465 research outputs found

    Conhecimento e significado cultural da menopausa para um grupo de mulheres

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    Este estudio etnográfico, realizado con un grupo de mujeres, tuvo como objetivo verificar el nivel de conocimiento sobre la menopausia y comprender cómo ocurre la vivencia de este período biológico propio del sexo femenino. Para la recolección de los datos, se usó la observación participante, la entrevista, mediante el uso de una grabadora, además de dibujos previamente reproducidos. El análisis se llevó a cabo con base en las premisas teóricas, del método etnográfico y de algunos del interpretativismo biográfico. De las narrativas recolectadas, se extrajeron las categorías y los temas culturales. De este modo, fue posible verificar que el proceso de la menopausia era entendido como resultado de una construcción singular, estando integrado a una red de significados, instituidos por el grupo, los cuales condicionan el conocimiento y la vivencia dentro de determinados patrones culturales, entre ellos, el hecho de que la menopausia significa dejar de ser mujer.Este estudo etnográfico, realizado junto a um grupo de mulheres, teve como objetivo verificar o nível de conhecimento sobre a menopausa e compreender como ocorre a vivência deste estágio biológico próprio do sexo feminino. Para a coleta dos dados, usou-se a observação participante, a entrevista, mediante uso de gravador, além de desenhos previamente reproduzidos. A análise foi efetuada com base nos pressupostos teóricos, de método etnográfico e de alguns pressupostos do interpretativismo biográfico. Das narrativas coletadas, extraíram-se as categorias e os temas culturais. Assim, foi possível verificar que o processo da menopausa era entendido como resultante de uma construção singular, estando integrado a uma rede de significados, instituídos pelo grupo, os quais condicionam o conhecimento e a vivência dentro de determinados padrões culturais, entre eles, o fato de que a menopausa significa deixar de ser mulher.This ethnographic study is aimed at understanding a group of women's knowledge about menopause and how they experience it. The methods used for data collection were participant observation, recorded interviews and previously produced drawings. Data were analyzed based on a theoretical framework using both the ethnographic method and biographic interpretativism. From the narratives the authors obtained the cultural categories and themes. Thus it was possible to conclude that menopause is understood as a result of a unique construction integrated to a network of meanings built by the group that condition knowledge and experience within certain cultural patterns, among them the fact that menopause means leaving womanhood behind

    Extraction, Storage and Eruption of Multiple Isolated Magma Batches in the Paired Mamaku and Ohakuri Eruption, Taupo Volcanic Zone, New Zealand

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    The Taupo Volcanic Zone (TVZ) is well known for its extraordinary rate of rhyolitic magma generation and caldera-forming eruptions. Less is known about how large volumes of rhyolitic magma are extracted and stored prior to eruption, and the role tectonics might play in the process of melt extraction and control of caldera eruption(s). Here we present a new model for the extraction, storage and simultaneous eruption of the >245 km3 paired Mamaku and Ohakuri magmas sourced from calderas centred ∼30 km apart (the Rotorua and Ohakuri calderas, respectively) in the central TVZ. The Mamaku and Ohakuri ignimbrites share a similar bulk pumice composition and the same phenocryst assemblage; however, bulk-rock compositions suggest several poorly mixed magma types in each erupted volume, which are randomly distributed throughout the eruptive deposits. To refine models of the pre-eruptive geometry of the magmatic system and discuss a possible origin for triggering of each eruption, we present an expanded database of matrix glass and quartz-hosted melt inclusion compositions along with the existing bulk-rock and mineral compositions. Major and trace element compositions show that the region produced five different magma batches, extracted from the same source region, and a continuous intermediate mush zone beneath the Mamaku-Ohakuri region is suggested here. These magma batches were most probably juxtaposed but isolated from each other in the upper crust, and evolved separately until eruption. The observed geochemical differences between the batches are likely to be generated by different extraction conditions of the rhyolitic melt from a slightly heterogeneous mush. The lack of evidence for more mafic recharge prior to eruption (for example, there are no bright cathodoluminescence rims on quartz crystals) suggests that a magmatic input is unlikely to be an eruption trigger. However, tectonic activity could be an efficient way to trigger the eruption of isolated magma batches, with the evacuation of one magma batch causing a disturbance to the local stress field and activating regionally linked faults, which then lead to the eruption of additional magma batches and associated caldera subsidence. In addition, the extensional tectonic regime coupled with a high heat flux could be the controlling factor in the emplacement of some of the shallowest and most SiO2-rich magmas on Eart

    Timescales of Quartz Crystallization and the Longevity of the Bishop Giant Magma Body

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    Supereruptions violently transfer huge amounts (100 s–1000 s km3) of magma to the surface in a matter of days and testify to the existence of giant pools of magma at depth. The longevity of these giant magma bodies is of significant scientific and societal interest. Radiometric data on whole rocks, glasses, feldspar and zircon crystals have been used to suggest that the Bishop Tuff giant magma body, which erupted ∼760,000 years ago and created the Long Valley caldera (California), was long-lived (>100,000 years) and evolved rather slowly. In this work, we present four lines of evidence to constrain the timescales of crystallization of the Bishop magma body: (1) quartz residence times based on diffusional relaxation of Ti profiles, (2) quartz residence times based on the kinetics of faceting of melt inclusions, (3) quartz and feldspar crystallization times derived using quartz+feldspar crystal size distributions, and (4) timescales of cooling and crystallization based on thermodynamic and heat flow modeling. All of our estimates suggest quartz crystallization on timescales of <10,000 years, more typically within 500–3,000 years before eruption. We conclude that large-volume, crystal-poor magma bodies are ephemeral features that, once established, evolve on millennial timescales. We also suggest that zircon crystals, rather than recording the timescales of crystallization of a large pool of crystal-poor magma, record the extended periods of time necessary for maturation of the crust and establishment of these giant magma bodies

    Climbing the crustal ladder: Magma storage-depth evolution during a volcanic flare-up

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    © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Science Advances 4 (2018): eaap7567, doi:10.1126/sciadv.aap7567.Very large eruptions (>50 km3) and supereruptions (>450 km3) reveal Earth’s capacity to produce and store enormous quantities (>1000 km3) of crystal-poor, eruptible magma in the shallow crust. We explore the interplay between crustal evolution and volcanism during a volcanic flare-up in the Taupo Volcanic Zone (TVZ, New Zealand) using a combination of quartz-feldspar-melt equilibration pressures and time scales of quartz crystallization. Over the course of the flare-up, crystallization depths became progressively shallower, showing the gradual conditioning of the crust. Yet, quartz crystallization times were invariably very short (<100 years), demonstrating that very large reservoirs of eruptible magma were transient crustal features. We conclude that the dynamic nature of the TVZ crust favored magma eruption over storage. Episodic tapping of eruptible magmas likely prevented a supereruption. Instead, multiple very large bodies of eruptible magma were assembled and erupted in decadal time scales.This work was supported by the NSF (EAR-1151337) and by two Vanderbilt University Discovery Grants

    Clearance of senescent macrophages ameliorates tumorigenesis in KRAS-driven lung cancer

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    The accumulation of senescent cells in the tumor microenvironment can drive tumorigenesis in a paracrine manner through the senescence-associated secretory phenotype (SASP). Using a new p16-FDR mouse line, we show that macrophages and endothelial cells are the predominant senescent cell types in murine KRAS-driven lung tumors. Through single cell transcriptomics, we identify a population of tumor-associated macrophages that express a unique array of pro-tumorigenic SASP factors and surface proteins and are also present in normal aged lungs. Genetic or senolytic ablation of senescent cells, or macrophage depletion, result in a significant decrease in tumor burden and increased survival in KRAS-driven lung cancer models. Moreover, we reveal the presence of macrophages with senescent features in human lung pre-malignant lesions, but not in adenocarcinomas. Taken together, our results have uncovered the important role of senescent macrophages in the initiation and progression of lung cancer, highlighting potential therapeutic avenues and cancer preventative strategies

    Sexuality in the puerperium: the experience of a group of women

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    Puerperium is a period of great changes in women's lives, in physiological, psychological and socio-cultural terms. Female sexuality is a broad topic that should be explored vis-à-vis the singularity of woman's experiences which themselves vary at different moments in time. This article is part of the project: Sexuality in the Puerperium, the objective of which was to understand what women's experience of their sexuality is in the postpartum period. Observation and semi-structured interview were used. The research approach was qualitative and narrative was used as the conceptual and methodological method. Six primiparas who gave birth in a public hospital in São Paulo took part in the study. Observation took place in the in-patients unit in the immediate post-partum period. The interviews were conducted in the women´s homes. The results of the study have enabled an understanding to be formed of the meanings and changes in sexuality during the postpartum period as well as of the experiences every woman faces in her new roles, relationships and difficulties.El puerperio es un período de grandes transformaciones en los ámbitos fisiológico, psicológico y sociocultural de la vida de la mujer. La sexualidad femenina es un tema amplio que debe ser explorado tomando en cuenta la singularidad de sus experiencias en los diversos momentos. Este artículo es parte del proyecto: Sexualidad en el Puerperio, que tuvo como objetivo comprender el modo en que las mujeres experimentan la sexualidad en el puerperio. El abordaje de la investigación fue cualitativo, y la narrativa se constituyó en el elemento conceptual y metodológico, habiéndose utilizado la observación y entrevistas semiestructuradas. Participaron del estudio seis primerizas que tuvieron sus partos en un hospital público de São Paulo, Brasil. La observación tuvo lugar en la unidad de internación en el postparto inmediato. Las entrevistas se realizaron en domicilio. Los resultados permitirán comprender los significados y cambios en la sexualidad durante el período, así como las experiencias de cada mujer frente a los nuevos roles, relaciones y dificultades.O puerpério é um período de grandes transformações no âmbito fisiológico, psicológico e sócio-cultural na vida da mulher. A sexualidade feminina é tema amplo, que deve ser explorado frente à singularidade de suas vivências, em diversos momentos. Este artigo é parte do projeto Sexualidade no Puerpério, que teve como objetivo compreender como as mulheres vivenciam a sexualidade nesse período. A abordagem da pesquisa foi qualitativa e a narrativa foi o elemento conceitual e metodológico, com a utilização de observação e entrevista semi-estruturada. Participaram do estudo seis prímiparas que tiveram seus partos em um hospital público de São Paulo. A observação ocorreu na unidade de internação no pós-parto imediato. As entrevistas foram realizadas nos seus domicílios. Os resultados permitiram compreender os significados e as mudanças na sexualidade durante o período, bem como as vivências de cada mulher frente aos novos papéis, aos relacionamentos e às dificuldades

    Pre-eruptive magmatic processes re-timed using a non-isothermal approach to magma chamber dynamics

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    Open Source PaperThis work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. The attached file is the published version of the article

    Recent advances in organic synthesis using light-mediated n-heterocyclic carbene catalysis

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    The combination of photocatalysis with other ground state catalytic systems have attracted much attention recently due to the enormous synthetic potential offered by a dual activation mode. The use of N-heterocyclic carbene (NHC) as organocatalysts emerged as an important synthetic tool. Its ability to harness umpolung reactivity by the formation of the Breslow intermediate has been employed in the synthesis of thousands of biologically important compounds. However, the available coupling partners are relatively restricted, and its combination with other catalytic systems might improve its synthetic versatility. Thus, merging photoredox and N-heterocyclic carbene (NHC) catalysis has emerged recently as a powerful strategy to develop new transformations and give access to a whole new branch of synthetic possibilities. This review compiles the NHC catalyzed methods mediated by light, either in the presence or absence of an external photocatalyst, that have been described so far, and aims to give an accurate overview of the potential of this activation modeL.M. acknowledges the Autonomous Community of Madrid (CAM) for the financial support (PEJD-2019-PRE/AMB-16640 and SI1/PJI/ 2019-00237) and for an “Atracción de Talento Investigador” contract (2017-T2/AMB-5037

    Variability of indication criteria in knee and hip replacement: an observational study

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    <p>Abstract</p> <p>Background</p> <p>Total knee (TKR) and hip (THR) replacement (arthroplasty) are effective surgical procedures that relieve pain, improve patients' quality of life and increase functional capacity. Studies on variations in medical practice usually place the indications for performing these procedures to be highly variable, because surgeons appear to follow different criteria when recommending surgery in patients with different severity levels. We therefore proposed a study to evaluate inter-hospital variability in arthroplasty indication.</p> <p>Methods</p> <p>The pre-surgical condition of 1603 patients included was compared by their personal characteristics, clinical situation and self-perceived health status. Patients were asked to complete two health-related quality of life questionnaires: the generic SF-12 (Short Form) and the specific WOMAC (Western Ontario and Mcmaster Universities) scale. The type of patient undergoing primary arthroplasty was similar in the 15 different hospitals evaluated.</p> <p>The variability in baseline WOMAC score between hospitals in THR and TKR indication was described by range, mean and standard deviation (SD), mean and standard deviation weighted by the number of procedures at each hospital, high/low ratio or extremal quotient (EQ<sub>5-95</sub>), variation coefficient (CV<sub>5-95</sub>) and weighted variation coefficient (WCV<sub>5-95</sub>) for 5-95 percentile range. The variability in subjective and objective signs was evaluated using median, range and WCV<sub>5-95</sub>. The appropriateness of the procedures performed was calculated using a specific threshold proposed by Quintana et al for assessing pain and functional capacity.</p> <p>Results</p> <p>The variability expressed as WCV<sub>5-95 </sub>was very low, between 0.05 and 0.11 for all three dimensions on WOMAC scale for both types of procedure in all participating hospitals. The variability in the physical and mental SF-12 components was very low for both types of procedure (0.08 and 0.07 for hip and 0.03 and 0.07 for knee surgery patients). However, a moderate-high variability was detected in subjective-objective signs. Among all the surgeries performed, approximately a quarter of them could be considered to be inappropriate.</p> <p>Conclusions</p> <p>A greater inter-hospital variability was observed for objective than for subjective signs for both procedures, suggesting that the differences in clinical criteria followed by surgeons when indicating arthroplasty are the main responsible factors for the variation in surgery rates.</p
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