667 results on '"P. Arrazola"'
Search Results
202. PR-LncRNA signature regulates glioma cell activity through expression of SOX factors
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Torres-Bayona, Sergio, Aldaz, Paula, Auzmendi-Iriarte, Jaione, Saenz-Antoñanzas, Ander, Garcia, Idoia, Arrazola, Mariano, Gerovska, Daniela, Undabeitia, Jose, Querejeta, Arrate, Egaña, Larraitz, Villanúa, Jorge, Ruiz, Irune, Sarasqueta, Cristina, Urculo, Enrique, Araúzo-Bravo, Marcos J., Huarte, Maite, Samprón, Nicolas, and Matheu, Ander
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- 2018
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203. Familias y escuelas: los diferentes discursos sobre la participación
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Joaquín Giró Miranda, Anna Mata Romeu, Jordi Vallespir Soler, and Begoña Vigo Arrazola
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familias ,escuela ,participación ,educación. ,Social history and conditions. Social problems. Social reform ,HN1-995 ,Sociology (General) ,HM401-1281 - Abstract
Las familias son uno de los pilares que conforman la comunidad educativa. Su participación en la Educación ha ido adquiriendo cada vez una mayor dimensión, reconociéndose no sólo a través de las legislaciones, incluida la propia Constitución española de 1978, sino también con las numerosas y diferentes medidas para lograr esa participación de las familias en la institución escolar. Sin embargo, la participación es un fenómeno complejo que muestra diversos aspectos en la relación familia-escuela, desde los cauces más formales e institucionales (AMPAs, Consejos Escolares, etc.) hasta otros de carácter informal como los movimientos sociales; desde aquellos que son de carácter individual (tutorías) a los de carácter colectivo (proyectos escolares). Además, la participación también depende no sólo del papel y la implicación que adopten las familias, sino del resto de la comunidad educativa, especialmente equipos directivos y docentes, determinantes en este proceso. El presente artículo analiza cómo han evolucionado los discursos sobre la participación partiendo de un trabajo de campo de carácter cualitativo.
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- 2016
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204. Aportaciones de un estudio etnográfico sobre la participación de las familias a la formación crítica del profesorado en una escuela inclusiva
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Begoña Vigo Arrazola, Belén Dieste Gracia, and Allen Thurston
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Education (General) ,L7-991 - Abstract
El artículo que se presenta enfatiza la importancia de la formación crítica del profesorado para una escuela inclusiva a través de la investigación etnográfica. Más específicamente, el objetivo es dar a conocer y explicar cuáles son las aportaciones que percibe el profesorado cuando participa en una investigación etnográfica sobre las relaciones familia-‐escuela. El estudio se lleva a cabo desde la observación participante, entrevistas semi-‐estructuradas, análisis de documentos e interacción virtual en ocho escuelas de la Comunidad Autónoma de Aragón (España). Los resultados muestran cómo los profesores se hacen conscientes de sus prácticas y de su fundamentación teórica en relación con el contexto con el que interactúan. Los procesos de reflexión y el contraste con diferentes formas de acción parecen contribuir al cuestionamiento y a la reconstrucción de sus prácticas. El estudio destaca la importancia de los procesos de interacción que se generan durante la investigación etnográfica y más específicamente a través de la devolución de los informes de investigación para la formación de profesorado.
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- 2016
205. The Pursuit of an Implication for the Logics L3A and L3B
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Hernández-Tello, Alejandro, Arrazola Ramírez, José, and Osorio Galindo, Mauricio
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- 2017
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206. Small GTPases of the Ras and Rho Families Switch on/off Signaling Pathways in Neurodegenerative Diseases
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Alazne Arrazola Sastre, Miriam Luque Montoro, Patricia Gálvez-Martín, Hadriano M Lacerda, Alejandro Lucia, Francisco Llavero, and José Luis Zugaza
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GTPases ,neurodegeneration ,Alzheimer ,Parkinson ,Ras ,Rap ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Small guanosine triphosphatases (GTPases) of the Ras superfamily are key regulators of many key cellular events such as proliferation, differentiation, cell cycle regulation, migration, or apoptosis. To control these biological responses, GTPases activity is regulated by guanine nucleotide exchange factors (GEFs), GTPase activating proteins (GAPs), and in some small GTPases also guanine nucleotide dissociation inhibitors (GDIs). Moreover, small GTPases transduce signals by their downstream effector molecules. Many studies demonstrate that small GTPases of the Ras family are involved in neurodegeneration processes. Here, in this review, we focus on the signaling pathways controlled by these small protein superfamilies that culminate in neurodegenerative pathologies, such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). Specifically, we concentrate on the two most studied families of the Ras superfamily: the Ras and Rho families. We summarize the latest findings of small GTPases of the Ras and Rho families in neurodegeneration in order to highlight these small proteins as potential therapeutic targets capable of slowing down different neurodegenerative diseases.
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- 2020
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207. Quantum-inspired algorithms in practice
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Juan Miguel Arrazola, Alain Delgado, Bhaskar Roy Bardhan, and Seth Lloyd
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Physics ,QC1-999 - Abstract
We study the practical performance of quantum-inspired algorithms for recommendation systems and linear systems of equations. These algorithms were shown to have an exponential asymptotic speedup compared to previously known classical methods for problems involving low-rank matrices, but with complexity bounds that exhibit a hefty polynomial overhead compared to quantum algorithms. This raised the question of whether these methods were actually useful in practice. We conduct a theoretical analysis aimed at identifying their computational bottlenecks, then implement and benchmark the algorithms on a variety of problems, including applications to portfolio optimization and movie recommendations. On the one hand, our analysis reveals that the performance of these algorithms is better than the theoretical complexity bounds would suggest. On the other hand, their performance as seen in our implementation degrades noticeably as the rank and condition number of the input matrix are increased. Overall, our results indicate that quantum-inspired algorithms can perform well in practice provided that stringent conditions are met: low rank, low condition number, and very large dimension of the input matrix. By contrast, practical datasets are often sparse and high-rank, precisely the type that can be handled by quantum algorithms.
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- 2020
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208. Effect of Human Attachment Style on Horse Behaviour and Physiology during Equine-Assisted Activities–A Pilot Study
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Aitor Arrazola and Katrina Merkies
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equine welfare ,therapy horses ,physiological stress ,behavioural stress ,attachment style ,heart rate ,Veterinary medicine ,SF600-1100 ,Zoology ,QL1-991 - Abstract
Equine-assisted activities (EAA) for human well-being and health rely on human–horse interactions for therapeutic effect. At-risk participants with mental and emotional difficulties can show poor social skills and functioning relationships, potentially leading to unsuccessful human–horse interaction in EAA. This study addresses the effect of the attachment style (AS) of at-risk adolescents on horse physiology and behaviour during an equine-facilitated learning (EFL) program. Thirty-three adolescents participated in a 10-week EFL program with nine therapy horses (the same therapy horse per adolescent throughout the program). Adolescent AS was categorized into secure (n = 7), preoccupied (n = 11), dismissing (n = 1), or fearful (n = 12) using an Experiences in Close Relationships – Relationship Structure questionnaire. Horse heart rate (HR) and behaviour (affiliative and avoidance behaviours) in response to adolescents were recorded during grooming and riding. Over time, horses with fearful AS adolescents showed consistently more affiliative behaviours compared to those with preoccupied AS adolescents during grooming, and more constant HR and avoidance behaviours compared to those with secure AS adolescents during riding. These results suggest that a more predictable and less stressful physiological and behavioural response of therapy horses toward participants in EAA with emotional and behavioural difficulties can be mediated by a human insecure attachment style.
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- 2020
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209. Exact simulation of Gaussian boson sampling in polynomial space and exponential time
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Nicolás Quesada and Juan Miguel Arrazola
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Physics ,QC1-999 - Abstract
We introduce an exact classical algorithm for simulating Gaussian boson sampling (GBS). The complexity of the algorithm is exponential in the number of photons detected, which is itself a random variable. For a fixed number of modes, the complexity is in fact equivalent to that of calculating output probabilities, up to constant prefactors. The simulation algorithm can be extended to other models such as GBS with threshold detectors, GBS with displacements, and sampling linear combinations of Gaussian states. In the specific case of encoding non-negative matrices into a GBS device, our method leads to an approximate sampling algorithm with polynomial runtime. We implement the algorithm, making the code publicly available as part of Xanadu's The Walrus library and benchmark its performance on GBS with random Haar interferometers and with encoded Erdős-Renyi graphs.
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- 2020
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210. Teaching Practices and Teachers' Perceptions of Group Creative Practices in Inclusive Rural Schools
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Arrazola, Begoña Vigo and Bozalongo, Juana Soriano
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The central purpose of this paper is to highlight the research in a context where inclusive education is recognised within current global challenges in education. We aim to present different teaching practices and perceptions of teachers from rural schools regarding attention to diversity, before and during a collaborative action that reinforces and develops creative teaching practices. Participant observation, informal conversations and video-recording are the methods that we used. The data show the adoption of relevant group creative teaching practices and the development of inclusive thought. These aspects seem to promote the access to the curriculum of all children. The collaborative work is interpreted as encouraging the professional development. The study is of interest as it shows how the knowledge of creative teaching practices from a collaborative work can be systematised. This paper considers implications for founding research that contributes to the comprehension and development of educational contexts of diversity.
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- 2014
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211. Identification of Cortical and Subcortical Correlates of Cognitive Performance in Multiple Sclerosis Using Voxel-Based Morphometry
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Jordi A. Matías-Guiu, Ana Cortés-Martínez, Paloma Montero, Vanesa Pytel, Teresa Moreno-Ramos, Manuela Jorquera, Miguel Yus, Juan Arrazola, and Jorge Matías-Guiu
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multiple sclerosis ,cognitive impairment ,voxel-based morphometry ,magnetic resonance imaging ,neuropsychological assessment ,memory ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Objective: Cognitive impairment is an important feature in multiple sclerosis (MS) and has been associated to several Magnetic Resonance Imaging (MRI) markers, but especially brain atrophy. However, the relationship between specific neuropsychological tests examining several cognitive functions and brain volumes has been little explored. Furthermore, because MS frequently damage subcortical regions, it may be an interesting model to examine the role of subcortical areas in cognitive functioning. Our aim was to identify correlations between specific brain regions and performance in neuropsychological tests evaluating different cognitive functions in a large series of patients with MS.Methods: A total of 375 patients were evaluated with a comprehensive neuropsychological battery and with MRI. Voxel-based morphometry was conducted to analyse the correlation between cognitive performance and gray matter damage, using Statistical Parametric Mapping with the toolboxes VBM8 and Lesion Segmentation Tool.Results: The following correlations were found: Corsi block-tapping test with right insula; Trail Making Test with caudate nucleus, thalamus, and several cortical regions including the posterior cingulate and inferior frontal gyrus; Symbol Digit Modalities Test with caudate nucleus, thalamus, posterior cingulate, several frontal regions, insula, and cerebellum; Stroop Color and Word Test with caudate nucleus and putamen; Free and Cued Selective Reminding Test and Rey-Osterrieth Complex Figure with thalamus, precuneus, and parahippocampal gyrus; Boston Naming Test with thalamus, caudate nucleus, and hippocampus; semantic verbal fluency with thalamus and phonological verbal fluency with caudate nucleus; and Tower of London test with frontal lobe, caudate nucleus, and posterior cingulate.Conclusion: Our study provides valuable data on the cortical and subcortical basis of cognitive function in MS. Neuropsychological tests mainly assessing attention and executive function showed a stronger association with caudate volume, while tests primarily evaluating memory were more strongly correlated with the thalamus. Other relevant regions were the posterior cingulate/precuneus, which were associated with attentional tasks, and several frontal regions, which were found to be correlated with planning and higher order executive functioning. Furthermore, our study supports the brain vertical organization of cognitive functioning, with the participation of the cortex, thalamus, basal ganglia, and cerebellum.
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- 2018
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212. Spatial and temporal variations of aridity shape dung beetle assemblages towards the Sahara desert
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Indradatta deCastro-Arrazola, Joaquín Hortal, Marco Moretti, and Francisco Sánchez-Piñero
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Aridity ,Water availability ,Beta diversity partitioning ,Environmental filtering ,Resource quality ,Dung beetles ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Background Assemblage responses to environmental gradients are key to understand the general principles behind the assembly and functioning of communities. The spatially and temporally uneven distribution of water availability in drylands creates strong aridity gradients. While the effects of spatial variations of aridity are relatively well known, the influence of the highly-unpredictable seasonal and inter-annual precipitations on dryland communities has been seldom addressed. Aims Here, we study the seasonal and inter-annual responses of dung beetle (Coleoptera, Scarabaeidae) communities to the variations of water availability along a semiarid region of the Mediterranean. Methods We surveyed a 400 km linear transect along a strong aridity gradient from the Mediterranean coast to the Sahara (Eastern Morocco), during four sampling campaigns: two in the wet season and two in the dry season. We measured species richness, abundance and evenness. Variations in community composition between sites, seasons and years were assessed through beta diversity partitioning of dissimiliarity metrics based on species occurrences and abundances. The effects of climate, soil, vegetation and dung availability were evaluated using Spearman-rank correlations, general linear regressions and partial least-squares generalized linear regressions for community structure, and non-metric multi-dimensional scaling, Permutational Analysis of Variance (PERMANOVA) and distance-based RDA variation partitioning for compositional variations. Results Dung beetle abundance and species richness showed large seasonal variations, but remained relatively similar between years. Indeed, aridity and its interaction with season and year were the strongest correlates of variations in species richness and composition. Increasing aridity resulted in decreasing species richness and an ordered replacement of species, namely the substitution of the Mediterranean fauna by desert assemblages dominated by saprophagous and generalist species both in space towards the Sahara and in the dry season. Discussion Our study shows that aridity determines composition in dung beetle communities, filtering species both in space and time. Besides the expected decrease in species richness, such environmental filtering promotes a shift towards generalist and saprophagous species in arid conditions, probably related to changes in resource quality along the transect and through the year. Our results highlight the importance of considering the effects of the highly-unpredictable seasonal and inter-annual variations in precipitation when studying dryland communities.
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- 2018
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213. Awareness and use of electronic cigarettes among youth: evidence from the Global Youth Tobacco Survey 2012 - 2015
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Krishna Mohan Palipudi, Candace Jones, Kyungh Ah Lee, Eugene Pun, Rene Arrazola, and Indu Ahluwalia
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WCTOH ,Diseases of the respiratory system ,RC705-779 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background Globally, evidence on the awareness and use of electronic cigarettes (e-cigarettes) is limited. We examined the awareness and current use of e-cigarettes among male and female students aged 13-15 years old across 16 countries or regions that conducted the Global Youth Tobacco Survey (GYTS). Methods GYTS is a cross-sectional, nationally representative, school-based survey of students aged 13-15 years. Data from the16 countries or regions were used to examine student awareness (ever heard of) and current use (in the past 30 days) of e-cigarettes. Sample sizes across the 16 countries or regions ranged from 962 in Georgia to 5,153 in Paraguay and response rates ranged from 75.4% in Georgia to 99.2% in Sudan. Weighted point estimates and 95% confidence intervals (CI) were calculated and statistically significant differences (p< 0.05) by gender were assessed using a two-sample t-test. Results Awareness of e-cigarettes ranged from 19.6% (95% CI: 16.1-23.6) in Peru to 93.0% (95% CI: 91.4-94.3) in the Moscow region of Russia. Across all sites, only Seychelles and United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) had significantly higher awareness of e-cigarette among boys than girls. Current use of e-cigarettes ranged from 1.6% (95% CI: 1.1-2.5) in Kazakhstan to 15.4% (95% CI: 12.6-18.5) in UNRWA. In Albania, Belize, Macao, Seychelles, and UNRWA, boys had a significantly higher prevalence of current e-cigarette use than girls. Conclusions The findings show that awareness and use of e-cigarettes varies considerably across 16 countries/regions. GYTS is a viable platform to measure tobacco use among youth, including emerging products such as e-cigarettes.
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- 2018
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214. Association of tobacco control policies with cigarette smoking among school age youth 13 to 15 in the Philippines, 2000 - 2015
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Rene A Arrazola, Lauren M Dutra, Indu B Ahluwalia, Andrew B Seidenberg, Ramon Theodore A De Guzman, and Florante Trinidad
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WCTOH ,Diseases of the respiratory system ,RC705-779 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background In 2003, the Philippines passed extensive tobacco control legislation, including minimum legal sales age (MLSA) laws, textual warning labels (TWL), and smoke-free public places (SFPP), and pricing strategies. This study examined the impact of these tobacco control policies on cigarette smoking among Filipino youth 13 to 15 years old who attended school. Methods Data from the Philippines Global Youth Tobacco Surveys were analyzed (2000, 2004, 2007, 2011, and 2015). Sample sizes ranged from 3,708 to 5,919, and response rates from 79.5% to 84.8%. Current cigarette smoking was defined as smoking cigarettes on ≥1 day in the past 30 days. Current use of other tobacco products (OTP) was defined as using tobacco products other than cigarettes on ≥1 day in the past 30 days. Annual average cigarette price was obtained for each year from Euromonitor data, and converted into 2015 Philippine pesos Tobacco control legislation (MLSA, TWL, and SFPP) was coded as all three components in effect (1) or none in effect (0, reference). Logistic regression was used to model the association of tobacco control laws with current youth cigarette smoking, adjusting for cigarette price, age, sex, and current OTP use. Results Tobacco control legislation was associated with declines in current cigarette smoking among youth (AOR: 0.65, p< 0.0001). The price of cigarettes was not significantly associated with current cigarette smoking (AOR: 1.01, p=0.2895], which is likely related to the timing and relatively limited magnitude of price increases during this period. Age, sex, and current OTP use were associated with current cigarette smoking (p< 0.0001). Conclusions The development and implementation of the 2003 tobacco control legislation was associated with decreases in current cigarette smoking among Filipino youth in school. Continued implementation and enforcement of comprehensive, evidence-based tobacco control policies can help reduce tobacco use among youths.
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- 2018
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215. Compartmentalized necroptosis activation in excitotoxicity-induced axonal degeneration: a novel mechanism implicated in neurodegenerative disease pathology
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Macarena S Arrazola and Felipe A Court
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Neurology. Diseases of the nervous system ,RC346-429 - Published
- 2019
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216. Síndrome abdominal agudo debido a quiste infectado del mesenterio
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José Martín Palacios-Acosta, Vanessa Carrasquel-Valecillos, Angélica León-Hernández, Jaén Echávez-del Riego, Fabián Ricardo Castañeda-Bochm, and Daniel Hernández-Arrazola
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síndrome abdominal agudo ,quiste de mesenterio infectado ,resección quirúrgica ,Medicine ,Pediatrics ,RJ1-570 - Abstract
Los quistes del mesenterio son lesiones benignas intrabdominales que crecen a expensas de los vasos linfáticos del intestino; son más frecuentes en el mesenterio ileal y muy raros en la edad pediátrica. El síndrome abdominal agudo en la edad pediátrica es difícil de definir al ser un cuadro de origen múltiple y de presentación clínica muy variada; su síntoma principal es el dolor abdominal agudo, una de las causas que con mayor frecuencia motivan consulta en el Servicio de Urgencias Pediátricas. Los quistes de mesenterio son infrecuentes, se estima que se presentan en uno de cada 100 000 ingresos por síndrome abdominal agudo en pediatría. El estudio de elección para el diagnóstico es el ultrasonido abdominal y el tratamiento óptimo es la resección completa del quiste. Se presenta el caso de una paciente con tumor abdominal ingresada para su estudio. Durante su evolución tuvo datos de irritación peritoneal por lo que se decidió realizar una laparotomía exploradora en la que se encontró un quiste del mesenterio, roto e infectado. Se efectuó hemicolectomía izquierda, lavado de cavidad y colostomía de una sola boca. A los tres meses de operada se hizo la restitución del tránsito intestinal con buenos resultados.
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- 2015
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217. IE-7967. Respuesta a la vacunación frente a SARS-CoV-2 con vacunas de ARNm en los pacientes inmunodeprimidos
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Ramírez, N. Rosillo, primary, de Codes, A. García, additional, Miranda, L.P. Cabrera, additional, de Miguel García, S., additional, Verduguez, E. García, additional, and Martínez, P. Arrazola, additional
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- 2022
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218. IE-7971. Perfil clínico y demográfico de los pacientes candidatos a recibir Evusheld® para la prevención de la COVID-19 grave, en un hospital de tercer nivel
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Verduguez, E. García, primary, Ramírez, N. Rosillo, additional, de Miguel García, S., additional, de Codes, A. García, additional, Miranda, L.P. Cabrera, additional, and Martínez, P. Arrazola, additional
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- 2022
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219. Quantum superiority for verifying NP-complete problems with linear optics
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Arrazola, Juan Miguel, Diamanti, Eleni, and Kerenidis, Iordanis
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- 2018
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220. Measuring progress in tobacco prevention and control: the role of surveillance
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Indu B Ahluwalia, René A Arrazola, and Corinne Graffunder
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Public aspects of medicine ,RA1-1270 - Abstract
Nearly six million people worldwide die from tobacco-attributable causes every year, making tobacco the leading cause of preventable disease and death. If current trends continue, tobacco use is expected to result in one billion deaths by the end of the century, most of these in low- and middle-income countries. Cigarette smoking is the most common form of tobacco use in most countries, and the majority of adult smokers try their first cigarette before the age of 18...
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- 2017
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221. Molecular epidemiology of Mycobacterium tuberculosis complex in Brussels, 2010-2013.
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Christelle Vluggen, Karine Soetaert, Guido Groenen, Maryse Wanlin, Martine Spitaels, Wouter Arrazola de Oñate, Maryse Fauville-Dufaux, Claude Saegerman, and Vanessa Mathys
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Medicine ,Science - Abstract
The tuberculosis (TB) incidence rate in Brussels-Capital Region is 3-fold higher than in Belgium as a whole. Eight years after the realization of initial prospective population-based molecular epidemiology investigations in this Region, a similar study over the period 2010-2013 was conducted. TB strains isolated from 945 patients were submitted to genotyping by standardized 24-locus-MIRU-VNTR typing and spoligotyping. The phylogenetic analysis showed that the LAM (16.7%) and Haarlem (15.7%) branches are the two most prevalent TB lineages circulating in Brussels. Analysis of the MDR subgroup showed an association with Beijing strains (39.9%) and patients native of Eastern Europe (40.7%). Genotyping detected 113 clusters involving 321 patients, giving a recent transmission index of 22.9%. Molecular-guided epidemiological investigations and routine surveillance activities revealed family transmission or social contact for patients distributed over 34 clusters. Most of the patients were foreign-born (75.7%). However, cluster analysis revealed only limited trans-national transmission. Comparison with the previous study shows a stable epidemiological situation except for the mean age difference between Belgian-born and foreign-born patients which has disappeared. This study confirms that molecular epidemiology has become an important determinant for TB control programs. However, sufficient financial means need to be available to perform all required epidemiological investigations.
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- 2017
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222. Influence of oxygen content on the machinability of Ti-6Al-4V alloy
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Sacristan, Irantzu, Garay, Ainhara, Hormaetxe, Exabier, Aperribay, Javier, and Arrazola, Pedro J.
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- 2016
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223. The superior mesenteric artery and the variations of the colic patterns. A new anatomical and radiological classification of the colic arteries
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Gamo, E., Jiménez, C., Pallares, E., Simón, C., Valderrama, F., Sañudo, J. R., and Arrazola, J.
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- 2016
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224. Anatomical variations of the celiac trunk: cadaveric and radiological study
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Marco-Clement, I., Martinez-Barco, A., Ahumada, N., Simon, C., Valderrama, J. M., Sanudo, J., and Arrazola, J.
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- 2016
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225. Rhabdomysarcoma of the penis in a boy. Report of a case
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Palacios Acosta José Martín, Venzor Pérez Isaura Georgina, and Hernández Arrazola Daniel
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Rabdomiosarcoma ,pene ,tumor embrionario ,disuría ,priapismo ,Medicine ,Pediatrics ,RJ1-570 - Abstract
Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue malignant tumor. It is more likely to occur in children under 5 years of age and it is most often found in the head and neck. The presentation in the penis is extremely rare. The embryonic variety is the most common histologic subtype. The RMS of the penis is usually a painless mass. In some cases dysuria and priapism can also be present. Treatment is based on surgical resection, che- motherapy and radiation therapy. We describe a 3 year old boy with a 6 month history of a painless enlargement of the penis due to the presence of a mass. On its dorsal aspect measuring 3 x 3 cm with necrotic and ulcerated areas; it did not affect the urethral meatus. On the CT scan a tumor on the left lateral side of the penile shaft was found, with a diameter of 2.8 x 2.5 x 3.3 cm and a 12 cc volume. Surgical resection of the mass was performed. The histopathologic study reported an embryonal type RMS. The patient was treated with chemotherapeutic agents including ifosfamide and doxorubicin, with a favorable outcome.
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- 2014
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226. Effects of two coatings on the quality of papaya (Carica papaya) variety tainung
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Abraham Miranda, Armando Alvis, and Guillermo Arrazola
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carica papaya ,cassava starc ,acidity ,Agriculture - Abstract
The effect of the application of coatings based on cassava starch and one commercial in the conservation of papaya (Carica papaya) Tainung variety was compared. The coating cassava starch used was prepared with a concentration of 4% p/v; the concentration of the commercial wax was prepared by diluting one part of wax to one part of water at room temperature according to the manufacturer's recommendations. Papayas are stored lying down (stalk parallel to the surface), at room temperature (22°C ± 2°C) and 85% relative humidity for a period of 9 days. In the study of the effect of the wax in papayas, there was only statistically significant (P
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- 2014
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227. Mejores prácticas en gestión de proveedores a nivel mundial, aplicables al sistema de Administración de la Relación con el Proveedor (ARP) de la Jefatura de Operaciones Logísticas (JOL) de la Fuerza Aérea Colombiana (FAC)
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Italo Arrazola Aguado
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Administración ,ARP ,cliente ,proveedor ,relación ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 ,Military Science - Abstract
Dentro de la administración de la cadena de abastecimiento ó Supply Chain Management (SCM), se destaca la gestión de proveedores como una de las actividades más críticas para su establecimiento efectivo. Por lo anterior, el presente artículo busca aproximarse al estado del arte en gestión de proveedores, utilizando como referencia revistas internacionales especializadas en el tema, ofreciendo así una base de referencia en futuras investigaciones relacionadas. En este sentido, se propone un conjunto de alternativas para estructurar un procedimiento general, que permita la adecuada toma de decisiones en cuanto a los proveedores tanto en la Jefatura de Operaciones Logísticas de la Fuerza Aérea Colombiana, como en cualquier organización con el ajuste apropiado.
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- 2014
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228. Continuous-variable quantum neural networks
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Nathan Killoran, Thomas R. Bromley, Juan Miguel Arrazola, Maria Schuld, Nicolás Quesada, and Seth Lloyd
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Physics ,QC1-999 - Abstract
We introduce a general method for building neural networks on quantum computers. The quantum neural network is a variational quantum circuit built in the continuous-variable (CV) architecture, which encodes quantum information in continuous degrees of freedom such as the amplitudes of the electromagnetic field. This circuit contains a layered structure of continuously parameterized gates which is universal for CV quantum computation. Affine transformations and nonlinear activation functions, two key elements in neural networks, are enacted in the quantum network using Gaussian and non-Gaussian gates, respectively. The non-Gaussian gates provide both the nonlinearity and the universality of the model. Due to the structure of the CV model, the CV quantum neural network can encode highly nonlinear transformations while remaining completely unitary. We show how a classical network can be embedded into the quantum formalism and propose quantum versions of various specialized models such as convolutional, recurrent, and residual networks. Finally, we present numerous modeling experiments built with the strawberry fields software library. These experiments, including a classifier for fraud detection, a network which generates tetris images, and a hybrid classical-quantum autoencoder, demonstrate the capability and adaptability of CV quantum neural networks.
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- 2019
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229. Spin-Boson Model as A Simulator of Non-Markovian Multiphoton Jaynes-Cummings Models
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Ricardo Puebla, Giorgio Zicari, Iñigo Arrazola, Enrique Solano, Mauro Paternostro, and Jorge Casanova
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spin-boson model ,Jaynes-Cummings model ,multiphoton processes ,quantum simulation ,Mathematics ,QA1-939 - Abstract
The paradigmatic spin-boson model considers a spin degree of freedom interacting with an environment typically constituted by a continuum of bosonic modes. This ubiquitous model is of relevance in a number of physical systems where, in general, one has neither control over the bosonic modes, nor the ability to tune distinct interaction mechanisms. Despite this apparent lack of control, we present a suitable transformation that approximately maps the spin-boson dynamics into that of a tunable multiphoton Jaynes-Cummings model undergoing dissipation. Interestingly, the latter model describes the coherent interaction between a spin and a single bosonic mode via the simultaneous exchange of n bosons per spin excitation. Resorting to the so-called reaction coordinate method, we identify a relevant collective bosonic mode in the environment, which is then used to generate multiphoton interactions following the proposed theoretical framework. Moreover, we show that spin-boson models featuring structured environments can lead to non-Markovian multiphoton Jaynes-Cummings dynamics. We discuss the validity of the proposed method depending on the parameters and analyse its performance, which is supported by numerical simulations. In this manner, the spin-boson model serves as a good analogue quantum simulator for the inspection and realization of multiphoton Jaynes-Cummings models, as well as the interplay of non-Markovian effects and, thus, as a simulator of light-matter systems with tunable interaction mechanisms.
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- 2019
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230. Prevalence and Psychosocial Correlates of Current Smoking among Adolescent Students in Thailand, 2005
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McKnight-Eily, Lela, Arrazola, Rene, Merritt, Robert, Malarcher, Ann, and Sirichotiratana, Nithat
- Abstract
This article examines the prevalence of current smoking and associated psychosocial correlates and whether these correlates differ by sex among adolescent students in Thailand. Data were analyzed from the Thailand Global Youth Tobacco Survey (GYTS), a school-based, cross-sectional survey conducted in 2005 and completed by Mathayom 1, 2, and 3 (U.S. seventh through ninth grades) students. Weighted prevalence estimates of the percentage of students who were current smokers (smoked on greater than or equal to 1 day during the past 30 days) and noncurrent smokers were calculated for the sample and for each psychosocial variable. Separate logistic regression models were calculated for males and females to examine the independent association of the psychosocial correlates of current smoking. Significant correlates for both males and females included close peer smoking, secondhand smoke exposure, being offered a free cigarette by a tobacco industry representative, and belief that smoking is not harmful. These correlates are examined in the context of comprehensive tobacco control laws in Thailand. (Contains 4 tables.)
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- 2010
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231. Three Measures of Returns to Education: An Illustration for the Case of Spain
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Arrazola, Maria and de Hevia, Jose
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In this article, in a context of wage equations with sample selection, we propose a novel interpretation of the partial effects linked to education as additional measures of returns to education that complement the traditional one, which is directly obtained from the estimation of the wage offer equation. Using European Household Panel data for Spain these partial effects were calculated. The results show that there are incentives in Spain for investing in education not only because it means an increase in wages but also because it raises the probability of obtaining any wage at all.
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- 2008
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232. Gender Differentials in Returns to Education in Spain
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Arrazola, Maria and De Hevia, Jose
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In this article, rates of return to education for men and women have been estimated for the Spanish case, controlling for the biases appearing in the least squares estimation of the basic Mincerian equation. The results show that the returns for women are greater than those for men. The gender differential increases when taking into account the endogeneity of the education and the selection bias, and appears to be specially important for vocational and university studies. The results are consistent with the evolution of the demand for education in Spain in the past two decades. (Contains 5 tables, 2 figures and 12 notes.)
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- 2006
233. White Matter Loss in a Mouse Model of Periventricular Leukomalacia Is Rescued by Trophic Factors
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Pierre Gressens, Alfredo Feria-Velasco, Michael S. Levine, Carlos Cepeda, Brian Chu, Don P. Dejarme, Sandra M. Holley, Payam Bokhoor, Paul M. Zhao, Alana Taniguchi, Alfonso R. Arrazola, Socorro A. R. Barajas, Araceli Espinosa-Jeffrey, and Jean de Vellis
- Subjects
premature birth ,excitotoxicity ,periventricular leukomalacia ,white matter regeneration and repair ,central nervous system repair ,transferrin ,insulin and IGF-1. ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Periventricular leukomalacia (PVL) is the most frequent cause of cerebral palsy and other intellectual disabilities, and currently there is no treatment. In PVL, glutamate excitotoxicity (GME) leads to abnormal oligodendrocytes (OLs), myelin deficiency, and ventriculomegaly. We have previously identified that the combination of transferrin and insulin growth factors (TSC1) promotes endogenous OL regeneration and remyelination in the postnatal and adult rodent brain. Here, we produced a periventricular white matter lesion with a single intracerebral injection of N-methyl-d-aspartate (NMDA). Comparing lesions produced by NMDA alone and those produced by NMDA + TSC1 we found that: NMDA affected survival and reduced migration of OL progenitors (OLPs). In contrast, mice injected with NMDA + TSC1 proliferated twice as much indicating that TSC1 supported regeneration of the OLP population after the insult. Olig2-mRNA expression showed 52% OLP survival in mice receiving a NMDA injection and increased to 78% when TSC1 + NMDA were injected simultaneously and ventricular size was reduced by TSC1. Furthermore, in striatal slices TSC1 reduced the inward currents induced by NMDA in medium-sized spiny neurons, demonstrating neuroprotection. Thus, white matter loss after excitotoxicity can be partially rescued as TSC1 conferred neuroprotection to preexisting OLP and regeneration via OLP proliferation. Furthermore, we showed that early TSC1 administration maximizes neuroprotection.
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- 2013
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234. A tribological characterisation of Ti-48Al-2Cr-2Nb and Ti-6Al-4V alloys with dry, flood, and MQL lubricants.
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Hukkerikar, Abhishek V., Arrazola, Pedro-J., Aristimuño, Patxi, Norgren, Susanne, Morandeau, Antoine, and Joly, Damien
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ALLOYS ,SLIDING wear ,TITANIUM alloys ,FLOOD damage ,CARBIDE cutting tools ,CUTTING tools ,TITANIUM aluminides - Abstract
The development of cutting tools requires the knowledge of tribological phenomena at the tool – workpiece contact area. This knowledge is in dearth particularly for difficult-to-cut alloys like gamma titanium aluminide (gamma – TiAl alloys). Therefore, this article is an attempt to plug the gap and aid the development of cutting tools for gamma – TiAl alloys. To this end, friction, adhesion, and coating wear between AlTiSiN coated cemented carbide tool and Ti-48Al-2Cr-2Nb (Near lamellar), Ti-48Al-2Cr-2Nb (Duplex), and the most used titanium alloy of Ti-6Al-4V (alpha – beta) were experimentally derived. A Pin-on-Cylinder (PoC) tribometer with contact conditions corresponding to commercial machining conditions was used with dry, flood(EML), and two MQL lubricants. Additionally, the heat generated and partitioned between the pin and workpiece was quantified to assess the thermal exposure to the coatings. The results showed that Ti-6Al-4V had approximately 50% higher apparent friction coefficient than the Ti-48Al-2Cr-2Nb alloys. Interestingly, the friction coefficients of Ti-48Al-2Cr-2Nb alloys were nearly consistent across the entire test matrix. Notably, the change in the microstructure from near lamellar to duplex did not elicit any qualitative or quantitative change in the friction profile of Ti-48Al-2Cr-2Nb alloys. The contact pressure proved to be the statistically significant property influencing friction evolution inversely for Ti-6Al-4V alloy and directly for Ti-48Al-2Cr-2Nb alloys. The results showed higher probability of coating wear in dry conditions as opposed to the flood and MQL lubricants. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2023
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235. Optimal Manufacturing Configuration Selection: Sequential Decision Making and Optimization using Reinforcement Learning.
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Torayev, Agajan, Abadia, Jose Joaquin Peralta, Martínez-Arellano, Giovanna, Cuesta, Mikel, Chaplin, Jack C, Larrinaga, Felix, Sanderson, David, Arrazola, Pedro-José, and Ratchev, Svetan
- Abstract
In manufacturing, different costs must be considered when selecting the optimal manufacturing configuration. Costs include manufacturing costs, material costs, labor costs, and overhead costs. Optimal manufacturing configurations are those that minimize production criteria, such as costs, production speed, and flexibility, while still meeting the required production levels and quality standards. To find the optimal manufacturing configuration, manufacturers often use a combination of traditional techniques, e.g., mathematical modeling, simulation, and optimization, to evaluate the tradeoffs between different cost factors and identify configurations that provide the best balance between cost and performance. However, these techniques may require long development and simulation time, and/or may require expert knowledge. This paper presents a method for selecting the optimal manufacturing configuration, focusing on cost optimization, using a reinforcement learning (RL) approach for sequential decision-making. The proposed method involves developing a RL environment, requiring lower development and simulation times than traditional techniques, that captures the incurred costs, recurring costs, production rates, and setup times of manufacturing configurations. The problem is then solved using the Proximal Policy Optimization algorithm to identify the configuration that minimizes costs while still meeting the required production levels and quality standards. The effectiveness of the proposed method is validated through a machining process planning case study with multiple cost factors and production constraints. In particular, the machining process plan was developed for an industry-relevant product prototype. The results show that the proposed method can find solutions that are robust to stochastic noise, providing valuable insights for manufacturers looking to optimize manufacturing operations. [ABSTRACT FROM AUTHOR]
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- 2023
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236. Oportunidades de inclusión en escuelas con alta diversidad cultural. Un estudio etnográfico.
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Vigo-Arrazola, Begoña, Dieste, Belén, Blasco-Serrano, Ana Cristina, and Lasheras-Lalana, Pilar
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HIGH school teachers ,INCLUSIVE education ,SCHOOL size ,EDUCATIONAL change ,RURAL schools - Abstract
Copyright of Revista Española de Sociología is the property of Federacion Espanola de Sociologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2023
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237. Heat-flow determination through inverse identification in drilling of aluminium workpieces with MQL
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Segurajauregui, Unai and Arrazola, Pedro José
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- 2015
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238. Returns to Education in Spain: Some Evidence on the Endogeneity of Schooling
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Arrazola, M., De Hevia, J., Risueno, M., and Sanz, J. F.
- Abstract
In this article, rates of return to education for Spanish male employees are calculated and compared using different methods. We derive rates of return from the estimation of three alternative models of human capital. The rates of return obtained by each of these models are different when they are calculated by least squares. Nevertheless, when the endogeneity of education is considered, the rates of return obtained from each of these models are approximately the same, reaching a value close to 9%. In addition, we compute internal rates of return on investments in education. We find that, on average, social returns are about two points lower than private ones. (Contains 1 figure, 6 tables and 4 notes.)
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- 2003
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239. Health Impact Assessment of a Predicted Air Quality Change by Moving Traffic from an Urban Ring Road into a Tunnel. The Case of Antwerp, Belgium.
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Daan Van Brusselen, Wouter Arrazola de Oñate, Bino Maiheu, Stijn Vranckx, Wouter Lefebvre, Stijn Janssen, Tim S Nawrot, Ben Nemery, and Dirk Avonts
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Medicine ,Science - Abstract
BACKGROUND:The Antwerp ring road has a traffic density of 300,000 vehicles per day and borders the city center. The 'Ringland project' aims to change the current 'open air ring road' into a 'filtered tunneled ring road', putting the entire urban ring road into a tunnel and thus filtering air pollution. We conducted a health impact assessment (HIA) to quantify the possible benefit of a 'filtered tunneled ring road', as compared to the 'open air ring road' scenario, on air quality and its long-term health effects. MATERIALS AND METHODS:We modeled the change in annual ambient PM2.5 and NO2 concentrations by covering 15 kilometers of the Antwerp ring road in high resolution grids using the RIO-IFDM street canyon model. The exposure-response coefficients used were derived from a literature review: all-cause mortality, life expectancy, cardiopulmonary diseases and childhood Forced Vital Capacity development (FVC). RESULTS:Our model predicts changes between -1.5 and +2 μg/m³ in PM2.5 within a 1,500 meter radius around the ring road, for the 'filtered tunneled ring road' scenario as compared to an 'open air ring road'. These estimated annual changes were plotted against the population exposed to these differences. The calculated change of PM2.5 is associated with an expected annual decrease of 21 deaths (95% CI 7 to 41). This corresponds with 11.5 deaths avoided per 100,000 inhabitants (95% CI 3.9-23) in the first 500 meters around the ring road every year. Of 356 schools in a 1,500 meter perimeter around the ring road changes between -10 NO2 and + 0.17 μg/m³ were found, corresponding to FVC improvement of between 3 and 64ml among school-age children. The predicted decline in lung cancer mortality and incidence of acute myocardial infarction were both only 0.1 per 100,000 inhabitants or less. CONCLUSION:The expected change in PM2,5 and NO2 by covering the entire urban ring road in Antwerp is associated with considerable health gains for the approximate 352,000 inhabitants living in a 1,500 meter perimeter around the current open air ring road.
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- 2016
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240. Pathway towards an ideal and sustainable framework agreement for the public procurement of vaccines in Spain: a multi-criteria decision analysis
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Federico Martinón-Torres, A. Rivero Cuadrado, P. Arrazola Martinez, N. Zozaya González, I. Cuesta Esteve, S. Tamames Gómez, B. Alcalá Revilla, J. Villaseca Carmena, A.J. García Rojas, J.R. Chávarri Bravo, Álvaro Hidalgo-Vega, and E. Redondo Margüello
- Subjects
030231 tropical medicine ,Immunology ,award criteria ,Relative weight ,framework agreement ,Framework agreement ,Decision Support Techniques ,Seasonal influenza ,03 medical and health sciences ,0302 clinical medicine ,Procurement ,Influenza, Human ,Humans ,Immunology and Allergy ,030212 general & internal medicine ,Pharmacology ,Actuarial science ,Ideal (set theory) ,Vaccination ,vaccines ,multi-criteria decision analysis ,Multiple-criteria decision analysis ,Weighting ,Influenza Vaccines ,Spain ,public procurement ,Business ,Research Article ,Research Paper ,Decision analysis - Abstract
Objective: To advance the development of an ideal and sustainable framework agreement for the public procurement of vaccines in Spain, and to agree on the desirable award criteria and their relative weight. Methods: A multidisciplinary committee of seven health-care professionals and managers developed a partial multi-criteria decision analysis to determine the award criteria that should be considered and their specific weights for the public procurement of routine vaccines and seasonal influenza vaccines, considering their legal viability. A re-test of the results was carried out. The current situation was analyzed through 118 tender specifications and compared to the ideal framework. Results: Price is the prevailing award criterion for the public procurement of both routine (weighting of 60% versus 40% for all other criteria) and influenza (36% versus 64%) vaccines. Ideally, 22 criteria should be considered for routine vaccines, grouped and weighted into five domains: efficacy (weighting of 29%), economic aspects (27%), vaccine characteristics (22%), presentation form and packaging (13%), and others (9%). Per criteria set, price was the most important criterion (22%), followed by effectiveness (9%), and composition/formulation (7%). Regarding influenza vaccines, 20 criteria were selected, grouped, and weighted: efficacy (29%), economic aspects (25%), vaccine characteristics (20%), presentation form and packaging (16%), and others (11%). Per criteria set, price was also the most relevant criterion (19%), followed by composition/formulation (8%), and effectiveness (8%). Conclusions: Contrary to the current approach, technical award criteria should prevail over economic criteria in an ideal and sustainable framework agreement for the public procurement of vaccines.
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- 2020
241. Cutting Force Prediction in Drilling of Titanium Alloy
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Shoichi TAMURA, Takashi MATSUMURA, and Pedro J. ARRAZOLA
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drilling ,titanium alloy ,cutting force ,simulation ,chip formation ,anisotropy ,nano indentation ,strain hardening ,Engineering machinery, tools, and implements ,TA213-215 ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
Cutting force in drilling of Ti-6Al-4V is studied with simulation based on a predictive model. In the force model, three-dimensional chip flow is made by piling up the orthogonal cuttings in the planes containing the cutting velocities and the chip flow velocities, where the cutting model in each plane is made using the orthogonal cutting data. The chip flow direction is determined to minimize the cutting energy. The cutting force is predicted in the determined chip flow model. The force model is verified in comparison between the predicted and the measured cutting forces. In the rolled titanium alloy, anisotropy is observed in the cutting force. Because the cutting edges rotate in drilling, the cutting force changes periodically with the cutting direction with respect to the rolling direction. Hardness change in subsurface is also measured with a nano indenter. The hardness of the titanium alloy increases around 10 µm underneath the machined surface. Meanwhile, hardness of 0.50% carbon steel does not change. The strain hardening effect is considered by the shear stress on the shear plane in the orthogonal cutting data in the force model.
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- 2012
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242. New distributional records of amphibians and reptiles from northern Oaxaca, México
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Cynthia González, Ángel Brenis, and Teresa Arrazola
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Biology (General) ,QH301-705.5 - Abstract
During 2011 we performed a microregional inventory of amphibians and reptiles from the south-central region of the Papaloapan basin in northern Oaxaca. We recorded one amphibian species previously unknown in the state, and recorded range extensions for two additional amphibian and four reptile species. This increases the known herpetofauna of Oaxaca to 378 species.
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- 2014
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243. Improving surface integrity when drilling CFRPs and Ti-6Al-4V using sustainable lubricated liquid carbon dioxide
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RODRIGUEZ, Iñigo, ARRAZOLA, Pedro José, CUESTA, Mikel, STERLE, Luka, and PUŠAVEC, Franci
- Abstract
In the quest for decreasing fuel consumption and resulting gas emissions in the aeronautic sector, lightweight materials such as Carbon Fiber Reinforced Polymers (CFRPs) and Ti-6Al-4V alloys are being used. These materials, with excellent weight-to-strength ratios, are widely used for structural applications in aircraft manufacturing. To date, several studies have been published showing that the use of metalworking fluids (MWFs), special tool geometries, or advanced machining techniques is required to ensure a surface quality that meets aerospace component standards. Conventional MWFs pose a number of environmental and worker health hazards and also degrade the mechanical properties of CFRPs due to water absorption in the composite. Therefore, a transition to more environmentally friendly cooling/lubrication techniques that prevent moisture problems in the composite is needed. This research shows that lubricated LCO2 is a viable option to improve the quality of drilled CFRP and titanium aerospace components compared to dry machining, while maintaining clean work areas. The results show that the best combination of tool geometry and cooling conditions for machining both materials is drilling with Brad point drills and lubricated LCO2. Drilling under these conditions resulted in a 90 % improvement in fiber pull-out volume compared to dry machined CFRP holes. In addition, a 33 % reduction in burr height and a 15 % improvement in surface roughness were observed compared to dry drilling of titanium.
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- 2023
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244. Caracterización fisicoquímica y fisiológica del proceso de maduración de plátano Hartón (musa AAB Simmonds) en dos sistemas de producción
- Author
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Cayón S Daniel Gerardo, Arrazola P Guillermo Segundo, and Barrera V José Luis
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Plátano, Musa, frutales, propiedades fisicoquímicas, respiración, poscosecha, agricultura orgánica y química, plátano Hartón, Córdoba, Colombia ,Plantains, musa, respiration, postharvest, organic and chemist agriculture ,Agriculture - Abstract
En el Laboratorio de Análisis de Alimentos de la Universidad de Córdoba (Colombia) se realizó la caracterización fisicoquímica y fisiológica del proceso de maduración del plátano Hartón (Musa AAB Simmonds) cultivado en los sistemas de producción orgánico y convencional. Para el estudio se utilizó un diseño completamente al azar con arreglo factorial 2 x 5: dos sistemas de producción y cinco estados de maduración. Los análisis realizados fueron físicos: resistencia, días de maduración; químicos: pH, °Brix, azúcares totales y reductores y almidón; y fisiológicos: tasa de respiración a temperatura ambiente. Los resultados obtenidos mostraron que entre los tratamientos (orgánico y convencional) durante el proceso de maduración se observaron diferencias significativas en las variables resistencia, °Brix, pH, acidez; por el contrario las variables azúcares reductores, azúcares totales y almidón tuvieron un comportamiento similar. El índice de respiración en plátano orgánico alcanzó el pico climatérico a los 14 días, y el convencional a los 7, indicando que el primero presenta un mejor comportamiento poscosecha facilitando su comercialización.
- Published
- 2010
245. Caracterización fisicoquímica y fisiológica del proceso de maduración de plátano Hartón (musa AAB Simmonds) en dos sistemas de producción
- Author
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José Luis Barrera V, Guillermo Segundo Arrazola P, and Daniel Gerardo Cayón S
- Subjects
Plátano ,Musa ,frutales ,propiedades fisicoquímicas ,respiración ,poscosecha ,agricultura orgánica y química ,plátano Hartón ,Córdoba ,Colombia ,Agriculture - Abstract
En el Laboratorio de Análisis de Alimentos de la Universidad de Córdoba (Colombia) se realizó la caracterización fisicoquímica y fisiológica del proceso de maduración del plátano Hartón (Musa AAB Simmonds) cultivado en los sistemas de producción orgánico y convencional. Para el estudio se utilizó un diseño completamente al azar con arreglo factorial 2 x 5: dos sistemas de producción y cinco estados de maduración. Los análisis realizados fueron físicos: resistencia, días de maduración; químicos: pH, °Brix, azúcares totales y reductores y almidón; y fisiológicos: tasa de respiración a temperatura ambiente. Los resultados obtenidos mostraron que entre los tratamientos (orgánico y convencional) durante el proceso de maduración se observaron diferencias significativas en las variables resistencia, °Brix, pH, acidez; por el contrario las variables azúcares reductores, azúcares totales y almidón tuvieron un comportamiento similar. El índice de respiración en plátano orgánico alcanzó el pico climatérico a los 14 días, y el convencional a los 7, indicando que el primero presenta un mejor comportamiento poscosecha facilitando su comercialización.
- Published
- 2010
246. Preparando profesores para la atención a la diversidad: potencialidades y limitaciones de un proyecto de innovación y mejora interdisciplinar
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Begoña Vigo Arrazola, Juana Soriano Bozalongo, and Carmen Julve Moreno
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formación profesorado ,innovación educativa ,interdisciplinariedad ,desarrollo de competencia ,diversidad ,educación inclusiva ,Education ,Education (General) ,L7-991 - Abstract
El trabajo que se presenta afronta el reto de la preparación de los futuros maestros para la atención a la diversidad desde un proceso de investigación en la acción. La investigación sugiere que la formación inicial podría contribuir a la preparación de maestros capaces de ofrecer una enseñanza para todos, sean alumnos con necesidades educativas específicas o sin ellas. El diagnóstico de las percepciones de los estudiantes sobre la atención a la diversidad mostró una concepción fundamentalmente técnica y terapéutica. Con la intención de ampliar dicha concepción se diseñó y desarrolló un plan de acción interdisciplinar. La evaluación posterior reflejaba una comprensión de la atención a la diversidad como la respuesta dirigida a todos los alumnos desde una perspectiva que combina aspectos técnicos y personales.
- Published
- 2010
247. Control nutricional en pacientes de traumatología Nutritional control in orthopedic surgery patients
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S. García Duque, G. Pérez Segura, E. Sanavia Morán, J. R. de Juanes Pardo, M.ª P. Arrazola Martínez, and C. Resines Erasun
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Malnutrición ,Úlceras de presión ,Pacientes ,Hospital ,Traumatología ,Malnutrition ,Patients ,Pressure sores ,Orthopaedic area ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Objetivos: Establecer la incidencia y evolución de malnutrición en una cohorte de pacientes ingresados en un servicio de traumatología. Ámbito: Es un estudio observacional y prospectivo, realizado en un hospital terciario que dispone de Unidad de Nutrición Clínica. Pacientes: Se estudian 107 pacientes (56,1% mujeres, 43,9% hombres, edad 62,1 ± 20,4 años) al ingreso en el Servicio de Traumatología y la evolución en la primera consulta externa de los pacientes intervenidos para colocar una prótesis de cadera o rodilla. Intervenciones: Se realizó una historia clínica, recogida de datos antropométricos y tres tests de cribado nutricional: Mini-Nutritional Assessment (MNA), Malnutrition Universal Screening Tool (MUST) y Valoración Global Subjetiva (VGS). Con ellos se calcula la prevalencia de malnutrición al ingreso, comparando las diferencias entre los métodos y la posible existencia de asociación entre la malnutrición y otros factores, tales como úlceras por presión o dependencia para las actividades de la vida diaria. Resultados: Según el MNA el 22% tiene riesgo de malnutrición, en la VGS es un 24% (un 4% están malnutridos) y en el MUST un 80% presenta alto riesgo de malnutrición. Un 1,7% de los pacientes tienen un Índice de Masa Corporal (IMC) menor que 18,5. Existe una relación significativa entre la malnutrición y estado neuropsicológico (p = 0,001), dependencia para las actividades de la vida diaria (p = 0,002) y entre el MUST de alto y medio riesgo con la aparición de úlceras por presión (p = 0,003). Hay empeoramiento del estado nutricional postquirúrgico con 2 tests: MNA y VGS (p = 0,000). Conclusión: En las condiciones del estudio la prevalencia de malnutrición al ingreso en el Servicio de Traumatología es elevada, los pacientes con cirugía protésica de rodilla y cadera muestran al mes un claro empeoramiento de su estado nutricional, así como una mayor incidencia de úlceras por presión.Objective: To assess the nutritional status of orthopaedic patients. Design: Prospective observation study. Setting: Tertiary hospital, Clinical Nutrition Unit. Patients: 107 patients (56,1% women, 43,9% men, 62,1± 20,4 years) are studied at admission to the orthopaedic unit and it is observed the evolution of orthopaedic surgery patients with hip or knee prosthesis. Material and methods: Medical history, anthropometric data and three nutritional screening tools were considered: Mini-Nutritional Assessment (MNA), Malnutrition Universal Screening Tool (MUST) y Valoración Global Subjetiva (VGS). It was assessed the prevalence of malnutrition in patients on admission to hospital, using different methods and determining if a correlation exists between malnutrition and other factors, such as the development of pressure sores of the dependence in activities of daily living. Results: The risk of malnutrition is 22 and 24/100 patients admitted at hospital, if MNA and SGA are used, respectively (SGA caregorized 4% of the group as "malnourished"). 80% patients are considered to be at high risk of malnutrition using MUST. 1,7% patients presented a Body Mass Index (BMI) lower than 18,5. There is a strong agreement between malnutrition and neropsychological status (p = 0,001), and the dependence in activities of daily living (p = 0,002), and between medium and high risk of malnutrition and the development of pressure sores (p = 0,003). If MNA and SGA (p = 0,000) are used, post-surgical patients presents a deteriorating nutritional status. Conclusions: The prevalence of malnutrition in patients on admission to hospital is elevated. Orthopaedic surgery patients with hip and knee prosthesis presented a deteriorating nutritional status, and a higher incidence of pressure sores in a month.
- Published
- 2008
248. Study and improvement of surgical drill bit geometry for implant site preparation
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Soriano, Josu, Garay, Ainhara, Aristimuño, Patxi, and Arrazola, Pedro J.
- Published
- 2014
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249. Mantenimiento de la cadena del frío para las vacunas: una revisión sistemática Cold chain maintenance in vaccines: a systematic review
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José Ramón de Juanes Pardo, Rosa Villanueva Orbáiz, Pilar Arrazola Martínez, Romana Albaladejo Vicente, Paloma Astasio Arbiza, and Paloma Ortega Molina
- Subjects
Cadena del frío ,Revisión sistemática ,Conocimientos ,Estabilidad de las vacunas ,Cold chain ,Systematic review ,Knowledge ,Vaccine stability ,Public aspects of medicine ,RA1-1270 - Abstract
Objetivo: Los programas de inmunización sistemática dependen en gran medida del correcto mantenimiento y la manipulación de las vacunas que se aplican, es decir, del perfecto mantenimiento de la cadena del frío. Por ello, nos propusimos realizar una revisión sistemática de la literatura médica sobre la cadena del frío y las vacunas, con el objetivo de conocer las prácticas diarias en los puntos de vacunación. Métodos: Se efectuó una búsqueda bibliográfica en las principales bases médicas entre 1990 y 2005. Se incluyeron los estudios que, mediante encuesta y/o inspección a puntos de vacunación, aportaban datos sobre: designación de responsable sanitario, existencia de termómetro de máximas y mínimas, temperatura del frigorífico en el momento de la visita y control y registro de la temperatura. Para todas las variables se calculó la prevalencia media con su intervalo de confianza del 95%. Resultados: Se localizaron 377 artículos, se seleccionaron inicialmente 31 y se incluyeron 13 de ellos. El 72,21% de los puntos de vacunación tenía un responsable de vacunas, pero sólo el 61,43% de ellos conocían el rango óptimo de temperaturas. Por otro lado, el 55% de estos puntos tenía un termómetro de máxima y mínima y sólo el 26,88% realizaba controles y registros de temperaturas al menos una vez al día. Conclusión: En las publicaciones incluidas en el estudio se detectan deficiencias importantes en el mantenimiento de la cadena del frío de las vacunas, que ponen en riesgo la efectividad y la eficiencia de los programas de inmunización.Objetive: Systematic immunization programmes mostly depend on the correct maintenance and manipulation of the vaccines to be used, i.e. perfect maintenance of the cold chain. Therefore, we decided to carry out a systematic review of the literature on the cold chain and vaccines, to identify daily practices in vaccine sites. Methods: A literature search was performed in the main medical databases for documents published between 1990 and 2005, including those performed by means of a survey and/or inspection of vaccine sites that provided the following data: a designated health officer, availability of a thermometer with maximums and minimums, refrigerator temperature at the time of the visit, and temperature control and registration. For all the variables, the mean prevalence was calculated with a 95% confidence interval. Results: Three hundred seventy-seven articles were found; 31 were initially selected and 13 were finally included. In 72.21% of the vaccine points, there was an officer responsible for the vaccines, but only 61.43% knew the optimal temperature range. Fifty-five percent of these points had a thermometer with maximums and minimums and only 26.88% carried out temperature controls and registrations at least once per day. Conclusion: Important shortfalls were detected in cold chain maintenance in all selected articles, jeopardizing the effectiveness and efficiency of immunization programs.
- Published
- 2007
250. Analysis of residual stress and work-hardened profiles on Inconel 718 when face turning with large-nose radius tools
- Author
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Madariaga, A., Esnaola, J. A., Fernandez, E., Arrazola, P. J., Garay, A., and Morel, F.
- Published
- 2014
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