2,793 research outputs found
Postpartum Management of Women with Gestational Diabetes
This case report highlights the importance of postpartum glucose screening, along with diabetes prevention education, for women with history of gestational diabetes mellitus (GDM). Gestational diabetes is a strong indicator of future type 2 diabetes. Postpartum screening allows providers opportunity for early detection of abnormal glucose levels in this vulnerable population (Frazzita, Anderson & Egan, 2013). Clinical practice guidelines establish routine postpartum care that include close monitoring of women with GDM. However, screening rates are as low as 33% among providers (Bihan et al., 2014; Hunt, Logan, Conway & Korte, 2010; Kapustin, 2008). The case description depicted in this paper illustrates a typical postpartum visit and how the primary provider can bridge the gap between clinical recommendations and practice by facilitating their implementation.
REFLEXIONES SOBRE LA TEORÍA Y LA PRÁCTICA DEL IVA EN COLOMBIA
Este trabajo discute, a la luz de la teoría tributaria, la manera de calcular el impuesto al valor agregado (IVA) de acuerdo con el Artículo 447 del Estatuto Tributario colombiano. El análisis teórico muestra que la implementación del IVA en Colombia no permite explotar todas las ventajas que el impuesto tiene en la teoría. En particular, la práctica colombiana induce cascadas tributarias y evita solo parcialmente las distorsiones en precios de bienes intermedios. A manera de ilustración, presentamos también una simulación numérica para ilustrar la magnitud del efecto de cascadas tributarias en el IVA colombiano. En este sentido, si bien el impuesto es claramente superior a un impuesto a las ventas en cada etapa de la cadena productiva, es bastante inferior al IVA teórico, resultando en tasas de tributación efectiva pueden ser el doble de las nominales. El documento demuestra, además, que la diferencia que se genera en precios según se use el método colombiano o el teórico, no genera diferencia en el recaudo real cuando el impuesto se aplica a todos los bienes. Es decir, mientras que el efecto de las cascadas será regresivo, el recaudo real no presentará variaciones.Impuesto al valor agregado incidencia tributaria cascadas
INCIDENCIA DEL IMPUESTO AL VALOR AGREGADO SOBRE LOS PRECIOS EN COLOMBIA
Este trabajo se centra en estimar el impacto que el impuesto al valor agregado (IVA) tiene sobre los precios al consumidor en Colombia. La estrategia de estimación aprovecha la frecuencia de las reformas tributarias, que generan abundante variación en las series de tiempo de tasas de impuestos. La identificación de los efectos del IVA sobre los precios se realiza utilizando series del índice de precios al consumidor (IPC) calculadas por el Departamento Administrativo Nacional de Estadística (DANE), la agencia oficial colombiana de estadísticas. Las estimaciones indican que en Colombia la incidencia del IVA sobre el precio de la canasta o pass-through es, a nivel nacional, estadísticamente igual a uno. El estudio también encuentra que la incidencia promedio es menor cuando se toman bienes individuales, sin ponderar por su importancia en la canasta de consumo, y controlando por la posibilidad que los mismos productos tengan características no observables distintas para cada ciudad. Este resultado resalta la heterogeneidad en la incidencia del impuesto a través de los mercados.Impuesto al valor agregado incidencia tributaria impuestos al consumo
Overcharging: The Crucial Role of Excluded Volume
In this Letter we investigate the mechanism for overcharging of a single
spherical colloid in the presence of aqueous salts within the framework of the
primitive model by molecular dynamics (MD) simulations as well as
integral-equation theory. We find that the occurrence and strength of
overcharging strongly depends on the salt-ion size, and the available volume in
the fluid. To understand the role of the excluded volume of the microions, we
first consider an uncharged system. For a fixed bulk concentration we find that
upon increasing the fluid particle size one strongly increases the local
concentration nearby the colloidal surface and that the particles become
laterally ordered. For a charged system the first surface layer is built up
predominantly by strongly correlated counterions. We argue that this a key
mechanism to produce overcharging with a low electrostatic coupling, and as a
more practical consequence, to account for charge inversion with monovalent
aqueous salt ions.Comment: 7 pages, 3 figs (4 EPS files). To appear in Europhysics Letter
Evolution of Magnetism in Single-Crystal Honeycomb Iridates
We report the successful synthesis of single-crystals of the layered iridate,
(NaLi)IrO, , and a thorough study of
its structural, magnetic, thermal and transport properties. The new compound
allows a controlled interpolation between NaIrO and LiIrO,
while maintaing the novel quantum magnetism of the honeycomb Ir planes.
The measured phase diagram demonstrates a dramatic suppression of the N\'eel
temperature, , at intermediate suggesting that the magnetic order in
NaIrO and LiIrO are distinct, and that at , the
compound is close to a magnetically disordered phase that has been sought after
in NaIrO and LiIrO. By analyzing our magnetic data with a
simple theoretical model we also show that the trigonal splitting, on the
Ir ions changes sign from NaIrO and LiIrO, and the
honeycomb iridates are in the strong spin-orbit coupling regime, controlled by
\jeff=1/2 moments.Comment: updated version with more dat
Passive Behavior and Passivity Breakdown of AISI 304 in LiBr Solutions through Scanning Electrochemical Microscopy
The passive behavior and passivity breakdown of AISI 304 stainless steel in LiBr solutions has been investigated by means of scanning electrochemical microscopy (SECM). The sample generation - tip collection (SG-TC) mode was used to operate the SECM and the tip potential was biased to detect the electroactive species. The evolution of the current at the ultramicroelectrode tip with the applied potential within the passive range was followed at different LiBr concentrations. Results show that the absolute value of the current at the tip increases with the applied potential. Additionally, SECM was also used to detect stable pits formed on the stainless steel surface in a 0.2 M LiBr solution. The results show clear evidence of the presence of high amounts of other reducible species (metal cations) apart from oxygen. Also, the dish-shape morphology of the pits observed using Confocal Laser Scanning Microscopy will be discussed in relation to the kinetics of the reactions observed using SECM. (c) 2014 The Electrochemical Society. All rights reserved.The authors would like to express their gratitude to the Generalitat Valenciana for its help in the SECM acquisition (PPC/2011/013) and in the CLSM acquisition (MY08/ISIRM/S/100) and to Dr. Asuncion Jaime for her translation assistance.Fernández Domene, RM.; Sánchez Tovar, R.; García Antón, J. (2014). Passive Behavior and Passivity Breakdown of AISI 304 in LiBr Solutions through Scanning Electrochemical Microscopy. Journal of The Electrochemical Society. 161(12):565-572. https://doi.org/10.1149/2.1051412jesS56557216112Cobb Harold M. (Ed.), Steel Products Manual: Stainless Steels, Iron & Steel Society, 1999.Schweitzer P. A. , Corrosion Engineering Handbook: Fundamentals of Metallic Corrosion, CRC Press, Boca Ratón, FL., 2007.Hakiki, N. 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Corrosion Science, 47(12), 3312-3323. doi:10.1016/j.corsci.2005.07.005Völker, E., Inchauspe, C. G., & Calvo, E. J. (2006). Scanning electrochemical microscopy measurement of ferrous ion fluxes during localized corrosion of steel. Electrochemistry Communications, 8(1), 179-183. doi:10.1016/j.elecom.2005.10.003Gabrielli, C., Joiret, S., Keddam, M., Perrot, H., Portail, N., Rousseau, P., & Vivier, V. (2007). A SECM assisted EQCM study of iron pitting. Electrochimica Acta, 52(27), 7706-7714. doi:10.1016/j.electacta.2007.03.008Yin, Y., Niu, L., Lu, M., Guo, W., & Chen, S. (2009). In situ characterization of localized corrosion of stainless steel by scanning electrochemical microscope. Applied Surface Science, 255(22), 9193-9199. doi:10.1016/j.apsusc.2009.07.003Santana, J. J., González-Guzmán, J., Fernández-Mérida, L., González, S., & Souto, R. M. (2010). Visualization of local degradation processes in coated metals by means of scanning electrochemical microscopy in the redox competition mode. Electrochimica Acta, 55(15), 4488-4494. doi:10.1016/j.electacta.2010.02.091González-García, Y., Santana, J. J., González-Guzmán, J., Izquierdo, J., González, S., & Souto, R. M. (2010). Scanning electrochemical microscopy for the investigation of localized degradation processes in coated metals. Progress in Organic Coatings, 69(2), 110-117. doi:10.1016/j.porgcoat.2010.04.006Yuan, Y., Li, L., Wang, C., & Zhu, Y. (2010). Study of the effects of hydrogen on the pitting processes of X70 carbon steel with SECM. Electrochemistry Communications, 12(12), 1804-1807. doi:10.1016/j.elecom.2010.10.031Aouina, N., Balbaud-Célérier, F., Huet, F., Joiret, S., Perrot, H., Rouillard, F., & Vivier, V. (2011). Single pit initiation on 316L austenitic stainless steel using scanning electrochemical microscopy. 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Spin waves in ultrathin ferromagnetic overlayers
The influence of a non-magnetic metallic substrate on the spin wave
excitations in ultrathin ferromagnetic overlayers is investigated for different
crystalline orientations. We show that spin wave dumping in these systems occur
due to the tunneling of holes from the substrate into the overlayer, and that
the spin wave energies may be considerably affected by the exchange coupling
mediated by the substrate.Comment: RevTeX 4, 7 pages, 5 figures; submitted to Phys. Rev.
Role of Modern Localised Electrochemical Techniques to Evaluate the Corrosion on Heterogeneous Surfaces
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