7,463 research outputs found
Luces y sombras del análisis de expresión génica utilizando microarrays. Un ejemplo en cerdo ibérico
Ponencia publicada en ITEA, vol.104La tecnología de los microarrays de expresión es la herramienta ideal para el estudio de patrones de expresión de miles de genes de forma simultánea. Sin embargo existe gran variabilidad de resultados atribuible a los aspectos técnicos y de análisis estadístico. En este trabajo presentamos algunos de los problemas surgidos en el estudio de las diferencias de expresión en hígado de cerdos ibéricos para los tratamientos sexo y alimentación empleando microarrays de Affymetrix. Los datos de expresión normalizados fueron analizados siguiendo dos aproximaciones de la metodología de los modelos mixtos. Para ambos tratamientos las diferencias de expresión detectadas fueron dependientes del modelo de análisis y solo un pequeño número de genes diferencialmente expresados fueron coincidentes en ambas estrategias estadísticas. Algunas de estas diferencias de expresión fueron validadas por PCR cuantitativa. Además identificamos errores de diseño y falta de anotación de las sondas del array. Los resultados de este estudio nos han permitido detectar diferencias de expresión de algunos genes de interés, pero también remarcan la necesidad de realizar estudios complementarios que confirmen las diferencias de expresión reveladas a través de la tecnología de los microarraysLights and darkness of gene expression analysis using microarrays: an example in Iberian pigs Expression microarray technology is the ideal tool for the study of thousands of gene expression patterns simultaneously. However there is a great variability of results attributed to technical and statistical analysis aspects. In this work we present several of the arisen problems of a differential expression study in liver of Iberian pigs under the treatments sex and feeding level using Affymetrix microarray. Normalized expression data were analyzed following two approaches of the mixed model methodology. In both treatments the detected differential expressions were dependent of the statistical model and just a small number of genes were coincident between both statistical strategies. Some of the expression differences were confirmed by quantitative PCR. Besides, we have identified design mistakes and missing annotation of the array probes. The results of this study have allowed us to detect differential expression of interesting genes, but it pointed out the necessity of carrying out complementary studies in order to confirm the differential expressions revealed using microarrays technology
Design and psychometric evaluation of the 'Clinical Communication Self-Efficacy Toolkit'
Nursing students experience difficulties when communicating in clinical practice. Their self-efficacy in clinical communication should be explored as part of their competence assessment before they are exposed to real human interactions in the clinical setting. The aim of this study was to design and psychometrically evaluate a toolkit to comprehensively assess nursing students’ self-efficacy in clinical communication. The study followed an observational cross-sectional design. A sample of 365 nursing students participated in the study. The ‘Clinical Communication Self-Efficacy Toolkit’ (CC-SET) was comprised of three tools: the ‘Patient-Centered Communication Self-efficacy Scale’ (PCC-SES), the ‘Patient clinical Information Exchange and interprofessional communication Self-Efficacy Scale’ (PIE-SES), and the ‘Intrapersonal communication and Self-Reflection Self-Efficacy Scale’ (ISR-SES). The tools’ reliability, validity (content, criterion, and construct) and usability were rigorously tested. The Cronbach’s alpha coefficient of the three tools comprising the CC-SET was very high and demonstrated their excellent reliability (PCC-SES = 0.93; PIE-SES = 0.87; ISR-SES = 0.86). The three tools evidenced to have excellent content validity (scales’ content validity index > 0.95) and very good criterion validity. Construct validity analysis demonstrated that the PCC-SES, PIE-SES, and ISR-SES have a clear and theoretically-congruent structure. The CC-SET is a comprehensive toolkit that allows the assessment of nursing students’ self-efficacy in interpersonal, interprofessional, and intrapersonal communication
Anatomical, histochemical and immunohistochemical characterization of the outflow tract of ray hearts (Rajiformes; Chondrichthyes)
El resumen aparece en el Program & Abstracts of the 11th International Congress of Vertebrate Morphology, Washington DC 2016. Anatomical Record, Volume 299, Special Feature: 264.Recent work has shown that the cardiac outflow tract of sharks and chimaeras does not consist of a single myocardial component, the conus arteriosus, as classically accepted, but two, namely, the myocardial conus arteriosus and the non-myocardial bulbus arteriosus. However, the anatomical composition of the outflow tract of the batoid hearts remains unknown. The present study was designed to fill this gap. The material examined consisted of hearts of two species of rays, namely, the Mediterranean starry ray (Raja asterias) and sandy ray (Leucoraja circularis). They were studied using scanning electron microscopy, and histochemical and inmunohistochemical
techniques. In both species, the outflow tract consists of two components, proximal and distal with regard to the ventricle. The proximal component is the conus arteriosus; it is characterized by the presence of compact
myocardium in its wall and several transverse rows of pocket-shaped valves at its luminal side. Each valve consists of a leaflet and its supporting sinus. Histologically, the leaflet has two fibrosas, inner and outer, and a middle coat, the
spongiosa. The distal component lacks myocardium. Its wall consists of smooth muscle cells, elastic fibers and collagen. Thus, it shows an arterial-like structure. However, it differs from the aorta because it is covered by the epicardium and crossed by coronary arteries. These findings indicate that the distal component is morphologically equivalent to the bulbus arteriosus of sharks and chimaeras. In contrast to foregoing descriptions, the valves of the
first transverse row are distally anchored to the bulbus arteriosus and not to the ventral aorta. Our findings give added support to the notion that presence of a bulbus arteriosus at the arterial pole of the heart is common to all
chondrichtyans, and not an apomorphy of actinopterygians as classically thought.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. CGL2014-52356-P, CEIMAR, BIO 203, FEDE
Experiences of mothers of extremely preterm infants after hospital discharge
The purpose of this study was to describe and understand the experiences of mothers of extremely preterm infants during the first twelve months at home following discharge from a neonatal intensive care unit. A qualitative, interpretative approach using Gadamer's philosophical hermeneutics was carried out. One focus group and fifteen in-depth, semi-structured interviews were conducted twelve months after hospital discharge. Responses were recorded, transcribed and analyzed using computer-assisted qualitative data analysis. The study´s participants were twenty women. The following themes emerged from the data analysis: 1) 'The journey home: the discharge process', which included the sub-themes 'escaping the hospital environment: between desire and fear' and 'preparing parents for hospital discharge: practice and formal support'; and 2) 'The difficulty of living with an extremely preterm infant', including the sub-themes 'the challenge of an unexpected form of childcare', 'overprotection of and bond with a child with special needs' and 'disturbance in the social/familiar setting: when a mother becomes a nurse'. The process of hospital discharge and the first months at home are difficult. The birth and care of an extremely preterm infant affect the mothers' quality of life as well as their family and social life. Practice and early discharge programmes can make the discharge process easier. The knowledge and understanding of the experience of mothers of extremely preterm infants in the first months at home after hospital discharge could help healthcare professionals to develop educational strategies and counselling interventions in accordance with the mothers' needs. [Abstract copyright: Copyright © 2018 Elsevier Inc. All rights reserved.
Control of trace metal distribution and variability in an interdunal wetland
Trace elements are serious pollutants in the natural environment and are of increasing concern due to the adverse effects at global scale. To refine the current understanding of trace metal distribution and variability in natural environments, concentrations of dissolved trace metals (Ag, Al, As, B, Ba, Be, Co, Cr, Cd, Cu, Fe, Hg, Mo, Ni, Pb, Sb, Se, Th,Tl, U, V, Mn, Zn), major ions, inorganic nutrients (NO3, PO4), TOC and stable isotopes of water were determined in water samples from rainwater, seven piezometers and a pond in the coastal Doñana wetland during four sampling campaigns between 2017 and 2019. Results show clear evaporation signatures of stable isotopes in the pond but not in the groundwater. Hydrochemical analyses yield significant, systematic changes in groundwater trace metal and nutrient composition along the flowpath from the dune belt to the pond, controlled by organic matter in the sediments. Whereas major ions reached maximum concentrations in the pond due to evapoconcentration, most trace metals showed highest concentrations at sites with lower redox levels, except for B, As and U, which showed very high concentrations in the pond. Cu, Zn, Ni, Sb and Tl yielded higher median concentrations in rainwater than in most of the groundwater points and in case of Cu and Zn higher even than in surface water which points to an atmospheric input source of these elements. Temporal variability of trace metals was related to lower hydraulic heads after an elongated dry period which led to lower redox levels and higher concentrations of most of the trace elements whereas major ions showed more constant concentration levels. This is of special concern regarding climate change and the predicted higher frequency of prolonged dry periods, which could modify the natural hydrochemical patterns in undisturbed wetlands systemsThis work has been financed by the CLIGRO Project (MICINN, CGL2016-77473-C3-1-R) of the Spanish National Plan for Scientific and Technical Research and Innovation. The infrastructure has been cofinanced by European Research Funds (SE Scientific Infrastructures and Techniques and Equipment 388 2013, IGME13-1E-2113). We are especially grateful for the technical support of Lidia Molano Leno and Daniel Jesus Martinez Suárez. The contracts of Lidia Molano Leno (PEJ-2014-A-68763) and Daniel Jesus Martinez Suárez (PTA2014-09579-I) were financed by the Ministry of Economy, Industry and Competitiveness of Spain (MINECO) and co-financed by the European Investment Bank (EIB) and the European Social Fund (ESF). The contract of Carmen Serrano Hidalgo was funded by the Industrial PhD grant supported by the Autonomous Region of Madrid, Spain (IND2018/AMB-9553). This work is also a contribution to the Andalusian research groups RNM-308 (Group of Hydrogeology) and RNM-126 (Group of water resources), the Lower Guadalquivir Basin convention between the CN IGME CSIC and Confederación Hidrológica del Guadalquivir (CHG) as well as the convention between Pablo de Olavide University and the Guadalquivir River Basin Board (Hydrological monitoring and modeling in Doñana temporary ponds
Design and psychometric analysis of the COVID-19 prevention, recognition and home-management self-efficacy scale
In order to control the spread of COVID-19, people must adopt preventive behaviours that can affect their day-to-day life. People’s self-efficacy to adopt preventive behaviours to avoid COVID-19 contagion and spread should be studied. The aim of this study was to develop and psychometrically test the COVID-19 prevention, detection, and home-management self-efficacy scale (COVID-19-SES). We conducted an observational cross-sectional study. Six-hundred and seventy-eight people participated in the study. Data were collected between March and May 2020. The COVID-19-SES’ validity (content, criterion, and construct), reliability (internal consistency and test-retest reliability), and legibility were studied. The COVID-19-SES’ reliability was high (Cronbach’s alpha = 0.906; intraclass correlation coefficient = 0.754). The COVID-19-SES showed good content validity (scale’s content validity index = 0.92) and good criterion validity when the participants’ results on the COVID-19-SES were compared to their general self-efficacy (r = 0.38; p 0.001). Construct validity analysis revealed that the COVID-19-SES’ three-factor structure explained 52.12% of the variance found and it was congruent with the World Health Organisation’s recommendations to prevent COVID-19 contagion and spread. Legibility analysis showed that the COVID-19-SES is easy to read and understand by laypeople. The COVID-19-SES is a psychometrically robust instrument that allows for a valid and reliable assessment of people’s self-efficacy in preventing, detecting symptoms, and home-managing COVID-19
Estadística Descriptiva y Probabilidad: (Teoría y problemas)
XXXIV, 261 p. ; 24 cm.Libro ElectrónicoÍndice
Bibliografía: p. [256]-258
Manual para alumnos de titulaciones experimentales que proporciona una visión práctica e intuitiva de la estadística descriptiva y el cálculo de probabilidades, campos básicos y fundamentales de la ciencia estadísticaLibro : Español (spa) : 3a. edIndice general
Prólogo XIII
1. Introducción XIII
2. History (Histórico) XV
3. Licencia de Documentación Libre de GNU XVI
4. GNU Free Documentation License XXVI
A Estadística Descriptiva 1
1 Síntesis de la información 7
1. Rese˜na histórica 7
2. La organización de la información 9
3. Representaciones grá?cas 15
4. Medidas centrales 17
5. Medidas de posición 26
6. Medidas de dispersión 27
7. Desigualdad de Tchebychev 31
8. Momentos de la distribución 31
9. Medidas de forma 33
10. Transformaciones 36
11. Análisis exploratorio de datos 37
12. Ejercicios 40
2 Análisis conjunto de variables. 53
1. Distribución conjunta de dos caracteres 53
2. Distribuciones marginales 55
3. Distribuciones condicionadas 55
4. Independencia 60
5. Medidas de dependencia. Coeficientes de relación 61
6. Ejercicios 78
3 Ajuste y regresión bidimensional 89
1. Introducción 89
2. Ajuste. Criterio de los mínimos cuadrados 91
3. Análisis de la bondad del ajuste 97
4. Regresión. Método de regresión a la media 100
5. Análisis de la bondad de la regresión 102
6. Notas y conclusiones 104
7. Ejercicios 105
B Probabilidad 113
4 Teoría de la probabilidad 117
1. Evolución histórica 117
2. Conjuntos. Operaciones 120
3. Algebra de sucesos 122
4. Distintas de?niciones del concepto de probabilidad 126
5. Propiedades de la función de probabilidad 129
6. Probabilidad condicionada. Independencia 131
7. Dependencia e independencia 132
8. Teorema de la probabilidad total. Teorema de Bayes 133
9. Ejercicios 136
5 Variable aleatoria 145
1. Concepto 145
2. Variables discretas y continuas 146
3. Variables unidimensionales 147
4. Variables multidimensionales 161
5. Ejercicios 173
6 Algunos modelos probabilísticos 185
1. Distribución uniforme discreta 185
2. Experimento de Bernouilli 186
3. Distribución hipergeométrica 191
4. Proceso de Poisson 192
5. Distribución uniforme continua 195
6. Distribución normal 197
7. Relación entre binomial, Poisson y normal 200
8. Teorema central del límite 201
9. Distribución gamma 202
10. Distribución beta 203
11. Distribución de Cauchy 204
12. Distribuciones derivadas de la normal 206
13. Distribución de Laplace 210
14. Distribución logística 211
15. Distribución de Pareto 211
16. Algunos modelos multidimensionales 212
17. Ejercicios 215
A Combinatoria 225
1. Introducción 225
2. Variaciones con repetición 225
3. Variaciones 226
4. Permutaciones 226
5. Permutaciones con repetición 226
6. Combinaciones sin repetición 227
7. Combinaciones con repetición 228
8. Ejercicios 228
B Tablas Estadísticas 233
C Bibliografía 25
Andosols of the Canary Islands (X). Vitrandepts. Mineralogical characteristics. Their interpretation and classification
12 páginas, 8 gráficas.Interpretation, classification and mineralogical characteristics of Vitrandepts are
given by the authors.
The soils of this group are typically andosoils, with a littie differenciated profil
developed on very recent vitric pyroclastic materials.
Primary minerals, and volcanic glasses are very abundant in the gross and fine
fractions of this soil.
Secondary minerals are mainly allophane.
Techniques used for mineralogical identifications include X-Ray, Infrared and
electron-Microscope.Peer reviewe
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