53 research outputs found
Selective area growth of InxGa1-xAs nanowires on HfO2 templates for highly scaled nMOS devices
[EN] The replacement of the strained Si channel in metal-oxide-semiconductor-field-effect-transistors (MOSFETs) with high electron mobility III-V compound semiconductors, particularly InGaAs, is being intensively investigated as an alternative to improve the drive current at low supply voltages in sub-10 nm CMOS applications. As device scaling continues, the reduction of the source and drain contact resistance becomes one of the most difficult challenges to fabricate highly scaled III-V-MOSFETs. In this article, we describe a self-aligned process based on selective molecular beam epitaxial regrowth of InxGa1-xAs (x=0-1) raised source/drain nanowire structures on etched recessed areas of a nanopatterned HfO2 template as a key element to integrate high mobility III-V materials with high-κ dielectrics in three-dimensional device architectures. The interaction of atomic H with the surface of the HfO2 nanopatterns has been investigated by using AFM, ToF-SIMS, and ARXPS. Selective growth has been observed for all values of x between 0 and 1. AFM results show that atomic H lowers the temperature process window for InxGa1-xAs selective growth. HRTEM images have revealed the conformality of the growth and the absence of nanotrench formation near the HfO2 mask edges. InxGa1-xAs alloys grown on H-treated HfO2 patterned substrates exhibit a higher uniformity in chemical composition and full strain relaxation for x≥0.5.This work was financially supported by MINECO under grant No. TEC2016-78433, by CSIC under grant No. 201880E058, and by the H2020 European Institute of Innovation & Technology under grant No. EIT15065 (OPTNEWOPT
Diseño de una férula de muñeca impresa en 3D con soporte para un exoesqueleto de los dedos de la mano.
El presente Trabajo de Fin de Grado pretende llegar a marcar un antes y un después en
la evolución y desarrollo de férulas ortopédicas, un material sanitario que a nivel económico
no se encuentra disponible para un amplio marco de la población y cuyos materiales dificultan
su uso.
Con este proyecto se pretende crear una férula dinámica de muñeca con un amplio
número de funciones para pacientes con problemas de movilidad, cognitivos, posibles fisuras
y, especialmente, en pacientes con rotura de tendones flexores de los dedos de la mano. El
motivo del enfoque centrado en esta última premisa es el elevado porcentaje de operaciones de
tendones causados por cortes en el trabajo manual y es que, a pesar de esto, hoy en día todavía
no hay disponible un sistema de ayuda y rehabilitación postoperatorio específico.
Además, esta férula está al alcance de toda la población gracias a su bajo coste, aporta
gran calidad de comodidad gracias a su elevada ligereza conseguida por medio del uso de
impresión aditiva y tiene un diseño muy sencillo que permite ser usado sin limitación alguna
de conocimientos específicos.
Gracias a su diseño modular se ha conseguido también un producto sostenible, cuyas
piezas pueden ser recicladas por separado y sustituidas de manera individual sin necesidad de
desperdiciar la ortesis completamente en caso de fisuras o roturas.
Cabe destacar que su posibilidad de personalización mejorará la calidad del proceso de
rehabilitación reflejándose, por consiguiente, en una mejora de la calidad de vida del pacient
Dairy Debaryomyces hansenii strains produce the antihypertensive casein-derived peptides LHLPLP and HLPLP
The ability of dairy Debaryomyces hansenii, Kluyveromyces lactis and Kluyveromyces marxianus strains to release the casein-derived antihypertensive sequences RYLGY, AYFYPEL, LHLPLP, HLPLP, VPP and/or IPP was examined. Yeast strains were grown in medium with casein as sole nitrogen source and the yeast casein hydrolysates (CSHs) were analysed by HPLC-MS/MS to search for the six antihypertensive sequences. Only LHLPLP and HLPLP were identified in CSHs and exclusively in D. hansenii Dh1 and Dh14 hydrolysates in which both antihypertensive sequences represented approximately 6 (CSH Dh1) and 10% (CSH Dh14) of total peptide content. In addition, a complete analysis of selected CSHs by HPLC-MS/MS allowed the identification of 35 (Dh1) and 46 (Dh14) additional peptides, which could also contribute to the observed in vitro ACE inhibitory potency of both hydrolysates (Dh1, IC50 = 13.6 ± 1.8 μg/mL; Dh14, IC50 = 17.5 ± 2.1 μg/mL) and might confer them multifunctional properties. Finally casein zymography revealed the presence of at least one extracellular protease with a molecular mass of about 50 kDa. In conclusion, the present study contributes to a better insight into bioactive compounds produced by dairy yeasts and shows the feasibility of D. hansenii strains to produce antihypertensive casein-derived peptides.This work was supported by grants AGL2010-21009 and AGL2011-24643 from ‘Ministerio de Educación y Ciencia – FEDER’, Consolider Ingenio 2010, Fun-C-Food, CSD2007-00063 and RETICS INVICTUS RD12/0014/0004 from ‘Instituto de Salud Carlos III’. A. García-Tejedor and L. Sánchez-Rivera are recipients of predoctoral fellowships from ‘Ministerio de Educación y Ciencia’ (BES-2011-044424) and CSIC (JAE-PreDoc), respectively.Peer reviewe
Linear arrays of InGaAs quantum dots on nanostructured GaAs-on-Si substrates
Linear arrays of high-quality quantum dots (QD) integrated in Si are an ideal platform in exploring the manipulation and transmission of quantum information. Understanding QD self-organization mechanisms on substrates compatible with Si technology is therefore of great practical importance. Here we demonstrate the epitaxial growth of linear arrays of InAs and InGaAs QDs from As2 and In molecular beams on bare and GaAs-coated Si(0 0 1) substrates, patterned by high-resolution laser interference nanolithography. Atomic force microscopy, in combination with high-resolution scanning and transmission electron microscopies, show that these arrays exhibit an improvement in growth selectivity, lateral order and size uniformity of the QDs when a pseudomorphic 1 nm-thick GaAs buffer layer is grown prior to InAs deposition. In addition, preferential nucleation of InxGa1-xAs QDs along the 〈1 1 0〉 -oriented edges of the nanostructured GaAs-on-Si(0 0 1) substrate results from In adatom migration from (1 1 1) to (0 0 1) nanofacets and the erosion of the wetting and buffer layers caused by the Ga-In intermixing at the step edge during the Stranski-Krastanov transition. These are key elements in the formation of linear arrays of coherent QDs, which differ in morphology and structure from those obtained on both GaAs(0 0 1) and Si(0 0 1) planar surface
Theory of strong coupling between quantum emitters and propagating surface plasmons
Under the terms of the Creative Commons Attribution License 3.0 (CC-BY).Here we present the theoretical foundation of the strong coupling phenomenon between quantum emitters and propagating surface plasmons observed in two-dimensional metal surfaces. For that purpose, we develop a quantum framework that accounts for the coherent coupling between emitters and surface plasmons and incorporates the presence of dissipation and dephasing. Our formalism is able to reveal the key physical mechanisms that explain the reported phenomenology and also determine the physical parameters that optimize the strong coupling. A discussion regarding the classical or quantum nature of this phenomenon is also presented. © 2013 American Physical Society.This work was supported by the Spanish MINECO (Contracts No.MAT2011-22997, No.MAT2011-28581-C02, and No. CSD2007-046-NanoLight.es) and CAM (Contract No. S-2009/ESP-1503). A. G.-T. and P. A.-H acknowledge FPU Grants No. AP2008-00101 and No. AP2008-00021, respectively, from the Spanish Ministry of Education. This work has been partially funded by the European Research Council (ERC-2011-AdG Proposal No. 290981).S-2009/ESP-1503/Q&C LIGHTPeer Reviewe
In vivo antihypertensive mechanism of lactoferrin-derived peptides: Reversion of angiotensin I- and angiotensin II-induced hypertension in Wistar rats
Novel peptides with antihypertensive effects in SHR rats have previously been identified in lactoferrin (LF) hydrolysates. To investigate their in vivo antihypertensive mechanism, we have assessed the blood pressure lowering effects of two of these LF-derived peptides (RPYL and DPYKLRP) in Wistar rats subjected to either angiotensin I- or angiotensin II-induced hypertension. Blood pressure was measured by the tail-cuff method, hypertension was induced by subcutaneous infusion of angiotensins, and then captopril, valsartan or LF-derived peptides orally administered. Angiotensin I- and angiotensin II-induced hypertension were reversed by captopril and valsartan, respectively. RPYL and DPYKLRP reversed angiotensin I-induced hypertension, while DPYKLRP but not RPYL produced a modest reversion of angiotensin II-elicited hypertension. Neither RPYL nor DPYKLRP modified normotension. Thus, in vivo ACE inhibition is involved in the antihypertensive effects of LF-derived peptides like RPYL and DPYKLRP, while inhibition of AT1 receptor-mediated vasoconstriction plays a less relevant role.This work was supported by grant AGL2010-21009 from ‘Ministerio de Educación y Ciencia – FEDER’, Consolider Ingenio 2010, Fun-C-Food, CSD2007-00063 and RETICS INVICTUS RD12/0014/0004 from ‘Instituto de Salud Carlos III’. A. García-Tejedor is recipient of a predoctoral fellowship from ‘Ministerio de Educación y Ciencia’ (BES-2011-044424).Peer reviewe
Phytotherapy in pregnancy and lactation: benefit or risk? Review of the literature
INTRODUCCIÓN: Durante el embarazo el organismo de la mujer sufre cambios temporales con aparición de estructuras orgánicas nuevas como la placenta. Cualquier sustancia, natural o sintética, que pueda producir una alteración de los procesos fisiológicos propios de esta etapa están contraindicados. OBJETIVO: Dar a conocer los productos de origen vegetal utilizados habitualmente en el embarazo y la lactancia y evaluar su eficacia y seguridad. MATERIAL Y MÉTODOS: Revisión integradora de la literatura en las bases de datos Cochrane Library, Cinahl, Medline, Cuiden, Cuidatge, Bireme, Enfispo y buscadores de la red. Tras la lectura de los artículos, se realizó una valoración crítica, síntesis e interpretación para llegar a conclusiones de todos los estudios seleccionados. RESULTADOS: El uso de plantas medicinales en el embarazo es habitual, encontrándose el jengibre y la equinácea entre las más utilizadas. En cuanto a la etapa del embarazo de mayor consumo, se identifica el primer trimestre. El mayor porcentaje de las gestantes utiliza las plantas sin indicación médica. En cuanto a la eficacia: la equinácea es eficaz para el resfriado común e infecciones vaginales, el arándano rojo para la infección urinaria, la raíz de jengibre y la ipecacuana tienen acción antiemética, la hierba de San Juan es eficaz en la depresión postparto, la valeriana para combatir el nerviosismo y el aceite de onagra para inducir el parto. El nivel de seguridad varía según la planta por lo que se recomienda un control por parte del profesional sanitario. DISCUSIÓN Y CONCLUSIONES: De forma general las mujeres no están educadas en cuanto a la influencia que ejerce el estilo de vida en las primeras células embrionarias. El uso de productos fitoterápicos puede ser eficaz para ayudar a solucionar muchos de los problemas del embarazo pero es necesario ver la relación riesgo-efectividad. Por eso, antes, durante y después del embarazo o lactancia materna las mujeres que desean tomar preparados herbarios, deben consultar con su matrona u otro profesional sanitario bien informado al respecto, porque muchos de los efectos de las plantas sobre los fetos y la leche materna son desconocidos.INTRODUCTION: During pregnancy, women´s body suffers from temporary changes with new organic structures such as placenta. Any subtance, natural or sintetic which may alter physiological proceses on this own state are contraindicated. OBJECTIVE: Dara know the plant products commonly used in pregnancy and lactation and assess their effectiveness and safety. MATERIAL AND METHODS: Integrative review of literature in the databases Cochrane Library, CINAHL, Medline, Cuiden, Cuidatge, Medicine , ENFISPO and Web searches. After reading the articles, critical appraisal, synthesis and interpretation was performed to reach conclusions of all selected studies. RESULTS: The use of medicinal plants during pregnancy is frequent, being ginger and echinace some of the most used ones. Regarding the stage of pregnancy with higher consumption, it is the first term. The highest percentage of pregnant women use plants without any medical advices. As for effectiveness: Echinacea is effective for the common cold and vaginal infections, cranberry for urinary infection, ginger root and ipecac have antiemetic action, St. John's wort is effective in postpartum depression, valerian to combat nervousness and evening primrose oil to induce labor. The security level varies depending on the plant so a control by the health care professional is recommended. DISCUSION AND CONCLUSIONS: Generally, women are not aware of the influence of their life style on the first embryonic cells. The use of herbal products can be effective in helping to solve many of the problems of pregnancy but you need to see the risk-effectiveness. Because of that, previously, during an after pregnancy or breastfeeding, those women who want to take herbalist products, should first consult a midwife or another medical professional who is well-informed about it, because many of the effect of plants on fetus and breastmilk are still unknown
An antihypertensive lactoferrin hydrolysate inhibits angiotensin I-converting enzyme, modifies expression of hypertension-related genes and enhances nitric oxide production in cultured human endothelial cells
This study was aimed to explore whether an antihypertensive lactoferrin hydrolysate (LFH) can inhibit angiotensin I-converting enzyme (ACE) activity and modify the expression of genes related to hypertension in human umbilical vein endothelial cells (HUVEC). LFH induced significant inhibition of ACE activity but it did not affect ACE mRNA levels after 24 h of exposure. LFH treatment significantly affected the expression of genes encoding for proteins involved in nitric oxide pathway such as soluble guanylate cyclase 1 α3 subunit (GUCY1A3; 4.42-fold increase) and nitric oxide synthase trafficking (NOSTRIN; 2.45-fold decrease). Furthermore, expression of the PTGS2/COX-2 gene encoding prostaglandin-endoperoxide synthase 2 a key component of prostaglandin synthesis was significantly increased (2.23-fold). Moreover, NOSTRIN mRNA downregulation was consistent with reduced NOSTRIN protein expression and increased NO production observed in HUVEC. The present study reveals the complexity of the effects exerted by LFH opening avenues for the better understanding of its antihypertensive effects.This work was supported by grant AGL2010-21009 from ‘Ministerio de Educación y Ciencia – FEDER’, Consolider Ingenio 2010, Fun-C-Food, CSD2007-00063 and RETICS INVICTUS RD12/0014/0004 from ‘Instituto de Salud Carlos III’. A. García-Tejedor is recipient of a predoctoral fellowship from ‘Ministerio de Educación y Ciencia’ (BES-2011-044424).Peer reviewe
Novel Antihypertensive Lactoferrin-Derived Peptides Produced by Kluyveromyces marxianus: Gastrointestinal Stability Profile and In Vivo Angiotensin I-Converting Enzyme (ACE) Inhibition
Novel antihypertensive peptides released by Kluyveromyces marxianus from bovine lactoferrin (LF) have been identified. K. marxianus LF permeate was fractionated by semipreparative high performance liquid chromatography and 35 peptides contained in the angiotensin I-converting enzyme (ACE)-inhibitory fractions were identified by using an ion trap mass spectrometer. On the basis of peptide abundance and common structural features, six peptides were chemically synthesized. Four of them (DPYKLRP, PYKLRP, YKLRP, and GILRP) exerted in vitro inhibitory effects on ACE activity and effectively decreased systolic blood pressure after oral administration to spontaneously hypertensive rats (SHRs). Stability against gastrointestinal enzymes suggested that the sequence LRP could contribute to the in vivo effects of parental peptides. Finally, there were reductions in circulating ACE activity and angiotensin II level in SHRs after either DPYKLRP or LRP intake, thus confirming ACE inhibition as the in vivo mechanism for their antihypertensive effect.This work was supported by grant AGL2010–21009 from ‘Ministerio de Educación y Ciencia - FEDER’, Consolider Ingenio 2010, Fun-C-Food, CSD2007–00063 and RETICS INVICTUS RD12/0014/0004 from ‘Instituto de Salud Carlos III’. A.G.-T. is the recipient of a predoctoral fellowship from ‘Ministerio de Educación y Ciencia’ (BES-2011–044424).Peer reviewe
Reconstrucción de variables climáticas en el sector oriental de la Cordillera Ibérica mediante técnicas dendrocronológicas
Los periodos húmedos y las sequías, siendo éstas últimas un fenómeno frecuente en el ámbito mediterráneo, han generado consecuencias en los sistemas naturales e impactos en las actividades socioeconómicas. Para poder pronosticar en el futuro estos sucesos, pudiendo prevenir a la sociedad y adaptar sus actividades ante estos sucesos, se ha determinado la necesidad de conocer mejor la evolución del pasado. En este trabajo se presenta una reconstrucción del índice de precipitación y evapotranspiración estandarizado (SPEI) en el barrano de los Lores (Mosqueruela, Teruel). Para ello se han utilizado 30 muestras de madera con las que se ha podido correlacionar el crecimiento de los árboles con el clima, pudiendo elaborar una correcta sincronización, medición y función de transferencia con la que realizar una reconstrucción final de 340 años. De este modo, se ha podido observar la presencia de 12 años extremos húmedos y 2 años extremos secos, junto con 5 periodos húmedos y 6 periodos secos especialmente marcados. Toda esta información se ha relacionado con otras reconstrucciones generadas en el Sistema Ibérico, coincidiendo en los años principalmente más extremos y visualizando de este modo los patrones sinópticos atmosféricos comunes que han surgido sobre el territorio
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