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2.
Pharmacoecon Open ; 4(1): 71-77, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31123931

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer in the USA. Its economic impact is extensive, and preventive screening services are warranted to help prevent it. OBJECTIVE: We sought to examine the return on investment, in terms of reduced costs attributed to cancer prevention, of a CRC screening outreach program providing education and screening in a primarily rural region targeting the uninsured and underinsured. METHODS: The expenditures of the Northeast Texas CRC screening program were calculated for the years of 2016 and 2017. Prices ($US) were adjusted for inflation and converted to year 2017 values. The costs saved were calculated using the estimated costs of CRC care present in the literature. RESULTS: For fiscal years 2016 and 2017, the program provided an average return of $US1.46-2.06 for every tax dollar spent. Estimated cost avoidance was $US165,080 per avoided case and estimated cost avoidance of $US245,601 among early-stage cancer cases detected, resulting in potential savings ranging from $US3,893,676 to $US4,837,923. CONCLUSION: A CRC outreach program providing education and screening operating in less densely populated regions yields a positive return on investment.

3.
J Immigr Minor Health ; 21(5): 931-937, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30099665

RESUMO

Colorectal cancer is the fourth most frequently diagnosed cancer. However, due to variations in diet, it was hypothesized that risk of adenomatous or hyperplastic polyps or malignancies would be lower among Hispanics. Participants (n = 1671) underwent a colonoscopy. Results were grouped into one of four groups: normal, hyperplastic polyps only, adenomatous polyps, and malignancies. As expected, Hispanics had a lower risk of hyperplastic (p = .031, OR = 0.47) and adenomatous polyps (p = .031, OR = 0.66) than non-Hispanic Whites. Comparison between malignancies was not possible as no Hispanics had a malignancy. Contrary to expectations, risk of hyperplastic and adenomatous polyps and malignancies were no different between non-Hispanic Blacks and Whites. Among rural and mostly rural populations, Hispanics had a lower risk of hyperplastic and adenomatous polyps.


Assuntos
Pólipos do Colo/diagnóstico , Hispânico ou Latino , População Rural , Pólipos Adenomatosos/diagnóstico , Pólipos Adenomatosos/epidemiologia , Idoso , Pólipos do Colo/epidemiologia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Astrobiology ; 3(4): 739-58, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14987479

RESUMO

The discovery of evidence indicative of life in a Martian meteorite has led to an increase in interest in astrobiology. As a result of this discovery, and the ensuing controversy, it has become apparent that our knowledge of the early development of life on Earth is limited. Archean stratigraphic successions containing evidence of Earth's early biosphere are well preserved in the Pilbara Craton of Western Australia. The craton includes part of a protocontinent consisting of granitoid complexes that were emplaced into, and overlain by, a 3.51-2.94 Ga volcanigenic carapace - the Pilbara Supergroup. The craton is overlain by younger supracrustal basins that form a time series recording Earth history from approximately 2.8 Ga to approximately 1.9 Ga. It is proposed that a well-documented suite of these ancient rocks be collected as reference material for Archean and astrobiological research. All samples would be collected in a well-defined geological context in order to build a framework to test models for the early evolution of life on Earth and to develop protocols for the search for life on other planets.


Assuntos
Archaea , Planeta Terra , Evolução Planetária , Exobiologia/métodos , Austrália , Evolução Biológica , Fósseis , Origem da Vida , Paleontologia , Dióxido de Silício , Fatores de Tempo
5.
Astrobiology ; 3(3): 583-96, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14678667

RESUMO

Unique springs, discharging from the surface of an arctic glacier, release H(2)S and deposit native sulfur, gypsum, and calcite. The presence of sulfur in three oxidation states indicates a complex series of redox reactions. Physical and chemical conditions of the spring water and surrounding environment, as well as mineralogical and isotopic signatures, suggest biologically mediated reactions. Cell counts and DNA analyses confirm bacteria are present in the spring system, and a limited number of sequenced isolates suggests that complex communities of bacteria live within the glacial system.


Assuntos
Clima Frio , Gelo , Vida , Enxofre/análise , Água , Regiões Árticas , DNA/genética , DNA/isolamento & purificação , Primers do DNA , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Microscopia Eletrônica de Varredura , Oxirredução , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação
6.
Science ; 345(6198): 786-91, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25124433

RESUMO

Seven particles captured by the Stardust Interstellar Dust Collector and returned to Earth for laboratory analysis have features consistent with an origin in the contemporary interstellar dust stream. More than 50 spacecraft debris particles were also identified. The interstellar dust candidates are readily distinguished from debris impacts on the basis of elemental composition and/or impact trajectory. The seven candidate interstellar particles are diverse in elemental composition, crystal structure, and size. The presence of crystalline grains and multiple iron-bearing phases, including sulfide, in some particles indicates that individual interstellar particles diverge from any one representative model of interstellar dust inferred from astronomical observations and theory.

7.
Astrobiology ; 12(6): 601-15, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22731685

RESUMO

This paper presents the hypothesis that the well-known giant polygons and bright mounds of the martian lowlands may be related to a common process-a process of fluid expulsion that results from burial of fine-grained sediments beneath a body of water. Specifically, we hypothesize that giant polygons and mounds in Chryse and Acidalia Planitiae are analogous to kilometer-scale polygons and mud volcanoes in terrestrial, marine basins and that the co-occurrence of masses of these features in Chryse and Acidalia may be the signature of sedimentary processes in an ancient martian ocean. We base this hypothesis on recent data from both Earth and Mars. On Earth, 3-D seismic data illustrate kilometer-scale polygons that may be analogous to the giant polygons on Mars. The terrestrial polygons form in fine-grained sediments that have been deposited and buried in passive-margin, marine settings. These polygons are thought to result from compaction/dewatering, and they are commonly associated with fluid expulsion features, such as mud volcanoes. On Mars, in Chryse and Acidalia Planitiae, orbital data demonstrate that giant polygons and mounds have overlapping spatial distributions. There, each set of features occurs within a geological setting that is seemingly analogous to that of the terrestrial, kilometer-scale polygons (broad basin of deposition, predicted fine-grained sediments, and lack of significant horizontal stress). Regionally, the martian polygons and mounds both show a correlation to elevation, as if their formation were related to past water levels. Although these observations are based on older data with incomplete coverage, a similar correlation to elevation has been established in one local area studied in detail with newer higher-resolution data. Further mapping with the latest data sets should more clearly elucidate the relationship(s) of the polygons and mounds to elevation over the entire Chryse-Acidalia region and thereby provide more insight into this hypothesis.


Assuntos
Mapeamento Geográfico , Marte , Oceanos e Mares , Planeta Terra , Meio Ambiente Extraterreno , Sedimentos Geológicos , Fenômenos Geológicos , Água
8.
Science ; 329(5998): 1510-3, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20847267

RESUMO

Using data from the Diviner Lunar Radiometer Experiment, we show that four regions of the Moon previously described as "red spots" exhibit mid-infrared spectra best explained by quartz, silica-rich glass, or alkali feldspar. These lithologies are consistent with evolved rocks similar to lunar granites in the Apollo samples. The spectral character of these spots is distinct from surrounding mare and highlands material and from regions composed of pure plagioclase feldspar. The variety of landforms associated with the silicic spectral character suggests that both extrusive and intrusive silicic magmatism occurred on the Moon. Basaltic underplating is the preferred mechanism for silicic magma generation, leading to the formation of extrusive landforms. This mechanism or silicate liquid immiscibility could lead to the formation of intrusive bodies.

9.
Science ; 329(5998): 1507-9, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20847266

RESUMO

We obtained direct global measurements of the lunar surface using multispectral thermal emission mapping with the Lunar Reconnaissance Orbiter Diviner Lunar Radiometer Experiment. Most lunar terrains have spectral signatures that are consistent with known lunar anorthosite and basalt compositions. However, the data have also revealed the presence of highly evolved, silica-rich lunar soils in kilometer-scale and larger exposures, expanded the compositional range of the anorthosites that dominate the lunar crust, and shown that pristine lunar mantle is not exposed at the lunar surface at the kilometer scale. Together, these observations provide compelling evidence that the Moon is a complex body that has experienced a diverse set of igneous processes.

10.
Science ; 330(6003): 479-82, 2010 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-20966246

RESUMO

Diviner Lunar Radiometer Experiment surface-temperature maps reveal the existence of widespread surface and near-surface cryogenic regions that extend beyond the boundaries of persistent shadow. The Lunar Crater Observation and Sensing Satellite (LCROSS) struck one of the coldest of these regions, where subsurface temperatures are estimated to be 38 kelvin. Large areas of the lunar polar regions are currently cold enough to cold-trap water ice as well as a range of both more volatile and less volatile species. The diverse mixture of water and high-volatility compounds detected in the LCROSS ejecta plume is strong evidence for the impact delivery and cold-trapping of volatiles derived from primitive outer solar system bodies.


Assuntos
Lua , Temperatura Baixa , Meio Ambiente Extraterreno , Gelo , Radiometria , Espectrofotometria Infravermelho
11.
Astrobiology ; 9(8): 745-58, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19845446

RESUMO

It has been widely understood for many years that an essential component of a Mars Sample Return mission is a Sample Receiving Facility (SRF). The purpose of such a facility would be to take delivery of the flight hardware that lands on Earth, open the spacecraft and extract the sample container and samples, and conduct an agreed-upon test protocol, while ensuring strict containment and contamination control of the samples while in the SRF. Any samples that are found to be non-hazardous (or are rendered non-hazardous by sterilization) would then be transferred to long-term curation. Although the general concept of an SRF is relatively straightforward, there has been considerable discussion about implementation planning. The Mars Exploration Program carried out an analysis of the attributes of an SRF to establish its scope, including minimum size and functionality, budgetary requirements (capital cost, operating costs, cost profile), and development schedule. The approach was to arrange for three independent design studies, each led by an architectural design firm, and compare the results. While there were many design elements in common identified by each study team, there were significant differences in the way human operators were to interact with the systems. In aggregate, the design studies provided insight into the attributes of a future SRF and the complex factors to consider for future programmatic planning.


Assuntos
Desenho de Equipamento , Meio Ambiente Extraterreno , Marte , Voo Espacial , Astronave , Contenção de Riscos Biológicos , Exobiologia , Humanos
12.
Astrobiology ; 8(6): 1093-1112, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19093802

RESUMO

Based on new image data from the High Resolution Imaging Science Experiment (HiRISE) on Mars Reconnaissance Orbiter (MRO), a case can be made that several structures in Vernal Crater, Arabia Terra are ancient springs. This interpretation is based on comprehensive geomorphologic analysis coupled with assessment of multiple hypotheses. The structures identified extend across several kilometers and are exceptional in that nothing with their detail and scale has been reported from Mars. The deposits are associated with an extensive fracture system that may have facilitated upward flow of warm fluids. Several additional spring-like features occur in Vernal Crater, and it is possible that these are part of a major province of spring activity. Since springs are environments where life could have evolved on Mars, where that life could have found refuge as the climate became colder and drier, and where signatures of that life may be preserved, Vernal Crater may be a site of major astrobiological importance.


Assuntos
Meio Ambiente Extraterreno , Fontes Termais , Marte , Voo Espacial , Austrália , História Antiga , Fatores de Tempo , Erupções Vulcânicas
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