1,144 research outputs found
Identification of novel bioactive peptides
Motivation: Targeting agents are the most commonly used strategies in therapeutics and diagnostic treatment.They can be classified in two main classes: chemicals and biologicals. Chemicals (farmaceutics and related) have been used for years, but nowadays biologicals experience an increasing demand because of their potentially higher specificity and affinity. Bioactive peptides from rational design can act as targeting agents that specifically interact with, and mostly inhibit, a biomolecule of interest (Seignauric et al., 2011).Methods: We have built a large library of peptides, and are screening for those that have biological activity, specially related to cell proliferation inhibition. The initial inconvenience is that small peptides cannot be expressed from single transcription unit as larger proteins, as they will be destroyed by cell proteases system. It is necessary to include the peptide library into a protein scaffold. We have designed a novel structure that includes the variable peptide sequence from the library between two mini-domains "EFLIVIKS" (one letter aminoacid code) able to form a noncovalent loop (Gururaja et al., 2010). In one of our constructs we have included a T7 promoter to allow conditional expression in bacteria. For its expression, we have designed two large nucleotide sequences (79 and 124 nucleotides, the large one includes the variable peptide sequence) that assemble by 20 complementary nucleotides in their 3' ends. By polymerization, both oligos strings are filled and form a two-chain structure, that will be inserted in a expression vector to obtain our peptide library. We transform bacteria (E. coli) and yeast (Schizosaccharomyces pombe) in order to identify those colonies excpressing the bioactive peptides that kill the cells or interrupt cell cycle
Secondary homotopy groups
Secondary homotopy groups supplement the structure of classical homotopy
groups. They yield a track functor on the track category of pointed spaces
compatible with fiber sequences, suspensions and loop spaces. They also yield
algebraic models of homotopy types with homotopy groups concentrated in two
consecutive dimensions.Comment: We added further commets and references to make the paper more easily
readabl
The Second INTEGRAL AGN Catalogue
The INTEGRAL mission provides a large data set for studying the hard X-ray
properties of AGN and allows testing of the unified scheme for AGN. We present
analysis of INTEGRAL IBIS/ISGRI, JEM-X, and OMC data for 199 AGN supposedly
detected by INTEGRAL above 20 keV. The data analysed here allow a significant
spectral extraction on 148 objects and an optical variability study of 57 AGN.
The slopes of the hard X-ray spectra of Seyfert 1 and Seyfert~2 galaxies are
found to be consistent within the uncertainties, whereas higher cut-off
energies and lower luminosities are measured for the more absorbed / type 2
AGN. The intermediate Seyfert 1.5 objects exhibit hard X-ray spectra consistent
with those of Seyfert 1. When applying a Compton reflection model, the
underlying continua appear the same in Seyfert 1 and 2 with photon index 2, and
the reflection strength is about R = 1, when assuming different inclination
angles. A significant correlation is found between the hard X-ray and optical
luminosity and the mass of the central black hole in the sense that the more
luminous objects appear to be more massive. There is also a general trend
toward the absorbed sources and type 2 AGN having lower Eddington ratios. The
black holemass appears to form a fundamental plane together with the optical
and X-ray luminosity of the form Lv being proportional to Lx^0.6 M^0.2, similar
to that found between radio luminosity Lr, Lx, and M. The unified model for
Seyfert galaxies seems to hold, showing in hard X-rays that the central engine
is the same in Seyfert 1 and 2, but seen under different inclination angles and
absorption. (Abridged)Comment: 26 pages, 16 figures, accepted for publication in A&A. Corrections by
language editor included in version
Rapid spectral transition of the black hole binary V404 Cyg
During the June 2015 outburst of the black hole binary V404 Cyg, rapid
changes in the X-ray brightness and spectra were common. The INTEGRAL
monitoring campaign detected spectacular Eddington-limited X-ray flares, but
also rapid variations at much lower flux levels. On 2015 June 21 at 20 h 50
min, the 3-10 keV JEM-X data as well as simultaneous optical data started to
display a gradual brightening from one of these low-flux states. This was
followed 15 min later by an order-of-magnitude increase of flux in the 20-40
keV IBIS/ISGRI light curve in just 15 s. The best-fitting model for both the
pre- and post-transition spectra required a Compton-thick partially covering
absorber. The absorber parameters remained constant, but the spectral slope
varied significantly during the event, with the photon index decreasing from
to . We propose that the rapid 20-40
keV flux increase was either caused by a spectral state transition that was
hidden from our direct view, or that there was a sudden reduction in the amount
of Compton down-scattering of the primary X-ray emission in the disk outflow.Comment: 6 pages, 2 figures, accepted to A&
Street lighting energy efficiency
Un estudio sobre la optimización de la eficiencia energética en el alumbrado público de la Municipalidad de S. M. de Tucumán fue efectuado basado en la aplicación de relojes astronómicos, balastos electrónicos dimerizables para lámparas de descarga de Sodio de alta presión de 150W/100W y luminarias de alta eficiencia. Durante 45 días, 273 puntos de luz conectados a 6 redes de alumbrado independientes fueron monitoreados, registrando el consumo, tiempos de funcionamiento, apagados nocturnos, encendidos diurnos y parámetros eléctricos de calidad. Los resultados indican que es posible una importante reducción en el consumo, entre un 11% y un 43% mejorando la calidad del servicio y reduciendo el contenido de armónicos que se introducen a la red de alumbrado a TDH A ≤ 6,5%. El trabajo describe la experiencia y el análisis de los resultados obtenidos.A study of street lighting energy efficiency was carried out in S. M. Tucumán City, based on the application of astronomical clocks, electronic ballasts (control gear) for high pressure sodium 150W/100W lamps and high efficiency luminaires. During 45 days, 273 luminaires connected to 6 independent electric networks were monitored recording: energy consumption, switching on/off times, night lamps outages, day on lamps and electrical quality parameters. The results indicate that it is possible a significant reduction in consumption, between 11% and 43% while improving service quality and reducing the harmonic content being introduced to the network lighting by TDH A ≤ 6.5%. The paper describes the experience and the analysis of the results.Fil: Tapia Garzón J.. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Luminotecnia, Luz y Visión; ArgentinaFil: Manzano, Eduardo Roberto. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Luminotecnia, Luz y Visión; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; ArgentinaFil: Gao S.. Municipalidad de S. M. Tucuman - Dirección Alumbrado; ArgentinaFil: Rojas M.. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Luminotecnia, Luz y Visión; ArgentinaFil: De Nobrega M.. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Luminotecnia, Luz y Visión; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; Argentin
Assessment of Peak Water Usage among Residential Consumers across Several Drinking Water Service Areas
[EN] Public drinking water service providers must comprehensively understand and effectively characterise user demands, especially during peak hours, which not only impact the maximum demand within the distribution network but also determine the dimensions of interior networks within buildings. Residential consumers show different consumption patterns based on socioeconomic factors, spatial location, climatic conditions and the consistency and quality of service delivered by public service providers. This study focused on assessing 1,317,584 users distributed across four distinct service areas in Bogota, Colombia. To achieve this, a stratified random sampling of 1233 residential subscribers was conducted and 320 reference digital Y290 Aquabus micro-meters were installed to characterise the four service areas. The installations were grouped into sets of 320 users until the entire sample of 1233 subscribers was encompassed. The results demonstrated that the rational method provided the most accurate fit for estimating the probable maximum flow rates compared to the values measured and, consequently, is the most suitable method for application within the region of interest. However, whereas the Hunter Unal method displayed a reasonable fit, it tended to underestimate the size of internal networks within buildings. The remaining methods, such as the British, square root, simultaneity, Hunter, NTC 1500 Hunter and Chilean methods, did not yield significant adjustments and tended to overestimate the probable maximum flow rates as well as the internal networks within buildings. The results indicate that, depending on the method used to calculate the probable maximum flow or design flow of the internal network, there can be a deviation factor when compared to the actual peak flow measured (real maximum flow). This deviation factor ranges from 0.79 (calculated less than measured) to 3.77 (calculated greater than measured). Additionally, a sizing case study was conducted, which involved applying all methods to a scenario involving a residential user. This study aimed to determine the variation expected in the estimation of the diameter of the supply pipe to the internal network when using the flow results from different methods. This analysis serves to conclude the research.Garzón-Orduña, AJ.; Coronado-Hernández, OE.; Ortiz, RO.; Arrieta-Pastrana, A.; Fuertes-Miquel, VS. (2024). Assessment of Peak Water Usage among Residential Consumers across Several Drinking Water Service Areas. Sustainability. 16(4):1-31. https://doi.org/10.3390/su1604160113116
Inhomogeneity correction of magnetic resonance images by minimization of intensity overlapping
Proceeding of: IEEE 2003 International Conference on Image Processing (ICIP), Barcelona, Spain, 14-17 Sept. 2003This work presents a new algorithm (NIC; Non uniform Intensity Correclion) for the correction of intensity inhomogeneities in magnetic resonance images. The algorithm has been validated by means of realistic phantom images and a set of 24 real images. Evaluation using previously proposed phantom images for inhomogeneity correction algorithms allowed us to obtain results fully comparable to the previous literature on the topic. This new algorithm was also compared, using a real image dataset, to other widely used methods which are
freely available in the Internet (N3, SPM'99 and SPM2).
Standard quality criteria have been used for determining the goodness of the different methods. The new algorithm showed better results removing the intensity inhomogeneities and did not produce degradation when used on images free from this artifact
A major star formation region in the receding tip of the stellar Galactic bar
We present an analysis of the optical spectroscopy of 58 stars in the
Galactic plane at \arcdeg, where a prominent excess in the flux
distribution and star counts have been observed in several spectral regions, in
particular in the Two Micron Galactic Survey (TMGS) catalog. The sources were
selected from the TMGS, to have a magnitude brighter than +5 mag and be
within 2 degrees of the Galactic plane. More than 60% of the spectra correspond
to stars of luminosity class I, and a significant proportion of the remainder
are very late giants which would also be fast evolving. This very high
concentration of young sources points to the existence of a major star
formation region in the Galactic plane, located just inside the assumed origin
of the Scutum spiral arm. Such regions can form due to the concentrations of
shocked gas where a galactic bar meets a spiral arm, as is observed at the ends
of the bars of face-on external galaxies. Thus, the presence of a massive star
formation region is very strong supporting evidence for the presence of a bar
in our Galaxy.Comment: 13 pages (latex) + 4 figures (eps), accepted in ApJ Let
Long-term optical and X-ray variability of the Be/X-ray binary H 1145-619: Discovery of an ongoing retrograde density wave
Context. Multiwavelength monitoring of Be/X-ray binaries is crucial to understand the mechanisms producing their outbursts. H 1145-619 is one of these systems, which has recently displayed X-ray activity
Syngenta Enogen Feed Corn Containing an Alpha Amylase Expression Trait Improves Digestibility in Growing Calf Diets
Objective: To evaluate the digestibility parameters of growing cattle when fed Enogen Feed corn.
Study Description: Seven cannulated Holstein steers were used to determine the effects on digestibility when fed Enogen Feed corn (Syngenta) as whole-corn or processed as dry-rolled at ad libitum intake.
The Bottom Line: When Enogen Feed corn was fed in an ad libitum fashion to growing calves, dry matter and organic matter are digested to a greater extent relative to yellow corn
- …