8,810 research outputs found
Desarrollo para la comercialización y ventas nacionales e internacionales I CEDECOM "CTI TECHNICAL SERVICES"
El desarrollo de este proyecto surgió de la necesidad que se presenta en la empresa de generalizar el conocimiento que se debe de tener acerca de las implicaciones existentes en los procesos de importación que se deben llevar a cabo en México con el fin de agilizar los procesos logísticos de la empresa. Uno de los principales objetivos de este proyecto estuvo enfocado en encontrar la manera de plasmar el proceso de importación de mercancías y explicarlo de una forma lo más entendible y sencillo posible, esto con el fin de que cualquier persona (que tenga o no conocimientos previos acerca de este tema) pueda comprenderlo a su totalidad y le sea útil para tener una idea más amplia acerca de los trámites y procesos necesarios para lograr un correcto despacho aduanero en México. La manera en la que se logró explicar con mayor detalle este proceso, fue realizando un diagrama de flujo en el que se explican todos los procedimientos que se deben llevar a cabo con el fin de completar una importación al territorio mexicano; este diagrama fue hecho específicamente para la empresa, por lo que está adaptado a la forma en la que esta usualmente realiza sus importaciones, especificando paso a paso los procedimientos a realizarse, el encargado de cada procedimiento y los tiempos aproximados que se deben destinar para completar cada uno de los pasos a seguir. De igual manera, con el fin de lograr una adaptación lo más enfocada posible a este proyecto, se trabajó previamente en un análisis de información de distintos aspectos de la empresa, como lo son: situación actual de la empresa, principales productos importados sus especificaciones, rutas logísticas que se utilizan y la manera en la que actualmente llevan a cabo sus procesos aduanales en México.ITESO, A.C
Ingeniería molecular en "Triticum"
Se resumen las investigaciones realizadas sobre genética bioquímica de la especie aloploide de Triticum aestivum L. (trigo común). Dichas investigaciones abarcan los siguientes aspectos: a) localización cromosómica de genes que controlan sistemas moleculares; b) formas de interacción entre los genomios integrados en dicha especie; c) transferencia genética extraespecífica y extragenérica desde Aegilops ventricosa, Sécale cereale y Agropyron elongatum a trigo. Se especula sobre las implicaciones evolutivas de los resultados obtenidos y se enumeran las aplicaciones prácticas
Globules and pillars seen in the [CII] 158 micron line with SOFIA
Molecular globules and pillars are spectacular features, found only in the
interface region between a molecular cloud and an HII-region. Impacting
Far-ultraviolet (FUV) radiation creates photon dominated regions (PDRs) on
their surfaces that can be traced by typical cooling lines. With the GREAT
receiver onboard SOFIA we mapped and spectrally resolved the [CII] 158 micron
atomic fine-structure line and the highly excited 12CO J=11-10 molecular line
from three objects in Cygnus X (a pillar, a globule, and a strong IRAS source).
We focus here on the globule and compare our data with existing Spitzer data
and recent Herschel Open-Time PACS data. Extended [CII] emission and more
compact CO-emission was found in the globule. We ascribe this emission mainly
to an internal PDR, created by a possibly embedded star-cluster with at least
one early B-star. However, external PDR emission caused by the excitation by
the Cyg OB2 association cannot be fully excluded. The velocity-resolved [CII]
emission traces the emission of PDR surfaces, possible rotation of the globule,
and high-velocity outflowing gas. The globule shows a velocity shift of ~2 km/s
with respect to the expanding HII-region, which can be understood as the
residual turbulence of the molecular cloud from which the globule arose. This
scenario is compatible with recent numerical simulations that emphazise the
effect of turbulence. It is remarkable that an isolated globule shows these
strong dynamical features traced by the [CII]-line, but it demands more
observational studies to verify if there is indeed an embedded cluster of
B-stars.Comment: Letter accepted by A&A (SOFIA special issue
Towards a combined use of geophysics and remote sensing techniques for the characterization of a singular building: “El Torreón” (the tower) at Ulaca oppidum (Solosancho, Ávila, Spain)
This research focuses on the study of the ruins of a large building known as “El Torreón” (the Tower), belonging to the Ulaca oppidum (Solosancho, Province of Ávila, Spain). Different remote sensing and geophysical approaches have been used to fulfil this objective, providing a better understanding of the building’s functionality in this town, which belongs to the Late Iron Age (ca. 300–50 BCE). In this sense, the outer limits of the ruins have been identified using photogrammetry and convergent drone flights. An additional drone flight was conducted in the surrounding area to find additional data that could be used for more global interpretations. Magnetometry was used to analyze the underground bedrock structure and ground penetrating radar (GPR) was employed to evaluate the internal layout of the ruins. The combination of these digital methodologies (surface and underground) has provided a new perspective for the improved interpretation of “El Torreón” and its characteristics. Research of this type presents additional guidelines for better understanding of the role of this structure with regards to other buildings in the Ulaca oppidum. The results of these studies will additionally allow archaeologists to better plan future interventions while presenting new data that can be used for the interpretation of this archaeological complex on a larger scale
Optimizing dialysis dose in the context of frailty: an exploratory study
Introduction Frailty is a multicausal syndrome characterized by a decrease in strength, resistance and physiological function,
which makes the individual vulnerable and dependent, and increases his/her mortality. This syndrome is more prevalent
among older individuals, and chronic kidney disease patients, particularly those on dialysis. Dialysis dose is currently
standardized for hemodialysis (HD) patients regardless of their age and functional status. However, it has been postulated
that the dialysis dose required in older patients, especially frail ones, should be lower, since it could increase their degree
of frailty. Then, the purpose of this study was to evaluate if there would be a correlation between the dose of Kt/V and the
degree of frailty in a population of adult patients on HD.
Materials and methods A cross-sectional study with 82 patients on HD in Barranquilla (Colombia) and Lobos (Argentina)
was conducted. Socio-demographic and laboratory data, as well as dialysis doses (Kt/V) were recorded and scales of fragility,
physical activity, gait and grip strength were applied. Then these data were correlated by a Spearman’s correlation and
a logistic regression.
Results CFS, social isolation, physical activity, gait speed, and prehensile strength tests were outside the reference ranges
in the studied group. No significant correlation was found between dialysis dose and all the above mentioned functional
tests. However, a significant and inverse correlation between physical activity and CFS was documented (score − 1.41 (CI
− 2.1 to − 0.7).
Conclusion No significant correlation was documented between Kt/V value and different parameters of the frailty status, but
this status correlated significantly and inversely with physical activity in this group. Frailty status in hemodialysis patients
was significantly higher in older individuals, although young individuals were not exempt from it
Making Galaxies in a Cosmological Context: The Need for Early Stellar Feedback
We introduce the Making Galaxies in a Cosmological Context (MaGICC) program
of smoothed particle hydrodynamics (SPH) simulations. We describe a parameter
study of galaxy formation simulations of an L* galaxy that uses early stellar
feedback combined with supernova feedback to match the stellar mass--halo mass
relationship. While supernova feedback alone can reduce star formation enough
to match the stellar mass--halo mass relationship, the galaxy forms too many
stars before z=2 to match the evolution seen using abundance matching. Our
early stellar feedback is purely thermal and thus operates like a UV ionization
source as well as providing some additional pressure from the radiation of
massive, young stars. The early feedback heats gas to >10^6 K before cooling to
10^4 K. The pressure from this hot gas creates a more extended disk and
prevents more star formation prior to z=1 than supernovae feedback alone. The
resulting disk galaxy has a flat rotation curve, an exponential surface
brightness profile, and matches a wide range of disk scaling relationships. The
disk forms from the inside-out with an increasing exponential scale length as
the galaxy evolves. Overall, early stellar feedback helps to simulate galaxies
that match observational results at low and high redshifts.Comment: 13 pages, 14 figures, accepted MNRAS, movies at
http://www.mpia.de/~stinson/magic
Daily monitoring of TeV gamma-ray emission from Mrk 421, Mrk 501, and the Crab Nebula with HAWC
We present results from daily monitoring of gamma rays in the energy range
to TeV with the first 17 months of data from the High
Altitude Water Cherenkov (HAWC) Observatory. Its wide field of view of 2
steradians and duty cycle of % are unique features compared to other TeV
observatories that allow us to observe every source that transits over HAWC for
up to hours each sidereal day. This regular sampling yields
unprecedented light curves from unbiased measurements that are independent of
seasons or weather conditions. For the Crab Nebula as a reference source we
find no variability in the TeV band. Our main focus is the study of the TeV
blazars Markarian (Mrk) 421 and Mrk 501. A spectral fit for Mrk 421 yields a
power law index and
an exponential cut-off
TeV. For Mrk 501, we find an index and exponential cut-off TeV. The light curves for both sources show clear
variability and a Bayesian analysis is applied to identify changes between flux
states. The highest per-transit fluxes observed from Mrk 421 exceed the Crab
Nebula flux by a factor of approximately five. For Mrk 501, several transits
show fluxes in excess of three times the Crab Nebula flux. In a comparison to
lower energy gamma-ray and X-ray monitoring data with comparable sampling we
cannot identify clear counterparts for the most significant flaring features
observed by HAWC.Comment: 18 pages, 10 figures, accepted for publication in The Astrophysical
Journa
The 2HWC HAWC Observatory Gamma Ray Catalog
We present the first catalog of TeV gamma-ray sources realized with the
recently completed High Altitude Water Cherenkov Observatory (HAWC). It is the
most sensitive wide field-of-view TeV telescope currently in operation, with a
1-year survey sensitivity of ~5-10% of the flux of the Crab Nebula. With an
instantaneous field of view >1.5 sr and >90% duty cycle, it continuously
surveys and monitors the sky for gamma ray energies between hundreds GeV and
tens of TeV.
HAWC is located in Mexico at a latitude of 19 degree North and was completed
in March 2015. Here, we present the 2HWC catalog, which is the result of the
first source search realized with the complete HAWC detector. Realized with 507
days of data and represents the most sensitive TeV survey to date for such a
large fraction of the sky. A total of 39 sources were detected, with an
expected contamination of 0.5 due to background fluctuation. Out of these
sources, 16 are more than one degree away from any previously reported TeV
source. The source list, including the position measurement, spectrum
measurement, and uncertainties, is reported. Seven of the detected sources may
be associated with pulsar wind nebulae, two with supernova remnants, two with
blazars, and the remaining 23 have no firm identification yet.Comment: Submitted 2017/02/09 to the Astrophysical Journa
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