22 research outputs found

    Decorrelation Stretches (DCS) of Visible Images as a Tool for Sedimentary Provenance Investigations on Earth and Mars

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    The surface of Mars exhibits vast expanses of mafic sediments and ancient sedimentary rocks that record signals of climate and environment. To decipher the paleoenvironments, the sediment sources and transport histories must be con-strained, but it is not well known how physical fractionation and aqueous alteration affect mafic sediments during glacial, eolian, and fluvial processes. Semi-Autonomous Navigation for Detrital Environments (SAND-E), a NASA Planetary Science and Technology through Analog Research (PSTAR) project, bridges this gap through studies of sediment-grain properties and mineralogy in the glacio-XRD)-derived mineralogies

    Overview and Initial Results of SAND-E: Semi-Autonomous Navigation for Detrital Environments

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    Unmanned aerial systems (UAS) and automated terrain analysis for science and navigation are new technologies for planetary exploration. The Mars Helicopter will fly with the Mars2020 rover, the Dragonfly quadcopter will explore Titan, and Soil Properties and Object Classification (SPOC) software will be used for path planning and navigation on the Mars2020 rover. Using an Argo J5 rover instrumented with stereo cameras and Autonomous Soil Assessment System (ASAS) software, and an off the shelf quadcopter, SAND-E tested the use of automated terrain analysis and UAS data for science operations in a Mars-analog environment in Iceland during July of 2019. Scientifically, we sought to determine changes in the physical and chemical properties of sediments along a glacial-fluvial-aeolian transport pathway. Operationally, we tested rover mission-like scenarios that included UAS images and classified terrain images. Here, we present the initial results for both the operations and science elements of the study. Site Selection: A goal of SAND-E is examine sorting and alteration of sediments in fluvial and aeolian environments in both mineral-dominated and glass-dominated basaltic settings. During the first year of the project we focused on a mineral-dominated environment. Selection of the location was based on prior publications that indicated our selected region had a greater abundance of crystalline sediments than other areas fluvial-aeolian settings in Iceland. Other criteria included the presence of both fluvial and aeolian landforms along a transport pathway such that the sediments in transport could be linked to their source rocks. We chose the Skjaldbreidauhraun glacial outwash plain, which sits at the base of Thrisjkull glacier. The site is 30 km north of Thingvellir National Park and ~2 hours from Reykjavik. The outwash plain is fed by two small catchments that drain from the base of the glacier and cut through hyaloclastite and shield volcano bedrock. The drainage progresses from steep alluvial fans near the glacier into a low-sloping fluvial braidplain that becomes confined by the Skjaldbreidur shield volcano and creates a shallow canyon cut into lava bedrock. The fluvial system was a typical braided alluvial environment composed pebble- and cobble-bedded longitudinal bars and sandy channel beds. The river remained active and fluctuated in response to diurnal runoff cycles near the glacier before disappearing into the sandy substrate downstream. The high concentration of suspended sediment in the river was evident by the cloudy water and the silt and clay-sized sediments that draped the channel beds after abandonment and created playas in the lowest sloping areas of the catchment. The entire fluvial system was affected by the winds generated by frontal systems and katabatic flows descending the glacier. This resulted in the formation of aeolian lag deposits and a wind-deflation plain where the fluvial system was not active. Wind ripples and drifts formed in abandoned fluvial channels from aeolian reworking of the sand-sized fluvial sediments. The silt- and clay-sized sediments found in fluvial channels, bar tops, and playas generated dust plumes during high wind events. Our operation sought to capture the variability in this system by sampling from the range of fluvial and aeolian features 6.3 km (proximal), 11.3 km (medial), and 14.4 km (distal) along the river from its origin at the base of glacier

    Artificial Intelligence for the Advancement of Lunar and Planetary Science and Exploration

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    AI-driven methods have potential to minimise manual labour during planetary data processing and aid ongoing missions with real-time data analysis. This white paper focuses on key areas of AI-driven research, the need for open source training data, and the importance of collaboration between academia and industries to advance AI-driven research

    A Parametric study and experimental testing of lunar-wheel suspension on dynamic terrainability

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    The development of a flexible metallic wheel proved to be one of the most challenging and time-consuming aspects of the Lunar Roving Vehicle of the Apollo missions (V. Asnani, D. Delap, and C. Creager. 2009. Journal of Terramechanics, 46: 89 103). The design was realized through an iterative trial and error design process, driven primarily by manufacturability and physical testing. Although the wire-mesh-compliant wheel design was identified as the best choice for the Lunar Roving Vehicle, mission scenarios have evolved and future lunar vehicles are bound to have to meet different functional requirements and more severe life and operational constraints..

    Validity of age estimation methods and reproducibility of bone/dental maturity indices for chronological age estimation: a systematic review and meta-analysis of validation studies

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    Several approaches have been developed to estimate age, an important aspect of forensics and orthodontics, using different measures and radiological examinations. Here, through meta-analysis, we determined the validity of age estimation methods and reproducibility of bone/dental maturity indices used for age estimation. The PubMed and Google Scholar databases were searched to December 31, 2021 for human cross-sectional studies meeting pre-defined PICOS criteria that simultaneously assessed the reproducibility and validity. Meta-estimates of validity (mean error: estimated age-chronological age) and intra- and inter-observer reproducibility (Cohen's kappa, intraclass correlation coefficient) and their predictive intervals (PI) were calculated using mixed-effect models when heterogeneity was high (I2 > 50%). The literature search identified 433 studies, and 23 met the inclusion criteria. The mean error meta-estimate (mixed effects model) was 0.08 years (95% CI - 0.12; 0.29) in males and 0.09 (95% CI - 0.12; 0.30) in females. The PI of each method spanned zero; of nine reported estimation methods, Cameriere's had the smallest (- 0.82; 0.47) and Haavikko's the largest (- 7.24; 4.57) PI. The reproducibility meta-estimate (fixed effects model) was 0.98 (95% CI 0.97; 1.00) for intra- and 0.99 (95% CI 0.98; 1.00) for inter-observer agreement. All methods were valid but with different levels of precision. The intra- and inter-observer reproducibility was high and homogeneous across studies

    Biomarkers of browning in cold exposed siberian adults

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    Cold-exposure promotes energy expenditure by inducing brown adipose tissue (BAT) thermogenesis, which over time, is also sustained by browning, the appearance, or increase, of brown-like cells into white fat depots. Identification of circulating markers reflecting BAT activity and browning is crucial to study this phenomenon and its triggers, also holding possible implications for the therapy of obesity and metabolic diseases. Using RT-qPCR, we evaluated the peripheral blood mononuclear cells (PBMC) expression profile of regulators of BAT activity (CIDEA, PRDM16), white adipocytes browning (HOXC9 and SLC27A1), and fatty acid \u3b2-oxidation (CPT1A) in 150 Siberian healthy miners living at extremely cold temperatures compared to 29 healthy subjects living in thermoneutral conditions. Anthropometric parameters, glucose, and lipid profiles were also assessed. The cold-exposed group showed significantly lower weight, BMI, hip circumference, and PBMC expression of CIDEA, but higher expression of HOXC9 and higher circulating glucose compared to controls. Within the cold-exposed group, BMI, total cholesterol, and the atherogenic coefficient were lower in individuals exposed to low temperatures for a longer time. In conclusion, human PBMC expresses the brown adipocytes marker CIDEA and the browning marker HOXC9, which, varying according to cold-exposure, possibly reflect changes in BAT activation and white fat browning

    Pachychoroid spectrum disease and choriocapillary flow analysis in patients with Cushing disease: an optical coherence tomography angiography study

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    Purpose: To investigate the presence of pachychoroid spectrum disease (PSD) in patients with Cushing disease (CD) and to evaluate subfoveal choroidal thickness (SFCT) and choriocapillary flow using spectral domain OCT (SD-OCT) with the enhanced depth imaging (EDI) and optical coherence tomography angiography (OCT-A). Methods: Thirty-two patients with CD and 32 age- and sex-matched healthy volunteers were enrolled in this observational study. All participants had a complete ophthalmic examination including SD-OCT with EDI and OCT-A, and were subjected to the Perceived Stress Scale test (PSS). All patients with CD had hormone test including 24-h urinary-free cortisol (UFC) and plasma adrenocorticotropic hormone (ACTH). We compared SFCT and choriocapillary vessel density (CVD) between the two groups and evaluated the presence of PSD. We investigated the association of hormone level, SFTC, CVD with the presence of CD; the association between the hormone level, SFTC, CVD, the CD disease activity, and duration with the presence of PSD in CD patients; and the association between SFTC and CVD with the hormone level, the CD disease activity, and duration in CD patients. Results: Higher values of SFCT and CVD were associated with CD (β: 0.028, 95% CI: 0.014; 0.041; β: 0.912, 95%CI: 0.205; 1.62, respectively). Twelve patients with CD (37.5%) reported a PSD in at least one eye, whereas no subject was found in control group (p < 0.001); in particular, 11 CD patients (34%) presented pachychoroid pigment epitheliopathy (PPE) and 1 CD patient (3%) presented polypoidal choroidal vasculopathy/aneurysmal type 1 neovascularization (PCV/AT1). In patients with CD, a significant positive association between SFCT and PSD was found (β: 0.010, 95% CI 0.001; 0.019). Conclusion: A chronic state of hypercortisolism may have direct implications on the choroid. Patients with CD had higher SFCT values and a significant change in the choriocapillary flow compared to healthy controls. Moreover, PSD was observed only in CD patients

    Occurrence of Idiopathic Pulmonary Fibrosis in Italy: Latest Evidence from Real-World Data

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    none10noThe aim of the study was to evaluate the trend in the incidence of idiopathic pulmonary fibrosis (IPF) in a real-world setting of the Marche region, a region of Central Italy, between 2014 and 2019. This observational prospective study was based on administrative databases of hospital discharges and drug prescriptions. All adult residents in the Marche Region with a first prescription of antifibrotic drugs, or a first hospitalization with a diagnosis of IPF during the study period, were identified as incident cases of IPF. A multiple Poisson regression analysis was used to estimate the IPF incidence trend, adjusted for age, sex, and health conditions. The mean incidence rate was 9.8 cases per 100,000 person-years. A significant increasing trend of 6% per year was observed. The incidence rates were significantly higher in males than females, older subjects, and those with poorer health conditions. To our knowledge, this is the first study evaluating incidences of IPF over a 6-year period in Italy, combining hospital discharge and drug prescription databases. The study highlights that the combined use of two secondary sources is a reliable strategy to accurately identify new cases of IPF when the appropriate disease registry is lacking.noneIommi M.; Bonifazi M.; Faragalli A.; Latini L.L.; Mei F.; Spazzafumo L.; Skrami E.; Ferrante L.; Carle F.; Gesuita R.Iommi, M.; Bonifazi, M.; Faragalli, A.; Latini, L. L.; Mei, F.; Spazzafumo, L.; Skrami, E.; Ferrante, L.; Carle, F.; Gesuita, R
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