2,974 research outputs found

    Adventures in Lunar Core Processing: Timeline of and Preparation for Opening of Core Sample 73002 for the ANGSA Program

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    The Apollo mission returned 382 kg of rocks, soil and core samples, which have helped to advance our knowledge of lunar science. Studies of these lunar samples are crucial for our understanding of the Moons geological evolution. Here, we present the meticulous process that involves preparing for, and ultimately opening, the unopened Apollo 17 drive tube: 73002,0, so that the next generation of lunar scientists can further our insight into the Moons history

    Chromosome Evolution in Cyperales

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    Karyotypic evolution is a prominent feature in the diversification of many plants and animals, yet the role that chromosomal changes play in the process of diversification is still debated. At the diploid level, chromosome fission and/or fusion are necessary components of chromosomal structural change associated with diversification. Yet the genomic features required for these events remain unknown. Here we present an overview of what is known about genomic structure in Cyperales, with particular focus on the current level of understanding of chromosome number and genome size and their impact in a phylogenetic context. We outline ongoing projects exploring genomic structure in the order using modern genomics techniques coupled with traditional data sets. Additionally, we explore the questions to which this approach might be best applied, and in particular, detail a project exploring the nature of genomic structural change at the diploid level in genus Carex, a group in which chromosome fission/fusion events are common and associated with diversification of many of its 2000 species. A hypothesized mechanism for chromosome number change in this genus is agmatoploidy, denoting changes in chromosome number without change in DNA amount through fission/fusion of holocentric chromosomes (chromosomes without localized centromeres). This project includes the creation of bacterial artificial chromosome (BAC) and expressed sequence tagged (EST) libraries to be used in physical and genetic linkage mapping studies in order to reveal the patterns of genome structural variation associated with agmatoploidy in Carex, and to explore the sequence and genic characteristics of chromosomal break points in the genome

    Metamorphism on Ordinary Chondrite Parent Bodies: The Role of Fluids.

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    第3回極域科学シンポジウム/第35回南極隕石シンポジウム 11月30日(金) 国立国語研究所 2階講

    Adaptation and validation of the Inventory of family protective factors for the portuguese culture

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    Aim: Describe the process of cultural adaptation and validation of Inventory of Family Protective Factors (IFPF) for portuguese culture. This instrument assesses the protective factors that contribute to family resilience. Studies of resilience fall the salutogenic paradigm, which focuses on protective factors of individuals or groups, without minimizing the risk factors and vulnerability. Methods: We applied this instrument to 85 families of children with special needs and, after linguistic and conceptual equivalence, used an exploratory factor analysis with principal components analysis (with varimax rotation) and calculated the Cronbach's alpha coefficient for each dimension. Results: adequate psychometric properties to be used in Portuguese population (Cronbach´s alpha =.90). Conclusion: IFPF is an useful instrument for studies which propose assess the protective factors of family resilience, however we suggest further studies of revalidation.Objetivo: Describir el proceso de adaptación cultural y validación para la cultura portuguesa de Inventory of Family Protective Factors (IFPF). Este instrumento evalúa los factores de protección que contribuyan a la resiliencia familiar. Estudios de resiliência familiar se apoyan en el paradigma salutogénico, que se centra en los factores de protección de individuos o grupos, sin subestimar los factores de riesgo y vulnerabilidad. Metodologia: Aplicamos este instrumento a 85 familias de niños con necesidades especiales y, después de la equivalencia lingüística y conceptual, hemos llevado a cabo un análisis factorial exploratorio de componentes principales con rotación varimax y calculamos el coeficiente alfa de Cronbach. Resultados: la IFPF tiene adecuadas propiedades psicométricas para la población portuguesa (alfa de Cronbach = .90). Conclusion: Esta es una herramienta útil para evaluar los factores protectores de la resiliencia familiar, sin embargo sugerimos estudios futuros de revalidación.Objetivos: adaptar e validar o Inventory of Family Protective Factors (IFPF) para a cultura portuguesa. Este instrumento avalia os fatores protetores que contribuem para a resiliência familiar. Os estudos sobre resiliência inserem-se no paradigma salutogénico, abordando os fatores protetores dos indivíduos ou grupos, sem subestimar os fatores de risco ou vulnerabilidade. Método: para avaliar a equivalência linguística e conceitual do IFPF realizamos a tradução, retroversão e reflexão falada; para aferir as características psicométricas do instrumento verificamos a sensibilidade, confiabilidade e a validade dos resultados. Realizamos uma análise fatorial de componentes principais com rotação varimax dos itens da escala e calculamos o coeficiente Alpha de Cronbach para cada dimensão. Através de uma amostragem aleatória simples, aplicamos este instrumento a 85 famílias de crianças com necessidades especiais que o auto-preencheram. Resultados: o IFPF apresenta características psicométricas adequadas para a população portuguesa (alfa de Cronbach de .90). Conclusão: o IFPF foi adaptado e validado para a cultura portuguesa. Consideramos tratar-se de um instrumento útil para estudos que se proponham avaliar os fatores protetores da resiliência familiar

    A review of volatiles in the Martian interior

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    Multiple observations from missions to Mars have revealed compelling evidence for a volatile-rich Martian crust. A leading theory contends that eruption of basaltic magmas was the ultimate mechanism of transfer of volatiles from the mantle toward the surface after an initial outgassing related to the crystallization of a magma ocean. However, the concentrations of volatile species in ascending magmas and in their mantle source regions are highly uncertain. This work and this special issue of Meteoritics & Planetary Science summarize the key findings of the workshop on Volatiles in the Martian Interior (Nov. 3–4, 2014), the primary open questions related to volatiles in Martian magmas and their source regions, and the suggestions of the community at the workshop to address these open questions

    Multiple reservoirs of volatiles in the Moon revealed by the isotopic composition of chlorine in lunar basalts

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    The isotopes of chlorine (37Cl and 35Cl) are highly fractionated in lunar samples compared to most other Solar System materials. Recently, the chlorine isotope signatures of lunar rocks have been attributed to large-scale degassing processes that occurred during the existence of a magma ocean. In this study we investigated how well a suite of lunar basalts, most of which have not previously been analyzed, conform to previous models. The Cl isotope compositions (δ37Cl (‰) = [(37Cl/35Clsample/37Cl/35ClSMOC)-1]×1000, where SMOC refers to standard mean ocean chloride) recorded range from ∼+7 to +14 ‰ (Apollo 15), +10 to +19 ‰ (Apollo 12), +9 to +15 ‰ (70017), +4 to +8 ‰ (MIL 05035), and +15 to +22 ‰ (Kalahari 009). The Cl isotopic data from the present study support the mixing trends previously reported by Boyce et al., 2015, Barnes et al., 2016, as the Cl isotopic composition of apatites are positively correlated with bulk-rock incompatible trace element abundances in the low-Ti basalts, inclusive of low-Ti and KREEP basalts. This trend has been interpreted as evidence that incompatible trace elements, including Cl, were concentrated in the urKREEP residual liquid of the lunar magma ocean, rather than the mantle cumulates, and that urKREEP Cl had a highly fractionated isotopic composition. The source regions for the basalts were thus created by variable mixing between the mantle (Cl-poor and relatively unfractionated) and urKREEP. The high-Ti basalts show much more variability in measured Cl isotope ratios and scatter around the trend formed by the low-Ti basalts. Most of the data for lunar meteorites also fits the mixing of volatiles in their sources, but Kalahari 009, which is highly depleted in incompatible trace elements, contains apatites with heavily fractionated Cl isotopic compositions. Given that Kalahari 009 is one of the oldest lunar basalts and ought to have been derived from very early-formed mantle cumulates, a heavy Cl isotopic signature is likely not related to its mantle source, but more likely to magmatic or secondary alteration processes, perhaps via impact-driven vapor metasomatism of the lunar crust

    Investigating Astromaterials Curation Applications for Dexterous Robotic Arms

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    The Astromaterials Acquisition and Curation office at NASA Johnson Space Center is currently investigating tools and methods that will enable the curation of future astromaterials collections. Size and temperature constraints for astromaterials to be collected by current and future proposed missions will require the development of new robotic sample and tool handling capabilities. NASA Curation has investigated the application of robot arms in the past, and robotic 3-axis micromanipulators are currently in use for small particle curation in the Stardust and Cosmic Dust laboratories. While 3-axis micromanipulators have been extremely successful for activities involving the transfer of isolated particles in the 5-20 micron range (e.g. from microscope slide to epoxy bullet tip, beryllium SEM disk), their limited ranges of motion and lack of yaw, pitch, and roll degrees of freedom restrict their utility in other applications. For instance, curators removing particles from cosmic dust collectors by hand often employ scooping and rotating motions to successfully free trapped particles from the silicone oil coatings. Similar scooping and rotating motions are also employed when isolating a specific particle of interest from an aliquot of crushed meteorite. While cosmic dust curators have been remarkably successful with these kinds of particle manipulations using handheld tools, operator fatigue limits the number of particles that can be removed during a given extraction session. The challenges for curation of small particles will be exacerbated by mission requirements that samples be processed in N2 sample cabinets (i.e. gloveboxes). We have been investigating the use of compact robot arms to facilitate sample handling within gloveboxes. Six-axis robot arms potentially have applications beyond small particle manipulation. For instance, future sample return missions may involve biologically sensitive astromaterials that can be easily compromised by physical interaction with a curator; other potential future returned samples may require cryogenic curation. Robot arms may be combined with high resolution cameras within a sample cabinet and controlled remotely by curator. Sophisticated robot arm and hand combination systems can be programmed to mimic the movements of a curator wearing a data glove; successful implementation of such a system may ultimately allow a curator to virtually operate in a nitrogen, cryogenic, or biologically sensitive environment with dexterity comparable to that of a curator physically handling samples in a glove box

    Review of ATLAS Software Documentation (February 8-9, 2006)

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    Review of the ATLAS Offline Documentation: Web pages, WorkBook, TWiki, HyperNews, Doxygen

    The Astromaterials X-Ray Computed Tomography Laboratory at Johnson Space Center

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    The Astromaterials Acquisition and Cura-tion Office at NASA's Johnson Space Center (hereafter JSC curation) is the past, present, and future home of all of NASA's astromaterials sample collections. JSC curation currently houses all or part of nine different sample collections. Our primary goals are to maintain the long-term integrity of the samples and ensure that the samples are distributed for scientific study in a fair, timely, and responsible manner, thus maximizing the return on each sample. Part of the curation process is planning for the future, thus we also perform funda-mental research in advanced curation initiatives. Ad-vanced Curation is tasked with developing procedures, technology, and data sets necessary for curating new types of sample collections, or getting new results from existing sample collections [1]. As part of these ad-vanced curation efforts we are augmenting our analyti-cal facilities

    Meca500 Robotic Arm Developments Towards Astromaterials Curation Applications

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    As a part of the ongoing efforts to develop new curation tools and techniques for astromaterials within the Astromaterials Acquisition and Curation office at NASAs Johnson Space Center, we are developing a variety of manually and electrically controlled micromanipulation systems. Most current techniques require manual manipulation, and in some cases the manipulation task is being done entirely freehand. The motorized systems avail-able are restricted to three degrees of freedom and use proprietary control systems. For example, the MicroSupport AxisPro manipulation system currently used in microscale particle experiments is limited in its range of motion, as it can only move the manipulators in a three axis Cartesian range over a predetermined area above microscope slides. While having an efficient user interface, the control system is proprietary and prevents custom development and optimization to extend the viable applications of the system. In order to address some of these limitations, we have been testing robotic designs with multiple degrees of freedom and of a variety of designs. We are currently investigating the Meca500 robotic arm by Mecademic as a potential manipulation system to overcome some of these obstacles
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