179 research outputs found
Nonlinear time-domain macromodeling of OTA circuits
The authors present an accurate nonlinear macromodel of the operational transconductance amplifier (OTA) which is suitable for the transient simulation of OTA-based CMOS analog integrated circuits. As compared to device-level OTA models, the proposed macromodel is advantageous in terms of CPU time. Also, in circuits with many OTAs, it does not have the problems of convergence that the device-level MODEL has. All the macromodel parameters can be calculated from measurements made at the OTA terminals. Experimental results from a 3-ÎŒm CMOS OTA prototype as well as simulation results from device-level models are included and compared to simulation results from the macromodel
Trispyrazolylborate Ligands Supported on Vinyl Addition Polynorbornenes and Their Copper Derivatives as Recyclable Catalysts
Polynorbornenes prepared by vinyl addition poly- merization and bearing pendant alkenyl groups serve as skeletons to support trispyrazolylborate ligands (Tpx) built at those alkenyl sites. Reaction with CuI in acetonitrile led to VA-PNBâTpxCu(NCMe) (VA-PBN = vinyl addition polynorbor- nene) with a 0.8â1.4 mmol incorporation of Cu per gram of polymer. The presence of tetracoordinated copper(I) ions was been assessed by FTIR studies on the corresponding VA-PNB-TpxCu(CO) adducts, in agreement with those on discrete TpxCu(CO). The new materials were employed as heteroge- neous catalysts in several carbene- and nitrene-transfer reac- tions, showing a behavior similar to that of the homogene- ous counterparts but also being recycled several times main- taining a high degree of activity and selectivity. This is the first example of supported Tpx ligands onto polymeric sup- ports with catalytic applications.MINECO (CTQ2017-82893-C2-1-R, CTQ2016-80913-P and Red Intecat CTQ2016-81923-REDC)Junta de Castilla y LeĂłn (VA051P17, VA062G18)European Union (CHAOS COST ACTION CA-15106)
Mitochondrial DNA (mtDNA) haplogroups influence the progression of knee osteoarthritis: data from the Osteoarthritis Initiative (OAI)
[Abstract] OBJECTIVE:
To evaluate the influence of the mtDNA haplogroups on knee osteoarthritis progression in Osteoarthritis Initiative (OAI) participants through longitudinal data from radiographs and magnetic resonance imaging (MRI).
METHODS:
Four-year knee osteoarthritis progression was analyzed as increase in Kellgren and Lawrence (KL) grade, in addition to increase in OARSI atlas grade for joint space narrowing (JSN), osteophytes and subchondral sclerosis in the tibia medial compartment of 891 Caucasian individuals from the progression subcohort. The influence of the haplogroups on the rate of structural progression was also assessed as the four-year change in minimum joint space width (mJSW in millimetres) in both knees of (nâ=â216) patients with baseline unilateral medial-tibiofemoral JSN. Quantitative cartilage measures from longitudinal MRI data were those related to cartilage thickness and volume with a 24 month follow-up period (nâ=â381).
RESULTS:
During the four-year follow-up period, knee OA patients with the haplogroup T showed the lowest increase in KL grade (Hazard Risk [HR]â=â0.499; 95% Confidence Interval [CI]: 0.261-0.819; p<0.05) as well as the lowest cumulative probability of progression for JSN (HRâ=â0.547; 95% CI: 0.280-0.900; p<0.05), osteophytes (HRâ=â0.573; 95% CI: 0.304-0.893; p<0.05) and subchondral sclerosis (HRâ=â0.549; 95% CI: 0.295-0.884; p<0.05). They also showed the lowest decline in mJSW (standardized response means (SRM)â=â-0.39; pâ=â0.037) in those knees without baseline medial JSN (no-JSN knees). Normalized cartilage volume loss was significantly lower in patients carrying the haplogroup T at medial tibia femoral (SRMâ=â-0.33; pâ=â0.023) and central medial femoral (SRMâ=â-0.27; pâ=â0.031) compartments. Cartilage thickness loss was significantly lower in carriers of haplogroup T at central medial tibia-femoral (SRMâ=â-0.42; pâ=â0.011), medial tibia femoral (SRMâ=â-0.32; pâ=â0.018), medial tibia anterior (SRMâ=â+0.31; pâ=â0.013) and central medial femoral (SRMâ=â-0.19; pâ=â0.013) compartments.
CONCLUSIONS:
Mitochondrial genome seems to play a role in the progression of knee osteoarthritis. mtDNA variation could improve identification of patients predisposed to faster or severe progression of the disease.Instituto de Salud Carlos III; CIBERCB06/01/0040Instituto de Salud Carlos III; PI 08/2028Ministerio de Ciencia e Innovación (España); PLE2009-014
The effect of cold waves on mortality in urban and rural areas of Madrid
While many studies analyze the effect of extreme thermal events on health, little has been written about the effects of extreme cold on mortality. This scarcity of papers is particularly relevant when we search studies about extreme cold on the health of rural population. Therefore, we tried to analyze the effect of cold waves on urban areas and rural areas from Madrid and to test whether differentiated effects exist between both population classes. For this purpose, we analyzed data from the municipalities with over 10,000 inhabitants for the period from January 1, 2000 through December 31, 2013. Municipalities were classified as urban or rural (Eurostat), and they were grouped into similar climatological zones: Urban Metropolitan Centre (UMC), Rural Northern Mountains (RNM), Rural Centre (RC) and Southern Rural (SR). The dependent variable was the daily mortality rate due to natural causes per million inhabitants (CIE-X: A00-R99) that occurred between the months of November and March for the period. The independent variable was minimum daily temperature (ÂșC) (Tmin). Social and demographic contextual variables were used, including: populationâ>âage 64 (%), deprivation index and housing indicators. The analysis was carried out in three phases: (1) determination of the threshold temperature (Tthreshold) which defines the cold waves; (2) determination of the relative risk (RR) for cold waves using Poisson linear regression (GLM); and (3) using GLM of the binomial family, Odds Ratios (OR) were calculated to analyze the relationship between the frequency of the appearance of cold waves and the socioeconomic variables.The authors gratefully acknowledge the grants for projects ENPY376/18; ENPY470/19 and ENPY 107/18 from the Carlos III Institute of Health
Uso de tecnologĂas TIC para implicar al alumnado en el proceso de enseñanza-aprendizaje en IngenierĂa
Este artĂculo es el resultado de un proyecto de innovaciĂłn docente aplicado a dos asignaturas del Ărea de IngenierĂa HidrĂĄulica en el Grado de IngenierĂa Civil y Recursos EnergĂ©ticos y Mineros. En este proyecto se persigue incentivar al alumnado como parte activa del proceso de enseñanza-aprendizaje a travĂ©s de herramientas TICs cada vez mĂĄs familiares para ellos como son: empleo de recursos audiovisuales, prĂĄcticas virtuales apoyadas en material fotogrĂĄfico y vĂdeos, realizaciĂłn de cuestionarios vĂa moodle o a travĂ©s de aplicaciĂłn mĂłvil, resoluciĂłn de problemas mediante hojas de cĂĄlculo, entre otras.This paper is the result of a âTeaching Innovation Projectâ applied to two subjects taught by the Hydraulic Engineering Knowledge Area in the Civil and Mining Engineering degree. The project aims to encourage the student to play an active role in the teaching-learning process through ICT tools. These tools increasingly used and welcome by the student are: audiovisual resources, virtual practices supported by photos and videos, questionnaires through the virtual platform or via a mobile application, solve the activities with spreadsheet among other activities
LA VILLA BAJOIMPERIAL Y TARDO ANTIGUA DE LOS MONDRAGONES (GRANADA)
The villa of Mondragones is an unpublished archaeological site located in the north of Granada, very closed to the ancient Municipium Florentinum Iliberritanum, and it is part of its ager. It is a very vast settlement where itâs easy to identify the principal elements of a villa, as the domus, the pars fructuaria and pars rustica. The site has been occupied from the f irst century A.D. to the seventh century A.D., that let us analyze the changes occurred from the fourth century A.D. in the hinterland of Eliberri.La villa de los Mondragones es un yacimiento arqueolĂłgico inĂ©dito que se localiza en la zona norte de Granada, muy cerca del antiguo Municipium Florentinum Iliberritanum, formando parte de su ager. Se trata de un asentamiento de gran extensiĂłn en el que se identif ican los elementos fundamentales de una villa, como son la domus, la pars fructuaria y elementos de la pars rustica. Tiene un periodo de ocupaciĂłn que va desde su fundaciĂłn en el siglo I d.C. hasta el siglo VII d.C. lo cual permite analizar los cambios producidos a partir del siglo IV d.C. y las transformaciones de la AntigĂŒedad TardĂa en el territorio mĂĄs prĂłximo a la ciudad de Eliberri
DNA polymerase λ, a novel DNA repair enzyme in human cells
DNA polymerase lambda (pol λ) is a novel family X DNA polymerase that has been suggested to play a role in meiotic recombination and DNA repair. The recent demonstration of an intrinsic 5âČ-deoxyribose-5-phosphate lyase activity in pol A supports a function of this enzyme in base excision repair. However, the biochemical properties of the polymerization activity of this enzyme are still largely unknown. We have cloned and purified human pol A to homogeneity in a soluble and active form, and we present here a biochemical description of its polymerization features. In support of a role in DNA repair, pol λ inserts nucleotides in a DNA template-dependent manner and is processive in small gaps containing a 5âČ-phosphate group. These properties, together with its nucleotide insertion fidelity parameters and lack of proofreading activity, indicate that pol A is a novel ÎČ-like DNA polymerase. However, the high affinity of pol λ for dNTPs (37-fold over pol ÎČ) is consistent with its possible involvement in DNA transactions occurring under low cellular levels of dNTPs. This suggests that, despite their similarities, pol ÎČ and pol λ have nonredundant in vivo function
Mitochondrial DNA haplogroups influence the risk of incident knee osteoarthritis in OAI and CHECK cohorts: a meta-analysis and functional study
Extended report[Abstract] Objective To evaluate the influence of the mitochondrial DNA (mtDNA) haplogroups in the risk of incident knee osteoarthritis (OA) and to explain the functional consequences of this association to identify potential diagnostic biomarkers and therapeutic targets.
Methods Two prospective cohorts contributed participants. The osteoarthritis initiative (OAI) included 2579 subjects of the incidence subcohort, and the cohort hip and cohort knee (CHECK) included 635, both with 8-year follow-up. The analysis included the association of mtDNA haplogroups with the rate of incident knee OA in subjects from both cohorts followed by a subsequent meta-analysis. Transmitochondrial cybrids harbouring haplogroup J or H were constructed to detect differences between them in relation to physiological features including specific mitochondrial metabolic parameters, reactive oxygen species production, oxidative stress and apoptosis.
Results Compared with H, the haplogroup J associates with decreased risk of incident knee OA in subjects from OAI (HR=0.680; 95% CI 0.470 to 0.968; p<0.05) and CHECK (HR=0.728; 95% CI 0.469 to 0.998; p<0.05). The subsequent meta-analysis including 3214 cases showed that the haplogroup J associates with a lower risk of incident knee OA (HR=0.702; 95% CI 0.541 to 0.912; p=0.008). J cybrids show a lower free radical production, higher cell survival under oxidative stress conditions, lower grade of apoptosis as well as lower expression of the mitochondrially related pro-apoptotic gene BCL2 binding component 3 (BBC3). In addition, J cybrids also show a lower mitochondrial respiration and glycolysis leading to decreased ATP production.
Conclusions The physiological effects of the haplogroup J are beneficial to have a lower rate of incident knee OA over time. Potential drugs to treat OA could focus on emulating the mitochondrial behaviour of this haplogroup.Instituto de Salud Carlos III; CIBERCB06/01/0040-SpainInstituto de Salud Carlos III; RETIC-RIER-RD12/0009/0018Instituto de Salud Carlos III; PI14/01254Instituto de Salud Carlos III; CP12/0319
Informe del sismo de Lorca del 11 de mayo de 2011
En la reciente historia sĂsmica de España, desde el terremoto de 1956 en Albolote
(Granada) con once muertos y el de 1969 al SW del Cabo San Vicente con cuatro, el
terremoto de Lorca de 11 de mayo de 2011 (magnitud 5.1) ha vuelto a ser
especialmente importante por haber ocasionado nueve vĂctimas mortales. El
movimiento sĂsmico, localizado muy prĂłximo a la ciudad de Lorca, ha afectado
directamente a mĂĄs de 90.000 personas, que han sufrido sus consecuencias al
registrarse con una intensidad de grado VII en la escala europea EMS, lo que ha
motivado daños notables en las viviendas.
El presente informe trata de reflejar las caracterĂsticas del terremoto y de su serie de
réplicas, recogiendo los trabajos que han desarrollado diferentes equipos de
investigaciĂłn, tanto previos al terremoto como posteriores. El estudio describe los
aspectos cientĂficos y tĂ©cnicos de mayor interĂ©s, desde la historia sĂsmica de la zona
hasta el comportamiento de las edificaciones de la ciudad de Lorca. Asimismo, se
acompaña de un encuadre geolĂłgico de la zona y de las caracterĂsticas de la falla de
Alhama de Murcia, responsable de la ocurrencia del terremoto.
Como consecuencia de los terremotos que hubo la misma zona en el año 2005,
precedidos por un apreciable nivel de actividad sĂsmica en los años 1999 y 2002, la
regiĂłn de Murcia fue objeto del proyecto RISMUR, cofinanciado por el Instituto
GeogrĂĄfico Nacional y en el que participaron los redactores de este informe. Algunos
de los aspectos de este proyecto, en concreto los relativos a la peligrosidad sĂsmica
han sido incluidos, incidiendo en los resultados que se obtuvieron en la ciudad de
Lorca.
El informe va acompañado al final de una serie de conclusiones en relación con cada
uno de los temas tratados, resaltando aquellos aspectos que se deberĂĄn tener en
cuenta en futuros proyectos, a fin de mejorar por un lado el conocimiento de la
sismicidad y peligrosidad sĂsmica y por otro para la adecuaciĂłn de la normativa
sismorresistente.Peer reviewe
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