185 research outputs found
Water in Lope de Vega’s literary image of Madrid
El presente trabajo es parte de una tesis doctoral en curso sobre la ciudad en Lope de Vega del programa de doctorado en Historia e Historia del Arte y Territorio de la Universidad Nacional de Educación a DistanciaLope de Vega recreó en su obra muchas escenas en las que el agua era un elemento indispensable en la construcción de la imagen literaria de Madrid. El poeta recurre a lo beneficioso de las aguas, río o fuentes, como argumento de grandeza de la ciudad dentro de la norma corográfica de la época. En su poética, por tanto, subyace el ideal de modelo urbano clásico aplicado a una villa que aspiraba a ser asiento estable de la Corte. Además, con la introducción de estos topoi historiográficos, contribuyó en la difusión de las laudes de Madrid a través del teatroIn his work, Lope de Vega recreated scenes in which water becomes an indispensable element in the construction of Madrid’s literary image. He uses the benefits of water, rivers and fountains as argument in defense of the town within the chorographic standard of the Modern Age. The underlying theme of his poetry is thus the classic urban idyllic model applied to a town that aspired to be the steady seat of the Court. With the introduction of these historiographic topoi, Lope de Vega contributed to the spread of the laudes of Madrid through theatr
Aproximación al estudio de las vistas urbanas de ciudades españolas en el teatro de Lope de Vega: las vistas de Valencia y Toledo
A través del análisis de la representación de la ciudad en algunas obras de Lope de Vega se pueden distinguir dos técnicas: la «representación metonímica» en la que un atributo o parte define toda la urbe, y las “vistas urbanas” en las que diferentes elementos de la ciudad restituyen un mapa mental de la misma. Mediante el estudio comparado de estas corografías lopescas con las historias de ciudades, crónicas y vistas urbanas hemos podido identificar características comunes que subyacen a una cultura visual que regía la contemplación y la representación la ciudad. La iconografía urbana en Lope es heredera de la tradición de las laudes civitatum, por un lado; y por otro, de la cartografía urbana con la que comparten el mismo punto de vista. Todo ello debe contextualizarse en la vocación de cronista que tuvo siempre Lope
A surgical model of short bowel syndrome induces a long-lasting increase in pancreatic beta-cell mass
Several surgical techniques are used nowadays as a severe treatment for obesity and diabetes mellitus type 2. These techniques are aggressive due to drastic changes in the nutrient flow and non-reversible modifications on the digestive tube. In this paper we present the effects of a massive intestinal resection on the pancreas. Results have shown that short bowel technique is less aggressive to normal anatomy and physiology of the intestinal tract than Gastric bypass or biliopancreatic diversion (e.g.). In this paper we reproduce a model of short bowel syndrome (SIC), with similar surgical conditions and clinical complications as seen in human cases. This work was conducted on normal Wistar rats, with no other concurrent factors, in order to determine the effects on normal pancreas islets.
We measured pancreatic implications by histomorphometric studies, which included beta-cell mass by immunocytochemistry, and apoptosis/proliferation test with TUNEL technique and Ki-67. Briefly, we reported on an increased relative area of the islets of the pancreas, as well as an increase in the average size of islets in the
SIC versus the control group. Furthermore we stated that this increase in size of the pancreatic islets is due to the
mechanisms of proliferation of beta cells in animals undergoing SIC. These goals could reveal a direct
influence of surgical modification of the digestive tract over the pancreatic beta cell homeostasis. In this sense,
there are many potential stimulators of intestinal adaptation, including peptide hormones and growth
components which are associated or involved as effectors of the endocrine pancreas
Dynamical Confirmation of SDSS Weak Lensing Scaling Laws
Galaxy masses can be estimated by a variety of methods; each applicable in
different circumstances, and each suffering from different systematic
uncertainties. Confirmation of results obtained by one technique with analysis
by another is particularly important. Recent SDSS weak lensing measurements of
the projected-mass correlation function reveal a linear relation between galaxy
luminosities and the depth of their dark matter halos (measured on 260 \hinv
kpc scales). In this work we use an entirely independent dynamical method to
confirm these results. We begin by assembling a sample of 618 relatively
isolated host galaxies, surrounded by a total of 1225 substantially fainter
satellites. We observe the mean dynamical effect of these hosts on the motions
of their satellites by assembling velocity difference histograms. Dividing the
sample by host properties, we find significant variations in satellite velocity
dispersion with host luminosity. We quantify these variations using a simple
dynamical model, measuring \mtsd a dynamical mass within 260 \hinv kpc. The
appropriateness of this mass reconstruction is checked by conducting a similar
analysis within an N-body simulation. Comparison between the dynamical and
lensing mass-to-light scalings shows reasonable agreement, providing some
quantitative confirmation for the lensing results.Comment: 7 pages, 3 figures, accepted for publication in ApJ Letter
State-of-the-art and novel approaches to mild solubilization of inclusion bodies
Throughout the twenty-first century, the view on inclusion bodies (IBs) has shifted from undesired by-products towards a targeted production strategy for recombinant proteins. Inclusion bodies can easily be separated from the crude extract after cell lysis and contain the product in high purity. However, additional solubilization and refolding steps are required in the processing of IBs to recover the native protein. These unit operations remain a highly empirical field of research in which processes are developed on a case-by-case basis using elaborate screening strategies. It has been shown that a reduction in denaturant concentration during protein solubilization can increase the subsequent refolding yield due to the preservation of correctly folded protein structures. Therefore, many novel solubilization techniques have been developed in the pursuit of mild solubilization conditions that avoid total protein denaturation. In this respect, ionic liquids have been investigated as promising agents, being able to solubilize amyloid-like aggregates and stabilize correctly folded protein structures at the same time. This review briefly summarizes the state-of-the-art of mild solubilization of IBs and highlights some challenges that prevent these novel techniques from being yet adopted in industry. We suggest mechanistic models based on the thermodynamics of protein unfolding with the aid of molecular dynamics simulations as a possible approach to solve these challenges in the future
Corrigendum: State-of-the-art and novel approaches to mild solubilization of inclusion bodies
Dark Matter and Stellar Mass in the Luminous Regions of Disk Galaxies
We investigate the correlations among stellar mass (M_*), disk scale length
(R_d), and rotation velocity at 2.2 disk scale lengths (V_2.2) for a sample of
81 disk-dominated galaxies (disk/total >= 0.9) selected from the SDSS. We
measure V_2.2 from long-slit H-alpha rotation curves and infer M_* from galaxy
i-band luminosities (L_i) and g-r colors. We find logarithmic slopes of
2.60+/-0.13 and 3.05+/-0.12 for the L_i-V_2.2 and M_*-V_2.2 relations, somewhat
shallower than most previous studies, with intrinsic scatter of 0.13 dex and
0.16 dex. Our direct estimates of the total-to-stellar mass ratio within
2.2R_d, assuming a Kroupa IMF, yield a median ratio of 2.4 for M_*>10^10 Msun
and 4.4 for M_*=10^9-10^10 Msun, with large scatter at a given M_* and R_d. The
typical ratio of the rotation speed predicted for the stellar disk alone to the
observed rotation speed at 2.2R_d is ~0.65. The distribution of R_d at fixed
M_* is broad, but we find no correlation between disk size and the residual
from the M_*-V_2.2 relation, implying that this relation is an approximately
edge-on view of the disk galaxy fundamental plane. Independent of the assumed
IMF, this result implies that stellar disks do not, on average, dominate the
mass within 2.2R_d. We discuss our results in the context of infall models of
disk formation in cold dark matter halos. A model with a disk-to-halo mass
ratio m_d=0.05 provides a reasonable match to the R_d-M_* distribution for spin
parameters \lambda ranging from ~0.04-0.08, and it yields a reasonable match to
the mean M_*-V_2.2 relation. A model with m_d=0.1 predicts overly strong
correlations between disk size and M_*-V_2.2 residual. Explaining the wide
range of halo-to-disk mass ratios within 2.2R_d requires significant scatter in
m_d values, with systematically lower m_d for galaxies with lower .Comment: 18 pages, 2 tables, 7 figures, Accepted to ApJ, Table 1 updated,
otherwise minor change
Low-Surface-Brightness Galaxies in the Sloan Digital Sky Survey. I. Search Method and Test Sample
In this paper we present results of a pilot study to use imaging data from
the Sloan Digital Sky Survey (SDSS) to search for low-surface-brightness (LSB)
galaxies. For our pilot study we use a test sample of 92 galaxies from the
catalog of Impey et al. (1996) distributed over 93 SDSS fields of the Early
Data Release (EDR). Many galaxies from the test sample are either LSB or dwarf
galaxies. To deal with the SDSS data most effectively a new photometry software
was created, which is described in this paper. We present the results of the
selection algorithms applied to these 93 EDR fields. Two galaxies from the
Impey et al. test sample are very likely artifacts, as confirmed by follow-up
imaging. With our algorithms, we were able to recover 87 of the 90 remaining
test sample galaxies, implying a detection rate of 96.5%. The three
missed galaxies fall too close to very bright stars or galaxies. In addition,
42 new galaxies with parameters similar to the test sample objects were found
in these EDR fields (i.e., 47% additional galaxies). We present the main
photometric parameters of all identified galaxies and carry out first
statistical comparisons. We tested the quality of our photometry by comparing
the magnitudes for our test sample galaxies and other bright galaxies with
values from the literature. All these tests yielded consistent results. We
briefly discuss a few unusual galaxies found in our pilot study, including an
LSB galaxy with a two-component disk and ten new giant LSB galaxies.Comment: 36 pages, 16 figures, accepted for publication by AJ, some figures
were bitmapped to reduce the siz
The Tully-Fisher Relation and Its Residuals for a Broadly Selected Sample of Galaxies
We measure the relation between galaxy luminosity and disk circular velocity
(the Tully-Fisher [TF] relation), in the g, r, i, and z-bands, for a broadly
selected sample of galaxies from the Sloan Digital Sky Survey, with the goal of
providing well defined observational constraints for theoretical models of
galaxy formation. The input sample of 234 galaxies has a roughly flat
distribution of absolute magnitudes in the range -18.5 > Mr > -22, and our only
morphological selection is an axis-ratio cut b/a < 0.6 to allow accurate
inclination corrections. Long-slit spectroscopy yields usable H-alpha rotation
curves for 162 galaxies. Observational errors, including distance errors due to
peculiar velocities, are small compared to the intrinsic scatter of the TF
relation. The slope of the forward TF relation steepens from -5.5 +/- 0.2
mag/log(km/s) in the g-band to -6.6 +/- 0.2 mag/log(km/s) in the z-band. The
intrinsic scatter is approximately 0.4 mag in all bands. The scatter is not
dominated by rare outliers or by any particular class of galaxies, though it
drops slightly, to 0.36 mag, if we restrict the sample to nearly bulgeless
systems. Correlations of TF residuals with other galaxy properties are weak:
bluer galaxies are significantly brighter than average in the g-band but only
marginally brighter in the i-band; more concentrated galaxies are slightly
fainter than average; and the TF residual is virtually independent of
half-light radius, contrary to the trend expected for gravitationally dominant
disks. The observed residual correlations do not account for most of the
intrinsic scatter, implying that this scatter is instead driven largely by
variations in the ratio of dark to luminous matter within the disk galaxy
population.Comment: 23 figures, accepted by AJ, includes cosmological corrections to the
dat
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