4,314 research outputs found
The continuous star formation history of a giant HII region in M101
We present results about the star formation process in the giant HII region
NGC 5471 in the outskirts of M101. From resolved HST/WPFC2 photometry we find
that star formation has been going for the last 70 Myr. We further compare
previous results from integrated infrared-optical photometry with the stellar
resolved CMD and we discuss the star formation properties of this region and
its individual knots, as well as characterizing the different stellar content.
This result has very important consequences in our understanding of the burst
versus continuous star formation activity in spiral galaxies.Comment: 2 pages, 2 figures. Proceeding of the conference From Stars to
Galaxies: Building the pieces to build up the Universe (Venice, Italy
Analysis of water-soluble vitamins in biopharma raw materials by electrophoresis micro-chips with contactless conductivity detection
Detailed information concerning the composition of the raw materials employed in the production
of biologics is important for the efficient control and optimization of bioprocesses. The analytical
methods used in these applications must be simple and fast as well as be easily transferable from
one site to another. In that context, microchip‐based electrophoresis represents a promising tool
for application in the analysis of raw materials in biologics. Using electrophoresis micro‐chips,
analysis times can be reduced to seconds and high separation efficiencies can be achieved using
extremely low volume samples, minimal reagent consumption and waste generation, low
cost/disposability, portability and ease of mass‐production [1].
Additionally the use of Capacitively Coupled Contactless Conductivity Detection (C4D) offers a
rather simple and yet sensitive method for detection of ionic species. Recently, C4D has gained
much popularity as on‐chip detection in electrophoresis micro‐chips [2]. The main reason for this
is that there is no physical contact of the detection electrodes with the electrolyte solution.
Therefore, the integration of this detection mode within the analytical system is rather simple.
Furthermore, the background noise is significantly reduced leading to lower detection limits than
the conventional contact conductivity detection.
Vitamins are present at very low concentrations in biopharma raw materials and are usually
determined using HPLC and CE methods [3]. Electrophoresis micro‐chips are a very good
alternative to these techniques due to the shorter analysis time and yet very good resolution,
among others.
In this paper, we present the application of electrophoresis micro‐chips with C4D detection to the
analysis of water‐soluble vitamins in raw materials used for the production of biologics in
bioreactors. For that purpose, hybrid PDMS/glass chips were fabricated by using standard
photolithographic techniques (Figure 1). The chip structure contains an extremely long channel of
101 mm (50 x 50 μm width x depth). Figure 2 shows the setup used for vitamins detection
Spectroscopic Observations of Planetary Nebulae in the Northern Spur of M31
We present spectroscopy of three planetary nebulae (PNe) in the Northern Spur
of the Andromeda Galaxy (M31) obtained with the Double Spectrograph on the 5.1
m Hale Telescope at the Palomar Observatory. The samples are selected from the
observations of Merrett et al. Our purpose is to investigate formation of the
substructures of M31 using PNe as a tracer of chemical abundances. The [O III]
4363 auroral line is detected in the spectra of two objects, enabling
temperature determinations. Ionic abundances are derived from the observed
collisionally excited lines, and elemental abundances of nitrogen, oxygen, and
neon as well as sulphur and argon are estimated. Correlations between oxygen
and the alpha-element abundance ratios are studied, using our sample and the
M31 disk and bulge PNe from the literature. In one of the three PNe, we
observed relatively higher oxygen abundance compared to the disk sample in M31
at similar galactocentric distances. The results of at least one of the three
Northern Spur PNe might be in line with the proposed possible origin of the
Northern Spur substructure of M31, i.e. the Northern Spur is connected to the
Southern Stream and both substructures comprise the tidal debris of the
satellite galaxies of M31.Comment: 5 tables, 17 figures; accepted for publication in Ap
Analysis of biopharma raw materials by electrophoresis microchips with contactless conductivity detection
Detailed information concerning the composition of the raw materials employed in the production of biologics is important for the efficient control and optimization of bioprocesses. We demonstrate the application of electrophoresis microchips with capacitively-coupled contactless conductivity detection (C4D) to the analysis of wa-ter-soluble vitamins and metal cations in raw material solutions that are subse-quently fed into bioreactors for the production of biologics
El petit amfiox: el miratge de l'origen dels vertebrats
L'origen dels vertebrats és un dels centres d'interès de molts científics i de la societat, i
el nostre animal favorit, el petit i amigable amfiox, fa més d'un segle que ocupa aquesta
posició privilegiada, i reflecteix en un miratge, com a fòssil vivent, el que va ocórrer en
aquell transcendental moment de l'evolució. No és només morfològicament el representant
viu de l'ancestre de tots els cordats, sinó que a més posseeix un genoma preduplicatiu,
un model en versió simple del genoma de tots els vertebrats, incloent-hi l'humà. L'anàlisi
del genoma de l'amfiox ha permès clarificar l'origen del nostre genoma propi,
alhora que l'ha situat en una posició clau per entendre l'origen i funcionament de famílies
i xarxes gèniques importants per al desenvolupament embrionari i la fisiologia. A més, els
avenços tècnics en la reproducció i experimentació permeten raonadament somiar a resoldre
els secrets dels nostres orígens i del funcionament del genoma.The little amphious: a mirage to the origen of vertebrates. The origin of vertebrates is one of the top interests for many scientists and the society, and our favorite animal has occupied this privileged position for more than a century, reflecting
in a mirage, as a living fossil, what occurred in this critical landmark of evolution.
It is not only morphologically the closest living relative of Chordates, but also possesses a
preduplicative genome, a simple model for the genome of all vertebrates, including humans.
The analysis of the amphioxus genome has served to clarify the origin of our own genome, and as showed it is in a key position to understand the origin and functioning of
gene families and gene networks critical for embryonic development and physiology. Besides,
technical advances in its reproduction and experimentation make plausible to
dream in illuminating the secrets of our origins and the functioning of the genome
Acoustic Rock Art Landscapes: A comparison between the Acoustics of three Levantine Rock Art areas in Mediterranean Spain
This article focuses on the relationship between acoustics and rock art in Levantine art in Mediterranean Spain. It takes as a case study three rock art areas where Levantine-style rock art was produced: the Valltorta Gorge, the Mortero Gorge and the Godall mountains. The study centres on the analysis of reverberation and echoes. In each area a comparison was made between the acoustic properties of sections of the area with rock art and of others with none. Different sounds were also tested in order to identify which possible instruments had the best chance of producing a sensory reaction. Although we cannot hypothesise on the specific practices that may have taken place in these areas, we conclude with the proposition that the acoustic properties of a site indicate a sacred use of the landscape, in which sound was a key element of ritual performance
Dinámicas y tendencias de la ganadería doble propósito en el sur del Estado de México
El sur del Estado de México, es zona ganadera y tiene el mayor inventario de bovinos en unidades de producción (UP) orientadas al doble propósito (DP). La información para este estudio se obtuvo de 78 UP seleccionadas mediante muestreo probalístico y se analizó de acuerdo a tres grupos: extensivo ( UPDPE ), tradicionalista ( UPDPT ) y semi-intensivo, ( UPDPSI ). El objetivo fue evaluar la dinámica, entendida como los cambios o innovaciones a través del tiempo (eva - luación ex-ante y ex-post), los objetivos y las opiniones de los ganaderos sobre el medio socioeconómico en el cual se desarrollan y la toma de decisiones en las UP, mediante Escala de Likert. Hubo cambios importantes en el aprovechamiento de la tierra y mayor tendencia al pastoreo, aumento del tamaño del hato, cuidado del ambiente e importancia de la toma de decisiones del ganadero. Resalta el manejo diferenciado de la ganadería, producto de las decisiones de los ganaderos sobre puntos estratégicos que determinan la capacidad de adaptación de las UP al medio socioeconómico en el cual se desarrollan
Situación actual de la ganadería de bovinos en el municipio de Tejupilco
La ganadería constituye una actividad importante en zonas rurales a pesar del acelerado crecimiento de actividades alternativas. El objetivo de este trabajo fue caracterizar unidades de producción (UP) de ganado bovino en el municipio de Tejupilco, Estado de México, desde un enfoque sistémico. Se recopiló información primaria mediante encuestas estructuradas y entrevista directa a 55 ganaderos. Las UP se agruparon en cuatro estratos en función del tamaño del hato (E1 = UP entre 1 y 10 unidades ganaderas totales; E2 = UP entre 11 y 21 UGT; E3 = UP entre 22 y 31 UGT; y E4 = UP con más de 32 UGT). La estructura de las UP, el manejo del ganado y la orientación de la producción depende del tamaño del hato y de la disponibilidad de tierra. UP de menor tamaño tienen mayor orientación a la producción de leche, mientras que UP grandes se orientan a la producción de becerros para abasto en un sistema extensivo, aunque también se observa la engorda de animales. Se destacó la diversidad de UP y se evidenció que hatos de menor tamaño aprovechan eficientemente la tierra, y UP de mayor tamaño hacen eficiente el uso de la mano de obraUNIVERSIDAD AUTÓNOMA DEL ESTADO DE MÉXICO CONSEJO NACIONAL DE CIENCIA Y TECNOLOGÍ
Chemical Abundances of Planetary Nebulae in the Substructures of M31
We present deep spectroscopy of planetary nebulae (PNe) that are associated
with the substructures of the Andromeda Galaxy (M31). The spectra were obtained
with the OSIRIS spectrograph on the 10.4 m GTC. Seven targets were selected for
the observations, three in the Northern Spur and four associated with the Giant
Stream. The most distant target in our sample, with a rectified galactocentric
distance >100 kpc, was the first PN discovered in the outer streams of M31. The
[O III] 4363 auroral line was well detected in the spectra of all targets,
enabling electron temperature determination. Ionic abundances are derived based
on the [O III] temperatures, and elemental abundances of helium, nitrogen,
oxygen, neon, sulfur, and argon are estimated. The relatively low N/O and He/H
ratios as well as abundance ratios of alpha-elements indicate that our target
PNe might belong to populations as old as ~2 Gyr. Our PN sample, including the
current seven and the previous three observed by Fang et al., have rather
homogeneous oxygen abundances. The study of abundances and the spatial and
kinematical properties of our sample leads to the tempting conclusion that
their progenitors might belong to the same stellar population, which hints at a
possibility that the Northern Spur and the Giant Stream have the same origin.
This may be explained by the stellar orbit proposed by Merrett et al. Judging
from the position and kinematics, we emphasize that M32 might be responsible
for the two substructures. Deep spectroscopy of PNe in M32 will help to assess
this hypothesis.Comment: Accepted for publication in the ApJ. 23 pages, including 13 figures
and 7 table
Implications for acetylsalicylic acid-sensitive pregnant women
Low-dose acetylsalicylic acid (ASA) is widely used during pregnancy to prevent obstetric complications of placental dysfunction, such as preeclampsia, stillbirth and fetal growth restriction, and obstetric complications in pregnant women with antiphospholipid syndrome. ASA-sensitive pregnant women cannot benefit from the effects of ASA due to the possibility of severe or potentially life-threatening hypersensitivity reactions to ASA. ASA desensitization is a valuable and safe therapeutic option for these women, allowing them to start daily prophylaxis with ASA and prevent pregnancy complications. The authors discuss the recent advances in obstetric conditions preventable by ASA and the management of ASA hypersensitivity in pregnancy, including ASA desensitization. To encourage the implementation of ASA desensitization protocols in ASA-sensitive pregnant women, they also propose a practical approach for use in daily clinical practice.publishersversionpublishe
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