Dependence of exchange anisotropy and coercivity on the Fe–oxide structure in oxygen-passivated Fe nanoparticles

Ultrafine Fe particles have been prepared by the inert gas condensation method and subsequently oxygen passivated. The as-obtained particles consist in an Fe core surrounded by an amorphous Fe-oxide surface layer. The antiferromagnetic character of the Fe-oxide surface induces an exchange anisotropy in the ferromagnetic Fe core when the system is field cooled. Samples have been heat treated in vacuum at different temperatures. Structural changes of the Fe–O layer have been monitored by x-ray diffraction and transmission electron microscopy. Magnetic properties as coercivity, hysteresis loop shift, and evolution of magnetization with temperature have been analyzed for different oxide crystallization stages. A decrease of the exchange anisotropy strength is reported as the structural disorder of the surface oxide layer is decreased with thermal treatment

Los edificios de paneles más altos de España

RESUMEN Este artículo describe el proceso constructivo de un conjunto de 484 viviendas realizadas con paneles prefabricados portantes de hormigón. Dicho conjunto edi¿catorio, de 20 plantas de altura, se compone de diversos bloques que integran además, locales comerciales, o¿cinas, trasteros, 4 plantas de garaje e instalaciones comunes. El principal interés de este edi¿cio consiste en haber alcanzado veinte plantas sobre rasante y 4 más de sótano con el sistema constructivo de paneles prefabricados de hormigón INDAGSA; el cual dispone de un Documento de Idoneidad Técnica emitido por el IETcc, con el número DIT 452. Las obras de INDAGSA son conocidas por ser precisas, ordenadas y limpias; debido a estas características, se pudieron establecer visitas no sólo para doctorandos de la ETSAM, sino para estudiantes de la Cátedra de sistemas industrializados y prefabricados. A través de la descripción del sistema constructivo, podremos mostrar una perspectiva global de las posibilidades de los sistemas de paneles prefabricados de hormigón y las capacidades evolutivas de éstos

Dependence of exchange anisotropy and coercivity on the Fe–oxide structure in oxygen-passivated Fe nanoparticles

Ultrafine Fe particles have been prepared by the inert gas condensation method and subsequently oxygen passivated. The as-obtained particles consist in an Fe core surrounded by an amorphous Fe-oxide surface layer. The antiferromagnetic character of the Fe-oxide surface induces an exchange anisotropy in the ferromagnetic Fe core when the system is field cooled. Samples have been heat treated in vacuum at different temperatures. Structural changes of the Fe–O layer have been monitored by x-ray diffraction and transmission electron microscopy. Magnetic properties as coercivity, hysteresis loop shift, and evolution of magnetization with temperature have been analyzed for different oxide crystallization stages. A decrease of the exchange anisotropy strength is reported as the structural disorder of the surface oxide layer is decreased with thermal treatment

Endothelial Transcytosis of Lipoproteins in Atherosclerosis

Seminal studies from Nikolai Anichckov identified the accumulation of cholesterol in the arteries as the initial event that lead to the formation of atherosclerotic plaques. Further studies by Gofman and colleagues demonstrated that high levels of circulating low-density lipoprotein cholesterol (LDL-C) was responsible for the accelerated atherosclerosis observed in humans. These findings were confirmed by numerous epidemiological studies which identified elevated LDL-C levels as a major risk factor for cardiovascular disease. LDL infiltrates in the arterial wall and interacts with the proteoglycan matrix promoting the retention and modification of LDL to a toxic form, which results in endothelial cell (EC) activation and vascular inflammation. Despite the relevance of LDL transport across the endothelium during atherogenesis, the molecular mechanism that control this process is still not fully understood. A number of studies have recently demonstrated that low density lipoprotein (LDL) transcytosis across the endothelium is dependent on the function of caveolae, scavenger receptor B1 (SR-B1), activin receptor-like kinase 1 (ALK1), and LDL receptor (LDLR), whereas high-density lipoproteins (HDL) and its major protein component apolipoprotein AI transcytose ECs through SR-B1, ATP-Binding cassette transporter A1 (ABCA1) and ABCG1. In this review article, we briefly summarize the function of the EC barrier in regulating lipoprotein transport, and its relevance during the progression of atherosclerosis. A better understanding of the mechanisms that mediate lipoprotein transcytosis across ECs will help to develop therapies targeting the early events of atherosclerosis and thus exert potential benefits for treating atherosclerotic vascular disease

Dependence of exchange anisotropy and coercivity on the Fe–oxide structure in oxygen-passivated Fe nanoparticles

3 pages, 5 figures.Ultrafine Fe particles have been prepared by the inert gas condensation method and subsequently oxygen passivated. The as-obtained particles consist in an Fe core surrounded by an amorphous Fe-oxide surface layer. The antiferromagnetic character of the Fe-oxide surface induces an exchange anisotropy in the ferromagnetic Fe core when the system is field cooled. Samples have been heat treated in vacuum at different temperatures. Structural changes of the Fe–O layer have been monitored by x-ray diffraction and transmission electron microscopy. Magnetic properties as coercivity, hysteresis loop shift, and evolution of magnetization with temperature have been analyzed for different oxide crystallization stages. A decrease of the exchange anisotropy strength is reported as the structural disorder of the surface oxide layer is decreased with thermal treatment.Peer reviewe

La depresión infantojuvenil: prevención en un Instituto de Enseñanza Secundaria

La infancia se acorta por la actividad a que los adultos someten a los niños/as, y la adolescencia se prolonga artificialmente, porque el período de dependencia económica y psicosocial no coincide con el de autonomía física que se consolida en la pubertad. La sociedad, las familias, la escolaridad, las circunstancias... en muchas ocasiones hacen que los niños/as y adolescentes tengan dificultades de adaptación que se manifiestan en conductas de depresión, que se prolongan o surgen en la adultez. Se proponen las bases de un Programa de (Intervención desde la) Prevención, en un Instituto de Enseñanza Secundaria, desde el Departamento de Orientación, con la colaboración de los tutores del centro, las familias, y con la implicación de toda la comunidad educativa.Childhood is shortened by the activity that adults subject children and adolescence is extended artificially, because the period of psychological and economic dependency does not coincide with the physical autonomy which is consolidated at puberty. The society, families, schooling, the circumstances... on many occasions make that children and adolescents have difficulties of adaptation that is manifested in behavior of depression, which extend or arise in adulthood. We propose the bases of a program of (intervention from the) prevention, in an Institute of secondary education, from the guidance Department, with the collaboration of the Center, families, tutors and with the involvement of the entire educational communityEste trabajo pretende dar a conocer la importancia de la prevención de la depresión infantojuvenil en un Instituto de Enseñanza Secundaria, mediante la elaboración de las bases de un Programa de intervención desde el Departamento de Orientación, con la colaboración de los tutores del centro, las familias, y con la implicación de toda la comunidad educativa

¿Es útil la disuria para el diagnóstico de la infección del tracto urinario?

ObjetivoDeterminar la validez de criterio y el valor predictivo del síntoma disuria para el diagnóstico de infección del tracto urinario (ITU).DiseñoEstudio transversal para evaluación de un síntoma.EmplazamientoSeis consultas de atención primaria (4 de zona urbana y 2 rurales) del Área 11 de Salud de Madrid.ParticipantesSe incluyeron 232 pacientes mayores de 14 años que acudieron a consulta durante 6 meses consecutivos (116 consultaron por disuria y 116 asintomáticos para el síntoma disuria). A todos se les solicitó sedimento y urocultivo.Mediciones y resultadosSe estableció diagnóstico de ITU con urocultivo positivo o sedimento con leucocituria y bacteriuria. Se estudio la sensibilidad (S), especificidad (E), el valor predictivo positivo (VPP), el valor predictivo negativo (VPN), el cociente de probabilidades positivo (CPP) y el cociente de probabilidades negativo (CPN) de la disuria para el diagnóstico de ITU. La edad media fue de 54 años (rango, 19–82), siendo un 73% mujeres. No había diferencias significativas de edad y sexo entre casos y no casos (p > 0,1). La disuria mostró una S del 96% (IC del 95%, 86–98%), una E del 69% (IC del 95%, 61–76%) y un CPP de 3,1 (IC del 95%, 2,7–3,5) para el diagnóstico de ITU. En el subgrupo de mujeres la S fue del 95% (IC del 95%, 84–99%) y la E del 67% (IC del 95%, 58–75%). Se calculó para este síntoma un VPP del 30% (IC del 95%, 22–40%) y un VPN del 99% (IC del 95%, 95–100%).ConclusionesEs poco probable el diagnóstico de ITU sin el síntoma disuria. La mayoría de los pacientes con ITU presentan disuria; sin embargo, este síntoma aislado no nos permite establecer el diagnostico de infección urinaria.ObjectiveTo assess the validity of criterion and predictive value of dysuria for the diagnosis of UTI.DesignCross-sectional study to assess a symptom.SettingSix general medicine clinics (four urban clinics and two rural clinics) in the 11th Health Area in Madrid.PatientsThe sample consists of 232 patients aged above fourteen who consulted during six consecutive months (116 of them reported having dysuria and 116 were asymptomatic).Measurements and main resultsThe diagnosis of urinary tract infections (UTI) was achieved through positive urine cultures or bacteriuria and leukocyturia in the centrifuged urine sediment. The sensitivity (S) of dysuria analysis for the diagnosis of UTI, its specifity (E), its predictive value (VP), and its probability coeficient (CP) were considered. Average age of the sample was 54 years old (range 19–82); 73% of the patients were female. No statistically significative difference of sex and age was found between cases and non-cases (p > 0.1). Dysuria showed a 96% of sensitivity (95% CI, 86–98%), a 69% of E (95% CI, 61–76%) and 3.1 of CPP (95% CI, 2.7–3.5) for UTI diagnosis. In the women subgroup there was 95% of sensitivity (95% CI, 84–99%) and 67% of E (95% CI, 58–75%). A positive predictive value of 30% (95% CI, 22–40) and a negative predictive value of 99% (95% CI, 95–100) were estimated for this symptom.ConclusionsThe diagnosis of urinary tract infections is unlikely in the absence of dysuria, but to treat all dysuria patients as UTI entails a high rate of overtreatment

Development of a dynamic energy-partitioning model for enteric methane emissions and milk production in goats using energy balance data from indirect calorimetry studies

[EN] The main objective of this study was to develop a dynamic energy balance model for dairy goats to describe and quantify energy partitioning between energy used for work (milk) and that lost to the environment. Increasing worldwide concerns regarding livestock contribution to global warming underscore the importance of improving energy efficiency utilization in dairy goats by reducing energy losses in feces, urine and methane (CH4). A dynamic model of CH(4)emissions from experimental energy balance data in goats is proposed and parameterized (n= 48 individual animal observations). The model includes DM intake, NDF and lipid content of the diet as explanatory variables for CH(4)emissions. An additional data set (n= 122 individual animals) from eight energy balance experiments was used to evaluate the model. The model adequately (root MS prediction error,RMSPE) represented energy in milk (E-milk;RMSPE = 5.6%), heat production (HP;RMSPE = 4.3%) and CH(4)emissions (E-CH4; RMSPE = 11.9%). Residual analysis indicated that most of the prediction errors were due to unexplained variations with small mean and slope bias. Some mean bias was detected for HP (1.12%) and E-CH4(1.27%) but was around zero for E-milk (0.14%). The slope bias was zero for HP (0.01%) and close to zero for E-milk (0.10%) and E-CH4(0.22%). Random bias was >98% for E-CH4, HP and E-milk, indicating non-systematic errors and that mechanisms in the model are properly represented. As predicted energy increased, the model tended to underpredict E-CH(4)and E-milk. The model is a first step toward a mechanistic description of nutrient use by goats and is useful as a research tool for investigating energy partitioning during lactation. The model described in this study could be used as a tool for making enteric CH(4)emission inventories for goats.This study was supported by LOW CARBON FEED Project reference LIFE2016/CCM/ES/000088.Fernández Martínez, CJ.; Hernando, I.; Moreno-Latorre, E.; Loor, J. (2020). Development of a dynamic energy-partitioning model for enteric methane emissions and milk production in goats using energy balance data from indirect calorimetry studies. Animal. 14:s382-s395. https://doi.org/10.1017/S1751731120001470Ss382s39514Agricultural and Food Research Council (AFRC) 1997. The nutrition of goats. Nutrition Abstract and Reviews (Series B) 67, 776–861.Aguilera, J. F., Prieto, C., & FonollÁ, J. (1990). Protein and energy metabolism of lactating Granadina goats. British Journal of Nutrition, 63(2), 165-175. doi:10.1079/bjn19900104Bannink, A., France, J., Lopez, S., Gerrits, W. J. J., Kebreab, E., Tamminga, S., & Dijkstra, J. (2008). Modelling the implications of feeding strategy on rumen fermentation and functioning of the rumen wall. Animal Feed Science and Technology, 143(1-4), 3-26. doi:10.1016/j.anifeedsci.2007.05.002Bava, L., Rapetti, L., Crovetto, G. M., Tamburini, A., Sandrucci, A., Galassi, G., & Succi, G. (2001). Effects of a Nonforage Diet on Milk Production, Energy, and Nitrogen Metabolism in Dairy Goats throughout Lactation. Journal of Dairy Science, 84(11), 2450-2459. doi:10.3168/jds.s0022-0302(01)74695-4Beauchemin K, McAllister T and McGinn S 2009. Dietary mitigation of enteric CH4 from cattle. CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources 4, 035.Blaxter, K. L., & Clapperton, J. L. (1965). Prediction of the amount of methane produced by ruminants. British Journal of Nutrition, 19(1), 511-522. doi:10.1079/bjn19650046Brouwer E 1965. Report of sub-committee on constants and factors. In Proceeding of the 3th EAAP Symposium on Energy Metabolism (ed. KL Blaxter ), pp. 441–443. Academic Press, London, UK.Criscioni, P., Marti, J. V., Pérez-Baena, I., Palomares, J. L., Larsen, T., & Fernández, C. (2016). Replacement of alfalfa hay ( Medicago sativa ) with maralfalfa hay ( Pennisetum sp.) in diets of lactating dairy goats. Animal Feed Science and Technology, 219, 1-12. doi:10.1016/j.anifeedsci.2016.05.020Ellis, J. L., Kebreab, E., Odongo, N. E., McBride, B. W., Okine, E. K., & France, J. (2007). Prediction of Methane Production from Dairy and Beef Cattle. Journal of Dairy Science, 90(7), 3456-3466. doi:10.3168/jds.2006-675Statistical data base Food and Agriculture Organization (FAOSTAT) 2018. FAO Statistical data base Food and Agriculture Organization of the United Nations, Rome, Italy. Retrieved on 25 June 2018 from http://faostat.fao.org/FERNÁNDEZ, C., LÓPEZ, M. C., & LACHICA, M. (2015). Low-cost mobile open-circuit hood system for measuring gas exchange in small ruminants: from manual to automatic recording. The Journal of Agricultural Science, 153(7), 1302-1309. doi:10.1017/s0021859615000416Fernández, C., Martí, J. V., Pérez-Baena, I., Palomares, J. L., Ibáñez, C., & Segarra, J. V. (2018). Effect of lemon leaves on energy and C–N balances, methane emission, and milk performance in Murciano-Granadina dairy goats. Journal of Animal Science, 96(4), 1508-1518. doi:10.1093/jas/sky028Fernández, C. (2018). Dynamic model development of enteric methane emission from goats based on energy balance measured in indirect open circuit respiration calorimeter. Global Ecology and Conservation, 15, e00439. doi:10.1016/j.gecco.2018.e00439Fernández, C., Pérez-Baena, I., Marti, J. V., Palomares, J. L., Jorro-Ripoll, J., & Segarra, J. V. (2019). Use of orange leaves as a replacement for alfalfa in energy and nitrogen partitioning, methane emissions and milk performance of murciano-granadina goats. Animal Feed Science and Technology, 247, 103-111. doi:10.1016/j.anifeedsci.2018.11.008Fernández, C., Gomis-Tena, J., Hernández, A., & Saiz, J. (2019). An Open-Circuit Indirect Calorimetry Head Hood System for Measuring Methane Emission and Energy Metabolism in Small Ruminants. Animals, 9(6), 380. doi:10.3390/ani9060380Grainger, C., & Beauchemin, K. A. (2011). Can enteric methane emissions from ruminants be lowered without lowering their production? Animal Feed Science and Technology, 166-167, 308-320. doi:10.1016/j.anifeedsci.2011.04.021Howarth, R. (2015). Methane emissions and climatic warming risk from hydraulic fracturing and shale gas development: implications for policy. Energy and Emission Control Technologies, 45. doi:10.2147/eect.s61539Hristov, A. N., Kebreab, E., Niu, M., Oh, J., Bannink, A., Bayat, A. R., … Yu, Z. (2018). Symposium review: Uncertainties in enteric methane inventories, measurement techniques, and prediction models. Journal of Dairy Science, 101(7), 6655-6674. doi:10.3168/jds.2017-13536Ibáñez, C., López, M. C., Criscioni, P., & Fernández, C. (2015). Effect of replacing dietary corn with beet pulp on energy partitioning, substrate oxidation and methane production in lactating dairy goats. Animal Production Science, 55(1), 56. doi:10.1071/an13119Institute Nationale Recherche Agronomique (INRA) 2017. Feeding system for ruminants. Wageningen Academic Publishers, Wageningen, the Netherlands.Jørgensen, S. E. (2015). New method to calculate the work energy of information and organisms. Ecological Modelling, 295, 18-20. doi:10.1016/j.ecolmodel.2014.09.001Kebreab, E., Johnson, K. A., Archibeque, S. L., Pape, D., & Wirth, T. (2008). Model for estimating enteric methane emissions from United States dairy and feedlot cattle1. Journal of Animal Science, 86(10), 2738-2748. doi:10.2527/jas.2008-0960Knapp, J. R., Laur, G. L., Vadas, P. A., Weiss, W. P., & Tricarico, J. M. (2014). Invited review: Enteric methane in dairy cattle production: Quantifying the opportunities and impact of reducing emissions. Journal of Dairy Science, 97(6), 3231-3261. doi:10.3168/jds.2013-7234Lin, L. I.-K. (1989). A Concordance Correlation Coefficient to Evaluate Reproducibility. Biometrics, 45(1), 255. doi:10.2307/2532051López, M. C., Estellés, F., Moya, V. J., & Fernández, C. (2014). Use of dry citrus pulp or soybean hulls as a replacement for corn grain in energy and nitrogen partitioning, methane emissions, and milk performance in lactating Murciano-Granadina goats. Journal of Dairy Science, 97(12), 7821-7832. doi:10.3168/jds.2014-8424López, M. C., & Fernández, C. (2013). Energy partitioning and substrate oxidation by Murciano-Granadina goats during mid lactation fed soy hulls and corn gluten feed blend as a replacement for corn grain. Journal of Dairy Science, 96(7), 4542-4552. doi:10.3168/jds.2012-6473Martí JV, Pérez-Baena I and Fernández C 2012. Replacement of barley grain with lemon pulp on energy partitioning in lactating goats. Unpublished.Merino, P., Ramirez-Fanlo, E., Arriaga, H., del Hierro, O., Artetxe, A., & Viguria, M. (2011). Regional inventory of methane and nitrous oxide emission from ruminant livestock in the Basque Country. Animal Feed Science and Technology, 166-167, 628-640. doi:10.1016/j.anifeedsci.2011.04.081Mills, J. A. N., Kebreab, E., Yates, C. M., Crompton, L. A., Cammell, S. B., Dhanoa, M. S., … France, J. (2003). Alternative approaches to predicting methane emissions from dairy cows1. Journal of Animal Science, 81(12), 3141-3150. doi:10.2527/2003.81123141xMoorby, J. M., Fleming, H. R., Theobald, V. J., & Fraser, M. D. (2015). Can live weight be used as a proxy for enteric methane emissions from pasture-fed sheep? Scientific Reports, 5(1). doi:10.1038/srep17915Niu, M., Kebreab, E., Hristov, A. N., Oh, J., Arndt, C., Bannink, A., … Yu, Z. (2018). Prediction of enteric methane production, yield, and intensity in dairy cattle using an intercontinental database. Global Change Biology, 24(8), 3368-3389. doi:10.1111/gcb.14094Patra, A. K., & Lalhriatpuii, M. (2016). Development of statistical models for prediction of enteric methane emission from goats using nutrient composition and intake variables. Agriculture, Ecosystems & Environment, 215, 89-99. doi:10.1016/j.agee.2015.09.018Pérez-Baena I, Martí JV and Fernández C 2012. Effect of replace barley grain with beet pulp in lactating goats diet; energy balance and milk performance. Unpublished.R Core Team 2016. R: A language and environment for statistical computing. Version 1.1.447. R Foundation for Statistical Computing, Vienna, Austria. Retrieved from https://www.R-project.org/Ramin, M., & Huhtanen, P. (2013). Development of equations for predicting methane emissions from ruminants. Journal of Dairy Science, 96(4), 2476-2493. doi:10.3168/jds.2012-6095Tovar-Luna, I., Puchala, R., Sahlu, T., Freetly, H. C., & Goetsch, A. L. (2010). Effects of stage of lactation and dietary concentrate level on energy utilization by Alpine dairy goats. Journal of Dairy Science, 93(10), 4818-4828. doi:10.3168/jds.2010-3315United Nations Framework Convention on Climate Change 2015. UN Climate Change Newsroom. Historic Paris agreement on climate change. 195 nations set path to keep temperature rise well below 2 degrees Celsius. Retrieved on 1 July 2018 from http://newsroom.unfccc.int/unfccc-newsroom/finale-cop21/Yan, T., Porter, M. G., & Mayne, C. S. (2009). Prediction of methane emission from beef cattle using data measured in indirect open-circuit respiration calorimeters. Animal, 3(10), 1455-1462. doi:10.1017/s175173110900473

Magnetic and microstructural analysis of palladium nanoparticles with different capping systems

Palladium nanoparticles capped with different protective systems in a size range between 1.2 and 2.4 nm have been obtained by varying the preparation chemical method. Magnetization curves for all the samples show hysteresis loops, evidencing a ferromagnetic or a permanent magnetism in the nanoparticles. The microstructure of the nanoparticles has been analyzed by x-ray absorption and transmission electron microscopy. The nature of the magnetic behavior found for all these Pd nanoparticles (NPs) is different depending on their sizes and structural features and is explained on the basis of two different suggested mechanisms. The particles protected by means of a surfactant (tetralkylammonium salts), present a ferromagnetic order related to the factors increasing the density of states just below the Fermi level. Whereas, when the nanoparticles are stabilized by covalent bonds with protective species (thiol derivatized alkane chains or surface oxidized Pd NPs), the increase of the 4d density of holes, localized by the bonded atoms (S or O), is giving rise to the observed ferromagneticlike behavior