Olathe, KS, United States
Olathe, KS, United States

MidAmerica Nazarene University is a Christian liberal arts college in Olathe, Kansas, United States. It was established in 1966 by the Church of the Nazarene. Wikipedia.


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LAWRENCE -- In 2016, researchers published "slam dunk" evidence, based on iron-60 isotopes in ancient seabed, that supernovae buffeted the Earth -- one of them about 2.6 million years ago. University of Kansas researcher Adrian Melott, professor of physics and astronomy, supported those findings in Nature with an associated letter, titled "Supernovae in the neighborhood." Melott has followed up since those findings with an examination of the effects of the supernovae on Earth's biology. In new research to appear in Astrophysical Journal, the KU researcher and colleagues argue the estimated distance of the supernova thought to have occurred roughly 2.6 million years ago should be cut in half. "There's even more evidence of that supernova now," he said. "The timing estimates are still not exact, but the thing that changed to cause us to write this paper is the distance. We did this computation because other people did work that made a revised distance estimate, which cut the distance in half. But now, our distance estimate is more like 150 light years." A supernova exploding at such a range probably wouldn't touch off mass extinctions on Earth, Melott said. "People estimated the 'kill zone' for a supernova in a paper in 2003, and they came up with about 25 light years from Earth," he said. "Now we think maybe it's a bit greater than that. They left some effects out or didn't have good numbers, so now we think it may be a bit larger distance. We don't know precisely, and of course it wouldn't be a hard-cutoff distance. It would be a gradual change. But we think something more like 40 or 50 light years. So, an event at 150 light years should have some effects here but not set off a mass extinction." In addition to its distance, interstellar conditions at the time of a supernova would influence its lethality to biology on Earth. "Cosmic rays like to travel along magnetic field lines," Melott said. "They don't like to cut across magnetic field lines as they experience forces to stop them from doing that. If there's a magnetic field, we don't know its orientation, so it can either create a superhighway for cosmic ray, or it could block them. The main interesting case did not assume the superhighway. It assumed that much of the magnetic field was blasted out by a series of supernovae, which made the Local Bubble -- and we and the most recent supernovae were inside. This is a weak, disordered magnetic field. The best analogy I can think of is more like off-road driving." In such a case, the authors think cosmic rays from the supernova at 150 light years would have penetrated to Earth's lower atmosphere. "This is a much stronger thing," he said. "The cosmic rays from the supernova would be getting down into the lower atmosphere -- having an effect on the troposphere. All kinds of elementary particles are penetrating from altitudes of 45-10 miles, and many muons get to the ground. The effect of the muons is greater -- it's not overwhelming, but imagine every organism on Earth gets the equivalent of several CT scans per year. CT scans have some danger associated with them. Your doctor wouldn't recommend a CT scan unless you really needed it." Melott said cancer and mutations would be the most obvious consequences for Earth's biology of a supernova's cosmic rays. With his co-authors -- B.C. Thomas of Washburn University (2005 KU physics doctoral graduate and recent winner of the A. Roy Myers Excellence in Research Award), M. Kachelrieß of Institutt for fysikk in Norway, D.V. Semikoz of the Observatoire de Paris, Sorbonne Paris Cite in France and the National Research Nuclear University in Moscow, and A.C. Overholt (2013 KU physics doctoral graduate) of MidAmerica Nazarene University -- Melott looked at the fossil record in Africa, the most geographically stable continent on earth during the Pleistocene, when a supernova was likely to have occurred. "There isn't a mass extinction, but there is kind of a lot of extinction going on at that time and species turnover," he said. "It's not quite severe enough to call it a mass extinction. There is some effect possibly connected to the supernova. That's more difficult to say because there are many competing effects. Even in Africa you have climate change, and you don't know if climate change is causing the effects you see or if a supernova has something to do with the climate change." In addition to cosmic rays, the team found a supernova would have caused blue light to shine in the sky at night for about a month. "That's been shown to be a fairly bad thing for almost all living organisms," Melott said. "It throws off sleep and messes up your melatonin production. I would never want a blue LED alarm clock in my bedroom, for example. Blue LED streetlights have been shown to have bad effects in animals, causing behavioral changes. But this effect would only last a month or so. I think you would never see evidence in the fossil record." Atmospheric ionization would have been a more serious effect from a supernova, according to the KU researcher. "Atmospheric ionization can help lightning get started," Melott said. "When a cosmic ray comes down, it makes a path through the atmosphere, where it knocks electrons out of atoms, and that makes a pathway for lightning to get started. We'd expect to see a big increase with cloud-to-ground lightning. That would be good for some organisms and bad for others. Lightning is the number one cause of wildfires other than humans. So, we'd expect a whole lot more wildfires, and that could change the ecology of different regions, such as a loss of tree cover in northeast Africa, which could even have something to do with human evolution. The Great Plains has recently been largely kept grass-covered by a bunch of wildfires. A big increase in lightning would also mean a big increase in nitrate coming out of the rain, and that would act like fertilizer." Indeed, Melott said 2.6 million years ago there was in Africa a loss of tree cover and increase in grassland, possibly attributable to lightning-driven wildfires. "We think it's possible that the cosmic rays may have had something to do with that," he said. Melott added he's often asked by people if they should fear a supernova exploding close to Earth today. "I tell them they should worry about global warming and nuclear war, not this stuff," he said. "There's nothing close enough to cause this kind of event in the very near future." The closest potential supernova is Betelgeuse, about 600 light years away, according to Melott. "It's much further away than this one we've been talking about," he said. "It's close enough to be spectacular in the sense that it would be bright and you'd see it in daytime, but there'd be no harmful effects."


News Article | May 12, 2017
Site: astrobiology.com

In 2016, researchers published "slam dunk" evidence, based on iron-60 isotopes in ancient seabed, that supernovae buffeted the Earth One of these supernovae was about 2.6 million years ago. University of Kansas researcher Adrian Melott, professor of physics and astronomy, supported those findings in Nature with an associated letter, titled "Supernovae in the Neighborhood" [http://www.nature.com/nature/journal/v532/n7597/full/532040a.html]. Melott has followed up since those findings with an examination of the effects of the supernovae on Earth's biology. In new research to appear in Astrophysical Journal, the KU researcher and colleagues argue the estimated distance of the supernova thought to have occurred roughly 2.6 million years ago should be cut in half. "There's even more evidence of that supernova now," he said. "The timing estimates are still not exact, but the thing that changed to cause us to write this paper is the distance. We did this computation because other people did work that made a revised distance estimate, which cut the distance in half. But now, our distance estimate is more like 150 light-years." A supernova exploding at such a range probably wouldn't touch off mass extinctions on Earth, Melott said. "People estimated the 'kill zone' for a supernova in a paper in 2003, and they came up with about 25 light-years from Earth," he said. "Now we think maybe it's a bit greater than that. They left some effects out or didn't have good numbers, so now we think it may be a bit larger distance. We don't know precisely, and of course it wouldn't be a hard-cutoff distance. It would be a gradual change. But we think something more like 40 or 50 light-years. So, an event at 150 light-years should have some effects here but not set off a mass extinction." In addition to its distance, interstellar conditions at the time of a supernova would influence its lethality to biology on Earth. "Cosmic rays like to travel along magnetic field lines," Melott said. "They don't like to cut across magnetic field lines as they experience forces to stop them from doing that. If there's a magnetic field, we don't know its orientation, so it can either create a superhighway for cosmic ray, or it could block them. The main interesting case did not assume the superhighway. It assumed that much of the magnetic field was blasted out by a series of supernovae, which made the Local Bubble -- and we and the most recent supernovae were inside. This is a weak, disordered magnetic field. The best analogy I can think of is more like off-road driving." In such a case, the authors think cosmic rays from the supernova at 150 light-years would have penetrated to Earth's lower atmosphere. "This is a much stronger thing," he said. "The cosmic rays from the supernova would be getting down into the lower atmosphere -- having an effect on the troposphere. All kinds of elementary particles are penetrating from altitudes of 45-10 miles, and many muons get to the ground. The effect of the muons is greater -- it's not overwhelming, but imagine every organism on Earth gets the equivalent of several CT scans per year. CT scans have some danger associated with them. Your doctor wouldn't recommend a CT scan unless you really needed it." Melott said cancer and mutations would be the most obvious consequences for Earth's biology of a supernova's cosmic rays. With his co-authors -- B.C. Thomas of Washburn University (2005 KU physics doctoral graduate and recent winner of the A. Roy Myers Excellence in Research Award), M. Kachelrieß of Institutt for fysikk in Norway, D.V. Semikoz of the Observatoire de Paris, Sorbonne Paris Cite in France and the National Research Nuclear University in Moscow, and A.C. Overholt (2013 KU physics doctoral graduate) of MidAmerica Nazarene University -- Melott looked at the fossil record in Africa, the most geographically stable continent on Earth during the Pleistocene, when a supernova was likely to have occurred. "There isn't a mass extinction, but there is kind of a lot of extinction going on at that time and species turnover," he said. "It's not quite severe enough to call it a mass extinction. There is some effect possibly connected to the supernova. That's more difficult to say because there are many competing effects. Even in Africa you have climate change, and you don't know if climate change is causing the effects you see or if a supernova has something to do with the climate change." In addition to cosmic rays, the team found a supernova would have caused blue light to shine in the sky at night for about a month. "That's been shown to be a fairly bad thing for almost all living organisms," Melott said. "It throws off sleep and messes up your melatonin production. I would never want a blue LED alarm clock in my bedroom, for example. Blue LED streetlights have been shown to have bad effects in animals, causing behavioral changes. But this effect would only last a month or so. I think you would never see evidence in the fossil record." Atmospheric ionization would have been a more serious effect from a supernova, according to the KU researcher. "Atmospheric ionization can help lightning get started," Melott said. "When a cosmic ray comes down, it makes a path through the atmosphere, where it knocks electrons out of atoms, and that makes a pathway for lightning to get started. We'd expect to see a big increase with cloud-to-ground lightning. That would be good for some organisms and bad for others. Lightning is the number one cause of wildfires other than humans. So, we'd expect a whole lot more wildfires, and that could change the ecology of different regions, such as a loss of tree cover in northeast Africa, which could even have something to do with human evolution. The Great Plains has recently been largely kept grass-covered by a bunch of wildfires. A big increase in lightning would also mean a big increase in nitrate coming out of the rain, and that would act like fertilizer." Indeed, Melott said 2.6 million years ago there was in Africa a loss of tree cover and increase in grassland, possibly attributable to lightning-driven wildfires. "We think it's possible that the cosmic rays may have had something to do with that," he said. Melott added he's often asked by people if they should fear a supernova exploding close to Earth today. "I tell them they should worry about global warming and nuclear war, not this stuff," he said. "There's nothing close enough to cause this kind of event in the very near future." The closest potential supernova is Betelgeuse, about 600 light-years away, according to Melott. "It's much further away than this one we've been talking about," he said. "It's close enough to be spectacular in the sense that it would be bright and you'd see it in daytime, but there'd be no harmful effects." Reference: "A Supernova at 50 pc: Effects on the Earth's Atmosphere and Biota," A. L. Melott et al., 2017, to appear in the Astrophysical Journal [http://apj.aas.org, preprint: https://arxiv.org/abs/1702.04365].


Melott has followed up since those findings with an examination of the effects of the supernovae on Earth's biology. In new research to appear in Astrophysical Journal, the KU researcher and colleagues argue the estimated distance of the supernova thought to have occurred roughly 2.6 million years ago should be cut in half. "There's even more evidence of that supernova now," he said. "The timing estimates are still not exact, but the thing that changed to cause us to write this paper is the distance. We did this computation because other people did work that made a revised distance estimate, which cut the distance in half. But now, our distance estimate is more like 150 light years." A supernova exploding at such a range probably wouldn't touch off mass extinctions on Earth, Melott said. "People estimated the 'kill zone' for a supernova in a paper in 2003, and they came up with about 25 light years from Earth," he said. "Now we think maybe it's a bit greater than that. They left some effects out or didn't have good numbers, so now we think it may be a bit larger distance. We don't know precisely, and of course it wouldn't be a hard-cutoff distance. It would be a gradual change. But we think something more like 40 or 50 light years. So, an event at 150 light years should have some effects here but not set off a mass extinction." In addition to its distance, interstellar conditions at the time of a supernova would influence its lethality to biology on Earth. "Cosmic rays like to travel along magnetic field lines," Melott said. "They don't like to cut across magnetic field lines as they experience forces to stop them from doing that. If there's a magnetic field, we don't know its orientation, so it can either create a superhighway for cosmic ray, or it could block them. The main interesting case did not assume the superhighway. It assumed that much of the magnetic field was blasted out by a series of supernovae, which made the Local Bubble—and we and the most recent supernovae were inside. This is a weak, disordered magnetic field. The best analogy I can think of is more like off-road driving." In such a case, the authors think cosmic rays from the supernova at 150 light years would have penetrated to Earth's lower atmosphere. "This is a much stronger thing," he said. "The cosmic rays from the supernova would be getting down into the lower atmosphere—having an effect on the troposphere. All kinds of elementary particles are penetrating from altitudes of 45-10 miles, and many muons get to the ground. The effect of the muons is greater—it's not overwhelming, but imagine every organism on Earth gets the equivalent of several CT scans per year. CT scans have some danger associated with them. Your doctor wouldn't recommend a CT scan unless you really needed it." Melott said cancer and mutations would be the most obvious consequences for Earth's biology of a supernova's cosmic rays. With his co-authors— B.C. Thomas of Washburn University (2005 KU physics doctoral graduate and recent winner of the A. Roy Myers Excellence in Research Award), M. Kachelrieß of Institutt for fysikk in Norway, D.V. Semikoz of the Observatoire de Paris, Sorbonne Paris Cite in France and the National Research Nuclear University in Moscow, and A.C. Overholt (2013 KU physics doctoral graduate) of MidAmerica Nazarene University—Melott looked at the fossil record in Africa, the most geographically stable continent on earth during the Pleistocene, when a supernova was likely to have occurred. "There isn't a mass extinction, but there is kind of a lot of extinction going on at that time and species turnover," he said. "It's not quite severe enough to call it a mass extinction. There is some effect possibly connected to the supernova. That's more difficult to say because there are many competing effects. Even in Africa you have climate change, and you don't know if climate change is causing the effects you see or if a supernova has something to do with the climate change." In addition to cosmic rays, the team found a supernova would have caused blue light to shine in the sky at night for about a month. "That's been shown to be a fairly bad thing for almost all living organisms," Melott said. "It throws off sleep and messes up your melatonin production. I would never want a blue LED alarm clock in my bedroom, for example. Blue LED streetlights have been shown to have bad effects in animals, causing behavioral changes. But this effect would only last a month or so. I think you would never see evidence in the fossil record." Atmospheric ionization would have been a more serious effect from a supernova, according to the KU researcher. "Atmospheric ionization can help lightning get started," Melott said. "When a cosmic ray comes down, it makes a path through the atmosphere, where it knocks electrons out of atoms, and that makes a pathway for lightning to get started. We'd expect to see a big increase with cloud-to-ground lightning. That would be good for some organisms and bad for others. Lightning is the number one cause of wildfires other than humans. So, we'd expect a whole lot more wildfires, and that could change the ecology of different regions, such as a loss of tree cover in northeast Africa, which could even have something to do with human evolution. The Great Plains has recently been largely kept grass-covered by a bunch of wildfires. A big increase in lightning would also mean a big increase in nitrate coming out of the rain, and that would act like fertilizer." Indeed, Melott said 2.6 million years ago there was in Africa a loss of tree cover and increase in grassland, possibly attributable to lightning-driven wildfires. "We think it's possible that the cosmic rays may have had something to do with that," he said. Melott added he's often asked by people if they should fear a supernova exploding close to Earth today. "I tell them they should worry about global warming and nuclear war, not this stuff," he said. "There's nothing close enough to cause this kind of event in the very near future." The closest potential supernova is Betelgeuse, about 600 light years away, according to Melott. "It's much further away than this one we've been talking about," he said. "It's close enough to be spectacular in the sense that it would be bright and you'd see it in daytime, but there'd be no harmful effects." Explore further: Ancient supernovae buffeted Earth's biology with radiation dose, researcher says More information: "A Supernova at 50 pc: Effects on the Earth's Atmosphere and Biota," A. L. Melott et al., 2017, to appear in the Astrophysical Journal: arxiv.org/abs/1702.04365


News Article | April 17, 2017
Site: www.prweb.com

LearnHowToBecome.org, a leading resource provider for higher education and career information, has used released its list of the best colleges and universities in Kansas for 2017. Of the 23 four-year schools that made the list, Baker University, University of Kansas, Southwestern College, Kansas State University and Newman University scored as the top five. Of the 26 two-year schools that were also included, Dodge City Community College, Garden City Community College, Highland Community College, Hesston College and Neosho County Community College ranked the most highly. A full list of schools is included below. “Kansas’ unemployment rate has remained low over the past year, making it a stable place to begin a career,” said Wes Ricketts, senior vice president of LearnHowToBecome.org. “These Kansas schools have done an exceptional job preparing their students for the job market by providing a quality education and solid academic counseling and resources.” To be included on Kansas’ “Best Colleges” list, schools must be regionally accredited, not-for-profit institutions. Each college is also scored on data that includes career and academic resources, annual alumni earnings 10 years after entering college, availability of financial aid and such additional numbers as graduation rates and student/teacher ratios. Complete details on each college, their individual scores and the data and methodology used to determine the LearnHowToBecome.org “Best Colleges in Kansas” list, visit: Best Four-Year Colleges in Kansas for 2017 include: Baker University Benedictine College Bethany College Bethel College-North Newton Central Christian College of Kansas Emporia State University Fort Hays State University Friends University Kansas State University Kansas Wesleyan University McPherson College MidAmerica Nazarene University Newman University Ottawa University-Kansas City Ottawa University-Ottawa Pittsburg State University Southwestern College Sterling College Tabor College University of Kansas University of Saint Mary Washburn University Wichita State University Best Two-Year Colleges in Kansas for 2017 include: Allen County Community College Barton County Community College Butler Community College Cloud County Community College Coffeyville Community College Colby Community College Cowley County Community College Dodge City Community College Flint Hills Technical College Fort Scott Community College Garden City Community College Hesston College Highland Community College Hutchinson Community College Independence Community College Johnson County Community College Kansas City Kansas Community College Labette Community College Manhattan Area Technical College Neosho County Community College North Central Kansas Technical College Pratt Community College Salina Area Technical College Seward County Community College and Area Technical School Washburn Institute of Technology Wichita Area Technical College About Us: LearnHowtoBecome.org was founded in 2013 to provide data and expert driven information about employment opportunities and the education needed to land the perfect career. Our materials cover a wide range of professions, industries and degree programs, and are designed for people who want to choose, change or advance their careers. We also provide helpful resources and guides that address social issues, financial aid and other special interest in higher education. Information from LearnHowtoBecome.org has proudly been featured by more than 700 educational institutions.


News Article | March 1, 2017
Site: www.prweb.com

The Community for Accredited Online Schools, a leading resource provider for higher education information, has highlighted Kansas’ best colleges and universities with online programs for 2017. A total of 33 schools were recognized for providing top-quality online learning programs. Of the 18 four-year schools that were ranked, University of Kansas, Kansas State University, Baker University, Southwestern University and Wichita State University came in as the top five institutions. Kansas’ top 15 two-year schools were also included, with Dodge City Community College, Barton County Community College, Hutchinson Community College, Johnson County Community College and Kansas City Kansas Community College taking the lead. “Students across the nation are increasingly interested in pursuing an online education, and Kansas is no exception,” said Doug Jones, CEO and founder of AccreditedSchoolsOnline.org. “The schools on our list have proven to offer high quality education options online for students who want a more flexible, accessible certificate or degree program.” To earn a spot on Kansas’ “Best Online Schools” list, these colleges and universities must be public or private not-for-profit entities that are institutionally accredited. Each college is also rated based data points that include graduation rates, student/teacher ratios, student services and financial aid availability. For more details on where each school falls in the rankings and the data and methodology used to determine the lists, visit: The Best Online Four-Year Schools in Kansas for 2017 include the following: Baker University Barclay College Central Christian College of Kansas Emporia State University Fort Hays State University Friends University Kansas State University MidAmerica Nazarene University Newman University Ottawa University Pittsburg State University Southwestern College Sterling College Tabor College University of Kansas University of Saint Mary Washburn University Wichita State University Kansas’ Best Online Two-Year Schools for 2017 include the following: Allen County Community College Barton County Community College Cloud County Community College Coffeyville Community College Colby Community College Cowley County Community College Dodge City Community College Flint Hills Technical College Hutchinson Community College Johnson County Community College Kansas City Kansas Community College Labette Community College Pratt Community College Seward County Community College and Area Technical School Wichita Area Technical College ### About Us: AccreditedSchoolsOnline.org was founded in 2011 to provide students and parents with quality data and information about pursuing an affordable, quality education that has been certified by an accrediting agency. Our community resource materials and tools span topics such as college accreditation, financial aid, opportunities available to veterans, people with disabilities, as well as online learning resources. We feature higher education institutions that have developed online learning programs that include highly trained faculty, new technology and resources, and online support services to help students achieve educational success.


Overholt A.C.,University of Kansas | Overholt A.C.,MidAmerica Nazarene University | Melott A.L.,University of Kansas | Atri D.,Tata Institute of Fundamental Research | Atri D.,Blue Marble Space Institute of Science
Journal of Geophysical Research: Space Physics | Year: 2013

Neutrons contribute a significant radiation dose at commercial passenger airplane altitudes. With cosmic ray energies > 1 GeV, these effects could, in principle, be propagated to ground level. Under current conditions, the cosmic ray spectrum incident on the Earth is dominated by particles with energies < 1 GeV. Astrophysical shocks from events such as supernovae accelerate high-energy cosmic rays (HECRs) well above this range. The Earth is likely episodically exposed to a greatly increased HECR flux from such events. Solar events of smaller energies are much more common and short lived but still remain a topic of interest due to the ground level enhancements they produce. The air showers produced by cosmic rays (CRs) ionize the atmosphere and produce harmful secondary particles such as muons and neutrons. Although the secondary spectra from current day terrestrial cosmic ray flux are well known, this is not true for spectra produced by many astrophysical events. This work shows the results of Monte Carlo simulations quantifying the neutron flux due to CRs at various primary energies and altitudes. We provide here look-up tables that can be used to determine neutron fluxes from proton primaries with kinetic energies of 1 MeV-1 PeV. By convolution, one can compute the neutron flux for any arbitrary CR spectrum. This contrasts with all other similar works, which are spectrum dependent. Our results demonstrate the difficulty in deducing the nature of primaries from the spectrum of ground level neutron enhancements. Key Points Astrophysical events increase cosmic ray flux on the Earth. Our tables which simulate the neutron flux of a variety of astrophysical events This is the first spectrum independent table ©2013. American Geophysical Union. All Rights Reserved.


News Article | November 23, 2016
Site: www.prweb.com

Attorneys Richard Martin and Jerry Wallentine, founders of Martin & Wallentine, are proud to announce they recently sponsored the Olathe Mayor’s Prayer Breakfast, which featured Kansas City Royals General Manager Dayton Moore as a guest speaker, at MidAmerica Nazarene University. The annual Olathe Mayor’s Prayer Breakfast brings all segments of the Olathe community together to share in a morning of spiritual renewal and reflection on the Friday prior to each Thanksgiving. “It was a wonderful event with an impressive turnout of 450 attendees,” said Wallentine. “This was our first year sponsoring the prayer breakfast, and Martin & Wallentine plan on supporting this event in the years to come.” Proceeds from the Olathe Mayor’s Prayer Breakfast benefit the Mayor’s Christmas Tree Fund, which helps children in need during Christmas. “Martin & Wallentine also wanted to support the event’s goal to provide a positive spiritual experience for the leaders in our community,” concluded Martin. “We want to be a beneficial supporter of our community, as we have been in Olathe for many years.” About Martin & Wallentine, LLC Martin & Wallentine specializes in criminal defense and family law in Johnson County, KS. Attorney Jerry Wallentine focuses on criminal defense and is a member of the Kansas Association of Criminal Defense Lawyers and National Association of Criminal Defense Lawyers. Attorney Richard Martin focuses on family law, and 90% of his practice is devoted to litigation. Both attorneys are licensed in Kansas and Missouri. For more information, please call (913) 764-9700, visit http://www.olathe-lawyer.com, or follow them on Facebook. The law office is located at 130 North Cherry Street, Suite 201, Olathe, KS 66061. About the NALA™ The NALA offers small and medium-sized businesses effective ways to reach customers through new media. As a single-agency source, the NALA helps businesses flourish in their local community. The NALA’s mission is to promote a business’ relevant and newsworthy events and achievements, both online and through traditional media. For media inquiries, please call 805.650.6121, ext. 361.


Overholt A.C.,MidAmerica Nazarene University | Melott A.L.,University of Kansas | Atri D.,Blue Marble Space Institute of Science
Journal of Geophysical Research A: Space Physics | Year: 2015

Cosmic rays are known to cause biological effects directly and through ionizing radiation produced by their secondaries. These effects have been detected in airline crews and other specific cases where members of the population are exposed to above average secondary fluxes. Recent work has found a correlation between solar particle events and congenital malformations. In this work we use the results of computational simulations to approximate the ionizing radiation from such events as well as longer-term increases in cosmic ray flux. We find that the amounts of ionizing radiation produced by these events are insufficient to produce congenital malformations under the current paradigm regarding muon ionizing radiation. We believe that further work is needed to determine the correct ionizing radiation contribution of cosmogenic muons. We suggest that more extensive measurements of muon radiation effects may show a larger contribution to ionizing radiation dose than currently assumed. Key Points Solar events produce measurable amounts of ionizing radiation at ground level The ionizing radiation is insufficient to explain the observed phenomena Future work regarding the effects of muons is required ©2015. American Geophysical Union. All Rights Reserved.


Overholt A.C.,University of Kansas | Overholt A.C.,MidAmerica Nazarene University | Melott A.L.,University of Kansas
Earth and Planetary Science Letters | Year: 2013

We explore the idea that detectable excursions in 26Al may arise from direct deposition by any bolide, and excursions in 14C and 10Be abundances in the atmosphere may result from long-period comet impacts. This is very different from the usual processes of production by cosmic rays within Earth's atmosphere. Long-period comets experience greatly increased cosmic ray flux beyond the protection of the sun's magnetic field. We report the computed amount of 14C, 10Be, and 26Al present on long-period comets as a function of comet mass. We find that the amount of nuclide mass on large long-period comets entering the Earth's atmosphere may be sufficient for creating anomalies in the records of 14C and 10Be from past impacts. In particular, the estimated mass of the proposed Younger Dryas comet is consistent with its having deposited sufficient isotopes to account for recorded 14C and 10Be increases at that time. The 26Al/10Be ratio is much larger in extraterrestrial objects than in the atmosphere, and so, we note that measuring this ratio in ice cores is a suitable definitive test for the Younger Dryas impact hypothesis, even if the hypothetical bolide is not a long-period comet and/or did not contribute to the 14C and 10Be increases. © 2013 Elsevier B.V.


Sattley W.M.,MidAmerica Nazarene University | Blankenship R.E.,Washington University in St. Louis
Photosynthesis Research | Year: 2010

The complete annotated genome sequence of Heliobacterium modesticaldum strain Ice1 provides our first glimpse into the genetic potential of the Heliobacteriaceae, a unique family of anoxygenic phototrophic bacteria. H. modesticaldum str. Ice1 is the first completely sequenced phototrophic representative of the Firmicutes, and heliobacteria are the only phototrophic members of this large bacterial phylum. The H. modesticaldum genome consists of a single 3.1-Mb circular chromosome with no plasmids. Of special interest are genomic features that lend insight to the physiology and ecology of heliobacteria, including the genetic inventory of the photosynthesis gene cluster. Genes involved in transport, photosynthesis, and central intermediary metabolism are described and catalogued. The obligately heterotrophic metabolism of heliobacteria is a key feature of the physiology and evolution of these phototrophs. The conspicuous absence of recognizable genes encoding the enzyme ATP-citrate lyase prevents autotrophic growth via the reverse citric acid cycle in heliobacteria, thus being a distinguishing differential characteristic between heliobacteria and green sulfur bacteria. The identities of electron carriers that enable energy conservation by cyclic light-driven electron transfer remain in question. © 2010 Springer Science+Business Media B.V.

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