Domain Wall Engineering of Nanoscale Ferromagnetic Elements and its Application for Memory Devices

This thesis concerns the interaction of spin polarized electrons with the local magnetic moments in nanopatterned metallic systems. We study novel magnetic phenomena appearing in patterned thin film magnetic wires with length scales in the nanometer regime and in magnetic multilayers. The work has three mayor foci. The first is the interaction between magnetic domain walls and conduction electrons in single layer nanowires. We demonstrate the effect of using small constrictions as artificial traps for domain walls and use these structures to measure the contribution of a domain wall to the electrical resistivity. These measurements are correlated with the specific micromagnetic distribution induced by the constriction geometry. Similarly, we demonstrate and characterize the effect of spin current induced magnetization reversal in nanowires. This includes a measurement of the critical current/field phase space boundary between static and moving walls and an estimation of the intrinsic wall mobility. The second is focused on understanding the effects of spin currents on magnetoresistance and domain wall motion, in a multilayer nanostructure device exhibiting giant magnetoresistance (GMR). To demonstrate a potential application, we incorporate the effects of domain wall trapping and spin current induced domain wall motion into a nanometer scale spin-valve device. The device can be fully controlled through current and exhibits significant GMR response. This approach may be useful as a memory element in magnetoresistive random access memory (MRAM) technology, and the device serves as a proof of concept. The third focus is the understanding of the effect strain on the resistance of antiferromagnetically (AF) coupled giant magnetoresistive (GMR) multilayers containing highly magnetostrictive materials. Our measurements reveal that inverse magnetostriction effects lead to enhanced strain sensitivity in comparison to films made of the materials that compose the multilayer. A simple phenomenological model describing the measured field dependence of these effects is used to identify field-biasing values that optimize amplitude, linearity and reversibility of the effect

CONTRATACIÓN LABORAL DEL SECTOR INDUSTRIAL, UNA MEJORA PARA EL BIENESTAR SOCIAL

A nivel mundial, las últimas tres décadas han sido caracterizadas por dos grandes tendencias: el tránsito hacia economías abiertas y globalizadas y el cambio en el papel económico del Estado, generando impacto sobre el mercado de trabajo como: el ajuste de la economía en el corto plazo y las políticas laborales, fortaleciendo la relación entre mano de obra y competitividad organizacional. Este artículo se basa en la investigación donde se identificaron los tipos de contratación vigentes en el sector industrial de Pereira y Dosquebradas que permitieron visualizar las ventajas y desventajas para el empleador y el trabajador

CONTRATACIÓN LABORAL DEL SECTOR INDUSTRIAL, UNA MEJORA PARA EL BIENESTAR SOCIAL

A nivel mundial, las últimas tres décadas han sido caracterizadas por dos grandes tendencias: el tránsito hacia economías abiertas y globalizadas y el cambio en el papel económico del Estado, generando impacto sobre el mercado de trabajo como: el ajuste de la economía en el corto plazo y las políticas laborales, fortaleciendo la relación entre mano de obra y competitividad organizacional. Este artículo se basa en la investigación donde se identificaron los tipos de contratación vigentes en el sector industrial de Pereira y Dosquebradas que permitieron visualizar las ventajas y desventajas para el empleador y el trabajador

Untangling the transmission dynamics of primary and secondary vectors of Trypanosoma cruzi in Colombia : Parasite infection, feeding sources and discrete typing units

Background: Trypanosoma cruzi is the causative agent of Chagas disease. Due to its genetic diversity has been classified into six Discrete Typing Units (DTUs) in association with transmission cycles. In Colombia, natural T. cruzi infection has been detected in 15 triatomine species. There is scarce information regarding the infection rates, DTUs and feeding preferences of secondary vectors. Therefore, the aim of this study was to determine T. cruzi infection rates, parasite DTU, ecotopes, insect stages, geographical location and bug feeding preferences across six different triatomine species. Methods: A total of 245 insects were collected in seven departments of Colombia. We conducted molecular detection and genotyping of T. cruzi with subsequent identification of food sources. The frequency of infection, DTUs, TcI genotypes and feeding sources were plotted across the six species studied. A logistic regression model risk was estimated with insects positive for T. cruzi according to demographic and eco-epidemiological characteristics. Results: We collected 85 specimens of Panstrongylus geniculatus, 77 Rhodnius prolixus, 37 R. pallescens, 34 Triatoma maculata, 8 R. pictipes and 4 T. dimidiata. The overall T. cruzi infection rate was 61.2% and presented statistical associations with the departments Meta (OR: 2.65; 95% CI: 1.69-4.17) and Guajira (OR: 2.13; 95% CI: 1.16-3.94); peridomestic ecotope (OR: 2.52: 95% CI: 1.62-3.93); the vector species P. geniculatus (OR: 2.40; 95% CI: 1.51-3.82) and T. maculata (OR: 2.09; 95% CI: 1.02-4.29); females (OR: 2.05; 95% CI: 1.39-3.04) and feeding on opossum (OR: 3.15; 95% CI: 1.85-11.69) and human blood (OR: 1.55; 95% CI: 1.07-2.24). Regarding the DTUs, we observed TcI (67.3%), TcII (6.7%), TcIII (8.7%), TcIV (4.0%) and TcV (6.0%). Across the samples typed as TcI, we detected TcIDom (19%) and sylvatic TcI (75%). The frequencies of feeding sources were 59.4% (human blood); 11.2% (hen); 9.6% (bat); 5.6% (opossum); 5.1% (mouse); 4.1% (dog); 3.0% (rodent); 1.0% (armadillo); and 1.0% (cow). Conclusions: New scenarios of T. cruzi transmission caused by secondary and sylvatic vectors are considered. The findings of sylvatic DTUs from bugs collected in domestic and peridomestic ecotopes confirms the emerging transmission scenarios in Colombia. © 2016 The Author(s)

La imagen y la narrativa como herramientas para el abordaje psicosocial en escenarios de violencia. Departamentos de la Guajira, Cesar, Santander y Magdalena.

La imagen y la narrativa como herramientas para el abordaje psicosocial en escenarios de violencia. Departamentos de la Guajira, Cesar, Santander y Magdalena.El enfoque narrativo en la psicología contemporánea ha logrado un camino reflexivo significativo en los abordajes terapéuticos y psicosociales de violencias sistemáticas. En el caso colombiano es importante reconocer sus aportes desde los marcos diversos y contextuales de nuestra realidad socio-política. De aquí que para tener un acercamiento a estos desarrollos conceptuales el grupo colaborativo realizará una tarea haciendo un análisis de diferentes relatos de violencia socio-política en Colombia, donde abordaremos y nos acercaremos a las subjetividades inmersas en estos contextos. La narrativa busca un acercamiento respetuoso, de la intervención y el trabajo comunitario centrando a la persona como expertos en su vida. Viendo el problema separado de las personas y asume que las personas tienen muchas habilidades, competencias, convicciones, valores, compromisos y capacidades que los asistirá a reducir la influencia del problema en sus vidas. Las historias o narrativas son importantes y para la terapia narrativa, la palabra historia o narrativa significa: eventos, ligados en una secuencia, a través del tiempo y de acuerdo con un tema. En el siguiente informe, se dará a conocer la percepción del grupo colaborativo sobre los relatos de violencia y esperanza en Colombia desde la perspectiva narrativa, del mismo modo se realizarán preguntas encaminadas aplicadas a cada relato en sus diferentes etapas, por último, se realizarán reflexiones sobre su abordaje y propondrá tres estrategias de acompañamiento psicosocial para el caso de Pandurí.The narrative approach in contemporary psychology has achieved a significant reflective path in the therapeutic and psychosocial approaches of systematic violence. In the Colombian case it is important to recognize their contributions from the diverse and contextual frameworks of our socio-political reality. Hence, to have an approach to these conceptual developments, the collaborative group will carry out a task by analyzing different accounts of socio-political violence in Colombia, where we will approach and approach the subjectivities immersed in these contexts. The narrative seeks a respectful approach, intervention and community work focusing the person as experts in their lives. Seeing the problem separate from people and assumes that people have many skills, competencies, convictions, values, commitments and capabilities that will help them reduce the influence of the problem in their lives. Stories or narratives are important and for narrative therapy, the word history or narrative means: events, linked in a sequence, through time and according to a theme. In the following report, the perception of the collaborative group about the narratives of violence and hope in Colombia will be made known from the narrative perspective. In the same way, guided questions will be made applied to each story in its different stages. Finally, reflections will be made on its approach and propose three strategies of psychosocial accompaniment for the case of Pandurí

Vertebral fracture risk in glucocorticoid-induced osteoporosis: the role of hypogonadism and corticosteroid boluses

Objective: The aim of this study was to identify the risk factors associated with fragility fracture (FF) development in glucocorticoid (GC)-treated patients. Methods: 127 patients (aged 62±18 years, 63% women) on GC-treatment (mean dose 14.5±14.1 mg/day and duration 47.7±69 months) were included. The clinical data collected included bone metabolism study (including gonadal axis), GC-treatment, disease activity, dual-energy X-ray absorptiometry analysis (evaluating densitometric osteoporosis (OP) and trabecular bone score (TBS) degraded microarchitecture values (DMA)), X-ray (assessing vertebral fractures (VF)), FRAX risk (GC-adjusted) and previous FF. Results: 17% of the patients had VF, 28% FF (VF and/or non-VF), 29% OP and 52% DMA. Patients with VF received more GC boluses (57.1% vs 29.5%, p=0.03), were older (68±13 vs 60±19 years, p=0.02), postmenopausal (100% vs 67%, p=0.02), had low testosterone levels (57% vs 11%, p=0.02), lower TBS values (1.119±0.03 vs 1.237±0.013, p100, p=0.01) and having received GC boluses (OR 3.45; 95% CI 1.04 to 12.15, p=0.01) were the main factors related to VF. Hypogonadism (OR 7.03; 95% CI 1.47 to 38.37, p=0.01) and FRAX >20 (OR 7.08; 95% CI 1.28 to 53.71, p=0.02) were factors related to FF. Conclusion: Hypogonadism is the principal risk factor for developing fractures in GC-treated men and women, whereas receiving GC boluses is a major factor for VF. These results indicate the importance of evaluating the gonadal axis in these patients

Bogotá paint-industry workers' exposure to organic solvents and genotoxic effects

Objetivo Investigar la exposición a solventes orgánicos y los efectos genotóxicos mediante monitoreo citogenético determinando la frecuencia de micronúcleos en linfocitos y el daño del ADN por el ensayo del cometa, en trabajadores de fábricas de pinturas en Bogotá. Metodología Como biomarcadores de exposición a benceno, tolueno y xileno, la excreción de fenol, ácido hipúrico y ácido metilhipúrico fue investigada en muestras de orina provenientes de trabajadores en dos fábricas de pinturas en Bogotá y de un grupo control. También se realizó monitoreo de la concentración de benceno, tolueno y xileno en el ambiente de trabajo. Como biomarcadores de efectos genéticos tempranos, la frecuencia de micronúcleos y rompimiento de cadenas simples de ADN fueron evaluadas en células mononucleares a partir de muestras de sangre periférica. Resultados Las concentraciones de ácido hipúrico en orina post-exposición se encontraron dentro de los rangos normales, mientras que para fenol el 3,3 % y para ácido metilhipúrico el 50,8 % de las muestras presentaron niveles por encima de los valores de referencia. En una de las fábricas la concentración de benceno en aire estaba por encima de los valores límites permisibles. No hubo diferencias estadísticas entre los trabajadores expuestos y los no expuestos con relación a los biomarcadores genéticos examinados. Conclusiones En este estudio los niveles de solventes orgánicos internamente efectivos parecen ser bajos lo cual se explica con la ausencia de efectos genotóxicos en las células examinadas. Este trabajo constituye un aporte para continuar investigando sobre el tema y a la vez hacer seguimiento por medio del programa de vigilancia epidemiológica.Objective Investigating the degree of exposure to organic solvents and related genotoxic consequences in paint-factory workers by using cytogenetic monitoring and determining micronuclei frequency in lymphocytes and DNA damage as assessed by comet assays. Methodology Excretion of phenol and hippuric and methylhippuric acids in urine was investigated as biomarkers for benzene, toluene and xylene exposure. Urine samples were taken in two paint-factories in Bogotá and in a non-exposed control group. Benzene, toluene and xylene concentrations in air were measured in the work setting. Micronuclei and simple DNA chain breakage frequency were evaluated in peripheral blood sample mononuclear cells to assess early genetic effects. Results Hippuric acid concentration was found to be within normal values; by contrast, phenol and methylhippuric acid sample concentrations were above normal values by 3,3 % and 50,8 %, respectively. Benzene concentration in air was above permissible limits in one of the factories. There were no statistical differences regarding genetic biomarkers between exposed and non-exposed workers. Conclusions Organic solvent levels in the samples were apparently low, which is consistent with the absence of genotoxicity in cells. This study represents a step forward in research in occupational health surveillance

The incidence of clinical fractures in adults aged 50 years and older in Spain

Objective. The aim of this study was to quantify the incidence of all clinical fractures, including traumatic and fragility fractures, in patients aged 50 years and older, and to describe their distribution by fracture location, sex and age. Methods. The incidence of clinical fractures at 10 hospitals in Catalonia, with a reference population of 3 155 000 inhabitants, was studied. For 1 week, from 30 May to 5 June 2016, we reviewed the discharge reports of the Traumatology section of the Emergency Department to identify all fractures diagnosed in patients ≥50 years of age. As a validation technique, data collection was carried out for 1 year at one of the centres, from 1 December 2015 to 30 November 2016. The fracture incidence, including the 95% CI, was estimated for the entire sample and grouped by fracture type, location, sex and age. Results. A total of 283 fractures were identified. Seventy per cent were in women, with a mean age of 72 years. The overall fracture incidence was 11.28 per 1000 person-years (95% CI: 11.10, 11.46), with an incidence of traumatic and fragility fractures of 4.15 (95% CI: 4.04, 4.26) and 7.13 per 1000 person-years (95% CI: 6.99, 7.28), respectively. The incidence of fractures observed in the validation sample coincided with that estimated for the whole of Catalonia. The most common fragility fractures were of the hip, forearm, humerus and vertebrae. Conclusion. The results of this study are the first to estimate the incidence of clinical fragility fractures in Spain, grouped by location, age and sex

High incidence of clinical fragility fractures in postmenopausal women with rheumatoid arthritis. A case-control study.

Objectives: To estimate the incidence of clinical fragility fractures in postmenopausal women with rheumatoid arthritis (RA) and analyze risk factors for fracture. Methods: Incidence of clinical fragility fractures in 330 postmenopausal women with RA was compared to that of a control population of 660 age-matched postmenopausal Spanish women. Clinical fractures during the previous five years were recorded. We analyzed associations with risk factors for fracture in both populations and with disease-related variables in RA patients. Results: Median age of RA patients was 64 years; median RA duration was eight years. Sixty-nine percent were in remission or on low activity. Eighty-five percent had received glucocorticoids (GCs); 85 %, methotrexate; and 40 %, ≥1 biologic DMARD. Fifty-four patients and 47 controls had ≥1 major osteoporotic fracture (MOF). Incidence of MOFs was 3.55 per 100 patient-year in patients and 0.72 in controls (HR: 2.6). Risk factors for MOFs in RA patients were age, previous fracture, parental hip fracture, years since menopause, BMD, erosions, disease activity and disability, and cumulative dose of GCs. Previous fracture in RA patients was a strong risk for MOFs (HR: 10.37). Conclusion: Of every 100 postmenopausal Spanish women with RA, 3-4 have a MOF per year. This is more than double that of the general population. A previous fracture poses a high risk for a new fracture. Other classic risk factors for fracture, RA disease activity and disability, and the cumulative dose of GCs are associated with fracture development

Anatomical grouping and characterization of wood of native species of the Araucaria Forest

Artigo OriginalIn the Araucaria Forest in addition to floristic diversity, studies on the anatomical diversity of wood of native species are required. Therefore, this work aimed to characterize anatomically and evaluate the similarities and the main anatomical characteristics that vary between the wood of 14 native species of the Araucaria Forest. For the characterizations, the procedures determined by IAWA (1989) were followed. Fourteen anatomical variables were used to apply the Manhattan similarity and Principal Component Analysis (PCA). As result, it can be observed that the species present common characteristics, such as diffuse porosity and alternate intervessel pits. In addition, the presence of septate fibers and axial parenchyma scarce in 50% of the woods were remarkable characteristics for the species of the region. As for the similarity, was observed the division by the dimensions of the rays, vessels and pits. In PCA, the diameter of the vessel, width and height of the radius, the height of the radius in number of cells, the intervessel pits and the radius-vascular were emphasized. In conclusion, even with the great anatomical diversity, it is possible to differentiate the wood from the species of the Araucaria Forest, which occur naturally in the region of Planalto Catarinenseinfo:eu-repo/semantics/publishedVersio