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Hydroxyapatite (HA) is a material widely used by the medical community due to its Ca/P ratio is comparable to the Ca/P ratio of bones and teeth, which promotes osteoinduction and osteoconduction processes when in contact with bone tissue, either as volume piece or coating. This work focuses on studying the quality of the commercial HA powder MKnano-#MKN-HXAP-S12 µm, after processing, to obtain sintered compact discs with suitable physical and chemical characteristics for implants applications. The HA powder was processed through calcination, grinding, pressing and sintering to evaluate the effect of such as procedures in the compacts dics quality. The raw powder was characterized by laser diffraction, SEM, XRF, XRD, TGA and DSC while the characteristics of the obtained compact discs were determined by dilatometry and XRD to identify the sintering temperature range, constituent phases, the amorphous content and the crystallinity degree, parameters that allow determining their suitability for implants applications. Although, it was not possible to obtain sintered compacts with the suitable chemical composition and without fractures, this work allowed to identify the parameters that determine the suitability of a HA powder to obtain sintered compacts for medical applications, as well as the characterization protocol that allows the evaluation of such parameters. © Published under licence by IOP Publishing Ltd.

Hydroxyapatite (HA) is a material widely used by the medical community due to its Ca/P ratio is comparable to the Ca/P ratio of bones and teeth, which promotes osteoinduction and osteoconduction processes when in contact with bone tissue, either as volume piece or coating. This work focuses on studying the quality of the commercial HA powder MKnano-#MKN-HXAP-S12 µm, after processing, to obtain sintered compact discs with suitable physical and chemical characteristics for implants applications. The HA powder was processed through calcination, grinding, pressing and sintering to evaluate the effect of such as procedures in the compacts dics quality. The raw powder was characterized by laser diffraction, SEM, XRF, XRD, TGA and DSC while the characteristics of the obtained compact discs were determined by dilatometry and XRD to identify the sintering temperature range, constituent phases, the amorphous content and the crystallinity degree, parameters that allow determining their suitability for implants applications. Although, it was not possible to obtain sintered compacts with the suitable chemical composition and without fractures, this work allowed to identify the parameters that determine the suitability of a HA powder to obtain sintered compacts for medical applications, as well as the characterization protocol that allows the evaluation of such parameters. © Published under licence by IOP Publishing Ltd.

Hydroxyapatite (HA) is a material widely used by the medical community due to its Ca/P ratio is comparable to the Ca/P ratio of bones and teeth, which promotes osteoinduction and osteoconduction processes when in contact with bone tissue, either as volume piece or coating. This work focuses on studying the quality of the commercial HA powder MKnano-#MKN-HXAP-S12 µm, after processing, to obtain sintered compact discs with suitable physical and chemical characteristics for implants applications. The HA powder was processed through calcination, grinding, pressing and sintering to evaluate the effect of such as procedures in the compacts dics quality. The raw powder was characterized by laser diffraction, SEM, XRF, XRD, TGA and DSC while the characteristics of the obtained compact discs were determined by dilatometry and XRD to identify the sintering temperature range, constituent phases, the amorphous content and the crystallinity degree, parameters that allow determining their suitability for implants applications. Although, it was not possible to obtain sintered compacts with the suitable chemical composition and without fractures, this work allowed to identify the parameters that determine the suitability of a HA powder to obtain sintered compacts for medical applications, as well as the characterization protocol that allows the evaluation of such parameters. © Published under licence by IOP Publishing Ltd.

Alumina (Al2O3) thin films were deposited on Si (100) by Magnetron Sputtering in reactive conditions between an aluminium target and oxygen 99.99% pure. The plasma was formed employing Argon with an R.F power of 100 W, the dwelling time was 3 hours. 4 samples were produced with temperatures between 350 and 400 °C in the substrate by using an oxygen flow of 2 and 8 sccm, the remaining parameters of the process were fixed. The coatings and substrates were characterized using Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and Energy Dispersive Spectroscopy (EDS) in order to compare their properties before and after deposition. The films thicknesses were between 47 and 70 nm. The results show that at high oxygen flow the alumina structure prevails in the coatings while at lower oxygen flow only aluminum is deposited in the coatings. It was shown that the temperature increases grain size and roughness while decreasing the thicknesses of the coatings. © Published under licence by IOP Publishing Ltd.

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Al2O3 with 13 and 45wt.% TiO2 microsized powders (6-22 and 13-41µm for each chemical composition) were used as raw materials to coat AISI 1040 steel by atmospheric plasma spraying. The mechanical properties of the coatings were measured by micro-indentation tests, and drilling experiments were carried out using high speed steel (HSS) rotary drill bits of various diameters and varying the load on the drill bits. In order to reduce the effect of the wear on the bit, a new bit was used for each test. According to the results, the drilling test is proposed as a method of determining the mechanical properties of these coatings from the correlation found between coating hardness and drilling resistance. © 2012 Elsevier B.V.

In chronic lymphocytic leukemia (CLL) the level of minimal residual disease (MRD) after therapy is an independent predictor of outcome. Given the increasing number of new agents being explored for CLL therapy, using MRD as a surrogate could greatly reduce the time necessary to assess their efficacy. In this European Research Initiative on CLL (ERIC) project we have identified and validated a flow-cytometric approach to reliably quantitate CLL cells to the level of 0.0010% (10(-5)). The assay comprises a core panel of six markers (i.e. CD19, CD20, CD5, CD43, CD79b and CD81) with a component specification independent of instrument and reagents, which can be locally re-validated using normal peripheral blood. This method is directly comparable to previous ERIC-designed assays and also provides a backbone for investigation of new markers. A parallel analysis of high-throughput sequencing using the ClonoSEQ assay showed good concordance with flow cytometry results at the 0.010% (10(-4)) level, the MRD threshold defined in the 2008 International Workshop on CLL guidelines, but it also provides good linearity to a detection limit of 1 in a million (10(-6)). The combination of both technologies would permit a highly sensitive approach to MRD detection while providing a reproducible and broadly accessible method to quantify residual disease and optimize treatment in CLL.

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In chronic lymphocytic leukemia (CLL) the level of minimal residual disease (MRD) after therapy is an independent predictor of outcome. Given the increasing number of new agents being explored for CLL therapy, using MRD as a surrogate could greatly reduce the time necessary to assess their efficacy. In this European Research Initiative on CLL (ERIC) project we have identified and validated a flow-cytometric approach to reliably quantitate CLL cells to the level of 0.0010% (10(-5)). The assay comprises a core panel of six markers (i.e. CD19, CD20, CD5, CD43, CD79b and CD81) with a component specification independent of instrument and reagents, which can be locally re-validated using normal peripheral blood. This method is directly comparable to previous ERIC-designed assays and also provides a backbone for investigation of new markers. A parallel analysis of high-throughput sequencing using the ClonoSEQ assay showed good concordance with flow cytometry results at the 0.010% (10(-4)) level, the MRD threshold defined in the 2008 International Workshop on CLL guidelines, but it also provides good linearity to a detection limit of 1 in a million (10(-6)). The combination of both technologies would permit a highly sensitive approach to MRD detection while providing a reproducible and broadly accessible method to quantify residual disease and optimize treatment in CLL.

Nowadays, with the increase of elderly population and related health problems, knee and hip joint prosthesis are being widely used worldwide. However, failure of these invasive devices occurs in a high percentage thus demanding the revision of the chirurgical procedure. Within the reasons of failure, microbial infections, either hospital or subsequently-acquired, contribute in high number to the statistics. Staphylococcus epidermidis (S. epidermidis) has emerged as one of the major nosocomial pathogens associated with these infections. Silver has a historic performance in medicine due to its potent antimicrobial activity, with a broad-spectrum on the activity of different types of microorganisms. Consequently, the main goal of this work was to produce Ag-ZrCN coatings with antimicrobial activity, for the surface modification of hip prostheses. Thin films of ZrCN with several silver concentrations were deposited onto stainless steel 316 L, by DC reactive magnetron sputtering, using two targets, Zr and Zr with silver pellets (Zr + Ag target), in an atmosphere containing Ar, C2H2 and N2. The antimicrobial activity of the modified surfaces was tested against S. epidermidis and the influence of an activation step of silver was assessed by testing samples after immersion in a 5% (w/v) NaClO solution for 5 min. The activation procedure revealed to be essential for the antimicrobial activity, as observed by the presence of an inhibition halo on the surface with 11 at.% of Ag. The morphology analysis of the surface before and after the activation procedure revealed differences in silver distribution indicating segregation/diffusion of the metallic element to the film's surface. Thus, the results indicate that the silver activation step is responsible for an antimicrobial effect of the coatings, due to silver oxidation and silver ion release.

This study combines a water system analysis of a coastal aquifer in western Mexico that is subject to seawater intrusion, where a hydrogeological characterisation of the area is given, with numerical modelling of the controlling processes and parameters as an instrument to provide a better understanding of the water system. The MOCDENS3D code is used in this study to model density dependent groundwater flow. The hydrodynamic behaviour of the coastal aquifer is similar to an island aquifer, where the freshwater lens “floats” on top of higher salinity water bodies, in this case saline from the sea and hypersaline from the lagoon. The freshwater lens varies in thickness according to the wet and dry seasons. This causes the freshwater lens to be in a delicate equilibrium between recharge and discharge of freshwater. High evaporation rates result in brine concentrations in the lagoon which enter the system in the form of saline fingers that are density driven. The numerical results provide a relatively close approximation to the density distribution that underlies the sand bar where field measurements were carried out. The results are highly sensitive to changes in the precipitation and evapotranspiration rates, with small changes leading to different concentration configurations, particularly in the freshwater lens. Results also demonstrate that a numerical model of this scale can be useful as a conceptual tool to understand the controlling factors that determine groundwater flow. The scenarios of climate change indicate that hydraulic heads will increase due to sea level rise and decrease due to longer periods of drought, and that the volume of fresh groundwater in the freshwater lens is sensitive to both of these scenarios. However, further research is necessary to provide more spatially extensive data that can be used to answer several of the uncertainties evidenced by this model.

The aim of this study was to verify the possible physical and chemical changes that may occur on the surface of Ag-TiCN coatings after exposure to the culture media used in microbiological and cytotoxic assays, respectively tryptic soy broth (TSB) and Dulbecco's modified eagle's medium (DMEM). After sample immersion for 24 h in the media, analyses were performed by glow discharge optical emission spectroscopy discharge radiation (GDOES), Rutherford backscattering spectroscopy (RBS) and x-ray photoelectron spectroscopy (XPS). The results of GDOES profile, RBS and XPS spectra, of samples immersed in TSB, demonstrated the formation of a thin layer of carbon, oxygen and nitrogen that could be due to the presence of proteins in TSB. After 24 h of immersion in DMEM, the results showed the formation of a thin layer of calcium phosphates on the surface, since the coatings displayed a highly oxidized surface in which calcium and phosphorus were detected. All these results suggested that the formation of a layer on the coating surface prevented the release of silver ions in concentrations that allow antibacterial activity.

Colombian mining is usually done without any proper scientific methodology, and therefore, without knowing if there is more potential for the mineral resource being mined. For a scientific insight, this work presents the analysis of clay mineral characterization and nano-pores evaluation. The samples were obtained from the Arcabuco zone, a region located in Boyacá-Colombia. The techniques used to identify the minerals, the crystal structure, the chemical composition and the thermal properties were X-ray Diffraction (XRD), Scanning Electron Microscopy and Energy-dispersive X-ray Spectroscopy (SEM - EDX), Thermogravimetry and Differential Thermal Analysis (TG-DTA), Mössbauer Spectroscopy (MS), and finally Positron Annihilation Spectroscopy. The XRD data were analyzed by means of the Rietveld refinement method, finding phases like Montmorillonite, Quartz, Illite and Kaolinite. These phases were corroborated using the characterization techniques previously described. Positron annihilation data were used to detect and evaluate the size of the nano-pores and to correlate them with the behavior of the dehydration and hydration kinetics in these measurements obtained by TG-DTA.

Contains fulltext : 129968.pdf (publisher's version ) (Open Access), Brain computer interface systems use brain signals to enable the control of external devices, such as: wheelchairs, communicators, neuro-prosthesis, among others; in people with severe motor disabilities. In this study two young men with motor disabilities were trained to learn how to control a brain computer interface (BCI) using the P300 evoked potential recorded by electroencephalography (EEG). This interface enables the verbal communication through a stimulation matrix (4x3 rows and columns) that contains the picture of current football players and a sound related to each one which reproduced the name of them. Initially, we did the preparation stage that allowed the users to learn how to control the BCI. After this, the real probes were performed in two stages: the training tests and the online tests, where the participant could select the icons that he wanted through his brain signals. The average percentages of success for each participant were: 95% and 85%, respectively. The average time for an icon selection was 36 seconds (i.e.1.67 letters/minute).

Background/aimsBipolar disorder (BP) is a severe psychiatric illness, characterised by alternating episodes of depression and mania, which ranks among the top ten causes of morbidity and life-long disability world-wide. We have previously performed a whole-genome linkage scan on 6 pedigrees segregating severe BP from the well-characterised population isolate of Antioquia, Colombia. We recently collected genotypes for the same set of 382 autosomal microsatellite markers in 9 additional Antioquian BP pedigrees. Here, we report the analysis of the combined pedigree set.MethodsLinkage analysis using both parametric and nonparametric approaches was conducted for 3 different diagnostic models: severe BP only (BPI); mood disorders (BPI, BPII and major depression); and psychosis (operationally defined by the occurrence of at least 1 episode of hallucinations and/or delusions).Results and conclusionFor BPI only, the most interesting result was obtained for chromosome 7p21.1-p22.2 under a recessive model of inheritance (heterogeneity LOD score = 2.80), a region that had previously been linked to BP in a study on Portuguese Island families. For both BPI and mood disorders, nonparametric analyses identified a locus on chromosome 12ct-q14 (nonparametric linkage = 2.55 and 2.35, respectively). This locus has not previously been reported as a candidate region for BP. Additional candidate regions were found on chromosomes 1p22-31 (mood disorders) and 21q21-22 (BPI), 2 loci that have repeatedly been implicated in BP susceptibility. Linkage analysis of psychosis as a phenotype identified candidate regions on chromosomes 2q24-31 and 16p12-q12. The finding on chromosome 16p is noteworthy because the same locus has been implicated by genome-wide association analyses of BP.

The purpose of the study is to describe the experience of suffering among informal care takers of patients with cancer-pain and non-cancer pain at three health institutions of Medellín-Colombia. It is a qualitative study of phenomenological type. The sample consisted of 16 care takers of patients who suffered cancer-pain and non-cancer pain. The information was gathered through a semi-structured interview, the level of suffering was quantified through the emotional thermometer as a complementing element to the qualitative approach. The data obtained were analyzed through categories and profiles previously defined which showed the most common meaning, level and factors of suffering among the interviewed care takers. The results showed that the majority of care takers experienced high levels of suffering. They reported feelings of sadness and satisfaction in a contradictory manner. In the cognitive realm, they associated suffering with pain and the good execution of their activity; in the behavioral field, they expressed that suffering was related to the difficulty in controling the patient’s physical symptoms, and with the deferral of their own life activities. In conclusion, the psychological support received by the care takers was perceived as a protecting factor to reduce suffering; the type of pain was related to the experience of suffering and the care taker’s role, who were mostly female care takers of patients with cancer pain. The interviewed care takers were atrisk of presenting Burnout due to the multiple demands inherent to their role., A pesquisa visa descrever a experiência de sofrimentos dos cuidadores informais de pacientes com oncológica e não oncológica em três instituições de saúde em Medellín. É uma pesquisa qualitativa de tipo fenomenológico. A amostra esteve conformada por 16 cuidadores de pacientes com dor oncológica e não oncológica. A informação foi coletada através de uma entrevista semi-estruturada e se quantificou o nível de sofrimento por meio do termômetro emocional como complemento à abordagem qualitativa. Os dados obtidos foram analisados mediante categorias e perfis previamente definidos que dão conta do significado, do nível e dos fatores de sofrimento mais comuns nos cuidadores entrevistados. Os resultados evidenciaram que os níveis de sofrimento na maioria dos cuidadores eram altos. Também, observaram-se sentimentos contraditórios de tristeza e satisfação. No âmbito cognitivo, associaram o sofrimento com dor e com ofato de fazerem bem sua atividade; e na parte comportamental apontaram que o sofrimento estava ligado à dificuldade para controlar os sintomas físicos do paciente, e com o adiamento de atividades próprias de sua vida. Em conclusão, o apoio psicossocial recebido pelos cuidadores não foi percebido como fator protetor para a diminuição do sofrimento; o tipo de dor estava relacionado com a experiência de sofrimento e o papel de cuidadores, que eram maiormente pacientes com dor oncológica. Os cuidadores entrevistados estavam em risco de apresentar Burnout por causa das múltiples demandas de sua função., El objetivo de la investigación es describir la experiencia de sufrimiento de los cuidadores informales de pacientes con dolor oncológico y no oncológico de tres instituciones de salud de Medellín. Es una investigación cualitativa de tipo fenomenológico. La muestra estuvo conformada por 16 cuidadores de pacientes con dolor oncológico y no oncológico. La información se recolectó a través de una entrevista semiestructurada y se cuantificó el nivel de sufrimiento por medio del termómetro emocional como complemento al enfoque cualitativo. Los datos obtenidos se analizaron por medio de categorías y perfiles previamente definidos, lo cual dio cuenta del significado, el nivel y los factores de sufrimiento más comunes en los cuidadores entrevistados. Los resultados evidenciaron que la mayoría de los cuidadores experimentaron altos niveles de sufrimiento. Reportaron sentimientos de tristeza y satisfacción contradictoriamente. En la esfera cognitiva, asociaron el sufrimiento con dolor y con el hacer bien su actividad; y en el área conductual, refirieron que el sufrimiento se relacionaba con la dificultad para el control de os síntomas físicos del paciente, y con el aplazamiento de actividades propias de su vida. En conclusión, el apoyo psicosocial recibido por los cuidadores no fue percibido como factor protector para la disminución del sufrimiento; el tipo de dolor estaba relacionado con la experiencia de sufrimiento y el rol de cuidadores, quienes en su mayoría eran mujeres cuidadoras de pacientes con dolor oncológico. Los cuidadores entrevistados estaban en riesgo de presentar Burnout debido a las múltiples demandas propias de su rol.

El propósito de esta investigación fue reconocer e interpretar las representaciones sociales a partir de los discursos construidos por los ciudadanos de unas zonas referenciales de la localidad de chapinero en la ciudad de Bogotá (Zona G, Zona T y parque de la 93), que por su significado permitirían servir de base para elaborar Marketing Urbano. Para la recolección de esta información se utilizó la técnica de entrevista a profundidad, realizada a dos ciudadanos los cuales conocían y frecuentaban las zonas. Al analizar los discursos, los resultados encontrados muestran que la apropiación, el sentido de pertenencia y el significado de los espacios, permiten que éstos sean representativos a lo largo del tiempo de manera individual y colectiva para los sujetos.

La propuesta metodológica de la ecología como campo de la diversidad, complejidad e interconectividad debe ayudar a responder a problemas de intersección de distintas disciplinas, entre ellas la historia ecológica o ambiental, la economía ecológica y, el tema que nos ocupa, la ecología política (Ecopol). Este artículo presenta algunos temas relevantes de la literatura producida, entre ellos, los trabajos con impacto epistemológico; emancipación así como los que apuntan a la fundamentación juridicopolítica de la cuestión ecológica, resaltando contribuciones de autores latinoamericanos. Plantea temas centrales de investigación, tales como gobermentalidad; seguridad biodiversidad y justicia ambiental. La Ecopol debe ser una reflexión política en torno a las relaciones de poder y problemas de conocimiento sobre la construcción social, la distribución y el control sobre la naturaleza.

Objective: to understand the couple¿s process to achieve fertility control. Methodology: a quantitative survey carried in Medellín, Colombia. Seventeen men and twenty three women between 20 and 35 years, of different social stratus and educational levels, with more than a year marital relationship were interviewed. The methodology is supported on grounded theory. Results: the findings show how according to feminine and masculine significants the couples assume a fixed position facing reproduction. This deal with is a decision-taking process between risky and safe decisions. Accordingly some are continually ¿searching security¿ to avoid unwanted children while others are continually ¿taking risks¿ about an unwanted pregnancy. Discussion: the couple¿s strategies to face reproduction are tainted by their interpretation of the gender norms. The security looking couples assume gender norms in a flexible way whereas the risk-taking couples have a rigid perception of the gender norms and the power relationships. Conclusions: the conclusion is that the masculine and feminine significants about how males and females should be influences their reproductive behavior. The couples¿ contexts and significants about reproduction define their behavior in birth control. Accordingly it is fundamental to know the context and perceptions about reproduction if we want to provide education able to transform behavior., Objetivo: comprender el proceso que hombres y mujeres viven como pareja para realizar el control de la fertilidad. Metodología: estudio cualitativo realizado en Medellín, Colombia, entre los años 2002 y 2005. Se entrevistaron 17 hombres y 23 mujeres entre 20 y 35 años, de diferentes estratos sociales y niveles educativos, con una relación de pareja no inferior a un año. Metodológicamente se apoya en la teoría fundamentada. Resultados: los hallazgos muestran cómo las parejas, con base en las significaciones de lo femenino y lo masculino, asumen una determinada posición frente a cómo enfrentar la reproducción. Dicho afrontamiento es un proceso que se mueve entre decisiones que van desde correr riesgos hasta estar totalmente seguros. Según esto, algunos(as) están continuamente ¿buscando la seguridad¿ para no tener hijos(as) no deseados; otros, están permanentemente ¿corriendo el riesgo¿ de una gestación no deseada. Discusión: las estrategias utilizadas por las parejas para enfrentar la reproducción están mediadas por la interpretación que hacen de las normas de género; aquellas que buscan la seguridad asumen las normas de género de una manera flexible, las parejas que corren riesgos las asumen de forma rígida así como las relaciones de poder. Conclusiones: se concluye que las significaciones de hombres y mujeres sobre el deber ser masculino y femenino, influyen en los comportamientos reproductivos. Los contextos y las significaciones que las parejas tienen de la reproducción, definen sus comportamientos en el control de la reproducción. Y conocer los contextos y las percepciones que tienen sobre la reproducción es fundamental si se quiere brindar una educación que transforme comportamientos.

Descriptive transversal study to identify the opportunities given by the nursing team to familiar attendants echo participate in the care of the hospitalized relatives. It¿s an answer to the continuous questions from the academic practice and the personal experiences with hospitalized relatives. One structured interview soar realized to 265 attendants of hospitalized persons in institutions of the second level of attention; it searched the socio-demographic aspects of the patient and the attendant, and which are were indicated, explained and supported by the nursing team; the education given to attendants is another factor orbed to persons included in the sample. Those hospitalized persons with attendants, 54% are female, in the age group of 64-77 years, with low scholarly. The first cause of morbidity corresponds to gastro-intestinal problems, followed by cardio-vascular diseases. The attendants are usually the daughters with a median age of 45 years. The tasks more frequently realized by attendants are those related to subsistence, such as bathing and feeding, others as lecture, music and games are realized only by 10% of the attendants; conversation is the task more frequently realized. The interaction of the nursing team with the attendants is almost inexistent for all the task of caring explored in this study, except for the indication and support given for the bath. The practical nurse has more interaction with the attendants. It¿s remarkable the absence of the professional nurse. Education is mostly given by the professional nurse, but just to 11% of the hospitalized persons. It¿s only penetrating in the mystery of care and searching deep in the human and cultural character of care, how we can transcend a respectful and trustful relation with the clients, families and the social environment., Estudio descriptivo transversal para identificar las oportunidades de participación en el cuidado que el equipo de enfermería propicia a los acompañantes del paciente hospitalizado. Nace como respuesta a los interrogantes continuos desde la practica académica y por vivencias personales con familiares hospitalizados. Se realiza una entrevista estructurada a 265 acompañantes de instituciones de salud del segundo nivel de complejidad, en las cuales se indagó por aspectos socio-demográficos de los usuarios y acompañantes, las acciones de cuidado que ejecuta el acompañante y cuáles son indicados, explicados y apoyados por el equipo de enfermería. La educación que éste proporciona al acompañante es otro asunto que se cuestionó en la muestra. De los usuarios con acompañante el 54% son de sexo femenino, los de mayor tiempo de compañía están en el grupo etáreo de 64 a 77 años y se caracterizan por un nivel bajo de escolaridad. Como primera causa de morbilidad está los problemas gastrointestinales; seguidos de los problemas cardiovasculares. Las personas que más acompañan son los hijos de sexo femenino, con promedio de edad de 45 años. Los cuidados que más realizan los acompañantes son los relacionados con la subsistencia, como el baño y la alimentación, acciones como la lectura, el juego y la música son realizados sólo en el 10 % en contraste con la conversación que es una de las acciones que más se realizan. La interacción del equipo de enfermería con el acompañante es mínima para casi todos los cuidados explorados en el estudio, se presentó la mayor interacción en la indicación, explicación y apoyo del baño. La auxiliar de enfermería es quien más interactúa con el acompañante en estas categorías; sobresale la poca interacción del profesional en enfermería. La educación, es impartida por el profesional de enfermería en mayor proporción; sin embargo, sólo se brinda al 11% del total de usuarios hospitalizados. Solo sí se penetra en el misterio del cuidado y se aborda profunda

Nitrogen implantation in titanium has been carried out at 125 and 100 keV with nominal doses between 4 × 1017 and 8 × 1017 ions cm-2, respectively. Surface characterization by Auger electron spectroscopy has demonstrated the presence of a TiN layer near the surface, which increased the surface hardness from 300 to 1000 HV. From the corrosion viewpoint, N-implantation has little effect in saline solutions, although a slight increase of corrosion resistance could be achieved. In acid solutions, impedance data show that the low frequency impedance of the implanted alloy was higher than that for pure titanium. The capacitance value was similar for all the implanted materials, being somewhat below the value found for unimplanted titanium. These data lead us to conclude that resistance is conferred by the surface formation of titanium nitride, rather than a surface oxide layer. No differences have been found in the corrosion behaviour of samples processed at doses of 4 × 1017 and 8 × 1017 ions cm-2.

A modification is proposed to the convergence-confinement method (CCM) which directly introduces the effect of depth and the shape of the tunnel cross-section in the determination of the radial displacement of the tunnel. A series of shape functions were determined, based on results obtained in three-dimensional simulations, which approximate the radial displacement at points situated on the perimeter of the cross-section of the tunnel, taking into account several cross-sections at different distances from the working face. The advantage of the method is that, should the cross-section of the tunnel or its depth be modified, it is not necessary to perform new numerical simulations in order to apply the CCM. It will only be necessary to use the calculated shape functions. The CCM can be used in the analysis and design of the support elements in a precise and significantly more rapid way., A modification is proposed to the convergence-confinement method (CCM) which directly introduces the effect of depth and the shape of the tunnel cross-section in the determination of the radial displacement of the tunnel. A series of shape functions were determined, based on results obtained in three-dimensional simulations, which approximate the radial displacement at points situated on the perimeter of the cross-section of the tunnel, taking into account several cross-sections at different distances from the working face. The advantage of the method is that, should the cross-section of the tunnel or its depth be modified, it is not necessary to perform new numerical simulations in order to apply the CCM. It will only be necessary to use the calculated shape functions. The CCM can be used in the analysis and design of the support elements in a precise and significantly more rapid way.

A geometrical method is described for identifying pyramidal and non-pyramidal key blocks in discontinuous rock masses for tunnel excavation. The non-pyramidal key blocks are determined by geometrical dislocation in relation to the advance in the direction of the tunnel axis. The blocks are parameterised with the advance and the block with the maximum volume is calculated. Non-pyramidal, pentahedral blocks larger than the pyramidal tetrahedral blocks may occur, depending on discontinuity planes. The method was used to develop a computer program for selecting the orientation in which a tunnel must be excavated so as to generate the minimum number of large-volume key blocks., A geometrical method is described for identifying pyramidal and non-pyramidal key blocks in discontinuous rock masses for tunnel excavation. The non-pyramidal key blocks are determined by geometrical dislocation in relation to the advance in the direction of the tunnel axis. The blocks are parameterised with the advance and the block with the maximum volume is calculated. Non-pyramidal, pentahedral blocks larger than the pyramidal tetrahedral blocks may occur, depending on discontinuity planes. The method was used to develop a computer program for selecting the orientation in which a tunnel must be excavated so as to generate the minimum number of large-volume key blocks.

The key block method for analysing rock mass stability is reviewed and an analysis presented of key blocks formed by three and four discontinuity planes in underground excavations. The concept of non- pyramidal key blocks and their generation from a geometric operation called dislocation to determine the pentahedral key blocks that may be formed are described. The process was carried out using ASTUR (Analysis of the Support of Tunnels in Rock) software, which allows the analysis of both pyramidal and non-pyramidal tetrahedral and pentahedral blocks. The results can be used to investigate block stability as a function of the trend and plunge of a tunnel axis. Isoplethograms were used to illustrate how the block assembly might affect the design of an excavation. It is necessary to analyse the non-pyramidal key blocks with four discontinuity planes, since these may generate blocks with a large volume and a much lower safety factor than that obtained by blocks with three planes. The approach was applied to the design of an access tunnel in an underground room and pillar marble mine in Alicante, Spain., The key block method for analysing rock mass stability is reviewed and an analysis presented of key blocks formed by three and four discontinuity planes in underground excavations. The concept of non- pyramidal key blocks and their generation from a geometric operation called dislocation to determine the pentahedral key blocks that may be formed are described. The process was carried out using ASTUR (Analysis of the Support of Tunnels in Rock) software, which allows the analysis of both pyramidal and non-pyramidal tetrahedral and pentahedral blocks. The results can be used to investigate block stability as a function of the trend and plunge of a tunnel axis. Isoplethograms were used to illustrate how the block assembly might affect the design of an excavation. It is necessary to analyse the non-pyramidal key blocks with four discontinuity planes, since these may generate blocks with a large volume and a much lower safety factor than that obtained by blocks with three planes. The approach was applied to the design of an access tunnel in an underground room and pillar marble mine in Alicante, Spain.

A system is described for measuring tunnel convergence called CANG (Convergence by means of ANGular Sensors). The system is based on the measurement of an open polygon defined by a flexible steel wire attached to the perimeter of the tunnel at five points, P1, P2, P3, P4 and P5. Data capture modules are located at each point to guide the positioning of the wire by means of pulleys. The wire is fixed to the tunnel at point P1 by a pulley which acts as a ball-socket joint, while at the other points the wire rests on pulleys the axes of which are fixed to the tunnel. At the end of the wire at point P5 a 4-kg weight is used to keep the wire in tension through the force of gravity and to stop it from exiting the pulley guides. Additional data capture modules can be included depending on the cross-section of the tunnel. Each data capture module is autonomous and includes sensors for measuring the rotation of the wire, sensors for measuring the displacement of the wire, an electronic circuit for monitoring the signal, including a PIC micro-controller, and mechanical elements which guide the wire and transmit the rotations and displacements of the wire to the encoders. The measurements are used to calculate the shape of the polygon, determining at each instant the relative displacements and convergence. There is no need to remove the system to allow the movement of personnel or material, as the wire is always kept close to the perimeter of the tunnel, freeing up most of its useable cross-section. It may be left installed over long periods of time, providing a continuous record of convergence, and alarm signals can be introduced if high displacements are detected. Pilot implementation of the system in the Rellon road tunnel in Asturias, Spain, is described., A system is described for measuring tunnel convergence called CANG (Convergence by means of ANGular Sensors). The system is based on the measurement of an open polygon defined by a flexible steel wire attached to the perimeter of the tunnel at five points, P1, P2, P3, P4 and P5. Data capture modules are located at each point to guide the positioning of the wire by means of pulleys. The wire is fixed to the tunnel at point P1 by a pulley which acts as a ball-socket joint, while at the other points the wire rests on pulleys the axes of which are fixed to the tunnel. At the end of the wire at point P5 a 4-kg weight is used to keep the wire in tension through the force of gravity and to stop it from exiting the pulley guides. Additional data capture modules can be included depending on the cross-section of the tunnel. Each data capture module is autonomous and includes sensors for measuring the rotation of the wire, sensors for measuring the displacement of the wire, an electronic circuit for monitoring the signal, including a PIC micro-controller, and mechanical elements which guide the wire and transmit the rotations and displacements of the wire to the encoders. The measurements are used to calculate the shape of the polygon, determining at each instant the relative displacements and convergence. There is no need to remove the system to allow the movement of personnel or material, as the wire is always kept close to the perimeter of the tunnel, freeing up most of its useable cross-section. It may be left installed over long periods of time, providing a continuous record of convergence, and alarm signals can be introduced if high displacements are detected. Pilot implementation of the system in the Rellon road tunnel in Asturias, Spain, is described.