Financiarización de la vivienda para alquiler y la precarización de las familias de bajos ingresos en Medellín (Colombia)

La financiarización es una de las características actuales de la globalización y se ha manifestado fuertemente en la vivienda, haciendo que no sea un derecho fundamental sino un servicio por el que las familias de menores ingresos se deben endeudar. El objetivo de este artículo es analizar la financiarización de la vivienda en Medellín a través del alquiler y sus consecuencias para las familias de bajos ingresos. Utilizamos una metodología cualitativa basada en el análisis de información secundaria sobre arriendos, ingresos y pobreza, junto con su espacialización en la ciudad; además, hicimos una comparación con Cali (Colombia). Concluimos que mientras en países desarrollados esta financiarización se da a través de los Fondos de Inversión Inmobiliarios, en Colombia, particularmente en Medellín, la financiarización de la vivienda a través del alquiler se manifiesta cuando familias con excedentes de capital compran Viviendas de Interés Social, impulsadas por el Estado, y las arriendan a familias de menores ingresos: las destinatarias originales de estas políticas

Rat Adrenal Chromaffin Cells Are Neonatal CO2 Sensors

We studied the participation of adrenal medulla (AM) chromaffin cells in hypercapnic chemotransduction. Using amperometric recordings, we measured catecholamine (CAT) secretion from cells inAMslices of neonatal and adult rats perfused with solutions bubbled with different concentrations of CO2. The secretory activity augmented from 1.74_0.19 pC/min at 5% CO2 to 6.36_0.77 pC/min at 10% CO2. This response to CO2 was dose dependent and appeared without changes in extracellular pH, although it was paralleled by a drop in intracellular pH. Responsiveness to hypercapnia was higher in neonatal than in adult slices. The secretory response to hypercapnia required extracellular Ca2_ influx. Both the CO2-induced internal pH drop and increase in CAT secretion were markedly diminished by methazolamide (2_M), a membrane-permeant carbonic anhydrase (CA) inhibitor.Wedetected the presence of twoCAisoforms (CAI and CAII) in neonatalAMslices by in situ hybridization and real-time PCR. The expression of these enzymes decreased in adultAMtogether with the disappearance of responsiveness to CO2. In patch-clamped chromaffin cells, hypercapnia elicited a depolarizing receptor potential, which led to action potential firing, extracellular Ca2_ influx, and CAT secretion. This receptor potential (inhibited by methazolamide) was primarily attributable to activation of a resting cationic conductance. In addition, voltage-gated K_ current amplitude was also decreased by high CO2. The CO2-sensing properties of chromaffin cells may be of physiologic relevance, particularly for the adaptation of neonates to extrauterine life, before complete maturation of peripheral and central chemoreceptors

Multi-Proxy Approach for Identifying Heinrich Events in Sediment Cores from Hatton Bank (NE Atlantic Ocean)

A series of six gravity cores has been used to reconstruct the depositional history of Hatton Bank (Rockall Plateau, NE Atlantic Ocean). The cores have been studied for magnetic susceptibility (MS), geochemical composition, grain size distribution, and a semi-quantitative foraminiferal association. Two main interbedded facies have been described: (i) calcareous ooze; and (ii) lithogenous silt. The study reveals prominent peaks from the MS signal, silt, Mg/Ca, Fe/Ca, Al/Ca, and Rare Earth Elements normalised by Continental Crust (REE/CC), which are sensitive indicators for Heinrich events (H1, H2, H3, H4, and H5) and ash layers. These peaks may relate to alternations in dominance of the calcareous and lithogenic facies. The sediment displays a high percentage of carbonate in interglacial layers but is lithogenic-dominated in glacial stages. The layers with prominent lithic-rich and foraminifera-poor sediments (established as Heinrich layers) may be related to a possible palaeoclimatic effect, where freshwater discharged during iceberg melting may have reduced the formation of North Atlantic Deep Water (NADW). In the study area, the mean sedimentation rates for the last glacial as ~4.2 cm ka−1 and ~1.4 cm ka−1 for the last ~18 ka (interglacial period) have been estimated. Besides this evidence, Fe/Ca and MS peaks may reflect the presence of basalt, either introduced through ice-rafting or transported and redistributed by bottom currents in the study area. Certain indices, including MS and Fe/Ca, are proposed as good proxies for detecting Heinrich events and ash layers in the Hatton Bank sediments and, in consequence, are parameters that can be used to infer strengthened/weakened NADW formation, according to stadials/interstadials. Moreover, we suggest that the northernmost boundary of the area with evidence of Heinrich events may be situated around 57°38′ N in the Hatton–Rockall area, at least for H4, based on the variation of the Mg/Ca and Fe/Ca curves

Spatial Gradients of Intensity and Persistence of Soil Water Repellency Under Different Forest Types in Central Mexico

Organic residues release hydrophobic compounds to the soil that may induce soil water repellency (WR), which may inhibit infiltration andincrease runoff and soil loss rates. Although there are many studies on soil WR through the world, very few investigations have been con-ducted in Mexican areas. This paper studies the natural background of soil WR in soils from central Mexico under representative forest types,analyzing the spatial distribution of soil WR in relation with tree canopy, vegetation cover and main soil chemical (pH, CaCO3, organic Ccontent and exchangeable cations) and physical properties (texture). The water drop penetration time and the ethanol tests were used to assesspersistence and intensity of soil WR, respectively. Although soil WR was not related with soil properties, it decreased strongly from soil be-low the canopy of conifers to soil below oaks. When different types of vegetation cover were considered, the proportion of water-repellentsoil increased following the sequence: bare soil < shrubs and herbaceous plants < shrubs < trees from fir, fir-pine-oak and pine-oak forest.We found an inverse relation with distance to the tree trunks, contributing to create a patchy pattern of soil WR, with soils under the canopyof conifers showing the most severe WR levels. The spatial distribution of soil WR is also conditioned by microclimatic gradients, as per-sistence and intensity of soil WR were usually lower in shaded areas (upslope transects from the tree trunks), where soil moisture contentis expected to be higher on average through the year. Copyright © 2016 John Wiley & Sons, LtdMinisterio de Economía y Competitividad CGL2013-47862-C2-1-RMinisterio de Economía y Competitividad CGL 2012-38655-C04-0

Analysis of the geometric parameters influence in PCB fixtures for 2D multipole magnetization patterning of thin layer micro-magnets

Magnetic actuators, magnetic gears, vibrational energy harvesters and other micro-electromagnetic devices requires micro-magnetic rotors with alternant magnetizations to optimize their performance. Different approaches have been used for multipole magnetization of micro-magnets like fixed micro-fixtures, thermomagnetic patterning or laser machining. The main limitation of the previous techniques is that the inversion of the magnetic polarizations is only partially done. In this work, a concept based on 2D multipole magnetization printing of micro-magnets is proposed and analyzed to overcome current limitations. The fixtures are designed to be printed on a standard 35 μm PCB. The dependence of the magnetizing field with respect to the geometrical parameter of the fixture is analyzed. Maps of the required current for the magnetizing fields are also given. Some design recommendations to optimize the magnetizing field and to minimize current, thus the heat, are given.Universidad de Alcal

Segmented-block poly(ether amide)s containing flexible polydisperse polyethyleneoxide sequences and rigid aromatic amide moieties

We describe the synthesis and characterization of three novel aromatic diamines containing oxyethylene sequences of different lengths. These diamines were polymerized using the low-temperature solution polycondensation method with isophthaloyl chloride (IPC), terepthaloyl chloride (TPC), [1,1’-biphenyl]-4,4’-dicarbonyl dichloride (BDC), and 4,4′-oxybis(benzoyl chloride) (OBE), obtaining twelve poly(ether amide)s with short segments of polydisperse polyethyleneoxide (PEO) sequences in the polymer backbone. These polymers show reasonably high molecular mass materials (Mw > 12,000), and the relationship between their structure and properties has been carefully studied. Compared with conventional polyamides containing monodisperse PEO sequences, the polydispersity of the PEO segments within the structural units exerts a significant influence on the crystallinity, flexibility, solubility, and the thermal properties of the polymers. For instance, the all-para oriented polyamides (TPCP-A), with an average number of 8.2 ethylenoxide units per structural unit can be transformed conventionally (Tm = 259 °C) in comparison with thermally untransformable polymer with 2 ethylenoxide units (Tm = 425 °C)FEDER (Fondo Europeo de Desarrollo Regional), the Spanish Agencia Estatal de Investigación (PID2020-113264RB-I00/AEI/10.13039/501100011033) and (PID2019-108583RJ-I00/AEI/ 10.13039/501100011033), and the Consejería de Educación—Junta de Castilla y León (BU306P1

Heteroaromatic polyamides with Improved thermal and mechanical properties

We prepared high-performance aromatic copolyamides, containing bithiazole and thiazolo-thiazole groups in their main chain, from aromatic diamines and isophthaloyl chloride, to further improve the prominent thermal behavior and exceptional mechanical properties of commercial aramid fibers. The introduction of these groups leads to aramids with improved strength and moduli compared to commercial meta-oriented aromatic polyamides, together with an increase of their thermal performance. Moreover, their solubility, water uptake, and optical properties were evaluated in this work.Fondo Europeo de Desarrollo Regional and both the Spanish Ministerio de Economía, Industria y Competitividad (MAT2017-84501-R) and the Consejería de Educación, Junta de Castilla y León (BU306P18) is gratefully acknowledged. M.T.L. also thankfully acknowledges the Spanish Ministerio de Ciencia e Innovación (PID2019-108583RJ-I00/AEI/10.13039/501100011033

Case study: Analysis of time distribution in Physical Education

The use of time effectively as well as practice time is an important aspect for learning the contents of physical education. The aim of this study was to analyze and compare the distribution of time in: Compulsary Secondary Education and 1º Bachillerato. The motor activity and non-activity times were analyzed in 4 sessions at each level. The study involved 166 adolescents. The results showed similar time periods of motor and passive involvement, with no significant difference (p> 0.05) between the two: activity range between 45% and 55%. The higher levels of education (4th ESO and 1 Bachillerato) had higher practice time than the lower levels, with no significant differences between groups (F4, 13 = 31,019; p>0,05). Within the passive time, it was observed that the time devoted to the initial general information occupied at least 19.58%. The results allow to conclude that the level of education does not determine the time of motor activity of the physical education session. On the other hand, the low time of motor activity suggests the need to think about the time dedicated to the weekly physical activity and the education classes

Case study: Analysis of time distribution in Physical Education.

La utilización del tiempo de forma eficaz, así como el tiempo de práctica es un aspecto troncal de la Educación Física ya que de ello depende en gran medida el aprendizaje del alumnado. El presente trabajo tuvo por objetivo analizar y comparar la distribución del tiempo Educación Secundaria Obligatoria (ESO) y 1º Bachillerato. Para ello, se analizaron los tiempos motrices y pasivos de 4 sesiones en cada nivel, donde participaron 72 alumnos y 94 alumnas. Los resultados indicaron tiempos similares de tiempo compromiso motriz y pasivo, sin observarse diferencias significativas (p>0,05) entre ambos y con una oscilación entre el 45% y un 55%. Los niveles superiores de enseñanza (4º ESO y 1º Bachillerato) tuvieron mayores tiempos de práctica que los niveles inferiores, sin diferencias significativas entre grupos (F4, 13 = 31,019; p>0,05). Dentro del tiempo pasivo, se observó que el tiempo dedicado a la información inicial general ocupó al menos un 19,58%. Los resultados permiten concluir que los niveles de enseñanza no determinan el tiempo motriz de la sesión de Educación Física. Por otro lado, el bajo tiempo de compromiso motriz sugiere la necesidad de reflexionar sobre la actividad física semanal y tiempo dedicado a las clases de Educación Física.The use of time effectively as well as practice time is an important aspect for learning the contents of physical education. The aim of this study was to analyze and compare the distribution of time in: Compulsary Secondary Education and 1º Bachillerato. The motor activity and non-activity times were analyzed in 4 sessions at each level. The study involved 166 adolescents. The results showed similar time periods of motor and passive involvement, with no significant difference (p> 0.05) between the two: activity range between 45% and 55%. The higher levels of education (4th ESO and 1 Bachillerato) had higher practice time than the lower levels, with no significant differences between groups (F4, 13 = 31,019; p>0,05). Within the passive time, it was observed that the time devoted to the initial general information occupied at least 19.58%. The results allow to conclude that the level of education does not determine the time of motor activity of the physical education session. On the other hand, the low time of motor activity suggests the need to think about the time dedicated to the weekly physical activity and the education classes.peerReviewe

From Classical to Advanced Use of Polymers in Food and Beverage Applications

Polymers are extensively used in food and beverage packaging to shield against contaminants and external damage due to their barrier properties, protecting the goods inside and reducing waste. However, current trends in polymers for food, water, and beverage applications are moving forward into the design and preparation of advanced polymers, which can act as active packaging, bearing active ingredients in their formulation, or controlling the head-space composition to extend the shelf-life of the goods inside. In addition, polymers can serve as sensory polymers to detect and indicate the presence of target species, including contaminants of food quality indicators, or even to remove or separate target species for later quantification. Polymers are nowadays essential materials for both food safety and the extension of food shelf-life, which are key goals of the food industry, and the irruption of smart materials is opening new opportunities for going even further in these goals. This review describes the state of the art following the last 10 years of research within the field of food and beverage polymer’s applications, covering present applications, perspectives, and concerns related to waste generation and the circular economy.This work was supported by the Regional Government of Castilla y León (Junta de Castilla y León) and by the Ministry of Science and Innovation MICIN and the European Union NextGeneration EU PRTR. The project leading to these results has received funding from “La Caixa” Foundation, under the agreement LCF/PR/PR18/51130007. We also gratefully acknowledge the grant PID2020-113264RB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. Finally, we want to acknowledge the funding from Ministerio de UniversidadesEuropean Union in the frame of NextGenerationEU RD 289/2021 (Universidad Politécnica de Madrid and Universidad Autónoma de Madrid-CA1/RSUE/2021-00409)