High numerical aperture Mueller matrix polarimetry and applications to multiplexed optical data storage

Optical data storage has reached a point where it is no longer possible to increase the storage capacity of an optical disk by conventional means. The work presented here, however, proves experimentally the validity of a novel solution to increase the capacity of an optical disk. Polarisation is used to store information multiplexed into shape-birefringent pits. A high numerical aperture scanning confocal microscope capable of measuring the Muller matrix of a sample is built to measure and characterise the polarisation properties of such pits. A number of results found during the development of the apparatus are given. Novel contributions are shown in the areas of imaging, the theory of coherence and polarisation, polarisation imaging, linear algebra, polarisation confocal microscopy, and optical data storage. It is shown that the storage capacity of any existent non-volumetric optical technology can be increased by 7.16 times, at least

Optical Imaging of Surface Chemistry and Dynamics in Confinement

The interfacial structure and dynamics of water in a microscopically confined geometry is imaged in three dimensions and on millisecond time scales. We developed a 3D wide-field second harmonic microscope that employs structured illumination. We image pH induced chemical changes on the curved and confined inner and outer surfaces of a cylindrical glass micro-capillary immersed in aqueous solution. The image contrast reports on the orientational order of interfacial water, induced by charge-dipole interactions between water molecules and surface charges. The images constitute surface potential maps. Spatially resolved surface pKa,s values are determined for the silica deprotonation reaction. Values range from 2.3<pKa,s<10.7, highlighting the importance of surface heterogeneities. Water molecules that rotate along an oscillating external electric field are also imaged. With this approach, real time movies of surface processes that involve flow, heterogeneities and potentials can be made, which will further developments in electrochemistry, geology, catalysis, biology, and microtechnology

Modeling the biogeochemical seasonal cycle in the Strait of Gibraltar

A physical-biological coupled model was used to estimate the effect of the physical processes at the Strait of Gibraltar over the biogeochemical features of the Atlantic Inflow (AI) towards the Mediterranean Sea. This work was focused on the seasonal variation of the biogeochemical patterns in the AI and the role of the Strait; including primary production and phytoplankton features. As the physical model is 1D (horizontal) and two-layer, different integration methods for the primary production in the Biogeochemical Fluxes Model (BFM) have been evaluated. An approach based on the integration of a production-irradiance function was the chosen method. Using this Plankton Functional Type model (BFM), a simplified phytoplankton seasonal cycle in the AI was simulated. Main results included a principal bloom in spring dominated by nanoflagellates, whereas minimum biomass (mostly picophytoplankton) was simulated during summer. Physical processes occurring in the Strait could trigger primary production and raise phytoplankton biomass (during spring and autumn), mainly due to two combined effects. First, in the Strait a strong interfacial mixing (causing nutrient supply to the upper layer) is produced, and, second, a shoaling of the surface Atlantic layer occurs eastward. Our results show that these phenomena caused an integrated production of 105 g C m− 2 year− 1 in the eastern side of the Strait, and would also modify the proportion of the different phytoplankton groups. Nanoflagellates were favored during spring/autumn while picophytoplankton is more abundant in summer. Finally, AI could represent a relevant source of nutrients and biomass to Alboran Sea, fertilizing the upper layer of this area with 4.95 megatons nitrate year− 1 (79.83 gigamol year− 1) and 0.44 megatons C year− 1. A main advantage of this coupled model is the capability of solving relevant high-resolution processes as the tidal forcing without expensive computing requirements, allowing to assess the effect of these phenomena on the biogeochemical patterns at longer time scales

Probing Rotational and Translational Diffusion of Nanodoublers in Living Cells on Microsecond Time Scales

Nonlinear microscopes have seen an increase in popularity in the life sciences due to their molecular and structural specificity, high resolution, large penetration depth, and volumetric imaging capability. Nonetheless, the inherently weak optical signals demand long exposure times for live cell imaging. Here, by modifying the optical layout and illumination parameters, we can follow the rotation and translation of noncentrosymetric crystalline particles, or nanodoublers, with 50 mu s acquisition times in living cells. The rotational diffusion can be derived from variations in the second harmonic intensity that originates from the rotation of the nanodoubler crystal axis. We envisage that by capitalizing on the biocompatibility, functionalizability, stability, and nondestructive optical response of the nanodoublers, novel insights on cellular dynamics are within reach

Further Characterization of the Electrogenicity and pH Sensitivity of the Human Organic Anion-Transporting Polypeptides OATP1B1 and OATP1B3

Organic anion-transporting polypeptides (OATPs) are involved in the liver uptake of many endogenous and xenobiotic compounds, such as bile acids and drugs, respectively. Using Xenopus laevis oocytes and Chinese hamster ovary (CHO) cells expressing rat Oatp1a1, human OATP1B1, or OATP1B3, the sensitivity of these transporters to extracellular/intracellular pH (pHo/pHi) and changes in plasma membrane potential (ΔΨ) was investigated. In X. laevis oocytes, nonspecific plasma membrane permeability increased only at pHo below 4.5. Above this value, both using oocytes and CHO cells, extracellular acidification affected differently the specific transport of taurocholic acid (TCA) and estradiol 17β-d-glucuronide (E217βG) by Oatp1a1 (stimulation), OATP1B1 (inhibition), and OATP1B3 (stimulation). Changes in substrate uptake in the presence of valinomycin (K+-ionophore), carbonyl cyanide 3-chlorophenylhydrazone and nigericin (protonophores), and amiloride (Na+/H+-inhibitor) and cation replacement in the medium were studied with fluorescent probes for measuring substrate uptake (cholylglycyl amidofluorescein) and changes in pHi (SNARF-4F) and ΔΨ [DilC1(5)]. The results suggest that activity of these three carriers is sodium/potassium-independent and affected differently by changes in pHo and ΔΨ: Oatp1a1 was confirmed to be an electroneutral anion exchanger, whereas the function of both OATP1B1 and OATP1B3 was markedly affected by the magnitude of ΔΨ. Moreover, electrophysiological measurements revealed the existence of a net anion influx associated to OATP1B1/OATP1B3-mediated transport of TCA, E217βG, and estrone-3-sulfate. Furthermore, a leakage of Na+ through OATP1B1 and OATP1B3, which is not coupled to substrate transport, was found. In conclusion, these results suggest that OATP1B1 and OATP1B3 are electrogenic transporters whose activity may be strongly affected under circumstances of displacement of local pH

High throughput second harmonic imaging for label-free biological applications

Second harmonic generation (SHG) is inherently sensitive to the absence of spatial centrosymmetry, which can render it intrinsically sensitive to interfacial processes, chemical changes and electrochemical responses. Here, we seek to improve the imaging throughput of SHG microscopy by using a wide-field imaging scheme in combination with a medium-range repetition rate amplified near infrared femtosecond laser source and gated detection. The imaging throughput of this configuration is tested by measuring the optical image contrast for different image acquisition times of BaTiO3 nanoparticles in two different wide-field setups and one commercial point-scanning configuration. We find that the second harmonic imaging throughput is improved by 2-3 orders of magnitude compared to point-scan imaging. Capitalizing on this result, we perform low fluence imaging of (parts of) living mammalian neurons in culture. (C) 2014 Optical Society of Americ

Generations No.7: Annual rendezvous with culture

Nuestra Institución se mueve articulada en tres ejes misionales: docencia, investigación y extensión; es precisamente en esta última, como parte de la labor de extensión cultural de la Universidad, que anualmente efectuamos la Feria del Libro de Bucaramanga, Ulibro. Cito al periodista mexicano Sergio González Rodríguez: “Tenemos que reaprender que la literatura no es solo entretener, tiene que servir para pensar, para analizar”, y a eso le apuesta la UNAB desde hace 12 años con Ulibro: una excusa para promover la cultura y el hábito de la lectura.Editorial; Por Alberto Montoya Puyana…3 Ulibro; Por Laura Camila Romero Martínez…4 La voz del graduado…6 Recomendaciones para elaborar una hoja de vida; Por Ana Carolina Torres P.…8 ABC de los posgrados; Por Carolina Toscano V....10 Comunicación y Artes Mensaje integral; Por Claudia Santamaría Valbuena…16 La conversación como salud; Por Carlos Germán Celis E....18 Ciudades inteligentes; Por Clara Inés Peña de Carrillo…20 Educación farmacéutica; Por Yaneth Rocío Orellana Hernández y Sergio Daniel Quiroga Flórez…22 La enseñanza del Derecho; Por Mario Guevara Mendoza…25 También comienza por casa; Por Hugo F. Prada A…28 Los macroproyectos Investigaciones UNAB; Por Miguel Ángel Hernández Rey…30 Graduados destacados; Por Redacción Generaciones UNAB…34 Generaciones en cifras; Por Redacción Generaciones UNAB…42 Centro de Apoyo y Formación Empresarial; Por Redacción Generaciones UNAB…43 6ª Feria del Empleo; Por Redacción Generaciones UNAB…46 Encuentros…48Our Institution moves articulated in three missionary axes: teaching, research and extension; It is precisely in the latter, as part of the cultural outreach work of the University, that we annually hold the Bucaramanga Book Fair, Ulibro. I quote the Mexican journalist Sergio González Rodríguez: “We have to relearn that literature is not only entertaining, it has to serve to think, to analyze”, and that is what the UNAB has been betting on for 12 years with Ulibro: an excuse to promote culture and the habit of reading

The DESI Bright Galaxy Survey: Final Target Selection, Design, and Validation

Over the next 5 yr, the Dark Energy Spectroscopic Instrument (DESI) will use 10 spectrographs with 5000 fibers on the 4 m Mayall Telescope at Kitt Peak National Observatory to conduct the first Stage IV dark energy galaxy survey. At z 10 million galaxies spanning 14,000 deg2 . In this work, we present and validate the final BGS target selection and survey design. From the Legacy Surveys, BGS will target an r 80% fiber assignment efficiency. Finally, BGS Bright and BGS Faint will achieve >95% redshift success over any observing condition. BGS meets the requirements for an extensive range of scientific applications. BGS will yield the most precise baryon acoustic oscillation and redshift-space distortion measurements at z < 0.4. It presents opportunities for new methods that require highly complete and dense samples (e.g., N-point statistics, multitracers). BGS further provides a powerful tool to study galaxy populations and the relations between galaxies and dark matter

Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

Ciencias Sociales: Economía y Humanidades

Este volumen I contiene 29 capítulos arbitrados que se ocupan de estos asuntos en Tópicos Selectos de Ciencias Sociales: Economía y Humanidades, elegidos de entre las contribuciones, reunimos algunos investigadores y estudiantes.Gómez, presenta un breve examen de la producción y comercialización de rosa en México; Arpi y Portillo realiza un estudio en México sobre el ingreso mínimo de las familias que identifica la línea de pobreza alimentaria en el área rural del sur de México, 2012; Bravo realiza un pequeño estudio donde hablará sobre el análisis comparado del Sector Gubernamental y la Economía Mexicana desde la perspectiva de los eslabonamientos productivos Hirshman-Rasmuss; Caamal, Pat, Jerónimo y Romero realizan un estudio sobre los canales de comercialización de limón persa en el municipio de Martínez de la Torre, Veracruz; Macías y Perales nos hablarán sobre una análisis del comercio estratégico en el TLCAN: El Estado en la política agrícola de biocombustibles; Figueroa, Pérez y Godínez se expresan acerca de la importancia de la comercialización del café en México; Sepúlveda, Sepúlveda y Pérez realizan un diagnóstico, retos del comercio electrónico en el Sector Agroindustrial Mexicano; Duana mediante su trabajo nos muestra y habla sobre la inversión extranjera directa y su impacto en crecimiento de México, un análisis en prospectiva: 1999-2010; Figueroa, Pérez y Ramírez hacen un estudio acerca sobre la importancia de la Banca en México; Pérez, Figueroa, Godínez y Pérez presenta un trabajo acerca de la competitividad de la producción agrícola en México, un análisis regional; Rodríguez, Espinosa y Márquez analizan todo acerca de el SIAL productor de quesos en Poxtla, competividad y territorio; Garza nos habla acerca de la intermediación financiera al servicio de la comunidad indígena: el fondo regional indígena Tarhiata Keri; Arroyo, Aguilar, Santoyo y Muñoz realizan un estudio acerca de la demanda de Importaciones de durazno (Prunus pérsica L. Batsch) en México procedentes de Estados Unidos de América (1982-2011); Loera y Sepúlveda analizan los parámetros de la productividad forestal en la producción de madera en rollo; Pérez, Morett y Tecpan realizan un análisis de factores sociales, ambientales y económicos del territorio rural cercano a la ciudad de México; Godínez, Figueroa y Pérez realizan un estudio acerca de la crisis económica mundial y su efecto sobre los flujos migratorios de América Latina; Magadán, Hernández y Escalona presentan la tipología de los sujetos sociales que intervienen en el mercado campesino de Ocotlán Oaxaca; Tavera y Cobos nos hablan de la normalización del proceso de compostaje: una opción para desarrollar el mercado de la composta; Piña y Pérez hablan acerca de la reestructuración del capitalismo y crisis política en México; Gonzáles, Rucoba y Ramírez realizan un estudio de la rentabilidad de la producción de miel en el municipio de León, Guanjuato; Ramírez, Gutiérrez y Figueroa realizan un estudio acerca de la economía del maíz en la región metropolitana, Chiapas, 2014; Bueno, Méndez y Cruz realizan un estudio y análisis de los centros de educación y cultura ambiental, necesidad de profesionalización Pedagógica de facilitadores ambientales; Pat, Caamal, Jerónimo y Mendoza presentan un estudio acerca de los Costos y competitividad de la producción del limón persa en el municipio de Martínez de la Torre, Veracruz. Vizuet presenta un trabajo de la construcción polisémica e histórica del concepto de la pobreza; Navarrete, Ríos y Arévalo presentan un estudio acerca de la producción ejidal de tomate rojo (Lycopersicum esculentum) en el DR-017, y su huella hídrica; Pérez y Piña hablan acerca de la productividad e inversión extranjera: La industria de Alimentos; Pérez, Figueroa, Godínez y Gómez presentan el trabajo sobre el sector primario en México; Pérez, Figueroa, Godínez y Gómez presentan acerca de los subsidios al campo como instrumento de política económica en México; Venegas, Perales y Del Valle realizan un estudio de rentabilidad de biodigestores y motogeneradores para diferentes tamaños de granjas porcinas en Michoacán