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In high density, high temperature plasmas, the plasma sheath that develops can result in extremely high electric fields, on the order of tens to hundreds of V/nm. Under the right conditions, these electric fields can reach magnitudes that can increase the probability of electron tunneling ionization to occur, resulting in one or more electron-ion pairs. The presence of tunneling ionization can then modify the development of the plasma sheath, as well as properties such as the ion and electron densities and plasma potential. The tunnel ionization process for hydrogen atoms is demonstrated, in this work, as implemented in a Sandia National Laboratories, particle-in-cell code Aleph. Results are presented for the application of the tunnel ionization process to a one-dimensional, undriven plasma sheath. Additional results for cases that consider warm ions and neutrals, the inclusion of electron–neutral collisions, and the injection of neutral particles, as well as the application to various plasma devices, will be discussed.

Silicon-vacancy centres in diamond are promising candidates as emitters in photonic quantum networks, but their coherence is degraded by large electron-phonon interactions. Sohn et al. demonstrate the use of strain to tune a silicon vacancy’s electronic structure and suppress phonon-mediated decoherence.

Interfacing spin quantum memories with photons requires the controlled creation of defect centre—nanocavity systems. Here the authors demonstrate direct, maskless creation of single silicon vacancy centres in diamond nanostructures, and report linewidths comparable to naturally occurring centres

Desde una perspectiva bioantropológica, las mediciones antropométricas en adultos son exhaustivamente utilizadas en la evaluación morfológica de poblaciones argentinas extintas. La mayoría de los estudios antropométricos en adultos argentinos contemporáneos se limitan a la evaluación de talla, peso e IMC. El objetivo de este trabajo fue describir otras variables antropométricas en adultos del Noroeste argentino (NOA) y compararlas con una referencia internacional. Los datos de peso, talla, perímetros (brazo, muslo, pierna, cintura) y pliegues (tríceps, subescapular) proceden de 881 individuos (526 mujeres; 355 varones) sanos de 20-60 años de edad de distintas localidades de Catamarca y Jujuy. Se calcularon estadísticos descriptivos (media y DS) por sexo y dos grupos de edad: 20-39 y 40-60 años. Las comparaciones se establecieron con adultos de EEUU de origen mejicano (Centers for Disease Control, CDC 2003-2006) con la prueba t. Se calcularon los percentilos con el método LMS. En ambos sexos y grupos de edad los adultos del NOA presentaron valores significativamente inferiores a los de la referencia en todas las variables consideradas, excepto para pliegues tricipital y subescapular en varones de 40-60 años. No se han encontrado antecedentes antropométricos comparables semejantes para poblaciones argentinas y del NOA. El perfil antropométrico de los adultos del NOA difiere significativamente con respecto a la población de referencia con un origen étnico afín. Palabras clave: adultos; Noroeste Argentino; perímetros; pliegues; antropometría From a bioanthropological point of view, anthropometric measurements in adults are extensively used in the morphological evaluation of extinct Argentine populations. Most anthropometric studies in contemporary Argentine adults are limited to the assessment of height, weight and BMI. The aim of this study was to describe other anthropometric variables in northwestern Argentine (NWA) adults and to compare them with an international reference. Data on weight, height, circumferences (arm, thigh, leg, waist), and skinfolds (triceps, subscapular) come from 881 (526 women, 355 men) 20-60 year-old healthy individuals from different localities ofJujuy and Catamarca. Descriptive statistics (mean and SD) were calculated by sex and two age groups: 20-39 and 40-60 years. Comparisons were made with adults of Mexican origin from theUnited States (Centers for Disease Control, CDC 2003-2006) using the t-test. Percentiles were calculated using the LMS method. In both sexes and age groups NWA adults presented significantly lower values than those of the reference group in all the variables considered, except for triceps and subscapular skinfolds in males of 40-60 years old. There are no comparable anthropometric records for Argentine and NWA populations. The anthropometric profile of NWA adults differs significantly from that of the ethnically related reference population. Keyswords: adults; Argentine Northwest; circumferences; skinfold thickness; anthropometry