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.

Biological agents as weapons of agro‐crime or agro‐terrorism pose threats to peace and economic stability. Such agents pre‐exist worldwide as hazards, adversely affecting animal health, as well as imposing substantial burdens on many nations. Few studies have quantified the global risks and vulnerabilities of countries and regions to potential terrorist or criminal operations targeting animal health. We present here a risk‐based mutual insurance premium framework for animal health outcomes built upon the World Organisation for Animal Health (WOAH) quantitative risk assessment paradigm. Our objective was to generate dimensionless and relative domain indices related to release and exposure for several biological factors, as well as to assess the preparedness and response ability of each country. We also considered disease‐specific measures relating to pathogens, targeted animal populations, the ongoing disease situation, within‐ and among‐country peace or conflict, disease‐specific control measures, and the availability of technical tools and personnel for successful disease management. National economic, political, and research and development competencies were used to assess each WOAH Member's potential for resilience. We formulated indices of vulnerability for 25 WOAH Members selected from five worldwide regions; initially, against four transboundary infectious animal diseases that target diverse animal species. We developed these indices using variables obtained from public databases arising from multiple intergovernmental organizations. Subsequently, we compared the relative vulnerability indices among countries for each given disease using three different index building methods: arithmetic mean, distance matrix, and principal component analysis (PCA). The PCA‐based approach provided the greatest ability to discriminate among the components and among countries and regions. Due to its transparency and reliance on publicly available datasets, the risk premium framework proposed herein may readily be adjusted by policymakers and agencies and utilized to improve risk management strategies against agro‐crime or agro‐terror events, as well as for unintentional disease introductions.

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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.

Research in EMG-based control of prostheses has mainly utilized adult subjects who have fully developed neuromuscular control. Little is known about children's ability to generate consistent EMG signals necessary to control artificial limbs with multiple degrees of freedom. As a first step to address this gap, experiments were designed to validate and benchmark two experimental protocols that quantify the ability to coordinate forearm muscle contractions in typically developing children. Non-disabled, healthy adults and children participated in our experiments that aimed to measure an individual's ability to use myoelectric control interfaces. In the first experiment, participants performed 8 repetitions of 16 different hand/wrist movements. Using offline classification analysis based on Support VectorMachine, we quantified their ability to consistently produce distinguishable muscle contraction patterns. We demonstrated that children had a smaller number of highly independent movements (can be classified with > 90% accuracy) than adults did. The second experiment measured participants' ability to control the position of a cursor on a 1-DoF virtual slide using proportional EMG control with three different visuomotor gain levels. We found that children had higher failure rates and slower average target acquisitions than adults did, primarily due to longer correction times that did not improve over repetitive practice. We also found that the performance in both experiments was age-dependent in children. The results of this study provide novel insights into the technical and empirical basis to better understand neuromuscular development in children with upper-limb loss.