% with mild lung damage
The decay in the presence of a constant antisymmetric tensor field
A constant antisymmetric 2-tensor can arise in general relativity with
spontaneous symmetry breaking or in field theories formulated in a
noncommutative space-time. In this work, the one-loop contribution of a
nonstandard vertex on the flavor violating quark transition is studied in the context of the electroweak Yang-Mills sector
extended with a Lorentz-violating constant 2-tensor. An exact analytical
expression for the on shell case is presented. It is found that the loop
amplitude is gauge independent, electromagnetic gauge invariant, and free of
ultraviolet divergences. The dipolar contribution to the
transition together with the experimental data on the decay is
used to derive the constraint TeV on the Lorentz-violating
scale.Comment: 14 pages and 2 figure
Inherently Safer Design and Optimization of Intensified Separation Processes for Furfural Production
Currently
furfural production has been the subject of increased
interest because it is a biobased chemical able to compete with fossil-based
chemicals. Furfural is characterized by flammability, explosion, and
toxicity properties. Improper handling and process design can lead
to catastrophic accidents. Hence it is of most importance to use inherent
safety concepts during the design stage. This work is the first to
present several new downstream separation processes for furfural purification,
which are designed using an optimization approach that simultaneously
considers safety criteria in addition to the total annual cost and
the eco-indicator 99. The proposed schemes include thermally coupled
configuration, thermodynamic equivalent configuration, dividing-wall
column, and a heat integrated configuration. These are compared with
the traditional separation process of furfural known as the Quaker
Oats Process. The results show that because of a large amount of water
present in the feed, similar values are obtained for total annual
cost and eco-indicator 99 in all cases. Moreover, the topology of
the processes has an important role in the safety criteria. The thermodynamic
equivalent configuration resulted as the safest alternative with a
40% reduction of the inherent risk with respect to the Quaker Oats
Process, and thus it is the safest option to purify furfural
Emerging properties of financial time series in the “Game of Life”
We explore the spatial complexity of Conway’s “Game of Life,” a prototypical cellular automaton by means of a geometrical procedure generating a two-dimensional random walk from a bidimensional lattice with periodical boundaries. The one-dimensional projection of this process is analyzed and it turns out that some of its statistical properties resemble the so-called stylized facts observed in financial time series. The scope and meaning of this result are discussed from the viewpoint of complex systems. In particular, we stress how the supposed peculiarities of financial time series are, often, overrated in their importance
High resolution spectroscopy of the high velocity hot post-AGB star LS III +52 24 (IRAS 22023+5249)
The first high-resolution (R~50,000) optical spectrum of the B-type star, LS
III +52 24, identified as the optical counterpart of the hot post-AGB candidate
IRAS 22023+5249 (I22023) is presented. We report the detailed identifications
of the observed absorption and emission features in the full wavelength range
(4290-9015 A) as well as the atmospheric parameters and photospheric abundances
(under the Local Thermodinamic Equilibrium approximation) for the first time.
The nebular parameters (Te, Ne) are also derived. We estimate Teff=24,000 K,
log g=3.0, xi=7 kms-1 and the derived abundances indicate a slightly
metal-deficient evolved star with C/O<1. The observed P-Cygni profiles of
hydrogen and helium clearly indicate on-going post-AGB mass loss. The presence
of [N II] and [S II] lines and the non-detection of [O III] indicate that
photoionisation has just started. The observed spectral features, large
heliocentric radial velocity, atmospheric parameters, and chemical composition
indicate that I22023 is an evolved post-AGB star belonging to the old disk
population. The derived nebular parameters (Te=7000 K, Ne=1.2x104 cm-3) also
suggest that I22023 may be evolving into a compact, young low-excitation
Planetary Nebula. Our optical spectroscopic analysis together with the recent
Spitzer detection of double-dust chemistry (the simultaneous presence of
carbonaceous molecules and amorphous silicates) in I22023 and other B-type
post-AGB candidates may point to a binary system with a dusty disk as the
stellar origin common to the hot post-AGB stars with O-rich central stars.Comment: Accepted for publication in MNRAS (22 pages, 4 figures, and 8
tables). arXiv admin note: substantial text overlap with arXiv:0707.059
Effect of Grazing Management on Herbage Accumulation of Lucerne-Orchard Grass Sward
Throughout most of México, lucerne (Medicago sativa) is the primary forage legume used in the dairy industry. Unfortunately, lucerne does not grow in late autumn and winter due to adverse weather. Recent studies with lucerne have suggested that the inclusion of a companion grass will invariably increase the seasonal distribution and total annual yield of swards (Laidlaw & Teuber, 2001). However the management of mixed swards containing lucerne is difficult as a grazing frequency or intensity which suits one species may be detrimental to the other. Changes in balance between grass and legume, especially in grazed swards, have been observed. In México mixtures of lucerne-orchard grass have a good persistence and productivity. However the explanation for this is unclear. This study examined the effects of different grazing management practices on lucerne-orchard grass production and seasonal distribution
Differential leukocyte expression of IFITM1 and IFITM3 in patients with severe pandemic influenza A(H1N1) and COVID-19
Interferon-induced transmembrane (IFITM) proteins mediate protection against enveloped viruses by blocking membrane fusion at endosomes. IFITM1 and IFITM3 are crucial for protection against influenza, and various single nucleotide polymorphisms altering their function have been linked to disease susceptibility. However, bulk IFITM1 and IFITM3 mRNA expression dynamics and their correlation with clinical outcomes have not been extensively addressed in patients with respiratory infections. In this study, we evaluated the expression of IFITM1 and IFITM3 in peripheral leukocytes from healthy controls and individuals with severe pandemic influenza A(H1N1) or coronavirus disease 2019 (COVID-19). Comparisons between participants grouped according to their clinical characteristics, underlying disease, and outcomes showed that the downregulation of IFITM1 was a distinctive characteristic of severe pandemic influenza A(H1N1) that correlated with outcomes, including mortality. Conversely, increased IFITM3 expression was a common feature of severe pandemic influenza A(H1N1) and COVID-19. Using a high-dose murine model of infection, we confirmed not only the downregulation of IFITM1 but also of IFITM3 in the lungs of mice with severe influenza, as opposed to humans. Analyses in the comparative cohort also indicate the possible participation of IFITM3 in COVID-19. Our results add to the evidence supporting a protective function of IFITM proteins against viral respiratory infections in humans.Introduction Methods - Human samples - IFITM expression in humans - Influenza infection in mice - IFITM expression in mice - Cytokine levels in mouse lungs - Study approval - Statistical analysis Results - Participant characteristics - IFITM1 and IFITM3 in patients with severe pandemic influenza A(H1N1) - High-dose influenza A (H1N1) virus infection downregulates IFITM expression in mice - IFITM1 and IFITM3 in severe COVID-19 Discussio
Phase-field model for Hele-Shaw flows with arbitrary viscosity contrast. II. Numerical study
We implement a phase-field simulation of the dynamics of two fluids with
arbitrary viscosity contrast in a rectangular Hele-Shaw cell. We demonstrate
the use of this technique in different situations including the linear regime,
the stationary Saffman-Taylor fingers and the multifinger competition dynamics,
for different viscosity contrasts. The method is quantitatively tested against
analytical predictions and other numerical results. A detailed analysis of
convergence to the sharp interface limit is performed for the linear dispersion
results. We show that the method may be a useful alternative to more
traditional methods.Comment: 13 pages in revtex, 5 PostScript figures. changes: 1 reference added,
figs. 4 and 5 rearrange
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