Comparación técnica y económica entre edificaciones de adobe confinado y adobe reforzado con cañas

En el Perú, se registra un porcentaje considerable de viviendas que tienen como material predominante el adobe en sus paredes exteriores. Este material, específicamente en áreas rurales del país, constituye una alternativa económicamente viable para la construcción de viviendas. El adobe se caracteriza por ser un material práctico, manejable y sustentable. Sin embargo, una limitante de este material es que el proceso de fabricación se realiza de manera artesanal con múltiples factores que afectan sus características y propiedades. Esto debido a que los sistemas y técnicas de construcción son aplicados con conocimiento empírico sin criterios sismorresistentes. Actualmente, se han desarrollado técnicas constructivas con métodos de reforzamiento que aumenta la resistencia de las estructuras y reduce el riesgo ante eventos sísmicos. Sin embargo, algunos de estos métodos no son aceptados por la Norma E.080, como el adobe confinado con elementos del concreto armado. Como respuesta a dicho contexto, la presente tesis tiene como objetivo realizar la comparación técnica y económica entre edificaciones diseñadas con adobe reforzado con cañas aceptado por la norma E.080 y el adobe confinado con elementos de concreto. Para ello, las edificaciones de estudio se ubican en los distritos de Orcopampa y Pampacolca del departamento de Arequipa. Para realizar el análisis, se diseña ambas edificaciones con ambos métodos de reforzamiento y se elabora el presupuesto estimado en su construcción. La comparación técnica abarca la sobreresistencia que tiene cada edificación, mientras que la comparación económica es influenciada por el análisis de precios unitarios. Los resultados revelan que las estructuras de adobe confinado presentan mayor sobreresistencia. Asimismo, la evaluación de costos evidencia que la propuesta más económica es la edificación diseñada con adobe reforzada con cañas alrededor del 20% aproximadamente del costo directo. Sin embargo, tratándose de edificaciones esenciales e importantes las analizadas en la presente tesis, se concluye que la propuesta de construcción más adecuada es la del adobe confinado con elementos de concreto armado debido a que se debe privilegiar la resistencia

Organic–inorganic interfaces and spiral growth in nacre

Nacre, the crown jewel of natural materials, has been extensively studied owing to its remarkable physical properties for over 160 years. Yet, the precise structural features governing its extraordinary strength and its growth mechanism remain elusive. In this paper, we present a series of observations pertaining to the red abalone (Haliotis rufescens) shell's organic–inorganic interface, organic interlayer morphology and properties, large-area crystal domain orientations and nacre growth. In particular, we describe unique lateral nano-growths and paired screw dislocations in the aragonite layers, and demonstrate that the organic material sandwiched between aragonite platelets consists of multiple organic layers of varying nano-mechanical resilience. Based on these novel observations and analysis, we propose a spiral growth model that accounts for both [001] vertical propagation via helices that surround numerous screw dislocation cores and simultaneous 〈010〉 lateral growth of aragonite sheet structure. These new findings may aid in creating novel organic–inorganic micro/nano composites through synthetic or biomineralization pathways

a global network of chronic kidney disease cohorts

Background Chronic kidney disease (CKD) is a global health burden, yet it is still underrepresented within public health agendas in many countries. Studies focusing on the natural history of CKD are challenging to design and conduct, because of the long time-course of disease progression, a wide variation in etiologies, and a large amount of clinical variability among individuals with CKD. With the difference in health-related behaviors, healthcare delivery, genetics, and environmental exposures, this variability is greater across countries than within one locale and may not be captured effectively in a single study. Methods Studies were invited to join the network. Prerequisites for membership included: 1) observational designs with a priori hypotheses and defined study objectives, patient-level information, prospective data acquisition and collection of bio-samples, all focused on predialysis CKD patients; 2) target sample sizes of 1,000 patients for adult cohorts and 300 for pediatric cohorts; and 3) minimum follow-up of three years. Participating studies were surveyed regarding design, data, and biosample resources. Results Twelve prospective cohort studies and two registries covering 21 countries were included. Participants age ranges from >2 to >70 years at inclusion, CKD severity ranges from stage 2 to stage 5. Patient data and biosamples (not available in the registry studies) are measured yearly or biennially. Many studies included multiple ethnicities; cohort size ranges from 400 to more than 13,000 participants. Studies’ areas of emphasis all include but are not limited to renal outcomes, such as progression to ESRD and death. Conclusions iNET-CKD (International Network of CKD cohort studies) was established, to promote collaborative research, foster exchange of expertise, and create opportunities for research training. Participating studies have many commonalities that will facilitate comparative research; however, we also observed substantial differences. The diversity we observed across studies within this network will be able to be leveraged to identify genetic, behavioral, and health services factors associated with the course of CKD. With an emerging infrastructure to facilitate interactions among the investigators of iNET-CKD and a broadly defined research agenda, we are confident that there will be great opportunity for productive collaborative investigations involving cohorts of individuals with CKD

GrassPlot v. 2.00 – first update on the database of multi-scale plant diversity in Palaearctic grasslands

Abstract: GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). Following a previous Long Database Report (Dengler et al. 2018, Phyto- coenologia 48, 331–347), we provide here the first update on content and functionality of GrassPlot. The current version (GrassPlot v. 2.00) contains a total of 190,673 plots of different grain sizes across 28,171 independent plots, with 4,654 nested-plot series including at least four grain sizes. The database has improved its content as well as its functionality, including addition and harmonization of header data (land use, information on nestedness, structure and ecology) and preparation of species composition data. Currently, GrassPlot data are intensively used for broad-scale analyses of different aspects of alpha and beta diversity in grassland ecosystems

Kafka at the West Bank checkpoint: de-normalizing the Palestinian encounter before the law

The checkpoint has emerged as a quintessential trope within the contemporary Palestinian imagination, to such an extent that “checkpoint narratives” have arguably come to assume a dangerously “normalized” status as everyday, even iconic features of Palestinian existence. Turning to the films Route 181 by Michel Khleifi and Eyal Sivan, and like twenty impossibles by Annemarie Jacir, this article explores how alternative representations (and theorizations) of checkpoint encounter might serve to “de-normalize” the checkpoint in a way that invites us to interrogate the very nature of the checkpoint apparatus in itself, including the nature of the “law” that it represents. Mobilizing the critical paradigms of the “state of exception” and “homo sacer” drawn from the theoretical work of Giorgio Agamben and the literary work of Franz Kafka, the article argues that apprehension of the enduring oddity and abnormality of the checkpoint serves as a vital mode of critical resistance to the policies of “spatio-cide”, “securitization” and colonialism exercised at the hands of the State of Israel through the checkpoint mechanism

Re:Chicago

https://via.library.depaul.edu/museum-publications/1012/thumbnail.jp

Regional variation in hemoglobin distribution among individuals with chronic kidney disease: the ISN International Network of Chronic Kidney Disease (iNET-CKD) Cohorts

Introduction: Despite recognized geographic and sex-based differences in hemoglobin in the general population, these factors are typically ignored in patients with chronic kidney disease (CKD) in whom a single therapeutic range for hemoglobin is recommended. We sought to compare the distribution of hemoglobin across international nondialysis CKD populations and evaluate predictors of hemoglobin.Methods: In this cross-sectional study, hemoglobin distribution was evaluated in each cohort overall and stratified by sex and estimated glomerular filtration rate (eGFR). Relationships between candidate predictors and hemoglobin were assessed from linear regression models in each cohort. Estimates were subsequently pooled in a random effects model.Results: A total of 58,613 participants from 21 adult cohorts (median eGFR range of 17–49 ml/min) and 3 pediatric cohorts (median eGFR range of 26–45 ml/min) were included with broad geographic representation. Hemoglobin values varied substantially among the cohorts, overall and within eGFR categories, with particularly low mean hemoglobin observed in women from Asian and African cohorts. Across the eGFR range, women had a lower hemoglobin compared to men, even at an eGFR of 15 ml/min (mean difference 5.3 g/l, 95% confidence interval [CI] 3.7–6.9). Lower eGFR, female sex, older age, lower body mass index, and diabetic kidney disease were all independent predictors of a lower hemoglobin value; however, this only explained a minority of variance (R2 7%–44% across cohorts).Conclusion: There are substantial regional differences in hemoglobin distribution among individuals with CKD, and the majority of variance is unexplained by demographics, eGFR, or comorbidities. These findings call for a renewed interest in improving our understanding of hemoglobin determinants in specific CKD populations.</p

IGEMS: The Consortium on Interplay of Genes and Environment Across Multiple Studies

The Interplay of Genes and Environment across Multiple Studies (IGEMS) group is a consortium of eight longitudinal twin studies established to explore the nature of social context effects and gene-environment interplay in late-life functioning. The resulting analysis of the combined data from over 17,500 participants aged 25–102 at baseline (including nearly 2,600 monogygotic and 4,300 dizygotic twin pairs and over 1,700 family members) aims to understand why early life adversity, and social factors such as isolation and loneliness, are associated with diverse outcomes including mortality, physical functioning (health, functional ability), and psychological functioning (well-being, cognition), particularly in later life

Expansion of Signal Transduction Pathways in Fungi by Extensive Genome Duplication

International audienceno abstrac

Genetic and environmental influences on human height from infancy through adulthood at different levels of parental education

Genetic factors explain a major proportion of human height variation, but differences in mean stature have also been found between socio-economic categories suggesting a possible effect of environment. By utilizing a classical twin design which allows decomposing the variation of height into genetic and environmental components, we tested the hypothesis that environmental variation in height is greater in offspring of lower educated parents. Twin data from 29 cohorts including 65,978 complete twin pairs with information on height at ages 1 to 69 years and on parental education were pooled allowing the analyses at different ages and in three geographic-cultural regions (Europe, North America and Australia, and East Asia). Parental education mostly showed a positive association with offspring height, with significant associations in mid-childhood and from adolescence onwards. In variance decomposition modeling, the genetic and environmental variance components of height did not show a consistent relation to parental education. A random-effects meta-regression analysis of the aggregate-level data showed a trend towards greater shared environmental variation of height in low parental education families. In conclusion, in our very large dataset from twin cohorts around the globe, these results provide only weak evidence for the study hypothesis.Peer reviewe