188 results on '"Fraeman, A. A."'
Search Results
2. Gypsum on Mars: A Detailed View at Gale Crater
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David Vaniman, Steve Chipera, Elizabeth Rampe, Thomas Bristow, David Blake, Johannes Meusburger, Tanya Peretyazhko, William Rapin, Jeff Berger, Douglas Ming, Patricia Craig, Nicholas Castle, Robert T. Downs, Shaunna Morrison, Robert Hazen, Richard Morris, Aditi Pandey, Allan H. Treiman, Albert Yen, Cherie Achilles, Benjamin Tutolo, Elisabeth Hausrath, Sarah Simpson, Michael Thorpe, Valerie Tu, David J. Des Marais, John Grotzinger, and Abigail Fraeman
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Mars ,gypsum ,sulfate ,Mineralogy ,QE351-399.2 - Abstract
Gypsum is a common mineral at Gale crater on Mars, currently being explored by the Mars Science Laboratory (MSL) rover, Curiosity. In this paper, we summarize the associations of gypsum with other sulfate minerals (bassanite, anhydrite, jarosite, starkeyite, and kieserite) from the lowest levels of the crater’s northern moat zone (Aeolis Palus) up through ~0.8 km of the stratigraphic section in the lower slopes of the sedimentary mound developed around the central peak, Aeolis Mons (informally, Mount Sharp). The analysis is based on results from the CheMin X-ray diffraction instrument on Curiosity, supplemented with information from the rover’s versatile instrument suite. Gypsum does not occur with the same frequency as less hydrous Ca-sulfates, likely, in most cases, because of its dehydration to bassanite and possibly to anhydrite. All three of these Ca-sulfate phases often occur together and, along with other sulfates, in mixed assemblages that are evidence of limited equilibration on a cold, dry planet. In almost all samples, at least one of the Ca-sulfate minerals is present, except for a very limited interval where jarosite is the major sulfate mineral, with the implication of more acidic groundwater at a much later time in Gale crater’s history. Although observations from orbit reveal a sulfate-rich surface, currently active dark basaltic dunes at Gale crater have only small amounts of a single sulfate mineral, anhydrite. Gale crater has provided the most complete mineralogical analysis of a site on Mars so far, but the data in hand show that Gale crater mineralogy is not a blueprint with planet-wide application. The concurrent study of Jezero crater by the Mars 2020 mission and comparisons to what is believed to be the most extensive deposit of gypsum on Mars, in the dune fields at the north polar ice cap, show significant diversity. Unraveling the stories of gypsum and other sulfates on Mars is just beginning.
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- 2024
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3. Aeolian bedrock ridges in Gale crater, Mars
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Bretzfelder, Jordan M., Stack, Kathryn M., Fraeman, Abigail A., Day, Mackenzie, Dietrich, William E., and Bryk, Alexander B.
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- 2024
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4. Corrigendum: Real-World Treatment Patterns of Antiviral Prophylaxis for Cytomegalovirus Among Adult Kidney Transplant Recipients: A Linked USRDS-Medicare Database Study
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Amit D. Raval, Michael L. Ganz, Kathy Fraeman, Andrea L. Lorden, Shanmugapriya Saravanan, Yuexin Tang, and Carlos A. Q. Santos
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kidney transplantation ,antiviral ,cytomegalovirus ,prophylaxis ,pharmacoepidemiology ,Specialties of internal medicine ,RC581-951 - Abstract
Graphical Abstract
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- 2024
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5. The Chemistry and Mineralogy (CheMin) X-ray Diffractometer on the MSL Curiosity Rover: A Decade of Mineralogy from Gale Crater, Mars
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David Blake, Valerie Tu, Thomas Bristow, Elizabeth Rampe, David Vaniman, Steve Chipera, Philippe Sarrazin, Richard Morris, Shaunna Morrison, Albert Yen, Robert Downs, Robert Hazen, Allan Treiman, Douglas Ming, Gordon Downs, Cherie Achilles, Nicholas Castle, Tanya Peretyazhko, David De Marais, Patricia Craig, Barbara Lafuente, Benjamin Tutolo, Elisabeth Hausrath, Sarah Simpson, Richard Walroth, Michael Thorpe, Johannes Meusburger, Aditi Pandey, Marc Gailhanou, Przemyslaw Dera, Jeffrey Berger, Lucy Thompson, Ralf Gellert, Amy McAdam, Catherine O’Connell-Cooper, Brad Sutter, John Michael Morookian, Abigail Fraeman, John Grotzinger, Kirsten Siebach, Soren Madsen, and Ashwin Vasavada
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powder X-ray diffraction ,Mars ,extraterrestrial mineralogy ,Mars science laboratory ,Curiosity rover ,Mineralogy ,QE351-399.2 - Abstract
For more than a decade, the CheMin X-ray diffraction instrument on the Mars Science Laboratory rover, Curiosity, has been returning definitive and quantitative mineralogical and mineral–chemistry data from ~3.5-billion-year-old (Ga) sediments in Gale crater, Mars. To date, 40 drilled rock samples and three scooped soil samples have been analyzed during the rover’s 30+ km transit. These samples document the mineralogy of over 800 m of flat-lying fluvial, lacustrine, and aeolian sedimentary rocks that comprise the lower strata of the central mound of Gale crater (Aeolis Mons, informally known as Mt. Sharp) and the surrounding plains (Aeolis Palus, informally known as the Bradbury Rise). The principal mineralogy of the sedimentary rocks is of basaltic composition, with evidence of post-depositional diagenetic overprinting. The rocks in many cases preserve much of their primary mineralogy and sedimentary features, suggesting that they were never strongly heated or deformed. Using aeolian soil composition as a proxy for the composition of the deposited and lithified sediment, it appears that, in many cases, the diagenetic changes observed are principally isochemical. Exceptions to this trend include secondary nodules, calcium sulfate veining, and rare Si-rich alteration halos. A surprising and yet poorly understood observation is that nearly all of the ~3.5 Ga sedimentary rocks analyzed to date contain 15–70 wt.% of X-ray amorphous material. Overall, this >800 m section of sedimentary rock explored in lower Mt. Sharp documents a perennial shallow lake environment grading upward into alternating lacustrine/fluvial and aeolian environments, many of which would have been habitable to microbial life.
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- 2024
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6. Igneous Diversity of the Early Martian Crust
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Valerie Payré, Arya Udry, and Abigail A. Fraeman
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Mars ,crust ,petrology ,missions ,helicopter ,sub-alkaline ,Mineralogy ,QE351-399.2 - Abstract
Mars missions and Martian meteorites revealed how complex the Martian crust is. The occurrence of both alkaline and sub-alkaline igneous rocks of Noachian age (>3.7 Ga) in Gale crater indicates diverse magmatic processes, with sub-alkaline rocks likely formed through the partial melting of hydrous mafic rocks, as commonly observed on Earth. The orbital discovery of excavated evolved igneous rocks scattered in Noachian terrains raise questions about the petrology of the ancient Martian crust, long thought to be basaltic. A possibly evolved crust beneath a mafic cover is supported by geophysical and seismic measurements from the Insight lander that indicate the bulk crust has a lower density than expected if it were homogeneously basaltic. If localized magmatic processes could form evolved terrains, the detection of abundant intermediate to felsic Noachian crustal exposures through remote sensing suggest regional- to global-scale processes that produced evolved crustal component(s) that are now buried below mafic materials. Due to the lack of centimetric to millimetric textural imaging and compositional measurements, the petrology of such crust is ambiguous. Future orbiter, rover, and aerial missions should focus on Noachian exposed regions exhibiting evolved crustal characteristics to unfold the petrology of the Martian crust and its formation.
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- 2024
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7. Prebiotic reactions in a Mars analog iron mineral system: Effects of nitrate, nitrite, and ammonia on amino acid formation
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Barge, Laura M., Flores, Erika, Weber, Jessica M., Fraeman, Abigail A., Yung, Yuk L., VanderVelde, David, Martinez, Eduardo, Castonguay, Amalia, Billings, Keith, and Baum, Marc M.
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- 2022
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8. Fe/Mg-Silicate Chemical Gardens as Analogs to Silicate-Rich Hydrothermal Chimneys on Early Earth and Mars.
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Carman, Nancy A., Hausrath, Elisabeth M., Celestian, Aaron, Chavez, Julia, Hermis, Ninos, LaRowe, Douglas E., Fraeman, Abigail A., Sheppard, Rachel Y., Adcock, Christopher T., Tschauner, Oliver, Rampe, Elizabeth B., Price, Roy, and Barge, Laura M.
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- 2024
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9. Individualized HbA1c target selection and achievement in the Multinational Observational Study Assessing Insulin Use (MOSA1c) type 2 diabetes study
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Caballero, A. Enrique, Nordstrom, Beth L., Liao, Birong, Fan, Ludi, Zhang, Nan, Fraeman, Kathy H., and Perez-Nieves, Magaly
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- 2021
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10. Risk of venous thromboembolism among women receiving ospemifene: a comparative observational study
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Beth L. Nordstrom, Bin Cai, Fabio De Gregorio, Lu Ban, Kathy H. Fraeman, Yuki Yoshida, and Trevor Gibbs
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Therapeutics. Pharmacology ,RM1-950 - Abstract
Introduction: The primary aim of this study was to compare the incidence of venous thromboembolism (VTE) among women initiating ospemifene vs other selective estrogen receptor modulator (SERM) therapies for estrogen-deficiency conditions or breast cancer prevention, and vs women with untreated vulvar and vaginal atrophy (VVA). The secondary objective examined numerous additional safety outcomes. Methods: This was a retrospective cohort study using the IBM Watson MarketScan claims database. Women receiving ospemifene, another SERM, or with a new diagnosis of VVA with no treatment from 1 May 2013 to 2 October 2018 were followed through the claims for incident adverse outcomes. The primary outcome was the first occurrence of VTE following cohort entry; secondary outcomes included cerebrovascular events and other adverse events potentially associated with SERM use. Cox models compared the risk of VTE between ospemifene and comparators, using a variety of approaches to control for confounding. Results: The incidence of VTE during the first continuous treatment episode was 3.39 (95% confidence interval [CI]: 1.55–6.43) events per 1,000 person-years (PY) for ospemifene ( N = 8977), 11.30 (95% CI: 8.81–14.28) events per 1,000 PY for comparator SERM ( N = 12,621), and 10.92 (95% CI: 10.49–11.37) events per 1,000 PY for untreated VVA ( N = 242,488). Cox models indicated no increase in risk of VTE for ospemifene vs other SERMs (hazard ratio [HR]: 0.40, 95% CI: 0.19–0.82), and vs untreated VVA (HR: 0.47, 95% CI: 0.24–0.91). Conclusion: This real-world safety analysis found no increase in risk of VTE or other adverse events with use of ospemifene in postmenopausal women. Plain Language Summary Introduction: This study assessed the risk of venous thromboembolism (VTE) among women treated with ospemifene or another selective estrogen receptor modulator (SERM) therapy and women with untreated vulvar and vaginal atrophy (VVA). Numerous additional safety outcomes were examined. Methods: This study was conducted in the IBM Watson MarketScan claims database. Women receiving ospemifene, another SERM, or with a new diagnosis of VVA with no treatment from 1 May 2013 to 2 October 2018 were followed through the claims for adverse outcomes, including VTE, cerebrovascular events (such as stroke), and other outcomes that might occur with use of a SERM. The analyses compared the risk of VTE between ospemifene and the other two groups, using methods that accounted for differences in patient characteristics between the groups. Because few women over 72 years old used ospemifene, the main analyses examined women aged 54–72 years. Results: The analyses included 8,977 ospemifene users, 12,621 other SERM users, and 242,488 women with untreated VVA. Among women aged 54–72 years, only 9 experienced a VTE during ospemifene treatment, while 55 other SERM users and 1,788 women with untreated VVA had a VTE. The analyses that accounted for differences between the groups confirmed that the risk of VTE was no higher in ospemifene users than in either comparison group. Conclusion: This real-world safety analysis found no increase in risk of VTE or other adverse events with use of ospemifene in postmenopausal women.
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- 2022
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11. Real-World Treatment Patterns of Antiviral Prophylaxis for Cytomegalovirus Among Adult Kidney Transplant Recipients: A Linked USRDS-Medicare Database Study
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Amit D. Raval, Michael L. Ganz, Kathy Fraeman, Andrea L. Lorden, Shanmugapriya Saravanan, Yuexin Tang, and Carlos A. Q. Santos
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kidney transplantation ,antiviral ,cytomegalovirus ,prophylaxis ,pharmacoepidemiology ,Specialties of internal medicine ,RC581-951 - Abstract
Limited data exist on cytomegalovirus (CMV) antiviral treatment patterns among kidney transplant recipients (KTRs). Using United States Renal Database System registry data and Medicare claims (1 January 2011–31 December 2017), we examined CMV antiviral use in 20,601 KTRs who received their first KT from 2011 to 2016. Three-quarters of KTRs started CMV prophylaxis (86.9% of high-, 83.6% of intermediate-, and 31.7% of low-risk KTRs). Median time to prophylaxis discontinuation was 121, 90, and 90 days for high-, intermediate-, and low-risk KTRs, respectively. Factors associated with receiving CMV prophylaxis were high-risk status, diabetes, receipt of a well-functioning kidney graft, greater time on dialysis before KT, panel reactive antibodies ≥80%, and use of antithymocyte globulin, alemtuzumab, and tacrolimus. KTRs were more likely to discontinue CMV prophylaxis if they developed leukopenia/neutropenia, had liver disease, or had a deceased donor. These findings suggest that adherence to the recommended duration of CMV-prophylaxis for high and intermediate-risk patients is suboptimal, and CMV prophylaxis is overused in low-risk patients.
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- 2022
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12. The sustainability of habitability on terrestrial planets: Insights, questions, and needed measurements from Mars for understanding the evolution of Earth‐like worlds
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Ehlmann, BL, Anderson, FS, Andrews‐Hanna, J, Catling, DC, Christensen, PR, Cohen, BA, Dressing, CD, Edwards, CS, Elkins‐Tanton, LT, Farley, KA, Fassett, CI, Fischer, WW, Fraeman, AA, Golombek, MP, Hamilton, VE, Hayes, AG, Herd, CDK, Horgan, B, Hu, R, Jakosky, BM, Johnson, JR, Kasting, JF, Kerber, L, Kinch, KM, Kite, ES, Knutson, HA, Lunine, JI, Mahaffy, PR, Mangold, N, McCubbin, FM, Mustard, JF, Niles, PB, Quantin‐Nataf, C, Rice, MS, Stack, KM, Stevenson, DJ, Stewart, ST, Toplis, MJ, Usui, T, Weiss, BP, Werner, SC, Wordsworth, RD, Wray, JJ, Yingst, RA, Yung, YL, and Zahnle, KJ
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Climate Action ,Mars history ,planetary evolution ,habitability ,sustainability ,terrestrial exoplanets ,Astronomical and Space Sciences ,Geochemistry ,Geology - Abstract
What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar system's longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to understanding the factors driving the divergent evolutionary paths of the Earth, Venus, and thousands of small rocky extrasolar planets yet to be discovered.
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- 2016
13. Exploring Martian Magnetic Fields with a Helicopter
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Anna Mittelholz, Lindsey Heagy, Catherine L. Johnson, Jonathan Bapst, Jared Espley, Abigail A. Fraeman, Benoit Langlais, Robert Lillis, and William Rapin
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Mars ,Solar system terrestrial planets ,Planetary magnetospheres ,Planetary science ,Planetary interior ,Planetary structure ,Astronomy ,QB1-991 - Abstract
The era of helicopter-based surveys on Mars has already begun, creating opportunities for future aerial science investigations with a range of instruments. We argue that magnetometer-based studies can make use of aerial technology to answer some of the key questions regarding early Mars evolution. As such, we discuss mission concepts for a helicopter equipped with a magnetometer on Mars, measurements it would provide, and survey designs that could be implemented. For a range of scenarios, we build magnetization models and test how well structures can be resolved using a range of different inversion approaches. With this work, we provide modeling ground work and recommendations to plan the future of aerial Mars exploration.
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- 2023
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14. A Habitable Fluvio-Lacustrine Environment at Yellowknife Bay, Gale Crater, Mars
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Grotzinger, JP, Sumner, DY, Kah, LC, Stack, K, Gupta, S, Edgar, L, Rubin, D, Lewis, K, Schieber, J, Mangold, N, Milliken, R, Conrad, PG, DesMarais, D, Farmer, J, Siebach, K, Calef, F, Hurowitz, J, McLennan, SM, Ming, D, Vaniman, D, Crisp, J, Vasavada, A, Edgett, KS, Malin, M, Blake, D, Gellert, R, Mahaffy, P, Wiens, RC, Maurice, S, Grant, JA, Wilson, S, Anderson, RC, Beegle, L, Arvidson, R, Hallet, B, Sletten, RS, Rice, M, Bell, J, Griffes, J, Ehlmann, B, Anderson, RB, Bristow, TF, Dietrich, WE, Dromart, G, Eigenbrode, J, Fraeman, A, Hardgrove, C, Herkenhoff, K, Jandura, L, Kocurek, G, Lee, S, Leshin, LA, Leveille, R, Limonadi, D, Maki, J, McCloskey, S, Meyer, M, Minitti, M, Newsom, H, Oehler, D, Okon, A, Palucis, M, Parker, T, Rowland, S, Schmidt, M, Squyres, S, Steele, A, Stolper, E, Summons, R, Treiman, A, Williams, R, Yingst, A, Team, MSL Science, Kemppinen, Osku, Bridges, Nathan, Johnson, Jeffrey R, Cremers, David, Godber, Austin, Wadhwa, Meenakshi, Wellington, Danika, McEwan, Ian, Newman, Claire, Richardson, Mark, Charpentier, Antoine, Peret, Laurent, King, Penelope, Blank, Jennifer, Weigle, Gerald, Li, Shuai, Robertson, Kevin, Sun, Vivian, Baker, Michael, Edwards, Christopher, Farley, Kenneth, Miller, Hayden, Newcombe, Megan, Pilorget, Cedric, Brunet, Claude, Hipkin, Victoria, and Léveillé, Richard
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Bays ,Carbon ,Exobiology ,Extraterrestrial Environment ,Geologic Sediments ,Hydrogen ,Hydrogen-Ion Concentration ,Iron ,Mars ,Nitrogen ,Oxidation-Reduction ,Oxygen ,Phosphorus ,Salinity ,Sulfur ,Water ,MSL Science Team ,General Science & Technology - Abstract
The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of an environment that would have been suited to support a martian biosphere founded on chemolithoautotrophy. This aqueous environment was characterized by neutral pH, low salinity, and variable redox states of both iron and sulfur species. Carbon, hydrogen, oxygen, sulfur, nitrogen, and phosphorus were measured directly as key biogenic elements; by inference, phosphorus is assumed to have been available. The environment probably had a minimum duration of hundreds to tens of thousands of years. These results highlight the biological viability of fluvial-lacustrine environments in the post-Noachian history of Mars.
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- 2014
15. Development and validation of algorithms for identifying lines of therapy in multiple myeloma using real-world data.
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Ailawadhi, Sikander, Romanus, Dorothy, Shah, Surbhi, Fraeman, Kathy, Saragoussi, Delphine, Buus, Rebecca Morris, Nguyen, Binh, Cherepanov, Dasha, Lamerato, Lois, and Berger, Ariel
- Abstract
Aim: To validate algorithms based on electronic health data to identify composition of lines of therapy (LOT) in multiple myeloma (MM). Materials & methods: This study used available electronic health data for selected adults within Henry Ford Health (Michigan, USA) newly diagnosed with MM in 2006–2017. Algorithm performance in this population was verified via chart review. As with prior oncology studies, good performance was defined as positive predictive value (PPV) ≥75%. Results: Accuracy for identifying LOT1 (N = 133) was 85.0%. For the most frequent regimens, accuracy was 92.5–97.7%, PPV 80.6–93.8%, sensitivity 88.2–89.3% and specificity 94.3–99.1%. Algorithm performance decreased in subsequent LOTs, with decreasing sample sizes. Only 19.5% of patients received maintenance therapy during LOT1. Accuracy for identifying maintenance therapy was 85.7%; PPV for the most common maintenance therapy was 73.3%. Conclusion: Algorithms performed well in identifying LOT1 – especially more commonly used regimens – and slightly less well in identifying maintenance therapy therein. Electronic health data helps us understand treatment in the 'real world'. The data has great value in cancer if we can identify the drugs patients get. Yet this is hard in multiple myeloma (MM), where treatment is complex. Algorithms (set of decision rules) to identify drugs can help here. We tested an existing algorithm for identifying 'lines of therapy' (LOT) given to patients with MM. Each LOT included one or more drugs for MM. We also developed and tested a new algorithm for 'maintenance therapy'. This is a treatment given to help maintain the response to the main MM treatment. We tested how well the algorithms identified MM treatments in electronic health data. This data came from Henry Ford Health, a healthcare system in Michigan, USA. Treatments were confirmed by cancer specialists who reviewed medical charts. The LOT algorithm was good at finding the first LOT patients. The maintenance algorithm did a fair job of identifying the most used therapy. Our algorithms could help researchers study the real-world treatment of MM. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Igneous Diversity of the Early Martian Crust.
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Payré, Valerie, Udry, Arya, and Fraeman, Abigail A.
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MARTIAN meteorites ,ALKALIC igneous rocks ,GALE Crater (Mars) ,MAFIC rocks ,GEOLOGICAL time scales ,IGNEOUS rocks ,METEORITES - Abstract
Mars missions and Martian meteorites revealed how complex the Martian crust is. The occurrence of both alkaline and sub-alkaline igneous rocks of Noachian age (>3.7 Ga) in Gale crater indicates diverse magmatic processes, with sub-alkaline rocks likely formed through the partial melting of hydrous mafic rocks, as commonly observed on Earth. The orbital discovery of excavated evolved igneous rocks scattered in Noachian terrains raise questions about the petrology of the ancient Martian crust, long thought to be basaltic. A possibly evolved crust beneath a mafic cover is supported by geophysical and seismic measurements from the Insight lander that indicate the bulk crust has a lower density than expected if it were homogeneously basaltic. If localized magmatic processes could form evolved terrains, the detection of abundant intermediate to felsic Noachian crustal exposures through remote sensing suggest regional- to global-scale processes that produced evolved crustal component(s) that are now buried below mafic materials. Due to the lack of centimetric to millimetric textural imaging and compositional measurements, the petrology of such crust is ambiguous. Future orbiter, rover, and aerial missions should focus on Noachian exposed regions exhibiting evolved crustal characteristics to unfold the petrology of the Martian crust and its formation. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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17. STK11 (LKB1) mutations in metastatic NSCLC: Prognostic value in the real world.
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Norah J Shire, Alyssa B Klein, Asieh Golozar, Jenna M Collins, Kathy H Fraeman, Beth L Nordstrom, Robert McEwen, Todd Hembrough, and Naiyer A Rizvi
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Medicine ,Science - Abstract
BackgroundMutations in STK11 (STK11m) and frequently co-occurring KRAS mutations (KRASm/STK11m) are associated with poor survival in metastatic NSCLC (mNSCLC) immuno-oncology trials. There are limited data regarding the prognostic significance of these mutations in a real-world setting.MethodsThis retrospective cohort study analyzed de-identified electronic medical records from the Flatiron Clinico-Genomic database to identify patients with mNSCLC who had initiated first-line immunotherapy (IO; alone or in combination) or chemotherapy under routine care between January 1, 2013 and June 30, 2017. The primary objectives were to assess the prevalence of STK11m and KRASm/STK11m and to determine associations of these mutations with overall and progression-free survival (OS, PFS).ResultsOf 2407 patients with mNSCLC, STK11m and KRASm/STK11m were present in 13.6% and 6.5% of patients, respectively. Worse OS outcomes were observed in patients with STK11m versus STK11wt mNSCLC receiving IO (first-line, HR [95% CI], 1.4 [0.9-2.3; p = 0.1]; second-line [subset of first-line cohort], HR, 1.6 [1.3-2.0; p = 0.0002]) or chemotherapy (first-line, HR, 1.4 [1.2-1.6; p < 0.0001]); PFS outcomes showed similar trends. KRASm/STK11m double mutations were associated with worse OS and PFS outcomes versus KRASwt/STK11wt with IO and chemotherapy, similar to the single mutation (STK11m vs STK11wt) findings.ConclusionsThis large observational genomic study among patients receiving routine care highlights the negative prognostic impact of STK11m in patients with mNSCLC treated with IO or chemotherapy. These results complement previous clinical trial data and provide further evidence in the real world of a patient population that would benefit from new treatment options.
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- 2020
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18. Relating geologic units and mobility system kinematics contributing to Curiosity wheel damage at Gale Crater, Mars
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Arvidson, R.E., DeGrosse, P., Jr, Grotzinger, J.P., Heverly, M.C., Shechet, J., Moreland, S.J., Newby, M.A., Stein, N., Steffy, A.C., Zhou, F., Zastrow, A.M., Vasavada, A.R., Fraeman, A.A., and Stilly, E.K.
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- 2017
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19. Real-World Treatment Patterns of Antiviral Prophylaxis for Cytomegalovirus Among Adult Kidney Transplant Recipients: A Linked USRDS-Medicare Database Study.
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Raval, Amit D., Ganz, Michael L., Fraeman, Kathy, Lorden, Andrea L., Saravanan, Shanmugapriya, Yuexin Tang, and Santos, Carlos A. Q.
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KIDNEY transplantation ,ALEMTUZUMAB ,DATABASES ,CYTOMEGALOVIRUSES ,PREVENTIVE medicine ,ADULTS ,DEAD ,INTERNET content management systems - Abstract
Limited data exist on cytomegalovirus (CMV) antiviral treatment patterns among kidney transplant recipients (KTRs). Using United States Renal Database System registry data and Medicare claims (1 January 2011-31 December 2017), we examined CMV antiviral use in 20,601 KTRs who received their first KT from 2011 to 2016. Three-quarters of KTRs started CMV prophylaxis (86.9% of high-, 83.6% of intermediate-, and 31.7% of low-risk KTRs). Median time to prophylaxis discontinuation was 121, 90, and 90 days for high-, intermediate-, and low-risk KTRs, respectively. Factors associated with receiving CMV prophylaxis were highrisk status, diabetes, receipt of a well-functioning kidney graft, greater time on dialysis before KT, panel reactive antibodies =80%, and use of antithymocyte globulin, alemtuzumab, and tacrolimus. KTRs were more likely to discontinue CMV prophylaxis if they developed leukopenia/neutropenia, had liver disease, or had a deceased donor. These findings suggest that adherence to the recommended duration of CMV-prophylaxis for high and intermediate-risk patients is suboptimal, and CMV prophylaxis is overused in low-risk patients. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Merging Perspectives on Secondary Minerals on Mars: A Review of Ancient Water-Rock Interactions in Gale Crater Inferred from Orbital and In-Situ Observations
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Rachel Y. Sheppard, Michael T. Thorpe, Abigail A. Fraeman, Valerie K. Fox, and Ralph E. Milliken
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Mars ,secondary mineralogy ,Gale crater ,phyllosilicates ,sulfates ,diagenesis ,Mineralogy ,QE351-399.2 - Abstract
Phyllosilicates, sulfates, and Fe oxides are the most prevalent secondary minerals detected on Mars from orbit and the surface, including in the Mars Science Laboratory Curiosity rover’s field site at Gale crater. These records of aqueous activity have been investigated in detail in Gale crater, where Curiosity’s X-ray diffractometer allows for direct observation and detailed characterization of mineral structure and abundance. This capability provides critical ground truthing to better understand how to interpret Martian mineralogy inferred from orbital datasets. Curiosity is about to leave behind phyllosilicate-rich strata for more sulfate-rich terrains, while the Mars 2020 Perseverance rover is in its early exploration of ancient sedimentary strata in Jezero crater. It is thus an appropriate time to review Gale crater’s mineral distribution from multiple perspectives, utilizing the range of chemical, mineralogical, and spectral measurements provided by orbital and in situ observations. This review compares orbital predictions of composition in Gale crater with higher fidelity (but more spatially restricted) in situ measurements by Curiosity, and we synthesize how this information contributes to our understanding of water-rock interaction in Gale crater. In the context of combining these disparate spatial scales, we also discuss implications for the larger understanding of martian surface evolution and the need for a wide range of data types and scales to properly reconstruct ancient geologic processes using remote methods.
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- 2021
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21. Incidence of venous thromboembolism among postmenopausal women prescribed ospemifene, selective estrogen receptor modulators for noncancer indications, or untreated vulvar and vaginal atrophy
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Nordstrom, Beth L., Cai, Bin, De Gregorio, Fabio, Dhalwani, Nafeesa, Fraeman, Kathy H., Yoshida, Yuki, and Gibbs, Trevor
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- 2020
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22. Comparing orbiter and rover image-based mapping of an ancient sedimentary environment, Aeolis Palus, Gale crater, Mars
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Stack, K.M., Edwards, C.S., Grotzinger, J.P., Gupta, S., Sumner, D.Y., Calef, F.J., III, Edgar, L.A., Edgett, K.S., Fraeman, A.A., Jacob, S.R., Le Deit, L., Lewis, K.W., Rice, M.S., Rubin, D., Williams, R.M.E., and Williford, K.H.
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- 2016
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23. A Review of the Phyllosilicates in Gale Crater as Detected by the CheMin Instrument on the Mars Science Laboratory, Curiosity Rover
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Valerie M. Tu, Elizabeth B. Rampe, Thomas F. Bristow, Michael T. Thorpe, Joanna V. Clark, Nicholas Castle, Abigail A. Fraeman, Lauren A. Edgar, Amy McAdam, Candice Bedford, Cherie N. Achilles, David Blake, Steve J. Chipera, Patricia I. Craig, David J. Des Marais, Gordon W. Downs, Robert T. Downs, Valerie Fox, John P. Grotzinger, Robert M. Hazen, Douglas W. Ming, Richard V. Morris, Shaunna M. Morrison, Betina Pavri, Jennifer Eigenbrode, Tanya S. Peretyazhko, Philippe C. Sarrazin, Brad Sutter, Allan H. Treiman, David T. Vaniman, Ashwin R. Vasavada, Albert S. Yen, and John C. Bridges
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clay minerals ,phyllosilicates ,organic preservation ,Mars ,gale crater ,X-ray diffraction ,Mineralogy ,QE351-399.2 - Abstract
Curiosity, the Mars Science Laboratory (MSL) rover, landed on Mars in August 2012 to investigate the ~3.5-billion-year-old (Ga) fluvio-lacustrine sedimentary deposits of Aeolis Mons (informally known as Mount Sharp) and the surrounding plains (Aeolis Palus) in Gale crater. After nearly nine years, Curiosity has traversed over 25 km, and the Chemistry and Mineralogy (CheMin) X-ray diffraction instrument on-board Curiosity has analyzed 30 drilled rock and three scooped soil samples to date. The principal strategic goal of the mission is to assess the habitability of Mars in its ancient past. Phyllosilicates are common in ancient Martian terrains dating to ~3.5–4 Ga and were detected from orbit in some of the lower strata of Mount Sharp. Phyllosilicates on Earth are important for harboring and preserving organics. On Mars, phyllosilicates are significant for exploration as they are hypothesized to be a marker for potential habitable environments. CheMin data demonstrate that ancient fluvio-lacustrine rocks in Gale crater contain up to ~35 wt. % phyllosilicates. Phyllosilicates are key indicators of past fluid–rock interactions, and variation in the structure and composition of phyllosilicates in Gale crater suggest changes in past aqueous environments that may have been habitable to microbial life with a variety of possible energy sources.
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- 2021
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24. Large wind ripples on Mars: A record of atmospheric evolution
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Lapotre, M. G. A., Ewing, R. C., Lamb, M. P., Fischer, W. W., Grotzinger, J. P., Rubin, D. M., Lewis, K. W., Ballard, M. J., Day, M., Gupta, S., Banham, S. G., Bridges, N. T., Des Marais, D. J., Fraeman, A. A., Grant, J. A., Herkenhoff, K. E., Ming, D. W., Mischna, M. A., Rice, M. S., Sumner, D. A., Vasavada, A. R., and Yingst, R. A.
- Published
- 2016
25. Prescriber Compliance With Liver Monitoring Guidelines for Pazopanib in the Postapproval Setting: Results From a Distributed Research Network
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Shantakumar, Sumitra, Nordstrom, Beth L., Hall, Susan A., Djousse, Luc, van Herk-Sukel, Myrthe P.P., Fraeman, Kathy H., Gagnon, David R., Chagin, Karen, and Nelson, Jeanenne J.
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- 2019
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26. Mineralogical Investigation of Mg‐Sulfate at the Canaima Drill Site, Gale Crater, Mars.
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Chipera, S. J., Vaniman, D. T., Rampe, E. B., Bristow, T. F., Martínez, G., Tu, V. M., Peretyazhko, T. S., Yen, A. S., Gellert, R., Berger, J. A., Rapin, W., Morris, R. V., Ming, D. W., Thompson, L. M., Simpson, S., Achilles, C. N., Tutolo, B., Downs, R. T., Fraeman, A. A., and Fischer, E.
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GALE Crater (Mars) ,MARTIAN surface ,MARS (Planet) ,MARS rovers ,SULFATE minerals ,MAGNESIUM - Abstract
For the first time on Mars, the crystalline magnesium‐sulfate mineral starkeyite (MgSO4‧4H2O) was definitively identified using the CheMin X‐ray diffraction instrument at Gale crater. At the Canaima drill site, starkeyite along with amorphous MgSO4‧nH2O are among the "polyhydrated Mg‐sulfates" interpreted in orbital reflectance spectra. Mg‐sulfates are good climate indicators as they are very responsive to changes in temperature and relative humidity. We hypothesize that, through evaporation, Mg‐sulfates formed at the end of brine evolution when ion concentrations became saturated and precipitated on the surface or near sub‐surface as either epsomite or meridianiite. These minerals were subsequently dehydrated later to starkeyite and amorphous MgSO4‧nH2O in response to a drier Mars. At Canaima, starkeyite is stable and would form during the warmer Mars summers. Due to very slow kinetics at the low Mars winter temperatures, starkeyite and amorphous MgSO4‧nH2O would be resistant to recrystallize to more hydrous forms and thus likely persist year‐round. During the course of analyses, starkeyite transforms into amorphous MgSO4‧nH2O inside the rover body due to the elevated temperature and greatly reduced relative humidity compared to the martian surface at the Canaima drill site. It is possible that crystalline sulfate minerals existed in earlier samples measured by CheMin but altered inside the rover before they could be analyzed. Starkeyite is most likely prevalent in the subsurface, whereas both starkeyite and amorphous MgSO4‧nH2O are likely present on the surface as starkeyite could partially transform into amorphous MgSO4‧nH2O due to direct solar heating. Plain Language Summary: For the first time on Mars, starkeyite (MgSO4‧4H2O), one of the many possible naturally occurring Mg‐sulfate minerals, has been identified using instruments that determine the mineralogy and chemistry of samples on the Curiosity rover in Gale crater. Minerals form in response to conditions they are subjected to and can be used to infer temperature, pressure, water availability, and other factors that will influence their formation. As such, their presence can be used to help define current and past climate conditions on Mars. When Mg‐sulfate minerals first precipitate from brine that is evaporating on the surface, they form more hydrous varieties. In response to drier conditions, they will recrystallize to Mg‐sulfate forms with less water in them. When Mg‐sulfate minerals are desiccated under extremely dry conditions, they will lose their crystal structure and form an amorphous phase. This occurred inside the rover body during the analysis of the Canaima sample. It is likely that earlier samples may also have contained crystalline Mg‐sulfates but altered to an amorphous phase while in the rover body before analyses could take place. Mg‐sulfate in the subsurface is likely starkeyite but could partially transform on the surface to amorphous MgSO4‧nH2O due to direct solar heating. Key Points: For the first time on Mars, starkeyite (MgSO4‧4H2O) was positively identifiedStarkeyite along with amorphous MgSO4‧nH2O are the "polyhydrated Mg‐sulfates" interpreted in orbital reflectance spectraMg‐sulfate mineralogy serves as an indicator of transition to a drier climate and helps outline the climatic and depositional changes on Mars [ABSTRACT FROM AUTHOR]
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- 2023
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27. Mortality and comorbidities in patients with multiple sclerosis compared with a population without multiple sclerosis: An observational study using the US Department of Defense administrative claims database
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Capkun, Gorana, Dahlke, Frank, Lahoz, Raquel, Nordstrom, Beth, Tilson, Hugh H, Cutter, Gary, Bischof, Dorina, Moore, Alan, Simeone, Jason, Fraeman, Kathy, Bancken, Fabrice, Geissbühler, Yvonne, Wagner, Michael, and Cohan, Stanley
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- 2015
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28. 238P Real-world treatment (Tx) patterns in patients (pts) with HR+/HER2– metastatic breast cancer (mBC) treated with chemotherapy (CT) in the United States (US)
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Punie, K., Jhaveri, K., Tolaney, S.M., Ntalla, I., Shah, A., Sjekloca, N., Fraeman, K., and Carey, L.A.
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- 2023
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29. Spectral absorptions on Phobos and Deimos in the visible/near infrared wavelengths and their compositional constraints
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Fraeman, A.A., Murchie, S.L., Arvidson, R.E., Clark, R.N., Morris, R.V., Rivkin, A.S., and Vilas, F.
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- 2014
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30. A Habitable Fluvio-Lacustrine Environment at Yellowknife Bay, Gale Crater, Mars
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MSL Science Team, Grotzinger, J. P., Sumner, D. Y., Kah, L. C., Stack, K., Gupta, S., Edgar, L., Rubin, D., Lewis, K., Schieber, J., Mangold, N., Milliken, R., Conrad, P. G., DesMarais, D., Farmer, J., Siebach, K., Calef, F., Hurowitz, J., McLennan, S. M., Ming, D., Vaniman, D., Crisp, J., Vasavada, A., Edgett, K. S., Malin, M., Blake, D., Gellert, R., Mahaffy, P., Wiens, R. C., Maurice, S., Grant, J. A., Wilson, S., Anderson, R. C., Beegle, L., Arvidson, R., Hallet, B., Sletten, R. S., Rice, M., Bell, J., Griffes, J., Ehlmann, B., Anderson, R. B., Bristow, T. F., Dietrich, W. E., Dromart, G., Eigenbrode, J., Fraeman, A., Hardgrove, C., Herkenhoff, K., Jandura, L., Kocurek, G., Lee, S., Leshin, L. A., Leveille, R., Limonadi, D., Maki, J., McCloskey, S., Meyer, M., Minitti, M., Newsom, H., Oehler, D., Okon, A., Palucis, M., Parker, T., Rowland, S., Schmidt, M., Squyres, S., Steele, A., Stolper, E., Summons, R., Treiman, A., Williams, R., and Yingst, A.
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- 2014
31. Occurrence of hepatotoxicity with pazopanib and other anti-VEGF treatments for renal cell carcinoma: an observational study utilizing a distributed database network
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Shantakumar, Sumitra, Nordstrom, Beth L., Djousse, Luc, Hall, Susan A., Gagnon, David R., Fraeman, Kathy H., van Herk-Sukel, Myrthe, Chagin, Karen, and Nelson, Jeanenne
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- 2016
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32. Mission to the Trojan asteroids: Lessons learned during a JPL Planetary Science Summer School mission design exercise
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Diniega, Serina, Sayanagi, Kunio M., Balcerski, Jeffrey, Carande, Bryce, Diaz-Silva, Ricardo A., Fraeman, Abigail A., Guzewich, Scott D., Hudson, Jennifer, Nahm, Amanda L., Potter-McIntyre, Sally, Route, Matthew, Urban, Kevin D., Vasisht, Soumya, Benneke, Bjoern, Gil, Stephanie, Livi, Roberto, Williams, Brian, Budney, Charles J., and Lowes, Leslie L.
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- 2013
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33. Compositional Variations in Sedimentary Deposits in Gale Crater as Observed by ChemCam Passive and Active Spectra.
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Manelski, H. T., Sheppard, R. Y., Fraeman, A. A., Wiens, R. C., Johnson, J. R., Rampe, E. B., Frydenvang, J., Lanza, N. L., and Gasnault, O.
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GALE Crater (Mars) ,LASER-induced breakdown spectroscopy ,SCIENTIFIC apparatus & instruments ,MARS rovers ,BEDROCK ,INFRARED cameras ,FERRIC oxide ,IRON ,CAMERAS - Abstract
During the first 2934 sols of the Curiosity rover's mission 33,468 passive visible/near‐infrared (NIR) reflectance spectra were taken of the surface by the mast‐mounted Chemistry and Camera (ChemCam) instrument on a range of target types. ChemCam spectra of bedrock targets from the Murray and Carolyn Shoemaker formations on Mt. Sharp were investigated using principal component analysis and various spectral parameters including the band depth at 535 nm and the slope between 840 and 750 nm. Four end‐member spectra were identified. Passive spectra were compared to Laser Induced Breakdown Spectroscopy (LIBS) data to search for correlations between spectral properties and elemental abundances. The correlation coefficient between FeOT reported by LIBS and BD535 from passive spectra was used to search for regions where iron may have been added to the bedrock through oxidation of ferrous‐bearing fluids but no correlations were found. Rocks in the Blunts Point‐Sutton Island transition that have unique spectral properties compared to surrounding rocks, that is flat NIR slopes and weak 535 nm absorptions, are associated with higher Mn and Mg in the LIBS spectra of bedrock. Additionally, calcium‐sulfate cements, previously identified by Ca and S enrichments in the LIBS spectra of bedrock, were also shown to be associated with spectral trends seen in Blunts Point. A shift toward a steeper NIR slope is seen in the Hutton interval, indicative of changing depositional conditions or increased diagenesis. Plain Language Summary: The Chemistry and Camera (ChemCam) instrument on the Mars Science Laboratory Curiosity rover was built for use in "active" mode, in which a laser vaporizes a small amount of material from a targets' surface and the light emitted from the resulting plasma is used to quantify the relative amounts of various elements. ChemCam also collects "passive" spectra (without the use of the laser). These passive spectra use reflected sunlight to provide complementary mineralogical information. By looking at how passive and active spectral features relate and change, we can further our understanding of the composition of targets that the rover has encountered. Specifically, this methodology can help determine if Curiosity encountered rocks altered by fluids containing reduced iron. Comparison between passive spectral parameters and iron oxides reported by active spectroscopy identified two regions (Sutton Island to Blunts Point and Glasgow to Knockfarril Hill transitions) as areas of compositional interest and show evidence of variations in oxidation conditions. The passive spectra are also shown to be largely in agreement with data from Chemistry and Mineralogy, another instrument on Curiosity which provides mineralogical analysis of powdered samples. Key Points: Principal component and spectral parameter analysis of Chemistry and Camera (ChemCam) passive spectra highlight four spectral end‐members in Mt. Sharp group rocksA decrease in the near‐infrared slope is seen in the Hutton interval, suggesting a changing depositional environment or enhanced diagenesisBedrock containing Mg‐sulfates and Ca‐sulfate cements are highlighted in a multivariate survey of ChemCam passive spectra [ABSTRACT FROM AUTHOR]
- Published
- 2023
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34. Validation of claims algorithms for progression to metastatic cancer in patients with breast, non-small cell lung, and colorectal cancer
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Beth L. Nordstrom, Jason C. Simeone, Karen G. Malley, Kathy H. Fraeman, Zandra eKlippel, Mark eDurst, John H. Page, and Hairong eXu
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oncology ,Cancer Progression ,Random forests ,Metastatic cancer ,claims algorithm ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background: Validated algorithms for identifying progression to metastatic cancer could permit the use of administrative claims databases for research in this area.Objective: To identify simple algorithms that could accurately detect cancer progression to metastatic breast, non-small cell lung, and colorectal cancer using medical and pharmacy claims data.Methods: Adults with stage I–III breast, non-small cell lung cancer (NSCLC), or colorectal cancer (CRC) in the Geisinger Health System from 2004–2011 were selected. Evidence of progression was extracted via manual chart review as the reference standard. In addition to secondary malignancy diagnosis (ICD-9 code for metastases), diagnoses, procedures, and treatments were selected with clinician input as indicators of cancer progression. Random forests models provided variable importance scores. In addition to codes for secondary malignancy, several more complex algorithms were constructed and performance measures calculated.Results: Among those with breast cancer (17/502 [3.4%] progressed), the performance of a secondary malignancy code was suboptimal (sensitivity: 64.7%; specificity: 86.0%; positive predictive value [PPV]: 13.9; negative predictive value [NPV]: 98.6%); requiring malignancy at another site or initiation of immunotherapy increased PPV and specificity but decreased sensitivity. For NSCLC (61/236 [25.8%] progressed) codes for secondary malignancy alone (PPV: 47.4%; NPV: 84.8%; sensitivity: 60.7%; specificity: 76.6%) performed similarly or better than more complex algorithms. For CRC (33/276 [12.0%] progressed), secondary malignancy codes had good specificity (92.7%) and NPV (92.3%) but low sensitivity (42.4%) and PPV (43.8%); an algorithm with change in chemotherapy increased sensitivity but decreased other metrics.Conclusions: Selected algorithms performed similarly to the presence of a secondary tumor diagnosis code, with low sensitivity/PPV and higher specificity/NPV. Accurate identification of cancer progression likely requires verification through chart review.
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- 2016
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35. Hospital costs for treatment of acute heart failure: economic analysis of the REVIVE II study
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de Lissovoy, Greg, Fraeman, Kathy, Teerlink, John R., Mullahy, John, Salon, Jeff, Sterz, Raimund, Durtschi, Amy, and Padley, Robert J.
- Published
- 2010
36. Incidence rates for thromboembolic, bleeding and hepatic outcomes in patients undergoing hip or knee replacement surgery
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LANES, S., FRAEMAN, K., MEYERS, A., IVES, J. WOOD, and HUANG, H.‐Y.
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- 2011
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37. The Curiosity Rover's Exploration of Glen Torridon, Gale Crater, Mars: An Overview of the Campaign and Scientific Results.
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Bennett, Kristen A., Fox, Valerie K., Bryk, Alex, Dietrich, William, Fedo, Christopher, Edgar, Lauren, Thorpe, Michael T., Williams, Amy J., Wong, Gregory M., Dehouck, Erwin, McAdam, Amy, Sutter, Brad, Millan, Maëva, Banham, Steven G., Bedford, Candice C., Bristow, Thomas, Fraeman, Abigail, Vasavada, Ashwin R., Grotzinger, John, and Thompson, Lucy
- Subjects
GALE Crater (Mars) ,MARS rovers ,GEOLOGICAL formations ,LAKE sediments ,MARS (Planet) - Abstract
The Mars Science Laboratory rover, Curiosity, explored the clay mineral‐bearing Glen Torridon region for 1 Martian year between January 2019 and January 2021, including a short campaign onto the Greenheugh pediment. The Glen Torridon campaign sought to characterize the geology of the area, seek evidence of habitable environments, and document the onset of a potentially global climatic transition during the Hesperian era. Curiosity roved 5 km in total throughout Glen Torridon, from the Vera Rubin ridge to the northern margin of the Greenheugh pediment. Curiosity acquired samples from 11 drill holes during this campaign and conducted the first Martian thermochemolytic‐based organics detection experiment with the Sample Analysis at Mars instrument suite. The lowest elevations within Glen Torridon represent a continuation of lacustrine Murray formation deposits, but overlying widespread cross bedded sandstones indicate an interval of more energetic fluvial environments and prompted the definition of a new stratigraphic formation in the Mount Sharp group called the Carolyn Shoemaker formation. Glen Torridon hosts abundant phyllosilicates yet remains compositionally and mineralogically comparable to the rest of the Mount Sharp group. Glen Torridon samples have a great diversity and abundance of sulfur‐bearing organic molecules, which are consistent with the presence of ancient refractory organic matter. The Glen Torridon region experienced heterogeneous diagenesis, with the most striking alteration occurring just below the Siccar Point unconformity at the Greenheugh pediment. Results from the pediment campaign show that the capping sandstone formed within the Stimson Hesperian aeolian sand sea that experienced seasonal variations in wind direction. Plain Language Summary: The Mars Science Laboratory rover, Curiosity, explored a valley called Glen Torridon on the lower slopes of a sedimentary mountain within Gale crater, Mars, between January 2019 and January 2021. The rocks within this shallow valley are part of a sequence of rock layers whose mineral composition could imply a transition from a wetter to drier environment more than 3 billion years ago. This paper reports on the exploration campaign designed to understand the local geology, document evidence of past climate change, and investigate if the ancient environments may have been amenable to biological activity. Curiosity found that many rocks were deposited in the bottom of a lake, but also that river deposits occur frequently in this area, suggesting that the environmental conditions changed through time. Curiosity observed evidence for multiple cycles of water interacting with the sediments that chemically changed the elemental and mineralogical compositions of the rock layers. Curiosity collected 11 drill holes over the course of the campaign and found abundant clay minerals, as predicted, as well as a wide variety of organic molecules, suggesting that the ancient environment contained many of the necessary conditions to support life. Key Points: Sedimentary facies within Glen Torridon record a transition from low‐energy lacustrine mudstones to higher‐energy fluvial sandstonesGlen Torridon hosts the highest clay mineral abundances observed thus far by Mars Science Laboratory (MSL) while remaining in family with the Mount Sharp groupGlen Torridon drill samples contain the greatest diversity of organic compounds yet detected by the MSL mission [ABSTRACT FROM AUTHOR]
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- 2023
- Full Text
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38. Surgical site infection: Incidence and impact on hospital utilization and treatment costs
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de Lissovoy, Gregory, Fraeman, Kathy, Hutchins, Valerie, Murphy, Denise, Song, David, and Vaughn, Brian B.
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- 2009
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39. An improvement to the volcano-scan algorithm for atmospheric correction of CRISM and OMEGA spectral data
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McGuire, Patrick C., Bishop, Janice L., Brown, Adrian J., Fraeman, Abigail A., Marzo, Giuseppe A., Frank Morgan, M., Murchie, Scott L., Mustard, John F., Parente, Mario, Pelkey, Shannon M., Roush, Ted L., Seelos, Frank P., Smith, Michael D., Wendt, Lorenz, and Wolff, Michael J.
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- 2009
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40. Mineralogy of a Possible Ancient Lakeshore in the Sutton Island Member of Mt. Sharp, Gale Crater, Mars, From Mastcam Multispectral Images.
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Haber, James T., Horgan, Briony, Fraeman, Abigail A., Johnson, Jeffrey R., Bell, Jim F., Rice, Melissa S., Seeger, Christina, Mangold, Nicolas, Thompson, Lucy, Wellington, Danika, Cloutis, Ed, and Jacob, Samantha
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GALE Crater (Mars) ,MULTISPECTRAL imaging ,MINERALOGY ,MARS rovers ,BEDROCK ,LUNAR craters ,CLAY - Abstract
The Curiosity rover on the Mars Science Laboratory mission has found extensive evidence that Gale crater once hosted a habitable lacustrine environment; however, there are remaining questions about the chemistry and duration of the lake and the nature of the climate at the time. In this study, we use Mastcam multispectral data to investigate the mineralogy of the Sutton Island member of the Murray formation, a part of the basal layers of Mt. Sharp, which consists of heterolithic mudstone and sandstone that are distinct from the finely laminated mudstones that dominate much of the Murray. Sutton Island includes at least one instance of desiccation cracks, indicative of subaerial exposure, and uniquely irregular diagenetic features that may be related to local bedrock permeability. These features suggest that Sutton Island experienced a complex history of deposition and diagenesis which may be crucial for understanding changing water‐rock interactions within Gale. We find that most Mastcam bedrock spectra in this region lack the absorptions associated with hematite found throughout the Murray, and instead show deeper absorptions shifted toward longer wavelengths that are more consistent with Fe‐smectites such as nontronite. Elemental chemistry from ChemCam supports this interpretation, as SiO, MgO, Li, and the chemical index of alteration are elevated in this region. Combined with observations of bedrock sedimentology, this suggests that Sutton Island was deposited in a nearshore or low stand environment, and we hypothesize that the clay minerals were produced in this region due to sub‐aerial exposure and weathering in a semi‐arid climate. Plain Language Summary: The Curiosity rover on the Mars Science Laboratory mission has found extensive evidence that Gale crater once hosted a habitable lake environment; however, there are remaining questions about the chemistry and timing of the lake and the nature of the climate at the time. In this study, we use Mastcam data to investigate the composition of the Sutton Island member of the Murray formation, which consists of mixed fine and coarse grained rocks that are distinct from the very fine‐grained rocks that dominate much of the Murray. Sutton Island includes mudcracks, indicative of surface exposure, and irregular alteration features that may be related to local bedrock differences. These features suggest that Sutton Island experienced a complex history of deposition and alteration which may be crucial for understanding changing water‐rock interactions within Gale. We find that most bedrock in this region lack features associated with hematite found throughout the Murray, and instead show features that are more consistent with clay minerals. Combined with observations of mudcracks and chemistry data, this suggests that Sutton Island was deposited in a nearshore environment, and we hypothesize that the clays were produced in this region due to surface exposure and weathering in a semi‐arid climate. Key Points: Mastcam multispectral data in Sutton Island exhibit bands >900 nm consistent with Fe/Mg‐clay minerals like nontroniteSutton Island was deposited in a lowstand/nearshore environment and exposed to more subaerial weathering than the nearby MurrayThe presence of abundant clay minerals in Sutton Island significantly reduced fluid flow and alteration during later diagenesis [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
41. Geology and Stratigraphic Correlation of the Murray and Carolyn Shoemaker Formations Across the Glen Torridon Region, Gale Crater, Mars.
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Fedo, C. M., Bryk, A. B., Edgar, L. A., Bennett, K. A., Fox, V. K., Dietrich, W. E., Banham, S. G., Gupta, S., Stack, K. M., Williams, R. M. E., Grotzinger, J. P., Stein, N. T., Rubin, D. M., Caravaca, G., Arvidson, R. E., Hughes, M. N., Fraeman, A. A., Vasavada, A. R., Schieber, J., and Sutter, B.
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STRATIGRAPHIC geology ,GALE Crater (Mars) ,STRATIGRAPHIC correlation ,GEOLOGICAL cross sections ,MARS (Planet) ,IMPACT craters ,LUNAR craters - Abstract
The Glen Torridon (GT) region within Gale crater, Mars, occurs in contact with the southern side of Vera Rubin ridge (VRR), a well‐defined geomorphic feature that is comparatively resistant to erosion. Prior to detailed ground‐based investigation of GT, its geologic relationship with VRR was unknown. Distinct lithologic subunits within the Jura member (Murray formation), which forms the upper part of VRR, made it possible to be also identified within GT. This indicates that the strata pass across the geomorphic divide between regions. Furthermore, the cross‐bedded lower part of the overlying Knockfarril Hill member (Carolyn Shoemaker formation) also occurs within both VRR and GT. Correlation of both units demonstrates that the strata form a continuous stratigraphic succession regardless of large‐scale geomorphic expression. The lithologic change from mudstone (Jura member) to cross‐bedded sandstone (Knockfarril Hill member) heralds a significant shift in paleoenvironment from lacustrine to fluvial. The upper part of the Knockfarril Hill member consists of interbedded mudstone and sandstone that transitions to the overlying finely laminated mudstone of the Glasgow member, and a return to lacustrine deposition. In GT, the Stimson formation unconformably overlies the Glasgow member, where it demarks the southern boundary of GT. Contacts for each stratigraphic unit were defined and transferred to a high‐resolution image base to make a geologic map and cross sections perpendicular to the NE strike. Stratal dips cannot exceed 2° NW to retain the positions of stratigraphic units in the locations they are exposed throughout GT. Plain Language Summary: The Mars Science Laboratory Curiosity rover explored a region called Glen Torridon (GT) that is located on the northwest side of a large sedimentary central mound (Mount Sharp) within Gale crater. This study analyzed the rocks within GT to (a) identify the sedimentary features, (b) determine if or how the sedimentary layers correlate between the Vera Rubin ridge (VRR) and GT regions, (c) interpret ancient environments, (d) generate a geologic map, and (e) discuss the relationship between topography and the exposure of sedimentary layers. Even though the VRR and GT regions are very different in present‐day geomorphology, sedimentary layers correlate across the two regions indicating that the layers belong to a continuous sedimentary succession. Cross‐bedded sandstones of the Knockfarril Hill member represent a change to fluvial from the underlying lake and lake‐margin deposits of the Jura member, which represents a major shift in depositional environment. Packages of layers have distinct characteristics, which allows their distribution to be represented on a map. A geologic cross section limits the tilt of the layers to less than two degrees. We find that caution must be taken when attempting to derive primary stratigraphy only using datasets acquired from orbital platforms. Key Points: Cross‐bedded Knockfarril Hill member strata overlie mudstone of the Jura member indicating an environmental change from lake to fluvialA geologic map of Glen Torridon (GT) made using lithologically defined stratigraphic units shows that strata dip two degrees or less to the NNWStratigraphic units pass from Vera Rubin ridge into GT indicating that strata continue through a major geomorphic boundary [ABSTRACT FROM AUTHOR]
- Published
- 2022
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- View/download PDF
42. Subsurface water and clay mineral formation during the early history of Mars
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Ehlmann, Bethany L., Mustard, John F., Murchie, Scott L., Bibring, Jean-Pierre, Meunier, Alain, Fraeman, Abigail A., and Langevin, Yves
- Published
- 2011
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43. Adherence to guidelines for use of erythropoiesis-stimulating agents in patients with chemotherapy-induced anemia: Results of a retrospective study of an electronic medical-records database in the United States, 2002–2006
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Luo, Weixiu, Nordstrom, Beth L., Fraeman, Kathy, Nordyke, Robert, Ranganathan, Gayatri, Linz, Heather E., Winterkorn, Anna, Stokes, Michael, Ross, Susan D., and Knopf, Kevin
- Published
- 2008
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44. The influence of mantle melting on the evolution of Mars
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Fraeman, Abigail A. and Korenaga, Jun
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Mars (Planet) -- Analysis ,Evolution -- Analysis ,Astronomy -- Analysis ,Lithosphere -- Analysis ,Dehydration (Physiology) -- Analysis ,Earth -- Mantle ,Earth -- Analysis ,Astronomy ,Earth sciences - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2010.06.030 Byline: Abigail A. Fraeman, Jun Korenaga Keywords: Mars, Interior; Thermal histories; Mars, Surface Abstract: We present a parameterized convection model of Mars by incorporating a new heat-flow scaling law for stagnant-lid convection, to better understand how the evolution of Mars may be affected by mantle melting. Melting in the mantle during convection leads to the formation of a compositionally buoyant lithosphere, which may also be intrinsically more viscous by dehydration. The consequences of these melting effects on the evolution of terrestrial planets have not been explored before. The temporal evolution of crust and lithospheric mantle is modeled in a self-consistent manner considering mantle melting, convective instability, and the rewetting of dehydrated lithosphere from below by hydrogen diffusion. Though the effect of compositional buoyancy turns out to be minimal, the introduction of viscosity contrast between wet and dry mantle can considerably slow mantle cooling and sometimes lead to non-monotonic core cooling. Furthermore, with or without dehydration stiffening, our model predicts that the martian mantle must have been degassed more extensively (>80%) than previously suggested ( Author Affiliation: Department of Geology and Geophysics, Yale University, New Haven, CT 06520, USA Article History: Received 28 October 2009; Revised 16 June 2010; Accepted 21 June 2010
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- 2010
45. Disruptions in Liver Function among Cancer Patients and Patients Treated with Tyrosine Kinase Inhibiting Drugs: Comparisons of Two Population-Based Databases
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Sarah H. Landis, Beth L. Nordstrom, Leah B. Sansbury, Sumitra Shantakumar, Samantha A. St. Laurent, Kathy H. Fraeman, and Jeanenne J. Nelson
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Medicine - Abstract
Liver toxicity is a recognized adverse event associated with small molecule tyrosine kinase inhibitors (TKIs). Electronic Medical Record (EMR) databases offer the most precise data to investigate the rate of liver function test (LFT) elevations; however, they can be limited in sample size and costly to access and analyze. Health insurance claims databases often contain larger samples sizes but may lack key health information. We evaluated the feasibility of utilizing a large claims database to calculate incidence rates (IRs) of LFT elevations among a general cohort of cancer patients and a cohort of patients treated with TKIs by comparing the results to a “gold standard” oncology-specific EMR database. IRs for the TKI cohorts were very similar between the two databases; however, IRs were higher in the EMR database for the cancer cohorts. Possible explanations for these differences include lack of specificity when defining a cancer case, poor capture of laboratory data, or inaccurate assessment of person-time in the insurance claims database. This study suggests that insurance claims data may provide reliable results when investigating liver toxicities associated with oncology drug exposure; however, there are limitations when assessing laboratory outcomes for cohorts defined solely by disease status.
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- 2013
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46. Incidence of New-Onset Hypertension in Cancer Patients: A Retrospective Cohort Study
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Kathy H. Fraeman, Beth L. Nordstrom, Weixiu Luo, Sarah H. Landis, and Sumitra Shantakumar
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
This retrospective cohort study was conducted to estimate incidence rates of new-onset hypertension in adult cancer patients identified from the Varian Medical Oncology outpatient database. Incidence rates of increasing levels of hypertension severity were calculated overall and for periods of chemotherapy exposure and nonexposure. Cox models sought predictors of new-onset hypertension severity among baseline and chemotherapy exposure variables. New-onset hypertension was observed in about one-third of 25,090 patients with various cancer types. The incidence rates (IR) of severe and crisis-level hypertension, respectively, were the highest in patients with gastric (18.5 cases per 100 person-years (PY), 5.6 per 100 PY) and ovarian cancer (20.2 per 100 PY, 4.8 per 100 PY). The highest IR of moderate hypertension was observed in patients with renal cancer (46.7 per 100 PY). Across all cancers, chemotherapy exposure was associated with a 2–3.5-fold increase in risk of any degree of hypertension compared to periods of no chemotherapy; higher hypertension levels showed greater variability in relative risks by type and line of therapy but indicated an overall increase associated with chemotherapy exposure. These results help to elucidate the factors influencing HTN among cancer patients and the incidence of HTN relative to chemotherapy exposure.
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- 2013
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47. Real-World Treatment Patterns of Antiviral Prophylaxis for Cytomegalovirus Among Adult Kidney Transplant Recipients: A Linked USRDS-Medicare Database Study.
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Raval, Amit D., Ganz, Michael L., Fraeman, Kathy, Lorden, Andrea L., Saravanan, Shanmugapriya, Yuexin Tang, and Santos, Carlos A. Q.
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KIDNEY transplantation ,CYTOMEGALOVIRUSES ,PREVENTIVE medicine ,DATABASES ,ADULTS - Abstract
Limited data exist on cytomegalovirus (CMV) antiviral treatment patterns among kidney transplant recipients (KTRs). Using United States Renal Database System registry data and Medicare claims (1 January 2011-31 December 2017), we examined CMV antiviral use in 22,878 KTRs who received their first KT from 2011 to 2016. Three-quarters of KTRs started CMV prophylaxis (85.8% of high-, 82.4% of intermediate-, and 32.1% of low-risk KTRs). Median time to prophylaxis discontinuation was 98, 65, and 61 days for high-, intermediate-, and low-risk KTRs, respectively. Factors associated with receiving CMV prophylaxis were high-risk status, diabetes, receipt of a well-functioning kidney graft, greater time on dialysis before KT, panel reactive antibodies ≥80%, and use of antithymocyte globulin, alemtuzumab, and tacrolimus. KTRs were more likely to discontinue CMV prophylaxis if they developed leukopenia/neutropenia, had cardiovascular disease, or received their kidney from a deceased donor. These findings suggest that adherence to the recommended duration of CMV-prophylaxis for high and intermediate-risk patients is suboptimal, and CMV prophylaxis is overused in lowrisk patients. [ABSTRACT FROM AUTHOR]
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- 2022
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48. Spectral Diversity of Rocks and Soils in Mastcam Observations Along the Curiosity Rover's Traverse in Gale Crater, Mars.
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Rice, Melissa S., Seeger, Christina, Bell, Jim, Calef, Fred, St. Clair, Michael, Eng, Alivia, Fraeman, Abigail A., Hughes, Cory, Horgan, Briony, Jacob, Samantha, Johnson, Jeff, Kerner, Hannah, Kinch, Kjartan, Lemmon, Mark, Million, Chase, Starr, Mason, and Wellington, Danika
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GALE Crater (Mars) ,SCIENTIFIC apparatus & instruments ,CURIOSITY ,IMPACT craters ,MARS (Planet) ,SOILS ,LUNAR craters - Abstract
The Mars Science Laboratory Curiosity rover has explored over 400 m of vertical stratigraphy within Gale crater to date. These fluvio‐deltaic, lacustrine, and aeolian strata have been well‐documented by Curiosity's in situ and remote science instruments, including the Mast Camera (Mastcam) pair of multispectral imagers. Mastcam visible to near‐infrared spectra can broadly distinguish between iron phases and oxidation states, and in combination with chemical data from other instruments, Mastcam spectra can help constrain mineralogy, depositional origin, and diagenesis. However, no traverse‐scale analysis of Mastcam multispectral data has yet been performed. We compiled a database of Mastcam spectra from >600 multispectral observations and quantified spectral variations across Curiosity's traverse through Vera Rubin ridge (sols 0–2302). From principal component analysis and an examination of spectral parameters, we identified nine rock spectral classes and five soil spectral classes. Rock classes are dominated by spectral differences attributed to hematite and other oxides (due to variations in grain size, composition, and abundance) and are mostly confined to specific stratigraphic members. Soil classes fall along a mixing line between soil spectra dominated by fine‐grained Fe‐oxides and those dominated by olivine‐bearing sands. By comparing trends in soil versus rock spectra, we find that locally derived sediments are not significantly contributing to the spectra of soils. Rather, varying contributions of dark, mafic sands from the active Bagnold Dune field is the primary spectral characteristic of soils. These spectral classes and their trends with stratigraphy provide a basis for comparison in Curiosity's ongoing exploration of Gale crater. Plain Language Summary: The Curiosity rover's Mastcam instrument is a pair of cameras that take images in visible and near‐infrared wavelengths. Mastcam spectra can distinguish between different types of iron‐bearing minerals. During Curiosity's traverse through a variety of sedimentary rock types in Gale crater, Mars, the rover has acquired more than 600 Mastcam multispectral observations, but no previous studies have analyzed the full data set. In this study, we compiled a database of Mastcam spectra from the first 2302 sols (Martian days) of Curisoity's mission and analyzed spectral trends across the traverse. We define nine classes of spectra for rocks and five classes of spectra for soils, and we observe that different classes occur in different locations. The major spectral differences are due to the mineral hematite and other iron oxides. By comparing the trends in rock spectra to nearby soils across the traverse, we find that the soils are not made of the same minerals as the local rocks, but are dominated by sands from the active Bagnold Dune field. These spectral classes and their trends will be a basis of comparison for Curiosity's ongoing exploration of Gale crater. Key Points: The diversity in Mastcam multispectral data from sols 0–2302 is encapsulated by nine rock spectral classes and five soil spectral classesThe major spectral differences in Mastcam spectra across Curiosity's traverse are attributable to hematite and other Fe‐oxidesComparisons of soil versus rock spectra indicate that locally‐derived sediments are not significantly contributing to the spectra of soils [ABSTRACT FROM AUTHOR]
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- 2022
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49. Orbital and In‐Situ Investigation of Periodic Bedrock Ridges in Glen Torridon, Gale Crater, Mars.
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Stack, Kathryn M., Dietrich, William E., Lamb, Michael P., Sullivan, Robert J., Christian, John R., Newman, Claire E., O'Connell‐Cooper, Catherine D., Sneed, Jonathan W., Day, Mackenzie, Baker, Mariah, Arvidson, Raymond E., Fedo, Christopher M., Khan, Sabrina, Williams, Rebecca M. E., Bennett, Kristen A., Bryk, Alexander B., Cofield, Shannon, Edgar, Lauren A., Fox, Valerie K., and Fraeman, Abigail A.
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GALE Crater (Mars) ,BEDROCK ,MARS (Planet) ,ENVIRONMENTAL history ,WIND erosion ,IMPACT craters - Abstract
Gale crater, the field site for NASA's Mars Science Laboratory Curiosity rover, contains a diverse and extensive record of aeolian deposition and erosion. This study focuses on a series of regularly spaced, curvilinear, and sometimes branching bedrock ridges that occur within the Glen Torridon region on the lower northwest flank of Aeolis Mons, the central mound within Gale crater. During Curiosity's exploration of Glen Torridon between sols ∼2300–3080, the rover drove through this field of ridges, providing the opportunity for in situ observation of these features. This study uses orbiter and rover data to characterize ridge morphology, spatial distribution, compositional and material properties, and association with other aeolian features in the area. Based on these observations, we find that the Glen Torridon ridges are consistent with an origin as wind‐eroded bedrock ridges, carved during the exhumation of Mount Sharp. Erosional features like the Glen Torridon ridges observed elsewhere on Mars, termed periodic bedrock ridges (PBRs), have been interpreted to form transverse to the dominant wind direction. The size and morphology of the Glen Torridon PBRs are consistent with transverse formative winds, but the orientation of nearby aeolian bedforms and bedrock erosional features raise the possibility of PBR formation by a net northeasterly wind regime. Although several formation models for the Glen Torridon PBRs are still under consideration, and questions persist about the nature of PBR‐forming paleowinds, the presence of PBRs at this site provides important constraints on the depositional and erosional history of Gale crater. Plain Language Summary: Wind has played a major role in sculpting the surface of Mars. Gale crater, the field site for NASA's Mars Science Laboratory Curiosity rover since it landed there in 2012, contains a vast and varied record of deposition and erosion by the wind. This study focuses on a series of regularly spaced, generally straight bedrock ridges that occur within the clay‐bearing Glen Torridon region of Aeolis Mons (informally named Mount Sharp) in Gale crater. During Curiosity's exploration of the Glen Torridon region between sols ∼2300–3080 of the mission, the rover drove through this field of ridges, acquiring images and compositional observations along the way. This study characterizes the Glen Torridon ridges using orbiter and rover data to determine their shape, size, occurrence, and relationship to other wind‐formed features in the area. We find that the Glen Torridon ridges were carved by wind into the bedrock of Mount Sharp. Questions remain about the winds that formed these ridges, but this study provides important information about the history and environment of Gale crater and reports the first rover observations of this type of erosional feature on Mars. Key Points: Decameter‐long, regularly spaced bedrock ridges oriented northeast‐southwest occur throughout the Glen Torridon region of Aeolis MonsGlen Torridon ridges cross‐cut elevation contours and bedding, exhibit bifurcations, and are disrupted by small impact cratersGlen Torridon ridges are erosional periodic bedrock ridges whose formation places erosional and depositional constraints on Aeolis Mons [ABSTRACT FROM AUTHOR]
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- 2022
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50. The X-Ray Spectrometer on the MESSENGER Spacecraft
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Schlemm, II, Charles E., Starr, Richard D., Ho, George C., Bechtold, Kathryn E., Hamilton, Sarah A., Boldt, John D., Boynton, William V., Bradley, Walter, Fraeman, Martin E., Gold, Robert E., Goldsten, John O., Hayes, John R., Jaskulek, Stephen E., Rossano, Egidio, Rumpf, Robert A., Schaefer, Edward D., Strohbehn, Kim, Shelton, Richard G., Thompson, Raymond E., Trombka, Jacob I., and Williams, Bruce D.
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- 2007
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