1,003 research outputs found
The property on Taquile Island, Titicaca lake
Un ensayo etnológico y etnohistórico que describe la lucha por la propiedad de las tierras de cultivo de una comunidad indígena de habla quechua ubicada en una isla del Lago Titicaca. En la segunda mitad del siglo XVI fue adjudicada en remate a un español y desde entonces en sucesivos remates a otros hasta el siglo XVIII en que propietarios puneños la explotaron como su hacienda considerando colonos a sus habitantes.En 1942 los indígenas lograron iniciar la compra de sus tierras con título de propiedad, una singular reforma agraria que los hizo dueños respaldados por documentos públicos. Estudio apasionante de las vicisitudes y luchas por lograrlo y de la situación de la isla Taquile en la década 1950.ownership of farmland in a Quechua speaking native community located in an island on Lake Titicaca. Taquile was sold at auction to a Spaniard during the second half of the XVI century and then successively to others at several auctions until the XVIII century, when owners from Puno developed it as their own estate, referring to its inhabitants as settlers. A remarkable agrarian reform began in 1942, when the natives started buying their land and obtaining official title deeds to their property. A passionate study about their struggle to achieve this and the state of affairs in Taquile island during the fifties
Spatio-temporal tumor heterogeneity in metastatic CRC tumors: a mutational-based approach
[EN] It is well known that activating mutations in the KRAS and NRAS genes are associated with poor response to anti-EGFR therapies in patients with metastatic colorectal cancer (mCRC). Approximately half of the patients with wild-type (WT) KRAS colorectal carcinoma do not respond to these therapies. This could be because the treatment decision is determined by the mutational profile of the primary tumor, regardless of the presence of small tumor subclones harboring RAS mutations in lymph nodes or liver metastases. We analyzed the mutational profile of the KRAS, NRAS, BRAF and PI3KCA genes using low-density microarray technology in samples of 26 paired primary tumors, 16 lymph nodes and 34 liver metastases from 26 untreated mCRC patients (n=76 samples). The most frequent mutations found in primary tumors were KRAS (15%) and PI3KCA (15%), followed by NRAS (8%) and BRAF (4%). The distribution of the mutations in the 16 lymph node metastases analyzed was as follows: 4 (25%) in KRAS gene, 3 (19%) in NRAS gene and 1 mutation each in PI3KCA and BRAF genes (6%). As expected, the most prevalent mutation in liver metastasis was in the KRAS gene (35%), followed by PI3KCA (9%) and BRAF (6%). Of the 26 cases studied, 15 (58%) displayed an overall concordance in the mutation status detected in the lymph node metastases and liver metastases compared with primary tumor, suggesting no clonal evolution. In contrast, the mutation profiles differed in the primary tumor and lymph node/metastases samples of the remaining 11 patients (48%), suggesting a spatial and temporal clonal evolution. We confirm the presence of different mutational profiles among primary tumors, lymph node metastases and liver metastases. Our results suggest the need to perform mutational analysis in all available tumor samples of patients before deciding to commence anti-EGFR treatment
Does the mass of the Earth vary? Modeling through thought experiment
El artículo analiza el efecto de la resolución de problemas cualitativos mediante experimentos
mentales, en el uso de la idea de conservación de la masa. Se trata de identificar los modelos
expresados por los estudiantes y cómo estos se ajustan y autorregulan a partir del trabajo en el aula.
Para ello se realiza un estudio de casos múltiples con estudiantes de secundaria obligatoria, empleando
métodos cualitativos de análisis de datos. A lo largo del experimento mental, los estudiantes empezaron
movilizando modelos ingenuos y simples, basados en la no conservación de la materia, y más de
la mitad terminó formulando otros que integraban el principio de conservación de la masa y la idea
de Tierra como sistema abierto. Ello sugiere el papel de los experimentos mentales como escenarios
propicios para favorecer procesos de modelización en ciencias.This paper analyzes the effect of the resolution of qualitative problems through mental
experiments, in the use of the idea of conservation of mass. Its purpose is to identify the models expressed
by the students, and how they adjust and self-regulate as a result of the work in the classroom.
For this, a multiple case study is carried out with secondary school students, using qualitative methods
of data analysis. Throughout the mental experiment, students began mobilizing simple and naive
models, based on a non-conservation of matter, while more than half ended up formulating others that
spontaneously integrated the principle of conservation of mass and the idea of Earth as an open system.
These results show the role of mental experiments as favorable scenarios for modeling in science
A Guide to Carrying Out a Phylogenomic Target Sequence Capture Project
High-throughput DNA sequencing techniques enable time- and cost-effective sequencing of large portions of the genome. Instead of sequencing and annotating whole genomes, many phylogenetic studies focus sequencing effort on large sets of pre-selected loci, which further reduces costs and bioinformatic challenges while increasing coverage. One common approach that enriches loci before sequencing is often referred to as target sequence capture. This technique has been shown to be applicable to phylogenetic studies of greatly varying evolutionary depth. Moreover, it has proven to produce powerful, large multi-locus DNA sequence datasets suitable for phylogenetic analyses. However, target capture requires careful considerations, which may greatly affect the success of experiments. Here we provide a simple flowchart for designing phylogenomic target capture experiments. We discuss necessary decisions from the identification of target loci to the final bioinformatic processing of sequence data. We outline challenges and solutions related to the taxonomic scope, sample quality, and available genomic resources of target capture projects. We hope this review will serve as a useful roadmap for designing and carrying out successful phylogenetic target capture studies. © Copyright © 2020 Andermann, Torres Jiménez, Matos-Maraví, Batista, Blanco-Pastor, Gustafsson, Kistler, Liberal, Oxelman, Bacon and Antonelli
A Guide to Carrying Out a Phylogenomic Target Sequence Capture Project
High-throughput DNA sequencing techniques enable time- and cost-effective sequencing of large portions of the genome. Instead of sequencing and annotating whole genomes, many phylogenetic studies focus sequencing effort on large sets of pre-selected loci, which further reduces costs and bioinformatic challenges while increasing coverage. One common approach that enriches loci before sequencing is often referred to as target sequence capture. This technique has been shown to be applicable to phylogenetic studies of greatly varying evolutionary depth. Moreover, it has proven to produce powerful, large multi-locus DNA sequence datasets suitable for phylogenetic analyses. However, target capture requires careful considerations, which may greatly affect the success of experiments. Here we provide a simple flowchart for designing phylogenomic target capture experiments. We discuss necessary decisions from the identification of target loci to the final bioinformatic processing of sequence data. We outline challenges and solutions related to the taxonomic scope, sample quality, and available genomic resources of target capture projects. We hope this review will serve as a useful roadmap for designing and carrying out successful phylogenetic target capture studies. © Copyright © 2020 Andermann, Torres Jiménez, Matos-Maraví, Batista, Blanco-Pastor, Gustafsson, Kistler, Liberal, Oxelman, Bacon and Antonelli
A Guide to Carrying Out a Phylogenomic Target Sequence Capture Project
High-throughput DNA sequencing techniques enable time- and cost-effective sequencing of large portions of the genome. Instead of sequencing and annotating whole genomes, many phylogenetic studies focus sequencing effort on large sets of pre-selected loci, which further reduces costs and bioinformatic challenges while increasing coverage. One common approach that enriches loci before sequencing is often referred to as target sequence capture. This technique has been shown to be applicable to phylogenetic studies of greatly varying evolutionary depth. Moreover, it has proven to produce powerful, large multi-locus DNA sequence datasets suitable for phylogenetic analyses. However, target capture requires careful considerations, which may greatly affect the success of experiments. Here we provide a simple flowchart for designing phylogenomic target capture experiments. We discuss necessary decisions from the identification of target loci to the final bioinformatic processing of sequence data. We outline challenges and solutions related to the taxonomic scope, sample quality, and available genomic resources of target capture projects. We hope this review will serve as a useful roadmap for designing and carrying out successful phylogenetic target capture studies. © Copyright © 2020 Andermann, Torres Jiménez, Matos-Maraví, Batista, Blanco-Pastor, Gustafsson, Kistler, Liberal, Oxelman, Bacon and Antonelli
Entre realismo y ciencia-ficción
This paper aims to analyse the novel Mañana, las ratas by German-Peruvian writer José Bernardo Adolph. Written in 1977 and published in 1984 the text is a dystopian novel set in a distant future, that nevertheless is a vivid representation of the dynamics and the conflicts of the Peruvian society of the 70s and 80s. This study intends to investigate the structure of the novel in order to point out how the author succeeds in blending together two different literary genres such as dystopian fiction and realism, creating a new version of the classic paradigm of dystopic narrative. To do so, the research will concentrate on the study of some significant example of the Adolph's previous books, and on the intertextual connections of Mañana, las ratas with both classic dystopian novels such as 1984, We or Brand New World and writers such as José Diez-Canseco, Sebastián Salazar Bondy, Julio Ramón Ribeyro, Alfredo Bryce Echenique y Mario Vargas Llosa, whose texts explore through different mode of realism social and political issues of their time
Role of age and comorbidities in mortality of patients with infective endocarditis
[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality.
[Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk.
[Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality.
[Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group
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