In this article we study the deformations of hyperelliptic polarized varieties (X, L) of dimension m and sectional genus g such that the image Y of the morphism ϕ induced by |L| is smooth. If L m < 2g − 2, it is known that, by adjunction and the Clifford's theorem, any deformation of (X, L) is hyperelliptic. Thus, we focus on when L m = 2g − 2 or L m = 2g. We prove that, if (X, L) is Fano-K3, then, except when Y is a hyperquadric, all deformations of (X, L) are again hyperelliptic (if Y is a hyperquadric, the general deformation of ϕ is an embedding). This contrasts with the situation of hyperelliptic canonical curves and hyperelliptic K3 surfaces. If L m = 2g, then we prove that, in most cases, a general deformation of ϕ is a finite morphism of degree 1. This provides interesting examples of degree 2 morphisms that can be deformed to morphisms of degree 1. We extend our results to so-called generalized hyperelliptic polarized Fano, Calabi-Yau and general type varieties. The solutions to these questions are closely intertwined with the existence or non existence of double structures on the algebraic varieties Y . We address this matter as well.

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El cobre se obtiene principalmente a partir de los sulfuros de cobre, mediante procesos clásicos de flotación y pirometalúrgicos, siendo Chile el mayor productor de cobre en el mundo. En nuestro país existen siete fundiciones de cobre que generan grandes volúmenes de escoria. Este trabajo presenta los resultados obtenidos de la flotación de cobre de escorias del horno de reverbero (HR) y del convertidor Teniente (CT) de la Fundición Hernán Videla Lira-Paipote. Así, mediante pruebas de flotación rougher, a escala de laboratorio, se determinó que la granulometría, para ambos casos, corresponde a 70% menor a 74 µm, lográndose recuperaciones de 59,2% escoria HR y 86,8% para la escoria del CT, cuyas leyes de cobre en el concentrado fueron de 3,7% y 23,6% respectivamente. Las dosis de reactivos utilizados fueron 40 g/t de F-703 como colector y 30 g/t de H-70 como espumante. Los tiempos óptimos de flotación de las etapas rougher y cleaner, de ambas escorias, se determinaron mediante cinéticas de flotación. Finalmente se realizaron pruebas a nivel industrial con los resultados de laboratorio, alcanzándose una ley de 18,2% de cobre (recuperación de 56,1%) para escoria HR, mientras que para la escoria CT se obtuvo una ley de 39,1% de cobre con una recuperación de 91,4% PALABRAS-CLAVE: escoria de cobre, recuperación, flotación.

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Burn prevention information may be inadequate or inaccessible to communities with non-English language preference. Our objective was to systematically analyze the content accuracy, website quality, and readability of online Spanish information for burn prevention in the home and compare it to English websites. We collected the top ten burn prevention results from a search on Google, Bing, and Yahoo using a list of Spanish key terms. Using recommendations from national organizations and a burn care expert team, content accuracy was evaluated for each website. We assessed website quality following the “Health on the Net” Code of Conduct. Readability was scored by averaging five validated readability tests for the Spanish language. After using the same protocol, a comparison was made with English websites as a control. Once duplicates and non-relevant search results were removed, 23 Spanish websites were assessed. Out of 21 possible points for content accuracy, the top website scored 14 (67%) and the average score was 6.6 (31%). For website quality, the average score was 50%. The average grade level needed to read the websites was 8.6. Compared to English, Spanish websites were less accurate (31% vs 41%), harder to read (9.8 vs 7.8), but were of higher website quality (50% vs 43%). Online burn prevention information in Spanish is often inaccurate, incomplete, and inferior to available English language websites. We propose a call to action to increase the quality of online burn prevention material available in Spanish.

Introduction Many burn injuries are preventable, yet burn prevention information may be inadequate or inaccessible to communities with non-English language preference. Out of the estimated 480,000 people in the US that are treated annually for burns, 14% identify as Latinx. Among the 60 million Latinx individuals living in the US, 33% report limited English proficiency. As a result, many Latinx persons rely on health information in Spanish. The availability and quality of Spanish language information regarding burn prevention has not previously been studied but presents an important opportunity to reduce burn-related injuries for the US Latinx population. Our objective was to systematically analyze the content accuracy, website quality, and readability of Spanish language online information for burn prevention in the home. Methods We conducted a search on Google, Bing, and Yahoo using the following key burn prevention terms in Spanish: “prevención de quemaduras,” “prevenir quemaduras,” “evitar quemaduras,” and “impedir quemaduras”. The top 10 results from each search engine and key term were recorded. Using recommendations from national organizations and a burn care expert team, two reviewers independently evaluated the content accuracy of each website and met to reach consensus. We assessed website quality by three major categories based on the Health on the Net Code of Conduct (HONcode): accessibility/usability, credibility, and currency. We scored readability of each website by utilizing five validated readability tests for the Spanish language and generating an average grade reading level needed to understand the article. Results After removing duplicates and irrelevant search results, 23 websites in Spanish met inclusion criteria. Across all websites, the content accuracy of information broken down by type of burn was as follows: scald 35%, electrical 28%, contact 20%, and flame 17%. Out of 21 possible points, the top website scored 14 (66.7%) and the average score was 6.6 (31.4%). Using the intraclass correlation coefficients, the interrater reliability was 0.935. For website quality, the average score was 50.2%. The average grade level needed to read the websites was 8.6. Conclusions Spanish language online information on burn prevention in the home is often inaccurate and incomplete. Furthermore, overall website quality was lower than 50% according to the HONcode, and the average grade level needed to read the articles is higher than the sixth-grade recommendation from the American Medical Association. Applicability of Research to Practice This research highlights the lack of reliable and accessible information in Spanish on home burn prevention. Not only does this research suggest that Spanish-speaking patients should be provided education on burn prevention by their healthcare providers, but more importantly, we propose a call to action to increase the quality of online Spanish materials for burn prevention for the US Latinx community.

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