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Sample records for aa aa aa

  1. Rating AAs.

    ERIC Educational Resources Information Center

    Carter, Susan J.

    2001-01-01

    Why alternative investments? In a word: performance. Many higher education endowment and foundation managers are making increasing commitments to alternative investments, or AAs, in order to obtain higher returns and broader diversification for their investment portfolios than public securities instruments can usually provide. Learn how to handle…

  2. Section AA Pre2004 Fire, Section AA 2009, Section AA, South ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Section A-A Pre-2004 Fire, Section A-A 2009, Section A-A, South Elevation - Boston & Maine Railroad, Berlin Branch Bridge #148.81, Formerly spanning Moose Brook at former Boston & Maine Railroad, Gorham, Coos County, NH

  3. The AAS Workforce Survey

    NASA Astrophysics Data System (ADS)

    Postman, Marc; Norman, D. J.; Evans, N. R.; Ivie, R.

    2014-01-01

    The AAS Demographics Committee, on behalf of the AAS, was tasked with initiating a biennial survey to improve the Society's ability to serve its members and to inform the community about changes in the community's demographics. A survey, based in part on similar surveys for other scientific societies, was developed in the summer of 2012 and was publicly launched in January 2013. The survey randomly targeted 2500 astronomers who are members of the AAS. The survey was closed 4 months later (April 2013). The response rate was excellent - 63% (1583 people) completed the survey. I will summarize the results from this survey, highlighting key results and plans for their broad dissemination.

  4. AAS 228: Welcome!

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Greetings from the 228th American Astronomical Society meeting in San Diego, California! This week, along with a team of fellow authorsfrom astrobites, Iwill bewritingupdates on selectedevents at themeeting and posting twiceeach day. You can follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.If youre at the meeting, come stop by the AAS booth (Booth #211-213) to learn about the newly-announced partnership between AAS and astrobites and pick up some swag.And dont forget to visit the IOP booth in the Exhibit Hall (Booth #223) to learn more about the new corridors for AAS Journals and to pick up a badge pin to representyour corridor!

  5. AAS 227: Welcome!

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Greetings from the 227th American Astronomical Society meeting in Kissimmee, Florida! This week, along with several fellow authors from astrobites, Iwill bewritingupdates on selectedevents at themeeting and posting at the end of each day. You can follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.If youre an author or referee (or plan to be!) and youre here at the meeting, consider joining us at our Author and Referee Workshop on Wednesday in the Tallahassee room, where well be sharingsome of the exciting new features of the AAS journals. You can drop intoeither of the two-hour sessions(10 AM 12 PM or 1 PM 3 PM), and there will be afree buffet lunch at noon.Heres the agenda:Morning SessionTopic Speaker10:00 am 10:05 amIntroductionsJulie Steffen10:05 am 10:35 amChanges at AAS Journals; How to Be a Successful AAS AuthorEthan Vishniac10:35 am 11:00 amThe Peer Review ProcessButler Burton11:00 am 11:15 amAAS Nova: Sharing AAS Authors Research with the Broader CommunitySusanna Kohler11:15 am 11:30 amFixing Software and Instrumentation Publishing: New Paper Styles in AAS JournalsChris Lintott11:30 am 11:45 amMaking Article Writing Easier with the New AASTeX v6.0Greg Schwarz11:45 am 12:00 pmBringing JavaScript and Interactivity to Your AAS Journal FiguresGus MuenchLunch SessionTopic Speaker12:00 pm 12:15 pmUnified Astronomy ThesaurusKatie Frey12:15 pm 12:30 pmAAS/ADS ORCID Integration ToolAlberto Accomazzi12:30 pm 12:45 pmWorldWide Telescope and Video AbstractsJosh Peek12:45 pm 01:00 pmArizona Astronomical Data Hub (AADH)Bryan HeidornAfternoon SessionTopic Speaker01:00 pm 01:05 pmIntroductionsJulie Steffen01:05 pm 01:35 pmChanges at AAS Journals; How to Be a Successful AAS AuthorEthan Vishniac01:35 pm 02:00 pmThe Peer Review ProcessButler Burton02:00 pm 02:15 pmAAS Nova: Sharing AAS Authors Research with the Broader CommunitySusanna Kohler02:15 pm 02:30 pm

  6. AAS Career Services

    NASA Astrophysics Data System (ADS)

    Marvel, Kevin B.

    2012-08-01

    The American Astronomical Society provides substantial programs in the area of Career Services.Motivated by the Society's mission to enhance and share humanity's understanding of the Universe, the AAS provides a central resource for advertising positions, interviewing opportunities at its annual winter meeting and information, workshops and networks to enable astronomers to find employment.The programs of the Society in this area are overseen by an active committee on employment and the AAS Council itself.Additional resources that help characterize the field, its growth and facts about employment such as salaries and type of jobs available are regularly summarized and reported on by the American Institute of Physics.

  7. AAS Oral History Project

    NASA Astrophysics Data System (ADS)

    Buxner, Sanlyn; Holbrook, Jarita; AAS Oral History Team

    2016-06-01

    Now in its fourth year, the AAS Oral History Project has interviewed over 80 astronomers from all over the world. Led by the AAS Historical Astronomy Division (HAD) and partially funded by the American Institute of Physics Niels Bohr Library and ongoing support from the AAS, volunteers have collected oral histories from astronomers at professional meetings starting in 2015, including AAS, DPS, and the IAU general assembly. Each interview lasts one and a half to two hours and focuses on interviewees’ personal and professional lives. Questions include those about one’s family, childhood, strong influences on one’s scientific career, career path, successes and challenges, perspectives on how astronomy is changing as a field, and advice to the next generation. Each interview is audio recorded and transcribed, the content of which is checked with each interviewee. Once complete, interview transcripts are posted online as part of a larger oral history library at https://www.aip.org/history-programs/niels-bohr-library/oral-histories. Future analysis will reveal a rich story of astronomers and will help the community address issues of diversity, controversies, and the changing landscape of science. We are still recruiting individuals to be interviewed from all stages of career from undergraduate students to retired and emeritus astronomers. Contact Jarita Holbrook to schedule an interview or to find out more information about the project (astroholbrook@gmail.com). Also, contact Jarita Holbrook if you would like to become an interviewer for the project.

  8. AAS 227: Day 2

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Editors Note:This week were at the 227th AAS Meeting in Kissimmee, FL. Along with several fellow authors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting at the end of each day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Welcome to Day 2 of the winter American Astronomical Society (AAS) meeting in Kissimmee! Several of us are attending the conference this year, and we will report highlights from each day here on astrobites. If youd like to see more timely updates during the day, we encourage you to follow @astrobites on twitter or search the #aas227 hashtag.Plenary Session: Black Hole Physics with the Event Horizon Telescope (by Susanna Kohler)If anyone needed motivation to wake up early this morning, they got it in the form of Feryal Ozel (University of Arizona) enthralling us all with exciting pictures, videos, and words about black holes and the Event Horizon Telescope. Ozel spoke to a packed room (at 8:30am!) about where the project currently stands, and where its heading in the future.The EHT has pretty much the coolest goal ever: actually image the event horizons of black holes in our universe. The problem is that the largest black hole we can look at (Sgr A*, in the center of our galaxy) has an event horizon size of 50 as. For this kind of resolution roughly equivalent to trying to image a DVD on the Moon! wed need an Earth-sized telescope. EHT has solved this problem by linking telescopes around the world, creating one giant, mm-wavelength effective telescope with a baseline the size of Earth.Besides producing awesome images, the EHT will be able to test properties of black-hole spacetime, the no-hair theorem, and general relativity (GR) in new regimes.Ozel walked us through some of the theory prep work we need to do now in order to get the most science out of the EHT, including devising new

  9. AAS 227: Day 1

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Editors Note:This week were at the 227th AAS Meeting in Kissimmee, FL. Along with several fellow authors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting at the end of each day. Follow along here or at astrobites.com, or catch ourlive-tweeted updates from the @astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Things kicked off last night at our undergraduate reception booth. Thanks to all of you who stopped by we were delightedto have so many people tell us that they already know about and useastrobites, and we were excited to introduce a new cohort of students at AAS to astrobites for the first time.Tuesday morning was the official start of the meeting. Here are just a few of the talks and workshops astrobiters attended today.Opening Address (by Becky Smethurst)The President of the AAS, aka our fearless leader Meg Urry kicked off the meeting this morning at the purely coffee powered hour of 8am this morning. She spoke about the importance of young astronomers at the meeting (heres looking at you reader!) and also the importance of the new Working Group for Accessibility and Disabilities (aka WGAD pronounced like wicked) at the AAS. The Society has made extra effort this year to make the conference accessible to all,a message which was very well received by everyone in attendance.Kavli Lecture: New Horizons Alan Stern (by Becky Smethurst)We were definitely spoilt with the first Plenary lecture at this years conference Alan Stern gave us a a review of the New Horizons mission of the Pluto Fly By (astrobites covered the mission back in July with this post). We were treated to beautiful images, wonderful results and a foray into geology.Before (Hubble) and after #NewHorizons. #thatisall #science #astro alanstern #aas227 pic.twitter.com/kkMt6RsSIR Science News (@topsciencething) January 5, 2016Some awesome facts from the lecture that blew my mind:New Horizons is now 2AU (!) beyond Pluto

  10. AAS 227: Day 3

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Editors Note:This week were at the 227th AAS Meeting in Kissimmee, FL. Along with several fellow authors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting at the end of each day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Welcome to Day 3 of the winter American Astronomical Society (AAS) meeting in Kissimmee! Several of us are attending the conference this year, and we will report highlights from each day here on astrobites. If youd like to see more timely updates during the day, we encourage you to follow @astrobites on twitter or search the #aas227 hashtag.Henry Norris Russell Lecture: Viewing the Universe with Infrared Eyes: The Spitzer Space Telescope (by Erika Nesvold)The Henry Norris Russell Award is the highest honor given by the AAS, for a lifetime of eminence in astronomy research. This years award went to Giovanni Fazio of the Harvard-Smithsonian Center for Astrophysics. Fazio became a leader in gamma ray astronomy before switching mid-career to the study of infrared astronomy, and he gave his award lecture on the latter subject, specifically on the Spitzer Space Telescope, one of the most successful infrared telescopes of all time.Artists rendering of the Spitzer space telescope. [NASA/JPL-Caltech]Spitzer has been operating for more than twelve years, and has resulted in over six thousand papers in refereed journals in that time. The telescope sits in an Earth-trailing orbit around the Sun, and is now farther from the Earth (1.4 AU) than the Earth is from the Sun. Fazio gave the audience a fascinating overview of the science done by Spitzer over more than a decade. One of the most productive areas of research for Spitzer is the study of exoplanets, which hadnt even been discovered when the Spitzer Telescope was first conceived. Spitzers high sensitivity and ability to observe exoplanets over

  11. AAS 228: Day 4

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Editors Note: Lastweek we were at the 228th AAS Meeting in San Diego, CA. Here is a final post aboutselectedevents on the last day of the meeting, written by authors fromastrobites.com, a grad-student collaborative project with which we recently announced a new partnership! Starting in July,keep an eye out for astrobites postsat AAS Nova in between Highlights(i.e., on Tuesdays and Thursdays).Were excited to be working together to bring you more recent astronomy research from AAS journals!Extrasolar Planets: Detection (by Leonardo dos Santos)Thursdays first session on exoplanets was about detecting these distant worlds, and the opening talk was given by Robert Siverd (Las Cumbres Observatory). He describes the NRES, a network of spectrographs that will look for exoplanets using the radial velocity method. One of the coolest aspects of this instrument is that it will feature an on the fly scheduling system that will perform observations as efficiently as possible. The spectrograph is still being tested, but a unit will be deployed at CTIO later this year.@lcogt contracted by @NASA_TESS for follow up of their candidates. #aas228 Jessie Christiansen (@aussiastronomer) June 16, 2016Measuring the depths of transits and eclipses in Spitzer has been problematic in the past, since the Spitzer instrument IRAC (InfraRed Array Camera) has a non-uniform response in its detectors pixels. But, as reported by James Ingalls (Spitzer Science Center, Caltech), observers are circumventing this issue by using what they call the staring mode (avoiding large pointing jumps) and an algorithm to pick sweet spot pixels. Moreover, the results from the IRAC Data Challenge are helping to better understand its behavior. Giuseppe Morello (University College London), on the other hand, explained how his research group gets rid of instrumental effects from IRAC using machine learning. This method removes systematics from exoplanet transit data no matter if the noise source is from an instrument or

  12. AAS 227: Day 4

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Editors Note:This week were at the 227th AAS Meeting in Kissimmee, FL. Along with several fellow authors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting at the end of each day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Welcome to Day 4 of the winter American Astronomical Society (AAS) meeting in Kissimmee! Several of us are attending the conference this year, and we will report highlights from each day here on astrobites. If youd like to see more timely updates during the day, we encourage you to follow @astrobites on twitter or search the #aas227 hashtag.Helen B. Warner Prize: Origins of Structure in Planetary Systems (by Erika Nesvold)Another excellent prize lecture started off todays sessions. The Helen B. Warner Prize is awarded for achievement in observational or theoretical astrophysics by a young researcher (no more than eight years after their Ph.D.). This years Warner Prize was presented to Ruth Murray-Clay of UC Santa Barbara. For her award lecture, Murray-Clay told us all about planetary system architecture: the number, masses, and orbits of planets in a given system.Ruth Murray-Clay [photo from http://web.physics.ucsb.edu/ ~murray/biocv.html]The underlying question motivating this type of research is: How rare is the Solar System? In other words, how likely is it that a given planetary system will have rocky planets close to their star, gas giants farther out, and ice giants at the outer reaches of the system? Answering this question will help us solve the physics problem of how and where planets form, and will also help us on our search for other planets like Earth.The data on exoplanet population from transit and radial velocity observations and from direct imaging tell us that our Solar System is not common (many systems we observe have much more eccentric gas giants), but that doesnt

  13. A.A., constructivism, and reflecting teams.

    PubMed

    Nevels, B

    1997-12-01

    Numerous studies and clinical anecdotes reveal a relationship between attendance at A.A. meetings and/or degree of involvement in A.A. and maintenance of sobriety. Hypotheses as to how A.A. and/or the A.A. meeting is helpful to its members have ranged from a focus on factors common to all therapy groups, to aspects of A.A. "treatment" which are behavioral in nature. Presented here is another way of understanding A.A.'s effectiveness within the frame of more recent, constructivistic approaches to family therapy. In particular, the A.A. topic meeting is compared to the reflecting team concept of Tom Anderson.

  14. Laboratory Astrophysics Division of The AAS (LAD)

    NASA Astrophysics Data System (ADS)

    Salama, Farid; Drake, R. P.; Federman, S. R.; Haxton, W. C.; Savin, D. W.

    2012-10-01

    The purpose of the Laboratory Astrophysics Division (LAD) is to advance our understanding of the Universe through the promotion of fundamental theoretical and experimental research into the underlying processes that drive the Cosmos. LAD represents all areas of astrophysics and planetary sciences. The first new AAS Division in more than 30 years, the LAD traces its history back to the recommendation from the scientific community via the White Paper from the 2006 NASA-sponsored Laboratory Astrophysics Workshop. This recommendation was endorsed by the Astronomy and Astrophysics Advisory Committee (AAAC), which advises the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), and the U.S. Department of Energy (DOE) on selected issues within the fields of astronomy and astrophysics that are of mutual interest and concern to the agencies. In January 2007, at the 209th AAS meeting, the AAS Council set up a Steering Committee to formulate Bylaws for a Working Group on Laboratory Astrophysics (WGLA). The AAS Council formally established the WGLA with a five-year mandate in May 2007, at the 210th AAS meeting. From 2008 through 2012, the WGLA annually sponsored Meetings in-a-Meeting at the AAS Summer Meetings. In May 2011, at the 218th AAS meeting, the AAS Council voted to convert the WGLA, at the end of its mandate, into a Division of the AAS and requested draft Bylaws from the Steering Committee. In January 2012, at the 219th AAS Meeting, the AAS Council formally approved the Bylaws and the creation of the LAD. The inaugural gathering and the first business meeting of the LAD were held at the 220th AAS meeting in Anchorage in June 2012. You can learn more about LAD by visiting its website at http://lad.aas.org/ and by subscribing to its mailing list.

  15. Laboratory Astrophysics Division of the AAS (LAD)

    NASA Technical Reports Server (NTRS)

    Salama, Farid; Drake, R. P.; Federman, S. R.; Haxton, W. C.; Savin, D. W.

    2012-01-01

    The purpose of the Laboratory Astrophysics Division (LAD) is to advance our understanding of the Universe through the promotion of fundamental theoretical and experimental research into the underlying processes that drive the Cosmos. LAD represents all areas of astrophysics and planetary sciences. The first new AAS Division in more than 30 years, the LAD traces its history back to the recommendation from the scientific community via the White Paper from the 2006 NASA-sponsored Laboratory Astrophysics Workshop. This recommendation was endorsed by the Astronomy and Astrophysics Advisory Committee (AAAC), which advises the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), and the U.S. Department of Energy (DOE) on selected issues within the fields of astronomy and astrophysics that are of mutual interest and concern to the agencies. In January 2007, at the 209th AAS meeting, the AAS Council set up a Steering Committee to formulate Bylaws for a Working Group on Laboratory Astrophysics (WGLA). The AAS Council formally established the WGLA with a five-year mandate in May 2007, at the 210th AAS meeting. From 2008 through 2012, the WGLA annually sponsored Meetings in-a-Meeting at the AAS Summer Meetings. In May 2011, at the 218th AAS meeting, the AAS Council voted to convert the WGLA, at the end of its mandate, into a Division of the AAS and requested draft Bylaws from the Steering Committee. In January 2012, at the 219th AAS Meeting, the AAS Council formally approved the Bylaws and the creation of the LAD. The inaugural gathering and the first business meeting of the LAD were held at the 220th AAS meeting in Anchorage in June 2012. You can learn more about LAD by visiting its website at http://lad.aas.org/ and by subscribing to its mailing list.

  16. Orbit of 1976 AA. [asteroid

    NASA Technical Reports Server (NTRS)

    Marsden, B. G.; Williams, J. G.

    1977-01-01

    The orbit of Asteroid 1976 AA is described, with attention given to calculations of its period and its distance from earth, both of which could be accurately and quickly determined by measuring the minor planet's position over wide ranges of hour angle on one to three nights. The geometry of the asteroid's orbit is compared to that of earth's orbit, and the periodicity of the minor planet's approaches to earth is projected. The motion of 1976 AA over an interval of seven centuries into both past and future is also studied; the possibility of its libration with respect to earth or to Venus is examined. Some data on closest approaches of the asteroid to Mars and Venus, as well as to earth, are given.

  17. Microstructural and Mechanical Characterization of a Dissimilar Friction Stir-Welded AA5083-AA7B04 Butt Joint

    NASA Astrophysics Data System (ADS)

    Chen, Yu; Ding, Hua; Cai, Zhihui; Zhao, Jingwei; Li, Jizhong

    2016-12-01

    Friction stir welding (FSW) has been used for joining AA5083 and AA7B04 alloy sheets with the aim of studying the microstructure and the mechanical properties of dissimilar FSW joints obtained by varying the initial base metal state of AA7B04 alloy. The results show that the initial base metal state has a significant impact on the material flow during dissimilar FSW. As compared with the joints placing hard alloy (artificially aged AA7B04-AA or naturally aged AA7B04-NA) on the retreating side, it becomes easier transporting AA5083 from advancing side to retreating side when soft alloy (annealed AA7B04-O) is placed on the retreating side. The atomic diffusion does not occur at the interface between AA5083 and AA7B04, indicating that the mixing of the two materials is merely mechanical. Grain refinement is observed in the stir zone. The failure location during tensile tests is different depending on the initial base metal state. The joints (AA5083/AA7B04-AA and AA5083/AA7B04-O) fail in the base metal on the soft material side which corresponds to the minimum values in hardness profiles. Differently, the joints (AA5083/AA5083 and AA5083/AA7B04-O) fail in the stir zone due to the presence of defects including "zigzag line," kissing bond and discontinuous voids.

  18. Microstructural and Mechanical Characterization of a Dissimilar Friction Stir-Welded AA5083-AA7B04 Butt Joint

    NASA Astrophysics Data System (ADS)

    Chen, Yu; Ding, Hua; Cai, Zhihui; Zhao, Jingwei; Li, Jizhong

    2017-02-01

    Friction stir welding (FSW) has been used for joining AA5083 and AA7B04 alloy sheets with the aim of studying the microstructure and the mechanical properties of dissimilar FSW joints obtained by varying the initial base metal state of AA7B04 alloy. The results show that the initial base metal state has a significant impact on the material flow during dissimilar FSW. As compared with the joints placing hard alloy (artificially aged AA7B04-AA or naturally aged AA7B04-NA) on the retreating side, it becomes easier transporting AA5083 from advancing side to retreating side when soft alloy (annealed AA7B04-O) is placed on the retreating side. The atomic diffusion does not occur at the interface between AA5083 and AA7B04, indicating that the mixing of the two materials is merely mechanical. Grain refinement is observed in the stir zone. The failure location during tensile tests is different depending on the initial base metal state. The joints (AA5083/AA7B04-AA and AA5083/AA7B04-O) fail in the base metal on the soft material side which corresponds to the minimum values in hardness profiles. Differently, the joints (AA5083/AA5083 and AA5083/AA7B04-O) fail in the stir zone due to the presence of defects including "zigzag line," kissing bond and discontinuous voids.

  19. Interface Formation During Fusion™ Casting of AA3003/AA4045 Aluminum Alloy Ingots

    NASA Astrophysics Data System (ADS)

    Di Ciano, Massimo; Caron, E. J. F. R.; Weckman, D. C.; Wells, M. A.

    2015-12-01

    Fusion™ casting is a unique Direct Chill continuous casting process whereby two different alloys can be cast simultaneously, producing a laminated ingot for rolling into clad sheet metal such as AA3003/AA4045 brazing sheet. Better understanding of the wetting and interface formation process during Fusion™ casting is required to further improve process yields and also explore use of other alloy systems for new applications. In this research, AA3003-core/AA4045-clad ingots were cast using a well-instrumented lab-scale Fusion™ casting system. As-cast Fusion™ interfaces were examined metallurgically and by mechanical testing. Computational fluid dynamic analyses of the FusionTM casts were also performed. It was shown that the liquid AA4045-clad alloy was able to successfully wet and create an oxide-free, metallurgical, and mechanically sound interface with the lightly oxidized AA3003-core shell material. Based on the results of this study, it is proposed that the bond formation process at the alloys interface during casting is a result of discrete penetration of AA4045 liquid at defects in the preexisting AA3003 oxide, dissolution of underlying AA3003 by liquid AA4045, and subsequent bridging between penetration sites. Spot exudation on the AA3003 chill cast surface due to remelting and inverse segregation may also improve the wetting and bonding process.

  20. AAS 228: Day 3 afternoon

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Editors Note:This week were at the 228th AAS Meeting in San Diego, CA. Along with a team ofauthors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting twiceeach day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Wikipedia Year of Science Editathon (by Meredith Rawls)Whats your first go-to source for an unfamiliar topic on the internet? If you said Wikipedia, youre not alone. For many people, Wikipedia is the primary source of information about astronomy and science. However, many Wikipedia articles about science topics are incomplete or missing, and women are underrepresented among scientists with biographies.To address this, the AAS Astronomy Education Board teamed up with the Wiki Education Foundation to host an edit-a-thon as part of the Wikipedia Year of Science. More than forty attendees spent the better part of three hours working through tutorials, creating new articles, and editing existing ones. The session was generously sponsored by the Simons Foundation.The Year of Science initiative seeks to bring Wikipedia editing skills to the classroom and help new editors find sustainable ways to contribute to Wikipedia in the long term. Anybody can create a free account and start editing!As a first-time Wikipedia contributor, I took the time to go through nearly all the tutorial exercises and familiarize myself with the process of editing a page. I decided to flesh out one section in an existing page about asteroseismology. Others created biography pages from scratch or selected various astronomical topics to write about. To me, the editing process felt like a cross between writing a blog post and a journal article, in a hack day type environment. Working through the tutorial and some examples renewed my empathy for learners who are tackling a new skill set for the first time. A full summary of our

  1. AAS 228: Day 1 morning

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Editors Note:This week were at the 228th AAS Meeting in San Diego, CA. Along with a team ofauthors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting twiceeach day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Come visit astrobites at the AAS booth we have swag!Things kicked off last night at our undergraduate reception booth. Thanks to all of you who stopped by we were delightedto hear from undergrads who already know and love the site, educators who want to use it in their classrooms, and students who had not yet been introduced to astrobites and were excited about a new resource!For the rest of the meeting we will be stationed at theAAS booth in the exhibit hall (booth #211-213), so drop by if you want to learn more (or pick up swag: weve got lots of stickers and sunglasses)!Mondaymorning was the official start of the meeting. Here are just a few of the talks and workshops astrobiters attended this morning.Opening Address(by Susanna Kohler)AAS President Meg Urry kicked off the meeting this morning at 8am with an overview of some of the great endeavors AAS is supporting. We astrobiters had personal motivation to drag ourselves out of bed that early: during this session, Urryannounced the new partnership between AAS and astrobites!Urry touched on some difficult topics in her welcome, including yesterdays tragedy in Orlando. Shereiteratedthe AASs support fortheCommittee for Sexual-Orientation and Gender Minorities in Astronomy (SGMA). She also reminded meeting attendees about the importance ofkeeping conference interactions professional, and pointed to the meetings anti-harassment policy.Partnership Announcement (by Michael Zevin)This morning, the American Astronomical Society announced the new partnership that it will have with Astrobites! We are beyond excited to embark on this new partnership with the

  2. AAS 228: Day 3 morning

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Editors Note:This week were at the 228th AAS Meeting in San Diego, CA. Along with a team ofauthors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting twiceeach day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Plenary Session 2015 Newton Lacy Pierce Prize Lecture: The Elephant in the Room: Effects of Distant, Massive Companions on Planetary System Architectures (by Leonardo dos Santos)The first session on Wednesday at 228th AAS Meeting was the Newton Lacy Pierce Prize Lecture by Heather Knutson (California Institute of Technology). This talk featured a broad range of research efforts on exoplanets, with the main focus on how we study the composition of their atmospheres, and how multi-body interactions carve the structure of the planetary systems we observe.One of her first points is the well-known idea that the Solar System is an oddball, compared to the exoplanet systems we have found so far: most of these systems contain hot Jupiters and mini-Neptunes at very close-in orbits around their host stars. Moreover, even when studying their transmission spectra, it is difficult to know the exact composition of their atmospheres.Knutson: it is difficult to constrain atmospheric composition of exoplanets (H-poor or H-rich+clouds?) #aas228pic.twitter.com/LdyN4o9RC7 astrobites (@astrobites) June 15, 2016The main proposal on how these systems formed is the migration scenario. In order to validate this idea, Dr. Knutson and her group The Friends of Hot Jupiters study systems with close-in gas giants and their frequency of binary companions, which are supposed to be the main culprits causing gas-giant migration. They found that approximately half of the observed systems have long-distance companions, providing strong validation of the migration scenario. Moreover, Dr. Knutson speculates that wide binaries have more

  3. AAS 228: Day 1 afternoon

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Editors Note:This week were at the 228th AAS Meeting in San Diego, CA. Along with a team ofauthors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting twiceeach day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Plenary Session: From Space Archeology to Serving the World Today: A 20-year Journey from the Jungles of Guatemala to a Network of Satellite Remote Sensing Facilities Around the World(by Michael Zevin)In the conferences second plenary session, NASAs Daniel Irwin turned the eyes of the conference back to Earth by highlighting the huge impact that NASA missions play in protecting and developing our own planet.Daniel Irwin: using satellite imagery to detect differences in vegetation and find ancient Mayan cities. #aas228 pic.twitter.com/9LFPQdCHTM astrobites (@astrobites) June 13, 2016Irwin came to be involved in NASA through his work mapping Guatemalan jungles, where he would spend 22 days at a time exploring the treacherous jungles on foot armed with a 1st generation GPS, a compass, and a machete. A colleague introduced Irwin to the satellite imagery thathe was exploring, demonstratinghow these images are a strong complement to field work. The sharing of this satellite data with nearby villages helped to show the encroachment of agriculture and the necessity of connecting space to the village. Satellite imagery also played a role in archeological endeavors, uncovering dozens of Mayan cities that have been buried for over a millennia by vegetation, and it provided evidence that the fall of the Mayan civilization may have been due to massive deforestation that ledto drought.Glacial retreat in Chile imaged by ISERV.Irwin displayed the constellation of NASAs Earth-monitoring satellites that have played an integral role in conserving our planet and alerting the world of natural disasters. He also showed

  4. 7 CFR 51.596 - U.S. Grade AA.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Consumer Standards for Celery Stalks Grades § 51.596 U.S. Grade AA. U.S. Grade AA shall consist of stalks of celery of similar varietal characteristics, which are well developed, and have good...

  5. 7 CFR 51.596 - U.S. Grade AA.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Consumer Standards for Celery Stalks Grades § 51.596 U.S. Grade AA. U.S. Grade AA shall consist of stalks of celery of similar varietal characteristics, which are well developed, and have good...

  6. 7 CFR 51.596 - U.S. Grade AA.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Consumer Standards for Celery Stalks Grades § 51.596 U.S. Grade AA. U.S. Grade AA shall consist of stalks of celery of similar varietal characteristics, which are...

  7. 7 CFR 51.596 - U.S. Grade AA.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Consumer Standards for Celery Stalks Grades § 51.596 U.S. Grade AA. U.S. Grade AA shall consist of stalks of celery of similar varietal characteristics, which are...

  8. The AAS: Its Next 100 Years

    NASA Astrophysics Data System (ADS)

    Wolff, S.

    1999-05-01

    The AAS: Its Next Hundred Years "We are probably nearing the limit of all we can know about astronomy."-- Simon Newcomb, 1888. The best way to celebrate the centennial of the AAS is to look forward, not backward, and to begin planning for the next 100 years. However, predicting the future is even more difficult than it was in Newcomb's time. We live in an era characterized by an unprecedented rate of change in the kinds of scientific questions we ask, the tools we use to answer them, and the way we communicate our results. This talk will highlight some of the issues that we will face as a community during the next 10--but not the next 100!--years and suggests that the AAS has a fundamental role to play in shaping the community response to these issues.

  9. Cytochrome aa3 in Haloferax volcanii

    PubMed Central

    Tanaka, Mikiei; Ogawa, Naohide; Ihara, Kunio; Sugiyama, Yasuo; Mukohata, Yasuo

    2002-01-01

    A cytochrome in an extremely halophilic archaeon, Haloferax volcanii, was purified to homogeneity. This protein displayed a redox difference spectrum that is characteristic of a-type cytochromes and a CN− complex spectrum that indicates the presence of heme a and heme a3. This cytochrome aa3 consisted of 44- and 35-kDa subunits. The amino acid sequence of the 44-kDa subunit was similar to that of the heme-copper oxidase subunit I, and critical amino acid residues for metal binding, such as histidines, were highly conserved. The reduced cytochrome c partially purified from the bacterial membrane fraction was oxidized by the cytochrome aa3, providing physiological evidence for electron transfer from cytochrome c to cytochrome aa3 in archaea. PMID:11790755

  10. AAS Nova and Astrobites: Making current astronomy research accessible

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna; Astrobites Team

    2016-10-01

    AAS Nova and Astrobites are two resources available for astronomers, astronomy students, and astronomy enthusiasts to keep up with some of the most recent research published across the field of astronomy. Both supported by the AAS, these two daily astrophysical literature blogs provide accessible summaries of recent publications on the arXiv and in AAS journals. We present the goals, content, and readership of AAS Nova and Astrobites, and discuss how they might be used as tools in the undergraduate classroom.

  11. 40 CFR Appendix A to Subpart Aa of... - Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart AA

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (40 CFR Part 63, Subpart A) to Subpart AA A Appendix A to Subpart AA of Part 63 Protection of... Hazardous Air Pollutants From Phosphoric Acid Manufacturing Plants Pt. 63, Subpt. AA, App. A Appendix A to Subpart AA of Part 63—Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart AA 40...

  12. 40 CFR Appendix A to Subpart Aa of... - Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart AA

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (40 CFR Part 63, Subpart A) to Subpart AA A Appendix A to Subpart AA of Part 63 Protection of... Hazardous Air Pollutants From Phosphoric Acid Manufacturing Plants Pt. 63, Subpt. AA, App. A Appendix A to Subpart AA of Part 63—Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart AA 40...

  13. AAS 228: Day 2 afternoon

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Editors Note:This week were at the 228th AAS Meeting in San Diego, CA. Along with a team ofauthors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting twiceeach day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.The Limits of Scientific Cosmology: Setting the Stage: Accepted Facts, and Testing Limitations in Theory and Data (by Gourav Khullar)With a stellar lineup of speakers to talk about current and future prospects of cosmology and its limits (or lack thereof), the first session kicked off with talks by Risa Wechsler, Joseph Silk, and Sean Carroll (his talk on Multiverses is described below, by Nathan Sanders). Risa set the stage with an elaborate description of the current accepted facts in the era of precision cosmology including the standard model of concordance cosmology, described by seven parameters and an accepted Lambda-CDM paradigm (with a cosmological constant and cold dark matter). The talk stressed on the fact that all these parameters are understood to a percent order precision, which is a remarkable deviation from the time in 1990s when according to Risa, Alan Guth never thought that any of these numbers could be measured precisely!Risa Wechsler describing our current constraints on what Dark Matter could constitute.Joseph Silk discussing limits on cosmological parameters.The CMB measurements, Big Bang Nucleosynthesis estimates and galaxy clustering statistics all contribute to locking down the description of our universe. She emphasized on the tensions between different probes to measure expansion rate H0 of the universe, and small scale predictions of cold dark matter simulations, but she is hopeful that these shall be resolved eventually. Joe Silk followed this up with his interpretation of trying to understand our place in the universe and placing limits on different parameters and

  14. Activity of vegetative insecticidal proteins Vip3Aa58 and Vip3Aa59 of Bacillus thuringiensis against lepidopteran pests.

    PubMed

    Baranek, Jakub; Kaznowski, Adam; Konecka, Edyta; Naimov, Samir

    2015-09-01

    Vegetative insecticidal proteins (Vips) secreted by some isolates of Bacillus thuringiensis show activity against insects and are regarded as insecticides against pests. A number of B. thuringiensis strains harbouring vip3A genes were isolated from different sources and identified by using a PCR based approach. The isolates with the highest insecticidal activity were indicated in screening tests, and their vip genes were cloned and sequenced. The analysis revealed two polymorphic Vip protein forms, which were classified as Vip3Aa58 and Vip3Aa59. After expression of the vip genes, the proteins were isolated and characterized. The activity of both toxins was estimated against economically important lepidopteran pests of woodlands (Dendrolimus pini), orchards (Cydia pomonella) and field crops (Spodoptera exigua). Vip3Aa58 and Vip3Aa59 were highly toxic and their potency surpassed those of many Cry proteins used in commercial bioinsecticides. Vip3Aa59 revealed similar larvicidal activity as Vip3Aa58 against S. exigua and C. pomonella. Despite 98% similarity of amino acid sequences of both proteins, Vip3Aa59 was significantly more active against D. pini. Additionally the effect of proteolytic activation of Vip58Aa and Vip3Aa59 on toxicity of D. pini and S. exigua was studied. Both Vip3Aa proteins did not show any activity against Tenebrio molitor (Coleoptera) larvae. The results suggest that the Vip3Aa58 and Vip3Aa59 toxins might be useful for controlling populations of insect pests of crops and forests.

  15. AAS 228: Day 2 morning

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-06-01

    Editors Note:This week were at the 228th AAS Meeting in San Diego, CA. Along with a team ofauthors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting twiceeach day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Plenary Session (Day 1) The Galaxy Zoo(by Benny Tsang)Galaxy Zoo was so hot that the servers hosting the galaxy images got melted down soon after being launched.Kevin Schawinski from ETH Zurich took us on a tour ofhis wonderful Galaxy Zoo. It is a huge zoo with about a quarter million zookeepers, they are citizen astronomers who collaboratively classify galaxies by their looks as an attempt to understand galaxy evolution. The big question that is being answered is: how do blue, actively star-forming galaxies evolve into red, quiescent (non-star-forming) galaxies? The Zoo helped reveal that blue galaxies turn into red galaxies via two possible paths galaxies might run out of supply of gas and shut off star formation slowly; or they could merge with one another and turn off star formation by destroying the gas reservoir rapidly!The Galaxy Zoo project also led to the discoveries of:Green Peas: they are the living fossils of galaxy evolution; compact, bright, green galaxies that are actively forming starsOverlapping galaxies: they are pairs of galaxies that are separated physically but happen to lie on the same line of sight; they provide excellent laboratories for studying dust extinctionHannys Voorwerp: an unusual object named after Hanny the discoverer, which is believed to be the first detection of quasar light echoThe idea of Galaxy Zoo in getting help from citizen scientists was further extended into an award-winningproject known as the Zooniverse, which is an online platform for streamlined crowd-sourcing for scientific research that requires human input. The future of astronomy is going to be

  16. Systemic AA amyloidosis: epidemiology, diagnosis, and management

    PubMed Central

    Real de Asúa, Diego; Costa, Ramón; Galván, Jose María; Filigheddu, María Teresa; Trujillo, Davinia; Cadiñanos, Julen

    2014-01-01

    The term “amyloidosis” encompasses the heterogeneous group of diseases caused by the extracellular deposition of autologous fibrillar proteins. The global incidence of amyloidosis is estimated at five to nine cases per million patient-years. While amyloid light-chain (AL) amyloidosis is more frequent in developed countries, amyloid A (AA) amyloidosis is more common in some European regions and in developing countries. The spectrum of AA amyloidosis has changed in recent decades owing to: an increase in the median age at diagnosis; a percent increase in the frequency of primary AL amyloidosis with respect to the AA type; and a substantial change in the epidemiology of the underlying diseases. Diagnosis of amyloidosis is based on clinical organ involvement and histological evidence of amyloid deposits. Among the many tinctorial characteristics of amyloid deposits, avidity for Congo red and metachromatic birefringence under unidirectional polarized light remain the gold standard. Once the initial diagnosis has been made, the amyloid subtype must be identified and systemic organ involvement evaluated. In this sense, the 123I-labeled serum amyloid P component scintigraphy is a safe and noninvasive technique that has revolutionized the diagnosis and monitoring of treatment in systemic amyloidosis. It can successfully identify anatomical patterns of amyloid deposition throughout the body and enables not only an initial estimation of prognosis, but also the monitoring of the course of the disease and the response to treatment. Given the etiologic diversity of AA amyloidosis, common therapeutic strategies are scarce. All treatment options should be based upon a greater control of the underlying disease, adequate organ support, and treatment of symptoms. Nevertheless, novel therapeutic strategies targeting the formation of amyloid fibrils and amyloid deposition may generate new expectations for patients with AA amyloidosis. PMID:25378951

  17. High cycle fatigue of AA6082 and AA6063 aluminum extrusions

    NASA Astrophysics Data System (ADS)

    Nanninga, Nicholas E.

    The high cycle fatigue behavior of hollow extruded AA6082 and AA6063 aluminum extrusions has been studied. Hollow extruded aluminum profiles can be processed into intricate shapes, and may be suitable replacements for fatigue critical automotive applications requiring reduced weight. There are several features inherent in hollow aluminum extrusions, such as seam welds, charge welds, microstructural variations and die lines. The effects of such extrusion variables on high cycle fatigue properties were studied by taking specimens from an actual car bumper extrusion. It appears that extrusion die lines create large anisotropy differences in fatigue properties, while welds themselves have little effect on fatigue lives. Removal of die lines greatly increased fatigue properties of AA6082 specimens taken transverse to the extrusion direction. Without die lines, anisotropy in fatigue properties between AA6082 specimens taken longitudinal and transverse to the extrusion direction, was significantly reduced, and properties associated with the orientation of the microstructure appears to be isotropic. A fibrous microstructure for AA6082 specimens showed great improvements in fatigue behavior. The effects of elevated temperatures and exposure of specimens to NaCl solutions was also studied. Exposure to the salt solution greatly reduced the fatigue lives of specimens, while elevated temperatures showed more moderate reductions in fatigue lives.

  18. Colchicine use in isolated renal AA amyloidosis.

    PubMed

    Meneses, Carlos F; Egües, César A; Uriarte, Miren; Belzunegui, Joaquín; Rezola, Marta

    2015-01-01

    We present the case of a 45-year-old woman, with two-year history of chronic renal insufficiency and proteinuria. A kidney biopsy showed the presence of AA amyloidosis (positive Congo red staining and immunohistochemistry). There was no evidence of amyloid deposits in other organs and there was no underlying disease. AA amyloidosis normally is secondary to chronic inflammatory or infectious diseases. High levels of IL-1, IL-6 and TNF-α play a role in the pathogenesis of amyloidosis and induce the synthesis of serum amyloid A protein (SAA), a precursor of tissue amyloid deposits. We empirically treated the patient with a low dose colchicine. The patient responded well. Colchicine has been used for the treatment of Familiar Mediterranean Fever and related auto-inflammatory diseases. To monitor treatment responses, we measured SAA finding low titers. Soon after treatment onset there were signs of improvement pertaining to proteinuria and stabilization of renal function.

  19. AAS Oral History Project - Seeking Planetary Scientist

    NASA Astrophysics Data System (ADS)

    Buxner, Sanlyn; Holbrook, Jarita

    2016-10-01

    Now in its fourth year, the AAS Oral History Project has interviewed over 100 space scientists from all over the world. Led by the AAS Historical Astronomy Division (HAD) and partially funded by the American Institute of Physics Niels Bohr Library and ongoing support from the AAS, volunteers have collected oral histories from space scientists at professional meetings starting in 2015, including AAS, DPS, and the IAU general assembly. Each interview lasts one and a half to two hours and focuses on interviewees' personal and professional lives. Questions include those about one's family, childhood, strong influences on one's scientific career, career path, successes and challenges, perspectives on how astronomy is changing as a field, and advice to the next generation. Each interview is audio recorded and transcribed, the content of which is checked with each interviewee. Once complete, interview transcripts are posted online as part of a larger oral history library at https://www.aip.org/history-programs/niels-bohr-library/oral-histories. We will present preliminary analysis of those interviewed including characterizing career status, age range, nationality, and primary field. Additionally, we will discuss trends beginning to emerge in analysis of participants' responses about data driven science and advice to the next generation. Future analysis will reveal a rich story of space scientists and will help the community address issues of diversity, controversies, and the changing landscape of science. We are actively recruiting individuals to be interviewed at this meeting from all stages of career from undergraduate students to retired and emeritus astronomers. We are especially interested in interviewing 40+E members of DPS. Contact Sanlyn Buxner to schedule an interview or to find out more information about the project (buxner@psi.edu). Contact Jarita Holbrook if you would like to become an interviewer for the project (astroholbrook@gmail.com).

  20. The Effectiveness of the AAS REU Program

    NASA Astrophysics Data System (ADS)

    Hemenway, M. K.; Boyce, P. B.; Milkey, R. W.

    1996-05-01

    In an attempt to address the particular needs of astronomy faculty and undergraduate students, in 1991 the Education Office of the American Astronomical Society approached the National Science Foundation with a unique proposal for funding through the Research Experiences for Undergraduates program. The goals of the AAS program were to "slow the hemorrhage of students out of science...", extend the REU program to non-NSF-funded scientists, to reach under-represented women and minority students particularly in small educational institutions, and to encourage research scientists there to mentor students. As this grant has now expired, the AAS has surveyed the 44 mentors and their students to assess the program's effect on the mentor and the mentor's career; the educational institution; and the student's education and career choices. More than half the mentors responded by the abstract deadline. The program clearly had an effect upon the individuals involved. The greatest effect (in 85% of the cases) was to develop more interest in the mentor's research project both among the students and among the mentor's faculty colleagues. The mentors rated the grant to be a medium or strong factor in their student's decision to pursue graduate study, which 90% of them did. All but one of the AAS-REU students attended an AAS meeting and 3/4 of those gave a paper on their project research. Over 90% of the mentors felt that the research experience strongly promoted a greater interest in science, a greater understanding of science and a desire to continue in science. According to the mentors, this was a very positive and beneficial program for the students as well as for themselves.

  1. Data Behind the Figures in AAS Journals

    NASA Astrophysics Data System (ADS)

    Biemesderfer, Chris

    2013-01-01

    Substantial amounts of digital data are produced in the scientific enterprise, and much of it is carefully analyzed and processed. Often resulting from a good deal of intellectual effort, many of these highly-processed products are published in the scholarly literature. Many of these data - or more precisely, representations of these data - are committed to the scholarly record in the forms of figures and tables that appear within articles: the AAS journals publish more than 30,000 figures and nearly 10,000 tables each year. For more than a decade, the AAS journals have accepted machine-readable tables that provide the data behind (some of) the tables, and recently the journals have started to encourage the submission of the data behind figures. (See the related poster by Greg Schwarz.) During this time, the journals have been refining techniques for acquiring and managing the digital data that underlie figures and tables. In 2012 the AAS was awarded a grant by the US NSF so that the journals can extend the methods for providing access to these data objects, through a deeper collaboration with the VO and with organizations like DataCite, and by spearheading discussions about the formats and metadata that will best facilitate long-term data management and access. An important component of these activities is educating scientists about the importance and benefits of making such data sets available.

  2. Introducing the AAS Astronomy Ambassadors Program

    NASA Astrophysics Data System (ADS)

    Gurton, S.; Fienberg, R. T.; Fraknoi, A.; Prather, E. E.

    2013-04-01

    Newly established by the American Astronomical Society (AAS), the Astronomy Ambassadors program is designed to support early-career AAS members with training in resources and techniques for effective outreach to students and/or the public. A pilot Astronomy Ambassadors workshop will be held at the January 2013 AAS meeting. Workshop participants will learn to communicate effectively with public and school audiences; find outreach opportunities and establish ongoing partnerships with local schools, science centers, museums, parks, and/or community centers; reach audiences with personal stories, hands-on activities, and jargon-free language; identify strategies and techniques to improve their presentation skills; gain access to a menu of outreach resources that work in a variety of settings; and become part of an active community of astronomers who do outreach. Applications are welcome from advanced undergraduates (those doing research and committed to continuing in astronomy), graduate students, and postdocs and new faculty in their first two years after receipt of the PhD. We especially encourage applications from members of groups that are presently underrepresented in science.

  3. AAS Publishing News: Astronomical Software Citation Workshop

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-07-01

    Do you write code for your research? Use astronomical software? Do you wish there were a better way of citing, sharing, archiving, or discovering software for astronomy research? You're not alone! In April 2015, AAS's publishing team joined other leaders in the astronomical software community in a meeting funded by the Sloan Foundation, with the purpose of discussing these issues and potential solutions. In attendance were representatives from academic astronomy, publishing, libraries, for-profit software sharing platforms, telescope facilities, and grantmaking institutions. The goal of the group was to establish “protocols, policies, and platforms for astronomical software citation, sharing, and archiving,” in the hopes of encouraging a set of normalized standards across the field. The AAS is now collaborating with leaders at GitHub to write grant proposals for a project to develop strategies for software discoverability and citation, in astronomy and beyond. If this topic interests you, you can find more details in this document released by the group after the meeting: http://astronomy-software-index.github.io/2015-workshop/ The group hopes to move this project forward with input and support from the broader community. Please share the above document, discuss it on social media using the hashtag #astroware (so that your conversations can be found!), or send private comments to julie.steffen@aas.org.

  4. Waldenström's macroglobulinemia associated with AA amyloidosis.

    PubMed

    Gardyn, J; Schwartz, A; Gal, R; Lewinski, U; Kristt, D; Cohen, A M

    2001-07-01

    It is widely accepted that amyloidosis in Waldenström's macroglobulinemia (WM) is exclusively due to amyloid light-chain deposition. However, only a small number of previous reports have actually characterized the type of amyloid in WM. We now report the third patient with WM and amyloid A protein (AA) amyloidosis. This patient developed malabsorption, nephrotic syndrome, and orthostatic hypotension. AA was immunohistochemically demonstrated in the rectal biopsy. In conjunction with previous examples of AA amyloidosis, the present report raises the possibility that AA amyloidosis may also occur in WM patients.

  5. Experimental immunologically mediated aplastic anemia (AA) in mice: cyclosporin A fails to protect against AA

    SciTech Connect

    Knospe, W.H.; Steinberg, D.; Gratwohl, A.; Speck, B.

    1984-07-01

    Immunologically mediated aplastic anemia (AA) in mice was induced by the i.v. injection of 10(7) lymph node cells (LNC) from H-2k identical but Mls mismatched CBA/J donor mice into previously irradiated (600 rad total body gamma) C3H/HeJ mice. Cyclosporin A (CsA), 25 mg/kg, was administered subcutaneously from day -1 to day 30. Control mice included C3H/HeJ mice which received 600 rad alone, C3H/HeJ mice which received 600 rad plus CsA as above, and C3H/HeJ mice which received 600 rad total body irradiation followed by 10(7) LNC from CBA/J donors. CsA failed to prevent lethal AA. These results suggest that the pathogenetic mechanisms operating in immunologically mediated AA differ from the mechanisms operating in rodents transplanted with allogeneically mismatched marrow or spleen cells which develop graft-versus-host disease. The results are consistent with a non-T cell-dependent mechanism causing the AA.

  6. Study on Fabrication of AA4032/AA6069 Cladding Billet Using Direct Chill Casting Process

    NASA Astrophysics Data System (ADS)

    Han, Xing; Zhang, Haitao; Shao, Bo; Li, Lei; Liu, Xuan; Cui, Jianzhong

    2016-04-01

    AA4032/AA6069 cladding billet in size of φ130 mm/φ110 mm was prepared by the modified direct chill casting process, and the parametric effect on casting performance was investigated using numerical simulation. Microstructures, elements distribution, and mechanical properties of the bonding interface were examined. The results show that metallurgical bonding interface can be obtained with the optimal parameters: the casting speed of 130 to 140 mm/min, the internal liquid level height of 50 to 60 mm, and the contact height of 40 to 50 mm. The metallurgical bonding interface is free of any discontinuities due to the fact that the alloying elements diffused across the interface and formed Ni-containing phase. Tensile strength of the cladding billet reaches 225.3 MPa, and the fracture position was located in AA6069 side, suggesting that the interface bonding strength is higher than the strength of AA6069. The interfacial shearing strength is 159.3 MPa, indicating excellent metallurgical bonding.

  7. AAS Special Session: Policy Making in Astronomy

    NASA Astrophysics Data System (ADS)

    Cardelli, J. A.; Massa, D.

    1995-12-01

    The professional astronomical community today is more diverse than at any time in its history. Individuals participating in creative research programs can be found in a wide range of positions. This type of diversity, which mixes research, education, and service (e.g. contract) work, represents the strength of contemporary astronomy. While recognizing the unavoidable reductions in funding and restructuring of organizations like NASA, it is imperative that the significance of the current diversity be considered during these processes. Creative ideas are one of the cornerstones of quality research, and they can originate anywhere. Consequently, it is essential that adequate research resources remain available for free and open competition by all astronomers. Our goal in this session is to bring together officials from the AAS, NASA, and the NSF to discuss how the policy and decision making process operates and whether it should be changed to better serve the general needs of the professional astronomical community. Examples of the issues we believe are important include: In establishing new policy, how can the needs of the average research astronomer be better addressed? How could input from such astronomers be provided to those who craft NASA/NSF policy? How can/should the AAS serve as an interface between policy/decision making bodies and its membership? Should the AAS membership become more actively/effectively involved in the decision making process and, if so, how? More information on this session and related issues can be found at the Association of Research Astronomers Home Page: http://www.phy.vill.edu/astro/faculty/ara/ara_home.htm

  8. Macroscopic anisotropy in AA5019A sheets

    SciTech Connect

    Choi, S.H.; Brem, J.C.; Barlat, F.; Oh, K.H.

    2000-05-11

    The macroscopic anisotropy for typical texture components in aluminum alloys and AA5019A sheet samples (H48 and O temper conditions) were investigated. In order to simultaneously consider the effects of morphological texture and crystallographic texture on macroscopic anisotropy, predictions of plastic properties were carried out using a full-constraints Taylor model and a visco-plastic self-consistent (VPSC) polycrystal model. The yield stress and r-value (width-to-thickness plastic strain ratio in uniaxial tension) anisotropy predicted using the VPSC model were in good agreement with experimental data.

  9. Swift Observations of SN 2007aa

    NASA Astrophysics Data System (ADS)

    Immler, S.; Brown, P. J.; Milne, P.

    2007-03-01

    Swift Ultraviolet/Optical Telescope (UVOT) and X-Ray Telescope (XRT) observed the type II SN 2007aa (CBET #850, IAUC #8814) on 2007-02-24.63 UT. The following UVOT magnitudes were measured: V = 15.8 (322 s exposure time), B = 16.4 (367 s), U = 16.9 (367 s), UVW1 [181-321nm] = 18.6 (737 s), UVM2 [166-268 nm] > 19.5 (3-sigma upper limit; 236 s), and UVW2 [112-264 nm] = 19.7 (725 s). The magnitudes have not been corrected for extinction.

  10. The cytochrome P450 2AA gene cluster in zebrafish (Danio rerio): Expression of CYP2AA1 and CYP2AA2 and response to phenobarbital-type inducers

    SciTech Connect

    Kubota, Akira; Bainy, Afonso C.D.; Woodin, Bruce R.; Goldstone, Jared V.; Stegeman, John J.

    2013-10-01

    The cytochrome P450 (CYP) 2 gene family is the largest and most diverse CYP gene family in vertebrates. In zebrafish, we have identified 10 genes in a new subfamily, CYP2AA, which does not show orthology to any human or other mammalian CYP genes. Here we report evolutionary and structural relationships of the 10 CYP2AA genes and expression of the first two genes, CYP2AA1 and CYP2AA2. Parsimony reconstruction of the tandem duplication pattern for the CYP2AA cluster suggests that CYP2AA1, CYP2AA2 and CYP2AA3 likely arose in the earlier duplication events and thus are most diverged in function from the other CYP2AAs. On the other hand, CYP2AA8 and CYP2AA9 are genes that arose in the latest duplication event, implying functional similarity between these two CYPs. A molecular model of CYP2AA1 showing the sequence conservation across the CYP2AA cluster reveals that the regions with the highest variability within the cluster map onto CYP2AA1 near the substrate access channels, suggesting differing substrate specificities. Zebrafish CYP2AA1 transcript was expressed predominantly in the intestine, while CYP2AA2 was most highly expressed in the kidney, suggesting differing roles in physiology. In the liver CYP2AA2 expression but not that of CYP2AA1, was increased by 1,4-bis [2-(3,5-dichloropyridyloxy)] benzene (TCPOBOP) and, to a lesser extent, by phenobarbital (PB). In contrast, pregnenolone 16α-carbonitrile (PCN) increased CYP2AA1 expression, but not CYP2AA2 in the liver. The results identify a CYP2 subfamily in zebrafish that includes genes apparently induced by PB-type chemicals and PXR agonists, the first concrete in vivo evidence for a PB-type response in fish. - Highlights: • A tandemly duplicated cluster of ten CYP2AA genes was described in zebrafish. • Parsimony and duplication analyses suggest pathways to CYP2AA diversity. • Homology models reveal amino acid positions possibly related to functional diversity. • The CYP2AA locus does not share synteny with

  11. Idiopathic systemic AA-amyloidosis in a skunk (Mephitis mephitis).

    PubMed

    Elhensheri, Mohamed; Linke, Reinhold P; Blankenburg, Anja; Beineke, Andreas

    2012-03-01

    This report describes a case of systemic amyloidosis in a captive striped skunk. At necropsy, bilateral alopecia, as well as reno-, hepato-, and splenomegaly were present. Congo red staining and immunohistochemistry revealed depositions of AA-amyloid in different organs. The lack of a predisposing disease is suggestive of idiopathic systemic AA-amyloidosis.

  12. Floor Plans: Section "AA", Section "BB"; Floor Framing Plans: Section ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Floor Plans: Section "A-A", Section "B-B"; Floor Framing Plans: Section "A-A", Section "B-B" - Fort Washington, Fort Washington Light, Northeast side of Potomac River at Fort Washington Park, Fort Washington, Prince George's County, MD

  13. Rational recovery: alternative to AA for addiction?

    PubMed

    Galanter, M; Egelko, S; Edwards, H

    1993-01-01

    Rational Recovery (RR) is a new self-help movement for substance abusers, with a cognitive orientation. It has been suggested as an alternative to Alcoholics Anonymous. This study was designed to examine the nature of RR and its impact on those who join. A national sample of 433 substance-abusing people attending 63 established RR groups was evaluated, using codable self-report questionnaires completed at RR meetings. Members were mostly men with college experience who had previously attended AA. Among recruits who attended their first RR meeting in the last month, 38% were abstinent in the last month. Among members who had joined 3 or more months before, 73% were abstinent in the last month; they had attended an average of 4.1 RR meetings in that month, and carried out exercises at home based on Rational Emotive Therapy. Among those who joined 6 or more months before, 58% reported at least 6 months of abstinence. Among members with a history of heavy cocaine use, the portion reporting abstinence in the last month was not significantly different from those who had never used cocaine. The minority of members who were engaged for 3 months were still drinking, though, and did so on an average of 9.9 days in the last month. RR succeeded in engaging substance abusers and promoting abstinence among many of them while presenting a cognitive orientation that is different from the spiritual one of AA. Its utility in substance abuse treatment warrants further assessment.

  14. States' Flexibility Waiver Plans for Alternate Assessments Based on Alternate Achievement Standards (AA-AAS). Synthesis Report 96

    ERIC Educational Resources Information Center

    Lazarus, Sheryl S.; Edwards, Lynn M.; Thurlow, Martha L.; Hodgson, Jennifer R.

    2014-01-01

    All states have alternate assessments based on alternate achievement standards (AA-AAS) for students with the most significant cognitive disabilities. For accountability purposes, the Elementary and Secondary Education Act (ESEA) allows up to 1% of students to be counted as proficient with this assessment option. In 2011 the U.S. Department of…

  15. Design and construction of a synthetic Bacillus thuringiensis Cry4Aa gene: hyperexpression in Escherichia coli.

    PubMed

    Hayakawa, Tohru; Howlader, Mohammad Tofazzal Hossain; Yamagiwa, Masashi; Sakai, Hiroshi

    2008-10-01

    Cry4Aa produced by Bacillus thuringiensis is a dipteran-specific toxin and is, therefore, of great interest for developing a bioinsecticide to control mosquitoes. However, the expression of Cry4Aa in Escherichia coli is relatively low, which is a major disadvantage in its development as a bioinsecticide. In this study, to establish an effective production system, a 1,914-bp modified gene (cry4Aa-S1) encoding Cry4Aa was designed and synthesized in accordance with the G + C content and codon preference of E. coli genes without altering the encoded amino acid sequence. The cry4Aa-S1 gene allowed a significant improvement in expression level, over five-fold, compared to that of the original cry4Aa gene. The product of the cry4Aa-S1 gene showed the same level of insecticidal activity against Culex pipiens larvae as that from cry4Aa. This suggested that unfavorable codon usage was one of the reasons for poor expression of cry4Aa in E. coli, and, therefore, changing the cry4Aa codons to accord with the codon usage in E. coli led to efficient production of Cry4Aa. Efficient production of Cry4Aa in E. coli can be a powerful measure to prepare a sufficient amount of Cry4Aa protein for both basic analytical and applied researches.

  16. Nephrotic Syndrome Associated with Lung Cancer: A Rare Case of Malignancy Associated with AA Amyloidosis.

    PubMed

    Gueutin, Victor; Langlois, Anne-Lyse; Shehwaro, Nathalie; Elharraqui, Ryme; Rouvier, Philippe; Izzedine, Hassane

    2013-01-01

    Nonhematologic malignancies are rarely reported to be associated with AA amyloidosis. Although the association between renal cell carcinoma and systemic AA amyloidosis has been established, the evidence linking pulmonary cancer to AA amyloidosis is scarce. Here, a case of biopsy-proven renal AA amyloidosis complicated with nephrotic syndrome associated with lung carcinoma is reported.

  17. Nephrotic Syndrome Associated with Lung Cancer: A Rare Case of Malignancy Associated with AA Amyloidosis

    PubMed Central

    Gueutin, Victor; Langlois, Anne-Lyse; Shehwaro, Nathalie; Elharraqui, Ryme; Rouvier, Philippe; Izzedine, Hassane

    2013-01-01

    Nonhematologic malignancies are rarely reported to be associated with AA amyloidosis. Although the association between renal cell carcinoma and systemic AA amyloidosis has been established, the evidence linking pulmonary cancer to AA amyloidosis is scarce. Here, a case of biopsy-proven renal AA amyloidosis complicated with nephrotic syndrome associated with lung carcinoma is reported. PMID:24558629

  18. Hot stamping of AA7075 aluminum sheets

    NASA Astrophysics Data System (ADS)

    Mendiguren, J.; Saenz de Argandona, E.; Galdos, L.

    2016-11-01

    In this work the formability of a high strength aluminium alloy (AA7075-T6) for the stamping of an automotive component has been studied. Due to the low formability of the selected alloy, two different heat assisted forming strategies have been analysed. On the one hand, the W-temper process, where the thermal process is carried out prior to the forming operation. On the other hand, the hot stamping process, where the thermal process is carried out at the same time as the forming. The results showed that both technology were able to form the component avoiding any failure of the material. On the contrary, both processes reduced the final mechanical properties of the material compared to the as received material condition. However, the obtained mechanical properties doubled the strength of commonly used 5xxx and 6xxx aluminium alloys.

  19. A&A Painting and Restoration Co., Inc. Information Sheet

    EPA Pesticide Factsheets

    A&A Painting and Restoration Co., Inc. (the Company) is located in Great Mills, Maryland. The settlement involves renovation activities conducted at properties constructed prior to 1978, located in Drayden, Maryland.

  20. 40 CFR Table Aa-2 to Subpart Aa of... - Kraft Lime Kiln and Calciner Emissions Factors for CH4 and N2O

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Kraft Lime Kiln and Calciner Emissions... Manufacturing Pt. 98, Subpt. AA, Table AA -2 Table AA-2 to Subpart AA of Part 98—Kraft Lime Kiln and Calciner... CH4 N2O Kraft calciners CH4 N2O Residual Oil (any type) 0.0027 0 0.0027 0.0003 Distillate Oil...

  1. Section AA through main entrance gates & west stairs. San ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Section AA through main entrance gates & west stairs. San Bernardino Valley Union Junior College, Science Building. Also includes plans and sections of boys' and girls' toilets. Howard E. Jones, Architect, San Bernardino, California. Sheet 5, job no. 311. Scales 1/4 inch to the foot (section AA) and 1/2 inch to the foot (toilet rooms). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  2. Fecal transmission of AA amyloidosis in the cheetah contributes to high incidence of disease.

    PubMed

    Zhang, Beiru; Une, Yumi; Fu, Xiaoying; Yan, Jingmin; Ge, FengXia; Yao, Junjie; Sawashita, Jinko; Mori, Masayuki; Tomozawa, Hiroshi; Kametani, Fuyuki; Higuchi, Keiichi

    2008-05-20

    AA amyloidosis is one of the principal causes of morbidity and mortality in captive cheetahs (Acinonyx jubatus), which are in danger of extinction, but little is known about the underlying mechanisms. Given the transmissible characteristics of AA amyloidosis, transmission between captive cheetahs may be a possible mechanism involved in the high incidence of AA amyloidosis. In this study of animals with AA amyloidosis, we found that cheetah feces contained AA amyloid fibrils that were different from those of the liver with regard to molecular weight and shape and had greater transmissibility. The infectious activity of fecal AA amyloid fibrils was reduced or abolished by the protein denaturants 6 M guanidine.HCl and formic acid or by AA immunodepletion. Thus, we propose that feces are a vehicle of transmission that may accelerate AA amyloidosis in captive cheetah populations. These results provide a pathogenesis for AA amyloidosis and suggest possible measures for rescuing cheetahs from extinction.

  3. Characterization of the radical-scavenging reaction of 2-O-substituted ascorbic acid derivatives, AA-2G, AA-2P, and AA-2S: a kinetic and stoichiometric study.

    PubMed

    Takebayashi, Jun; Tai, Akihiro; Gohda, Eiichi; Yamamoto, Itaru

    2006-04-01

    The aim of this study was to characterize the antioxidant activity of three ascorbic acid (AA) derivatives O-substituted at the C-2 position of AA: ascorbic acid 2-glucoside (AA-2G), ascorbic acid 2-phosphate (AA-2P), and ascorbic acid 2-sulfate (AA-2S). The radical-scavenging activities of these AA derivatives and some common low molecular-weight antioxidants such as uric acid or glutathione against 1,1-diphenyl-picrylhydrazyl (DPPH) radical, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS+), or galvinoxyl radical were kinetically and stoichiometrically evaluated under pH-controlled conditions. Those AA derivatives slowly and continuously reacted with DPPH radical and ABTS+, but not with galvinoxyl radical. They effectively reacted with DPPH radical under acidic conditions and with ABTS+ under neutral conditions. In contrast, AA immediately quenched all species of radicals tested at all pH values investigated. The reactivity of Trolox, a water-soluble vitamin E analogue, was comparable to that of AA in terms of kinetics and stoichiometrics. Uric acid and glutathione exhibited long-lasting radical-scavenging activity against these radicals under certain pH conditions. The radical-scavenging profiles of AA derivatives were closer to those of uric acid and glutathione rather than to that of AA. The number of radicals scavenged by one molecule of AA derivatives, uric acid, or glutathione was equal to or greater than that by AA or Trolox under the appropriate conditions. These data suggest the potential usage of AA derivatives as radical scavengers.

  4. Recrystallization behaviour of AA6063 extrusions

    NASA Astrophysics Data System (ADS)

    Zhang, K.; Pettersen, T.; Paulsen, C. O.; Marthinsen, K.; Holmedal, B.; Segatori, A.

    2015-08-01

    Cylindrical profiles of an AA6063 aluminium alloy were produced in a lab-scale direct extrusion set-up. The extrusion was performed at 300 °C, 450 °C and 550 °C, respectively, with the same ram speed. Immediate water quenching was applied to the profiles and the end of billet (butt-end) after extrusion. Microstructure and texture of the material in different states were measured by electron back-scattered diffraction. Only the profile extruded at 300 °C, was found in the deformed state after extrusion, featuring a fibrous grain structure and a strong <111> and weak <100> double fibre texture. Post-extrusion annealing of this profile at 450 °C resulted in an almost fully recrystallized structure (recrystallized fraction of 87%) and with a texture similar to that of the as-deformed state. The profile extruded at 450 °C was almost fully recrystallized (recrystallization fraction 91%) already after quenching, and with a texture characterized by a weak <111> and strong <100> double fibre. The profile extruded at 550 °C showed a partially recrystallized grain structure with recrystallization fraction of 71%, and with a texture dominated by a <100> fibre. The influence of the deformation conditions on the recrystallization behaviour, in terms of recrystallization kinetics and mechanisms, are discussed in view of these results.

  5. Observations of AA Tau requested to schedule XMM-Newton

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2013-08-01

    Dr. Hans Moritz Guenther (Harvard-Smithsonian Center for Astrophysics) has requested nightly observations of the classical T Tauri star AA Tau in order to schedule x-ray observations with XMM-Newton that have been planned for between 2013 August 15 and September 15. The purpose of the AAVSO observations is to determine whether AA Tau is at a suitable magnitude for the satellite observations. Taurus is difficult to observe during this time period but that is exactly why AAVSO assistance is needed! AA Tau is a morning object, and also, many of the professional ground-based telescopes are offline because of the US southwest monsoon season. Since it is critical to know the brightness of AA Tau, AAVSO observations will be truly essential. Nightly visual and snapshot (not more than once per night) observations beginning now and continuing through September 20 are needed. Coverage beginning ahead of the XMM window is requested because there is a one- to two-week lead time for the target to be inserted into the telescope schedule. Continuing the nightly observations a few days beyond the end of the XMM window will give better optical context for the x-ray data. AA Tau ranges between ~12.8V and ~16.1V; since December 2011 or earlier it has been at ~14.5V. The most recent observation in the AAVSO International Database shows it at 14.779V on 2013 Feb 5 (J. Roe, Bourbon, MO). Dr. Guenther writes, "AA Tau is surrounded by a thick accretion disk which is seen nearly edge-on. For decades the light curve of AA Tau showed regular eclipsing events when the accretion funnel rotated through the line of sight. However, earlier this year J. Bouvier and his group found that this behavior changed dramatically: AA Tau now seems to be deeply absorbed all the time (V band 14.5 mag). In collaboration with this group we will perform X-ray observations of AA Tau with the XMM-Newton satellite." Finder charts with sequence may be created using the AAVSO Variable Star Plo! tter (http

  6. The 9aaTAD Transactivation Domains: From Gal4 to p53

    PubMed Central

    Havelka, Marek; Rezacova, Martina

    2016-01-01

    The family of the Nine amino acid Transactivation Domain, 9aaTAD family, comprises currently over 40 members. The 9aaTAD domains are universally recognized by the transcriptional machinery from yeast to man. We had identified the 9aaTAD domains in the p53, Msn2, Pdr1 and B42 activators by our prediction algorithm. In this study, their competence to activate transcription as small peptides was proven. Not surprisingly, we elicited immense 9aaTAD divergence in hundreds of identified orthologs and numerous examples of the 9aaTAD species' convergence. We found unforeseen similarity of the mammalian p53 with yeast Gal4 9aaTAD domains. Furthermore, we identified artificial 9aaTAD domains generated accidentally by others. From an evolutionary perspective, the observed easiness to generate 9aaTAD transactivation domains indicates the natural advantage for spontaneous generation of transcription factors from DNA binding precursors. PMID:27618436

  7. Introducing structured abstracts for A&A articles

    NASA Astrophysics Data System (ADS)

    Bertout, Claude; Schneider, Peter

    2005-10-01

    Context: Due to their wide availability, abstracts have become the most important part of any astrophysical paper. Aims: Having noticed that abstracts published in astronomical journals are not always optimal, we introduce the concept of structured abstracts for A&A articles. Methods: We explain what structured abstracts are and where they come from, provide examples showing how to structure an abstract, and discuss the advantages and drawbacks of this novel concept. In an on-line appendix, we show what some published abstracts look like once they are structured. Results: We demonstrate the improvements in information content, readability, and style that can be made when writing structured abstracts instead of traditional ones. Conclusions: A new version 6.0 of the A&A LaTeX macro is now available for structuring the abstracts of articles, and A&A authors are kindly invited to use it for their new submissions.

  8. Outcomes From AAS Hack Day at the 227th AAS Meeting

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Editors Note:This is a final post from the 227th AAS Meeting in Kissimmee, FL. This special summary of AAS Hack Day, a meeting of AAS members to collaboratively work on various small projects, was written by Meredith Rawls (@Merrdiff) and was originally posted on astrobites.com.As the 227thAmerican Astronomical Society meeting drew to a close (see highlights from Day 1, Day 2, Day 3, and Day 4), a group of at least 50 attendees spent Day 4working on small projects fondly called hacks. Thanks to sponsorship from LSST and Northrup Grumman, the industrious hackers werewell-caffeinated and fed so we could devote time and energy toworking in groups on one-day projects.TheHack Day beganat 10am with pitches. Anybody with a project idea was welcome to briefly speak and try to convince others to work with them. Only someideas panned out, but the enthusiasm was palpable. Its not every day you get a full room of astronomers and affiliates eager to spend hours working on fun and useful projects to benefit the community.#hackAAS is getting underway! #aas227 pic.twitter.com/yX7jlOnSCK James R A Davenport (@jradavenport) January 8, 2016Here is a rundown of what we accomplished. Pretty impressive for a single day! Many thanks to fellow astrobiter Erika Nesvold (now at Carnegie DTM; @erikanesvold) whose hack was live-documenting all the other hacks. Her tweets as @astrobites appeared with the #hackaas hashtag, and her notes made this recap post infinitely easier to write.Interested in joining the fun? Sign up for Hack Day at the 2017 JanuaryAAS meeting (its free with meeting registration), and consider applying for the .Astronomy conference this summer.Towards Optimal Session Scheduling:Adrian Price-Whelan (Columbia), David Hogg (NYU), and Scott Idem (AAS) began writing a program to take all submitted abstracts to a conference like AAS and sort them using keywords to avoid scheduling similar talks in parallel sessions. Its impossible to make everyone happy, but minimizing conflicts

  9. Wear Behaviour of Carbon Nanotubes Reinforced Nanocrystalline AA 4032 Composites

    NASA Astrophysics Data System (ADS)

    Senthil Saravanari, M. S.; Kumaresh Babu, S. P.; Sivaprasad, K.

    2016-09-01

    The present paper emphasizes the friction and wear properties of Carbon Nanotubes reinforced AA 4032 nanocomposites prepared by powder metallurgy technique. CNTs are multi-wall in nature and prepared by electric arc discharge method. Multi-walled CNTs are blended with AA 4032 elemental powders and compaction followed by sintering to get bulk nanocomposites. The strength of the composites has been evaluated by microhardness and the surface contact between the nanocomposites and EN 32 steel has been evaluated by Pin on disk tester. The results are proven that reinforcement of CNTs play a major role in the enhancement of hardness and wear.

  10. Characterization of amyloid in equine recurrent uveitis as AA amyloid.

    PubMed

    Ostevik, L; de Souza, G A; Wien, T N; Gunnes, G; Sørby, R

    2014-01-01

    Two horses with chronic uveitis and histological lesions consistent with equine recurrent uveitis (ERU) were examined. Microscopical findings in the ciliary body included deposits of amyloid lining the non-pigmented epithelium, intracytoplasmic, rod-shaped, eosinophilic inclusions and intraepithelial infiltration of T lymphocytes. Ultrastructural examination of the ciliary body of one horse confirmed the presence of abundant extracellular deposits of non-branching fibrils (9-11 nm in diameter) consistent with amyloid. Immunohistochemistry revealed strong positive labelling for AA amyloid and mass spectrometry showed the amyloid to consist primarily of serum amyloid A1 in both cases. The findings suggest that localized, intraocular AA amyloidosis may occur in horses with ERU.

  11. An Existential Approach: An Alternative to the AA Model of Recovery

    ERIC Educational Resources Information Center

    Rogers, Maria A.; Cobia, Debra

    2008-01-01

    Alcoholics Anonymous (AA) is the most widely used organization for the treatment of alcoholism. AA's philosophy has changed how many people view themselves and their substance use. The majority of substance abuse programs in the United States use the 12 steps, either by making them the basis of their treatment program, or by introducing AA to…

  12. Displaying Now-Understanding: The Finnish Change-of-State Token "aa"

    ERIC Educational Resources Information Center

    Koivisto, Aino

    2015-01-01

    This article discusses the use of the Finnish change-of-state token "aa" that has previously not been identified. The central claim is that even though "aa" indicates a cognitive shift experienced by the speaker, it does not function as a receipt of new information. Instead, the token "aa" indicates that the speaker…

  13. An Analysis of the Rise and Fall of the AA-MAS Policy

    ERIC Educational Resources Information Center

    Lazarus, Sheryl S.; Thurlow, Martha L.; Ysseldyke, James E.; Edwards, Lynn M.

    2015-01-01

    In 2005, to address concerns about students who might fall in the "gap" between the regular assessment and the alternate assessment based on alternate achievement standards (AA-AAS), the U.S. Department of Education announced that states could develop alternate assessments based on modified achievement standards (AA-MAS). This article…

  14. [Expression of mosquitocidal Cyt1Aa toxin from Bacillus thuringiensis subsp. israelensis in Asticcacaulis excentricus].

    PubMed

    Zheng, Da-sheng; Crickmore, Neil; Cai, Ya-jun; Yan, Jian-ping; Yuan, Zhi-ming

    2007-04-01

    Asticcacaulis excentricus, who lives in upper-layer waters providing food resource to the mosquito larvae and has been proven to be a successful host to produce the mosquitocidal binary toxins or Cry11Aa toxin from Bacilli (Liu et al., 1996, Nat Biotech 14: 343; Armengol, et al. , 2005, Curr Microbiol 51: 430), was developed to express cyt1Aa gene from Bacillus thuringiensis subsp. israelensis (Bti). Two A. excentricus transformants were constructed with the attempt of producing CytlAa alone and alongside with Cry11Aa, repectively. Detection of expressed Cry11Aa and CytlAa proteins by immunoblot in the recombinant A. excentricus clones showed that either cry11Aa or cyt1Aa was expressed well solely but not simultaneously although both restriction analyses of plasmid DNA and DNA sequencing showed that the transformed plasmid was identical to scheme. To investigate the reason why the recombinant A. excentricus harboring both genes and their ribosome binding site (RBS) sequences expressed only Cry11Aa, the total RNA of A. excentricus cells was extracted and revealed three-band pattern in which all RNA molecule weights are not greater than 16S RNA of Escherichia coli by formamide agarose gel electrophoresis, indicating that different RNA systems within these two Gram-negative strains required distinguishingly organised constructs to express multiple foreign genes. It is hypothesized that an extra promoter upstream of RBS sequence is required to express cyt1Aa in the cry11Aa-cyt1Aa tandom plasmid.

  15. 49 CFR 178.56 - Specification 4AA480 welded steel cylinders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Specification 4AA480 welded steel cylinders. 178... FOR PACKAGINGS Specifications for Cylinders § 178.56 Specification 4AA480 welded steel cylinders. (a) Type, size, and service pressure. A DOT 4AA480 cylinder is a welded steel cylinder having a...

  16. 49 CFR 178.37 - Specification 3AA and 3AAX seamless steel cylinders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Specification 3AA and 3AAX seamless steel...) SPECIFICATIONS FOR PACKAGINGS Specifications for Cylinders § 178.37 Specification 3AA and 3AAX seamless steel... conform to the following: (1) A DOT-3AA cylinder is a seamless steel cylinder with a water...

  17. 49 CFR 178.56 - Specification 4AA480 welded steel cylinders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Specification 4AA480 welded steel cylinders. 178... FOR PACKAGINGS Specifications for Cylinders § 178.56 Specification 4AA480 welded steel cylinders. (a) Type, size, and service pressure. A DOT 4AA480 cylinder is a welded steel cylinder having a...

  18. 49 CFR 178.37 - Specification 3AA and 3AAX seamless steel cylinders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Specification 3AA and 3AAX seamless steel...) SPECIFICATIONS FOR PACKAGINGS Specifications for Cylinders § 178.37 Specification 3AA and 3AAX seamless steel... conform to the following: (1) A DOT-3AA cylinder is a seamless steel cylinder with a water...

  19. 49 CFR 178.56 - Specification 4AA480 welded steel cylinders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Specification 4AA480 welded steel cylinders. 178... FOR PACKAGINGS Specifications for Cylinders § 178.56 Specification 4AA480 welded steel cylinders. (a) Type, size, and service pressure. A DOT 4AA480 cylinder is a welded steel cylinder having a...

  20. 49 CFR 178.56 - Specification 4AA480 welded steel cylinders.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Specification 4AA480 welded steel cylinders. 178... FOR PACKAGINGS Specifications for Cylinders § 178.56 Specification 4AA480 welded steel cylinders. (a) Type, size, and service pressure. A DOT 4AA480 cylinder is a welded steel cylinder having a...

  1. 49 CFR 178.37 - Specification 3AA and 3AAX seamless steel cylinders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Specification 3AA and 3AAX seamless steel...) SPECIFICATIONS FOR PACKAGINGS Specifications for Cylinders § 178.37 Specification 3AA and 3AAX seamless steel... conform to the following: (1) A DOT-3AA cylinder is a seamless steel cylinder with a water...

  2. DEVELOPMENTAL AND WITHDRAWAL EFFECTS OF ADOLESCENT AAS EXPOSURE ON THE GLUTAMATERGIC SYSTEM IN HAMSTERS

    PubMed Central

    Carrillo, Maria; Ricci, Lesley A.; Melloni, Richard H.

    2011-01-01

    In the Syrian hamster (Mesocricetus auratus) glutamate activity has been implicated in the modulation of adolescent anabolic-androgenic steroid (AAS)-induced aggression. The current study investigated the time course of adolescent AAS-induced neurodevelopmental and withdrawal effects on the glutamatergic system and examined whether these changes paralleled those of adolescent AAS-induced aggression. Glutamate activity in brain areas comprising the aggression circuit in hamsters and aggression were examined following 1, 2, 3 and 4 weeks of AAS treatment or 1, 2, 3 and 4 weeks following the cessation of AAS exposure. In these studies glutamate activity was examined using vesicular glutamate transporter 2 (VGLUT2). The onset of aggression was observed following 2 weeks exposure to AAS and continued to increase showing maximal aggression levels after 4 weeks of AAS treatment. This aggressive phenotype was detected after 2 weeks of withdrawal from AAS. The time-course of AAS-induced changes in latero anterior hypothalamus (LAH)-VGLUT2 closely paralleled increases in aggression. Increases in LAH-VGLUT2 were first detected in animals exposed to AAS for 2 weeks and were maintained up to 3 weeks following the cessation of AAS treatment. AAS treatment also produced developmental and long-term alterations in VGLUT2 expression within other aggression areas. However, AAS-induced changes in glutamate activity within these regions did not coincide with changes in aggression. Together, these data indicate that adolescent AAS treatment leads to alterations in the glutamatergic system in brain areas implicated in aggression control, yet only alterations in LAH-glutamate parallel the time course of AAS-induced changes in the aggressive phenotype. PMID:21500881

  3. Developmental and withdrawal effects of adolescent AAS exposure on the glutamatergic system in hamsters.

    PubMed

    Carrillo, Maria; Ricci, Lesley A; Melloni, Richard H

    2011-06-01

    In the Syrian hamster (Mesocricetus auratus) glutamate activity has been implicated in the modulation of adolescent anabolic-androgenic steroid (AAS)-induced aggression. The current study investigated the time course of adolescent AAS-induced neurodevelopmental and withdrawal effects on the glutamatergic system and examined whether these changes paralleled those of adolescent AAS-induced aggression. Glutamate activity in brain areas comprising the aggression circuit in hamsters and aggression levels were examined following 1, 2, 3, and 4 weeks of AAS treatment or 1, 2, 3, and 4 weeks following the cessation of AAS exposure. In these studies glutamate activity was examined using vesicular glutamate transporter 2 (VGLUT2). The onset of aggression was observed following 2 weeks exposure to AAS and continued to increase showing maximal aggression levels after 4 weeks of AAS treatment. This aggressive phenotype was detected after 2 weeks of withdrawal from AAS. The time-course of AAS-induced changes in latero-anterior hypothalamus (LAH)-VGLUT2 closely paralleled increases in aggression. Increases in LAH-VGLUT2 were first detected in animals exposed to AAS for 2 weeks and were maintained up to 3 weeks following the cessation of AAS treatment. AAS treatment also produced developmental and long-term alterations in VGLUT2 expression within other aggression areas. However, AAS-induced changes in glutamate activity within these regions did not coincide with changes in aggression. Together, these data indicate that adolescent AAS treatment leads to alterations in the glutamatergic system in brain areas implicated in aggression control, yet only alterations in LAH-glutamate parallel the time course of AAS-induced changes in the aggressive phenotype.

  4. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  5. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  6. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  7. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  8. Controlling Works, Section AA at Bear Trap Dam, Section BB ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Controlling Works, Section A-A at Bear Trap Dam, Section B-B at Bear-Trap Dam, Section C-C at Sluice Gate - Chicago Sanitary and Ship Canal, Lockport Controlling Works, Illinois Waterway River Mile 293.2, Lockport, Will County, IL

  9. 32. SECTIONS AA, BB, CC, DD, AND EE WASTE CALCINATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. SECTIONS A-A, B-B, C-C, D-D, AND E-E WASTE CALCINATION FACILITY SHOWING RELATIONSHIPS OF DIFFERENT FLOOR LEVELS TO ONE ANOTHER. INEEL DRAWING NUMBER 200-0633-00-287-106353. FLUOR NUMBER 5775-CPP-633-A-3. - Idaho National Engineering Laboratory, Old Waste Calcining Facility, Scoville, Butte County, ID

  10. Structural proteins of the Actinobacillus actinomycetemcomitans bacteriophage phi Aa.

    PubMed

    Stevens, R H; Hammond, B F; Fine, D H

    1990-08-01

    øAa is an A1 morphotype bacteriophage which infects certain strains of Actinobacillus actinomycetemcomitans. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of dissociated, purified phi Aa particles revealed 7 major structural proteins (P1-P7) ranging in size from 17.5 to 52.7 kilodaltons (Kd). Treatment of the intact phage particles with 67% dimethyl sulfoxide (DMSO) resulted in the separation of the virion head and tail subunits. Purification of the head subunits was accomplished by sucrose density gradient centrifugation of the DMSO-treated phage particles. The purified head subunits were composed of a single protein having an electrophoretic mobility which corresponded to a 39.5 Kd protein (P3) of the intact virus. Raising the pH of a purified phi Aa suspension to 12.7 disrupted the head subunits, as well as the tail tube and tail fibers, releasing intact contractile tail sheaths. The tail sheaths were collected by centrifugation. The purified tail sheaths were analyzed by SDS-PAGE and were found to be composed of two proteins (P1 and P2) having molecular weights of 52.7 and 41.2 Kd respectively. The location of each of the 4 remaining major structural proteins in the phi Aa virion remains to be determined.

  11. Fatigue properties of as-welded AA6005 and AA6082 aluminium alloys in T1 and T5 temper condition

    SciTech Connect

    Ranes, M.; Kluken, A.O.; Midling, O.T.

    1996-12-31

    The present investigation was undertaken to determine the as-welded fatigue properties of AA6005 and AA6082 aluminium alloys in the T1 and T5 temper conditions. Extruded flat bars of the base materials were welded by means of the Metal Inert Gas (MIG), Friction Stir and Plasma-keyhole techniques. The latter technique was only employed for alloy AA6005. The weldments were subsequently fatigue tested at a load ratio of 0.5. The results revealed that the friction stir welds had fatigue properties superior to both the MIG and Plasma-keyhole welds. For alloy AA6005 the fatigue properties of the friction stir weld was close to the base material properties. The shortest fatigue life was exhibited by the MIG welds. The fatigue strength of these weldments appear to be affected by the base metal temper condition. For this reason, MIG welds on alloy AA6082 should be performed in the T5 temper condition, while alloy AA6005 should be welded in the T1 temper condition. Plasma-keyhole welds should be performed on T1 tempered material rather than on T5 tempered material. Repair welding of MIG welds on the T1 tempered base material resulted in improved fatigue properties of AA6082 weldments, while the fatigue strength of AA6005 weldments remained unaffected. The fatigue properties of MIG welds in alloy AA6082 correspond well with the static strength properties.

  12. Core-corona PSt/P(BA-AA) composite particles by two-stage emulsion polymerization

    NASA Astrophysics Data System (ADS)

    Xie, Delong; Ren, Xiaolin; Zhang, Xinya; Liao, Shijun

    2016-03-01

    Raspberry-shaped composite particles with polystyrene (PSt) as core and poly(n-butyl acrylate-co-acrylic acid) (P(BA-AA)) as corona were synthesized via emulsion polymerization. The random copolymer, P(BA-AA), was pre-prepared and used as a polymeric surfactant, its emulsifying properties adjusted by changing the mass ratio of BA and AA. The morphology of the resulting core-corona composite particles, P(St/P(BA-AA)), could be regulated and controlled by varying the concentrations of P(BA-AA) or the mass ratio of BA:AA in P(BA-AA). The experimental results indicate that 3.0-6.0 wt% of P(BA-AA) is required to obtain stable composite emulsions, and P(BA-AA) with a mass ratio of BA:AA = 1:2 is able to generate distinct core-corona structures. A mechanism of composite particle formation is proposed based on the high affinity between the PSt core and the hydrophobic segments of P(BA-A). The regular morphology of the colloidal film is expected to facilitate potential application of core-corona particles in the field of light scattering. Furthermore, the diversity of core-corona particles can be expanded by replacing P(BA-AA) corona particles with other amphiphilic particles.

  13. New perspectives on contributing factors to the monthly behavior of the aa geomagnetic index

    NASA Astrophysics Data System (ADS)

    Mendoza, Blanca; Pazos, Marni; González, Luis Xavier

    2016-12-01

    We studied the Aa geomagnetic index ( aa index daily average) behavior on a monthly timescale using data from 1868 to 2015 for cycles 11-24. We identified solar- and lunar-associated periodicities in the Aa time series and found statistically significant Aa minima values a few days before the full Moon and high Aa values during the new Moon. When considering all the cycles, it was clear that the deepest Aa minima occurred during the Aa descending activity phase. However, when the cycles were separated according to the direction of the interplanetary magnetic field (IMF), the Aa minima came from the contribution of cycles with the IMF pointing toward the Sun (Type 1). Furthermore, during the descending phase of cycles with the IMF pointing away from the Sun (Type 2), the smallest Aa index values were found along with smaller changes compared to Type 1 cases. This behavior implies that during Type 1 cycles there are larger Aa perturbations than during Type 2 cycles. It is very likely that the mechanisms responsible for the Aa monthly behavior are a combination of solar and lunar effects that depend on several factors: (a) the Moon phases (new and full Moon), (b) the phase of the solar cycle (ascending or descending), and (c) the direction of the interplanetary magnetic field (away or toward the Sun).

  14. A Status Report on the AAS Astronomy Ambassadors Program

    NASA Astrophysics Data System (ADS)

    Fienberg, Richard Tresch; Fraknoi, Andrew; Gurton, Suzanne; Hurst, Anna; Schatz, Dennis L.

    2014-06-01

    The American Astronomical Society, in partnership with the Astronomical Society of the Pacific (ASP), has launched a series of professional-development workshops and a community of practice designed to improve early-career astronomers’ ability to communicate effectively with students and the public. Called AAS Astronomy Ambassadors, the program provides training and mentoring for young astronomers, from advanced undergraduates to beginning faculty; it also provides them access to resources and a network of contacts within the astronomy education and public outreach (EPO) community. Ambassadors are provided with a library of outreach activities and resource materials suitable for a range of venues and audiences. For much of this library we are using resources developed by organizations such as the ASP, the Pacific Science Center, and the Center for Astronomy Education for other outreach programs, though some resources have been created by one of us (AF) specifically for this program. After a period of evaluation and revision, the program’s “Menu of Outreach Opportunities for Science Education” (MOOSE) is now posted on the AAS website at http://aas.org/outreach/moose-menu-outreach-opportunities-science-education.The first two Astronomy Ambassadors workshops were held at AAS meetings in January 2013 and January 2014; each served 30 young astronomers chosen from about twice that many applicants. Web-based follow-up activities are being provided through a website at the ASP designed to keep cohorts of educators trained in their programs in touch with one another. The AAS is exploring ways to fund additional workshops at future winter meetings; suggestions are most welcome. Meanwhile, the Astronomy Ambassadors trained to date have logged more than 150 outreach events, reaching many thousands of children and adults across the U.S. and Canada.

  15. Parasporal body formation via overexpression of the Cry10Aa toxin of Bacillus thuringiensis subsp. israelensis, and Cry10Aa-Cyt1Aa synergism.

    PubMed

    Hernández-Soto, Alejandro; Del Rincón-Castro, M Cristina; Espinoza, Ana M; Ibarra, Jorge E

    2009-07-01

    Bacillus thuringiensis subsp. israelensis is the most widely used microbial control agent against mosquitoes and blackflies. Its insecticidal success is based on an arsenal of toxins, such as Cry4A, Cry4B, Cry11A, and Cyt1A, harbored in the parasporal crystal of the bacterium. A fifth toxin, Cry10Aa, is synthesized at very low levels; previous attempts to clone and express Cry10Aa were limited, and no parasporal body was formed. By using a new strategy, the whole Cry10A operon was cloned in the pSTAB vector, where both open reading frames ORF1 and ORF2 (and the gap between the two) were located, under the control of the cyt1A operon and the STAB-SD stabilizer sequence characteristic of this vector. Once the acrystalliferous mutant 4Q7 of B. thuringiensis subsp. israelensis was transformed with this construct, parasporal bodies were observed by phase-contrast microscopy and transmission electron microscopy. Discrete, ca. 0.9-microm amorphous parasporal bodies were observed in the mature sporangia, which were readily purified by gradient centrifugation once autolysis had occurred. Pure parasporal bodies showed two major bands of ca. 68 and 56 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. These bands were further characterized by N-terminal sequencing of tryptic fragments using matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis, which identified both bands as the products of ORF1 and ORF2, respectively. Bioassays against fourth-instar larvae of Aedes aegypti of spore-crystal complex and pure crystals of Cry10Aa gave estimated 50% lethal concentrations of 2,061 ng/ml and 239 ng/ml, respectively. Additionally, synergism was clearly detected between Cry10A and Cyt1A, as the synergistic levels (potentiation rates) were estimated at 13.3 for the mixture of Cyt1A crystals and Cry10Aa spore-crystal complex and 12.6 for the combination of Cyt1A and Cry10Aa pure crystals.

  16. An improved OPLS-AA force field for carbohydrates.

    PubMed

    Kony, D; Damm, W; Stoll, S; Van Gunsteren, W F

    2002-11-30

    This work describes an improved version of the original OPLS-all atom (OPLS-AA) force field for carbohydrates (Damm et al., J Comp Chem 1997, 18, 1955). The improvement is achieved by applying additional scaling factors for the electrostatic interactions between 1,5- and 1,6-interactions. This new model is tested first for improving the conformational energetics of 1,2-ethanediol, the smallest polyol. With a 1,5-scaling factor of 1.25 the force field calculated relative energies are in excellent agreement with the ab initio-derived data. Applying the new 1,5-scaling makes it also necessary to use a 1,6-scaling factor for the interactions between the C4 and C6 atoms in hexopyranoses. After torsional parameter fitting, this improves the conformational energetics in comparison to the OPLS-AA force field. The set of hexopyranoses included in the torsional parameter derivation consists of the two anomers of D-glucose, D-mannose, and D-galactose, as well as of the methyl-pyranosides of D-glucose, D-mannose. Rotational profiles for the rotation of the exocyclic group and of different hydroxyl groups are also compared for the two force fields and at the ab initio level of theory. The new force field reduces the overly high barriers calculated using the OPLS-AA force field. This leads to better sampling, which was shown to produce more realistic conformational behavior for hexopyranoses in liquid simulation. From 10-ns molecular dynamics (MD) simulations of alpha-D-glucose and alpha-D-galactose the ratios for the three different conformations of the hydroxymethylene group and the average (3)J(H,H) coupling constants are derived and compared to experimental values. The results obtained for OPLS-AA-SEI force field are in good agreement with experiment whereas the properties derived for the OPLS-AA force field suffer from sampling problems. The undertaken investigations show that the newly derived OPLS-AA-SEI force field will allow simulating larger carbohydrates or

  17. Promoters of AaGL2 and AaMIXTA-Like1 genes of Artemisia annua direct reporter gene expression in glandular and non-glandular trichomes

    PubMed Central

    Jindal, Sunita; Longchar, Bendangchuchang; Singh, Alka; Gupta, Vikrant

    2015-01-01

    Herein, we report cloning and analysis of promoters of GLABRA2 (AaGL2) homolog and a MIXTA-Like (AaMIXTA-Like1) gene from Artemisia annua. The upstream regulatory regions of AaGL2 and AaMIXTA-Like1 showed the presence of several crucial cis-acting elements. Arabidopsis and A. annua seedlings were transiently transfected with the promoter-GUS constructs using a robust agro-infiltration method. Both AaGL2 and AaMIXTA-Like1 promoters showed GUS expression preferentially in Arabidopsis single-celled trichomes and glandular as well as T-shaped trichomes of A. annua. Transgenic Arabidopsis harboring constructs in which AaGL2 or AaMIXTA-Like1 promoters would control GFP expression, showed fluorescence emanating specifically from trichome cells. Our study provides a fast and efficient method to study trichome-specific expression, and 2 promoters that have potential for targeted metabolic engineering in plants. PMID:26340695

  18. Frictional conditions between alloy AA6060 aluminium and tool steel

    SciTech Connect

    Wideroee, Fredrik; Welo, Torgeir

    2011-05-04

    The frictional conditions in the new process of screw extrusion of aluminium have been investigated. The contact behaviour between the aluminum alloy and the tool steel in the extruder is vital for understanding the extrusion process. Using a compressive-rotational method for frictional measurements the conditions for unlubricated sticking friction between aluminum alloy AA6060 and tool steel at different combinations of temperatures and pressures have been investigated. In this method the samples in the form of disks are put under hydrostatic pressure while simultaneously being rotated at one end. Pins made from contrast material have been inserted into the samples to measure the deformation introduced. This approach along with 3D simulations form a method for determining the frictional conditions. The paper describes the test method and the results. It was found that the necessary pressure for sticking to occur between the aluminum AA6060 and the different parts of the extruder is heavily influenced by the temperature.

  19. Critical optical properties of AA-stacked multilayer graphenes

    NASA Astrophysics Data System (ADS)

    Chiu, Chih-Wei; Chen, Szu-Chao; Huang, Yuan-Cheng; Shyu, Feng-Lin; Lin, Ming-Fa

    2013-07-01

    The band structures and optical properties of AA-stacked multilayer graphenes are calculated by the tight-binding model and gradient approximation. For a nL-layer AA-stacked graphene, there are nL peaks at both low and middle frequencies. The threshold energy of odd-layer graphene is much lower than that of even-layer graphene for nL<10. The differences in the electronic structures and optical properties between the odd and even layers are reduced with increasing nL. When nL grows to 30 (200), the spectra of 2D graphene are almost identical to those of 3D graphite at middle (low) frequencies.

  20. HIST1H2AA — EDRN Public Portal

    Cancer.gov

    HIST1H2AA, a member of the histone 2A family, is a core component of the nucleosome. The nucleosome is a histone octamer containing two molecules each of H2A, H2B, H3 and H4 assembled in one H3-H4 heterotetramer and two H2A-H2B heterodimers. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template (the octamer wraps approximately 147 bp of DNA). Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. The HIST1H2AA gene is intronless and encodes a member of the histone H2A family. Transcripts from this gene contain a palindromic termination element.

  1. AA amyloidosis associated with systemic-onset juvenile idiopathic arthritis.

    PubMed

    Saha, Abhijeet; Chopra, Yogiraj; Theis, Jason D; Vrana, Julie A; Sethi, Sanjeev

    2013-10-01

    We report a 12-year-old boy with nephrotic syndrome due to renal AA amyloidosis. The AA amyloidosis was associated with a 3-year history of systemic-onset juvenile idiopathic arthritis. The presence of serum amyloid A protein was confirmed by laser microdissection of Congo Red-positive glomeruli and vessels followed by liquid chromatography and tandem mass spectrometry; this analysis excluded hereditary and familial amyloidosis. Aggressive management of the systemic-onset juvenile idiopathic arthritis resulted in improvement in clinical and laboratory parameters. The case represents an unusual cause of nephrotic syndrome in children. Early diagnosis of renal amyloidosis and management of systemic-onset juvenile idiopathic arthritis is paramount to preventing progression of kidney disease.

  2. Co-expression and synergism analysis of Vip3Aa29 and Cyt2Aa3 insecticidal proteins from Bacillus thuringiensis.

    PubMed

    Yu, Xiumei; Liu, Tao; Sun, Zhiguang; Guan, Peng; Zhu, Jun; Wang, Shiquan; Li, Shuangcheng; Deng, Qiming; Wang, Lingxia; Zheng, Aiping; Li, Ping

    2012-04-01

    Vegetative insecticidal protein (Vip3) from Bacillus thuringiensis shows high activity against lepidopteran insects. Cytolytic δ-endotoxin (Cyt) also has high toxicity to dipteran larvae and synergism with other crystal proteins (Cry), but synergism between Cyt and Vip3 proteins has not been tested. We analyzed for synergism between Cyt2Aa3 and Vip3Aa29. Both cyt2Aa3 and vip3Aa29 genes were co-expressed in Escherichia coli strain BL21 carried on vector pCOLADuet-1. Vip3Aa29 showed insecticidal activity against Chilo suppressalis and Spodoptera exigua, with 50% lethal concentration (LC(50)) at 24.0 and 36.6 μg ml(-1), respectively. It could also inhibit Helicoverpa armigera growth, with 50% inhibition concentration at 22.6 μg ml(-1). While Cyt2Aa3 was toxic to Culex quinquefasciatus (LC(50): 0.53 μg ml(-1)) and Chironomus tepperi (LC(50): 36 μg ml(-1)), it did not inhibit C. suppressalis, S. exigua, and H. armigera. However, the co-expression of Cyt2Aa3 and Vip3Aa29 showed synergistic effect on C. suppressalis and S. exigua, and the individual activities were strengthened 3.35- and 4.34-fold, respectively. The co-expression had no synergism against C. tepperi and H. armigera, but exerted some antagonistic effect on Cx. quinquefasciatus. The synergism between Cyt2Aa and Vip3Aa was thus discovered for the first time, which confirmed that Cyt toxin can enhance the toxicity of other toxins against some non-target insects. By synergism analysis, the effectiveness of microbial insecticides can be verified.

  3. Cell volume regulation in hemoglobin CC and AA erythrocytes

    SciTech Connect

    Berkowitz, L.R.; Orringer, E.P.

    1987-03-01

    Swelling hemoglobin CC erythrocytes stimulates a ouabain-insensitive K flux that restores original cell volume. Studies were performed with the K analog, /sup 86/Rb. This volume regulatory pathway was characterized for its anion dependence, sensitivity to loop diuretics, and requirement for Na. The swelling-induced K flux was eliminated if intracellular chloride was replaced by nitrate and both swelling-activated K influx and efflux were partially inhibited by 1 mM furosemide or bumetanide. K influx in swollen hemoglobin CC cells was not diminished when Na in the incubation medium was replaced with choline, indicating Na independence of the swelling-induced flux. Identical experiments with hemoglobin AA cells also demonstrated a swelling-induced increase in K flux, but the magnitude and duration of this increase were considerably less than that seen with hemoglobin CC cells. The increased K flux in hemoglobin AA cells was likewise sensitive to anion replacement and to loop diuretics and did not require the presence of Na. These data indicate that a volume-activated K pathway with similar transport characteristics exists in both hemoglobin CC and AA red cells.

  4. Long-term biases in geomagnetic K and aa indices

    USGS Publications Warehouse

    Love, J.J.

    2011-01-01

    Analysis is made of the geomagnetic-activity aa index and its source K-index data from groups of ground-based observatories in Britain, and Australia, 1868.0-2009.0, solar cycles 11-23. The K data show persistent biases, especially for high (low) K-activity levels at British (Australian) observatories. From examination of multiple subsets of the K data we infer that the biases are not predominantly the result of changes in observatory location, localized induced magnetotelluric currents, changes in magnetometer technology, or the modernization of K-value estimation methods. Instead, the biases appear to be artifacts of the latitude-dependent scaling used to assign K values to particular local levels of geomagnetic activity. The biases are not effectively removed by weighting factors used to estimate aa. We show that long-term averages of the aa index, such as annual averages, are dominated by medium-level geomagnetic activity levels having K values of 3 and 4. ?? 2011 Author(s).

  5. Isolation of a cytochrome aa3 gene from Bradyrhizobium japonicum

    PubMed Central

    O'Brian, Mark R.; Maier, Robert J.

    1987-01-01

    Bradyhizobium japonicum strain LO501 is a Tn5-induced mutant that does not express the terminal oxidase cytochrome aa3 (cytochrome-c oxidase, EC 1.9.3.1). Two and one-half kilobase pairs of LO501 genomic DNA that flanks the transposon was isolated and used as a hybridization probe to obtain the wild-type gene from a cosmid library. Two subcloned fragments from two of the isolated cosmids were ligated into broad host range vectors, and restriction maps of these fragments were generated. The resultant plasmids, pCA1 and pBL33, each contained DNA homologous to that mutated in strain LO501. The two plasmids were each introduced into strain LO501 by conjugal transfer, and it was found that pCA1, but not pBL33, complemented the oxidase mutant. The transconjugant strain LO501[pCA1] expressed wild-type levels of cytochrome aa3, as discerned spectrophotometrically, and had restored N,N,N′,N′-tetramethyl-p-phenylenediamine oxidase activity. Furthermore, the frequency of complementation of LO501 cells that received pCA1 by conjugation was 1.0, demonstrating that pCA1 complemented the mutant in trans. The results show that pCA1 contains the entire wild-type gene that was mutated in strain LO501, and this gene is required for cytochrome aa3 expression. Images PMID:16593835

  6. The amino acid sequence of protein AA from a burro (Equus asinus).

    PubMed

    Sletten, Knut; Johnson, Kenneth H; Westermark, Per

    2003-09-01

    The primary structure of amyloid fibril protein AA of a burro has been determined by Edman degradation. The 80 amino acid residue long protein shows strong resemblance to that of other mammalian AA-proteins and differs from equine protein AA at 5 positions: Burro/horse positions 20 (Q/N), 44 (R,Q, K/K,Q), 59 (G,L/G,A), 61 (Q/E) and 65 (N/R).

  7. Aedes cadherin mediates the in vivo toxicity of the Cry11Aa toxin to Aedes aegypti

    PubMed Central

    Aimanova, Karlygash G.; Gill, Sarjeet S.

    2014-01-01

    Cadherin plays an important role in the toxicity of Bacillus thuringiensis Cry proteins. We previously cloned a full-length cadherin from Aedes aegypti larvae and reported this protein binds Cry11Aa toxin from B. thuringiensis subsp. israelensis with high affinity, ≈ 16.7 nM. Based on these results, we investigated if Aedes cadherin is involved in the in vivo toxicity of Cry11Aa toxin to Ae. aegypti. We established a mosquito cell line stably expressing the full-length Aedes cadherin and transgenic mosquitoes with silenced Aedes cadherin expression. Cells expressing the Aedes cadherin showed increased sensitivity to Cry11Aa toxin. Cry11Aa toxin at 400 nM killed approximately 37% of the cells in 3 h. Otherwise, transgenic mosquitoes with silenced Aedes cadherin expression showed increased tolerance to Cry11Aa toxin. Furthermore, cells expressing Aedes cadherin triggered Cry11Aa oligomerization. These results show the Aedes cadherin plays a pivotal role in Cry11Aa toxicity to Ae. aegypti larvae by mediating Cry11Aa oligomerization. However, since high toxicity was not obtained in cadherin-expressing cells, an additional receptor may be needed for manifestation of full toxicity. Moreover, cells expressing Aedes cadherin were sensitive to Cry4Aa and Cry11Ba but not Cry4Ba. However transgenic mosquitoes with silenced Aedes cadherin expression showed no tolerance to Cry4Aa, Cry4Ba, and Cry11Ba toxins. These results suggest that while Aedes cadherin may mediate Cry4Aa and Cry11Ba toxicity, this cadherin but is not the main receptor of Cry4Aa, Cry4Ba and Cry11Ba toxin in Ae. aegypti. PMID:25064814

  8. Aedes cadherin mediates the in vivo toxicity of the Cry11Aa toxin to Aedes aegypti.

    PubMed

    Lee, Su-Bum; Chen, Jianwu; Aimanova, Karlygash G; Gill, Sarjeet S

    2015-06-01

    Cadherin plays an important role in the toxicity of Bacillus thuringiensis Cry proteins. We previously cloned a full-length cadherin from Aedes aegypti larvae and reported this protein binds Cry11Aa toxin from B. thuringiensis subsp. israelensis with high affinity, ≈16.7nM. Based on these results, we investigated if Aedes cadherin is involved in the in vivo toxicity of Cry11Aa toxin to Ae. aegypti. We established a mosquito cell line stably expressing the full-length Aedes cadherin and transgenic mosquitoes with silenced Aedes cadherin expression. Cells expressing the Aedes cadherin showed increased sensitivity to Cry11Aa toxin. Cry11Aa toxin at 400nM killed approximately 37% of the cells in 3h. Otherwise, transgenic mosquitoes with silenced Aedes cadherin expression showed increased tolerance to Cry11Aa toxin. Furthermore, cells expressing Aedes cadherin triggered Cry11Aa oligomerization. These results show the Aedes cadherin plays a pivotal role in Cry11Aa toxicity to Ae. aegypti larvae by mediating Cry11Aa oligomerization. However, since high toxicity was not obtained in cadherin-expressing cells, an additional receptor may be needed for manifestation of full toxicity. Moreover, cells expressing Aedes cadherin were sensitive to Cry4Aa and Cry11Ba, but not Cry4Ba. However transgenic mosquitoes with silenced Aedes cadherin expression showed no tolerance to Cry4Aa, Cry4Ba, and Cry11Ba toxins. These results suggest that while Aedes cadherin may mediate Cry4Aa and Cry11Ba toxicity, this cadherin but is not the main receptor of Cry4Aa, Cry4Ba and Cry11Ba toxin in Ae. aegypti.

  9. Computational Investigation of Hardness Evolution During Friction-Stir Welding of AA5083 and AA2139 Aluminum Alloys

    DTIC Science & Technology

    2011-01-01

    is combined with the basic physical metallurgy of two wrought aluminum alloys to predict/assess their FSW behaviors. The two alloys selected are AA5083... Aluminum Alloys Report Title ABSTRACT A fully coupled thermo-mechanical finite-element analysis of the friction-stir welding ( FSW ) process developed in our...previous work is combined with the basic physical metallurgy of two wrought aluminum alloys to predict/assess their FSW behaviors. The two alloys

  10. Through-thickness recrystallization characteristics of a laminated AA3xxx–AA6xxx aluminum alloy system

    SciTech Connect

    Liao, L.H.; Jin, H.; Gallerneault, M.; Esmaeili, S.

    2015-03-15

    The through-thickness annealing behavior of a laminated AA3xxx–AA6xxx alloy system at 300 °C has been studied by scanning electron microscopy, electron backscatter diffraction analysis, electron probe micro-analysis, differential scanning calorimetry, and hardness measurement. Results show that the recrystallization process starts at the interface region between the AA3xxx (clad) and AA6xxx (core) layers. Subsequently, the recrystallization process front progresses into the core layer, while the clad layer is the last region to recrystallize. It is also found that precipitation precedes recrystallization in the entire laminate at the investigated temperature. The preferential onset of recrystallization at the interface region is attributed to the net driving pressure being the highest in this region. The factors that lead to such enhanced net driving pressure are (a) deformation incompatibility between the two alloy layers, (b) lower solute content of the interface, which also leads to lower volume fraction of precipitates, and (c) an accelerated rate of precipitate coarsening due to the presence of a higher density of dislocations. The gradual progress of recrystallization from the interface towards the core layer is dictated by precipitate coarsening and the dependence of its rate on the density of deformation-induced dislocations. The lower driving pressure due to lower work hardening capacity, high solute drag pressure due to Mn, and additional Zener drag from precipitates that form due to solute redistribution during annealing explain the late initiation of recrystallization in the clad layer. - Highlights: • The through-thickness recrystallization of a laminated system is investigated. • The early onset of recrystallization at the interface is discussed. • The effects of precipitation and coarsening on recrystallization are analyzed.

  11. AA amyloidosis in the renal allograft: a report of two cases and review of the literature

    PubMed Central

    Rojas, Rebecca; Josephson, Michelle A.; Chang, Anthony; Meehan, Shane M.

    2012-01-01

    AA amyloidosis is a disorder characterized by the abnormal formation, accumulation and systemic deposition of fibrillary material that frequently involves the kidney. Recurrent AA amyloidosis in the renal allograft has been documented in patients with tuberculosis, familial Mediterranean fever, ankylosing spondylitis, chronic pyelonephritis and rheumatoid arthritis. De novo AA amyloidosis is rarely described. We report two cases of AA amyloidosis in the renal allograft. Our first case is a 47-year-old male with a history of ankylosing spondylitis who developed end-stage renal disease reportedly from tubulointerstitial nephritis from non-steroidal anti-inflammatory agent use. A biopsy was never performed. One year after transplantation, AA amyloidosis was identified in the femoral head and 8 years post-transplantation, AA amyloidosis was identified in the renal allograft. He was treated with colchicine and adalimumab and has stable renal function at 1 year-follow-up. Our second case is a 57-year-old male with a long history of intravenous drug use and hepatitis C infection who developed end-stage kidney disease due to AA amyloidosis. Our second patient's course was complicated by renal adenovirus, pulmonary aspergillosis and hepatitis C with AA amyloidosis subsequently being identified in the allograft 2.5 years post-transplantation. Renal allograft function remains stable 4-years post-transplantation. These reports describe clinical and pathologic features of two cases of AA amyloidosis presenting with proteinuria and focal involvement of the renal allograft. PMID:22833808

  12. Overexpression of AaWRKY1 Leads to an Enhanced Content of Artemisinin in Artemisia annua

    PubMed Central

    Jiang, Weimin; Fu, Xueqing; Pan, Qifang; Tang, Yueli; Shen, Qian; Lv, Zongyou; Yan, Tingxiang; Shi, Pu; Li, Ling; Zhang, Lida; Wang, Guofeng; Sun, Xiaofen; Tang, Kexuan

    2016-01-01

    Artemisinin is an effective component of drugs against malaria. The regulation of artemisinin biosynthesis is at the forefront of artemisinin research. Previous studies showed that AaWRKY1 can regulate the expression of ADS, which is the first key enzyme in artemisinin biosynthetic pathway. In this study, AaWRKY1 was cloned, and it activated ADSpro and CYPpro in tobacco using dual-LUC assay. To further study the function of AaWRKY1, pCAMBIA2300-AaWRKY1 construct under 35S promoter was generated. Transgenic plants containing AaWRKY1 were obtained, and four independent lines with high expression of AaWRKY1 were analyzed. The expression of ADS and CYP, the key enzymes in artemisinin biosynthetic pathway, was dramatically increased in AaWRKY1-overexpressing A. annua plants. Furthermore, the artemisinin yield increased significantly in AaWRKY1-overexpressing A. annua plants. These results showed that AaWRKY1 increased the content of artemisinin by regulating the expression of both ADS and CYP. It provides a new insight into the mechanism of regulation on artemisinin biosynthesis via transcription factors in the future. PMID:27064403

  13. Experimental transmission of systemic AA amyloidosis in autoimmune disease and type 2 diabetes mellitus model mice

    PubMed Central

    Maeda, Mayuko; Murakami, Tomoaki; Muhammad, Naeem; Inoshima, Yasuo; Ishiguro, Naotaka

    2016-01-01

    AA amyloidosis is a protein misfolding disease characterized by extracellular deposition of amyloid A (AA) fibrils. AA amyloidosis has been identified in food animals, and it has been postulated that AA amyloidosis may be transmissible to different animal species. Since the precursor protein of AA fibrils is serum amyloid A (SAA), which is an inflammatory acute phase protein, AA amyloidosis is considered to be associated with inflammatory diseases such as rheumatoid arthritis. Chronic diseases such as autoimmune disease and type 2 diabetes mellitus could be potential factors for AA amyloidosis. In this study, to examine the relationship between the induction of AA amyloidosis and chromic abnormalities such as autoimmune disease or type 2 diabetes mellitus, amyloid fibrils from mice, cattle, or chickens were experimentally injected into disease model mice. Wild-type mice were used as controls. The concentrations of SAA, IL-6, and IL-10 in autoimmune disease model mice were higher than those of control mice. However, induction of AA amyloidosis in autoimmune disease and type 2 diabetes mellitus model mice was lower than that in control mice, and the amount of amyloid deposits in the spleens of both mouse models was lower than that of control mice according to Congo red staining and immunohistochemistry. These results suggest that factors other than SAA levels, such as an inflammatory or anti-inflammatory environment in the immune response, may be involved in amyloid deposition. PMID:27321428

  14. Microsolvation of the acetanilide cation (AA(+)) in a nonpolar solvent: IR spectra of AA(+)-L(n) clusters (L = He, Ar, N2; n ≤ 10).

    PubMed

    Schmies, Matthias; Patzer, Alexander; Schütz, Markus; Miyazaki, Mitsuhiko; Fujii, Masaaki; Dopfer, Otto

    2014-05-07

    Infrared photodissociation (IRPD) spectra of mass-selected cluster ions of acetanilide (N-phenylacetamide), AA(+)-Ln, with the ligands L = He (n = 1-2), Ar (n = 1-7), and N2 (n = 1-10) are recorded in the hydride stretch (amide A, νNH, νCH) and fingerprint (amide I-III) ranges of AA(+) in its (2)A'' ground electronic state. Cold AA(+)-Ln clusters are generated in an electron impact ion source, which predominantly produces the most stable isomer of a given cluster ion. Systematic vibrational frequency shifts of the N-H stretch fundamentals (νNH) provide detailed information about the sequential microsolvation process of AA(+) in a nonpolar (L = He and Ar) and quadrupolar (L = N2) solvent. In the most stable AA(+)-Ln clusters, the first ligand forms a hydrogen bond (H-bond) with the N-H proton of trans-AA(+) (t-AA(+)), whereas further ligands bind weakly to the aromatic ring (π-stacking). There is no experimental evidence for complexes with the less stable cis-AA(+) isomer. Quantum chemical calculations at the M06-2X/aug-cc-pVTZ level confirm the cluster growth sequence derived from the IR spectra. The calculated binding energies of De(H) = 720 and 1227 cm(-1) for H-bonded and De(π) = 585 and 715 cm(-1) for π-bonded Ar and N2 ligands in t-AA(+)-L are consistent with the observed photofragmentation branching ratios of AA(+)-Ln. Comparison between charged and neutral AA((+))-L dimers indicates that ionization switches the preferred ion-ligand binding motif from π-stacking to H-bonding. Electron removal from the HOMO of AA(+) delocalized over both the aromatic ring and the amide group significantly strengthens the C[double bond, length as m-dash]O bond and weakens the N-H bond of the amide group.

  15. Immunological evaluation of OMV(PagL)+Bap(1-487aa) and AbOmpA(8-346aa)+Bap(1-487aa) as vaccine candidates against Acinetobacter baumannii sepsis infection.

    PubMed

    Badmasti, Farzad; Ajdary, Soheila; Bouzari, Saeid; Fooladi, Abbas Ali Imani; Shahcheraghi, Fereshteh; Siadat, Seyed Davar

    2015-10-01

    Acinetobacter baumannii is an important nosocomial pathogen that causes a high morbidity and mortality rate in infected patients with sepsis form. The surface exposed virulence proteins and serum resistance factors helping to dissemination of this bacterium to bloodstream are the most promising vaccine candidates against this microorganism. In this project we immunologically evaluated OMV(PagL)+Bap(1-487aa) and AbOmpA (8-346aa)+Bap(1-487aa) as combination forms as well as Bap(1-487aa), AbOmpA(8-346aa) and OMV(PagL) singly, with addition of alum adjuvant as vaccine candidates. The titers of total IgG, IgG1 and IgG2c as well as concentration of IL-4 and IFN-γ and survival rates were measured in a C57BL/6 murine model with disseminated sepsis. The ratio of IgG1/IgG2c and profile of IL-4/IFN-γ in OMV (PagL)+Bap (1-487aa) formulation shows the humoral and cellular immune responses have been induced robustly and have created a full protection against A. baumannii ATCC 19606 and MDR AB-44 strains. We found that the two combination vaccine candidates were protective and induced both Th1 and Th2 responses.

  16. Introducing the AAS Working Group on Astroinformatics and Astrostatistics

    NASA Astrophysics Data System (ADS)

    Ivezic, Zeljko

    2014-01-01

    In response to two White Papers submitted to the Astro2010 Decadal Survey (1,2), a new AAS Working Group on Astroinformatics and Astrostatistics (WGAA) has been approved by the AAS Council at the 220th Meeting, June 2012, in Anchorage. The motivation for this WG is the growing importance of the interface between astronomy and various branches of applied mathematics, computer science and the emerging field of data science. With the new data-intensive projects envisioned for the coming decade, the need for advice derived from the focused attention of a group of AAS members who work in these areas is bound to increase. The Working Group is charged with spreading awareness of rapidly advancing computational techniques, sophsticated statistical methods, and highly capble software to further the goals of astronomical and astrophysical research. The three main strategic goals adopted by the WGAA Steering Committee for the next few years are to: (i) develop, organize and maintain methodological resources (such as software tools, papers, books, and lectures); (ii) enhance human resources (such as foster the creation of career paths, establish a Speakers' Bureau, establish and maintain an archived discussion forum, enable periodic news distribution); and (iii) organize topical meetings. The WGAA Steering Committee at this time includes twelve members: Kirk Borne, George Djorgovski, Eric Feigelson, Eric Ford, Alyssa Goodman, Joe Hilbe, Zeljko Ivezic (chair), Ashish Mahabal, Aneta Siemiginowska, Alex Szalay, Rick White, and Padma Yanamandra-Fisher. I will summarize our accomplishments since July 2012. (1) Astroinformatics: A 21st Century Approach to Astronomy (Borne & 90 coauthors), (2) The Astronomical Information Sciences: A Keystone for 21st-Century Astronomy (Loredo & 72 coauthors)

  17. 184AA3: A Xenograft Model of ER+ Breast Adenocarcinoma

    PubMed Central

    Hines, William C.; Kuhn, Irene; Thi, Kate; Chu, Berbie; Stanford-Moore, Gaelen; Sampayo, Rocío; Garbe, James C.; Stampfer, Martha; Borowsky, Alexander D.; Bissell, Mina

    2015-01-01

    Purpose Despite the prevalence and significant morbidity resulting from estrogen receptor positive (ER+) breast adenocarcinomas, there are only a few models of this cancer subtype available for drug development, and arguably none for studying etiology. Those models that do exist have questionable clinical relevance. Methods Given our goal of developing luminal models, we focused on six cell lines derived by minimal mutagenesis from normal human breast cells, and asked if any could generate clinically relevant xenografts, which we then extensively characterized. Results Xenografts of one cell line, 184AA3, consistently formed ER+ adenocarcinomas that had a high proliferative rate and other features consistent with “luminal B” intrinsic subtype. Squamous and spindle cell/mesenchymal differentiation was absent, in stark contrast to other cell lines that we examined or others have reported. We explored intratumoral heterogeneity produced by 184AA3 by immunophenotyping xenograft tumors and cultured cells, and characterized marker expression by immunofluorescence and flow cytometry. A CD44High subpopulation was discovered, yet their tumor forming ability was far less than CD44Low cells. Single cell cloning revealed the phenotypic plasticity of 184AA3, consistent with the intratumoral heterogeneity observed in xenografts. Characterization of ER expression in cultures revealed ER protein and signaling is intact, yet when estrogen was depleted in culture, and in vivo, it did not impact cell or tumor growth, analogous to therapeutically resistant ER+ cancers. Conclusions This model is appropriate for studies of the etiology of ovarian hormone independent adenocarcinomas, for identification of therapeutic targets, predictive testing and drug development. PMID:26661596

  18. 23. VIEW OF SECTION DRAWINGS. THE SECTION LINES FOR AA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. VIEW OF SECTION DRAWINGS. THE SECTION LINES FOR A-A AND C-C CUT THE BUILDING EAST-WEST; SECTION LINE B-B CUTS THE BUILDING NORTH-SOUTH. THE ORIGINAL DRAWING HAS BEEN ARCHIVED ON MICROFILM. THE DRAWING WAS REPRODUCED AT THE BEST QUALITY POSSIBLE. LETTERS AND NUMBERS IN THE CIRCLES INDICATE FOOTER AND/OR COLUMN LOCATIONS. - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  19. Antacids Revisited with Modern Chemical Instruments: GCMS, AAS, and CCT

    NASA Astrophysics Data System (ADS)

    Burden, Stanley L.; Petzold, Christopher J.

    1999-11-01

    Data from multiple analytical methods are often required to identify or characterize samples. Typical undergraduate experiments utilize only one or two techniques in a given experiment. This paper describes a novel experiment that requires students to obtain and interpret data from several analytical techniques to identify the brand name of a commercial antacid. Students receive a ground sample of a commercial antacid. They are required to design a set of experiments utilizing computer controlled titrations (CCT), atomic absorption (AA), gas chromatography-mass spectroscopy (GCMS), and careful quantitative manual titrations using a visual indicator of their choice to determine the brand name of their sample from a list of six to eight choices.

  20. Professional Ethics in Astronomy: The AAS Ethics Statement

    NASA Astrophysics Data System (ADS)

    Marvel, Kevin B.

    2013-01-01

    It is fundamental to the advancement of science that practicing scientists adhere to a consistent set of professional ethical principles. Recent violations of these principles have led a decreased trust in the process of science and scientific results. Although astronomy is less in the spotlight on these issues than medical science or climate change research, it is still incumbent on the field to follow sound scientific process guided by basic ethical guidelines. The American Astronomical Society, developed a set of such guidelines in 2010. This contribution summarizes the motivation and process by which the AAS Ethics Statement was produced.

  1. Reframing Spirituality: AA, the 12 Steps, and the Mental Health Counselor.

    ERIC Educational Resources Information Center

    Hanna, Fred J.

    1992-01-01

    Surveys literature and explores ways to understand spirituality in Alcoholics Anonymous (AA). Topics explored range from Jungian and Jamesian psychology, to Stoicism, the work of Bateson, and transpersonal psychology and therapy. Speculates that difficulty some mental health counselors have in accepting AA as therapy could be a result of…

  2. AR, HEA and AAS in Rural Development Projects--Benchmarking towards the Best Processes.

    ERIC Educational Resources Information Center

    Westermarck, Harri

    In most countries, agricultural research (AR), institutions of higher education in agriculture (HEA), and agricultural advisory services (AAS) function as separate agencies. So far, in most countries, AR, HEA, and AAS have not had a common vision for rural development. In Finland, domination of agricultural production in Finland has led to a lack…

  3. Bacterial cellulose based hydrogel (BC-g-AA) and preliminary result of swelling behavior

    SciTech Connect

    Hakam, Adil; Lazim, Azwan Mat; Abdul Rahman, I. Irman

    2013-11-27

    In this study, hydrogel based on Bacterial cellulose (BC) or local known as Nata de Coco, which grafted with monomer: Acrylic acid (AA) is synthesis by using gamma radiation technique. These hydrogel (BC-g-AA) has unique characteristic whereby responsive to pH buffer solution.

  4. Interfacial characteristics and properties of a low-clad-ratio AA4045/AA3003 cladding billet fabricated by semi-continuous casting

    NASA Astrophysics Data System (ADS)

    Han, Xing; Zhang, Hai-tao; Shao, Bo; Li, Lei; Qin, Ke; Cui, Jian-zhong

    2016-09-01

    A low-clad-ratio AA4045/AA3003 cladding billet was fabricated using a semi-continuous casting process and was subsequently extruded indirectly into a cladding pipe. The temperature distribution near the interface was measured. The microstructures, elemental distribution, Vickers hardness around the bonding interface, and the interfacial shear strength were examined. The results showed that the interface temperature rebounded when AA4045 melt contacted the supporting layer. The two alloys bonded well, with few defects, via the diffusion of Si and Mn in the temperature range from 569°C to 632°C. The mean shear strength of the bonding interface was 82.3 MPa, which was greater than that of AA3003 (75.8 MPa), indicating that the two alloys bonded with each other metallurgically via elemental interdiffusion. Moreover, no relative slip occurred between the two alloys during the extrusion process.

  5. Co-expression of the mosquitocidal toxins Cyt1Aa and Cry11Aa from Bacillus thuringiensis subsp. israelensis in Asticcacaulis excentricus.

    PubMed

    Zheng, Dasheng; Valdez-Cruz, Norma Adriana; Armengol, Gemma; Sevrez, Chloe; Munoz-Olaya, Jose Maurilio; Yuan, Zhiming; Orduz, Sergio; Crickmore, Neil

    2007-01-01

    The cyt1Aa gene from Bacillus thuringiensis subsp. israelensis (Bti), whose product synergizes other mosquitocidal toxins, and functions as a repressor of resistance developed by mosquitoes against Bacilli insecticides, was introduced into the aquatic Gram-negative bacterium Asticcacaulis excentricus alongside the cry11Aa gene. The genes were introduced as an operon, but although mRNA was detected for both genes, no Cyt1Aa toxin was detected. Both proteins were expressed using a construct in which a promoter was inserted upstream of each gene. Recombinant A. excentricus expressing both toxins was found to be approximately twice as toxic to third instar larvae of Culex quinquefasciatus as transformants expressing just Cry11Aa.

  6. 40 CFR Appendix A to Subpart Aa of... - Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart AA

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) Alternative Test Method Yes. 63.7(g) Data Analysis Yes. 63.7(h) Waiver of Tests Yes. 63.8(a)(1) Monitoring...) Alternative to RATA Test No Subpart AA does not require CEMS. 63.8(g)(1) Data Reduction Yes. 63.8(g)(2) No...) COMS Data Reports No Subpart AA does not require COMS. 63.10(f) Recordkeeping/Reporting Waiver Yes....

  7. 40 CFR Appendix A to Subpart Aa of... - Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart AA

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) Alternative Test Method Yes. 63.7(g) Data Analysis Yes. 63.7(h) Waiver of Tests Yes. 63.8(a)(1) Monitoring...) Alternative to RATA Test No Subpart AA does not require CEMS. 63.8(g)(1) Data Reduction Yes. 63.8(g)(2) No...) COMS Data Reports No Subpart AA does not require COMS. 63.10(f) Recordkeeping/Reporting Waiver Yes....

  8. 17 CFR 249.801 - Form X-15AA-1, for application for registration as a national securities association or...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Form X-15AA-1, for application....801 Form X-15AA-1, for application for registration as a national securities association or affiliated...). Editorial Note: For Federal Register citations affecting Form X-15AA-1, see the List of CFR...

  9. 33 CFR 110.72aa - Elizabeth River Spectator Vessel Anchorage Areas, between Norfolk and Portsmouth, Virginia.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Anchorage Areas, between Norfolk and Portsmouth, Virginia. 110.72aa Section 110.72aa Navigation and... Anchorage Areas § 110.72aa Elizabeth River Spectator Vessel Anchorage Areas, between Norfolk and Portsmouth, Virginia. (a) Special Anchorage Areas. (1) The waters of the Elizabeth River bounded by the shore and...

  10. 17 CFR 240.13Aa-2T - Interim rule for reporting pre-enactment security-based swap transactions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...-enactment security-based swap transactions. 240.13Aa-2T Section 240.13Aa-2T Commodity and Securities....13Aa-2T Interim rule for reporting pre-enactment security-based swap transactions. (a) Definitions. For... Exchange Act of 1934, as amended; (3) Major security-based swap participant shall have the meaning...

  11. 17 CFR 249.801 - Form X-15AA-1, for application for registration as a national securities association or...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Form X-15AA-1, for application....801 Form X-15AA-1, for application for registration as a national securities association or affiliated...). Editorial Note: For Federal Register citations affecting Form X-15AA-1, see the List of CFR...

  12. 17 CFR 249.801 - Form X-15AA-1, for application for registration as a national securities association or...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 3 2013-04-01 2013-04-01 false Form X-15AA-1, for application....801 Form X-15AA-1, for application for registration as a national securities association or affiliated...). Editorial Note: For Federal Register citations affecting Form X-15AA-1, see the List of CFR...

  13. 17 CFR 249.801 - Form X-15AA-1, for application for registration as a national securities association or...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Form X-15AA-1, for application....801 Form X-15AA-1, for application for registration as a national securities association or affiliated...). Editorial Note: For Federal Register citations affecting Form X-15AA-1, see the List of CFR...

  14. 17 CFR 249.801 - Form X-15AA-1, for application for registration as a national securities association or...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 3 2012-04-01 2012-04-01 false Form X-15AA-1, for application....801 Form X-15AA-1, for application for registration as a national securities association or affiliated...). Editorial Note: For Federal Register citations affecting Form X-15AA-1, see the List of CFR...

  15. DFW microburst model based on AA-539 data

    NASA Technical Reports Server (NTRS)

    Grantham, Walter J.; Roetcisoender, Guy G.; Parks, Edwin K.

    1990-01-01

    Analysis of the August 2, 1985 crash for an L-1011 jumbo jet (DL-191) on approach to the Dallas-Ft. Worth International Airport (DFW) in a thunderstorm indicates that the severe windshear microburst that caused the crash was composed not only of a strong downflow and outflow but also included several large-scale vortex rings entrained in the flowfield. This paper presents a detailed two-dimensional model of the DFW microburst based on data from the MD-80 (AA-539) that followed behind DL-191 and flew through the microburst about two minutes after the crash of DL-191. The model was developed using wind-vector and flight-path data reconstructed by NASA Ames Research Center and a combination of interactive graphics and least-squares error best fit between the modeled and measured wind vectors along the AA-539 flight path. The model indicates that the flowfield contains some significant elements and vortices not previously reported. The alternating direction of rotation of the vortices in the model suggests a microburst structure based on a von Karman vortex street rather than on a Kelvin-Helmholtz instability. The model also indicates that the reconstructed wind-vector data contain a time lag of at least one second in the horizontal winds.

  16. Springback analysis on AA 6061 aluminum alloy sheets

    NASA Astrophysics Data System (ADS)

    Ramulu, Perumalla Janaki; Rao, P. Srinivasa; Yimer, Wassihun

    2016-10-01

    In automotive industry, sheet metal forming process play a key role with respect to economy and weight reduction ratio. In sheet metal forming, one of the operations is bending operation in which sheet will not go under sever deformation. The end components are made by applying the continuous load on the sheet in the bending process. In bending process, elastic limits of materials are exceeded, but flow limit thereof cannot be exceeded. Therefore, the material still keeps a portion of its original flexibility character. When the load is released, the material on forcing compress side tries to enlarge, whereas the material on tensile side tries to shrink. As a result, the material tries to spring back and the bended material by flexing slightly tries to open. Springback varies according to thickness of the material, material and process parameters, type of material, period when punch load stays on the material, dimensions of die, force applied, and bending radius. In order to make bending at a desired angle, springback amounts should be avoided. In the present work, experimentation on AA 6061 alloy sheet springback analysis has done with seven different rolling directions. Results are noted with respect to load, displacement, and die angle on the springback effect. It observed that springback affect is existed notably in the AA 6061 alloys with respect to die angle.

  17. AAS Publishing News: Preparing Your Manuscript Just Got Easier

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-03-01

    Watermarking using the command watermark{DRAFT, v2}.Are you an astronomer considering submitting a paper to an AAS journal (i.e., AJ, ApJ, ApJ Letters, or ApJ Supplements)? If so, this post is for you! Read on to find out about the exciting new things you can do with the AASs newest LaTeX class file, available for download now.Why the Update?AAS publishing has maintained a consistent class file for LaTeX manuscript preparation for the past decade. But academic publishing is changing rapidly in todays era of electronic journals! Since its journals went fully electronic, the AAS has been continuously adding new publishing capabilities based on the recommendations of the Journals Task Force and the needs and requests of AAS authors. The AASs manuscript preparation tools are now being updated accordingly.Whats New in AASTex 6.0?There are many exciting new features and capabilities in AASTex 6.0. Here are just a few:Tracking options for author revisions include added{text}, deleted{text}, replaced{old}{new}, and explain{text}.Based on emulateapjDo you use the popular class file emulateapj to prepare your manuscripts? AASTex 6.0 is based on emulateapj, rather than on the older AASTex 5.2 (though 5.2 is still supported). This means that it is easy to produce a double-columned, single-spaced, and astro-ph-ready manuscript. Since two thirds of the AAS journals authors use emulateapj, this transition was designed to make manuscript preparation and sharing an easier and more seamless process.Tools for collaborationsDo you work in a large collaboration? AASTex now includes new tools to make preparing a manuscript within a collaboration easier. Drafts can now be watermarked to differentiate between versions. New markup for large author lists streamlines the display so that readers can access article information immediately, yet they can still access the full author list and affiliations at the end of the paper. And author revision markup allows members of a collaboration to

  18. Goldsinny wrasse (Ctenolabrus rupestris) is an extreme vtgAa-type pelagophil teleost.

    PubMed

    Kolarevic, Jelena; Nerland, Audun; Nilsen, Frank; Finn, Roderick Nigel

    2008-06-01

    During oocyte maturation in the goldsinny wrasse (Ctenolabrus rupestris) extensive proteolysis of yolk proteins generates a large pool of free amino acids that drive hydration of the pelagic egg. By cloning hepatic vitellogenins (vtg) and using mass spectrometry, N-terminal microsequencing, and Western-immunoblotting to identify the yolk proteins (Yp), we show that multiple forms of vitellogenin mRNAs (vtgAa, vtgAb, and vtgC) are expressed in the liver, but only a single major class of the Yps derived from vtgAa predominates in the oocytes. Some Yps derived from vtgAb and vtgC appear also to be incorporated in the oocytes and eggs, but only at background levels. During oocyte hydration the vtgAa-derived lipovitellin heavy chain (LvH-Aa) and its cleavage variants are completely degraded leaving only a processed lipovitellin light chain (LvL-Aa) fragment as the major yolk protein for embryonic development. The maturational cleavage site of the LvL-Aa is identified as two amino acids downstream from the conserved Tyr(1168) of VtgAa in Atlantic halibut. In addition, although a beta'-component (approximately 18 kDa) is present in the oocytes, it is not fully degraded during the hydration process.

  19. Daily Aa-nat gene expression in the camel (Camelus dromedarius) pineal gland.

    PubMed

    El Allali, Khalid; Sinitskaya, Natalia; Bothorel, Béatrice; Achaaban, Rachid; Pévet, Paul; Simonneaux, Valérie

    2008-09-01

    Arylalkylamine N-acetyltransferase (AA-NAT) is the rhythm-generating enzyme for the synthesis of pineal melatonin. Molecular investigations have revealed two biological models for the activation of AA-NAT. In rodent species, Aa-nat gene transcription is turned off during the daytime and markedly activated at night. In primates, sheep, and cows, the Aa-nat gene is constitutively transcripted with no visible daily variations. This inter-species difference in Aa-nat gene regulation leads to different daily profiles in melatonin synthesis and release. Thus, the nighttime onset of the rise in circulating melatonin is delayed and slow in rodents, whereas it is fast and sharp in sheep. In the camel (Camelus dromedarius), we have observed that circulating melatonin rises immediately after sunset, suggesting AA-NAT activity is regulated at the post-transcriptional level. In agreement with this hypothesis, we report herein the amount of Aa-nat mRNA in the camel pineal gland is high, during both the day and night with no daily variations, while melatonin concentration in the same pineal tissue is five times higher during the night than daytime.

  20. MurAA Is Required for Intrinsic Cephalosporin Resistance of Enterococcus faecalis

    PubMed Central

    Vesić, Dušanka

    2012-01-01

    Enterococcus faecalis is a low-GC Gram-positive bacterium that is intrinsically resistant to cephalosporins, antibiotics that target cell wall biosynthesis. To probe the mechanistic basis for intrinsic resistance, a library of transposon mutants was screened to identify E. faecalis strains that are highly susceptible to ceftriaxone, revealing a transposon mutant with a disruption in murAA. murAA is predicted to encode a UDP-N-acetylglucosamine 1-carboxyvinyl transferase that catalyzes the first committed step in peptidoglycan synthesis: phosphoenolpyruvate (PEP)-dependent conversion of UDP-N-acetylglucosamine to UDP-N-acetylglucosamine-enolpyruvate. In-frame deletion of murAA, but not its homolog in the E. faecalis genome (murAB), led to increased susceptibility of E. faecalis to cephalosporins. Furthermore, expression of murAA enhanced cephalosporin resistance in an E. faecalis mutant lacking IreK (formerly PrkC), a key kinase required for cephalosporin resistance. Further genetic analysis revealed that MurAA catalytic activity is necessary but not sufficient for this role. Collectively, our data indicate that MurAA and MurAB have distinct roles in E. faecalis physiology and suggest that MurAA possesses a unique property or activity that enables it to enhance intrinsic resistance of E. faecalis to cephalosporins. PMID:22290954

  1. Cyp2aa9 regulates haematopoietic stem cell development in zebrafish

    PubMed Central

    Chen, Jingying; He, Jianbo; Li, Li; Yang, Deqin; Luo, Lingfei

    2016-01-01

    Definitive haematopoiesis occurs during the lifetime of an individual, which continuously replenishes all blood and immune cells. During embryonic development, haematopoietic stem cell (HSC) formation is tightly controlled by growth factors, signalling molecules and transcription factors. But little is known about roles of the cytochrome P450 (CYP) 2 family member in the haematopoiesis. Here we report characterization and functional studies of Cyp2aa9, a novel zebrafish Cyp2 family member. And demonstrate that the cyp2aa9 is required for the HSC formation and homeostasis. Knockdown of cyp2aa9 by antisense morpholino oligos resulted the definitive HSC development is defective and the Wnt/β-catenin activity becomes reduced. The impaired HSC formation caused by cyp2aa9 morpholino can be rescued by administration of PGE2 through the cAMP/PKA pathway. Furthermore, the in vivo PGE2 level decreases in the cyp2aa9 morphants, and none of the PGE2 precursors is able to rescue phenotypes in the Cyp2aa9-deficient embryos. Taken together, these data indicate that Cyp2aa9 is functional in the step of PGE2 synthesis from PGH2, thus promoting Wnt activation and definitive HSC development. PMID:27197559

  2. Proteomic analysis of Cry2Aa-binding proteins and their receptor function in Spodoptera exigua

    PubMed Central

    Qiu, Lin; Zhang, Boyao; Liu, Lang; Ma, Weihua; Wang, Xiaoping; Lei, Chaoliang; Chen, Lizhen

    2017-01-01

    The bacterium Bacillus thuringiensis produces Crystal (Cry) proteins that are toxic to a diverse range of insects. Transgenic crops that produce Bt Cry proteins are grown worldwide because of their improved resistance to insect pests. Although Bt “pyramid” cotton that produces both Cry1A and Cry2A is predicted to be more resistant to several lepidopteran pests, including Spodoptera exigua, than plants that produce Cry1Ac alone, the mechanisms responsible for the toxicity of Cry2Aa in S. exigua are not well understood. We identified several proteins that bind Cry2Aa (polycalin, V-ATPase subunits A and B, actin, 4-hydroxybutyrate CoA-transferase [4-HB-CoAT]), and a receptor for activated protein kinase C (Rack), in S. exigua. Recombinant, expressed versions of these proteins were able to bind the Cry2Aa toxin in vitro assays. RNA interference gene knockdown of the Se-V-ATPase subunit B significantly decreased the susceptibility of S. exigua larvae to Cry2Aa, whereas knockdown of the other putative binding proteins did not. Moreover, an in vitro homologous competition assay demonstrated that the Se-V-ATPase subunit B binds specifically to the Cry2Aa toxin, suggesting that this protein acts as a functional receptor of Cry2Aa in S. exigua. This the first Cry2Aa toxin receptor identified in S. exigua brush-border membrane vesicles. PMID:28067269

  3. Bacillus thuringiensis Cyt2Aa2 toxin disrupts cell membranes by forming large protein aggregates

    PubMed Central

    Tharad, Sudarat; Toca-Herrera, José L.; Promdonkoy, Boonhiang; Krittanai, Chartchai

    2016-01-01

    Bacillus thuringiensis (Bt) Cyt2Aa2 showed toxicity against Dipteran insect larvae and in vitro lysis activity on several cells. It has potential applications in the biological control of insect larvae. Although pore-forming and/or detergent-like mechanisms were proposed, the mechanism underlying cytolytic activity remains unclear. Analysis of the haemolytic activity of Cyt2Aa2 with osmotic stabilizers revealed partial toxin inhibition, suggesting a distinctive mechanism from the putative pore formation model. Membrane permeability was studied using fluorescent dye entrapped in large unilamellar vesicles (LUVs) at various protein/lipid molar ratios. Binding of Cyt2Aa2 monomer to the lipid membrane did not disturb membrane integrity until the critical protein/lipid molar ratio was reached, when Cyt2Aa2 complexes and cytolytic activity were detected. The complexes are large aggregates that appeared as a ladder when separated by agarose gel electrophoresis. Interaction of Cyt2Aa2 with Aedes albopictus cells was investigated by confocal microscopy and total internal reflection fluorescent microscopy (TIRF). The results showed that Cyt2Aa2 binds on the cell membrane at an early stage without cell membrane disruption. Protein aggregation on the cell membrane was detected later which coincided with cell swelling. Cyt2Aa2 aggregations on supported lipid bilayers (SLBs) were visualized by AFM. The AFM topographic images revealed Cyt2Aa2 aggregates on the lipid bilayer at low protein concentration and subsequently disrupts the lipid bilayer by forming a lesion as the protein concentration increased. These results supported the mechanism whereby Cyt2Aa2 binds and aggregates on the lipid membrane leading to the formation of non-specific hole and disruption of the cell membrane. PMID:27612497

  4. The photometric variability of ζ Ori Aa observed by BRITE* **

    NASA Astrophysics Data System (ADS)

    Buysschaert, B.; Neiner, C.

    2016-12-01

    Using BRITE photometry, we investigated the photometric variability of the magnetic O-type supergiant ζOri Aa. We found two independent frequencies, leading to several higher harmonics and simple linear combinations. One frequency is related to the rotation period, f_{rot} = 0.15±0.02 d^{-1}. The derived rotation period from this frequency and its higher harmonics, P_{rot} = 6.65±0.28 d, is compatible with the literature value (P_{rot} = 6.83±0.08 d). Thanks to simultaneous CHIRON spectroscopy, we locate the origin of the second frequency, f_{env} = 0.10±0.02 d^{-1}, at the circumstellar environment. We propose mass-loss events as the underlying origin.

  5. AAS, growth hormone, and insulin abuse: psychological and neuroendocrine effects

    PubMed Central

    Graham, Michael R; Evans, Peter; Davies, Bruce; Baker, Julien S

    2008-01-01

    The nontherapeutic use of prescription medicines by individuals involved in sport is increasing. Anabolic-androgenic steroids (AAS) are the most widely abused drug. Much of our knowledge of the psychological and physiological effects of human growth hormone (hGH) and insulin has been learned from deficiency states. As a consequence of the Internet revolution, previously unobtainable and expensive designer drugs, particularly recombinant human growth hormone (rhGH) and insulin, have become freely available at ridiculously discounted prices from countries such as China and are being abused. These drugs have various physiological and psychological effects and medical personnel must become aware that such prescription medicine abuse appears to be used not only for performance and cosmetic reasons, but as a consequence of psychological pre-morbidity. PMID:18827854

  6. FRICTION-STIR-LAP-WELDS OF AA6111 ALUMINUM ALLOY

    SciTech Connect

    Yadava, Manasij; Mishra, Rajiv S.; Chen, Y. L.; Gayden, X.; Grant, Glenn J.

    2007-01-09

    Lap joints of 1 mm thick AA6111 aluminum sheets were made by friction stir welding, using robotic and conventional machines. Welds were made for advancing as well as retreating side loading. Thinning in welds was quantified. Lap shear test of welds was conducted in as-welded and paint-baked conditions. Conventional machine welds showed less thinning and better strength than robotic machine welds. Process forces in conventional machine welding were higher. Paint bake treatment improved the weld strength; but the improvement varied with process parameters. Advancing side loaded welds achieved higher strength than the retreating side loaded welds. Fracture location was found to occur on the loaded side of the weld and along the thinning defect.

  7. A profile of Keith AA Fox, cardiologist and researcher.

    PubMed

    Fox, Keith A A; Telfer, Caroline

    2014-01-01

    Professor Keith AA Fox speaks to Caroline Telfer, Commissioning Editor. Professor Keith AA Fox is the British Heart Foundation and the Duke of Edinburgh Professor of Cardiology at the University of Edinburgh (UK). He is a founding fellow of the European Society of Cardiology and is currently Chair of the Programme of the European Society of Cardiology. In addition, he was President of the British Cardiovascular Society from 2009 to 2012. Professor Fox gave the State-of-the-Art lecture on acute coronary syndromes at the American Heart Association, as well as the 2009 Plenary lecture at the European Society of Cardiology-American College of Cardiology Symposium, the Lord Rayner lecture of the Royal College of Physicians (London, UK) and the Sir Stanley Davidson Lecture of the Royal College (Edinburgh, UK). He was awarded the Silver Medal of the European Society of Cardiology in 2010. Professor Fox's major research interest lies in the mechanisms and manifestations of acute coronary arterial disease; his work extends from underlying biological mechanisms to in vitro and in vivo studies and clinical trials. He is the author of more than 587 scientific papers (H-index Web of Science 73, Citations: 30,261 to March 2013). Professor Fox is chairman of the RITA program, co-chairman of ROCKET-AF and OASIS program, and chair of the GRACE program (the largest multinational study in acute coronary syndromes), and a lead investigator for studies on novel antithrombins, anticoagulants and antiplatelets. He is an International Associate Editor of the European Heart Journal and a member of the editorial boards of a number of journals. His current areas of research include the inhibition of coronary thrombosis and the role of platelets and inflammation in acute coronary syndromes.

  8. An Update on the AAS Astronomy Ambassadors Program

    NASA Astrophysics Data System (ADS)

    Fienberg, Richard T.; Gurton, S.; Fraknoi, A.; Prather, E. E.; Hurst, A.; Schatz, D. L.

    2013-06-01

    The American Astronomical Society, partnering with organizations active in science education and public outreach (EPO), has launched a series of professional-development workshops and a community of practice designed to help improve early-career astronomers’ ability to effectively communicate with students and the public. Called Astronomy Ambassadors, the program provides mentoring and training experiences for young astronomers, from advanced undergraduates to beginning faculty; it also provides access to resources and a network of contacts within the astronomy EPO community. By learning how to implement effective education and outreach strategies, Astronomy Ambassadors become better teachers, better presenters at meetings, and better representatives of our science to the public and to government. And because young astronomers are a more diverse group than those who currently do the majority of outreach, they help the astronomical community present a more multicultural and gender-balanced face to the public, enabling members of underserved groups to see themselves as scientists. Ambassadors are provided with a large library of outreach activities and materials that are suitable for a range of venues and audiences and that will grow with time. For much of this library we are using resources developed by organizations such as the Astronomical Society of the Pacific, the Pacific Science Center, and the Center for Astronomy Education for other outreach programs, though some resources have been created by one of us (AF) specifically for this program. The first Astronomy Ambassadors workshop was held at the 221st meeting of the AAS in January 2013 and served 30 young astronomers chosen from more than 75 applicants. Incorporating feedback from workshop participants and lessons learned from the reports they’ve submitted after conducting their own outreach events, we are now planning the second annual workshop to be held 4-5 January 2014 at the 223rd AAS meeting in

  9. Molecular cloning of the cytochrome aa3 gene from the archaeon (Archaebacterium) Halobacterium halobium.

    PubMed

    Denda, K; Fujiwara, T; Seki, M; Yoshida, M; Fukumori, Y; Yamanaka, T

    1991-11-27

    A novel aa3-type cytochrome oxidase from the extremely halophilic archaeon, Halobacterium halobium, differs significantly from those of other prokaryotic and eukaryotic cytochrome oxidases (Fujiwara, T., Fukumori, Y., and Yamanaka, T. (1989) J. Biochem. 105, 287-292). In the present study, we cloned and sequenced the gene which encodes the cytochrome aa3 by using the polymerase chain reaction methods. The deduced amino acid sequence of subunit I of H. halobium cytochrome aa3 was more similar to that of subunit I of the eukaryotic cytochrome (44%, maize mitochondria) than that of the cytochrome from other bacteria (36%, Paracoccus denitrificans). The consensus sequence in putative metal binding residues is well-conserved also in H. halobium cytochrome aa3.

  10. Vip3Aa induces apoptosis in cultured Spodoptera frugiperda (Sf9) cells.

    PubMed

    Jiang, Kun; Mei, Si-Qi; Wang, Ting-Ting; Pan, Jin-Hua; Chen, Yue-Hua; Cai, Jun

    2016-09-15

    The vegetative insecticidal proteins (Vip) secreted by many Bacillus thuringiensis strains during their vegetative growth stage are regarded as second generation insecticidal proteins, as they share no sequence or structural homology with known crystal insecticidal proteins (Cry) and have a broad insecticidal spectrum. Compared with insecticidal crystal proteins (ICPs), the insecticidal mechanisms of Vips have been little studied. Here we investigated the mechanism responsible for Vip3Aa toxicity in cultured insect cells. Using, flow cytometry analyzes, TUNEL staining and DNA fragmentation assays, we show that Vip3Aa can induce apoptosis in Spodoptera frugiperda (Sf9) cells and cause cells to arrest at the G2/M phase. We also show that Vip3Aa can disrupt mitochondrial membrane potential (ΔΨm), leading to the activation of Sf-caspase-1, suggesting that a mitochondrial mediated and caspase dependent pathway may be involved in Vip3Aa-induced apoptosis in Sf9 cells.

  11. Homocysteine induced cardiovascular events: a consequence of long term anabolic‐androgenic steroid (AAS) abuse

    PubMed Central

    Graham, M R; Grace, F M; Boobier, W; Hullin, D; Kicman, A; Cowan, D; Davies, B; Baker, J S

    2006-01-01

    Objectives The long term effects (>20 years) of anabolic‐androgenic steroid (AAS) use on plasma concentrations of homocysteine (HCY), folate, testosterone, sex hormone binding globulin (SHBG), free androgen index, urea, creatinine, haematocrit (HCT), vitamin B12, and urinary testosterone/epitestosterone (T/E) ratio, were examined in a cohort of self‐prescribing bodybuilders. Methods Subjects (n = 40) were divided into four distinct groups: (1) AAS users still using AAS (SU; n = 10); (2) AAS users abstinent from AAS administration for 3 months (SA; n = 10); (3) non‐drug using bodybuilding controls (BC; n = 10); and (4) sedentary male controls (SC; n = 10). Results HCY levels were significantly higher in SU compared with BC and SC (p<0.01), and with SA (p<0.05). Fat free mass was significantly higher in both groups of AAS users (p<0.01). Daily energy intake (kJ) and daily protein intake (g/day) were significantly higher in SU and SA (p<0.05) compared with BC and SC, but were unlikely to be responsible for the observed HCY increases. HCT concentrations were significantly higher in the SU group (p<0.01). A significant linear inverse relationship was observed in the SU group between SHBG and HCY (r = −0.828, p<0.01), indicating a possible influence of the sex hormones in determining HCY levels. Conclusions With mounting evidence linking AAS to adverse effects on some clotting factors, the significantly higher levels of HCY and HCT observed in the SU group suggest long term AAS users have increased risk of future thromboembolic events. PMID:16488899

  12. Enhanced morphine- and cocaine-induced behavioral sensitization in alcohol-preferring AA rats.

    PubMed

    Honkanen, A; Mikkola, J; Korpi, E R; Hyytiä, P; Seppälä, T; Ahtee, L

    1999-03-01

    Locomotor stimulation and behavioral sensitization induced by acute and repeated treatment with alcohol, cocaine or morphine were studied in the alcohol-preferring AA (Alko, Alcohol), alcohol-avoiding ANA (Alko, Non-Alcohol) rats and non-selected Wistar rats. Daily treatment with alcohol (ethanol, 0.4 or 1.0 g/kg, IP) for 6 days had no effect on locomotor activity either in the AA or ANA rats. Acute cocaine (5, 10 or 20 mg/kg, IP) produced a locomotor stimulation in the animals of all lines studied, and there was no difference in this effect between the AA and ANA rats. During a 4-day repeated cocaine treatment, the AA rats became sensitized with the 10 mg/kg dose, while the ANA rats did not show any sensitization with this dose. With the 20 mg/kg cocaine dose, in addition to locomotor stimulation, the rats of all lines studied showed stereotyped behavior, which response was enhanced during repeated treatment. Morphine-induced locomotor stimulation was larger in the AA rats than in the ANA or Wistar rats both with 1.0 and 3.0 mg/kg doses and only the AA rats were sensitized during 4-day treatment with the 1 mg/kg dose. With the 3.0 mg/kg morphine dose, only the AA rats showed a weak sensitization evident only during the initial 30 min after morphine injection. As the drug-induced behavioral sensitization is an important factor in the development of drug addiction, it is possible that mechanisms underlying the enhanced susceptibility of the AA rats to morphine- and cocaine-induced sensitization contribute to the high intake of alcohol and other abused drugs by these animals.

  13. Modeling of AA5083 Material-Microstructure Evolution During Butt Friction-Stir Welding

    DTIC Science & Technology

    2010-07-01

    FSW behavior of a prototypical solution-strengthened and strain-hardened aluminum alloy, AA5083-H131, is modeled using a fully coupled thermo...is followed by a computational investigation in which FSW behavior of a prototypical solution-strengthened and strain-hardened aluminum alloy, AA5083...provided. This is followed by a computational investigation in which FSW behavior of a prototypical solution-strengthened and strain-hardened aluminum

  14. Insecticidal Activity and Histopathological Effects of Vip3Aa Protein from Bacillus thuringiensis on Spodoptera litura.

    PubMed

    Song, Feifei; Lin, Yunfeng; Chen, Chen; Shao, Ensi; Guan, Xiong; Huang, Zhipeng

    2016-10-28

    Vegetative insecticidal proteins (Vips) are insecticidal proteins synthesized by Bacillus thuringiensis during the vegetative stage of growth. In this study, Vip3Aa protein, obtained by in vitro expression of the vip3Aa gene from B. thuringiensis WB5, displayed high insecticidal activity against Spodoptera litura aside from Spodoptera exigua and Helicoverpa armigera. Bioassay results showed that the toxicity of Vip3Aa protein against S. litura larvae statistically decreased along with the increase of the age of the larvae, with LC50 = 2.609 ng/cm(2) for neonatal larvae, LC50 = 28.778 ng/cm(2) for first instar larvae, LC50 = 70.460 ng/cm(2) for second instar larvae, and LC50 = 200.627 ng/cm(2) for third instar larvae. The accumulative mortality of 100% larvae appeared at 72 h for all instars of S. litura larvae, when feeding respectively with 83.22, 213.04, 341.40, and 613.20 ng/cm(2) of Vip3Aa toxin to the neonatal and first to third instar larvae. The histopathological effects of Vip3Aa toxin on the midgut epithelial cells of S. litura larvae was also investigated. The TEM observations showed wide damage of the epithelial cell in the midgut of S. litura larvae fed with Vip3Aa toxin.

  15. The 9aaTAD Is Exclusive Activation Domain in Gal4

    PubMed Central

    Havelka, Marek; Rezacova, Martina

    2017-01-01

    The Gal4 protein is a well-known prototypic acidic activator that has multiple activation domains. We have previously identified a new activation domain called the nine amino acid transactivation domain (9aaTAD) in Gal4 protein. The family of the 9aaTAD activators currently comprises over 40 members including p53, MLL, E2A and other members of the Gal4 family; Oaf1, Pip2, Pdr1 and Pdr3. In this study, we revised function of all reported Gal4 activation domains. Surprisingly, we found that beside of the activation domain 9aaTAD none of the previously reported activation domains had considerable transactivation potential and were not involved in the activation of transcription. Our results demonstrated that the 9aaTAD domain is the only decisive activation domain in the Gal4 protein. We found that the artificial peptides included in the original Gal4 constructs were results of an unintended consequence of cloning that were responsible for the artificial transcriptional activity. Importantly, the activation domain 9aaTAD, which is the exclusive activation domain in Gal4, is also the central part of a conserved sequence recognized by the inhibitory protein Gal80. We propose a revision of the Gal4 regulation, in which the activation domain 9aaTAD is directly linked to both activation function and Gal80 mediated inhibition. PMID:28056036

  16. [Exposure degree of important non-target arthropods to Cry2Aa in Bt rice fields].

    PubMed

    Zhang, Qing-Ling; Li, Yun-He; Hua, Hong-Xia; Yang, Chang-Ju; Wu, Hong-Jin; Peng, Yu-Fa

    2013-06-01

    Based on the principle of "risk = hazard x exposure", the selected representative nontarget organisms in the assessment of the potential effects of insect-resistant genetically modified (GM) crops on non-target arthropods in laboratory are generally the arthropod species highly exposed to the insecticidal proteins expressed by the GM crops in farmland ecosystem. In order to understand the exposure degree of the important arthropod species to Cry proteins in Bt rice fields, and to select the appropriate non-target arthropods in the risk assessment of insect-resistant GM crops, the enzyme-linked immunosorbent assay (ELISA) was conducted to measure the Cry2Aa protein concentration in the arthropods collected from the cry2Aa rice fields at different rice growth stages. The results showed that there was a significant difference in the Cry2Aa content protein concentration in different arthropod species. Some species did not contain Cry2Aa protein, while some species contained larger amounts of Cry2Aa protein. Relative to the arthropods colleted after rice anthesis, the arthropods colleted in rice anthesis contained relative higher concentrations of Cry2Aa protein, especially for the predacious arthropods. No Cry proteins were detected in parasitic arthropods. This study provided references for the laboratory assessment of the effects of GM rice on nontarget arthropods.

  17. Presence of bacteriophage Aa phi 23 correlates with the population genetic structure of Actinobacillus actinomycetemcomitans.

    PubMed

    Haubek, D; Willi, K; Poulsen, K; Meyer, J; Kilian, M

    1997-02-01

    Several bacteriophages associated with the oral bacterium Actinobacillus actinomycetemcomitans have been identified. Lysogeny might affect the virulence of this bacterium, which has been implicated in the etiology of juvenile and adult periodontitis. We have determined the presence of bacteriophage Aa phi 23-related DNA sequences among 185 A. actinomycetemcomitans strains belonging to 2 well-characterized collections and have related the findings to the population genetic structure of the collections. 2 cloned Aa phi 23-specific DNA probes were used in Southern blot hybridization experiments to detect homologous sequences in whole-cell DNA of the strains. DNA from 65 (35%) of the 185 strains hybridized to either of the DNA probes. The majority (74%) of the hybridizing strains showed an identical hybridization pattern, indicating presence of phage Aa phi 23. Whole-cell DNA from the remaining hybridizing strains hybridized to the probes with different patterns, indicating that DNA sequences related to but different from phage Aa phi 23 occur in these strains. The majority (81%) of the strains which harbored phage Aa phi 23 were of serotype a, whereas serotype d strains appeared to be resistant to infection with this phage. There was a clear correlation between hybridization patterns and genetic subdivisions based on our previous population genetic analyses of A. actinomycetemcomitans. However, there was no significant correlation between occurrence of Aa phi 23 among A. actinomycetemcomitans strains and the periodontal status of the patients from whom the isolates were obtained, suggesting that this bacteriophage does not significantly influence the virulence of A. actinomycetemcomitans.

  18. Multiple Dirac particles in AA-stacked graphite and multilayers of graphene

    NASA Astrophysics Data System (ADS)

    Lobato, I.; Partoens, B.

    2011-04-01

    Using the tight-binding formalism we show that in the recently experimentally realized AA-stacked graphite in essence two types of massless relativistic Dirac particles are present with a different effective speed of light. We also investigate how the electronic structure evolves from a single graphene sheet into AA-stacked graphite. It is shown that in contrast to AB-stacked graphene layers, the spectrum of AA-stacked graphene layers can be considered as a superposition of single-layer spectra and only particles with a linear spectrum at the Fermi energy around the K point are present. From the evolution of the band overlap we show that 6 multilayers of AA-stacked graphene already behave as AA-stacked graphite. The evolution of the effective speeds of light of the Dirac particles to their bulk values shows exactly the same behavior. The tight-binding parameters we use to describe AA-stacked graphite and multilayers of graphene are obtained by ab initio calculations.

  19. Doping with anabolic androgenic steroids (AAS): Adverse effects on non-reproductive organs and functions.

    PubMed

    Nieschlag, Eberhard; Vorona, Elena

    2015-09-01

    Since the 1970s anabolic androgenic steroids (AAS) have been abused at ever increasing rates in competitive athletics, in recreational sports and in bodybuilding. Exceedingly high doses are often consumed over long periods, in particular by bodybuilders, causing acute or chronic adverse side effects frequently complicated by additional polypharmacy. This review summarizes side effects on non-reproductive organs and functions; effects on male and female reproduction have been recently reviewed in a parallel paper. Among the most striking AAS side effects are increases in haematocrit and coagulation causing thromboembolism, intracardiac thrombosis and stroke as well as other cardiac disturbances including arrhythmias, cardiomyopathies and possibly sudden death. 17α-alkylated AAS are liver toxic leading to cholestasis, peliosis, adenomas and carcinomas. Hyperbilirubinaemia can cause cholemic nephrosis and kidney failure. AAS abuse may induce exaggerated self-confidence, reckless behavior, aggressiveness and psychotic symptoms. AAS withdrawal may be accompanied by depression and suicidal intentions. Since AAS abuse is not or only reluctantly admitted physicians should be aware of the multitude of serious side effects when confronted with unclear symptoms.

  20. AA-PMe, a novel asiatic acid derivative, induces apoptosis and suppresses proliferation, migration, and invasion of gastric cancer cells.

    PubMed

    Jing, Yue; Wang, Gang; Ge, Ying; Xu, Minjie; Tang, Shuainan; Gong, Zhunan

    2016-01-01

    Asiatic acid (AA; 2α,3β,23-trihydroxyurs-12-ene-28-oic acid) is widely used for medicinal purposes in many Asian countries due to its various bioactivities. A series of AA derivatives has been synthesized in attempts to improve its therapeutic potencies. Herein we investigated the anti-tumor activities of N-(2α,3β,23-acetoxyurs-12-en-28-oyl)-l-proline methyl ester (AA-PMe), a novel AA derivative. AA-PMe exhibited a stronger anti-cancer activity than its parent compound AA. AA-PMe inhibited the proliferation of SGC7901 and HGC27 human gastric cancer cells in a dose-dependent manner but had no significant toxicity in human gastric mucosa epithelial cells (GES-1). AA-PMe induced cell cycle arrest in G0/G1 phase and blocked G1-S transition, which correlated well with marked decreases in levels of cyclin D1, cyclin-dependent kinase CKD4, and phosphorylated retinoblastoma protein, and increase in cyclin-dependent kinase inhibitor P15. Further, AA-PMe induced apoptosis of human gastric cancer cells by affecting Bcl-2, Bax, c-Myc, and caspase-3. Moreover, AA-PMe suppressed the migration and invasion of human gastric cancer cells (SGC7901 and HGC27) cells by downregulating the expression of MMP-2 and MMP-9. Overall, this study investigated the potential anti-cancer activities of AA-PMe including inducing apoptosis and suppressing proliferation, migration and invasion of gastric cancer cells, as well as the underlying mechanisms, suggesting that AA-PMe is a promising anti-cancer drug candidate in gastric cancer therapy.

  1. AA-PMe, a novel asiatic acid derivative, induces apoptosis and suppresses proliferation, migration, and invasion of gastric cancer cells

    PubMed Central

    Jing, Yue; Wang, Gang; Ge, Ying; Xu, Minjie; Tang, Shuainan; Gong, Zhunan

    2016-01-01

    Asiatic acid (AA; 2α,3β,23-trihydroxyurs-12-ene-28-oic acid) is widely used for medicinal purposes in many Asian countries due to its various bioactivities. A series of AA derivatives has been synthesized in attempts to improve its therapeutic potencies. Herein we investigated the anti-tumor activities of N-(2α,3β,23-acetoxyurs-12-en-28-oyl)-l-proline methyl ester (AA-PMe), a novel AA derivative. AA-PMe exhibited a stronger anti-cancer activity than its parent compound AA. AA-PMe inhibited the proliferation of SGC7901 and HGC27 human gastric cancer cells in a dose-dependent manner but had no significant toxicity in human gastric mucosa epithelial cells (GES-1). AA-PMe induced cell cycle arrest in G0/G1 phase and blocked G1-S transition, which correlated well with marked decreases in levels of cyclin D1, cyclin-dependent kinase CKD4, and phosphorylated retinoblastoma protein, and increase in cyclin-dependent kinase inhibitor P15. Further, AA-PMe induced apoptosis of human gastric cancer cells by affecting Bcl-2, Bax, c-Myc, and caspase-3. Moreover, AA-PMe suppressed the migration and invasion of human gastric cancer cells (SGC7901 and HGC27) cells by downregulating the expression of MMP-2 and MMP-9. Overall, this study investigated the potential anti-cancer activities of AA-PMe including inducing apoptosis and suppressing proliferation, migration and invasion of gastric cancer cells, as well as the underlying mechanisms, suggesting that AA-PMe is a promising anti-cancer drug candidate in gastric cancer therapy. PMID:27073325

  2. Multifunctional cellulolytic auxiliary activity protein HcAA10-2 from Hahella chejuensis enhances enzymatic hydrolysis of crystalline cellulose.

    PubMed

    Ghatge, Sunil S; Telke, Amar A; Waghmode, Tatoba R; Lee, Yuno; Lee, Keun-Woo; Oh, Doo-Byoung; Shin, Hyun-Dong; Kim, Seon-Won

    2015-04-01

    The modular auxiliary activity (AA) family of proteins is believed to cause amorphogenesis in addition to oxidative cleavage of crystalline cellulose although the supporting evidence is limited. HcAA10-2 is a modular AA10 family protein (58 kDa) composed of a AA10 module and a family two carbohydrate binding module (CBM2), joined by a long stretch of 222 amino acids of unknown function. The protein was expressed in Escherichia coli and purified to homogeneity. Scanning electron microscopy and X-ray diffraction analysis of Avicel treated with HcAA10-2 provided evidence for the disruption of the cellulose microfibrils ("amorphogenesis") and reduction of the crystallinity index, resulting in a twofold increase of cellulase adsorption on the polysaccharide surface. HcAA10-2 exhibited weak endoglucanase-like activity toward soluble cellulose and cello-oligosaccharides with an optimum at pH 6.5 and 45 °C. HcAA10-2 catalyzed oxidative cleavage of crystalline cellulose released native and oxidized cello-oligosaccharides in the presence of copper and an electron donor such as ascorbic acid. Multiple sequence alignment indicated that His1, His109, and Phe197 in the AA10 module formed the conserved copper-binding site. The reducing sugar released from Avicel by the endoglucanase Cel5 and Celluclast accompanying HcAA10-2 was increased by four- and sixfold, respectively. Moreover, HcAA10-2 and Celluclast acted synergistically on pretreated wheat straw biomass resulting in a threefold increase in reducing sugar than Celluclast alone. Taken together, these results suggest that HcAA10-2 is a novel multifunctional modular AA10 protein possessing amorphogenesis, weak endoglucanase, and oxidative cleavage activities useful for efficient degradation of crystalline cellulose.

  3. Determination of elements in ayurvedic medicinal plants by AAS

    NASA Astrophysics Data System (ADS)

    Teerthe, Santoshkumar S.; Kerur, B. R.

    2015-08-01

    India has a rich country for the uses of Ayurvedic medicinal plants for treatment and also the north- Karnataka boasts an unparallel diversity of medicinal plants. The present study attempts to estimate and compare the level of trace and heavy metals in some selected leaves and root samples of Ayurvedic medicinal plants such as Mg, Al, K, Cr, Mn, Fe, Cu, Zn, and Cd. The samples are collected from different places of North-Karnataka regions and sample solutions prepared as the ratio of 1:25:25+950ml=1000ppm.the trace and heavy elemental concentration was estimated using Atomic Absorption Spectrometric (AAS) Method. The average concentrations of Mg, Mn, Fe and Zn, are ranging from 2ppm to 5250.2ppm and potassium (K) has more concentration as compare to all other. The other elements likes Al, Cr, Cu, and Cd were also estimed and presented in the table. Therefore, these medicinal plants are rich in some essential minerals, especially K, Mg, Mn, Fe and Zn which are essential for human health

  4. Renal AA Amyloidosis in Patients with Type 2 Diabetes Mellitus

    PubMed Central

    Díez, Ramón; Madero, Magdalena; Gamba, Gerardo; Soriano, Juan; Soto, Virgilia

    2014-01-01

    Background Type 2 diabetes mellitus (T2DM) is the leading cause of chronic kidney disease and a major cause of cardiovascular disease (CVD) mortality. Inflammation is closely involved in the pathogenesis of T2DM, and reactive amyloidosis occurs in the presence of chronic inflammation. We hypothesized that patients with T2DM may have a higher prevalence of renal AA amyloidosis (RAAA) and that this could contribute to worse atherosclerosis and CVD. Materials and Methods We analyzed 330 autopsy kidneys from patients with a previous T2DM diagnosis. The kidney tissue was evaluated in order to determine the presence of diabetic nephropathy and RAAA, and systemic vessels were evaluated for the presence of atherosclerosis. Results RAAA was detected in 9% of our study population and was associated with an increased risk for nodular sclerosis [OR (95% CI)] [11 (2.04-59.16)], for chronic ischemic cardiomyopathy [4.59 (2.02-10.42)], for myocardial infarction [3.41 (1.52-7.64)] as well as for aortic [4.75 (1.09-20.69)], coronary [3.22 (1.47-7.04)], and intrarenal atherosclerosis [3.84 (1.46-10.09)]. Conclusions RAAA is prevalent in T2DM and is associated with worse CVD and renal disease, likely because RAAA is a marker of severe chronic inflammation. PMID:25337080

  5. Determination of elements in ayurvedic medicinal plants by AAS

    SciTech Connect

    Teerthe, Santoshkumar S.; Kerur, B. R.

    2015-08-28

    India has a rich country for the uses of Ayurvedic medicinal plants for treatment and also the north- Karnataka boasts an unparallel diversity of medicinal plants. The present study attempts to estimate and compare the level of trace and heavy metals in some selected leaves and root samples of Ayurvedic medicinal plants such as Mg, Al, K, Cr, Mn, Fe, Cu, Zn, and Cd. The samples are collected from different places of North-Karnataka regions and sample solutions prepared as the ratio of 1:25:25+950ml=1000ppm.the trace and heavy elemental concentration was estimated using Atomic Absorption Spectrometric (AAS) Method. The average concentrations of Mg, Mn, Fe and Zn, are ranging from 2ppm to 5250.2ppm and potassium (K) has more concentration as compare to all other. The other elements likes Al, Cr, Cu, and Cd were also estimed and presented in the table. Therefore, these medicinal plants are rich in some essential minerals, especially K, Mg, Mn, Fe and Zn which are essential for human health.

  6. Characterization of proteoglycans associated with mouse splenic AA amyloidosis.

    PubMed Central

    Stenstad, T; Magnus, J H; Husby, G

    1994-01-01

    We here report for the first time on the chemical characteristics of proteoglycans associated with mouse splenic reactive AA amyloid. Amyloid was induced in CBA/J mice by two different procedures; conventional casein treatment and by employing Freund's complete adjuvant, accelerated by Trypan Blue. Pulse-labelling was employed at distinct stages during amyloid development, followed by [35S]proteoglycan characterization of organ extracts. Repetitive 35S injections were also administered during the phase where amyloid deposition occurred most rapidly. Proteoglycans were extracted with guanidine in the presence of protease inhibitors and purified. The results showed that the production of proteoglycans is dramatically enhanced during amyloidogenesis, the glycosaminoglycan and proteoglycan accumulation being not only dependent on alterations in proteoglycan catabolism, but rather on increased synthesis. The increment could be demonstrated even at the stage before microscopic detection of amyloid deposits, clearly suggesting that the upregulation of proteoglycan expression precedes amyloid fibril formation. Two major proteoglycans were found to accumulate in advanced splenic amyloid; one a heparan sulphate proteoglycan of approx. 200 kDa with a core protein of 70 kDa, the other a chondroitin sulphate proteoglycan of smaller size. Moreover, free dermatan sulphate chains seemed to specifically accumulate in the organs during amyloid fibrillogenesis. We suggest that free glycosaminoglycans may be a specific feature of amyloidosis and that different proteoglycans and glycosaminoglycans play a role in formation and stabilization of amyloid fibrils in vivo. Images Figure 2 Figure 6 PMID:7980430

  7. Cylindrical diffractive lenses recorded on PVA/AA photopolymers

    NASA Astrophysics Data System (ADS)

    Fernández, R.; Gallego, S.; Márquez, A.; Navarro-Fuster, V.; Francés, J.; Neipp, C.; Beléndez, A.; Pascual, I.

    2016-04-01

    Photopolymers are optical recording materials appealing for many different applications such as holography, data storage, interconnectors, solar concentrations, or wave-guides fabrication. Recently the capacity of photopolymers to record diffractive optical elements (DOE's) has been investigated. Different authors have reported proposes to record DOE like fork gratings, photonics structures, lenses, sinusoidal, blazed or fork gratings. In these experiments there are different experimental set-ups and different photopolymers. In this work due to the improvement in the spatial light modulation technology together with the photopolymer science we propose a recording experimental system of DOE using a Liquid Cristal based on Silicon (LCoS) display as a master to store complex DOE like cylindrical lenses. This technology permits us an accurate control of the phase and the amplitude of the recording beam, with a very small pixel size. The main advantage of this display is that permit us to modify the DOE automatically, we use the software of the LCoS to send the voltage to each pixel In this work we use a photopolymer composed by acrylamide (AA) as polymerizable monomer and polyvinyl alcohol (PVA). We use a coverplated and index matched photopolymer to avoid the influence of the thickness variation on the transmitted light. In order to reproduce the material behaviour during polymerization, we have designed our model to simulate cylindrical lenses and used Fresnel propagation to simulate the light propagation through the DOE and analyze the focal plane and the properties of the recorded lenses.

  8. Fully Digital: Policy and Process Implications for the AAS

    NASA Astrophysics Data System (ADS)

    Biemesderfer, Chris

    Over the past two decades, every scholarly publisher has migrated at least the mechanical aspects of their journal publishing so that they utilize digital means. The academy was comfortable with that for a while, but publishers are under increasing pressure to adapt further. At the American Astronomical Society (AAS), we think that means bringing our publishing program to the point of being fully digital, by establishing procedures and policies that regard the digital objects of publication primarily. We have always thought about our electronic journals as databases of digital articles, from which we can publish and syndicate articles one at a time, and we must now put flesh on those bones by developing practices that are consistent with the realities of article at a time publication online. As a learned society that holds the long-term rights to the literature, we have actively taken responsibility for the preservation of the digital assets that constitute our journals, and in so doing we have not forsaken the legacy pre-digital assets. All of us who serve as the long-term stewards of scholarship must begin to evolve into fully digital publishers.

  9. Periodic barrier structure in AA-stacked bilayer graphene

    NASA Astrophysics Data System (ADS)

    Redouani, Ilham; Jellal, Ahmed

    2016-06-01

    We study the charge carriers transport in an AA-stacked bilayer graphene modulated by a lateral one-dimensional multibarrier structure. We investigate the band structures of our system, that is made up of two shifted Dirac cones, for finite and zero gap. We use the boundary conditions to explicitly determine the transmission probability of each individual cone (τ =+/- 1) for single, double and finite periodic barrier structure. We find that the Klein tunneling is only possible when the band structure is gapless and can occur at normal incidence as a result of the Dirac nature of the quasiparticles. We observe that the band structure of the barriers can have more than one Dirac points for finite periodic barrier. The resonance peaks appear in the transmission probability, which correspond to the positions of new cones index like associated with τ =+/- 1. Two conductance channels through different cones (τ =+/- 1) are found where the total conductance has been studied and compared to the cases of single layer and AB-stacked bilayer graphene.

  10. AA-stacked bilayer graphene quantum dots in magnetic field

    NASA Astrophysics Data System (ADS)

    Belouad, Abdelhadi; Zahidi, Youness; Jellal, Ahmed

    2016-05-01

    By applying the infinite-mass boundary condition, we analytically calculate the confined states and the corresponding wave functions of AA-stacked bilayer graphene (BLG) quantum dots (QDs) in the presence of an uniform magnetic field B. It is found that the energy spectrum shows two set of levels, which are the double copies of the energy spectrum for single layer graphene, shifted up-down by +γ and -γ , respectively. However, the obtained spectrum exhibits different symmetries between the electron and hole states as well as the intervalley symmetries. It is noticed that, the applied magnetic field breaks all symmetries, except one related to the intervalley electron-hole symmetry, i.e. {E}{{e}}(τ ,m)=-{E}{{h}}(τ ,m). Two different regimes of confinement are found: the first one is due to the infinite-mass barrier at weak B and the second is dominated by the magnetic field as long as B is large. We numerically investigated the basics features of the energy spectrum to show the main similarities and differences with respect to monolayer graphene, AB-stacked BLG and semiconductor QDs. Dedicated to Professor Dr Hachim A Yamani on the occasion of his 70th birthday.

  11. Cyt1Aa Protein of Bacillus thuringiensis Is Toxic to the Cottonwood Leaf Beetle, Chrysomela scripta, and Suppresses High Levels of Resistance to Cry3Aa

    PubMed Central

    Federici, Brian A.; Bauer, Leah S.

    1998-01-01

    The insecticidal activity of Bacillus thuringiensis is due primarily to Cry and Cyt proteins. Cry proteins are typically toxic to lepidopterous, coleopterous, or dipterous insects, whereas the known toxicity of Cyt proteins is limited to dipterans. We report here that a Cyt protein, Cyt1Aa, is also highly toxic to the cottonwood leaf beetle, Chrysomela scripta, with a median lethal concentration of 2.5 ng/mm2 of leaf surface for second-instar larvae. Additionally, we show that Cyt1Aa suppresses resistance to Cry3Aa greater than 5,000-fold in C. scripta, a level only partially overcome by Cry1Ba due to cross-resistance. Studies of the histopathology of C. scripta larvae treated with Cyt1Aa revealed disruption and sloughing of midgut epithelial cells, indicating that its mechanism of action against C. scripta is similar to that observed in mosquito and blackfly larvae. These novel properties suggest that Cyt proteins may have an even broader spectrum of activity against insects and, owing to their different mechanism of action in comparison to Cry proteins, might be useful in managing resistance to Cry3 and possibly other Cry toxins used in microbial insecticides and transgenic plants. PMID:9797292

  12. 40 CFR Appendix A to Subpart Aa of... - Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart AA

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... citation Requirement Applies tosubpart AA Comment 63.1(a)(1) through (4) General Applicability Yes. 63.1(a...) Alternative Test Method Yes. 63.7(g) Data Analysis Yes. 63.7(h) Waiver of Tests Yes. 63.8(a)(1)...

  13. Complete genome sequence of Bacillus thuringiensis tenebrionis 4AA1, a typical strain with toxicity to Coleopteran insects.

    PubMed

    Gao, Qiuling; Zheng, Jinshui; Zhu, Lei; Ruan, Lifang; Peng, Donghai; Sun, Ming

    2015-06-20

    Bacillus thuringiensis serovar morrisoni biovar tenebrionis has been developed as an bioinsecticide to control Coleopteran insects in agriculture and forestry for a few decades. Its major crystal protein Cry3Aa was also applied to transgenic crops. Here we report the complete genome sequence of strain tenebrionis 4AA1, which has one chromosome of 5,652,292bp and six plasmids. Two crystal protein genes, cry3Aa and cry15Aa, locate on one single plasmid named pBMB51. This strain also possesses plentiful virulence factors besides crystal proteins.

  14. Overview of AA and Research Progress: What Have We Learned and Where Are We Headed?

    PubMed

    Norris, David A

    2015-11-01

    During its 25th anniversary year, the National Alopecia Areata Foundation undertook a project to completely re-evaluate their research program and to help focus and direct future directions of alopecia areata research to better meet the goals of people with alopecia areata (AA) and the scientists working to discover mechanisms of disease and better treatments for AA. This project was embodied in four research summits in 2008, 2009, 2010, and 2012, as part of the Foundation's main strategic initiative, the Alopecia Areata Treatment Development Program to accelerate progress toward a viable alopecia areata treatment. The first summit was an evaluation of the progress of AA research in a global sense, with an emphasis on how to use the research programs to bring better treatments to patients. The second summit focused on immunology and how to better understand the autoimmune nature of AA. The third summit focused on developing a clinical research network that could most effectively bring new treatments to patients. The fourth summit consolidated the considerable evidence of the mechanisms of AA, and how these mechanisms could be targeted by modern therapies, many of which were being used effectively in other autoimmune diseases. These four summits laid the foundation for the fifth summit in the series: From Targets to Treatments: Bridging Autoimmune Research to Advance Understanding of Alopecia Areata.

  15. Mechanism of decay of the cry1Aa mRNA in Bacillus subtilis.

    PubMed Central

    Vázquez-Cruz, C; Olmedo-Alvarez, G

    1997-01-01

    We undertook the study of the decay process of the cry1Aa mRNA of Bacillus thuringiensis expressed in B. subtilis. The cry1Aa transcript is a 3.7-kb mRNA expressed during sporulation whose transcriptional control has previously been studied in both B. subtilis and B. thuringiensis. We found that the cry1Aa mRNA has a half-life of around 9 min and that its decay occurs through endoribonucleolytic cleavages which result in three groups of high-molecular-weight mRNA intermediates ranging in size from 2.7 to 0.5 kb. A comparative study carried out with Escherichia coli showed a similar pattern of degradation intermediates. Primer extension analysis carried out on RNA from B. subtilis revealed that most cleavages occur within two regions located toward the 5' and 3' ends of the mRNA. The most prominent processing site observed for the cry1Aa mRNA isolated from B. subtilis is only two bases away from that occurring on RNA isolated from E. coli. Most cleavage sites occur at seemingly single-stranded RNA segments rich in A and U nucleotides, suggesting that a common and conserved mechanism may process the cry1Aa mRNA. PMID:9335281

  16. The Impact of Reclassification from Division II to DI-AA and from Division I-AA to I-A on NCAA Member Institutions from 1993 to 2003

    ERIC Educational Resources Information Center

    Frieder, Laura L., Comp.; Fulks, Daniel L., Comp.

    2007-01-01

    Recent years have seen a number of National Collegiate Athletic Association (NCAA) Division II institutions seeking reclassification to Division I-AA and Division I-AA institutions moving to Division I-A. Yet, other schools that seem like natural candidates to reclassify have resisted. The purpose of this study is to investigate the impact of the…

  17. Generalized AA-amyloidosis in Siberian tigers (Panthera tigris altaica) with predominant renal medullary amyloid deposition.

    PubMed

    Schulze, C; Brügmann, M; Böer, M; Brandt, H P; Pohlenz, J; Linke, R P

    1998-01-01

    Generalized amyloidosis with predominant renal medullary amyloid deposition was found in four closely related Siberian tigers (Panthera tigris altaica) suffering from end stage kidney diseases. Only minimal to mild amounts of amyloid were deposited in various organs outside the kidneys with individually variable organ involvement. The Congo red staining affinity of amyloid deposits was sensitive to potassium permanganate oxidation. The deposits were further characterized as being of the amyloid-A (AA) type by immunohistochemistry using the mouse monoclonal antibody mc4 directed against a conserved region of the human AA-protein. A combination of immunohistochemistry and Congo red staining was much more sensitive for the diagnosis of amyloid deposits than Congo red staining alone. With this combination, even minimal amyloid deposits were detected that had been missed in the first reading using Congo-red-stained slides alone. Since no common primary cause was identified, the amyloidosis was classified as idiopathic generalized AA-amyloidosis with a potential familial predisposition.

  18. Novel strategy for protein production using a peptide tag derived from Bacillus thuringiensis Cry4Aa.

    PubMed

    Hayakawa, Tohru; Sato, Shinya; Iwamoto, Shigehisa; Sudo, Shigeo; Sakamoto, Yoshiki; Yamashita, Takaaki; Uchida, Motoaki; Matsushima, Kenji; Kashino, Yohko; Sakai, Hiroshi

    2010-07-01

    Numerous proteins cannot be sufficiently prepared by ordinary recombinant DNA techniques because they are unstable or have deleterious effects on the host cell. One idea to prepare such proteins is to produce them as protein inclusions. Here we developed a novel system to effectively prepare proteins by using peptide tags derived from the insecticidal Cry toxin of a soil bacterium, Bacillus thuringiensis. Fusion with this peptide tag, designated 4AaCter, facilitates the formation of protein inclusions of glutathione S-transferase in Escherichia coli without losing the enzyme activity. Application of 4AaCter to the production of syphilis antigens TpN15, TpN17 and TpN47 from Treponema pallidum yielded excellent results, including a dramatic increase in the production level, simplification of the product purification and high reactivity with syphilis antibody. The use of 4AaCter may provide an innovational strategy for the efficient production of proteins.

  19. An Essential Role for Senescent Cells in Optimal Wound Healing through Secretion of PDGF-AA

    PubMed Central

    Demaria, Marco; Ohtani, Naoko; Youssef, Sameh A.; Rodier, Francis; Toussaint, Wendy; Mitchell, James R.; Laberge, Remi-Martin; Vijg, Jan; Van Steeg, Harry; Dollé, Martijn E.T.; Hoeijmakers, Jan H.J.; de Bruin, Alain; Hara, Eiji; Campisi, Judith

    2015-01-01

    SUMMARY Cellular senescence suppresses cancer by halting the growth of premalignant cells, yet the accumulation of senescent cells is thought to drive age-related pathology through a senescence-associated secretory phenotype (SASP), the function of which is unclear. To understand the physiological role(s) of the complex senescent phenotype, we generated a mouse model in which senescent cells can be visualized and eliminated in living animals. We show that senescent fibroblasts and endothelial cells appear very early in response to a cutaneous wound, where they accelerate wound closure by inducing myofibroblast differentiation through the secretion of platelet-derived growth factor AA (PDGF-AA). In two mouse models, topical treatment of senescence-free wounds with recombinant PDGF-AA rescued the delayed wound closure and lack of myofibroblast differentiation. These findings define a beneficial role for the SASP in tissue repair and help to explain why the SASP evolved. PMID:25499914

  20. An essential role for senescent cells in optimal wound healing through secretion of PDGF-AA.

    PubMed

    Demaria, Marco; Ohtani, Naoko; Youssef, Sameh A; Rodier, Francis; Toussaint, Wendy; Mitchell, James R; Laberge, Remi-Martin; Vijg, Jan; Van Steeg, Harry; Dollé, Martijn E T; Hoeijmakers, Jan H J; de Bruin, Alain; Hara, Eiji; Campisi, Judith

    2014-12-22

    Cellular senescence suppresses cancer by halting the growth of premalignant cells, yet the accumulation of senescent cells is thought to drive age-related pathology through a senescence-associated secretory phenotype (SASP), the function of which is unclear. To understand the physiological role(s) of the complex senescent phenotype, we generated a mouse model in which senescent cells can be visualized and eliminated in living animals. We show that senescent fibroblasts and endothelial cells appear very early in response to a cutaneous wound, where they accelerate wound closure by inducing myofibroblast differentiation through the secretion of platelet-derived growth factor AA (PDGF-AA). In two mouse models, topical treatment of senescence-free wounds with recombinant PDGF-AA rescued the delayed wound closure and lack of myofibroblast differentiation. These findings define a beneficial role for the SASP in tissue repair and help to explain why the SASP evolved.

  1. Comparison of preliminary results from Airborne Aster Simulator (AAS) with TIMS data

    NASA Technical Reports Server (NTRS)

    Kannari, Yoshiaki; Mills, Franklin; Watanabe, Hiroshi; Ezaka, Teruya; Narita, Tatsuhiko; Chang, Sheng-Huei

    1992-01-01

    The Japanese Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER), being developed for a NASA EOS-A satellite, will have 3 VNIR, 6 SWIR, and 5 TIR (8-12 micron) bands. An Airborne ASTER Simulator (AAS) was developed for Japan Resources Observation System Organization (JAROS) by the Geophysical Environmental Research Group (GER) Corp. to research surface temperature and emission features in the MWIR/TIR, to simulate ASTER's TIR bands, and to study further possibility of MWIR/TIR bands. ASTER Simulator has 1 VNIR, 3 MWIR (3-5 microns), and 20 (currently 24) TIR bands. Data was collected over 3 sites - Cuprite, Nevada; Long Valley/Mono Lake, California; and Death Valley, California - with simultaneous ground truth measurements. Preliminary data collected by AAS for Cuprite, Nevada is presented and AAS data is compared with Thermal Infrared Multispectral Scanner (TIMS) data.

  2. AA479 antiserum: new reagent for the serotype characterization of atypical variants of Shigella flexneri.

    PubMed

    van der Ploeg, Claudia A; Rogé, Ariel D; Bordagorria, Ximena L; de Urquiza, María T; Viñas, María R; Pichel, Mariana G; Bruno, Susana B

    2015-01-01

    Shigella flexneri is divided into 13 serotypes based on the combination of antigenic determinants present in the O-antigen. A new O-antigen modification with phosphoethanolamine has been identified. The presence of this antigenic determinant (called E1037) is recognized by monoclonal antibody MASF IV-1. Given the increasing incidence of these new variants and the difficulty in supplying the monoclonal antibody to our country, we produced a polyclonal antiserum (AA479) through immunization with a S. flexneri Xv strain. The antiserum specificity was assessed by slide agglutination against isolates from clinical cases and a culture collection representing all Shigella serotypes. The results obtained demonstrated a 100% correlation between AA479 absorbed antiserum and monoclonal antibody MASF IV-1. The availability of AA479 antiserum in every public hospital in Argentina will allow us to identify atypical S. flexneri isolates in order to strengthen Shigella surveillance in our country and to compare with global epidemiological data.

  3. 32 CFR 1630.48 - Class 4-A-A: Registrant who has performed military service for a foreign nation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... military service for a foreign nation. 1630.48 Section 1630.48 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM CLASSIFICATION RULES § 1630.48 Class 4-A-A: Registrant who has performed military service for a foreign nation. In Class 4-A-A shall be placed any...

  4. Transcription factors may frame Aa-nat gene expression and melatonin synthesis at night in the Syrian hamster pineal gland.

    PubMed

    Garidou, Marie-Laure; Diaz, Elena; Calgari, Christiane; Pévet, Paul; Simonneaux, Valérie

    2003-06-01

    Pineal melatonin synthesis is stimulated at night following an increase in arylalkylamine-N-acetyltransferase (AA-NAT) activity. Depending on the species, two mechanisms of enzyme activation have been described: a cAMP/phospho-cAMP response element-binding protein-dependent stimulation of Aa-nat gene transcription in the rat, presumed to occur in all rodents, or a posttranslational regulation of AA-NAT protein in ongulates. The present data obtained in the Syrian hamster indicate another route of AA-NAT regulation. Elevated nocturnal levels of Aa-nat mRNA were strongly suppressed following light exposure or adrenergic antagonist administration, demonstrating the involvement of norepinephrine in the stimulation of melatonin synthesis. However, administration of adrenergic agonists during the day did not increase Aa-nat mRNA unless a protein synthesis inhibitor was given during the previous night. This indicates that an inhibitory protein, synthesized at night, prevents melatonin synthesis during the day. By contrast, a protein synthesis inhibitor given at the beginning of the night markedly reduced Aa-nat mRNA, suggesting that a stimulatory protein (transcription factor?) is necessary for Aa-nat gene transcription at night. Noteworthy, hamsters raised in long photoperiod were responsive to adrenergic agonist injection only in the first hour after light onset, a response that may be important in this photoperiodic species in which the melatonin peak extends into the morning hours in a short photoperiod.

  5. Participation and Performance Reporting for the Alternate Assessment Based on Modified Achievement Standards (AA-MAS). Technical Report 58

    ERIC Educational Resources Information Center

    Albus, Deb; Thurlow, Martha L.; Lazarus, Sheryl S.

    2011-01-01

    This report examines publicly reported participation and performance data for the alternate assessment based on modified achievement standards (AA-MAS). The authors' analysis of these data included all states publicly reporting AA-MAS data, regardless of whether they had received approval to use the results for Title I accountability calculations.…

  6. 76 FR 6794 - 30-Day Submission Period for Requests for ONC-Approved Accreditor (ONC-AA) Status

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-08

    ... HUMAN SERVICES 30-Day Submission Period for Requests for ONC-Approved Accreditor (ONC-AA) Status AGENCY... ONC-Approved Accreditor (ONC-AA) status. Authority: 42 U.S.C. 300jj-11. DATES: The 30-day submission... a notice in the Federal Register to announce the 30-day period during which requests for...

  7. States' Participation Guidelines for Alternate Assessments Based on Modified Academic Achievement Standards (AA-MAS) in 2009. Synthesis Report 75

    ERIC Educational Resources Information Center

    Lazarus, Sheryl S.; Hodgson, Jennifer; Thurlow, Martha L.

    2010-01-01

    All students, including students with disabilities, must be included in state accountability systems as required by law. In April 2007, federal regulations provided states the flexibility to offer another assessment option--an Alternate Assessment based on Modified Achievement Standards (AA-MAS) for some students with disabilities. The AA-MAS is…

  8. States' Participation Guidelines for Alternate Assessments Based on Modified Academic Achievement Standards (AA-MAS) in 2010. Synthesis Report 82

    ERIC Educational Resources Information Center

    Lazarus, Sheryl S.; Hodgson, Jennifer R.; Price, Lynn M.; Thurlow, Martha L.

    2011-01-01

    Federal legislation requires that all students participate in state accountability systems. Most students with disabilities participate in the regular assessment, with or without accommodations. Students with more significant cognitive disabilities participate in the Alternate Assessment based on Alternate Achievement Standards (AA-AAS). A few…

  9. Response of cyt a,a3 in the situ canine heart to transient ischemic episodes.

    PubMed

    Snow, T R; Kleinmann, L H; LaManna, J C; Wechsler, A S; Jöbsis, F F

    1981-01-01

    Experiments were performed to examine the response of cyt a,a3 to transient ischemic and hypoxic episodes in the empty, fibrillating canine heart in situ. Using a dual wavelength, differential spectrophotometer, reaction spectra show an absorption peak at approximately 605 nm consistent with that obtained from purified cyt a,a3. The characteristics of the averaged reaction spectrum in the interval 590 nm to 610 nm indicate that hemoglobin/myoglobin contribute no more than 23% to the signal measured at 605 nm. A regimen of one 30 sec global ischemia (GI) repeated once every 3 minutes over a 90 min period showed no appreciable signal deterioration. Therefore, five such interventions were subsequently used as the test perturbation. Studies of the effects of ischemic episodes of 30 and 60 min show that the response of cyt a,a3 to this test intervention was smaller (90 +/- 6% and 89 +/- 7%) than that observed prior to the ischemic episode. Changes in coronary perfusion pressure (+/- 10 Torr) produced an immediate oxidation/reduction of cyt a,a3. In the working heart, just prior to fibrillation, 6 sec to interrupted ventilation resulted in a continuous reduction of cyt a,a3. The data from these studies show: 1) The redox state of cyt a,a3 may be continuously monitored in the canine heart in situ. 2) Following ischemias of 30 and 60 min duration, respiratory chain function may be impaired; and 3) The well-perfused epicardium is extremely sensitive to small changes in oxygen delivery.

  10. The twelve-step recovery model of AA: a voluntary mutual help association.

    PubMed

    Borkman, Thomasina

    2008-01-01

    Alcoholism treatment has evolved to mean professionalized, scientifically based rehabilitation. Alcoholics Anonymous (AA) is not a treatment method; it is far better understood as a Twelve-Step Recovery Program within a voluntary self-help/mutual aid organization of self-defined alcoholics. The Twelve-Step Recovery Model is elaborated in three sections, patterned on the AA logo (a triangle within a circle): The triangle's legs represent recovery, service, and unity; the circle represents the reinforcing effect of the three legs upon each other as well as the "technology" of the sharing circle and the fellowship. The first leg of the triangle, recovery, refers to the journey of individuals to abstinence and a new "way of living." The second leg, service, refers to helping other alcoholics which also connects the participants into a fellowship. The third leg, unity, refers to the fellowship of recovering alcoholics, their groups, and organizations. The distinctive AA organizational structure of an inverted pyramid is one in which the members in autonomous local groups direct input to the national service bodies creating a democratic, egalitarian organization maximizing recovery. Analysts describe the AA recovery program as complex, implicitly grounded in sound psychological principles, and more sophisticated than is typically understood. AA provides a nonmedicalized and anonymous "way of living" in the community and should probably be referred to as the Twelve-Step/Twelve Tradition Recovery Model in order to clearly differentiate it from professionally based twelve-step treatments. There are additional self-help/mutual aid groups for alcoholics who prefer philosophies other than AA.

  11. DARPP-32 and Akt regulation in ethanol-preferring AA and ethanol-avoiding ANA rats.

    PubMed

    Nuutinen, Saara; Kiianmaa, Kalervo; Panula, Pertti

    2011-09-26

    Ethanol and other addictive drugs affect many intracellular phosphorylation and dephosphorylation cascades. These cascades are thought to be highly important in the regulation of neuronal activity. The present experiments characterized the regulation of three key signaling molecules, DARPP-32 (dopamine and cAMP regulated phosphoprotein, 32kDa), Akt kinase and ERK1/2 (extracellular signal-regulated kinase 1 and 2) in ethanol-preferring AA (Alko, alcohol) and ethanol-avoiding ANA (Alko, non-alcohol) rat lines. Radioactive in situ hybridization was used in drug naïve animals and Western blotting after acute ethanol administration in striatum, hippocampus and prefrontal cortex. The mRNA levels of DARPP-32 in striatal areas were higher in ANA rats than in AA rats. There was no difference in the striatal enriched phosphatase (STEP61), the downstream target of DARPP-32 expression between the rat lines. Ethanol (1.5g/kg) increased phosphorylation of DARPP-32 at threonine 34 in both AA and in ANA rats indicating that acute ethanol activates DARPP-32 similarly in these rat lines. The expression of Akt kinase was higher in the CA1 of hippocampus in ANA than in AA rats and acute ethanol activated Akt in hippocampus in ANA but not in AA rats. No significant alterations in the regulation of ERK1/2 were found in either rat line. Our findings suggest that DARPP-32 and Akt are regulated by ethanol and differences in the regulation of these molecules might contribute to the dramatically different ethanol drinking patterns seen in AA and ANA rats.

  12. ORBITAL AND PHYSICAL PROPERTIES OF THE σ Ori Aa, Ab, B TRIPLE SYSTEM

    SciTech Connect

    Simón-Díaz, S.; Caballero, J. A.; Apellániz, J. Maíz; Lorenzo, J.; Negueruela, I.; Dorda, R.; Marco, A.; Schneider, F. R. N.; Barbá, R. H.; Montes, D.; Pellerin, A.; Sanchez-Bermudez, J.; Sota, A.

    2015-02-01

    We provide a complete characterization of the astrophysical properties of the σ Ori Aa, Ab, B hierarchical triple system and an improved set of orbital parameters for the highly eccentric σ Ori Aa, Ab spectroscopic binary. We compiled a spectroscopic data set comprising 90 high-resolution spectra covering a total time span of 1963 days. We applied the Lehman-Filhés method for a detailed orbital analysis of the radial velocity curves and performed a combined quantitative spectroscopic analysis of the σ Ori Aa, Ab, B system by means of the stellar atmosphere code FASTWIND. We used our own plus other available information on photometry and distance to the system for measuring the radii, luminosities, and spectroscopic masses of the three components. We also inferred evolutionary masses and stellar ages using the Bayesian code BONNSAI. The orbital analysis of the new radial velocity curves led to a very accurate orbital solution of the σ Ori Aa, Ab pair. We provided indirect arguments indicating that σ Ori B is a fast-rotating early B dwarf. The FASTWIND+BONNSAI analysis showed that the Aa, Ab pair contains the hottest and most massive components of the triple system while σ Ori B is a bit cooler and less massive. The derived stellar ages of the inner pair are intriguingly younger than the one widely accepted for the σ Orionis cluster, at 3 ± 1 Ma. The outcome of this study will be of key importance for a precise determination of the distance to the σ Orionis cluster, the interpretation of the strong X-ray emission detected for σ Ori Aa, Ab, B, and the investigation of the formation and evolution of multiple massive stellar systems and substellar objects.

  13. Transgenic cotton expressing Cry10Aa toxin confers high resistance to the cotton boll weevil.

    PubMed

    Ribeiro, Thuanne Pires; Arraes, Fabricio Barbosa Monteiro; Lourenço-Tessutti, Isabela Tristan; Silva, Marilia Santos; Lisei-de-Sá, Maria Eugênia; Lucena, Wagner Alexandre; Macedo, Leonardo Lima Pepino; Lima, Janaina Nascimento; Santos Amorim, Regina Maria; Artico, Sinara; Alves-Ferreira, Márcio; Mattar Silva, Maria Cristina; Grossi-de-Sa, Maria Fatima

    2017-01-12

    Genetically modified (GM) cotton plants that effectively control cotton boll weevil (CBW), which is the most destructive cotton insect pest in South America, are reported here for the first time. This work presents the successful development of a new GM cotton with high resistance to CBW conferred by Cry10Aa toxin, a protein encoded by entomopathogenic Bacillus thuringiensis (Bt) gene. The plant transformation vector harbouring cry10Aa gene driven by the cotton ubiquitination-related promoter uceA1.7 was introduced into a Brazilian cotton cultivar by biolistic transformation. Quantitative PCR (qPCR) assays revealed high transcription levels of cry10Aa in both T0 GM cotton leaf and flower bud tissues. Southern blot and qPCR-based 2(-ΔΔCt) analyses revealed that T0 GM plants had either one or two transgene copies. Quantitative and qualitative analyses of Cry10Aa protein expression showed variable protein expression levels in both flower buds and leaves tissues of T0 GM cotton plants, ranging from approximately 3.0 to 14.0 μg g(-1) fresh tissue. CBW susceptibility bioassays, performed by feeding adults and larvae with T0 GM cotton leaves and flower buds, respectively, demonstrated a significant entomotoxic effect and a high level of CBW mortality (up to 100%). Molecular analysis revealed that transgene stability and entomotoxic effect to CBW were maintained in T1 generation as the Cry10Aa toxin expression levels remained high in both tissues, ranging from 4.05 to 19.57 μg g(-1) fresh tissue, and the CBW mortality rate remained around 100%. In conclusion, these Cry10Aa GM cotton plants represent a great advance in the control of the devastating CBW insect pest and can substantially impact cotton agribusiness.

  14. Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano, Hawaii: Field observations and key factors

    USGS Publications Warehouse

    Peterson, D.W.; Tilling, R.I.

    1980-01-01

    Nearly all Hawaiian basaltic lava erupts as pahoehoe, and some changes to aa during flowage and cooling; factors governing the transition involve certain critical relations between viscosity and rate of shear strain. If the lava slows, cools, and stops in direct response to concomitant increase in viscosity before these critical relations are reached, it remains pahoehoe. But, if flow mechanics (flow rate, flow dimensions, slope, momentum, etc.) impel the lava to continue to move and deform even after it has become highly viscous, the critical relations may be reached and the lava changes to aa. Typical modes of transition from pahoehoe to aa include: (1) spontaneous formation of relatively stiff clots in parts of the flowing lava where shear rate is highest; these clots grow into discrete, rough, sticky masses to which the remaining fluid lava incrementally adheres; (2) fragmentation and immersion of solid or semi-solid surface crusts of pahoehoe by roiling movements of the flow, forming cores of discrete, tacky masses; (3) sudden renewed movement of lava stored and cooled within surface reservoirs to form clots. The masses, fragments, and clots in these transition modes are characterized by spinose, granulated surfaces; as flow movement continues, the masses and fragments aggregate, fracture, and grind together, completing the transition to aa. Observations show that the critical relation between viscosity and rate of shear strain is inverse: if viscosity is low, a high rate of shear is required to begin the transition to aa; conversely, if viscosity is high, a much lower rate of shear will induce the transition. These relations can be demonstrated qualitatively with simple graphs, which can be used to examine the flow history of any selected finite lava element by tracing the path represented by its changing viscosity and shear rate. A broad, diffuse "transition threshold zone" in these graphs portrays the inverse critical relation between viscosity and shear

  15. Simulation on friction taper plug welding of AA6063-20Gr metal matrix composite

    NASA Astrophysics Data System (ADS)

    Hynes, N. Rajesh Jesudoss; Nithin, Abeyram M.

    2016-05-01

    Friction taper plug welding a variant of friction welding is useful in welding of similar and dissimilar materials. It could be used for joining of composites to metals in sophisticated aerospace applications. In the present work numerical simulation of friction taper plug welding process is carried out using finite element based software. Graphite reinforced AA6063 is modelled using the software ANSYS 15.0 and temperature distribution is predicted. Effect of friction time on temperature distribution is numerically investigated. When the friction time is increased to 30 seconds, the tapered part of plug gets detached and fills the hole in the AA6063 plate perfectly.

  16. Spectroscopic signatures of AA' and AB stacking of chemical vapor deposited bilayer MoS2

    DOE PAGES

    Xia, Ming; Li, Bo; Yin, Kuibo; ...

    2015-11-04

    We discuss prominent resonance Raman and photoluminescence spectroscopic differences between AA'and AB stacked bilayer molybdenum disulfide (MoS2) grown by chemical vapor deposition are reported. Bilayer MoS2 islands consisting of the two stacking orders were obtained under identical growth conditions. Also, resonance Raman and photoluminescence spectra of AA' and AB stacked bilayer MoS2 were obtained on Au nanopyramid surfaces under strong plasmon resonance. Both resonance Raman and photoluminescence spectra show distinct features indicating clear differences in interlayer interaction between these two phases. The implication of these findings on device applications based on spin and valley degrees of freedom.

  17. Safety and Abuse Testing of Energizer LiFeS2 AA Cells

    NASA Technical Reports Server (NTRS)

    Jeevarajan, Judith A.; Baldwin, Laura; Bragg, Bobby J.

    2003-01-01

    The LiFeS2 test program was part of the study on state-of-the-art batteries/cells available in the commercial market. It was carried out in an effort to replace alkaline AA cells for Shuttle and Station applications. A large number of alkaline cells are used for numerous Shuttle and Station applications as loose cells. Other government agencies reported good performance and abuse tolerance of the AA LiFeS2 cells. In this study, only abuse testing was performed on the cells to determine their tolerance. The tests carried out were over-discharge, external short circuit, heat-to-vent, vibration and drop.

  18. Constant amplitude and post-overload fatigue crack growth behavior in PM aluminum alloy AA 8009

    NASA Technical Reports Server (NTRS)

    Reynolds, A. P.

    1991-01-01

    A recently developed, rapidly solidified, powder metallurgy, dispersion strengthened aluminum alloy, AA 8009, was fatigue tested at room temperature in lab air. Constant amplitude/constant delta kappa and single spike overload conditions were examined. High fatigue crack growth rates and low crack closure levels compared to typical ingot metallurgy aluminum alloys were observed. It was proposed that minimal crack roughness, crack path deflection, and limited slip reversibility, resulting from ultra-fine microstructure, were responsible for the relatively poor da/dN-delta kappa performance of AA 8009 as compared to that of typical IM aluminum alloys.

  19. Alkaline phosphatases and aminopeptidases are altered in a Cry11Aa resistant strain of Aedes aegypti

    PubMed Central

    Lee, Su-Bum; Aimanova, Karlygash G.; Gill, Sarjeet S.

    2014-01-01

    Bacillus thuringiensis subsp. israelensis (Bti) has been widely for the biological control of mosquito populations. However, the mechanism of Bti toxins is still not fully understood. To further elucidate the mechanism of Bti toxins, we developed an Aedes aegypti resistant strain that shows high-level resistance to Cry11Aa toxin. After 27 selections with Cry11Aa toxin, the larvae showed a 124-fold resistance ratio for Cry11Aa (strain G30). G30 larvae showed cross-resistance to Cry4Aa (66-fold resistance), less to Cry4Ba (13-fold), but not to Cry11Ba (2-fold). Midguts from these resistant larvae did not show detectable difference in the processing of the Cry11Aa toxin compared to that in susceptible larvae (WT). Brush border membrane vesicles (BBMV) from resistant larvae bound slightly less Cry11Aa compared to WT BBMV. To identify potential proteins associated with Cry11A resistance, not only transcript changes in the larval midgut were analyzed using Illumina sequencing and qPCR, but alterations of previously identified receptor proteins were investigated using immunoblots. The transcripts of 375 genes were significantly increased and those of 208 genes were down regulated in the resistant larvae midgut compared to the WT. None of the transcripts for previously identified receptors of Cry11Aa (Aedes cadherin, ALP1, APN1, and APN2) were altered in these analyses. The genes for the identified functional receptors in resistant larvae midgut did not contain any mutation in their sequences nor was there any change in their transcript expression levels compared to WT. However, ALP proteins were expressed at reduced levels (~40%) in the resistant strain BBMV. APN proteins and their activity were also slightly reduced in resistance strain. The transcript levels of ALPs (AAEL013330 and AAEL015070) and APNs (AAEL008158, AAEL008162) were significantly reduced. These results strongly suggest that ALPs and APNs could be associated with Cry11Aa resistance in Ae. aegypti. PMID

  20. Expression of the Bacillus thuringiensis mosquitocidal toxin Cry11Aa in the aquatic bacterium Asticcacaulis excentricus.

    PubMed

    Armengol, Gemma; Guevara, Oscar Enrique; Orduz, Sergio; Crickmore, Neil

    2005-12-01

    A mosquitocidal aquatic bacterium has been developed by introducing an operon containing the cry11Aa, and p20 genes from Bacillus thuringiensis subsp. israelensis (Bti) into the gram-negative aquatic bacterium Asticcacaulis excentricus. After transformation, the cry11Aa gene was successfully expressed in recombinant A. excentricus under the tac promoter, at the level of 0.04 pg/cell. The recombinant bacteria were toxic to Aedes aegypti larvae with an LC(50) of 6.83 x 10(5) cells/mL. We believe that these bacteria may have potential as genetically engineered microorganisms for the control of mosquito larvae.

  1. Survey of Volatiles in the Disks Around GV Tau N and AA Tau

    NASA Astrophysics Data System (ADS)

    Gibb, Erika

    2010-02-01

    We propose to use NIRSPEC to characterize the gas phase volatiles, particularly organic molecules, in circumstellar disks toward Tauri stars GV Tau N and AA Tau. These sources have recently been found to exhibit rich molecular absorption (GV Tau N; Gibb et al. 2007) and emission (AA Tau; Carr et al. 2008) spectra that sample distinct regions of the circumstellar disk. If we are to understand the distribution of materials in disks and place our solar system in context, these systems must be studied in detail. As such, we propose to perform a near-infrared survey of these two sources.

  2. Multi-Response Optimization of Friction-Stir-Welded AA1100 Aluminum Alloy Joints

    NASA Astrophysics Data System (ADS)

    Rajakumar, S.; Balasubramanian, V.

    2012-06-01

    AA1100 aluminum alloy has gathered wide acceptance in the fabrication of light weight structures. Friction stir welding process (FSW) is an emerging solid state joining process in which the material that is being welded does not melt and recast. The process and tool parameters of FSW play a major role in deciding the joint characteristics. In this research, the relationships between the FSW parameters (rotational speed, welding speed, axial force, shoulder diameter, pin diameter, and tool hardness) and the responses (tensile strength, hardness, and corrosion rate) were established. The optimal welding conditions to maximize the tensile strength and minimize the corrosion rate were identified for AA1100 aluminum alloy and reported here.

  3. Electrochemical test for predicting microbiologically influenced corrosion of aluminum and AA 7005 alloy

    SciTech Connect

    Ayllon, E.S. ); Rosales, B.M. )

    1994-08-01

    The susceptibility of pure aluminum (Al) and Aluminum Association (AA) 7005 alloy (UNS A97005) to pitting by microbiologically influenced corrosion (MIC) in an integral jet fuel tank was determined through polarization measurements. Usually, the most corrosive reported species is the fungus Hormonconis resinae. The effect of its proliferation on pure Al and AA 7005-T6 alloy was studied through anodic and cathodic potentiodynamic polarization. The type and relative amount of corrosion damage to the metal were determined. Morphology of the attack was analyzed by scanning electron microscopy (SEM). Distribution of the alloying elements was determined using energy dispersive x-ray analysis (EDXA).

  4. [Comparison of texture distribution of cold rolled DC and CC AA 5052 aluminum alloy at different positions through thickness direction by XRD].

    PubMed

    Chen, Ming-biao; Ma, Min; Yang, Qing-xiang; Wang, Shan; Liu, Wen-chang; Zhao, Ying-mei

    2013-09-01

    To provide gist of DC AA 5052 and CC AA 5052 aluminum alloy to industry production and application, the texture variation of cold rolled sheets through thickness direction was studied by X-ray diffraction method, and the difference in texture at surface, quarter and center layer was analyzed. The hot plates of direct chill cast (DC) AA 5052 and continuous cast (CC) AA 5052 aluminum alloy were annealed at 454 degrees C for 4 hours and then cold rolled to different reductions. The strength and volume fraction of the fiber in CC AA 5052 aluminum alloy is larger than in DC AA 5052 aluminum alloy after same rolling reduction The volume fraction of the recrystallization texture cube in the CC AA 5052 aluminum alloy is less than in the DC AA 5052 aluminum alloy, which result in that CC AA 5052 aluminum alloy needs less cold rolling reduction than DC AA 5052 aluminum alloy for generating the texture with same intensity and volume fraction at surface layer, quarter layer and center layer. The manufacturability and performance of CC AA 5052 aluminum alloy is superior to DC AA 5052 aluminum alloy for use in stamping.

  5. Infection with Marek’s disease virus induces high levels of CD8a/a cells in chickens resistant to Marek’s disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The CD8a/a cells have non-traditional roles. CD8a/a cells (T'' cells) usually recognize monomorphic antigen like bacterial lipids presented by non-traditional class I glycoproteins such as BF1 (minor) or Rfp-Y. CD8a/a cells have also been implicated in natural killing with approximately 80% of NK ...

  6. Effects of Initial Temper Condition and Postweld Heat Treatment on the Properties of Dissimilar Friction-Stir-Welded Joints between AA7075 and AA6061 Aluminum Alloys

    NASA Astrophysics Data System (ADS)

    İpekoğlu, Güven; Çam, Gürel

    2014-06-01

    In this study, dissimilar AA7075-O/6061-O and AA7075-T6/6061-T6 butt joints were produced by friction stir welding (FSW), and postweld heat treatment (PWHT) was applied to the joints obtained. The effects of initial temper condition and PWHT on the microstructure and mechanical properties of the dissimilar joints were thus investigated. It was demonstrated that sound dissimilar joints can be produced for both temper conditions. A hardness increase in the joint area ( i.e., strength overmatching) was obtained in the joints produced in the O-temper condition, whereas a hardness loss was observed in the joint area of the joints obtained in the T6 temper condition. It was also well demonstrated that PWHT could be used in order to improve the joint properties for both O and T6 joints provided that the joint is defect-free prior to subsequent heat treatment.

  7. Investigation of Microstructure and Microhardness in Self-Reacting Friction Stir Welded AA2014-T6 and AA2219-T87

    NASA Technical Reports Server (NTRS)

    Horton, K. Renee; McGill, Preston; Barkey, Mark

    2011-01-01

    Friction stir welding (FSW) is a solid state welding process with potential advantages for aerospace and automotive industries dealing with light alloys. Self-reacting friction stir welding (SR-FSW) is one variation of the FSW process being developed at the National Aeronautics and Space Administration (NASA) for use in the fabrication of propellant tanks. This work reports on the microstructure and microhardness of SR-FSW between two dissimilar aluminum alloys. Specifically, the study examines the cross section of the weld joint formed between an AA2014-T6 plate on the advancing side and an AA2219-T87 plate on the retreating side. The microstructural analysis shows an irregularly displaced weld seam from the advancing side past the thermo-mechanical affected zone (TMAZ) into the weld nugget region. There are sharp variations in the microhardness across the weld. These variations are described in the paper and mechanisms for their formation are discussed.

  8. Bacillus thuringiensis Cry3Aa toxin increases the susceptibility of Crioceris quatuordecimpunctata to Beauveria bassiana infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spotted asparagus beetle, Crioceris quatuordecimpunctata (Coleoptera: Chrysomelidae), is one of the most devastating pests of asparagus in China and elsewhere. In this study, we investigated the interaction of Bacillus thuringiensis (Bt) Cry3Aa toxin and the entomopathogenic fungus Beauveria bas...

  9. Chromosomal-gene-mediated inhibition of intestinal and foodborne pathogens by Lactobacillus acidophilus AA11.

    PubMed

    Abo-Amer, Aly E

    2006-01-01

    Approximately 63 strains of Lactobacillus acidophilus were isolated from Egyptian home-made cheese and examined for production of antagonism. Only eight strains demonstrated inhibitory activity against spoilage microorganisms (i.e. Staphylococcus aureus and Bacillus cereus) and pathogens (i.e. E. coli, Salmonella sp. and Shigella sp.). Lactobacillus acidophilus AA11 produced a more antimicrobial activity with a wide range of inhibition. The agent AA11 was sensitive to proteolytic enzymes and retained full activity after 30 min at 100 degrees C. Activity against sensitive cells was bactericidal but not bacteriolytic. The compound was produced during growth phase and can be extracted from the culture supernatant fluids with n-Butanol. 12 % SDS-PAGE analysis of 40% ammonium sulphate precipitated agent showed two peptides with molecular weights of approximately 36 kDa and approximately 29 kDa. No plasmid was identified in Lactobacillus acidophilus AA11 indicating that the genes encoding the inhibitory agent located on the chromosome. These characteristics identify the inhibitory substance as a bacteriocin, designated acidocin AA11 and confer the agent an application potential as a biopreservative.

  10. Draft Genome Sequence of the Putrescine-Producing Strain Lactococcus lactis subsp. lactis 1AA59

    PubMed Central

    del Rio, Beatriz; Linares, Daniel M.; Fernandez, María; Mayo, Baltasar; Martín, M. Cruz

    2015-01-01

    We report here the 2,576,542-bp genome annotated draft assembly sequence of Lactococcus lactis subsp. lactis 1AA59. This strain—isolated from a traditional cheese—produces putrescine, one of the most frequently biogenic amines found in dairy products. PMID:26089428

  11. Prediction of the Hot Flow Stress Behavior of AA6063 Including Mg2Si Dissolution

    NASA Astrophysics Data System (ADS)

    Odoh, Daniel; Mahmoodkhani, Yahya; Whitney, Mark; Wells, Mary

    2017-02-01

    A constitutive model that includes the effect of Mg2Si dissolution during pre-deformation heating and holding has been developed for the prediction of the hot flow stress behavior of AA6063 aluminum alloy. The deformation behavior of homogenized AA6063 aluminum alloy was studied by performing compression tests on a Gleeble 3500 thermomechanical simulator at temperatures ranging from 400 to 550 °C and strain rates from 0.01 to 10 s-1. A one-dimensional model of particle dissolution in spherical coordinate system was developed to determine the Mg-Si solute content during pre-deformation heating and holding. Using the Mg solute content determined from the particle dissolution model, the flow stress during the deformation of AA6063 aluminum alloy at specific temperatures and strain rates was predicted using a modified hyperbolic sine equation. The constitutive model developed was found to be in good agreement with experimental measurements in this study as well as other experimental and model results published in the literature. A 14% increase in flow stress of the alloy was observed for an increase in hold time from 60 to 1500 s at 450 °C. This is due to increased deformation resistance of the alloy as the Mg-Si solute content increases. The modified hyperbolic sine equation developed in this study clearly shows that accounting for Mg-Si solute content improves the ability to accurately predict the flow stress behavior of AA6063 aluminum alloy.

  12. High Bias of DCAP and Aa Analyses of Hg(I)

    SciTech Connect

    Holcomb, H.P.

    2001-05-17

    This brief, but definitive, study indicates that the relatively new spectrometric techniques, DCAP and AA (Atomic Absorption), give high values for mercury when employed to analyze solutions that contain Hg(I) per se or that contain soluble mercury which is or has been subject to reducing conditions.

  13. Optimization of the OPLS-AA Force Field for Long Hydrocarbons.

    PubMed

    Siu, Shirley W I; Pluhackova, Kristyna; Böckmann, Rainer A

    2012-04-10

    The all-atom optimized potentials for liquid simulations (OPLS-AA) force field is a popular force field for simulating biomolecules. However, the current OPLS parameters for hydrocarbons developed using short alkanes cannot reproduce the liquid properties of long alkanes in molecular dynamics simulations. Therefore, the extension of OPLS-AA to (phospho)lipid molecules required for the study of biological membranes was hampered in the past. Here, we optimized the OPLS-AA force field for both short and long hydrocarbons. Following the framework of the OPLS-AA parametrization, we refined the torsional parameters for hydrocarbons by fitting to the gas-phase ab initio energy profiles calculated at the accurate MP2/aug-cc-pVTZ theory level. Additionally, the depth of the Lennard-Jones potential for methylene hydrogen atoms was adjusted to reproduce the densities and the heats of vaporization of alkanes and alkenes of different lengths. Optimization of partial charges finally allowed to reproduce the gel-to-liquid-phase transition temperature for pentadecane and solvation free energies. It is shown that the optimized parameter set (L-OPLS) yields improved hydrocarbon diffusion coefficients, viscosities, and gauche-trans ratios. Moreover, its applicability for lipid bilayer simulations is shown for a GMO bilayer in its liquid-crystalline phase.

  14. 45 CFR 170.575 - Removal of the ONC-AA.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION SPECIFICATIONS, AND CERTIFICATION CRITERIA AND CERTIFICATION PROGRAMS FOR HEALTH INFORMATION TECHNOLOGY ONC HIT Certification Program § 170.575 Removal of the ONC-AA....

  15. 45 CFR 170.575 - Removal of the ONC-AA.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Public Welfare Department of Health and Human Services HEALTH INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION SPECIFICATIONS, AND CERTIFICATION CRITERIA AND CERTIFICATION PROGRAMS FOR HEALTH INFORMATION TECHNOLOGY ONC HIT Certification Program § 170.575 Removal of the ONC-AA....

  16. Suppression of the high-p(T) charged-hadron R(AA) at the LHC.

    PubMed

    Majumder, A; Shen, C

    2012-11-16

    We present a parameter-free postdiction of the high-p(T) charged-hadron nuclear modification factor (R(AA)) in two centralities, measured by the CMS Collaboration in Pb-Pb collisions at the LHC. The evolution of the bulk medium is modeled using viscous fluid dynamics, with parameters adjusted to describe the soft hadron yields and elliptic flow. Assuming the dominance of radiative energy loss, we compute the medium modification of the R(AA) using a perturbative QCD-based formalism, the higher twist scheme. The transverse momentum diffusion coefficient q[over ^] is assumed to scale with the entropy density and is normalized by fitting the R(AA) in the most central Au-Au collisions at the Relativistic Heavy-Ion Collider. This setup is validated in noncentral Au-Au collisions at the Relativistic Heavy-Ion Collider and then extrapolated to Pb-Pb collisions at the LHC, keeping the relation between q[over ^] and entropy density unchanged. We obtain a satisfactory description of the CMS R(AA) over the p(T) range from 10 to 100 GeV.

  17. Larvicidal activity of Bacillus thuringiensis var. israelensis Cry11Aa toxin against Haemonchus contortus.

    PubMed

    DE Lara, Ana Paula DE Souza Stori; Lorenzon, Lucas Bigolin; Vianna, Ana Muñoz; Santos, Francisco Denis Souza; Pinto, Luciano Silva; Aires Berne, Maria Elisabeth; Leite, Fábio Pereira Leivas

    2016-10-01

    Effective control of gastrointestinal parasites is necessary in sheep production. The development of anthelmintics resistance is causing the available chemically based anthelmintics to become less effective. Biological control strategies present an alternative to this problem. In the current study, we tested the larvicidal effects of Bacillus thuringiensis var. israelensis Cry11Aa toxin against Haemonchus contortus larvae. Bacterial suspensions [2 × 108 colony-forming units (CFU) g-1 of the feces] of B. thuringiensis var. israelensis and recombinant Escherichia coli expressing Cry11Aa toxin were added to naturally H. contortus egg-contaminated feces. The larvae were quantified, and significant reductions of 62 and 81% (P < 0·001) were, respectively observed, compared with the control group. A 30 mL bacterial suspension (1 × 108 CFU mL-1) of B. thuringiensis var. israelensis and recombinant E. coli expressing Cry11Aa toxin were then orally administered to lambs naturally infected with H. contortus. Twelve hours after administration, feces were collected and submitted to coprocultures. Significant larvae reductions (P < 0·001) of 79 and 90% were observed respectively compared with the control group. The results suggest that the Cry11Aa toxin of B. thuringiensis var. israelensis is a promising new class of biological anthelmintics for treating sheep against H. contortus.

  18. Optimization of arylindenopyrimidines as potent adenosine A(2A)/A(1) antagonists.

    PubMed

    Shook, Brian C; Rassnick, Stefanie; Chakravarty, Devraj; Wallace, Nathaniel; Ault, Mark; Crooke, Jeffrey; Barbay, J Kent; Wang, Aihua; Leonard, Kristi; Powell, Mark T; Alford, Vernon; Hall, Daniel; Rupert, Kenneth C; Heintzelman, Geoffrey R; Hansen, Kristen; Bullington, James L; Scannevin, Robert H; Carroll, Karen; Lampron, Lisa; Westover, Lori; Russell, Ronald; Branum, Shawn; Wells, Kenneth; Damon, Sandra; Youells, Scott; Beauchamp, Derek; Li, Xun; Rhodes, Kenneth; Jackson, Paul F

    2010-05-01

    Two reactive metabolites were identified in vivo for the dual A(2A)/A(1) receptor antagonist 1. Two strategies were implemented to successfully mitigate the metabolic liabilities associated with 1. Optimization of the arylindenopyrimidines led to a number of amide, ether, and amino analogs having comparable in vitro and in vivo activity.

  19. 49 CFR 178.56 - Specification 4AA480 welded steel cylinders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Type, size, and service pressure. A DOT 4AA480 cylinder is a welded steel cylinder having a water capacity (nominal) not over 1,000 pounds water capacity and a service pressure of 480 psig. Closures welded... the required thickness of the side wall. Seams must be made as follows: (1) Circumferential seams...

  20. Considerations for Consortia as States Transition Away from AA-MAS. NCEO Brief. Number 7

    ERIC Educational Resources Information Center

    National Center on Educational Outcomes, 2014

    2014-01-01

    States with an alternate assessment based on modified achievement standards (AA-MAS) that received a flexibility waiver from some of the requirements of No Child Left Behind are required to phase out their use of this assessment. And, on August 23, 2013, the U.S. Department of Education published a proposed rollback of regulation that allowed the…

  1. Successfully Transitioning from the AA-MAS to the General Assessment. NCEO Policy Directions. Number 22

    ERIC Educational Resources Information Center

    Lazarus, Sheryl; Thurlow, Martha; Christensen, Laurene; Shyyan, Vitaliy

    2014-01-01

    Federal policy initiatives such as the flexibility waivers for accountability are requiring that states transition away from the use of an alternate assessment based on modified achievement standards (AA-MAS). It is expected that those students who had participated in that assessment will instead participate in the state's general assessment (or a…

  2. The AAS to BAS Pathway: Heating Up the Educational Aspiration of CTE Students

    ERIC Educational Resources Information Center

    Kujawa, Tricia A.

    2013-01-01

    The enrollment and transfer behaviors of college students are diverse. As a result, college students travel various pathways to the baccalaureate degree. The purpose of this qualitative study was to better understand the lived experience of students who entered higher education through an associate of applied science (AAS) program and then…

  3. Manufacturing Systems Demonstration: Bimetallic Friction STIR Joining of AA6061 and High Hardness Steel

    DTIC Science & Technology

    2013-05-31

    DESCRIPTION OF FRICTION STIR PROCESSES ................................................... 2 D. DEVELOPMENT OF BIMETALLIC ( ALUMINUM - STEEL ) FRICTION STIR...to successfully join AA6061 aluminum alloy and High Hardness Armor (HHA) steel using the friction stir process (FSP). Metallographic analysis...32262: Detail Specification, Armor Plate Aluminum Alloy, Unweldable Applique 6061 2 MIL-DTL-46100E: Armor Plate, Steel , Wrought, High-Hardness

  4. The effect of welding parameters on surface quality of AA6351 aluminium alloy

    NASA Astrophysics Data System (ADS)

    Yacob, S.; MAli, M. A.; Ahsan, Q.; Ariffin, N.; Ali, R.; Arshad, A.; Wahab, M. I. A.; Ismail, S. A.; Roji, NS M.; Din, W. B. W.; Zakaria, M. H.; Abdullah, A.; Yusof, M. I.; Kamarulzaman, K. Z.; Mahyuddin, A.; Hamzah, M. N.; Roslan, R.

    2015-12-01

    In the present work, the effects of gas metal arc welding-cold metal transfer (GMAW-CMT) parameters on surface roughness are experimentally assessed. The purpose of this study is to develop a better understanding of the effects of welding speed, material thickness and contact tip to work distance on the surface roughness. Experiments are conducted using single pass gas metal arc welding-cold metal transfer (GMAW-CMT) welding technique to join the material. The material used in this experiment was AA6351 aluminum alloy with the thickness of 5mm and 6mm. A Mahr Marsuft XR 20 machine was used to measure the average roughness (Ra) of AA6351 joints. The main and interaction effect analysis was carried out to identify process parameters that affect the surface roughness. The results show that all the input process parameters affect the surface roughness of AA6351 joints. Additionally, the average roughness (Ra) results also show a decreasing trend with increased of welding speed. It is proven that gas metal arc welding-cold metal transfer (GMAW-CMT)welding process has been successful in term of providing weld joint of good surface quality for AA6351 based on the low value surface roughness condition obtained in this setup. The outcome of this experimental shall be valuable for future fabrication process in order to obtained high good quality weld.

  5. Influence of FSW pin tool geometry on plastic flow of AA7075 T651

    NASA Astrophysics Data System (ADS)

    Lertora, Enrico; Mandolfino, Chiara; Gambaro, Carla

    2016-10-01

    In this paper the behaviour of the plastic flow during Friction Stir Welding of AA7075 T651 plates, realized with different shaped tools, has been investigated. In particular, the influence of the shape of three tools was studied using copper strips placed along the welds. After welding, radiography and metallurgical analysis were used in order to investigate the marker movement and its fragmentation.

  6. RETRACTED ARTICLE: Microstructural evolution of AA7449 aerospace alloy refined by intensive shearing

    NASA Astrophysics Data System (ADS)

    Haghayeghi, R.; Nastac, L.

    2012-10-01

    Many aerospace alloys are sensitive to their composition thus cannot be chemically grain refined. In addition, only 1% grain refiners can act as nuclei for refining the structure. In this paper, physical refinement by intensive shearing above liquidus as an alternative technique will be investigated for AA7449 aerospace alloy. The results can open a new gateway for aerospace industry for refining their microstructure.

  7. Spectroscopic Classification of SN 2017aas as a Type Ia Supernova

    NASA Astrophysics Data System (ADS)

    Zhang, Jujia; Lu, Kaixin; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Yang, Zesheng

    2017-02-01

    We obtained an optical spectrum (range 340-830 nm) of SN 2017aas (=PTSS-17dib),discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.04.86 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  8. Susceptibility of Spodoptera frugiperda and S. exigua to Bacillus thuringiensis Vip3Aa insecticidal protein.

    PubMed

    Chakroun, Maissa; Bel, Yolanda; Caccia, Silvia; Abdelkefi-Mesrati, Lobna; Escriche, Baltasar; Ferré, Juan

    2012-07-01

    The Vip3Aa protein is an insecticidal protein secreted by Bacillus thuringiensis during the vegetative stage of growth. The activity of this protein has been tested after different steps/protocols of purification using Spodoptera frugiperda as a control insect. The results showed that the Vip3Aa protoxin was stable and retained full toxicity after being subjected to common biochemical steps used in protein purification. Bioassays with the protoxin in S. frugiperda and S. exigua showed pronounced differences in LC(50) values when mortality was measured at 7 vs. 10d. At 7d most live larvae were arrested in their development. LC(50) values of "functional mortality" (dead larvae plus larvae remaining in the first instar), measured at 7d, were similar or even lower than the LC(50) values of mortality at 10d. This strong growth inhibition was not observed when testing the trypsin-activated protein (62 kDa) in either species. S. exigua was less susceptible than S. frugiperda to the protoxin form, with LC(50) values around 10-fold higher. However, both species were equally susceptible to the trypsin-activated form. Processing of Vip3Aa protoxin to the activated form was faster with S. frugiperda midgut juice than with S. exigua midgut juice. The results strongly suggest that the differences in the rate of activation of the Vip3Aa protoxin between both species are the basis for the differences in susceptibility towards the protoxin form.

  9. Echocardiographic diagnosis of systemic AA amyloidosis presenting with acute liver failure.

    PubMed

    Morelli, Sergio; Bonfiglio, Daniele; Galasso, Laura

    2010-08-01

    We report the case of a 73-year-old man admitted to our hospital for acute hepatic failure. Antemortem diagnosis of systemic AA amyloidosis was made because of typical electrocardiographic and echocardiographic findings, in the absence of the classic clinical picture of kidney involvement.

  10. 7 CFR 51.1176 - U.S. Grade AA Juice (Double A).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS) United States Standards for Grades of Florida Oranges and Tangelos Standards for Internal Quality of Common Sweet Oranges (citrus Sinensis (l) Osbeck) § 51.1176 U.S. Grade AA Juice (Double A). Any lot of oranges, the juice content of which meets the following requirements, may be designated...

  11. 7 CFR 51.1176 - U.S. Grade AA Juice (Double A).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS) United States Standards for Grades of Florida Oranges and Tangelos Standards for Internal Quality of Common Sweet Oranges (citrus Sinensis (l) Osbeck) § 51.1176 U.S. Grade AA Juice (Double A). Any lot of oranges, the juice content of which meets the following requirements, may be designated...

  12. 7 CFR 51.1176 - U.S. Grade AA Juice (Double A).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS) United States Standards for Grades of Florida Oranges and Tangelos Standards for Internal Quality of Common Sweet Oranges (citrus Sinensis (l) Osbeck) § 51.1176 U.S. Grade AA Juice (Double A). Any lot of oranges, the juice content of which meets the following requirements, may be designated...

  13. Prediction of the Hot Flow Stress Behavior of AA6063 Including Mg2Si Dissolution

    NASA Astrophysics Data System (ADS)

    Odoh, Daniel; Mahmoodkhani, Yahya; Whitney, Mark; Wells, Mary

    2017-03-01

    A constitutive model that includes the effect of Mg2Si dissolution during pre-deformation heating and holding has been developed for the prediction of the hot flow stress behavior of AA6063 aluminum alloy. The deformation behavior of homogenized AA6063 aluminum alloy was studied by performing compression tests on a Gleeble 3500 thermomechanical simulator at temperatures ranging from 400 to 550 °C and strain rates from 0.01 to 10 s-1. A one-dimensional model of particle dissolution in spherical coordinate system was developed to determine the Mg-Si solute content during pre-deformation heating and holding. Using the Mg solute content determined from the particle dissolution model, the flow stress during the deformation of AA6063 aluminum alloy at specific temperatures and strain rates was predicted using a modified hyperbolic sine equation. The constitutive model developed was found to be in good agreement with experimental measurements in this study as well as other experimental and model results published in the literature. A 14% increase in flow stress of the alloy was observed for an increase in hold time from 60 to 1500 s at 450 °C. This is due to increased deformation resistance of the alloy as the Mg-Si solute content increases. The modified hyperbolic sine equation developed in this study clearly shows that accounting for Mg-Si solute content improves the ability to accurately predict the flow stress behavior of AA6063 aluminum alloy.

  14. 7 CFR 51.1176 - U.S. Grade AA Juice (Double A).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Florida Oranges and Tangelos Standards for Internal Quality of Common Sweet Oranges (citrus Sinensis (l) Osbeck) § 51.1176 U.S. Grade AA Juice (Double A). Any lot of oranges, the juice content of which meets the following requirements,...

  15. SN 2012aa: A transient between Type Ibc core-collapse and superluminous supernovae

    NASA Astrophysics Data System (ADS)

    Roy, R.; Sollerman, J.; Silverman, J. M.; Pastorello, A.; Fransson, C.; Drake, A.; Taddia, F.; Fremling, C.; Kankare, E.; Kumar, B.; Cappellaro, E.; Bose, S.; Benetti, S.; Filippenko, A. V.; Valenti, S.; Nyholm, A.; Ergon, M.; Sutaria, F.; Kumar, B.; Pandey, S. B.; Nicholl, M.; Garcia-Álvarez, D.; Tomasella, L.; Karamehmetoglu, E.; Migotto, K.

    2016-12-01

    Context. Research on supernovae (SNe) over the past decade has confirmed that there is a distinct class of events which are much more luminous (by 2 mag) than canonical core-collapse SNe (CCSNe). These events with visual peak magnitudes ≲-21 are called superluminous SNe (SLSNe). The mechanism that powers the light curves of SLSNe is still not well understood. The proposed scenarios are circumstellar interaction, the emergence of a magnetar after core collapse, or disruption of a massive star through pair production. Aims: There are a few intermediate events which have luminosities between these two classes. They are important for constraining the nature of the progenitors of these two different populations and their environments and powering mechanisms. Here we study one such object, SN 2012aa. Methods: We observed and analysed the evolution of the luminous Type Ic SN 2012aa. The event was discovered by the Lick Observatory Supernova Search in an anonymous galaxy (z ≈ 0.08). The optical photometric and spectroscopic follow-up observations were conducted over a time span of about 120 days. Results: With an absolute V-band peak of - 20 mag, the SN is an intermediate-luminosity transient between regular SNe Ibc and SLSNe. SN 2012aa also exhibits an unusual secondary bump after the maximum in its light curve. For SN 2012aa, we interpret this as a manifestation of SN-shock interaction with the circumstellar medium (CSM). If we assume a 56Ni-powered ejecta, the quasi-bolometric light curve requires roughly 1.3 M⊙ of 56Ni and an ejected mass of 14M⊙. This also implies a high kinetic energy of the explosion, 5.4 × 1051 erg. On the other hand, the unusually broad light curve along with the secondary peak indicate the possibility of interaction with CSM. The third alternative is the presence of a central engine releasing spin energy that eventually powers the light curve over a long time. The host of SN 2012aa is a star-forming Sa/Sb/Sbc galaxy. Conclusions

  16. Transplantation of PDGF-AA-Overexpressing Oligodendrocyte Precursor Cells Promotes Recovery in Rat Following Spinal Cord Injury.

    PubMed

    Yao, Zong-Feng; Wang, Ying; Lin, Yu-Hong; Wu, Yan; Zhu, An-You; Wang, Rui; Shen, Lin; Xi, Jin; Qi, Qi; Jiang, Zhi-Quan; Lü, He-Zuo; Hu, Jian-Guo

    2017-01-01

    Our previous study showed that Schwann cells (SCs) promote survival, proliferation and migration of co-transplanted oligodendrocyte progenitor cells (OPCs) and neurological recovery in rats with spinal cord injury (SCI). A subsequent in vitro study confirmed that SCs modulated OPC proliferation and migration by secreting platelet-derived growth factor (PDGF)-AA and fibroblast growth factor-2 (FGF)-2. We also found that PDGF-AA stimulated OPC proliferation and their differentiation into oligodendrocytes (OLs) at later stages. We therefore speculated that PDGF-AA administration can exert the same effect as SC co-transplantation in SCI repair. To test this hypothesis, in this study we investigated the effect of transplanting PDGF-AA-overexpressing OPCs in a rat model of SCI. We found that PDGF-AA overexpression in OPCs promoted their survival, proliferation, and migration and differentiation into OLs in vivo. OPCs overexpressing PDGF-AA were also associated with increased myelination and tissue repair after SCI, leading to the recovery of neurological function. These results indicate that PDGF-AA-overexpressing OPCs may be an effective treatment for SCI.

  17. Transplantation of PDGF-AA-Overexpressing Oligodendrocyte Precursor Cells Promotes Recovery in Rat Following Spinal Cord Injury

    PubMed Central

    Yao, Zong-Feng; Wang, Ying; Lin, Yu-Hong; Wu, Yan; Zhu, An-You; Wang, Rui; Shen, Lin; Xi, Jin; Qi, Qi; Jiang, Zhi-Quan; Lü, He-Zuo; Hu, Jian-Guo

    2017-01-01

    Our previous study showed that Schwann cells (SCs) promote survival, proliferation and migration of co-transplanted oligodendrocyte progenitor cells (OPCs) and neurological recovery in rats with spinal cord injury (SCI). A subsequent in vitro study confirmed that SCs modulated OPC proliferation and migration by secreting platelet-derived growth factor (PDGF)-AA and fibroblast growth factor-2 (FGF)-2. We also found that PDGF-AA stimulated OPC proliferation and their differentiation into oligodendrocytes (OLs) at later stages. We therefore speculated that PDGF-AA administration can exert the same effect as SC co-transplantation in SCI repair. To test this hypothesis, in this study we investigated the effect of transplanting PDGF-AA-overexpressing OPCs in a rat model of SCI. We found that PDGF-AA overexpression in OPCs promoted their survival, proliferation, and migration and differentiation into OLs in vivo. OPCs overexpressing PDGF-AA were also associated with increased myelination and tissue repair after SCI, leading to the recovery of neurological function. These results indicate that PDGF-AA-overexpressing OPCs may be an effective treatment for SCI. PMID:28377695

  18. Experimental study of albumin and lysozyme adsorption onto acrylic acid (AA) and 2-hydroxyethyl methacrylate (HEMA) surfaces.

    PubMed

    Moradi, Omid; Modarress, Hamid; Noroozi, Mehdi

    2004-03-01

    Many commercial soft contact lenses are based on poly-2-hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) hydrogels. The adsorption of proteins, albumin and lysozyme, on such contact lens surfaces may cause problems in their applications. In this work the adsorption of proteins, albumin and lysozyme, on hydrogel surfaces, AA and HEMA, was investigated as a function of concentration of protein. Also the effects of pH and ionic strength of protein solution on the adsorption of protein were examined. The obtained results indicated that the degree of adsorption of protein increased with the concentration of protein, and the adsorption of albumin on HEMA surface at the studied pHs (6.2-8.6) was higher than AA surface, whereas the adsorption of lysozyme on AA surface at the same pHs was higher than HEMA. The change in ionic strength of protein solution affected the proteins adsorption on both AA and HEMA surfaces. Also, the amount of sodium ions deposited on the AA surface was much higher than HEMA surface. This effect can be related to the negative surface charge of AA and its higher tendency for adsorption of sodium ions compared to the HEMA surface.

  19. Cloning of an arylalkylamine N-acetyltransferase (aaNAT1) from Drosophila melanogaster expressed in the nervous system and the gut.

    PubMed Central

    Hintermann, E; Grieder, N C; Amherd, R; Brodbeck, D; Meyer, U A

    1996-01-01

    In insects, neurotransmitter catabolism, melatonin precursor formation, and sclerotization involve arylalkylamine N-acetyltransferase (aaNAT, EC 2.3.1.87) activity. It is not known if one or multiple aaNAT enzymes are responsible for these activities. We recently have purified an aaNAT from Drosophila melanogaster. Here, we report the cloning of the corresponding aaNAT cDNA (aaNAT1) that upon COS cell expression acetylates dopamine, tryptamine, and the immediate melatonin precursor serotonin. aaNAT1 represents a novel gene family unrelated to known acetyl-transferases, except in two weakly conserved amino acid motifs. In situ hybridization studies of aaNAT1 mRNA in embryos reveal hybridization signals in the brain, the ventral cord, the gut, and probably in oenocytes, indicating a broad tissue distribution of aaNAT1 transcripts. Moreover, in day/ night studies we demonstrate a diurnal rhythm of melatonin concentration without a clear-cut change in aaNAT1 mRNA levels. The data suggest that tissue-specific regulation of aaNAT1 may be associated with different enzymatic functions and do not exclude the possibility of additional aaNAT genes. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8901578

  20. Mapping CSF biomarker profiles onto NIA-AA guidelines for Alzheimer's disease.

    PubMed

    Alexopoulos, Panagiotis; Roesler, Jennifer; Thierjung, Nathalie; Werle, Lukas; Buck, Dorothea; Yakushev, Igor; Gleixner, Lena; Kagerbauer, Simone; Ortner, Marion; Grimmer, Timo; Kübler, Hubert; Martin, Jan; Laskaris, Nikolaos; Kurz, Alexander; Perneczky, Robert

    2016-10-01

    The National Institute on Aging-Alzheimer's Association (NIA-AA) guidelines for Alzheimer's disease (AD) propose the categorization of individuals according to their biomarker constellation. Though the NIA-AA criteria for preclinical AD and AD dementia have already been applied in conjunction with imaging AD biomarkers, the application of the criteria using comprehensive cerebrospinal fluid (CSF) biomarker information has not been thoroughly studied yet. The study included a monocentric cohort with healthy (N = 41) and disease (N = 22) controls and patients with AD dementia (N = 119), and a multicentric sample with healthy controls (N = 116) and patients with AD dementia (N = 102). The CSF biomarkers β-amyloid 1-42, total tau, and phosphorylated tau at threonine 181 were measured with commercially available assays. Biomarker values were trichotomized into positive for AD, negative, or borderline. In controls the presence of normal CSF profiles varied between 13.6 and 25.4 % across the studied groups, while up to 8.6 % of them had abnormal CSF biomarkers. In 40.3-52.9 % of patients with AD dementia, a typical CSF profile for AD was detected. Approximately 40 % of the potential biomarker constellations are not considered in the NIA-AA guidelines, and more than 40 % of participants could not be classified into the NIA-AA categories with distinct biomarker constellations. Here, a refined scheme covering all potential biomarker constellations is proposed. These results enrich the discussion on the NIA-AA guidelines and point to a discordance between clinical symptomatology and CSF biomarkers even in patients with full-blown AD dementia, who are supposed to have a clearly positive for AD neurochemical profile.

  1. The AAS ``Semi-centennial" Meeting: Northwestern University and Yerkes Observatory, September 1947

    NASA Astrophysics Data System (ADS)

    Osterbrock, D. E.

    1999-05-01

    The AAS celebrated its "semi-centennial" fifty-two years ago! It was actually the fiftieth anniversary of the "First Conference" of astronomers and astrophysicists held at the dedication of Yerkes Observatory in 1897, which led to the actual formation of the Society two years later. Otto Struve, president of the AAS, was publicizing the fiftieth anniversary of his Yerkes Observatory in 1947, and he simply announced it was also the semi-centennial of the Society. Joel Stebbins, the grand old man of the AAS who had joined it as a graduate student in 1900, and held nearly every office in the Society from councilor to president, supported Struve's early celebration of the anniversary, probably largely because he was to retire himself in 1948. The meeting was held at Northwestern University and at Yerkes. There were then 625 AAS members. About 140 of them attended the meeting, and presented some 50 papers, all oral, with no parallel sessions. Struve organized a symposium on stellar atmospheres, with 5 invited speakers, and the great majority of the contributed papers were also on stars, a few on nebulae and interstellar matter, one on galaxies, and none on cosmology. Not to be outdone, Gerard P. Kuiper, who had recently succeeded Struve as director of Yerkes Observatory, organized a second symposium on the atmospheres of the planets, held at Yerkes immediately after the AAS meeting. After two days of sessions at Evanston, the members had driven to Williams Bay for the closing session Saturday, at which Struve and Stebbins gave their versions of the history of the observatory and of the Society. The two symposia formed the bases for two important books, Astrophysics: A Topical Symposium, and The Atmospheres of the Earth and the Planets, edited by J. Allen Hynek and Kuiper respectively.

  2. Enhancement of the Stress Corrosion Sensitivity of AA5083 by Heat Treatment

    NASA Astrophysics Data System (ADS)

    Gao, Jie; Quesnel, David J.

    2011-02-01

    In this study, the stress corrosion cracking (SCC) resistance of AA5083 is intentionally degraded by a series of progressively longer annealing treatments at 448 K (175 °C) that create a two-phase microstructure. Precipitation of strongly anodic Mg2Al3, known as β-phase, occurs heterogeneously with substantial precipitation along the grain boundaries, as observed by differential interference microscopy. Ultimate tensile strength, yield strength, and strain to failure of AA5083 alloy were found to be independent of the amount of β-phase precipitates, making AA5083 an ideal system to study the relative contributions of anodic dissolution and hydrogen embrittlement. Open circuit dropwise exposure SCC tests with precracked double cantilever beam (DCB) specimens made from the AA5083 alloy with different heat treatment conditions were conducted using 3.5 pct NaCl solution at an initial stress intensity factor ( K I ) of 1 5 {{ksi}}sqrt {{in}} .( { 1 6. 5 {{MPa}}sqrt {{m}} } ). Two SCC characteristics, initial crack growth rate and incubation time, were found to be strongly dependent on the amount of β-phase precipitates. Initial crack growth rate increased sigmoidally as a function of heat treatment time with an inflection point between 120 and 240 hours of sensitization time, while the incubation time decreases monotonically with sensitization time. Additionally, fracture surfaces investigated by scanning electron microscopy demonstrated characteristics of intergranular cracking with multiple crack tips. Discussion centers on the evidence supporting anodic dissolution of β-phase grain boundary precipitates as a primary mechanism of SCC in severely sensitized AA5083 alloy and the potential contribution of hydrogen embrittlement in the failure of grain boundary ligaments between β-phase grain boundary precipitates in less severely sensitized conditions.

  3. Performance of AA5052 alloy anode in alkaline ethylene glycol electrolyte with dicarboxylic acids additives for aluminium-air batteries

    NASA Astrophysics Data System (ADS)

    Wang, DaPeng; Zhang, DaQuan; Lee, KangYong; Gao, LiXin

    2015-11-01

    Dicarboxylic acid compounds, i.e. succinic acid (SUA), adipic acid (ADA) and sebacic acid (SEA), are used as electrolyte additives in the alkaline ethylene glycol solution for AA5052 aluminium-air batteries. It shows that the addition of dicarboxylic acids lowers the hydrogen gas evolution rate of commercial AA5052 aluminium alloy anode. AA5052 aluminium alloy has wide potential window for electrochemical activity and better discharge performance in alkaline ethylene glycol solution containing dicarboxylic acid additives. ADA has the best inhibition effect for the self-corrosion of AA5052 anode among the three dicarboxylic acid additives. Fourier transform infrared spectroscopy (FT-IR) reveals that dicarboxylic acids and aluminium ions can form coordination complexes. Quantum chemical calculations shows that ADA has a smaller energy gap (ΔE, the energy difference between the lowest unoccupied orbital and the highest occupied orbital), indicating that ADA has the strongest interaction with aluminium ions.

  4. Interfacial and Mechanical Behavior of AA5456 Filling Friction-Stir-Welded Lap Joints Using Similar and Dissimilar Pins

    NASA Astrophysics Data System (ADS)

    Behmand, Saleh Alaei; Mirsalehi, Seyyed Ehsan; Omidvar, Hamid; Safarkhanian, Mohammad Ali

    2016-10-01

    In this article, filling friction stir welding (FFSW) of the remaining exit holes of AA5456 alloy friction-stir-welded lap joints was studied. For this purpose, the influences of different rotating speeds, holding times, and pin materials, AA5456 and AA2024, on the metallurgical structure and joint strength were investigated. The observations showed that defect-free lap joints are successfully obtainable by this method using similar and dissimilar consumable pins. The results indicated that the higher rotating speed and holding time adversely affect the weld performance. The best result was achieved for 30 seconds holding time, 500 rpm rotating speed, and AA2024 consumable pin. In this condition, a lap shear strength of 10 pct higher than that of the nonfilled joint, equivalent to about 94 pct of the original defect-free FSW joint, was obtained, whereas the GTAW filled joint showed only approximately 87 pct of the continuous FSW joint strength.

  5. Lu AA21004, a multimodal psychotropic agent, in the prevention of relapse in adult patients with generalized anxiety disorder.

    PubMed

    Baldwin, David S; Loft, Henrik; Florea, Ioana

    2012-07-01

    The purpose of this study was to investigate the long-term maintenance of the efficacy of Lu AA21004 5 or 10 mg/day in the prevention of relapse in patients with generalized anxiety disorder (GAD). Patients (n = 687) with a primary diagnosis of GAD (DSM-IV criteria) and a baseline Hamilton Anxiety (HAM-A) total score of at least 20 underwent a 20-week, open-label Lu AA21004 treatment. In all, 459 patients responded and were randomized to 24-56 weeks of a double-blind treatment with Lu AA21004 (n = 229) or placebo (n = 230). The predefined primary efficacy endpoint was time to relapse (HAM-A total score ≥ 15) using a Cox model; the key secondary efficacy endpoint under multiplicity control was time to relapse for patients responding to treatment for at least 12 weeks. The primary analysis showed a statistically significant effect of Lu AA21004 relative to the placebo on the time to relapse of GAD, with a hazard ratio of 2.71 (P < 0.001). There was a statistically significant effect of Lu AA21004 in the stable responders (hazard ratio = 3.06, P < 0.001). Lu AA21004 was well tolerated, with withdrawal rates due to adverse events of 9% (open-label) and 3% (placebo) and 4% (Lu AA21004) in the double-blind period. In this study, Lu AA21004 5 or 10 mg/day was efficacious in preventing relapse and was well tolerated in the maintenance treatment of GAD.

  6. Alanine scanning analyses of the three major loops in domain II of Bacillus thuringiensis mosquitocidal toxin Cry4Aa.

    PubMed

    Howlader, Mohammad Tofazzal Hossain; Kagawa, Yasuhiro; Miyakawa, Ai; Yamamoto, Ayaka; Taniguchi, Tetsuya; Hayakawa, Tohru; Sakai, Hiroshi

    2010-02-01

    Cry4Aa produced by Bacillus thuringiensis is a dipteran-specific toxin and is of great interest for developing a bioinsecticide to control mosquitoes. Therefore, it is very important to characterize the functional motif of Cry4Aa that is responsible for its mosquitocidal activity. In this study, to characterize a potential receptor binding site, namely, loops 1, 2, and 3 in domain II, we constructed a series of Cry4Aa mutants in which a residue in these three loops was replaced with alanine. A bioassay using Culex pipiens larvae revealed that replacement of some residues affected the mosquitocidal activity of Cry4Aa, but the effect was limited. This finding was partially inconsistent with previous results which suggested that replacement of the Cry4Aa loop 2 results in a significant loss of mosquitocidal activity. Therefore, we constructed additional mutants in which multiple (five or six) residues in loop 2 were replaced with alanine. Although the replacement of multiple residues also resulted in some decrease in mosquitocidal activity, the mutants still showed relatively high activity. Since the insecticidal spectrum of Cry4Aa is specific, Cry4Aa must have a specific receptor on the surface of the target tissue, and loss of binding to the receptor should result in a complete loss of mosquitocidal activity. Our results suggested that, unlike the receptor binding site of the well-characterized molecule Cry1, the receptor binding site of Cry4Aa is different from loops 1, 2, and 3 or that there are multiple binding sites that work cooperatively for receptor binding.

  7. Bifunctional CYP81AA proteins catalyse identical hydroxylations but alternative regioselective phenol couplings in plant xanthone biosynthesis

    PubMed Central

    El-Awaad, Islam; Bocola, Marco; Beuerle, Till; Liu, Benye; Beerhues, Ludger

    2016-01-01

    Xanthones are natural products present in plants and microorganisms. In plants, their biosynthesis starts with regioselective cyclization of 2,3′,4,6-tetrahydroxybenzophenone to either 1,3,5- or 1,3,7-trihydroxyxanthones, catalysed by cytochrome P450 (CYP) enzymes. Here we isolate and express CYP81AA-coding sequences from Hypericum calycinum and H. perforatum in yeast. Microsomes catalyse two consecutive reactions, that is, 3′-hydroxylation of 2,4,6-trihydroxybenzophenone and C–O phenol coupling of the resulting 2,3′,4,6-tetrahydroxybenzophenone. Relative to the inserted 3′-hydroxyl, the orthologues Hc/HpCYP81AA1 cyclize via the para position to form 1,3,7-trihydroxyxanthone, whereas the paralogue HpCYP81AA2 directs cyclization to the ortho position, yielding the isomeric 1,3,5-trihydroxyxanthone. Homology modelling and reciprocal mutagenesis reveal the impact of S375, L378 and A483 on controlling the regioselectivity of HpCYP81AA2, which is converted into HpCYP81AA1 by sextuple mutation. However, the reciprocal mutations in HpCYP81AA1 barely affect its regiospecificity. Product docking rationalizes the alternative C–O phenol coupling reactions. Our results help understand the machinery of bifunctional CYPs. PMID:27145837

  8. Expression, purification, kinetic, and structural characterization of an alpha-class carbonic anhydrase from Aedes aegypti (AaCA1).

    PubMed

    Fisher, S Zoë; Tariku, Iyerus; Case, Nicolette M; Tu, Chingkuang; Seron, Teri; Silverman, David N; Linser, Paul J; McKenna, Robert

    2006-08-01

    Carbonic anhydrases (CAs) are zinc-containing metalloenzymes that catalyze the interconversion of carbon dioxide and bicarbonate. The alpha-class CAs are found predominantly in vertebrates, but they are also expressed in insects like mosquitoes. Recently, an alpha-CA from the midgut of Aedes aegypti larvae (AaCA1) was identified, cloned, and subsequently shown to share high sequence homologous to human CA I (HCA I). This paper presents the bacterial expression, purification, and kinetic characterization of the soluble CA domain of AaCA1. The data show AaCA1 is a highly active CA that displays inhibition by methazolamide and ethoxzolamide with nM affinity. Additionally, a homology model of AaCA1, based on the crystal structure of HCA I, is presented and the overall structure, active site, and surface charge properties are compared to those of HCA I and II. Measurements of catalysis show that AaCA1 is more like HCA II in terms of proton transfer, but more similar to HCA I in terms of conversion of carbon dioxide to bicarbonate, and these differences are rationalized in terms of structure. These results also indicate that amino acid differences in the active site of AaCA1 compared to human CAs could be used to design specific CA inhibitors for the management of mosquito populations.

  9. Specific binding of activated Vip3Aa10 to Helicoverpa armigera brush border membrane vesicles results in pore formation.

    PubMed

    Liu, Jing-Guo; Yang, Ai-Zhen; Shen, Xiao-Hong; Hua, Bao-Guang; Shi, Guang-Lu

    2011-10-01

    Helicoverpa armigera is one of the most harmful pests in China. Although it had been successfully controlled by Cry1A toxins, some H. armigera populations are building up resistance to Cry1A toxins in the laboratory. Vip3A, secreted by Bacillus thuringiensis, is another potential toxin against H. armigera. Previous reports showed that activated Vip3A performs its function by inserting into the midgut brush border membrane vesicles (BBMV) of susceptible insects. To further investigate the binding of Vip3A to BBMV of H. armigera, the full-length Vip3Aa10 toxin expressed in Escherichia coli was digested by trypsin or midgut juice extract, respectively. Among the fragments of digested Vip3Aa10, only a 62kDa fragment (Vip3Aa10-T) exhibited binding to BBMV of H. armigera and has insecticidal activity. Moreover, this interaction was specific and was not affected by the presence of Cry1Ab toxin. Binding of Vip3Aa10-T to BBMV resulted in the formation of an ion channel. Unlike Cry1A toxins, Vip3Aa10-T was just slightly associated with lipid rafts of BBMV. These data suggest that although activated Vip3Aa10 specifically interacts with BBMV of H. armigera and forms an ion channel, the mode of action of it may be different from that of Cry1A toxins.

  10. The Disk and Jet of the Classical T Tauri Star AA Tau

    NASA Technical Reports Server (NTRS)

    Grady, Carol A.; Woodgate, Bruce E.

    2012-01-01

    Previous studies of the classical T-Tauri star AA Tau have interpreted the UX Ononis-like photopolarimetric variability as being due to a warp in the inner disk caused by an inclined stellar magnetic dipole field. We test that these effects are macroscopically observable in the inclination and alignment of the disk. We use HST/STIS coronagraphic detection of the disk to measure the outer disk radius and inclination and find that the inner disk is both misinclined and misaligned with respect to the outer disk. AA Tau drives a faint jet which is also misaligned with respect to the outer disk minor axis. The jet is also poorly colimated near the sun. The measured inclination 71 +/- 1 deg is above the inclination range suggested for stars with UX Ononis-like variability, indicating that dust grains in the disk have grown and settled toward the disk midplane.

  11. An update on the correlation between the cosmic radiation intensity and the geomagnetic AA index

    NASA Technical Reports Server (NTRS)

    Shea, M. A.; Smart, D. F.

    1985-01-01

    A statistical study between the cosmic ray intensity, as observed by a neutron monitor, and of the geomagnetic aa index, as representative of perturbations in the plasma and interplanetary magnetic field in the heliosphere, has been updated to specifically exclude time periods around the reversal of the solar magnetic field. The results of this study show a strong negative correlation for the period 1960 through 1968 with a correlation coefficient of approximately -0.86. However, there is essentially no correlation between the cosmic ray intensity and the aa index for the period 1972-1979 (i.e. correlation coefficient less than 0.16). These results would appear to support the theory of preferential particle propagation into the heliosphere vis the ecliptic during the period 1960-1968 and via the solar polar regions during 1972-1979.

  12. Surface Tension of Organic Liquids Using the OPLS/AA Force Field.

    PubMed

    Zubillaga, Rafael A; Labastida, Ariana; Cruz, Bibiana; Martínez, Juan Carlos; Sánchez, Enrique; Alejandre, José

    2013-03-12

    Molecular dynamics simulations are performed to obtain the surface tension of 61 organic liquids using the OPLS/AA (all-atom optimized potential for liquid simulations). The force field parameters are the same as those recently used (Caleman et al. J. Chem. Theory Comput.2012, 8, 61) to determine several thermodynamic properties of 146 organic liquids. The correct evaluation of surface tension using slab simulations of liquids requires one to properly take into account the long-range interactions (Trukhymchuk and Alejandre J. Chem. Phys.1999, 111, 8510). In addition, the liquid density from slab simulations has to be the same as that obtained in liquid simulations at constant temperature and pressure. The new results of surface tensions from this work improve those reported by Caleman et al. The OPLS/AA force field gives good surface tensions compared with experimental data for most of the systems studied in this work, although it was developed to simulate liquids.

  13. Immobilization of aminoglycosidic aminocyclitols antibiotic onto soap-free poly(MMA-EA-AA) latex particles.

    PubMed

    Kang, Kai; Kan, Chengyou; Du, Yi; Liu, Deshan; Yeung, Anthony

    2006-01-01

    Monodispersed soap-free poly(MMA-EA-AA) latex particles with surface carboxyl groups were synthesized by emulsion polymerization of methyl methacrylate (MMA), ethyl acrylate (EA) and acrylic acid (AA) in aqueous medium, and streptomycin sulfate (SMS) was immobilized onto these particles using three different methods. A model experiment was designed to test the feasibility of the reaction between the carboxyl groups of polymer and the amino groups of the medicine. The covalent coupling between the latex particles and the medicine was confirmed by XPS. Results showed that the medicine molecules were located on the particle surface after immobilization, and the coupling efficiency of SMS in pre-adsorption method was higher than that in direct method. The highest coupling efficiency of this medicine was achieved using the spacer-arm method. It was demonstrated that the immobilized medicine had similar antimicrobial activity as the free form using Escherichia coli as an evaluating organism.

  14. Work capacity and anticipation in A.A. Ukhtomsky's concept of dominance

    NASA Astrophysics Data System (ADS)

    Pavlova, L. P.

    2015-08-01

    This paper presents the results of theoretical and experimental investigations of human activity and anticipation based on A.A. Ukhtomsky's concept of brain dominance - a non-equilibrium system-forming factor in living systems. Facts on the stages of dominance formation are presented in relation to the creative abilities of the human brain and the role of fatigue as a "lever" for increasing systems' work capacity on the basis of "trace exaltation". Individually, specific features of dominantogenesis are compared with variations in behavioural types. On the basis of chronotopic EEG analysis, we delineate cortical dominants that underlie individual specifics of cognitive processes. The relation is shown between anticipation and the "expansion of dominants" - the broadening of "distal perception" in time and space, as framed by A.A. Ukhtomsky.

  15. PVA/AA photopolymers and PA-LCoS devices combined for holographic data storage

    NASA Astrophysics Data System (ADS)

    Márquez, Andrés.; Martínez, Francisco J.; Fernández, Roberto; Gallego, Sergi; Álvarez, Mariela L.; Pascual, Inmaculada; Beléndez, Augusto

    2016-09-01

    We introduce a polyvinil alcohol/acrylamide (PVA/AA) photopolymer compound in a holographic memory testing platform to provide experimental results for storage and retrieval of information. We also investigate different codification schemes for the data pages addressed onto the parallel-addressed liquid crystal on silicon (PA-LCoS) device, used as the data pager, such as binary intensity modulation (BIM), and hybrid-ternary modulation (HTM), and we will see that an actual approximation for HTM can be obtained with a PA-LCoS device. We will also evaluate the effect of the time fluctuations in the PA-LCoS microdisplays onto the BIM and HTM regimes. Good results in terms of signal-tonoise ratio and bit-error ratio are provided with the experimental system and using the PVA/AA photopolymer produced in our lab, thus showing its potential and interest for future research focused on this material with highly tunable properties.

  16. hcp metal nanoclusters with hexagonal A-A bilayer stacking stabilized by enhanced covalent bonding

    SciTech Connect

    Li, Shunfang; Li, Haisheng; Xue, Xinlian; Jia, Yu; Guo, Zheng Xiao; Zhang, Zhenyu; Gong, Xingao

    2010-01-01

    First-principles total energy calculations within density functional theory have been performed to study the geometric and electronic structures of Ru{sub n} nanoclusters of varying size n (14{<=}n{<=}42). Strikingly, for the size range of n=14 to 38, the clusters always prefer a hexagonal bilayer structure with A-A stacking, rather than some of the more closely packed forms, or bilayer with A-B stacking. Such an intriguing 'molecular double-wheel' form is stabilized by substantially enhanced interlayer covalent bonding associated with strong s-d hybridization. Similar A-A stacking is also observed in the ground states or low-lying isomers of the clusters composed of other hcp elements, such as Os, Tc, Re, and Co. Note that these 'molecular double-wheels' show enhanced chemical activity toward H{sub 2}O splitting relative to their bulk counterpart, implying its potential applications as nanocatalysts.

  17. AAS and spectrophotometric methods for the determination metoprolol tartrate in tablets

    NASA Astrophysics Data System (ADS)

    Alpdoğan, Güzin; Sungur, Sidika

    1999-11-01

    Sensitive and specific atomic adsorption spectroscopy (AAS) and spectrophotometric methods have been developed for the determination of beta adrenergic blocking drug, metoprolol tartrate.The method is based on the formation of Cu(II) dithiocarbamate complex by derivatization of the secondary amino group of metoprolol with CS 2 and CuCl 2 in the presence of ammonia.The copper-bis(dithiocarbamate) complex was extracted into chloroform and the concentration of metoprolol tartrate was determined directly by spectrophotometric and indirectly by AAS measurement of copper.The two methods developed were applied to the assay of metoprolol tartrate in commercial tablet formulations.The methods were compared statistically with each other and with the high performance liquid chromatography (HPLC) method of USPXXII using t- and F-tests.

  18. The Disk and Jet of the Classical T Tauri Star AA Tau

    NASA Technical Reports Server (NTRS)

    Cox, A. W.; Grady, C. A.; Hamel, H.; Hornbeck, Jeremy; Russell, R.; Sitko, M.; Woodgate, B.

    2013-01-01

    Previous studies of the classical T Tauri star AA Tau have interpreted the UX Orionis-like photopolarimetric variability as being due to a warp in the inner disk caused by an inclined stellar magnetic dipolefield. We test that these effects are macroscopically observable in the inclination and alignment of the disk. We use the HST/STIS coronagraphic detection of the disk to measure the outer disk radius and inclination, and find that the inner disk is both misinclined and misaligned with respect to the outer disk. AA Tau drives a faint jet which is also misaligned with respect to the projection of the outer disk minor axis. The jet is also poorly collimated near the star. The measured inclination, 71+/-1deg, is above the inclination range suggested for stars with UX Orionis-like variability, indicating that dust grains in the disk have grown and settled toward the disk midplane.

  19. Aplastic Anemia & MDS International Foundation (AA&MDSIF): Bone Marrow Failure Disease Scientific Symposium 2014.

    PubMed

    Visconte, Valeria; Lindsley, R Coleman; Berlyne, Deborah

    2015-01-01

    Bone marrow failure syndromes (BMFS) are characterized by a failure of the hematopoietic stem cells to produce adequate blood cells, resulting in either cytopenia (defect in one or more blood cell lineages) or pancytopenia (defect in all blood cell lineages). BMFS can be inherited or acquired. The pathogenesis of these diseases is very heterogeneous. Research efforts have been made all over the world to improve the basic knowledge of these diseases. The Aplastic Anemia and MDS International Foundation (AA&MDSIF) is an independent nonprofit organization whose mission is to help patients and family members cope with BMFS. Here, we summarize novel scientific discoveries in several BMFS that were presented at the 4th International Bone Marrow Failure Disease Scientific Symposium 2014 that AA&MDSIF sponsored on March 27-28, 2014, in Rockville, MD.

  20. Effects of simulated ice on the performance of price type-AA current meter rotors

    USGS Publications Warehouse

    Fulford, Janice M.

    1994-01-01

    Slush ice readily adheres to the standard metal rotor of the winter Price type-AA current meter and affects the ability of the meter to measure the flow velocity accurately. Tests conducted at the U.S. Geological Survey Hydraulics Laboratory at Stennis Space Center, Mississippi, attempt to quantify the effects of slush ice on the performance of standard Price type-AA meter metal rotors. Test data obtained for rotors filled with simulated slush are compared with data for solid-cup polymer and standard hollow-cup metal rotors. Partial filling of the cups only marginally affects rotor performance at velocities greater than 15.24 centimeters per second. However, when cups are filled or over-filled with simulated slush, rotor performance is noticeably affected. Errors associated with slush over-filling and filling of cups are also significant when flows are angled vertically.

  1. External electric field effects on AAS oscillations in narrow gap semiconductors

    NASA Astrophysics Data System (ADS)

    Lillianfeld, R. B.; Kallaher, R. L.; Davis, D. E.; Heremans, J. J.; Chen, Hong; Goel, N.; Chung, S. J.; Santos, M. B.; van Roy, W.; Borghs, G.

    2008-03-01

    We present experiments on quantum interference phenomena in semiconductors with strong spin-orbit interaction, using mesoscopic parallel ring arrays fabricated on InSb/InAlSb and InAs/AlGaSb heterostructures. A front gate modulates the spin-orbit interaction, which in turn affects the oscillatory interference phenomena. The experiments investigate the low temperature resistance of the ring arrays as a function of weak perpendicularly applied magnetic fields as well as applied gate voltage. The low field magnetoresistance in the arrays has the h/2e periodicity characteristic of Altshuler-Aronov-Spivak (AAS) oscillations. Despite reduced gate action typical of narrow-gap heterostructures (characterized by Hall measurements), we note an effect on the oscillatory magnetoresistance. The AAS oscillation magnitudes acquire a quasi-periodic modulation as function of gate voltage, and the localization background broadens at higher electron densities. The nature of these influences is examined. (NSF DMR-0618235, DMR-0080054, DMR-0209371)

  2. Spin interference controlled by electric field: Ensemble average effect on AAS and AB oscillation amplitudes

    NASA Astrophysics Data System (ADS)

    Nitta, Junsaku; Bergsten, Tobias

    2008-03-01

    Time reversal symmetric Al’tshuler-Aronov-Spivak (AAS) oscillations are measured in an array of InGaAs mesoscopic loops. We confirm that gate voltage dependence of h/2 e period oscillations is due to spin interference from the effect of ensemble average on the AAS and Aharonov-Bohm (AB) amplitudes. This spin interference is based on the time reversal Aharonov-Casher (AC) effect. The AC interference oscillations are controlled over several periods. This result shows evidence for electrical manipulation of the spin precession angle in an InGaAs two-dimensional electron gas channel. We control the precession rate in a precise and predictable way with an electrostatic gate.

  3. Toothpaste lava: Characteristics and origin of a lava structural type transitional between pahoehoe and aa

    NASA Astrophysics Data System (ADS)

    Rowland, Scott K.; Walker, George P. L.

    1987-08-01

    Toothpaste lava, an important basalt structural type which illustrates the transition from pahoehoe to aa, is particularly well displayed on the 1960 Kapoho lava of Kilauea Volcano. Its transitional features stem from a viscosity higher than that of pahoehoe and a rate of flow slower than that of aa. Viscosity can be quantified by the limited settling of olivine phenocrysts and rate of flow by field observations related to the low-angle slope on which the lava flowed. Much can be learned about the viscosity, rheologic condition, and flow velocity of lavas long after solidification by analyses of their structural characteristics, and it is possible to make at least a semiquantitative assessment of the numerical values of these parameters.

  4. Dry Sliding Tribological Studies of AA6061-B4C-Gr Hybrid Composites

    NASA Astrophysics Data System (ADS)

    Monikandan, V. V.; Joseph, M. A.; Rajendrakumar, P. K.

    2016-10-01

    The dry sliding behavior of stir-cast AA6061-10 wt.% B4C composites containing 2.5, 5 and 7.5 wt.% graphite particles was studied as a function of applied load, sliding speed and sliding distance on a pin-on-disk tribotester. The wear rate and friction coefficient increased with increase in applied load and sliding distance. The increase in graphite addition reduced the increase in wear rate and friction coefficient in the sliding speed range 2-2.5 m/s. Scanning electron microscopy of the worn pin revealed a graphite tribolayer, and transmission electron microscopy revealed overlapping deformation bands under 30 N applied load. Upon increasing the applied load to 40 N, welded region with fine crystalline structure was formed due to dynamic recrystallization of AA6061 alloy matrix.

  5. Edge Fracture Prediction ofTraditional and Advanced Trimming Processes for AA6111-T4 Sheets

    SciTech Connect

    Hu, Xiaohua; Choi, Kyoo Sil; Sun, Xin; Golovashchenko, Segey F.

    2014-02-15

    This work examines the traditional and advanced trimming of AA6111-T4 aluminum sheets with finite element simulations. The Rice-Tracy damage model is used for the simulation with damage parameters estimated from experimental observation of grain aspect ratio near the fracture surface of trimmed parts. Fine meshes at the shearing zone, adaptive meshing, and adaptive contact techniques are used to accurately capture the contact interactions between the sharp corner of the trimming tools and the blank to be trimmed. To the knowledge of the authors, these are the first trimming simulations that can predict the effects of shearing clearance on burr heights with quantitative accuracy for AA6111-T4 aluminum sheets. In addition, the models have also accurately reproduced the crack initiation site as well as burr and sliver formation mechanisms observed experimentally.

  6. Prospects for Quarkonium Measurements in p-A and A-A Collisions at the LHC

    NASA Astrophysics Data System (ADS)

    Winn, Michael

    2017-03-01

    The potential of the ALICE, ATLAS, CMS and LHCb detectors for the measurement of quarkonium in heavy-ion collisions, both in nucleus-nucleus (A-A) and in proton-nucleus (p-A) interactions, in the years 2015 until about 2030 in the LHC Runs 2, 3 and 4 with larger statistics and detector upgrades is described. A selection of newly available observables is discussed.

  7. EDP Sciences and A&A: partnering to providing services to support the scientific community

    NASA Astrophysics Data System (ADS)

    Henri, Agnes

    2015-08-01

    Scholarly publishing is no longer about simply producing and packaging articles and sending out to subscribers. To be successful, as well as being global and digital, Publishers and their journals need to be fully engaged with their stakeholders (authors, readers, funders, libraries etc), and constantly developing new products and services to support their needs in the ever-changing environment that we work in.Astronomy & Astrophysics (A&A) is a high quality, major international Journal that belongs to the astronomical communities of a consortium of European and South American countries supported by ESO who sponsor the journal. EDP Sciences is a non-profit publisher belonging to several learned societies and is appointed by ESO to publish the journal.Over the last decade, as well as publishing the results of worldwide astronomical and astrophysical research, A&A and EDP Sciences have worked in partnership to develop a wide range of services for the authors and readers of A&A:- A specialist language editing service: to provide a clear and excellent level of English ensuring full understanding of the high-quality science.- A flexible and progressive Open Access Policy including Gold and Green options and strong links with arXiv.- Enriched articles: authors are able to enhance their articles using a wide range of rich media such as 3D models, videos and animations.Multiple publishing formats: allowing readers to browse articles on multiple devices including eReaders and Kindles.- “Scientific Writing for Young Astronomers”: In 2008 EDP Sciences and A&A set up the Scientific Writing for Young Astronomers (SWYA) School with the objective to teach early PhD Students how write correct and efficient scientific papers for different mediums (journals, proceedings, thesis manuscripts, etc.).

  8. Corrosion Susceptibility of AA5083-H116 in Biologically Active Atmospheric Marine Environments

    DTIC Science & Technology

    2014-03-01

    by the standardized nitric acid test ASTM G67." Fatigue and stress corrosion cracking behaviors of sensitized AA5083 have also been evaluated.1213... acid (NAMLT Test)," ASTM Hanbook 3.02 Corrosion of Metals; Wear and Erosion. ASTM Hanbook 3.02 Corrosion of Metals; Wear and Erosion (ASTM...DATE (DD-MM-YYYY) 12-05-2014 REPORT TYPE Conference Proceeding (refereed) 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Corrosion

  9. Environmentally Assisted Cracking Properties of AA7249 Extrusions for Aerospace Applications

    DTIC Science & Technology

    2007-11-02

    USNA Chemistry Department for allowing me access to their DSC unit. Dr. Iulian Gheorghe ( ALU Menziken Aerospace / Universal Alloy Corporation) not...that environmental attacks is now becoming a significant concern. Structural components in the P-3C are currently composed of aluminum alloy AA7075-T6...effects of processing on wide panel extrusions. The results of this study will contribute to the ongoing evaluation of these alloys for replacement

  10. On the Study of the Sheet Bendability in AA5754-O Temper Alloy

    NASA Astrophysics Data System (ADS)

    Shi, Y.; Jin, H.; Wu, P. D.; Lloyd, D. J.

    2016-10-01

    The bendability of AA5754 aluminum alloy in fully recrystallized temper (O temper) has been studied. Both experimental and numerical work showed that a strong {001}<100> Cube crystallographic texture in the sheet provides improved bendability compared with a low Cube texture sheet, even though the tensile properties of both sheets are similar. A crystal-based finite element model also showed that the textural distribution influences bendability, while the initial surface topography has little effect.

  11. Microstructure Characterization of Magnetic-Pulse-Welded AA 6061-T6 by Electron Backscattered Diffraction

    SciTech Connect

    Zhang, Yuan; Babu, Suresh; Zhang, P; Kenik, Edward A; Daehn, Glenn

    2008-01-01

    The grain boundary crystallographic misorientations of magnetic-pulse-welded (MPW) aluminum alloy (AA) 6061-T6 in linear and tubular configurations were examined using the electron backscattered diffraction (EBSD) technique. A refined structure of heavily deformed grains with higher grain boundary angles was observed in linear welds. Significant spalling was observed away from the joints, in the interior of tubular welds. The results show the complex interaction of shock waves with the materials during this impact welding process.

  12. CtaM Is Required for Menaquinol Oxidase aa3 Function in Staphylococcus aureus

    PubMed Central

    Schurig-Briccio, Lici A.; Gerdes, Svetlana Y.; Gennis, Robert B.

    2016-01-01

    ABSTRACT Staphylococcus aureus is the leading cause of skin and soft tissue infections, bacteremia, osteomyelitis, and endocarditis in the developed world. The ability of S. aureus to cause substantial disease in distinct host environments is supported by a flexible metabolism that allows this pathogen to overcome challenges unique to each host organ. One feature of staphylococcal metabolic flexibility is a branched aerobic respiratory chain composed of multiple terminal oxidases. Whereas previous biochemical and spectroscopic studies reported the presence of three different respiratory oxygen reductases (o type, bd type, and aa3 type), the genome contains genes encoding only two respiratory oxygen reductases, cydAB and qoxABCD. Previous investigation showed that cydAB and qoxABCD are required to colonize specific host organs, the murine heart and liver, respectively. This work seeks to clarify the relationship between the genetic studies showing the unique roles of the cydAB and qoxABCD in virulence and the respiratory reductases reported in the literature. We establish that QoxABCD is an aa3-type menaquinol oxidase but that this enzyme is promiscuous in that it can assemble as a bo3-type menaquinol oxidase. However, the bo3 form of QoxABCD restricts the carbon sources that can support the growth of S. aureus. In addition, QoxABCD function is supported by a previously uncharacterized protein, which we have named CtaM, that is conserved in aerobically respiring Firmicutes. In total, these studies establish the heme A biosynthesis pathway in S. aureus, determine that QoxABCD is a type aa3 menaquinol oxidase, and reveal CtaM as a new protein required for type aa3 menaquinol oxidase function in multiple bacterial genera. PMID:27406563

  13. Binding of Cyt1Aa and Cry11Aa toxins of Bacillus thuringiensis serovar israelensis to brush border membrane vesicles of Tipula paludosa (Diptera: Nematocera) and subsequent pore formation.

    PubMed

    Oestergaard, Jesko; Ehlers, Ralf-Udo; Martínez-Ramírez, Amparo C; Real, Maria Dolores

    2007-06-01

    Bacillus thuringiensis serovar israelensis (B. thuringiensis subsp. israelensis) produces four insecticidal crystal proteins (ICPs) (Cry4A, Cry4B, Cry11A, and Cyt1A). Toxicity of recombinant B. thuringiensis subsp. israelensis strains expressing only one of the toxins was determined with first instars of Tipula paludosa (Diptera: Nematocera). Cyt1A was the most toxic protein, whereas Cry4A, Cry4B, and Cry11A were virtually nontoxic. Synergistic effects were recorded when Cry4A and/or Cry4B was combined with Cyt1A but not with Cry11A. The binding and pore formation are key steps in the mode of action of B. thuringiensis subsp. israelensis ICPs. Binding and pore-forming activity of Cry11Aa, which is the most toxic protein against mosquitoes, and Cyt1Aa to brush border membrane vesicles (BBMVs) of T. paludosa were analyzed. Solubilization of Cry11Aa resulted in two fragments, with apparent molecular masses of 32 and 36 kDa. No binding of the 36-kDa fragment to T. paludosa BBMVs was detected, whereas the 32-kDa fragment bound to T. paludosa BBMVs. Only a partial reduction of binding of this fragment was observed in competition experiments, indicating a low specificity of the binding. In contrast to results for mosquitoes, the Cyt1Aa protein bound specifically to the BBMVs of T. paludosa, suggesting an insecticidal mechanism based on a receptor-mediated action, as described for Cry proteins. Cry11Aa and Cyt1Aa toxins were both able to produce pores in T. paludosa BBMVs. Protease treatment with trypsin and proteinase K, previously reported to activate Cry11Aa and Cyt1Aa toxins, respectively, had the opposite effect. A higher efficiency in pore formation was observed when Cyt1A was proteinase K treated, while the activity of trypsin-treated Cry11Aa was reduced. Results on binding and pore formation are consistent with results on ICP toxicity and synergistic effect with Cyt1Aa in T. paludosa.

  14. Parametric studies on tensile strength in joining AA6061- T6 and AA7075-T6 by gas metal arc welding process

    NASA Astrophysics Data System (ADS)

    Ishak, M.; Noordin, N. F. M.; Shah, L. H.

    2015-12-01

    Proper selection of the welding parameters can result in better joining. In this study, the effects of various welding parameters on tensile strength in joining dissimilar aluminum alloys AA6061-T6 and AA7075-T6 were investigated. 2 mm thick samples of both base metals were welded by semi-automatic gas metal arc welding (GMAW) using filler wire ER5356. The welding current, arc voltage and welding speed were chosen as variables parameters. The strength of each specimen after the welding operations were tested and the effects of these parameters on tensile strength were identified by using Taguchi method. The range of parameter for welding current were chosen from 100 to 115 A, arc voltage from 17 to 20 V and welding speed from 2 to 5 mm/s. L16 orthogonal array was used to obtained 16 runs of experiments. It was found that the highest tensile strength (194.34 MPa) was obtained with the combination of a welding current of 115 A, welding voltage of 18 V and welding speed of 4 mm/s. Through analysis of variance (ANOVA), the welding voltage was the most effected parameter on tensile strength with percentage of contribution at 41.30%.

  15. Mechanical and microstructural characterization of single and double pass Aluminum AA6061 friction stir weld joints

    NASA Astrophysics Data System (ADS)

    Othman, N. H.; Shah, L. H.; Ishak, M.

    2015-12-01

    This study focuses on the effect of single pass (SP), double sided pass (DSP) and normal double pass (NDP) method on friction stir welding of aluminum AA6061. Two pieces of AA6061 alloy with thickness of 6 mm were friction stir welded by using conventional milling machine. The rotational speeds that were used in this study were 800 rpm, 1000 rpm and 1200 rpm, respectively. The welding speed is fixed to 100 mm/min. Microstructure observation of welded area was studied by using optical microscope. Tensile test and Vickers hardness test were used to evaluate the mechanical properties of this specimen. Mechanical property analysis results indicate that at low rotational speeds, defects such as surface lack of fill and tunneling in the welded area can be observed. Vickers hardness of specimens however did not vary much when rotational speed is varied. Welded specimens using single pass method shows higher tensile strength and hardness value compared to both double pass methods up to 180.61 MPa. Moreover, DSP showed better tensile test and hardness test compared to NDP method. The optimum parameters were found to be single pass method with 1200 rpm of rotational speed. Therefore economically sound to only perform SP method to obtain maximum tensile strength for AA6061 FSW with thickness of 6 mm.

  16. Challenging In-Situ Strain Measurement In Pneumatic Bulging Of AA5083

    NASA Astrophysics Data System (ADS)

    Liewald, M.; Kappes, J.

    2011-05-01

    Superplastic forming of sheet metal aluminum alloys exhibits numerous technical and economical advantages for manufacturing of complex part geometries in niche type production. For virtual engineering tasks prior manufacturing of superplastic forming equipment such as forming dies, numerical sheet metal forming simulations and material parameters are crucial. In such context the selected testing procedure should be as similar as possible to the subsequent forming technique. For that reason the pneumatic bulge test represents an appropriate testing procedure for the most common superplastic forming process—the blow forming process. In-situ strain measurement of pneumatic bulging AA5083 at 500° C results in high requirements in terms of the grid applied on the blank surface due to process temperature and large strain values. These large strain values result into pole heights up to 70 mm of the bulge test specimens using an initial blank thickness of 1.5 mm and a circular die opening of 100 mm. This paper describes the influence of different grid types and finally proposes adequate grid types for in-situ strain measurement for pneumatic bulging of AA5083. Furthermore the capabilities of in-situ measurement of strains during pneumatic bulging of AA5083 are highlighted.

  17. Optimizing friction stir welding parameters to maximize tensile strength of AA2219 aluminum alloy joints

    NASA Astrophysics Data System (ADS)

    Babu, S.; Elangovan, K.; Balasubramanian, V.; Balasubramanian, M.

    2009-04-01

    AA2219 aluminium alloy (Al-Cu-Mn alloy) has gathered wide acceptance in the fabrication of lightweight structures requiring a high strength-to-weight ratio and good corrosion resistance. In contrast to the fusion welding processes that are routinely used for joining structural aluminium alloys, the friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force etc., and the tool pin profile play a major role in determining the joint strength. An attempt has been made here to develop a mathematical model to predict the tensile strength of friction stir welded AA2219 aluminium alloy by incorporating FSW process parameters. A central composite design with four factors and five levels has been used to minimize the number of experimental conditions. The response surface method (RSM) has been used to develop the model. The developed mathematical model has been optimized using the Hooke and Jeeves search technique to maximize the tensile strength of the friction stir welded AA2219 aluminium alloy joints.

  18. Interlayer vacancy defects in AA-stacked bilayer graphene: Density functional theory predictions.

    PubMed

    Vuong, Amanda; Trevethan, Tom; Latham, Christopher; Ewels, Chris; Erbahar, Doğan; Briddon, Patrick; Rayson, Mark; Heggie, Malcolm

    2017-02-09

    AA-stacked graphite and closely related structures, where carbon atoms are located in registry in adjacent graphene layers, are a feature of graphitic systems including twisted and folded bilayer graphene, and turbostratic graphite. We present the results of ab initio density functional theory calculations performed to investigate the complexes that are formed from the binding of vacancy defects across neighbouring layers in AA-stacked bilayers. As with AB stacking, the carbon atoms surrounding lattice vacancies can form interlayer structures with sp2 bonding that are lower in energy than in-plane reconstructions. The sp2 interlayer bonding of adjacent multivacancy defects in registry creates a type of stable sp2 bonded 'wormhole' or tunnel defect between the layers. We also identify a new class of 'mezzanine' structure characterised by sp3 interlayer bonding, resembling a prismatic vacancy loop. The V6 hexavacancy variant, where six sp3 carbon atoms sit midway between two carbon layers and bond to both, is substantially more stable than any other vacancy aggregate in AA-stacked layers. Our focus is on vacancy generation and aggregation in the absence of extreme temperatures or intense beams.

  19. New variants of lepidoptericidal toxin genes encoding Bacillus thuringiensis Vip3Aa proteins.

    PubMed

    Sauka, Diego H; Rodriguez, Sonia E; Benintende, Graciela B

    2012-01-01

    Bacillus thuringiensis is an entomopathogenic bacterium characterized by producing parasporal proteinaceous insecticidal crystal inclusions during sporulation. Many strains are capable of also expressing other insecticidal proteins called Vip during the vegetative growing phase. Particularly, Vip3A proteins have activity against certain Lepidoptera species through a unique mechanism of action which emphasized their possible use in resistance management strategies against resistant pests. The aim of the work was to develop a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method that can distinguish between vip3A genes from B. thuringiensis strains. In addition, 4 novel vip3Aa genes were cloned and sequenced. The method was originally based on amplification of a single PCR amplicon and the use of 2 restriction enzymes with recognition sites that facilitate simultaneous detection. Subsequently, a third restriction enzyme was used to distinguish between vip3A variants. Thirteen vip3Aa genes were identified in strains belonging to 10 different B. thuringiensis serovars. Three intra-subclass variants of vip3Aa genes could be differentiated. The presented method can serve as an invaluable tool for the investigation of known and novel vip3A genes in B. thuringiensis strains. To the best of our knowledge, this is the first report where variants of a same subclass of insecticidal genes could be distinguished following PCR-RFLP.

  20. Interlayer vacancy defects in AA-stacked bilayer graphene: density functional theory predictions

    NASA Astrophysics Data System (ADS)

    Vuong, A.; Trevethan, T.; Latham, C. D.; Ewels, C. P.; Erbahar, D.; Briddon, P. R.; Rayson, M. J.; Heggie, M. I.

    2017-04-01

    AA-stacked graphite and closely related structures, where carbon atoms are located in registry in adjacent graphene layers, are a feature of graphitic systems including twisted and folded bilayer graphene, and turbostratic graphite. We present the results of ab initio density functional theory calculations performed to investigate the complexes that are formed from the binding of vacancy defects across neighbouring layers in AA-stacked bilayers. As with AB stacking, the carbon atoms surrounding lattice vacancies can form interlayer structures with sp 2 bonding that are lower in energy than in-plane reconstructions. The sp 2 interlayer bonding of adjacent multivacancy defects in registry creates a type of stable sp 2 bonded ‘wormhole’ or tunnel defect between the layers. We also identify a new class of ‘mezzanine’ structure characterised by sp 3 interlayer bonding, resembling a prismatic vacancy loop. The V 6 hexavacancy variant, where six sp 3 carbon atoms sit midway between two carbon layers and bond to both, is substantially more stable than any other vacancy aggregate in AA-stacked layers. Our focus is on vacancy generation and aggregation in the absence of extreme temperatures or intense beams.

  1. Simultaneous Optical Spectroscopic Measurement of Hemoglobin and Myoglobin Saturations and Cytochrome aa3 Oxidation In Vivo

    PubMed Central

    Arakaki, Lorilee S. L.; Ciesielski, Wayne A.; Thackray, Brett D.; Feigl, Eric O.; Schenkman, Kenneth A.

    2015-01-01

    A method to simultaneously measure oxygenation in vascular, intracellular, and mitochondrial spaces from optical spectra acquired from muscle has been developed. In order to validate the method, optical spectra in the visible and near infrared regions (600–850 nm) were acquired from solutions of myoglobin, hemoglobin, and cytochrome oxidase that included Intralipid as a light scatterer. Spectra were also acquired from the rabbit forelimb during ischemia. Three partial least squares (PLS) analyses were performed on second-derivative spectra, each separately calibrated to myoglobin saturation, hemoglobin saturation, or cytochrome aa3 oxidation. The three variables were measured from in vitro and in vivo spectra that contained all three chromophores. In the in vitro studies, measured values of myoglobin saturation, hemoglobin saturation, and cytochrome aa3 oxidation had standard errors of 7.4%, 3.8%, and 3.9%, respectively, with little cross-talk between the measurements. During ischemia in the rabbit forelimb, hemoglobin desaturated first, followed by myoglobin, while cytochrome aa3 reduction occurred last. The ability to simultaneously measure oxygenations in the vascular, intracellular, and mitochondrial compartments will be valuable in physiological studies of muscle metabolism and in clinical studies when oxygen supply or utilization are compromised. PMID:20828433

  2. What Astronomers and the AAS Need to be Doing to Curb Light Pollution

    NASA Astrophysics Data System (ADS)

    Green, D. W. E.

    2001-12-01

    Astronomers and especially the AAS are doing apalling little in the war on light pollution. This is quite surprising, considering that optical groundbased astronomy may become nearly extinct in the 21st century if we don't get more serious about the loss of our night skies to artificial lighting. Part of the blame must be placed on astronomers throughout the 20th century (particularly before 1980), as very few of them seem to have set an example by starting an early crusade against bad outdoor night lighting (save for a handful of important individuals near large U.S. observatories, and a few connected with smaller observatories); this apathy of earlier generations of astronomers fueled the current general apathy within the AAS and aided the opening of the floodgates in terms of the disastrous lighting situation now upon us in terms of drowning out the night sky. There are possible solutions, and they need to be discussed and acted upon quickly. For example, the AAS should require that all members include a useful amount (say, \\$30) in annual membership fees to be directly transmitted to the International Dark Sky Association, and the AAS should make constant visible strides to educate the public and government officials of the absolute need to reduce outdoor lighting levels and to fully shield all outdoor lighting. There are many other areas of research into outdoor lighting that the AAS should fund or officially/strongly support, so that the astronomical community can better be educated (and can better educate the public) on the evils of bad and thoughtless outdoor-lighting practices; such research includes developing a comprehensive database of national statistics on numbers and types of different outdoor lamps, as a function of time (thus, historical), and also a comprehensive database including all local, state, and federal lighting laws and ordinances together with legal court cases (and their outcomes) involving outdoor night lighting. And professional

  3. CSI 2264: Probing the inner disks of AA Tauri-like systems in NGC 2264

    NASA Astrophysics Data System (ADS)

    McGinnis, P. T.; Alencar, S. H. P.; Guimarães, M. M.; Sousa, A. P.; Stauffer, J.; Bouvier, J.; Rebull, L.; Fonseca, N. N. J.; Venuti, L.; Hillenbrand, L.; Cody, A. M.; Teixeira, P. S.; Aigrain, S.; Favata, F.; Fűrész, G.; Vrba, F. J.; Flaccomio, E.; Turner, N. J.; Gameiro, J. F.; Dougados, C.; Herbst, W.; Morales-Calderón, M.; Micela, G.

    2015-05-01

    Context. The classical T Tauri star (CTTS) AA Tau has presented photometric variability that was attributed to an inner disk warp, caused by the interaction between the inner disk and an inclined magnetosphere. Previous studies of the young cluster NGC 2264 have shown that similar photometric behavior is common among CTTS. Aims: The goal of this work is to investigate the main causes of the observed photometric variability of CTTS in NGC 2264 that present AA Tau-like light curves, and verify if an inner disk warp could be responsible for their observed variability. Methods: In order to understand the mechanism causing these stars' photometric behavior, we investigate veiling variability in their spectra and u - r color variations and estimate parameters of the inner disk warp using an occultation model proposed for AA Tau. We also compare infrared Spitzer IRAC and optical CoRoT light curves to analyze the dust responsible for the occultations. Results: AA Tau-like variability proved to be transient on a timescale of a few years. We ascribe this variability to stable accretion regimes and aperiodic variability to unstable accretion regimes and show that a transition, and even coexistence, between the two is common. We find evidence of hot spots associated with occultations, indicating that the occulting structures could be located at the base of accretion columns. We find average values of warp maximum height of 0.23 times its radial location, consistent with AA Tau, with variations of on average 11% between rotation cycles. We also show that extinction laws in the inner disk indicate the presence of grains larger than interstellar grains. Conclusions: The inner disk warp scenario is consistent with observations for all but one star with AA Tau-like variability in our sample. AA Tau-like systems are fairly common, comprising 14% of CTTS observed in NGC 2264, though this number increases to 35% among systems of mass 0.7 M⊙ ≲ M ≲ 2.0 M⊙. Assuming random

  4. Baseline susceptibility and monitoring of Brazilian populations of Spodoptera frugiperda (Lepidoptera: Noctuidae) and Diatraea saccharalis (Lepidoptera: Crambidae) to Vip3Aa20 insecticidal protein.

    PubMed

    Bernardi, Oderlei; Amado, Douglas; Sousa, Renan S; Segatti, Fabiana; Fatoretto, Julio; Burd, Anthony D; Omoto, Celso

    2014-04-01

    The genetically modified maize expressing Vip3Aa20 insecticidal protein from Bacillus thuringiensis Berliner is abiotechnological option for the control of Spodoptera frugiperda (J.E. Smith) and Diatraea saccharalis (F.) in Brazil. To support an Insect Resistance Management program, we conducted studies of baseline susceptibility and monitoring of Brazilian populations of S. frugiperda and D. saccharalis to the Vip3Aa20 insecticidal protein. Neonates were exposed to Vip3Aa20 applied on artificial diet surface. Mortality and growth inhibition were assessed after 7 d. All populations were susceptible to Vip3Aa20. The LC50 ranged from 92.38 to 611.65 ng Vip3Aa20/cm2 for 16 populations of S. frugiperda (6.6-fold variation), and between 61.18 and 367.86 ng Vip3Aa20/cm2 for 6 populations of D. saccharalis (sixfold variation). The EC50 ranged from 21.76 to 70.09 and 48.65 to 163.60 ng Vip3Aa20/cm2 for S. frugiperda and D. saccharalis, respectively. There was a low interpopulation variation in susceptibility to Vip3Aa20, which represents the natural geographic variation in the response, and not the variation caused by previous exposure to selection pressure. For these two pests, the diagnostic concentrations of 2,000 and 3,600 ng of Vip3Aa20/cm2 caused high mortality. These diagnostic concentrations will be used in resistance monitoring programs in Brazil.

  5. Residue-specific force field based on the protein coil library. RSFF1: modification of OPLS-AA/L.

    PubMed

    Jiang, Fan; Zhou, Chen-Yang; Wu, Yun-Dong

    2014-06-26

    Traditional protein force fields use one set of parameters for most of the 20 amino acids (AAs), allowing transferability of the parameters. However, a significant shortcoming is the difficulty to fit the Ramachandran plots of all AA residues simultaneously, affecting the accuracy of the force field. In this Feature Article, we report a new strategy for protein force field parametrization. Backbone and side-chain conformational distributions of all 20 AA residues obtained from protein coil library were used as the target data. The dihedral angle (torsion) potentials and some local nonbonded (1-4/1-5/1-6) interactions in OPLS-AA/L force field were modified such that the target data can be excellently reproduced by molecular dynamics simulations of dipeptides (blocked AAs) in explicit water, resulting in a new force field with AA-specific parameters, RSFF1. An efficient free energy decomposition approach was developed to separate the corrections on ϕ and ψ from the two-dimensional Ramachandran plots. RSFF1 is shown to reproduce the experimental NMR (3)J-coupling constants of AA dipeptides better than other force fields. It has a good balance between α-helical and β-sheet secondary structures. It can successfully fold a set of α-helix proteins (Trp-cage and Homeodomain) and β-hairpins (Trpzip-2, GB1 hairpin), which cannot be consistently stabilized by other state-of-the-art force fields. Interestingly, the RSFF1 force field systematically overestimates the melting temperature (and the stability of native state) of these peptides/proteins. It has a potential application in the simulation of protein folding and protein structure refinement.

  6. The localization of the Golgin GCC185 is independent of Rab6A/A' and Arl1.

    PubMed

    Houghton, Fiona J; Chew, Pau Ling; Lodeho, Sylvain; Goud, Bruno; Gleeson, Paul A

    2009-08-21

    Mammalian golgins of the trans-Golgi network (TGN) are small G protein effectors that are required for membrane transport and contain a Golgi targeting C-terminal GRIP domain. The localization of two TGN golgins, p230/golgin-245 and golgin-97, is mediated by the small GTPase Arl1, whereas recruitment of the TGN golgin GCC185 is controversial. Recently, GCC185 was proposed to localize to the Golgi by the co-operation of two small GTPases, Rab6A/A' and Arl1 (Burguete et al., 2008), a model based predominantly on in vitro interactions. Here we demonstrate that Golgi recruitment of endogenous GCC185 does not involve Rab6A/A' and Arl1. We find minimal colocalization between Rab6A/A' and endogenous GCC185 on Golgi membranes and failed to detect an interaction between Rab6A/A' and C-terminal domains of GCC185 by yeast two-hybrid analyses. Moreover, depletion of both Rab6A/A' and Arl1 also had no effect on the localization of endogenous GCC185 or the isolated GRIP domain of GCC185.

  7. Effects of water chemistry on decolorization in three photochemical processes: Pro and cons of the UV/AA process.

    PubMed

    Wu, Bingdang; Yin, Ran; Zhang, Guoyang; Yu, Chao; Zhang, Shujuan

    2016-11-15

    The poor selectivity of hydroxyl radicals is a major restriction in the practical application of the UV/H2O2 process for dyeing wastewater treatment. As an alternative, the target-selective UV/acetylacetone (AA) process was found highly efficient for dye decolorization. For the proper selection and application of the two photochemical processes, the effects of water matrices, including common inorganic anions (Cl(-), SO4(2-), NO3(-), HCO3(-)), natural organic matter, metal cations (Mg(2+), Mn(2+), Cu(2+), Fe(3+), Cr(3+)), and temperature, on the photo-degradation of an azo dye, Acid Orange 7 (AO7), were systematically investigated. The experimental results demonstrate that the UV/AA process was more sensitive to inner filter effect. NO3(-), Cu(2+), and Fe(3+) were all detrimental to the UV/AA process, whereas at certain concentrations they were beneficial to the UV/H2O2 process. However, even with severe inhibitory effects, the decolorization efficiency of the UV/AA process was still several times higher than that of the UV/H2O2 process. The results are helpful for us to better understand the mechanisms behind the UV/AA process and may shed light on the application of UV-based advanced oxidation processes for wastewater treatment.

  8. Studies on cytochrome c oxidase activity of the cytochrome c1aa3 complex from Thermus thermophilus.

    PubMed

    Yoshida, T; Fee, J A

    1984-01-25

    Cytochrome oxidase from T. thermophilus is isolated as a noncovalent complex of cytochromes c1 and aa3 in which the four redox components of aa3 appear to be associated with a single approximately 55,000-D subunit while the heme C is associated with a approximately 33,000-D peptide (Yoshida, T., Lorence, R. M., Choc, M. G., Tarr, G. E., Findling, K. L., and Fee, J. A. (1983) J. Biol. Chem. 258, 112-123). We have examined the steady state transfer of electrons from ascorbate to oxygen by cytochrome c1aa3 as mediated by horse heart, Candida krusei, and T. thermophilus (c552) cytochromes c as well as tetramethylphenylenediamine (TMPD). These mediators exhibit simple Michaelis-Menten kinetic behavior yielding Vmax and KM values characteristic of the experimental conditions. Three classes of kinetic behavior were observed and are qualitatively discussed in terms of a reaction scheme. The data show that tetramethylphenyldiamine and cytochromes c react with the enzyme at independent sites; it is suggested that cytochrome c1 may efficiently transfer electrons to cytochrome aa3. When incorporated into phospholipid vesicles, the highly purified cytochrome c1aa3 was found to translocate one proton into the exterior medium for each molecule of cytochrome c552 oxidized. The combined results suggest that this bacterial enzyme functions in a manner generally identical with the more complex eucaryotic enzyme.

  9. Is the serum amyloid A protein in acute phase plasma high density lipoprotein the precursor of AA amyloid fibrils?

    PubMed Central

    Baltz, M L; Rowe, I F; Caspi, D; Turnell, W G; Pepys, M B

    1986-01-01

    Serum amyloid A protein (SAA), an apolipoprotein of high density lipoprotein (HDL), is generally considered to be the precursor of AA protein, which forms the fibrils in reactive systemic amyloidosis in man and animals. This view is based on amino acid sequence identity between AA and the amino-terminal portion of SAA. However, in extensive and well-controlled studies of experimentally induced murine AA amyloidosis, we were unable to demonstrate a direct precursor-product relationship between SAA, in SAA-rich HDL preparations from acute phase or amyloidotic mouse or human serum, and AA protein in the amyloid deposits. This raises the possibility that SAA in its usual form, as an apolipoprotein of HDL synthesized during the acute phase response, may not be the major precursor of AA fibrils. The amyloidogenic forms of circulating SAA molecules may not be isolated during the preparation of HDL. Alternatively, particularly in the light of recent evidence that SAA mRNA is expressed in many different tissues throughout the body of appropriately stimulated animals, amyloidogenic SAA may be derived from sources other than the liver cells in which SAA-rich HDL is synthesized. PMID:3105937

  10. Toxicity, activation process, and histopathological effect of Bacillus thuringiensis vegetative insecticidal protein Vip3Aa16 on Tuta absoluta.

    PubMed

    Sellami, Sameh; Cherif, Maroua; Abdelkefi-Mesrati, Lobna; Tounsi, Slim; Jamoussi, Kaïs

    2015-02-01

    Tuta absoluta is a destructive moth of Solanaceae plants and especially tomatoes. Here, we considered the entomopathogenic activity of the Bacillus thuringiensis Vip3Aa16 protein heterologously produced by Escherichia coli against T. absoluta. Purified Vip3Aa16 showed lower lethal concentration 50 % against third instar larvae (Toxin/tomato leaf) (335 ± 17 ng/cm(2)) compared to that of B. thuringiensis kurstaki HD1 δ-endotoxins (955 ± 4 ng/cm(2)) (P < 0.05). Action mode examination showed that Vip3Aa16 (88 kDa) was more sensitive to proteolysis activation by the chymotrypsin than the trypsin or the larvae gut soluble proteases, yielding derivative proteins essentially of about 62 and 33 kDa. The gut-soluble proteases could contain trypsin-like enzymes implicated in Vip3Aa16 activation since the proteolysis was inhibited using specific protease inhibitors. Additionally, we showed that the histopathological effect of Vip3Aa16 on T. absoluta larva midguts consisted on a microvillus damage and an epithelial cell rupture.

  11. Bacillus thuringiensis Cry3Aa protoxin intoxication of Tenebrio molitor induces widespread changes in the expression of serine peptidase transcripts.

    PubMed

    Oppert, Brenda; Martynov, Alexander G; Elpidina, Elena N

    2012-09-01

    The yellow mealworm, Tenebrio molitor, is a pest of stored grain products and is sensitive to the Bacillus thuringiensis (Bt) Cry3Aa toxin. As digestive peptidases are a determining factor in Cry toxicity and resistance, we evaluated the expression of peptidase transcripts in the midgut of T. molitor larvae fed either a control or Cry3Aa protoxin diet for 24 h (RNA-Seq), or in larvae exposed to the protoxin for 6, 12, or 24 h (microarrays). Cysteine peptidase transcripts (9) were similar to cathepsins B, L, and K, and their expression did not vary more than 2.5-fold in control and Cry3Aa-treated larvae. Serine peptidase transcripts (48) included trypsin, chymotrypsin and chymotrypsin-like, elastase 1-like, and unclassified serine peptidases, as well as homologs lacking functional amino acids. Highly expressed trypsin and chymotrypsin transcripts were severely repressed, and most serine peptidase transcripts were expressed 2- to 15-fold lower in Cry3Aa-treated larvae. Many serine peptidase and homolog transcripts were found only in control larvae. However, expression of a few serine peptidase transcripts was increased or found only in Cry3Aa-treated larvae. Therefore, Bt intoxication significantly impacted the expression of serine peptidases, potentially important in protoxin processing, while the insect maintained the production of critical digestive cysteine peptidases.

  12. The adhesion performance of epoxy coating on AA6063 treated in Ti/Zr/V based solution

    NASA Astrophysics Data System (ADS)

    Zhu, Wen; Li, Wenfang; Mu, Songlin; Yang, Yunyu; Zuo, Xi

    2016-10-01

    An environment-friendly titanium/zirconium/vanadium-based (Ti/Zr/V) conversion coating was prepared on aluminum alloy 6063 (AA6063). The epoxy powder coatings were applied on the AA6063 samples with/without Ti/Zr/V conversion coatings via electrostatic spraying. The morphology and composition of the conversion coating were studied by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. The surface free energy components of AA6063 samples were measured by a static contact angle measuring device with Owens method. The adhesion properties of the epoxy coating on AA6063 treated with different conversion times were evaluated using a pull-off tester. The Ti/Zr/V conversion coating was mainly composed of metal oxide (TiO2, ZrO2, V2O5, Al2O3, etc.), metal fluoride (ZrF4, AlF3, etc.) and metal organic complex. The formation time of this conversion coating was reduced to 50 s. After such surface treatment, the samples' surface roughness was increased and the contact angle with water was decreased. Both the surface free energy and the work of adhesion were increased. The adhesion strength between the epoxy coating and AA6063 was enhanced significantly.

  13. Synergism and Rules of the new Combination drug Yiqijiedu Formulae (YQJD) on Ischemic Stroke based on amino acids (AAs) metabolism

    PubMed Central

    Gao, Jian; Chen, Chang; Chen, Jian-Xin; Wen, Li-Mei; Yang, Geng-Liang; Duan, Fei-Peng; Huang, Zhi-Ying; Li, De-Feng; Yu, Ding-Rong; Yang, Hong-Jun; Li, Shao-Jing

    2014-01-01

    The use of combination drugs is considered to be a promising strategy to control complex diseases such as ischemic stroke. The detection of metabolites has been used as a versatile tool to reveal the potential mechanism of diverse diseases. In this study, the levels of 12 endogenous AAs were simultaneously determined quantitatively in the MCAO rat brain using RRLC-QQQ method. Seven AAs were chosen as the potential biomarkers, and using PLS-DA analysis, the effects of the new combination drug YQJD, which is composed of ginsenosides, berberine, and jasminoidin, on those 7 AAs were evaluated. Four AAs, glutamic acid, homocysteine, methionine, and tryptophan, which changed significantly in the YQJD-treated groups compared to the vehicle groups (P < 0.05), were identified and designated as the AAs to use to further explore the synergism of YQJD. The result of a PCA showed that the combination of these three drugs exhibits the strongest synergistic effect compared to other combination groups and that ginsenosides might play a pivotal role, especially when combined with jasminoidin. We successfully explored the synergetic mechanism of multi-component and provided a new method for evaluating the integrated effects of combination drugs in the treatment of complex diseases. PMID:24889025

  14. Tetracycline-inducible shRNA targeting antisense long non-coding RNA HIF1A-AS2 represses the malignant phenotypes of bladder cancer.

    PubMed

    Chen, Mingwei; Zhuang, Chengle; Liu, Yuchen; Li, Jianfa; Dai, Fen; Xia, Ming; Zhan, Yonghao; Lin, Junhao; Chen, Zhicong; He, Anbang; Xu, Wen; Zhao, Guoping; Guo, Yinglu; Cai, Zhiming; Huang, Weiren

    2016-06-28

    Various studies have indicated that long non-coding RNAs (lncRNAs) play vital roles in the cancer development and progression. LncRNA hypoxia inducible factor 1alpha antisense RNA-2 (HIF1A-AS2) is upregulated in gastric carcinomas and knockdown of HIF1A-AS2 expression by siRNA could inhibit cell proliferation in vitro and tumorigenesis in vivo. Inspired by these observations, we hypothesized that HIF1A-AS2 possibly plays the analogous roles in bladder cancer. In our study, we first reported that HIF1A-AS2 was up-regulated in bladder cancer tissues and cells, and HIF1A-AS2 expression level in bladder cancer tissues is positively associated with advanced clinical pathologic grade and TNM phase. Cell proliferation inhibition, cell migration suppression and apoptosis induction were observed by silencing HIF1A-AS2 in bladder cancer T24 and 5637 cells. Overexpression of HIF1A-AS2 in SV-HUC-1 cells could promote cell proliferation, cell migration and anti-apoptosis. Besides, we utilized the emerging technology of medical synthetic biology to design tetracycline-inducible small hairpin RNA (shRNA) vector which specifically silenced HIF1A-AS2 in a dosage-dependent manner to inhibit the progression of human bladder cancer. In conclusion, our data suggested that HIF1A-AS2 plays oncogenic roles and can be used as a therapeutic target for treating human bladder cancer. Synthetic "tetracycline-on" switch system that quantitatively controlled the expression of HIF1A-AS2 in bladder cancer can inhibit the progression of bladder cancer cells in a dosage-dependent manner. Our findings provide new insights into the role of the lncRNA HIF1A-AS2 in the bladder cancer.

  15. Dopaminergic modulation of reward-guided decision making in alcohol-preferring AA rats.

    PubMed

    Oinio, Ville; Bäckström, Pia; Uhari-Väänänen, Johanna; Raasmaja, Atso; Piepponen, Petteri; Kiianmaa, Kalervo

    2017-03-06

    R**esults from animal gambling models have highlighted the importance of dopaminergic neurotransmission in modulating decision making when large sucrose rewards are combined with uncertainty. The majority of these models use food restriction as a tool to motivate animals to accomplish operant behavioral tasks, in which sucrose is used as a reward. As enhanced motivation to obtain sucrose due to hunger may impact its reward-seeking effect, we wanted to examine the decision-making behavior of rats in a situation where rats were fed ad libitum. For this purpose, we chose alcohol-preferring AA (alko alcohol) rats, as these rats have been shown to have high preference for sweet agents. In the present study, AA rats were trained to self-administer sucrose pellet rewards in a two-lever choice task (one pellet vs. three pellets). Once rational choice behavior had been established, the probability of gaining three pellets was decreased over time (50%, 33%, 25% then 20%). The effect of d-amphetamine on decision making was studied at every probability level, as well as the effect of the dopamine D1 receptor agonist SKF-81297 and D2 agonist quinpirole at probability levels of 100% and 25%. d-Amphetamine increased unprofitable choices in a dose-dependent manner at the two lowest probability levels. Quinpirole increased the frequency of unprofitable decisions at the 25% probability level, and SKF-82197 did not affect choice behavior. These results mirror the findings of probabilistic discounting studies using food-restricted rats. Based on this, the use of AA rats provides a new approach for studies on reward-guided decision making.

  16. Now We Are Ten: The AAS Tenth, Decennial Meeting at Yerkes Observatory in August 1909

    NASA Astrophysics Data System (ADS)

    Osterbrock, D. E.

    1997-12-01

    The tenth meeting of the Astronomical and Astrophysical Society of America (later to become the AAS), held in August 1909, was also its tenth-anniversary (or decennial) meeting. Fifty-three members were present, as contrasted with the 1400 expected for the 194th, Centennial meeting to be held in Chicago in May-June 1999, and forty-one papers were presented, rather than the 1000 predicted for next year. Other similarities and differences between meetings then and now will be described and illustrated. Simon Newcomb, the first AAS President, had died in July 1909, and Edward C. Pickering, who had succeeded him in 1905 and was to remain President until 1919, eulogized him at the Yerkes meeting. Two Committees, on Luminous Meteors and on Comets, respectively, presented their reports, the latter's dealing mostly with plans for Comet Halley at its 1910 apparition. A high-level Special Committee issued a statement decrying a newspaper furor over establishing communication with Mars, which they said was then ``outside the range of contemporary science." Six of the members present at the 1909 meeting were women. Joel Stebbins, later to be Councilor, Secretary, Vice President and President, presented his first AAS paper, on his new selenium (photo-resistive) photometry. Frank Schlesinger, another future Society President, was also present and read an instrument-design paper. Ten of the papers were given by Yerkes and University of Chicago astronomers, including three by E. E. Barnard and two by Kurt Laves. Another six papers from distant Lick Observatory members were read in absentia. S. W. Burnham, who was at the Yerkes meeting, was the one famous astronomer who never joined the Society. Finally, the Council authorized publication of a Decennial Book, to provide a record of the first ten years of the young Society.

  17. Effects of the bacterial algicide IRI-160AA on cellular morphology of harmful dinoflagellates.

    PubMed

    Pokrzywinski, Kaytee L; Tilney, Charles L; Modla, Shannon; Caplan, Jeffery L; Ross, Jean; Warner, Mark E; Coyne, Kathryn J

    2017-02-01

    The algicide, IRI-160AA, induces mortality in dinoflagellates but not other species of algae, suggesting that a shared characteristic or feature renders this class of phytoplankton vulnerable to the algicide. In contrast to other eukaryotic species, the genome of dinoflagellates is stabilized by high concentrations of divalent cations and transition metals and contains large amounts of DNA with unusual base modifications. These distinctions set dinoflagellates apart from other phytoplankton and suggest that the nucleus may be a dinoflagellate-specific target for IRI-160AA. In this study, morphological and ultrastructural changes in three dinoflagellate species, Prorocentrum minimum, Karlodinium veneficum and Gyrodinium instriatum, were evaluated after short-term exposure to IRI-160AA using super resolution structured illumination microscopy (SR-SIM) and transmission electron microscopy (TEM). Exposure to the algicide resulted in cytoplasmic membrane blebbing, differing chloroplast morphologies, nuclear expansion, and chromosome expulsion and/or destabilization. TEM analysis showed that chromosomes of algicide-treated K. veneficum appeared electron dense with fibrous protrusions. In algicide-treated P. minimum and G. instriatum, chromosome decompaction occurred, while for P. minimum, nuclear expulsion was also observed for several cells. Results of this investigation demonstrate that exposure to the algicide destabilizes dinoflagellate chromosomes, although it was not clear if the nucleus was the primary target of the algicide or if the observed effects on chromosomal structure were due to downstream impacts. In all cases, changes in cellular morphology and ultrastructure were observed within two hours, suggesting that the algicide may be an effective and rapid approach to mitigate dinoflagellate blooms.

  18. Heavy quarkonium production: Nontrivial transition from pA to AA collisions

    SciTech Connect

    Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Ivan; Pirner, H. J.

    2011-01-15

    Two novel QCD effects, double-color filtering and mutual boosting of the saturation scales in colliding nuclei, affect the transparency of the nuclei for quark dipoles in comparison with proton-nucleus collisions. The former effect increases the survival probability of the dipoles, since color filtering in one nucleus makes the other one more transparent. The second effect acts in the opposite direction and is stronger; it makes the colliding nuclei more opaque than in the case of pA collisions. As a result of parton saturation in nuclei the effective scale is shifted upward, which leads to an increase of the gluon density at small x. This in turn leads to a stronger transverse momentum broadening in AA compared with pA collisions, i.e., to an additional growth of the saturation momentum. Such a mutual boosting leads to a system of reciprocity equations, which result in a saturation scale, a few times higher in AA than in pA collisions at the energies of the large hadron collider (LHC). Since the dipole cross section is proportional to the saturation momentum squared, the nuclei become much more opaque for dipoles in AA than in pA collisions. For the same reason gluon shadowing turns out to be boosted to a larger magnitude compared with the product of the gluon shadowing factors in each of the colliding nuclei. All these effects make it more difficult to establish a baseline for anomalous J/{Psi} suppression in heavy ion collisions at high energies.

  19. The strain path dependence of plastic deformation response of AA5754: Experiment and modeling

    SciTech Connect

    Pham, Minh-Son; Hu, Lin; Iadicola, Mark; Creuziger, Adam; Rollett, Anthony D.

    2013-12-16

    This work presents modeling of experiments on a balanced biaxial (BB) pre-strained AA5754 alloy, subsequently reloaded uniaxially along the rolling direction and transverse direction. The material exhibits a complex plastic deformation response during the change in strain path due to 1) crystallographic texture, 2) aging (interactions between dislocations and Mg atoms) and 3) recovery (annihilation and re-arrangement of dislocations). With a BB prestrain of about 5 %, the aging process is dominant, and the yield strength for uniaxially deformed samples is observed to be higher than the flow stress during BB straining. The strain hardening rate after changing path is, however, lower than that for pre-straining. Higher degrees of pre-straining make the dynamic recovery more active. The dynamic recovery at higher strain levels compensates for the aging effect, and results in: 1) a reduction of the yield strength, and 2) an increase in the hardening rate of re-strained specimens along other directions. The yield strength of deformed samples is further reduced if these samples are left at room temperature to let static recovery occur. The synergistic influences of texture condition, aging and recovery processes on the material response make the modeling of strain path dependence of mechanical behavior of AA5754 challenging. In this study, the influence of crystallographic texture is taken into account by incorporating the latent hardening into a visco-plastic self-consistent model. Different strengths of dislocation glide interaction models in 24 slip systems are used to represent the latent hardening. Moreover, the aging and recovery effects are also included into the latent hardening model by considering strong interactions between dislocations and dissolved atom Mg and the microstructural evolution. These microstructural considerations provide a powerful capability to successfully describe the strain path dependence of plastic deformation behavior of AA5754.

  20. Inhibiting CD146 by its Monoclonal Antibody AA98 Improves Radiosensitivity of Cervical Cancer Cells

    PubMed Central

    Cheng, Huawen

    2016-01-01

    Background Cervical cancer is one of the major causes of cancer death of females worldwide. Radiotherapy is considered effective for cervical cancer treatment, but the low radiosensitivity found in some cases severely affects therapeutic outcomes. This study aimed to reveal the role of CD146, an important adhesion molecule facilitating tumor angiogenesis, in regulating radiosensitivity of cervical cancer cells. Material/Methods CD146 protein expression was compared in normal cells, cervical cancer cells with lower radiosensitivity, and cervical cancer cells with higher sensitivity from cervical squamous cell carcinoma patients. Anti-CD146 monoclonal antibody AA98 was used to inhibit CD146 in human cervical cancer SiHa cells with relatively low radiosensitivity, and then the cell survival and apoptosis changes after radiation were detected by colony formation assay and flow cytometry. Results CD146 protein was significantly up-regulated in cervical cancer cells (P<0.001), especially in cancer cells with lower radiosensitivity. The SiHa cells treated with AA98 showed more obvious inhibition in cell survival (P<0.05) and promotion in cell apoptosis (P<0.01) after radiation, compared to the untreated cells. More dramatic changes in apoptotic factors Caspase 3 and Bcl-XL were also detected in AA98-treated cells. Conclusions These results indicate that inhibiting CD146 improves the effect of radiation in suppressing SiHa cells. This study shows the potential of CD146 as a target for increasing radiosensitivity of cervical cancer cells, which might allow improvement in treatment outcome in cervical cancer. Further studies are necessary for understanding the detailed mechanism of CD146 in regulating radiosensitivity. PMID:27647179

  1. Stability of DNA duplexes containing GG, CC, AA, and TT mismatches.

    PubMed

    Tikhomirova, Anna; Beletskaya, Irina V; Chalikian, Tigran V

    2006-09-05

    We employed salt-dependent differential scanning calorimetric measurements to characterize the stability of six oligomeric DNA duplexes (5'-GCCGGAXTGCCGG-3'/5'-CCGGCAYTCCGGC-3') that contain in the central XY position the GC, AT, GG, CC, AA, or TT base pair. The heat-induced helix-to-coil transitions of all the duplexes are associated with positive changes in heat capacity, DeltaC(p), ranging from 0.43 to 0.53 kcal/mol. Positive values of DeltaC(p) result in strong temperature dependences of changes in enthalpy, DeltaH degrees, and entropy, DeltaS degrees , accompanying duplex melting and cause melting free energies, DeltaG degrees, to exhibit characteristically curved shapes. These observations suggest that DeltaC(p) needs to be carefully taken into account when the parameters of duplex stability are extrapolated to temperatures distant from the transition temperature, T(M). Comparison of the calorimetric and van't Hoff enthalpies revealed that none of the duplexes studied in this work exhibits two-state melting. Within the context of the central AXT/TYA triplet, the thermal and thermodynamic stabilities of the duplexes in question change in the following order: GC > AT > GG > AA approximately TT > CC. Our estimates revealed that the thermodynamic impact of the GG, AA, and TT mismatches is confined within the central triplet. In contrast, the thermodynamic impact of the CC mismatch propagates into the adjacent helix domains and may involve 7-9 bp. We discuss implications of our results for understanding the origins of initial recognition of mismatched DNA sites by enzymes of the DNA repair machinery.

  2. Developing an Empirical Relationship to Predict Tensile Strength of Friction Stir Welded AA2219 Aluminum Alloy

    NASA Astrophysics Data System (ADS)

    Elangovan, K.; Balasubramanian, V.; Babu, S.

    2008-12-01

    AA2219 aluminum alloy (Al-Cu-Mn alloy) has gathered wide acceptance in the fabrication of lightweight structures requiring a high strength-to-weight ratio and good corrosion resistance. Friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a nonconsumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force, etc., and tool pin profile play a major role in deciding the joint strength. An attempt has been made to develop an empirical relationship between FSW variables to predict tensile strength of the friction stir welded AA2219 aluminum alloy. To obtain the desired strength, it is essential to have a complete control over the relevant process parameters to maximize the tensile strength on which the quality of a weldment is based. Therefore, it is very important to select and control the welding process parameter for obtaining maximum strength. To achieve this various prediction methods such as response surface method (RSM), analysis of variance (ANOVA), Student’s t-test, coefficient of determination, etc., can be applied to define the desired output variables through developing mathematical models to specify the relationship between the output parameters and input variables. Four factors, five levels central composite design have been used to minimize number of experimental conditions. The developed mathematical relationship can be effectively used to predict the tensile strength of FSW joints of AA2219 aluminum alloy at 95% confidence level.

  3. A computational study of low-head direct chill slab casting of aluminum alloy AA2024

    NASA Astrophysics Data System (ADS)

    Hasan, Mainul; Begum, Latifa

    2016-04-01

    The steady state casting of an industrial-sized AA2024 slab has been modeled for a vertical low-head direct chill caster. The previously verified 3-D CFD code is used to investigate the solidification phenomena of the said long-range alloy by varying the pouring temperature, casting speed and the metal-mold contact heat transfer coefficient from 654 to 702 °C, 60-180 mm/min, and 1.0-4.0 kW/(m2 K), respectively. The important predicted results are presented and thoroughly discussed.

  4. Heavy flavor R AA and vn in event-by-event viscous relativistic hydrodynamics

    NASA Astrophysics Data System (ADS)

    Prado, Caio A. G.; Noronha-Hostler, Jacquelyn; Cosentino, Mauro R.; Munhoz, Marcelo G.; Noronha, Jorge; Suaide, Alexandre A. P.

    2017-01-01

    Recently it has been shown that a realistic description of the medium via event-by-event viscous hydrodynamics plays an important role in the long-standing R AA vs. v 2 puzzle at high pT . In this proceedings we begin to extend this approach to the heavy flavor sector by investigating the effects of full event-by-event fluctuating hydrodynamic backgrounds on the nuclear suppression factor and v 2{2} of heavy flavor mesons and non-photonic electrons at intermediate to high pT . We also show results for v 3{2} of B 0 and D0 for PbPb collisions at .

  5. Effect of Surface Pretreatment on the Underpaint Corrosion of AA2024-T3 at Various Temperatures

    DTIC Science & Technology

    2006-04-01

    CORROSION SCIENCE SECTION 300 CORROSION—APRIL 2006 Submitted for publication December 2004; in revised form , June 2005. ‡ Corresponding author. E...induce acid pitting and alkaline attack, are often formed by Cu- and Fe-containing intermetallics or replated Cu.1-12 In AA2024-T3 (UNS A92024),(1) pit...these particles and elsewhere.3 The 0010-9312/06/000059/$5.00+$0.50/0 © 2006, NACE International Report Documentation Page Form ApprovedOMB No. 0704

  6. Carbonic anhydrase binding site parameterization in OPLS-AA force field.

    PubMed

    Bernadat, Guillaume; Supuran, Claudiu T; Iorga, Bogdan I

    2013-03-15

    The parameterization of carbonic anhydrase binding site in OPLS-AA force field was performed using quantum chemistry calculations. Both OH2 and OH(-) forms of the binding site were considered, showing important differences in terms of atomic partial charges. Three different parameterization protocols were used, and the results obtained highlighted the importance of including an extended binding site in the charge calculation. The force field parameters were subsequently validated using standard molecular dynamics simulations. The results presented in this work should greatly facilitate the use of molecular dynamics simulations for studying the carbonic anhydrase, and more generally, the metallo-enzymes.

  7. Presence of glycosaminoglycans in purified AA type amyloid fibrils associated with juvenile rheumatoid arthritis.

    PubMed Central

    Magnus, J H; Husby, G; Kolset, S O

    1989-01-01

    Previous studies have strongly suggested an association between glycosaminoglycans and tissue deposits of amyloid. The present study was aimed at studying this association in purified preparations of hepatic amyloid fibrils obtained from human AA type secondary amyloidosis. Glycosaminoglycans were isolated by gradient ion exchange chromatography of purified amyloid fibrils treated with pronase. Degradation with specific enzymes identified the glycosaminoglycans as chondroitin sulphate, dermatan sulphate, and heparin/heparan sulphate. The total amount of glycosaminoglycans specifically coisolated with the amyloid fibrils was 15 micrograms/mg fibril weight. The presence of glycosaminoglycans in amyloid may play a part in the incorporation of structurally diverse protein precursors into amyloid fibrils of identical ultrastructure. PMID:2930277

  8. Numerical and experimental study of Bauschinger effect on AA5182 sheets

    NASA Astrophysics Data System (ADS)

    Talla, Abhinav

    For stamping process, most of the sheet metal elements undergo a complicated deformation process that may comprise a sequence of stretching, bending, unbending and reverse bending processes. For this kind of deformation, the Bauschinger effect must be considered in order to calculate the internal stress within the parts before springback. To understand the Bauschinger effect phenomenon on AA5182-O temper, a fixture for cyclic double-shear test has been designed and manufactured. This test can induce cyclic shear loading on the specimen during experiment. LS-Dyna has also been used to simulate this experiment.

  9. Statistical Analysis of High-Cycle Fatigue Behavior of Friction Stir Welded AA5083-H321

    DTIC Science & Technology

    2011-01-01

    durable structures are: (a) FSW is 111being used in a serial production of aluminum alloy-based 112ferryboat deck structures in Finland; (b) Al-Mg-Si-based...material is circa 160 MPa (i.e., around 40% lower 218than that in the base metal). 219The FSW tool used was made of tool steel , had a 25 mm- 220diameter...the literature revealed that high-cycle fatigue data associated with friction stir-welded ( FSW ) joints of AA5083-H321 (a solid-solution-strengthened

  10. Effect of cooling rate on microstructure of friction-stir welded AA1100 aluminum alloy

    NASA Astrophysics Data System (ADS)

    Yi, D.; Mironov, S.; Sato, Y. S.; Kokawa, H.

    2016-06-01

    In this work, the microstructural changes occurring during cooling of friction-stir welded aluminum alloy AA1100 were evaluated. To this end, friction-stir welding (FSW) was performed in a wide range of cooling rates of 20-62 K/s and the evolved microstructures were studied by using electron backscatter diffraction. Below 0.6 Tm (Tm being the melting point), the stir zone material was found to experience no significant changes during cooling. At higher FSW temperatures, however, notable changes occurred in the welded material, including grain growth, sharpening of texture, reduction of the fraction of high-angle boundaries and material softening.

  11. Lava entering water: the different behaviour of aa and pahoehoe at the Nesjahraun, Thingvellir, Iceland

    NASA Astrophysics Data System (ADS)

    Stevenson, J. A.; Mitchell, N.; Mochrie, F.; Cassidy, M.; Pinkerton, H.

    2009-12-01

    The Nesjahraun is a basaltic lava flow that erupted 1800 years ago from a subaerial fissure extending NE from the Hengill central volcano along the Thingvellir graben. The Nesjahraun entered the lake "Thingvallavatn" on its southern shore and exemplifies lava flowing into water in a relatively sheltered, lacustrine environment. This study combines airborne LiDAR, sidescan sonar, and CHIRP seismic data with field observations to investigate the behaviour of the lava as it entered the water. The early stages of the eruption produced pahoehoe sheet lava that is exposed as stacks of thin, vesicular, flows (5-20 cm thick) resting upon and surrounding low (<5 m) piles of coarse, unconsolidated, variably-oxidised spatter. Clefts, 2-5 m wide, spaced ~50 m apart, and with subhorizontal striations on the walls, extend <50 m inland from the lake. They likely represent channels or collapsed tubes along which lava was delivered into the water. A circular littoral cone, Eldborg, formed when water infiltrated a lava tube. Offshore, the water deepens quickly, suggesting that this part of the flow ends as a steep talus ramp. Later, the flow focussed into an aa channel that split along the shore into individual flow lobes 1-50 m wide. Aa clinker is exposed on the water's edge, as well as glassy sand and gravel containing irregularly-shaped intrusions. The cores of the flow lobes contain coherent, but hackly-fractured lava. Mounds of lapilli-sized scoria and the large double cone of Grámelur were formed in littoral explosions. The aa flow can be identified over 1 km offshore in the CHIRP and sidescan data, the latter suggesting that the flow lobes remained coherent while flowing down a gradient of <10 degrees. The Nesjahraun demonstrates that, even in the absence of ocean waves, littoral explosions are ubiquitous, that pahoehoe flows advance by construction of a talus ramp, and that with a high flux and shallow gradient, it is possible for aa flows to penetrate water and to remain

  12. Lithium AA-Size Cells for Navy Mine Applications. 1. Selection and Test Plan

    DTIC Science & Technology

    1993-11-30

    plan for their evaluation for mine batery &velopment. We wish to thank Mr. Clyde W. Bowers (NSWCMWEA-Code 7000) and Mr. Frank Visk (NSWCDDWODET-Cce G94...MnO2 cells: Varta Batteries Inc. and Dowty Batteries. There are notable differences in design and performance. Varta claims cell type CR AA has 2.0 Ah...cells. The cell is designed for good low-rate performance. The Dowty cell type LIM 145H is a spirally wound cell design with a vent. This cell provides a

  13. Laboratory study on the behaviour of spent AA household alkaline batteries in incineration.

    PubMed

    Almeida, Manuel F; Xará, Susana M; Delgado, Julanda; Costa, Carlos A

    2009-01-01

    The quantitative evaluation of emissions from incineration is essential when Life Cycle Assessment (LCA) studies consider this process as an end-of-life solution for some wastes. Thus, the objective of this work is to quantify the main gaseous emissions produced when spent AA alkaline batteries are incinerated. With this aim, batteries were kept for 1h at 1273K in a refractory steel tube hold in a horizontal electric furnace with temperature control. At one end of the refractory steel tube, a constant air flow input assures the presence of oxygen in the atmosphere and guides the gaseous emissions to a filter system followed by a set of two bubbler flasks having an aqueous solution of 10% (v/v) nitric acid. After each set of experiments, sulphur, chlorides and metals (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Tl and Zn) were analyzed in both the solutions obtained from the steel tube washing and from the bubblers. Sulphur, chlorides and metals were quantified, respectively, using barium sulfate gravimetry, the Volhard method and atomic absorption spectrometry (AAS). The emissions of zinc, the most emitted metal, represent about 6.5% of the zinc content in the batteries. Emissions of manganese (whose oxide is the main component of the cathode) and iron (from the cathode collector) are negligible when compared with their amount in AA alkaline batteries. Mercury is the metal with higher volatility in the composition of the batteries and was collected even in the second bubbler flask. The amount of chlorides collected corresponds to about 36% of the chlorine in the battery sleeve that is made from PVC. A considerable part of the HCl formed in PVC plastic sleeve incineration is neutralized with KOH, zinc and manganese oxides and, thus, it is not totally released in the gas. Some of the emissions are predictable through a thermodynamic data analysis at temperatures in the range of 1200-1300K taking into account the composition of the batteries. This analysis was done

  14. Laboratory study on the behaviour of spent AA household alkaline batteries in incineration

    SciTech Connect

    Almeida, Manuel F. Xara, Susana M.; Delgado, Julanda; Costa, Carlos A.

    2009-01-15

    The quantitative evaluation of emissions from incineration is essential when Life Cycle Assessment (LCA) studies consider this process as an end-of-life solution for some wastes. Thus, the objective of this work is to quantify the main gaseous emissions produced when spent AA alkaline batteries are incinerated. With this aim, batteries were kept for 1 h at 1273 K in a refractory steel tube hold in a horizontal electric furnace with temperature control. At one end of the refractory steel tube, a constant air flow input assures the presence of oxygen in the atmosphere and guides the gaseous emissions to a filter system followed by a set of two bubbler flasks having an aqueous solution of 10% (v/v) nitric acid. After each set of experiments, sulphur, chlorides and metals (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Tl and Zn) were analyzed in both the solutions obtained from the steel tube washing and from the bubblers. Sulphur, chlorides and metals were quantified, respectively, using barium sulfate gravimetry, the Volhard method and atomic absorption spectrometry (AAS). The emissions of zinc, the most emitted metal, represent about 6.5% of the zinc content in the batteries. Emissions of manganese (whose oxide is the main component of the cathode) and iron (from the cathode collector) are negligible when compared with their amount in AA alkaline batteries. Mercury is the metal with higher volatility in the composition of the batteries and was collected even in the second bubbler flask. The amount of chlorides collected corresponds to about 36% of the chlorine in the battery sleeve that is made from PVC. A considerable part of the HCl formed in PVC plastic sleeve incineration is neutralized with KOH, zinc and manganese oxides and, thus, it is not totally released in the gas. Some of the emissions are predictable through a thermodynamic data analysis at temperatures in the range of 1200-1300 K taking into account the composition of the batteries. This analysis was done

  15. Symbiotic seed germination and protocorm development of Aa achalensis Schltr., a terrestrial orchid endemic from Argentina.

    PubMed

    Sebastián, Fracchia; Vanesa, Silvani; Eduardo, Flachsland; Graciela, Terada; Silvana, Sede

    2014-01-01

    Aa achalensis is an endangered terrestrial orchid endemic from Argentina. In vitro symbiotic seed germination was evaluated for its propagation. Five different fungal strains were isolated from this species: two Rhizoctonia-like related to Thanatephorus cucumeris and three ascomicetaceous fungi belonging to Phialophora graminicola and one to an uncultured Pezizaceae. All five isolates promoted seed germination being one T. cucumeris strain the most effective. After 16 weeks of growth, 30% of A. achalensis protocorms developed until seedlings with two/four leaves in this treatment. These findings open an opportunity to the knowledge and preservation of this species.

  16. Active Moss Biomonitoring of Atmospheric Trace Element Deposition in Belgrade Urban Area using ENAA and AAS

    SciTech Connect

    Anicic, M.; Tasic, M.; Tomasevic, M.; Rajsic, S.; Frontasyeva, M. V.; Strelkova, L. P.; Steinnes, E.

    2007-11-26

    Active biomonitoring of air quality in Belgrade, Serbia, was performed using the moss Sphagnum girgensohnii. Moss bags were exposed in parallel with and without irrigation respectively for four consecutive 3-month periods at three urban sites. Twenty-nine elements were determined in the exposed moss samples by ENAA and three (Cu, Cd, and Pb) by AAS. The relative accumulation factor (RAF) was greater than 1 for the majority of elements. Elements such as Cl, K, Rb and Cs, however, leached from the moss tissue during the exposure time. For all exposure periods, higher uptake in the irrigated moss bags was evident for Al, Cr, Fe, Cu, Zn, Sr, Pb, and Cd.

  17. Holographic transmission gratings stored with high spatial frequency in PVA/AA photopolymers

    NASA Astrophysics Data System (ADS)

    Fernández, E.; Fuentes, R.; Ortuño, M.; Beléndez, A.; Pascual, I.

    2014-05-01

    High spatial frequencies in holographic gratings are difficult to obtain by limitations of the recording material. In this work, the results obtained after storing holographic transmission gratings with a spatial frequency of 2656 lines/mm in a material based on PVA/AA are presented. A chain transfer agent, the 4,4 '-azobis (4-cyanopentanoic acid) (ACPA) has been incorporated in the material composition to improve the spatial resolution. The concentration of the ACPA in the different compositions of the material has been modified in order to find the optimal concentration which gets obtain the maximum diffraction efficiency for high spatial frequencies.

  18. Improving the performance of PVA/AA photopolymers for holographic recording

    NASA Astrophysics Data System (ADS)

    Ortuño, Manuel; Fernández, Elena; Fuentes, Rosa; Gallego, Sergi; Pascual, Inmaculada; Beléndez, Augusto

    2013-01-01

    Photopolymers have proven to be useful recording material for applications such as holographic data storage or holographic optical elements. In this work, the performance of a 900 μm thick polyvinyl alcohol/acrylamide photopolymer (PVA/AA) developed in our laboratory is improved by means of 4,4' azo-bis-(4-cyanopentanoic acid), ACPA. We minimizing the initiator effect of ACPA working at low recording intensity of 5 mW/cm2. The improved photopolymer presents low scattering and diffraction efficiencies as high as 85%. This result is related to the chain transfer effect produced by ACPA. .

  19. A homology model of SERT based on the LeuT(Aa) template.

    PubMed

    Ravna, Aina Westrheim; Jaronczyk, Malgorzata; Sylte, Ingebrigt

    2006-11-01

    A human serotonin transporter (SERT) model has been constructed based on the crystal structure of the bacterial homologue of Na(+)/Cl(-)-dependent neurotransmitter transporters from Aquifex aeolicus (LeuT(Aa)). Amino acids in the ligand binding area predicted by ICM pocket finder included Tyr95, Ala96, Asp98, Gly100 (transmembrane helix (TMH) 1), Ala169, Ile172, Ala173, Tyr176 (TMH3), Phe335, Ser336, Gly338, Phe341, Val343 (TMH6), Thr439, Ala441, and Gly442 (TMH8). The present model is an updated working tool for experimental studies on SERT.

  20. Cyanide-induced cytochrome a,a3 oxidation-reduction responses in rat brain in vivo.

    PubMed Central

    Piantadosi, C A; Sylvia, A L; Jöbsis, F F

    1983-01-01

    The sensitivity of the brain to cyanide-induced histotoxic hypoxia and the protective effects of known cyanide antagonists, have been assessed in vivo by reflectance spectrophotometry. Cyanide-related changes in cytochrome a,a3 (cytochrome c oxidase) oxidation-reduction (redox) state, tissue hemoglobin saturation, and local blood volume were continuously monitored in cerebral cortex of rats. Noncumulative, dose-dependent inhibition of the in situ mitochondrial respiratory chain was evaluated directly by measuring increases in reduction levels of the terminal oxidase. These transient cytochrome a,a3 reductions were accompanied by increases in regional cerebral hemoglobin saturation and blood volume. Cytochrome redox responses were not altered either in magnitude or kinetics by hyperoxia; however, the cyanide-cytochrome dose-response curve was greatly shifted to the right by pretreatment with sodium nitrite, and the recovery rate of cytochrome a,a3 from cyanide-induced reduction was enhanced fourfold by pretreatment with sodium thiosulfate. PMID:6313756

  1. Transgenic cotton expressing synthesized scorpion insect toxin AaHIT gene confers enhanced resistance to cotton bollworm (Heliothis armigera) larvae.

    PubMed

    Wu, Jiahe; Luo, Xiaoli; Wang, Zhian; Tian, Yingchuan; Liang, Aihua; Sun, Yi

    2008-03-01

    A synthetic scorpion Hector Insect Toxin (AaHIT) gene, under the control of a CaMV35S promoter, was cloned into cotton via Agrobacterium tumefaciens-mediated transformation. Southern blot analyses indicated that integration of the transgene varied from one to more than three estimated copies per genome; seven homozygous transgenic lines with one copy of the T-DNA insert were then selected by PCR and Southern blot analysis. AaHIT expression was from 0.02 to 0.43% of total soluble protein determined by western blot. These homozygous transgenic lines killed larvae of cotton bollworm (Heliothis armigera) by 44-98%. The AaHIT gene could used therefore an alternative to Bt toxin and proteinase inhibitor genes for producing transgenic cotton crops with effective control of bollworm.

  2. Superior signal-to-noise ratio of a new AA1 sequence for random-modulation continuous-wave lidar.

    PubMed

    Rybaltowski, Adam; Taflove, Allen

    2004-08-01

    In an earlier work [Proc. SPIE 4484, 216 (2001)] we proposed a new AA1 modulation sequence for random-modulation continuous-wave lidar. It possesses significantly better signal properties than other pseudorandom codes (the M, A1, and A2 sequences). We derive and compare the signal-to-noise ratio (SNR) of the new AA1 sequence with those of previous modulation sequences. Using a figure of merit proposed for pseudorandom sequences in additive (and generally colored) noise, we show that the SNR of the AA1 sequence in 1/f noise can be as much as 50 times better than that of the commonly used M sequence. This improved SNR should permit as much as a 7:1 increase of the maximum lidar sensing range in baseband-modulation direct-detection infrared lidar with no significant changes to the transmitter and receiver.

  3. Influences of post-weld heat treatment on tensile properties of friction stir-welded AA6061 aluminum alloy joints

    SciTech Connect

    Elangovan, K.; Balasubramanian, V.

    2008-09-15

    This paper reports on studies of the influences of various post-weld heat treatment procedures on tensile properties of friction stir-welded AA6061 aluminum alloy joints. Rolled plates of 6-mm thick AA6061 aluminum alloy were used to fabricate the joints. Solution treatment, an artificial aging treatment and a combination of both were given to the welded joints. Tensile properties such as yield strength, tensile strength, elongation and joint efficiency were evaluated. Microstructures of the welded joints were analyzed using optical microscopy and transmission electron microscopy. A simple artificial aging treatment was found to be more beneficial than other treatment methods to enhance the tensile properties of the friction stir-welded AA6061 aluminum alloy joints.

  4. Preparation of thin film nanofibrous composite NF membrane based on EDC/NHS modified PAN-AA nanofibrous substrate

    NASA Astrophysics Data System (ADS)

    Yang, Y.; Wang, X.; Hsiao, B. S.

    2016-07-01

    A novel kind of thin-film nanofibrous composite (TFNC) nanofiltration (NF) membranes consisting of a polyamide (PA) barrier layer were successfully fabricated by interfacial polymerization (IFP) based on electrospun double-layer nanofibrous substrates, which have an ultrathin poly (acrylonitrile-co-acrylic acid) (PAN-AA) nanofibrous layer as top layer and a thicker polyacrylonitrile (PAN) nanofiber layer as bottom porous support layer. Immersing PAN/PAN-AA nanofibrous substrates into 1-ethyl-(3-3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) aqueous solution and piperazine (PIP) aqueous solution (0.20 wt%) sequentially for a period of time, the carboxyl groups on PAN-AA nanofibers were activated by carbodiimide and then reacted with the amide groups. The as prepared composite membrane has an integrated structure with high rejection rate (98.0%); high permeate flux (40.4 L/m2h) for MgSO4 aqueous solution (2 g/L).

  5. Stability of 100 homo and heterotypic coiled-coil a-a' pairs for ten amino acids (A, L, I, V, N, K, S, T, E, and R).

    PubMed

    Acharya, Asha; Rishi, Vikas; Vinson, Charles

    2006-09-26

    We present the thermal stability monitored by circular dichroism (CD) spectroscopy at 222 nm of 100 heterodimers that contain all possible coiled-coil a-a' pairs for 10 amino acids (I, V, L, N, A, K S, T, E, and R). This includes the stability of 36 heterodimers for 6 amino acids (I, V, L, N, A, and K) previously described and 64 new heterodimers including the 4 amino acids (S, T, E, and R). We have calculated a double mutant alanine thermodynamic cycle to determine a-a' pair coupling energies to evaluate which a-a' pairs encourage specific dimerization partners. The four new homotypic a-a' pairs (T-T, S-S, R-R, E-E) are repulsive relative to A-A and have destabilizing coupling energies. Among the 90 heterotypic a-a' pairs, the stabilizing coupling energies contain lysine or arginine paired with either an aliphatic or a polar amino acid. The range in coupling energies for each amino acid reveals its potential to regulate dimerization specificity. The a-a' pairs containing isoleucine and asparagine have the greatest range in coupling energies and thus contribute dramatically to dimerization specificity, which is to encourage homodimerization. In contrast, the a-a' pairs containing charged amino acids (K, R, and E) show the least range in coupling energies and promiscuously encourage heterodimerization.

  6. 40 CFR 174.501 - Bacillus thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Vip3Aa protein... REQUIREMENTS FOR PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.501 Bacillus... Bacillus thuringiensis Vip3Aa proteins in or on corn or cotton are exempt from the requirement of...

  7. 40 CFR 174.501 - Bacillus thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... in corn and cotton; exemption from the requirement of a tolerance. 174.501 Section 174.501 Protection... thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Vip3Aa proteins in or on corn or cotton are exempt from the requirement of...

  8. 40 CFR 174.501 - Bacillus thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in corn and cotton; exemption from the requirement of a tolerance. 174.501 Section 174.501 Protection... thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Vip3Aa proteins in or on corn or cotton are exempt from the requirement of...

  9. 40 CFR 174.501 - Bacillus thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... in corn and cotton; exemption from the requirement of a tolerance. 174.501 Section 174.501 Protection... thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Vip3Aa proteins in or on corn or cotton are exempt from the requirement of...

  10. 40 CFR 174.501 - Bacillus thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... in corn and cotton; exemption from the requirement of a tolerance. 174.501 Section 174.501 Protection... thuringiensis Vip3Aa protein in corn and cotton; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Vip3Aa proteins in or on corn or cotton are exempt from the requirement of...

  11. Effects of long-term AA attendance and spirituality on the course of depressive symptoms in individuals with alcohol use disorder.

    PubMed

    Wilcox, Claire E; Pearson, Matthew R; Tonigan, J Scott

    2015-06-01

    Alcohol use disorder (AUD) is associated with depression. Although attendance at Alcoholics Anonymous (AA) meetings predicts reductions in drinking, results have been mixed about the salutary effects of AA on reducing depressive symptoms. In this single-group study, early AA affiliates (n = 253) were recruited, consented, and assessed at baseline, 3, 6, 9, 12, 18, and 24 months. Lagged growth models were used to investigate the predictive effect of AA attendance on depression, controlling for concurrent drinking and treatment attendance. Depression was measured using the Beck Depression Inventory (BDI) and was administered at baseline 3, 6, 12, 18, and 24 months. Additional predictors of depression tested included spiritual gains (Religious Background and Behavior questionnaire [RBB]) and completion of 12-step work (Alcoholics Anonymous Inventory [AAI]). Eighty-five percent of the original sample provided follow-up data at 24 months. Overall, depression decreased over the 24 month follow-up period. AA attendance predicted later reductions in depression (slope = -3.40, p = .01) even after controlling for concurrent drinking and formal treatment attendance. Finally, increased spiritual gains (RBB) also predicted later reductions in depression (slope = -0.10, p = .02) after controlling for concurrent drinking, treatment, and AA attendance. In summary, reductions in alcohol consumption partially explained decreases in depression in this sample of early AA affiliates, and other factors such as AA attendance and increased spiritual practices also accounted for reductions in depression beyond that explained by drinking. (PsycINFO Database Record

  12. Effects of Long-Term AA Attendance and Spirituality on the Course of Depressive Symptoms in Individuals with Alcohol Use Disorder

    PubMed Central

    Wilcox, Claire E.; Pearson, Matthew R.; Tonigan, J. Scott

    2016-01-01

    Alcohol use disorder (AUD) is associated with depression. Although attendance at Alcoholics Anonymous (AA) meetings predicts reductions in drinking, results have been mixed about the salutary effects of AA on reducing depressive symptoms. In this single-group study, early AA affiliates (n=253) were recruited, consented, and assessed at baseline, 3, 6, 9, 12, 18 and 24 months. Lagged growth models were used to investigate the predictive effect of AA attendance on depression, controlling for concurrent drinking and treatment attendance. Depression was measured using the Beck Depression Inventory (BDI) and was administered at baseline 3, 6, 12, 18 and 24 months. Additional predictors of depression tested included spiritual gains, [Religious Background and Behavior questionnaire (RBB)] and completion of 12-step work [(Alcoholics Anonymous Inventory (AAI)]. Eighty-five percent of the original sample provided follow-up data at 24 months. Overall, depression decreased over the 24 month follow-up period. AA attendance predicted later reductions in depression (slope=−3.40, p= 0.01) even after controlling for concurrent drinking and formal treatment attendance. Finally, increased spiritual gains (RBB) also predicted later reductions in depression (slope=−0.10, p=0.02) after controlling for concurrent drinking, treatment, and AA attendance. In sum, reductions in alcohol consumption partially explained decreases in depression in this sample of early AA affiliates, and other factors such as AA attendance and increased spiritual practices also accounted for reductions in depression beyond that explained by drinking. PMID:26076099

  13. Recombinant adeno-associated virus expressing a p53-derived apoptotic peptide (37AA) inhibits HCC cells growth in vitro and in vivo.

    PubMed

    Zhang, Hongyong; Wang, Yufeng; Bai, Yanxia; Shao, Yuan; Bai, Jigang; Ma, Zhenhua; Liu, Qingguang; Wu, Shengli

    2017-02-06

    Recent studies have confirmed that a p53-derived apoptotic peptide (37AA) could act as a tumor suppressor inducing apoptosis in multiple tumor cells through derepressing p73. However, the tumor suppressive effects of recombinant adeno-associated virus (rAAV) expressing 37AA on HCC cells are still unknown. In this study, we successfully constructed a recombinant rAAV expressing 37AA. In vitro and in vivo assays showed that transfection of NT4-37AA/rAAV in HCC cells strongly suppressed cell proliferation, induced apoptosis, and up-regulated the cellular expression of p73. NT4-37AA/rAAV transfection markedly slowed Huh-7 xenografted tumor growth in murine. Pretreatment of HCC cells with p73 siRNA abrogated these effects of NT4-37AA/rAAV. Furthermore, we found that expression of p73 was upregulated and the formation of P73/iASSP complex was prevented when 37AA was introduced into HCC cells. Taken together, these results indicate that introduction of 37AA into HCC cells with a rAAV vector may lead to the development of broadly applicable agents for the treatment of HCC, and the mechanism may, at least in part, be associated with the upregulation of p73 expression and reduced level of P73/iASSP complex.

  14. Who Are the Students Who May Qualify for an Alternate Assessment Based on Modified Academic Achievement Standards (AA-MAS)?: Focus Group Results. Synthesis Report 79

    ERIC Educational Resources Information Center

    Berndt, Sandra; Ebben, Barbara; Kubinski, Eva; Sim, Grant; Liu, Kristin; Lazarus, Sheryl; Thurlow, Martha; Christian, Elizabeth

    2011-01-01

    Beginning in 2007, federal regulations to two major education laws gave state departments of education the option to develop an alternate assessment based on modified achievement standards (AA-MAS) for some students with disabilities. The regulations stated that the AA-MAS was intended for students who were being instructed in the grade-level…

  15. High affinity 3H-Phe uptake by brush border membrane vesicles from whole larvae of Aedes aegypti (AaBMVw)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brush border membrane vesicles from whole Aedes aegypti larvae (AaBBMVw) are confirmed to be valid preparations for membrane transport studies. The Abdul-Rauf and Ellar method was used to isolate AaBBMVw that were frozen, stored for several months, transported to a distant site, thawed and used to s...

  16. Plasma BDNF and PDGF-AA levels are associated with high TCD velocity and stroke in children with sickle cell anemia.

    PubMed

    Hyacinth, Hyacinth I; Gee, Beatrice E; Adamkiewicz, Thomas V; Adams, Robert J; Kutlar, Abdullah; Stiles, Jonathan K; Hibbert, Jacqueline M

    2012-10-01

    Sickle cell anemia (SCA) associated cerebrovascular disease includes vascular remodeling, abnormal cerebral blood flow (CBF) and infarction. We studied the relationships between plasma brain derived neurotropic factor (BDNF), platelet derived growth factors (PDGF-AA and -AB/BB) and high trans-cranial Doppler (TCD) velocity, an indication of CBF velocity. Baseline plasma samples from 39 children (19 SCA with abnormal/high TCD [SATCD], 13 SCA with normal TCD [SNTCD] and 7 healthy non-SCA), were assayed for BDNF, PDGF-AA and -AB/BB plus 11 other cytokines. The sensitivity, specificity and usefulness of these biomarkers for stroke prediction was investigated. All subject groups were of similar age and gender distribution. Mean BDNF was significantly higher among SATCD than SNTCD (p=0.004) as was mean PDGF-AA (p=0.001). Similarly, mean PDGF-AA was higher among SCA subjects who developed stroke than those who did not (p=0.012). Elevated BDNF and PDGF-AA were good predictors of the presence of abnormally high CBF velocity and were both associated with severity of anemia. Elevated PDGF-AA predicted risk for stroke development. Stroke incidence and high TCD velocity were associated with elevated BDNF and PDGF-AA. These findings suggest a role for BDNF and PDGF-AA in the patho-physiological mechanism of cerebrovascular disease in SCA.

  17. Novel Hepatitis B Virus Genotype A Subtyping Assay That Distinguishes Subtype Aa from Ae and Its Application in Epidemiological Studies

    PubMed Central

    Hasegawa, Izumi; Tanaka, Yasuhito; Kramvis, Anna; Kato, Takanobu; Sugauchi, Fuminaka; Acharya, Subrat K.; Orito, Etsuro; Ueda, Ryuzo; Kew, Michael C.; Mizokami, Masashi

    2004-01-01

    The eight genotypes of hepatitis B virus (HBV) have different geographical distributions, virological characteristics, and clinical manifestations. A unique subtype of HBV genotype A (HBV/A) was reported in sub-Saharan Africa, raising the possibility that patients infected with this subtype (HBV/Aa [“a” for African and Asian]) may have different clinical outcomes than other HBV/A isolates (HBV/Ae [“e” for European]). Comparison between 30 HBV/Aa and 30 HBV/Ae isolates indicated that almost all HBV/Ae isolates had G at nucleotide (nt) 1809 and C at nt 1812, whereas HBV/Aa isolates had T1809/T1812. Taking advantage of these two single nucleotide polymorphisms (SNPs), a novel subtype-specific PCR assay in the X/precore/core region was developed. This assay was combined with a restriction fragment length polymorphism assay using BglII in a different region (nt 1984 to 1989), which has a SNP distinguishing HBV/Aa from HBV/Ae, resulting in 100% specificity for the combined assay. Application of the subtyping assay using sera from 109 paid donors in the United States indicated significantly different distributions of HBV/A subtypes among races; African-Americans, Caucasians, and Hispanics had HBV/Ae, whereas Asians had mainly HBV/Aa, suggesting that the HBV/Aa isolates may have been imported by recent immigration from Asia. In conclusion, the specificity and sensitivity of the combined subtyping assay were confirmed, and its usefulness was demonstrated in a practical context. PMID:15220432

  18. Kinetics of the multistep rupture of fibrin 'A-a' polymerization interactions measured using atomic force microscopy.

    PubMed

    Averett, Laurel E; Schoenfisch, Mark H; Akhremitchev, Boris B; Gorkun, Oleg V

    2009-11-18

    Fibrin, the structural scaffold of blood clots, spontaneously polymerizes through the formation of 'A-a' knob-hole bonds. When subjected to external force, the dissociation of this bond is accompanied by two to four abrupt changes in molecular dimension observable as rupture events in a force curve. Herein, the configuration, molecular extension, and kinetic parameters of each rupture event are examined. The increases in contour length indicate that the D region of fibrinogen can lengthen by approximately 50% of the length of a fibrin monomer before rupture of the 'A-a' interaction. The dependence of the dissociation rate on applied force was obtained using probability distributions of rupture forces collected at different pull-off velocities. These distributions were fit using a model in which the effects of the shape of the binding potential are used to quantify the kinetic parameters of forced dissociation. We found that the weak initial rupture (i.e., event 1) was not well approximated by these models. The ruptured bonds comprising the strongest ruptures, events 2 and 3, had kinetic parameters similar to those commonly found for the mechanical unfolding of globular proteins. The bonds ruptured in event 4 were well described by these analyses, but were more loosely bound than the bonds in events 2 and 3. We propose that the first event represents the rupture of an unknown interaction parallel to the 'A-a' bond, events 2 and 3 represent unfolding of structures in the D region of fibrinogen, and event 4 is the rupture of the 'A-a' knob-hole bond weakened by prior structural unfolding. Comparison of the activation energy obtained via force spectroscopy measurements with the thermodynamic free energy of 'A-a' bond dissociation indicates that the 'A-a' bond may be more resistant to rupture by applied force than to rupture by thermal dissociation.

  19. Human vascular smooth muscle cells have at least two distinct PDGF receptors and can secrete PDGF-AA

    SciTech Connect

    Hosang, M.; Rouge, M. )

    1989-01-01

    Platelet-derived growth factor (PDGF), a potent mitogen and chemoattractant for smooth muscle cells and fibroblasts in culture, is believed to play an important role in the formation of proliferative lesions of arterio-sclerosis. PDGF appears as three different dimeric isoforms: AA, AB, and BB. These were recently found to bind to two different receptors, the A/B receptor (which binds all three isoforms) and the B receptor (which binds only PDGF-BB). To find out whether these receptors exhibit functional differences, we have monitored the binding and mitogenic activities of PDGF-AA and -BB in human umbilical vein smooth muscle cells (HSMCs), human dermal fibroblasts (HFs), and Swiss mouse 3T3 cells. With each cell type, there was a good correlation between the maximal levels of DNA synthesis achieved by these isoforms and the numbers of the appropriate receptor present on the cell surface: HMSCs, which have at least 32,000 B receptors but only 8,000 A/B receptors, responded well to PDGF-BB but responded poorly to PDGF-AA; whereas Swiss 3T3 cells, which have about equal numbers of B and A/B receptors (70,000 and 90,000, respectively), responded equally well to both isoforms. PDGF-AB was a more efficacious mitogen of HSMCs and HFs than was PDGF-AA and inhibited (125I)-PDGF-BB binding to HSMCs more effectively than PDGF-AA. This indicates that there may exist a third PDGF receptor type to which PDGF-BB and -AB but not PDGF-AA can bind.

  20. A GPI-anchored alkaline phosphatase is a functional midgut receptor of Cry11Aa toxin in Aedes aegypti larvae

    PubMed Central

    Fernandez, Luisa E.; Aimanova, Karlygash G.; Gill, Sarjeet S.; Bravo, Alejandra; Soberón, Mario

    2005-01-01

    A 65 kDa GPI (glycosylphosphatidyl-inositol)-anchored ALP (alkaline phosphatase) was characterized as a functional receptor of the Bacillus thuringiensis subsp. israelensis Cry11Aa toxin in Aedes aegypti midgut cells. Two (a 100 kDa and a 65 kDa) GPI-anchored proteins that bound Cry11Aa toxin were preferentially extracted after treatment of BBMV (brush boder membrane vesicles) from Ae. aegypti midgut epithelia with phospholipase C. The 65 kDa protein was further purified by toxin affinity chromatography. The 65 kDa protein showed ALP activity. The peptide-displaying phages (P1.BBMV and P8.BBMV) that bound to the 65 kDa GPI–ALP (GPI-anchored ALP) and competed with the Cry11Aa toxin to bind to BBMV were isolated by selecting BBMV-binding peptide-phages by biopanning. GPI–ALP was shown to be preferentially distributed in Ae. aegypti in the posterior part of the midgut and in the caeca, by using P1.BBMV binding to fixed midgut tissue sections to determine the location of GPI–ALP. Cry11Aa binds to the same regions of the midgut and competed with P1.BBMV and P8.BBMV to bind to BBMV. The importance of this interaction was demonstrated by the in vivo attenuation of Cry11Aa toxicity in the presence of these phages. Our results shows that GPI–ALP is an important receptor molecule involved in Cry11Aa interaction with midgut cells and toxicity to Ae. aegypti larvae. PMID:16255715

  1. Heart disease induced by AAS abuse, using experimental mice/rats models and the role of exercise-induced cardiotoxicity.

    PubMed

    Riezzo, I; De Carlo, D; Neri, M; Nieddu, A; Turillazzi, E; Fineschi, V

    2011-05-01

    The anabolic-androgenic steroids (AAS) are all synthetic derivates of testosterone and are commonly used as sport performance enhancers in athletes. The heart is one of the organs most frequently affected by administration of anabolic steroids. A direct myocardial injury caused by AAS is supposed to determine marked hypertrophy in myocardial cells, extensive regional fibrosis and necrosis. A number of excellent studies, using animal models, were performed to evaluate the cardiac effects of AAS. It is known that exogenous administration induced cardiac hypertrophy in vitro and in vivo, and when combined with exercise, anabolic steroid use has been shown to change exercise-induced physiological cardiac hypertrophy to pathophysiological cardiac hypertrophy. However the molecular mechanisms are still poorly understood. It's described that sudden cardiac death, myocardial infarct; ventricular remodelling and cardiomyopathy do to AAS is related to apoptosis and oxidative stress when associated with exercise. Mechanical stimuli and circulating humoral factors (TNF-α, HSP-70, IL-1β) released by the heart and peripheral organs are responsible. Testosterone and derivates can work through genomic (activation of specific androgen receptor, interaction with coactivators and co-repressors transcription factors, gene regulation) and non-genomic mechanism (membrane-receptor-second messenger cascades). Chronic AAS abuse results in different patterns of pathologic alterations, which depend on type, dose, frequency, and mode of use. The difficulty in interpreting experimental data on animals (mice and rats) lies in the diversity of experiments (the diversity of substances, which show different properties, different mice / rats by sex and age, duration of treatment with AAS, dosages used, type, scope and exercise duration).

  2. An amino acid-based oral rehydration solution (AA-ORS) enhanced intestinal epithelial proliferation in mice exposed to radiation

    PubMed Central

    Yin, Liangjie; Gupta, Reshu; Vaught, Lauren; Grosche, Astrid; Okunieff, Paul; Vidyasagar, Sadasivan

    2016-01-01

    Destruction of clonogenic cells in the crypt following irradiation are thought to cause altered gastrointestinal function. Previously, we found that an amino acid-based oral rehydration solution (AA-ORS) improved gastrointestinal function in irradiated mice. However, the exact mechanisms were unknown. Electrophysiology, immunohistochemistry, qPCR, and Western blot analysis were used to determine that AA-ORS increased proliferation, maturation, and differentiation and improved electrolyte and nutrient absorption in irradiated mice. A single-hit, multi-target crypt survival curve showed a significant increase in crypt progenitors in irradiated mice treated with AA-ORS for six days (8.8 ± 0.4) compared to the saline-treated group (6.1 ± 0.3; P < 0.001) without a change in D0 (4.8 ± 0.1 Gy). The Dq values increased from 8.8 ± 0.4 Gy to 10.5 ± 0.5 Gy with AA-ORS treatment (P < 0.01), indicating an increased radiation tolerance of 1.7 Gy. We also found that AA-ORS treatment (1) increased Lgr5+, without altering Bmi1 positive cells; (2) increased levels of proliferation markers (Ki-67, p-Erk, p-Akt and PCNA); (3) decreased apoptosis markers, such as cleaved caspase-3 and Bcl-2; and (4) increased expression and protein levels of NHE3 and SGLT1 in the brush border membrane. This study shows that AA-ORS increased villus height and improved electrolyte and nutrient absorption. PMID:27876791

  3. The multiplicity of spinal AA-5-HT anti-nociceptive action in a rat model of neuropathic pain.

    PubMed

    Malek, Natalia; Kostrzewa, Magdalena; Makuch, Wioletta; Pajak, Agnieszka; Kucharczyk, Mateusz; Piscitelli, Fabiana; Przewlocka, Barbara; Di Marzo, Vincenzo; Starowicz, Katarzyna

    2016-09-01

    There is considerable evidence to support the role of anandamide (AEA), an endogenous ligand of cannabinoid receptors, in neuropathic pain modulation. AEA also produces effects mediated by other biological targets, of which the transient receptor potential vanilloid type 1 (TRPV1) has been the most investigated. Both, inhibition of AEA breakdown by fatty acid amide hydrolase (FAAH) and blockage of TRPV1 have been shown to produce anti-nociceptive effects. Recent research suggests the usefulness of dual-action compounds, which may afford greater anti-allodynic efficacy. Therefore, in the present study, we examined the effect of N-arachidonoyl-serotonin (AA-5-HT), a blocker of FAAH and TRPV1, in a rat model of neuropathic pain after intrathecal administration. We found that treatment with AA-5-HT increased the pain threshold to mechanical and thermal stimuli, with highest effect at the dose of 500nM, which was most strongly attenuated by AM-630, CB2 antagonist, administration. The single action blockers PF-3845 (1000nM, for FAAH) and I-RTX (1nM, for TRPV1) showed lower efficacy than AA-5-HT. Moreover AA-5-HT (500nM) elevated AEA and palmitoylethanolamide (PEA) levels. Among the possible targets of these mediators, only the mRNA levels of CB2, GPR18 and GPR55, which are believed to be novel cannabinoid receptors, were upregulated in the spinal cord and/or DRG of CCI rats. It was previously reported that AA-5-HT acts in CB1 and TRPV1-dependent manner after systemic administration, but here for the first time we show that AA-5-HT action at the spinal level involves CB2, with potential contributions from GRP18 and/or GPR55 receptors.

  4. Different mechanisms influencing permeation of PDGF-AA and PDGF-BB across the blood-brain barrier.

    PubMed

    Kastin, Abba J; Akerstrom, Victoria; Hackler, Laszlo; Pan, Weihong

    2003-10-01

    Platelet-derived growth factor (PDGF) exerts neurotrophic and neuromodulatory effects on the CNS. To determine the permeability of the blood-brain barrier (BBB) to PDGF, we examined the blood-to-brain influx of radioactively labeled PDGF isoforms (PDGF-AA and PDGF-BB) by multiple-time regression analysis after intravenous (i.v.) injection and by in-situ perfusion, and also determined the physicochemical characteristics which affect their permeation across the BBB, including lipophilicity (measured by octanol:buffer partition coefficient), hydrogen bonding (measured by differences in octanol : buffer and isooctane : buffer partition coefficients), serum protein binding (measured by capillary electrophoresis), and stability of PDGF in blood 10 min after i.v. injection (measured by HPLC). After i.v. bolus injection, neither 125I-PDGF-AA nor 125I-PDGF-BB crossed the BBB, their influx rates being similar to that of the vascular marker 99mTc-albumin. 125I-PDGF-AA degraded significantly faster in blood than 125I-PDGF-BB. PDGF-BB, however, was completely bound to a large protein in serum whereas PDGF-AA showed no binding. Thus, degradation might explain the poor blood-to-brain influx of PDGF-AA, whereas protein binding could explain the poor influx of circulating PDGF-BB. Despite their lack of permeation in the intact mouse, both 125I-PDGF-AA and 125I-PDGF-BB entered the brain by perfusion in blood-free buffer, and the significantly faster rate of 125I-PDGF-AA than 125I-PDGF-BB may be explained by the lower hydrogen bonding potential of 125I-PDGF-AA. Thus, the lack of significant distribution of PDGF from blood to brain is not because of the intrinsic barrier function of the BBB but probably because of degradation and protein binding. Information from these studies could be useful in the design of analogues for delivery of PDGF as a therapeutic agent.

  5. [Organization of scientific-methodological work in Central Military Clinical Hospital named after A.A. Vishnevskiĭ].

    PubMed

    Beliakin, S A; Fokin, Iu N; Kokhan, E P; Frolkin, M N

    2009-09-01

    There was congested a wide experience of organization and management of scientific work in the 3rd CMCH by Vishnevsky A.A. for a term of more than 40 years. This experience is subjected to generalization, analyze for the purpose of determination of it's priority orientations of improvement. Scientific-methods work in hospital is rated as a complex of measures, organisationaly-planed and coordinated by purpose and reinforcement of scientific schools of the 3rd CMCH by Vishnevsky A.A., as a basis of effective delivery of specialized medical aid. The vector of scientific researches is directed, generally, to solving questions of military and field medicine.

  6. Binding of monoclonal antibody AA4 to gangliosides on rat basophilic leukemia cells produces changes similar to those seen with Fc epsilon receptor activation

    PubMed Central

    1992-01-01

    The mAb AA4 binds to novel derivatives of the ganglioside Gd1b on rat basophilic leukemia (RBL-2H3) cells. Some of the gangliosides are located close to the high affinity IgE receptor (Fc epsilon RI), and binding of mAb AA4 inhibits Fc epsilon RI-mediated histamine release. In the present study, mAb AA4 was found to bind exclusively to mast cells in all rat tissues examined. In vitro, within 1 min of mAb AA4 binding, the cells underwent striking morphologic changes. They lost their normal spindle shaped appearance, increased their ruffling, and spread over the surface of the culture dish. These changes were accompanied by a redistribution of the cytoskeletal elements, actin, tubulin, and vimentin, but only the actin was associated with the membrane ruffles. Binding of mAb AA4 also induces a rise in intracellular calcium, stimulates phosphatidyl inositol breakdown, and activates PKC. However, the extent of these changes was less than that observed when the cells were stimulated with antigen or antibody directed against the Fc epsilon RI. None of these changes associated with mAb AA4 binding were seen when the cells were exposed to nonspecific IgG, IgE, or four other anti-cell surface antibodies, nor were the changes induced by binding mAb AA4 at 4 degrees C or in the absence of extracellular calcium. Although mAb AA4 does not stimulate histamine release, it enhances the effect of the calcium ionophore A23187 mediated release. The morphological and biochemical effects produced by mAb AA4 are similar to those seen following activation of the cell through the IgE receptor. Therefore, the surface gangliosides which bind mAb AA4 may function in modulating secretory events. PMID:1370498

  7. The influence of ciprofloxacin on hamster ovarian cancer cell line CHO AA8.

    PubMed

    Kloskowski, Tomasz; Olkowska, Joanna; Nazlica, Aybars; Drewa, Tomasz

    2010-01-01

    Abstract: Ciprofloxacin is a chinolone antibiotic, which is used mainly in the treatment of urinary tract infections but also in pulmonary tract, prostate gland, bone and bone marrow infection. Ciprofloxacin is also known for its anticancer in vitro properties. In this study hamster ovarian cancer line CHO AA8 was used for evaluation of cytotoxic properties of ciprofloxacin against neoplastic cells. For this purpose we used different concentrations of ciprofloxacin range from 10 to 1000 microg/mL. Cell viability was counted using trypan blue assay. Ciprofloxacin induced morphological changes and decreased viability in a concentration and time dependent manner within CHO AA8 cells. In low concentrations cytotoxic effect of ciprofloxacin is weak only after 24 h incubation. In the highest concentration of ciprofloxacin, after 24, 48 and 72 h incubation only a very small number of living cells (not exceeding 1%) was observed. No living cells were observed after 96 h of incubation times and ciprofloxacin concentrations of 800 and 1000 micrpg/mL. These promising results deserved future studies on chinolones and ovarian cancer.

  8. Effect of Temperature on Deformation Behavior of Sintered Porous AA2024 During Semisolid Compression

    NASA Astrophysics Data System (ADS)

    Wu, Min; Liu, Yunzhong; Zeng, Zhaoyubo; Luo, Wenyan

    2017-02-01

    Semisolid processing as a promising manufacturing route has recently gained wide use for dense materials. Nevertheless, very few investigations on porous materials or powders were reported and the effect of temperature on deformation behavior of porous materials or powders remains unclear. Sintered porous AA2024 specimens with initial relative density of 83% were compressed at a semisolid state. The liquid volume fraction of gas-atomized AA2024 powders at a semisolid state was determined by the Thermo-calc prediction, the differential scanning calorimetry (DSC) experiment, and metallographic analysis. The results show that the DSC experiment is the best suitable method in this study. As temperature increases, two opposite effects simultaneously act on the microstructure: More powders of samples after compression are broken up, making grains finer, whereas the surface energy decreases, making grains more spherical and coarser. The relative density increases with the increasing temperature because more powders crush and more liquid flows. Thus, the deformation resistance of sintered porous materials decreases, which makes true stress decrease with the increasing temperature. Therefore, the effect of temperature on deformation behavior of sintered porous materials at a semisolid state is attributed to the liquid fraction, which significantly affects the breakup of solid skeleton or powders and the flowing of liquid.

  9. The AAS Working Group on Accessibility and Disability (WGAD): Year 1 Highlights

    NASA Astrophysics Data System (ADS)

    Aarnio, Alicia; Monkiewicz, Jacqueline; Murphy, Nicholas Arnold; Nordhaus, Jason; Tuttle, Sarah E.

    2017-01-01

    The AAS Working Group on Accessibility and Disability (WGAD) was formed in January of 2016 with the express purpose of seeking equity of opportunity and building inclusive practices for disabled astronomers at all career stages. In our first year, the WGAD has been actively developing resources and the online infrastructure for the dissemination of information and engagement with the astronomy community. Our official WGAD website has gone live, and we have used both the access: astronomy google group and blog to discuss specific issues of disability justice and to raise awareness for less-discussed barriers to access. The WGAD has developed relationships and collaboration with AAS inclusion committees (SGMA, CSMA, CSWA) so our work can recognize and address the intersections of identity astronomers occupy. In this presentation, we summarize our year one activities, focusing on our recently developed set of recommendations for journal accessibility to ensure everyone can engage with journal content and navigate the submission process. We will also discuss ongoing and future endeavors: a best practices guide for accessibility to be available via our website, and a site visit program.

  10. My Most Memorable AAS Meeting-December 1957, Butler University, Indianapolis, Indiana

    NASA Astrophysics Data System (ADS)

    Edmondson, F. K.

    1999-05-01

    My attendance at AAS meetings began with the 46th meeting in September 1931 at the brand new Perkins Observatory. This was the first semester of my junior year at Indiana University. Professor Wilbur Cogshall, my astronomy professor, took me to the meeting, and paid my expenses for dormitory accommodations and meals. Hence, my attendance at AAS meetings covers a span of nearly 68 years. There have been so many "memorable" meetings that it is hard to pick just one. However, the 99th meeting in December 1957 at Butler University in Indianapolis, a joint meeting with the AAAS, is memorable because I was in a wheel chair and using crutches, following an injury to my right knee cap. I was a member of the AAAS Committee to select the "best paper" presented at the meeting to receive the Newcomb Cleveland Prize, and Martin Schwarzschild's first report of results from Project Stratoscope was on the program. I showed up at the Committee meeting in my wheel chair, and nominated Martin's paper for the "best paper" award. The Committee asked a lot of questions and then approved the paper by a unanimous vote. The wheel chair and crutches obviously played a role in convincing the Committee that I had strong feelings about the merits of Martin's paper. Allan Sandage was the Warner Prize Lecturer, and reported on the current status of his revision of the cosmic distance scale. Hubble's 1936 distances needed to be increased by a factor of five to ten.

  11. A Study on Flow Behavior of AA5086 Over a Wide Range of Temperatures

    NASA Astrophysics Data System (ADS)

    Asgharzadeh, A.; Jamshidi Aval, H.; Serajzadeh, S.

    2016-03-01

    Flow stress behavior of AA5086 was determined using tensile testing at different temperatures from room temperature to 500 °C and strain rates varying between 0.002 and 1 s-1. The strain rate sensitivity parameter and occurrence of dynamic strain aging were then investigated in which an Arrhenius-type model was employed to study the serrated flow. Additionally, hot deformation behavior at temperatures higher than 320 °C was evaluated utilizing hyperbolic-sine constitutive equation. Finally, a feed forward artificial neural network model with back propagation learning algorithm was proposed to predict flow stress for all deformation conditions. The results demonstrated that the strain rate sensitivity at temperature range of 25-270 °C was negative due to occurrence of dynamic strain aging leading to significant reduction in fracture strain. The serrated yielding activation energy was found to be 46.1 kJ/mol. It indicated that the migration of Mg-atoms could be the main reason for this phenomenon. The hot deformation activation energy of AA5086 was also calculated about 202.3 kJ/mol while the dynamic recovery was the main softening process. Moreover, the ANN model having two hidden layers was shown to be an efficient structure for determining flow stress of the examined alloy for all temperatures and strain rates.

  12. Parameterization of OPLS-AA force field for the conformational analysis of macrocyclic polyketides.

    PubMed

    Kahn, Kalju; Bruice, Thomas C

    2002-07-30

    The parameters for the OPLS-AA potential energy function have been extended to include some functional groups that are present in macrocyclic polyketides. Existing OPLS-AA torsional parameters for alkanes, alcohols, ethers, hemiacetals, esters, and ketoamides were improved based on MP2/aug-cc-pVTZ and MP2/aug-cc-pVDZ calculations. Nonbonded parameters for the sp(3) carbon and oxygen atoms were refined using Monte Carlo simulations of bulk liquids. The resulting force field predicts conformer energies and torsional barriers of alkanes, alcohols, ethers, and hemiacetals with an overall RMS deviation of 0.40 kcal/mol as compared to reference data. Densities of 19 bulk liquids are predicted with an average error of 1.1%, and heats of vaporization are reproduced within 2.4% of experimental values. The force field was used to perform conformational analysis of smaller analogs of the macrocyclic polyketide drug FK506. Structures that adopted low-energy conformations similar to that of bound FK506 were identified. The results show that a linker of four ketide units constitutes the shortest effector domain that allows binding of the ketide drugs to FKBP proteins. It is proposed that the exact chemical makeup of the effector domain has little influence on the conformational preference of tetraketides.

  13. Development of glycyl radical parameters for the OPLS-AA/L force field.

    PubMed

    Komáromi, István; Owen, Michael C; Murphy, Richard F; Lovas, Sándor

    2008-09-01

    On the basis of quantum chemical calculations C(alpha)-glycyl radical parameters have been developed for the OPLS-AA/L force field. The molecular mechanics hypersurface was fitted to the calculated quantum chemical surface by minimizing their molecular mechanics parameter dependent sum-of-squares deviations. To do this, a computer program in which the molecular mechanics energy derivatives with respect to the parameters were calculated analytically was developed, implementing the general method of Lifson and Warshel (J Chem Phys 1968, 49, 5116) for force field parameter optimization. This program, in principle, can determine the optimal parameter set in one calculation if enough representative value points on the quantum chemical potential energy surface are available and there is no linear dependency between the parameters. Some of the parameters in quantum calculations, including several new torsion types around a bond as well as angle parameters at a new central atom type, are not completely separable. Consequently, some restrictions and/or presumptions were necessary during parameter optimization. The relative OPLS-AA energies reproduced those calculated quantum chemically almost perfectly.

  14. THE 1999aa-LIKE TYPE Ia SUPERNOVA IPTF14BDN IN THE ULTRAVIOLET AND OPTICAL

    SciTech Connect

    Smitka, Michael T.; Brown, Peter J.; Suntzeff, Nicholas B.; Zhang, Jujia; Zhai, Qian; Wang, Xiaofeng; Mo, Jun; Zhang, Tianmeng

    2015-11-01

    We present ultraviolet (UV) and optical photometry and spectra of the 1999aa-like supernova (SN) iPTF14bdn. The UV data were observed using the Swift Ultraviolet/Optical Telescope and constitute the first UV spectral series of a 1999aa-like SN. From the photometry, we measure Δm{sub 15}(B) = 0.84 ± 0.05 mag and blue UV colors at epochs earlier than −5 days. The spectra show that the early-time blue colors are the result of less absorption between 2800−3200 Å than is present in normal SNe Ia. Using model spectra fits of the data at −10 and +10 days, we identify the origin of this spectral feature to be a temperature effect in which doubly ionized iron group elements create an opacity “window.” We determine that the detection of high temperatures and large quantities of iron group elements at early epochs imply the mixing of a high Ni mass into the outer layers of the SN ejecta. We also identify the source of the I-band secondary maximum in iPTF14bdn to be the decay of Fe iii to Fe ii, as is seen in normal SNe Ia.

  15. Biotribological properties of UHMWPE grafted with AA under lubrication as artificial joint.

    PubMed

    Deng, Yaling; Xiong, Dangsheng; Wang, Kun

    2013-09-01

    Osteolysis caused by wear particles from polyethylene in the artificial hip joints is a serious issue. In order to endow the low friction and wear of the bearing surface of ultra-high molecular weight polyethylene (UHMWPE) artificial joint for a longer term, hydrophilic acrylic acid (AA) was grafted on UHMWPE powders with the method of ultraviolet irradiation and then the modified powders were hot pressed. The tribological properties of modified UHMWPE sliding against CoCrMo metallic plate on reciprocating tribometer under calf serum, saline and distilled water lubrication during a long-term friction were investigated. The measurement of Fourier-transform infrared spectroscopy indicates that AA is successfully grafted on the surface of UHMWPE powders by photo-induced graft polymerization. Contact angles of UHMWPE are decreased from 83° to 35° by grafting and the surface wettability is effectively improved. The tensile strength of modified sample decreases. The friction coefficient and wear rate of UHMWPE-g-PAA under calf serum, saline and distilled water lubrication are lower than that of untreated UHMWPE. With the increase of grafting ratio, the wear rate of UHMWPE-g-PAA decreases firstly and then increases. The modified UHMWPE with grafting ratio of 3.5 % has the lowest wear rate, which is just quarter of the untreated UHMWPE. The hydrated PAA polymer brushes enclosed in the UHMWPE bulk material provide continuous lubrication during long term sliding.

  16. Evaluation of the Mechanical Properties of AA 6063 Processed by Severe Plastic Deformation

    NASA Astrophysics Data System (ADS)

    Jafarlou, Davoud Mashhadi; Zalnezhad, Erfan; Hamouda, Abdelmagid Salem; Faraji, Ghader; Mardi, Noor Azizi Bin; Hassan Mohamed, Mohsen Abdelnaeim

    2015-05-01

    In this study, the mechanical properties, including surface hardness, tensile strength, fatigue, and fretting fatigue behavior of AA 6063 processed by equal channel angular pressing as the most efficient severe shear plastic deformation (SPD) technique, were investigated. Following the SPD process, samples were subjected to heat treatment (HT), hard anodizing (HA), and a combination of HT and HA. Rotating-bending fretting fatigue tests were performed to explore the samples' response to the fretting condition. From the experimental fatigue and fretting fatigue tests, it was apparent that the SPD treatment had a positive effect on enhancing the fatigue and fretting fatigue lives of the samples at low and high-cyclic loads compared with the HT technique by 78 and 67 pct, and 131 and 154 pct respectively. The results also indicate that the SPD + HT technique significantly increased the fatigue and fretting fatigue lives of the samples at high and low cycles by 15.56 and 8.33 pct, and 14.4 and 5.1 pct respectively, compared with the SPD method. HA of AA6063 increased the fatigue and fretting fatigue lives of SPD + HT-processed samples at low cycle by 15.5 and 18.4 pct respectively; however, at high cycle, HA had reverse effects, whereby the fatigue and fretting fatigue lives of SPD + HT-processed samples decreased by 16.7 and 30 pct, respectively.

  17. The Fourth Joint Meeting of the AAS and ASP, Victoria, June 1952

    NASA Astrophysics Data System (ADS)

    Garstang, R. H.

    1999-05-01

    This meeting was my most memorable because (1) it was the first AAS meeting to be held in Western Canada, (2) it was my first visit to Canada, (3) it was the occasion of the dedication of the Dominion Astrophysical Observatory 72-inch telescope to the memory of J. S. Plaskett, in the presence of Mrs. Plaskett, (4) there was a special symposium on emission line stars, which included a lecture by Paul Merrill to celebrate his retirement, and C. S. Beals and J. A. Rottenberg as the other main speakers, (5) Robert McMath gave the first Aitken lecture in memory of the famous double star astronomer, (6) I was elected a member of the AAS by the Council at this meeting, (7) I was already a member of the ASP, and this was my first opportunity to present a paper at an ASP meeting, and I could choose to put my abstract in the P.A.S.P., (8) I met many astronomers there who have been friends ever since, (9) along with many attendees I visited Butchart's Gardens, and (10) there was an excellent banquet at the Empress Hotel.

  18. Determination of firing distance. Lead analysis on the target by atomic absorption spectroscopy (AAS).

    PubMed

    Gagliano-Candela, Roberto; Colucci, Anna P; Napoli, Salvatore

    2008-03-01

    This paper reports a method for the determination of the firing distance. Atomic absorption spectroscopy (AAS) was used to determine the lead (Pb) pattern around bullet holes produced by shots on test targets from the gun. Test shots were made with a Colt 38 Special at 5, 10, 20, 25, 30, 35, 40, 45, 50, 60, 80, and 100 cm target distance. The target was created with sheets of Whatman no. 1 paper on a polystyrene support. The target was subdivided into three carefully cut out rings (1, 2, and 3; with external diameters of 1.4 cm; 5 cm; 10.2 cm, respectively). Each sample was analyzed with graphite furnace AAS. Lead values analysis performed for each ring yielded a linear relation between the firing distance (cm) and the logarithm of lead amounts (microg/cm(2)) in definite target areas (areas 2 + 3): [ln dPb(2+3) = a(0) + a(1)l]; where dPb(2+3) = lead microg/cm(2) of area 2 + 3; a(0) and a(1) are experimentally calculated; l = distance in cm.

  19. Change of Hot Cracking Susceptibility in Welding of High Strength Aluminum Alloy AA 7075

    NASA Astrophysics Data System (ADS)

    Holzer, M.; Hofmann, K.; Mann, V.; Hugger, F.; Roth, S.; Schmidt, M.

    High strength aluminum alloys are known as hard to weld alloys due to their high hot crack susceptibility. However, they have high potential for applications in light weight constructions of automotive industry and therefore it is needed to increase weldability. One major issue is the high hot cracking susceptibility. Vaporization during laser beam welding leads to a change of concentration of the volatile elements magnesium and zinc. Hence, solidification range of the weld and therefore hot cracking susceptibility changes. Additionally, different welding velocities lead to changed solidification conditions with certain influence on hot cracking. This paper discusses the influence of energy per unit length during laser beam welding of AA 7075 on the change of element concentration in the weld seam and the resulting influence on hot cracking susceptibility. Therefore EDS-measurements of weld seams generated with different velocities are performed to determine the change of element concentration. These quantitative data is used to numerically calculate the solidification range in order to evaluate its influence on the hot cracking susceptibility. Besides that, relative hot crack length and mechanical properties are measured. The results increase knowledge about welding of high strength aluminum alloy AA 7075 and hence support further developing of the welding process.

  20. Relationships of wild and domesticated rices (Oryza AA genome species) based upon whole chloroplast genome sequences.

    PubMed

    Wambugu, Peterson W; Brozynska, Marta; Furtado, Agnelo; Waters, Daniel L; Henry, Robert J

    2015-09-10

    Rice is the most important crop in the world, acting as the staple food for over half of the world's population. The evolutionary relationships of cultivated rice and its wild relatives have remained contentious and inconclusive. Here we report on the use of whole chloroplast sequences to elucidate the evolutionary and phylogenetic relationships in the AA genome Oryza species, representing the primary gene pool of rice. This is the first study that has produced a well resolved and strongly supported phylogeny of the AA genome species. The pan tropical distribution of these rice relatives was found to be explained by long distance dispersal within the last million years. The analysis resulted in a clustering pattern that showed strong geographical differentiation. The species were defined in two primary clades with a South American/African clade with two species, O glumaepatula and O longistaminata, distinguished from all other species. The largest clade was comprised of an Australian clade including newly identified taxa and the African and Asian clades. This refined knowledge of the relationships between cultivated rice and the related wild species provides a strong foundation for more targeted use of wild genetic resources in rice improvement and efforts to ensure their conservation.

  1. Relationships of wild and domesticated rices (Oryza AA genome species) based upon whole chloroplast genome sequences

    PubMed Central

    Wambugu, Peterson W.; Brozynska, Marta; Furtado, Agnelo; Waters, Daniel L.; Henry, Robert J.

    2015-01-01

    Rice is the most important crop in the world, acting as the staple food for over half of the world’s population. The evolutionary relationships of cultivated rice and its wild relatives have remained contentious and inconclusive. Here we report on the use of whole chloroplast sequences to elucidate the evolutionary and phylogenetic relationships in the AA genome Oryza species, representing the primary gene pool of rice. This is the first study that has produced a well resolved and strongly supported phylogeny of the AA genome species. The pan tropical distribution of these rice relatives was found to be explained by long distance dispersal within the last million years. The analysis resulted in a clustering pattern that showed strong geographical differentiation. The species were defined in two primary clades with a South American/African clade with two species, O glumaepatula and O longistaminata, distinguished from all other species. The largest clade was comprised of an Australian clade including newly identified taxa and the African and Asian clades. This refined knowledge of the relationships between cultivated rice and the related wild species provides a strong foundation for more targeted use of wild genetic resources in rice improvement and efforts to ensure their conservation. PMID:26355750

  2. Coexpression of chitinase and the cry11Aa1 toxin genes in Bacillus thuringiensis serovar israelensis.

    PubMed

    Sirichotpakorn, N; Rongnoparut, P; Choosang, K; Panbangred, W

    2001-10-01

    At the spore stage, a cloned chitinase gene was coexpressed with the regulatory gene p19 and the toxin gene cry11Aa1 in the hosts Bacillus thuringiensis serovar israelensis strains 4Q2-72 and c4Q2-72. The chitinase gene was derived from a high-chitinase producer, Bacillus licheniformis TP-1. Two transcriptional fusion plasmids between the p19 or p19-cry11Aa1 genes and the promoterless chitinase gene were constructed. In transcription order, the p16-19CHI construct contained the p19 gene together with the chitinase gene only while the p16-1968CHI construct contained p19 together with the toxin gene cry11Aa1 and the chitinase gene. The inserted sequences were regulated by a spore-specific promoter located upstream of p19. The recombinant chitinase of all transformed B. thuringiensis serovar israelensis strains was initially synthesized at low level at about 9 h of growth when a portion of the cells started to sporulate. It increased thereafter and reached maximum levels of 5.5, 4.9, and 4.7 mU/ml at 48 h, for strain 4Q2-72 transformed with p16-19CHI and p16-1968CHI and strain c4Q2-72 transformed with p16-19CHI, respectively. This activity was approximately 2 times higher than the maximum activity (2.7 mU/ml) of the parental strain, B. licheniformis TP-1. Although crude chitinase alone from B. thuringiensis serovar israelensis c4Q2-72 (p16-19CHI) at 4.5 mU/ml caused 40% mortality in second instar Aedes aegypti larvae, transformants containing the chitinase alone or in combination with cry11Aa1 resulted in lower toxicity to A. aegypti larvae than the untransformed 4Q2-72 host. For example the LC(50) for the transformed 4Q2-72 harboring the chitinase gene only (p16-19CHI) was 5.6 x 10(4) +/- 0.7 x 10(4) cells, 40 times higher than that of the untransformed host at 1.4 x 10(3) +/- 0.19 x 10(3). The lower toxicity correlated with poor sporulation in the transformants (i.e., 35 times lower than that in the untransformed host). However, the transformed 4Q2-72 strain

  3. Investigation into the stress corrosion cracking properties of AA2099, an aluminum-lithium-copper alloy

    NASA Astrophysics Data System (ADS)

    Padgett, Barbara Nicole

    Recently developed Al-Li-Cu alloys show great potential for implementation in the aerospace industry because of the attractive mix of good mechanical properties and low density. AA2099 is an Al-Li-Cu alloy with the following composition Al-2.69wt%Cu-1.8wt%Li-0.6wt%Zn-0.3wt%Mg-0.3wt%Mn-0.08wt%Zr. The environmental assisted cracking and localized corrosion behavior of the AA2099 was investigated in this thesis. The consequences of uncontrolled grain boundary precipitation via friction stir welding on the stress corrosion cracking (SCC) behavior of AA2099 was investigated first. Using constant extension rate testing, intergranular corrosion immersion experiments, and potentiodynamic scans, the heat-affected zone on the trailing edge of the weld (HTS) was determined to be most susceptible of the weld zones. The observed SCC behavior for the HTS was linked to the dissolution of an active phase (Al2CuLi, T1) populating the grain boundary. It should be stated that the SCC properties of AA2099 in the as-received condition were determined to be good. Focus was then given to the electrochemical behavior of precipitate phases that may occupy grain and sub-grain boundaries in AA2099. The grain boundary micro-chemistry and micro-electrochemistry have been alluded to within the literature as having significant influence on the SCC behavior of Al-Li-Cu alloys. Major precipitates found in this alloy system are T1 (Al 2CuLi), T2 (Al7.5Cu4Li), T B (Al6CuLi3), and theta (Al2 Cu). These phases were produced in bulk form so that the electrochemical nature of each phase could be characterized. It was determined T1 was most active electrochemically and theta was least. When present on grain boundaries in the alloy, electrochemical behavior of the individual precipitates aligned with the observed corrosion behavior of the alloy (e.g. TB was accompanied by general pitting corrosion and T 1 was accompanied by intergranular corrosion attack). In addition to the electrochemical behavior of

  4. Hematotoxicity and genotoxicity evaluations in Swiss mice intraperitoneally exposed to Bacillus thuringiensis (var kurstaki) spore crystals genetically modified to express individually Cry1Aa, Cry1Ab, Cry1Ac, or Cry2Aa.

    PubMed

    Mezzomo, Bélin Poletto; Miranda-Vilela, Ana Luisa; Barbosa, Lilian Carla Pereira; Albernaz, Vanessa Lima; Grisolia, Cesar Koppe

    2016-08-01

    Bacillus thuringiensis (Bt) has been widely used in foliar sprays as part of integrated pest management strategies against insect pests of agricultural crops. Since the advent of genetically modified plants expressing Bt δ-endotoxins, the bioavailability of Cry proteins has increased, and therefore for biosafety reasons their adverse effects should be studied, mainly for nontarget organisms. We evaluated, in Swiss mice, the hematotoxicity and genotoxicity of the genetically modified strains of Bt spore crystals Cry1Aa, 1Ab, 1Ac, or 2Aa at 27 mg/kg, and Cry1Aa, 1Ab and 2Aa also at 136 and 270 mg/kg, administered with a single intraperitoneal injection 24 h before euthanasia. Controls received filtered water or cyclophosphamide. Blood samples collected by cardiac puncture were used to perform hemogram, and bone marrow was extracted for the micronucleus test. Bt spore crystals presented toxicity for lymphocytes when in higher doses, which varied according to the type of spore crystal studied, besides promoting cytotoxic and genotoxic effects for the erythroid lineage of bone marrow, mainly at highest doses. Although the profile of such adverse side effects can be related to their high level of exposure, which is not commonly found in the environment, results indicated that these Bt spore crystals were not harmless to mice. This suggests that a more specific approach should be taken to increase knowledge about their toxicological properties and to establish the toxicological risks to nontarget organisms. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 970-978, 2016.

  5. The AaO as Building Block in the Coupling of Text Kinematics with the Resonating Structure of a Metaphor.

    ERIC Educational Resources Information Center

    Bierschenk, Bernhard; Bierschenk, Inger

    The Agent-action-Objective (AaO) axiom and the theory of rotational dynamics constitute the frame of reference for the study of the metaphor as instrument for the direct perception of events. The major hypothesis of this frame of reference refers to the event structure embedded in the ground of a metaphor. Since the ground is implicit in the…

  6. Alcohol-preferring (AA) and alcohol-avoiding (ANA) lines of rats after introgression of alien genes.

    PubMed

    Hyytiä, P; Halkka, O; Sarviharju, M; Eriksson, K

    1987-01-01

    Outcrossing has been used as a method for introducing new genetic variability into the high-drinking AA and low-drinking ANA rat lines that had reached their selection limits and were suffering of poor fertility and decreased litter size. The response to the renewed selection for differential alcohol consumption, and the effect of outcrossing upon the components of productivity are reported.

  7. Production of polyclonal and monoclonal antibodies against the Bacillus thuringiensis vegetative insecticidal protein Vip3Aa16.

    PubMed

    Ben Hamadou-Charfi, Dorra; Sauer, Annette Juliane; Abdelkafi-Mesrati, Lobna; Jaoua, Samir; Stephan, Dietrich

    2015-03-01

    The aim of this study is to establish a quantitative determination of the vegetative insecticidal protein Vip3A from the culture supernatant of Bacillus thuringiensis either by ELISA or by the conventional quantification method of the Western blot band. The Vip3A protein was produced by fermentation of the B. thuringiensis reference strain BUPM95 in 3 L. By Western blot, the Vip3Aa16 toxin was detected in the culture supernatant during the exponential growth phase of B. thuringiensis BUPM95. However, the detection of Vip3Aa16 on Western blot showed in addition to the toxin two other strips (62 and 180 kDa) recognized by the anti-Vip3Aa16 polyclonal antibodies prepared at the Centre of Biotechnology of Sfax Tunisia. For that reason and in order to develop a technique for reliable quantification of the toxin, we have considered the production of polyclonal antibodies at the Julius Kühn Institute, Germany. These antibodies were the basis for the production of monoclonal antibodies directed against the protein produced by the Vip3Aa16 recombinant strain Escherichia coli BL21 (DE3). These monoclonal antibodies were tested by plate-trapped antigen (PTA) and triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA). The selection of hybridoma supernatants gave us four positive clones producing monoclonal antibodies.

  8. Updates to the p+p and A+A chemical freeze-out lines from the new experimental data

    NASA Astrophysics Data System (ADS)

    Begun, V. V.; Vovchenko, V.; Gorenstein, M. I.

    2017-01-01

    We show that the new data on mean multiplicities measured in p+p and A+A collisions together with the updated list of resonances lead to the significant changes of the obtained freeze-out lines. The new A+A line gives much smaller temperatures at high collision energies and agrees with the values obtained at the LHC. The newly obtained p+p line is much closer to the A+A line than previously expected, and even touches it in the region where the K + /π + horn appears in the data. It indicates that the temperatures that will be obtained in the beam energy and system size scan by the NA61/SHINE Collaboration might be very close. However, our analysis shows that the chemical potentials could be very different for the same energies in A+A and p+p. It adds more puzzles to the set of surprising coincidences at the energies close to the possible onset of deconfinement.

  9. 8. Public Works Department (PWD) Drawing 10,0041(463AA1)(1936), 'Extension to Bldg ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Public Works Department (PWD) Drawing 10,004-1(463A-A-1)(1936), 'Extension to Bldg 463-Plan and Elevations' - Mare Island Naval Shipyard, Battery Test Office & Storage Facility, California Avenue & E Street, Vallejo, Solano County, CA

  10. A P-Glycoprotein Is Linked to Resistance to the Bacillus thuringiensis Cry3Aa Toxin in a Leaf Beetle

    PubMed Central

    Pauchet, Yannick; Bretschneider, Anne; Augustin, Sylvie; Heckel, David G.

    2016-01-01

    Chrysomela tremula is a polyvoltine oligophagous leaf beetle responsible for massive attacks on poplar trees. This beetle is an important model for understanding mechanisms of resistance to Bacillus thuringiensis (Bt) insecticidal toxins, because a resistant C. tremula strain has been found that can survive and reproduce on transgenic poplar trees expressing high levels of the Cry3Aa Bt toxin. Resistance to Cry3Aa in this strain is recessive and is controlled by a single autosomal locus. We used a larval midgut transcriptome for C. tremula to search for candidate resistance genes. We discovered a mutation in an ABC protein, member of the B subfamily homologous to P-glycoprotein, which is genetically linked to Cry3Aa resistance in C. tremula. Cultured insect cells heterologously expressing this ABC protein swell and lyse when incubated with Cry3Aa toxin. In light of previous findings in Lepidoptera implicating A subfamily ABC proteins as receptors for Cry2A toxins and C subfamily proteins as receptors for Cry1A and Cry1C toxins, this result suggests that ABC proteins may be targets of insecticidal three-domain Bt toxins in Coleoptera as well. PMID:27929397

  11. Bacillus thuringiensis Cry3Aa protoxin intoxication of Tenebrio molitor induces widespread changes in the expression of serine peptidase transcripts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The yellow mealworm, Tenebrio molitor, is a pest of stored grain products and is sensitive to the coleopteran-specific Cry3Aa toxin from Bacillus thuringiensis (Bt). Larvae digest protein initially with cysteine peptidases in the anterior midgut and further with serine peptidases in middle and poste...

  12. Cell cycle arrest and biochemical changes accompanying cell death in harmful dinoflagellates following exposure to bacterial algicide IRI-160AA

    PubMed Central

    Pokrzywinski, Kaytee L.; Tilney, Charles L.; Warner, Mark E.; Coyne, Kathryn J.

    2017-01-01

    Bacteria may play a role in regulating harmful algal blooms, but little is known about the biochemical and physiological changes associated with cell death induced by algicidal bacteria. Previous work characterized an algicidal exudate (IRI-160AA) produced by Shewanella sp. IRI-160 that is effective against dinoflagellates, while having little to no effect on other phytoplankton species in laboratory culture experiments. The objective of this study was to evaluate biochemical changes associated with cell death and impacts on the cell cycle in three dinoflagellate species (Prorocentrum minimum, Karlodinium veneficum and Gyrodinium instriatum) after exposure to IRI-160AA. In this study, IRI-160AA induced cell cycle arrest in all dinoflagellates examined. Several indicators for programmed cell death (PCD) that are often observed in phytoplankton in response to a variety of stressors were also evaluated. Cell death was accompanied by significant increases in DNA degradation, intra- and extracellular ROS concentrations and DEVDase (caspase-3 like) protease activity, which have been associated with PCD in other phytoplankton species. Overall, results of this investigation provide strong evidence that treatment with the bacterial algicide, IRI-160AA results in cell cycle arrest and induces biochemical changes consistent with stress-related cell death responses observed in other phytoplankton. PMID:28332589

  13. Development of bovine embryos cultured in CR1aa and IVD101 media using different oxygen tensions and culture systems.

    PubMed

    Somfai, Tamás; Inaba, Yasushi; Aikawa, Yoshio; Ohtake, Masaki; Kobayashi, Shuji; Konishi, Kazuyuki; Nagai, Takashi; Imai, Kei

    2010-12-01

    The aim of the present study was to optimise the culture conditions for the in vitro production of bovine embryos. The development of in vitro fertilised bovine oocytes in CR1aa supplemented with 5% calf serum and IVD101 culture media were compared using traditional microdrops and Well of the Well (WOW) culture systems either under 5% or 20% oxygen tension. After 7 days of culture, a significantly higher blastocyst formation rate was obtained for embryos cultured in CR1aa medium compared to those cultured in IVD101, irrespective of O2 tensions and culture systems. The blastocyst formation in IVD101 was suppressed under 20% O2 compared to 5% O2 . Despite their similar total cell numbers, higher rates of inner cell mass (ICM) cells were observed in blastocysts developed in IVD101 medium than in those developed in CR1aa, irrespective of O2 tensions. There was no significant difference in blastocyst formation, total, ICM and trophectoderm (TE) cell numbers between embryos obtained by microdrop and WOW culture systems irrespective of the culture media and O2 tensions used. In conclusion, CR1aa resulted in higher blastocyst formation rates irrespective of O2 tension, whereas IVD101 supported blastocyst formation only under low O2 levels but enhanced the proliferation of ICM cells.

  14. Bt-Cry3Aa expression reduces insect damage and improves growth in field-grown hybrid poplar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated growth and insect resistance in hybrid poplar expressing the cry3Aa gene in two field trials. An initial screening of 502 trees comprising 51 transgenic gene insertion events in four clonal backgrounds (Populus trichocarpa x P. deltoides, clones 24-305, 50-197, and 198-434; and P. d...

  15. 13. Naval Facilities (NAVFAC) Engineering Command Drawing 1,174,310(463AA3)(1970), 'Alterations for ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Naval Facilities (NAVFAC) Engineering Command Drawing 1,174,310(463A-A-3)(1970), 'Alterations for Laboratory Facility-Architectural' - Mare Island Naval Shipyard, Battery Test Office & Storage Facility, California Avenue & E Street, Vallejo, Solano County, CA

  16. Modification of Cry4Aa toward Improved Toxin Processing in the Gut of the Pea Aphid, Acyrthosiphon pisum

    PubMed Central

    Rausch, Michael A.; Chougule, Nanasaheb P.; Deist, Benjamin R.; Bonning, Bryony C.

    2016-01-01

    Aphids are sap-sucking insects (order: Hemiptera) that cause extensive damage to a wide range of agricultural crops. Our goal was to optimize a naturally occurring insecticidal crystalline (Cry) toxins produced by the soil-dwelling bacterium Bacillus thuringiensis for use against the pea aphid, Acyrthosiphon pisum. On the basis that activation of the Cry4Aa toxin is a rate-limiting factor contributing to the relatively low aphicidal activity of this toxin, we introduced cathepsin L and cathepsin B cleavage sites into Cry4Aa for rapid activation in the aphid gut environment. Incubation of modified Cry4Aa and aphid proteases in vitro demonstrated enhanced processing of the toxin into the active form for some of the modified constructs relative to non-modified Cry4Aa. Aphids fed artificial diet with toxin at a final concentration of 125 μg/ml showed enhanced mortality after two days for one of the four modified constructs. Although only modest toxin improvement was achieved by use of this strategy, such specific toxin modifications designed to overcome factors that limit aphid toxicity could be applied toward managing aphid populations via transgenic plant resistance. PMID:27171411

  17. IFNγ production in peripheral blood of early Lyme disease patients to hLFAαL (aa326-345)

    PubMed Central

    Gomes-Solecki, Maria JC; Wormser, Gary P; Dattwyler, Raymond J

    2002-01-01

    Background It has been proposed that outer surface protein A (OspA) of Borrelia burgdorferi sensu stricto contains a T helper 1 (Th1) cell epitope that could play a role in an autoimmune response to hLFA1. Methods We used two peptides, hLFAαL (aa326-345) and Borrelia burgdorferi OspAB31 (aa164-183), as stimulating antigens to measure Th1 proinflammatory IFNγ cytokine production in peripheral blood of Lyme disease patients presenting with EM without history of arthritis, as well as in peripheral blood of healthy individuals. Results IFNγ responses to hLFA1 peptide were observed in 11 of 19 Lyme disease patients and in 3 of 15 healthy controls. In contrast, only 2 of 19 of the Lyme disease patients and none of the controls responded to the homologous OspAB31 peptide. Conclusions IFNγ was produced in response to stimulation with peptide hLFAαL (aa326-345) in peripheral blood of 58% of patients with early Lyme disease without signs of arthritis, as well as in peripheral blood of 20% of healthy individuals, but not in response to stimulation with the homologous OspAB31 (aa164-183) peptide (p < 0.05). Our results suggest that reactivity to the hLFA1 peptide in peripheral blood may be the result of T cell degeneracy. PMID:12385648

  18. Cell cycle arrest and biochemical changes accompanying cell death in harmful dinoflagellates following exposure to bacterial algicide IRI-160AA

    NASA Astrophysics Data System (ADS)

    Pokrzywinski, Kaytee L.; Tilney, Charles L.; Warner, Mark E.; Coyne, Kathryn J.

    2017-03-01

    Bacteria may play a role in regulating harmful algal blooms, but little is known about the biochemical and physiological changes associated with cell death induced by algicidal bacteria. Previous work characterized an algicidal exudate (IRI-160AA) produced by Shewanella sp. IRI-160 that is effective against dinoflagellates, while having little to no effect on other phytoplankton species in laboratory culture experiments. The objective of this study was to evaluate biochemical changes associated with cell death and impacts on the cell cycle in three dinoflagellate species (Prorocentrum minimum, Karlodinium veneficum and Gyrodinium instriatum) after exposure to IRI-160AA. In this study, IRI-160AA induced cell cycle arrest in all dinoflagellates examined. Several indicators for programmed cell death (PCD) that are often observed in phytoplankton in response to a variety of stressors were also evaluated. Cell death was accompanied by significant increases in DNA degradation, intra- and extracellular ROS concentrations and DEVDase (caspase-3 like) protease activity, which have been associated with PCD in other phytoplankton species. Overall, results of this investigation provide strong evidence that treatment with the bacterial algicide, IRI-160AA results in cell cycle arrest and induces biochemical changes consistent with stress-related cell death responses observed in other phytoplankton.

  19. A P-Glycoprotein Is Linked to Resistance to the Bacillus thuringiensis Cry3Aa Toxin in a Leaf Beetle.

    PubMed

    Pauchet, Yannick; Bretschneider, Anne; Augustin, Sylvie; Heckel, David G

    2016-12-05

    Chrysomela tremula is a polyvoltine oligophagous leaf beetle responsible for massive attacks on poplar trees. This beetle is an important model for understanding mechanisms of resistance to Bacillus thuringiensis (Bt) insecticidal toxins, because a resistant C. tremula strain has been found that can survive and reproduce on transgenic poplar trees expressing high levels of the Cry3Aa Bt toxin. Resistance to Cry3Aa in this strain is recessive and is controlled by a single autosomal locus. We used a larval midgut transcriptome for C. tremula to search for candidate resistance genes. We discovered a mutation in an ABC protein, member of the B subfamily homologous to P-glycoprotein, which is genetically linked to Cry3Aa resistance in C. tremula. Cultured insect cells heterologously expressing this ABC protein swell and lyse when incubated with Cry3Aa toxin. In light of previous findings in Lepidoptera implicating A subfamily ABC proteins as receptors for Cry2A toxins and C subfamily proteins as receptors for Cry1A and Cry1C toxins, this result suggests that ABC proteins may be targets of insecticidal three-domain Bt toxins in Coleoptera as well.

  20. Molecular Characteristic, Protein Distribution and Potential Regulation of HSP90AA1 in the Anadromous Fish Coilia nasus

    PubMed Central

    Fang, Di-An; Duan, Jin-Rong; Zhou, Yan-Feng; Zhang, Min-Ying; Xu, Dong-Po; Liu, Kai; Xu, Pao

    2016-01-01

    Heat shock proteins play essential roles in basic cellular events. Spawning migration is a complex process, with significant structural and biochemical changes taking place in the adult gonad. To date, the molecular mechanisms underlying migration reproductive biology remain undetermined. In this regard, a full length HSP90AA1 comprising 2608 nucleotides from the anadromous fish Coilia nasus was characterized, encoding 742 amino acid (aa) residues with potential phosphorylation sites. HSP90AA1 mRNA transcripts were detected in all organs, especially in the gonad. Furthermore, the greatest transcript levels were found during the developmental phase, while the lowest levels were found during the resting phase. In addition, the strongest immunolabeling positive signal was found in the primary spermatocyte and oocyte, with lower positive staining in secondary germ cells, and a weak or absent level in the mature sperm and oocyte. Interestingly, HSP90AA1 was mainly located in the cytoplasm of germ cells. These results are important for understanding the molecular mechanism of anadromous migration reproductive biology. In combination with data from other fish species, the result of this present study may facilitate further investigations on the spawning migration mechanism. PMID:26828521

  1. Single-molecule force spectroscopy studies of fibrin 'A-a' polymerization interactions via the atomic force microscope

    NASA Astrophysics Data System (ADS)

    Averett, Laurel E.

    Fibrin, the polymerized form of the soluble plasma protein fibrinogen, plays a critical role in hemostasis as the structural scaffold of blood clots. The primary functions of fibrin are to withstand the shear forces of blood flow and provide mechanical stability to the clot, protecting the wound. While studies have investigated the mechanical properties of fibrin constructs, the response to force of critical polymerization interactions such as the 'A--a' knob--hole interaction remains unclear. Herein, the response of the 'A--a' bond to force was examined at the single-molecule level using the atomic force microscope. Force spectroscopy methodology was developed to examine the 'A--a' interaction while reducing the incidence of both nonspecific and multiple molecule interactions. The rupture of this interaction resulted in a previously unreported characteristic force profile comprised of up to four events. We hypothesized that the first event represented reorientation of the fibrinogen molecule, the second and third represented unfolding of structures in the D region of fibrinogen, and the last event was the rupture of the 'A--a' bond weakened by prior structural unfolding. The configuration, molecular extension, and kinetic parameters of each event in the characteristic pattern were examined to compare the unfolding of fibrin to other proteins unfolded by force. Fitting the pattern with polymer models showed that the D region of fibrinogen could lengthen by ˜50% of the length of a fibrin monomer before rupture of the 'A--a' bond. Analysis showed that the second and third events had kinetic parameters similar to other protein structures unfolded by force. Studies of the dependence of the characteristic pattern on calcium, concentration of sodium chloride, pH, and temperature demonstrated that the incidence of the last event was affected by solution conditions. However, only low pH and high temperatures reduced the probability that an interaction was characteristic

  2. Anabolic Androgenic Steroid (AAS) related deaths: autoptic, histopathological and toxicological findings.

    PubMed

    Frati, Paola; Busardò, Francesco P; Cipolloni, Luigi; Dominicis, Enrico De; Fineschi, Vittorio

    2015-01-01

    Anabolic androgenic steroids (AASs) represent a large group of synthetic derivatives of testosterone, produced to maximize anabolic effects and minimize the androgenic ones. AAS can be administered orally, parenterally by intramuscular injection and transdermally. Androgens act by binding to the nuclear androgen receptor (AR) in the cytoplasm and then translocate into the nucleus. This binding results in sequential conformational changes of the receptor affecting the interaction between receptor and protein, and receptor and DNA. Skeletal muscle can be considered as the main target tissue for the anabolic effects of AAS, which are mediated by ARs which after exposure to AASs are up-regulated and their number increases with body building. Therefore, AASs determine an increase in muscle size as a consequence of a dose-dependent hypertrophy resulting in an increase of the cross-sectional areas of both type I and type II muscle fibers and myonuclear domains. Moreover, it has been reported that AASs can increase tolerance to exercise by making the muscles more capable to overload therefore shielding them from muscle fiber damage and improving the level of protein synthesis during recovery. Despite some therapeutic use of AASs, there is also wide abuse among athletes especially bodybuilders in order to improve their performances and to increase muscle growth and lean body mass, taking into account the significant anabolic effects of these drugs. The prolonged misuse and abuse of AASs can determine several adverse effects, some of which may be even fatal especially on the cardiovascular system because they may increase the risk of sudden cardiac death (SCD), myocardial infarction, altered serum lipoproteins, and cardiac hypertrophy. The aim of this review is to focus on deaths related to AAS abuse, trying to evaluate the autoptic, histopathological and toxicological findings in order to investigate the pathophysiological mechanism that underlines this type of death, which

  3. Transgenic plants expressing the AaIT/GNA fusion protein show increased resistance and toxicity to both chewing and sucking pests.

    PubMed

    Liu, Shu-Min; Li, Jie; Zhu, Jin-Qi; Wang, Xiao-Wei; Wang, Cheng-Shu; Liu, Shu-Sheng; Chen, Xue-Xin; Li, Sheng

    2016-04-01

    The adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. To achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, Arabidopsis, and rice plants expressing the fusion protein, AaIT/GNA, in which an insecticidal scorpion venom neurotoxin (Androctonus australis toxin, AaIT) is fused to snowdrop lectin (Galanthus nivalis agglutinin, GNA). Compared with transgenic tobacco and Arabidopsis plants expressing AaIT or GNA, transgenic plants expressing AaIT/GNA exhibited increased resistance and toxicity to one chewing pest, the cotton bollworm, Helicoverpa armigera. Transgenic tobacco and rice plants expressing AaIT/GNA showed increased resistance and toxicity to two sucking pests, the whitefly, Bemisia tabaci, and the rice brown planthopper, Nilaparvata lugens, respectively. Moreover, in the field, transgenic rice plants expressing AaIT/GNA exhibited a significant improvement in grain yield when infested with N. lugens. This study shows that expressing the AaIT/GNA fusion protein in transgenic plants can be a useful approach for controlling pests, particularly sucking pests which are not susceptible to the toxin in Bt crops.

  4. The expression and crystallization of Cry65Aa require two C-termini, revealing a novel evolutionary strategy of Bacillus thuringiensis Cry proteins

    PubMed Central

    Peng, Dong-hai; Pang, Cui-yun; Wu, Han; Huang, Qiong; Zheng, Jin-shui; Sun, Ming

    2015-01-01

    The insecticidal crystal protein (Cry) genes of Bacillus thuringiensis are a key gene resource for generating transgenic crops with pest resistance. However, many cry genes cannot be expressed or form crystals in mother cells. Here, we report a novel Cry protein gene, cry65Aa1, which exists in an operon that contains a downstream gene encoding a hypothetical protein ORF2. We demonstrated that ORF2 is required for Cry65Aa1 expression and crystallization by function as a C-terminal crystallization domain. The orf2 sequence is also required for Cry65Aa expression, because orf2 transcripts have a stabilizing effect on cry65Aa1 transcripts. Furthermore, we found that the crystallization of Cry65Aa1 required the Cry65Aa1 C-terminus in addition to ORF2 or a typical Cry protein C-terminal region. Finally, we showed that Cry65Aa1 has a selective cytotoxic effect on MDA-MB231 cancer cells. This report is the first description of a 130-kDa mass range Cry protein requiring two C-termini for crystallization. Our findings reveal a novel evolutionary strategy of Cry proteins and provide an explanation for the existence of Cry protein genes that cannot form crystals in B. thuringiensis. This study also provides a potential framework for isolating novel cry genes from “no crystal” B. thuringiensis strains. PMID:25656389

  5. Molecular cloning and promoter analysis of the specific salicylic acid biosynthetic pathway gene phenylalanine ammonia-lyase (AaPAL1) from Artemisia annua.

    PubMed

    Zhang, Ying; Fu, Xueqing; Hao, Xiaolong; Zhang, Lida; Wang, Luyao; Qian, Hongmei; Zhao, Jingya

    2016-07-01

    Phenylalanine ammonia-lyase (PAL) is the key enzyme in the biosynthetic pathway of salicylic acid (SA). In this study, a full-length cDNA of PAL gene (named as AaPAL1) was cloned from Artemisia annua. The gene contains an open reading frame of 2,151 bps encoding 716 amino acids. Comparative and bioinformatics analysis revealed that the polypeptide protein of AaPAL1 was highly homologous to PALs from other plant species. Southern blot analysis revealed that it belonged to a gene family with three members. Quantitative RT-PCR analysis of various tissues of A. annua showed that AaPAL1 transcript levels were highest in the young leaves. A 1160-bp promoter region was also isolated resulting in identification of distinct cis-regulatory elements including W-box, TGACG-motif, and TC-rich repeats. Quantitative RT-PCR indicated that AaPAL1 was upregulated by salinity, drought, wounding, and SA stresses, which were corroborated positively with the identified cis-elements within the promoter region. AaPAL1 was successfully expressed in Escherichia. coli and the enzyme activity of the purified AaPAL1 was approximately 287.2 U/mg. These results substantiated the involvement of AaPAL1 in the phenylalanine pathway.

  6. Accumbal FosB/DeltaFosB immunoreactivity and conditioned place preference in alcohol-preferring AA rats and alcohol-avoiding ANA rats treated repeatedly with cocaine.

    PubMed

    Marttila, Kristiina; Petteri Piepponen, T; Kiianmaa, Kalervo; Ahtee, Liisa

    2007-07-30

    Transcription factor DeltaFosB has been implicated in the psychomotor responses and rewarding effects of drugs of abuse. In the present study, we compared the effects of cocaine on the expression of DeltaFosB-like proteins by immunohistochemistry in striatal brain areas of alcohol-preferring (AA) and alcohol-avoiding (ANA) rats. Cocaine was administered using a previously verified treatment paradigm that sensitized the locomotor response to cocaine in AA but not in ANA rats. We also studied the rewarding effects of cocaine with a conditioned place preference (CPP) paradigm in both lines of rats. Cocaine treatment increased the FosB/DeltaFosB immunoreactivity (IR) in the nucleus accumbens of AA rats but not in ANA rats. In addition, after repeated saline injections the accumbal FosB/DeltaFosB IR was significantly greater in saline-injected AA rats than in ANA rats. In the caudate-putamen cocaine significantly increased FosB/DeltaFosB IR, but no differences were found between the rats of two lines. In the CPP experiment, AA rats treated with cocaine 2.5 mg/kg preferred the cocaine-associated compartment, in contrast to ANA rats, which did not show such a preference. In conclusion, our findings show that AA rats are more sensitive to cocaine than ANA rats, and suggest that one possible mediator for this increased sensitivity could be the increased expression of fosB-derived proteins in the nucleus accumbens of AA rats.

  7. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induced P-450 mediated arachidonic acid (AA) metabolism in chick embryo liver (CEL) occurs in parenchymal cells (PC) rather than in non-parenchymal cells (NPC)

    SciTech Connect

    Paroli, L.; Rifkind, A.B. )

    1992-02-26

    TCDD induces cytochrome P-450 mediated AA metabolism in CEL and changes the dominant metabolite(s) from {omega}-OH AA to AA epoxygenase products (EETs and EET-diols). PC and NPC from CEL were separated by differential centrifugation and characterized by morphology, immunohistochemistry and P-450 mediated xenobiotic metabolism; purities were >95%. PC and NPC, from 16 day old chick embryos treated for 5 days with TCDD or vehicle alone, were cultured for 48 hr, homogenized and incubated with ({sup 14}C)-AA {plus minus} NADPH. AA products were resolved by reverse phase HPLC. The major product in control PC, {omega}-OH AA was not significantly affected by TCDD. All of the AA metabolism was NADPH dependent. Control and TCDD treated PC had the same metabolite patterns as whole liver microsomes. Neither control nor TCDD treated NPC generated P-450 AA metabolites. Also co-culturing NPC with PC did not affect AA metabolism of either cell type. The findings indicate that TCDD-induced changes in AA metabolism are retained in culture and that hepatocytes rather than NPC effect P-450 mediated AA metabolism in both control and TCDD-induced CEL.

  8. Cyclic AMP regulation of arachidonic acid (AA) release and phospholipid metabolism in human monocytes: modulation by intracellular calcium

    SciTech Connect

    Hoffstein, S.T.; Manzi, R.M.; Godfrey, R.W.

    1986-05-01

    Stimulation of inflammatory cells by specific ligands results in activation of phospholipase(s) and production of oxygenation products of AA. The authors have employed (/sup 3/H)AA labeled monocytes to examine the involvement of cAMP in regulating phospholipase activity as measured by percent of incorporated (/sup 3/H)AA released and TLC analysis of (/sup 3/H)AA cellular lipids. Maximum release of radiolabel (31 +/- 5%) occurred upon challenge with the calcium ionophore A23187/sup -/ (10..mu..M), while FMLP (1..mu..M) yielded 15 +/- 1% and untreated cells 8 +/- 1%. Pretreatment of monocytes with isobutyl methyl xanthine/sup -/(IBMX) or dibutyrl cyclic AMP (d-cAMP) inhibited FMLP stimulated release with IC/sub 50/'s of 2.5 x 10/sup -5/M and 8 x 10/sup -5/M respectively. Exposure of monocytes to maximal levels of IBMX (5 x 10/sup -4/M) or d-cAMP (10/sup -3/M) also reduced release from controls by 40%, while A23187 induced release was uneffected by either. Examination of (/sup 3/H) AA labeled phospholipids showed that phosphatidylcholine (PC) and phosphatidylinositol were the major pools labeled and that stimulation by FMLP or A23187 appeared to deplete the PC pool exclusively. Prior exposure to IBMX or d-cAMP inhibited the loss from the PC pool only in untreated or FMLP stimulated cells. The data suggests that a phospholipase A/sub 2/ activity, directly primarily towards PC, is regulated by cAMP possibly by inhibiting receptor mediated increases in intracellular calcium levels.

  9. [Changes of CD34(+) and CD71(+)CD45(-) cell levels in bone marrow of MDS and AA patients].

    PubMed

    Yan, Zhen-Yu; Tian, Xu; Li, Ying; Yang, Mei-Rong; Zhang, Song; Wang, Xie-Ming; Zhang, Hai-Xia; Cheng, Nai-Yao

    2014-04-01

    This study was aimed to investigate the changes of CD34(+) and CD71(+)CD45(-) cell levels in MDS and AA patients. A total of 25 cases MDS and 43 cases of AA (18 cases SAA and 25 cases of NSAA) from January 2010 to October 2013 in the Department of Hematology, affiliated hospital of Hebei United University were enrolled in this study. The complete blood count, bone marrow smears, bone marrow biopsy, karyotype analysis and bone marrow blood cell immune genotyping (mainly the proportion of CD34(+) cells, CD71(+)CD45(-) cells in nucleated cells) were carried out for all patients; the changes of CD34(+) and CD71(+)CD45(-) cell levels in patients with MDS and AA (SAA NSAA) were compared; the differences of white blood cell count, platelet count and hemoglobin concentration in patients with count of CD71(+)CD45(-) ≥ 15% or <15% were analyzed. The results showed that the count of CD34(+) in MDS group was higher than that in AA (NSAA and SAA) group (P < 0.05). The count of CD71(+)CD45(-) cells in MDS group was higher than that in SAA (P < 0.05), there was no significant difference between NSAA group and MDS group. In MDS group with CD71(+)CD45(-) ≥ 15%, the platelet count was significantly higher than that in NSAA group (P < 0.05); and there was no statistical difference for leukocyte, platelet count and hemoglobin level between MDS and NSAA group with CD71(+)CD45(-) <15% (P > 0.05). It is concluded that the count of CD34(+) cells in MDS patients is significantly higher than that in AA and SAA patients. The count of CD71(+)CD45(-) cells in MDS group is significantly higher than that of SAA group. The platelet count in MDS patients with CD71(+)CD45(-) cells ≥ 15% is significantly higher than that of the NSAA group.

  10. Bacillus thuringiensis Cry1Ia10 and Vip3Aa protein interactions and their toxicity in Spodoptera spp. (Lepidoptera).

    PubMed

    Bergamasco, V B; Mendes, D R P; Fernandes, O A; Desidério, J A; Lemos, M V F

    2013-02-01

    The polyphagous pests belonging to the genus Spodoptera are considered to be among the most important causes of damage and are widely distributed throughout the Americas'. Due to the extensive use of genetically modified plants containing Bacillus thuringiensis genes that code for insecticidal proteins, resistant insects may arise. To prevent the development of resistance, pyramided plants, which express multiple insecticidal proteins that act through distinct mode of actions, can be used. This study analyzed the mechanisms of action for the proteins Cry1Ia10 and Vip3Aa on neonatal Spodoptera frugiperda, Spodoptera albula, Spodoptera eridania and Spodoptera cosmioides larvae. The interactions of these toxins with receptors on the intestinal epithelial membrane were also analyzed by binding biotinylated toxins to brush border membrane vesicles (BBMVs) from the intestines of these insects. A putative receptor of approximately 65 kDa was found by ligand blotting in all of these species. In vitro competition assays using biotinylated proteins have indicated that Vip3Aa and Cry1Ia10 do not compete for the same receptor for S. frugiperda, S. albula and S. cosmioides and that Vip3Aa was more efficient than Cry1Ia10 when tested individually, by bioassays. A synergistic effect of the toxins in S. frugiperda, S. albula and S. cosmioides was observed when they were combined. However, in S. eridania, Cry1Ia10 and Vip3Aa might compete for the same receptor and through bioassays Cry1Ia10 was more efficient than Vip3Aa and showed an antagonistic effect when the proteins were combined. These results suggest that using these genes to develop pyramided plants may not prove effective in preventing the development of resistance in S. eridiana.

  11. Associations of corticosterone and testosterone with alcohol drinking in F2 populations derived from AA and ANA rat lines.

    PubMed

    Etelälahti, Tiina J; Saarikoski, Sirkku T; Eriksson, C J Peter

    2011-08-01

    In our previous studies on alcohol-preferring AA (Alko alcohol) and nonpreferring ANA (Alko nonalcohol) rats, we have observed that the AA rats exhibit lower endogenous levels of corticosterone, higher testosterone levels, and more frequent alcohol-induced testosterone elevations when compared with ANA rats. The objective of the present study was to get more conclusive evidence for the potential role of the hypothalamus-pituitary-adrenal and hypothalamus-pituitary-gonadal axes in alcohol drinking by using the F2 experimental design. Alcohol-preferring AA and alcohol-nonpreferring ANA rat lines were crossbred to form a F1 population from which the final F2 population was derived. Male animals were challenged with a priming alcohol dose after which a 3 weeks' voluntary alcohol drinking period took place. After a washout period of 1 week, one-half of the 40 highest and 40 lowest alcohol drinkers were challenged with a second dose of alcohol and the other half with saline. Serum testosterone and corticosterone levels were measured before and during the test. Higher endogenous testosterone levels were detected in the rats of the high alcohol consumption group compared with the low consumption group. Also supporting the original AA/ANA line differences, a trend for lower endogenous corticosterone levels were measured in the high alcohol consumption group compared with the low consumption group. The alcohol challenge test after the drinking period resulted in a higher frequency (38%) of testosterone elevations in the high drinkers compared with the low drinkers (5%). The present data confirms the validity of the positive connections between testosterone elevation and increased alcohol drinking, as well as between testosterone reduction and decreased alcohol drinking, in AA and ANA rats.

  12. Evaluation of AaDOP2 Receptor Antagonists Reveals Antidepressants and Antipsychotics as Novel Lead Molecules for Control of the Yellow Fever Mosquito, Aedes aegypti

    PubMed Central

    Conley, Jason M.; Meyer, Jason M.; Nuss, Andrew B.; Doyle, Trevor B.; Savinov, Sergey N.; Hill, Catherine A.

    2015-01-01

    The yellow fever mosquito, Aedes aegypti, vectors disease-causing agents that adversely affect human health, most notably the viruses causing dengue and yellow fever. The efficacy of current mosquito control programs is challenged by the emergence of insecticide-resistant mosquito populations, suggesting an urgent need for the development of chemical insecticides with new mechanisms of action. One recently identified potential insecticide target is the A. aegypti D1-like dopamine receptor, AaDOP2. The focus of the present study was to evaluate AaDOP2 antagonism both in vitro and in vivo using assay technologies with increased throughput. The in vitro assays revealed AaDOP2 antagonism by four distinct chemical scaffolds from tricyclic antidepressant or antipsychotic chemical classes, and elucidated several structure-activity relationship trends that contributed to enhanced antagonist potency, including lipophilicity, halide substitution on the tricyclic core, and conformational rigidity. Six compounds displayed previously unparalleled potency for in vitro AaDOP2 antagonism, and among these, asenapine, methiothepin, and cis-(Z)-flupenthixol displayed subnanomolar IC50 values and caused rapid toxicity to A. aegypti larvae and/or adults in vivo. Our study revealed a significant correlation between in vitro potency for AaDOP2 antagonism and in vivo toxicity, suggesting viability of AaDOP2 as an insecticidal target. Taken together, this study expanded the repertoire of known AaDOP2 antagonists, enhanced our understanding of AaDOP2 pharmacology, provided further support for rational targeting of AaDOP2, and demonstrated the utility of efficiency-enhancing in vitro and in vivo assay technologies within our genome-to-lead pipeline for the discovery of next-generation insecticides. PMID:25332454

  13. Evidence of the importance of the Met115 for Bacillus thuringiensis subsp. israelensis Cyt1Aa protein cytolytic activity in Escherichia coli.

    PubMed

    Zghal, Raida Zribi; Trigui, Hana; Ben Ali, Mamdouh; Jaoua, Samir

    2008-02-01

    Cyt1Aa is a cytolytic toxin, found together with the delta-endotoxins in Bacillus thuringiensis subsp. israelensis parasporal insecticidal crystals. The latter are used as an environmental friendly insecticide against mosquitoes and black flies. Contrary to Cry delta-endotoxin, the mode of action of Cyt1Aa is not completely understood. In the absence of direct structural data, a novel mutated cyt1Aa gene was used to obtain indirect informations on Cyt1Aa conformation changes in the lipid membrane environment. A mutated cyt1Aa gene named cyt1A97 has been isolated from a B. thuringiensis israelensis strain named BUPM97. The nucleotide sequence predicted a protein of 249 amino acids residues with a calculated molecular mass of 27 kDa. Both nucleotide and amino acid sequences similarity analysis revealed that cyt1A97 presents one amino acid different from the native cyt1Aa gene. This mutation was located in the helix alpha C corresponding to a substitution of Met(115) by a Thr. The heterologous expression of the cyt1A97 and another cyt1Aa-type gene called cyt1A98, not affected by such mutation used as control, was performed in Escherichia coli. It revealed that the mutated Cyt1A97 protein was over produced as inclusion bodies showing a very weak toxicity to E. coli contrarily to Cyt1A98 that stopped E. coli growth. Hence, hydrophobic residue Met at position 115 of Cyt1Aa should play a very important role for the maintenance of the structure and cytolytic functions of Cyt1Aa.

  14. The Effects of Mechanical Properties on Fatigue Behavior of ECAPed AA7075

    NASA Astrophysics Data System (ADS)

    Kaya, Hasan; Uçar, Mehmet

    2016-03-01

    In this study, the effects of equal channel angular pressing (ECAP) on high-cycle fatigue and fatigue surface morphology of AA7075 have been investigated at a constant temperature (483 K) and the "C" route for four passes at ECAP process. ECAPed and as-received specimens were tested by four-point bending fatigue device. Fatigue tests were carried out by using 100, 120 and 140 MPa strength values. ECAPed specimens were characterized for each pass with optical microscope (OM), scanning electron microscope (SEM), energy-dispersive spectroscope (EDS), transmission electron microscope (TEM), selected area electron diffraction (SAED) and hardness measurements. Fracture surfaces of the specimens were also characterized with SEM. The results show that the highest hardness values (137 HV) and the best fatigue life (5.4 × 107 for 100 MPa) were measured in ECAPed four-pass sample. For this reason hardness values and fatigue life were increased with increasing number of severe plastic deformation (SPD) process.

  15. Round-trip mission requirements for Asteroids 1976 AA and 1973 EC

    NASA Technical Reports Server (NTRS)

    Niehoff, J. C.

    1977-01-01

    The feasibility of manned or unmanned missions to two recently discovered asteroids is assessed. Characteristics of a likely target for a round-trip exploratory excursion include: a period close to one year; and an orbit that is nearly circular and nearly coplanar with the ecliptic. Mass requirements and optimal times of launch are investigated for unmanned and manned missions to Asteroids 1976 AA and 1973 EC (recently numbered 1943); 365-day round-trip trajectories in the first half of the 1990s are proposed. However, since neither of the two targets considered entirely fulfills all the necessary orbital characteristics, neither can offer the opportunity for a fast low-energy round-trip mission; nevertheless, other minor planets crossing earth's orbit may be found to meet the requirements.

  16. Chirality-induced magnon transport in AA-stacked bilayer honeycomb chiral magnets

    NASA Astrophysics Data System (ADS)

    Owerre, S. A.

    2016-11-01

    In this Letter, we study the magnetic transport in AA-stacked bilayer honeycomb chiral magnets coupled either ferromagnetically or antiferromagnetically. For both couplings, we observe chirality-induced gaps, chiral protected edge states, magnon Hall and magnon spin Nernst effects of magnetic spin excitations. For ferromagnetically coupled layers, thermal Hall and spin Nernst conductivities do not change sign as function of magnetic field or temperature similar to single-layer honeycomb ferromagnetic insulator. In contrast, for antiferromagnetically coupled layers, we observe a sign change in the thermal Hall and spin Nernst conductivities as the magnetic field is reversed. We discuss possible experimental accessible honeycomb bilayer quantum materials in which these effects can be observed.

  17. Analysis of Surface Roughening in AA6111 Automotive Sheet Under Pure Bending

    NASA Astrophysics Data System (ADS)

    Shi, Y.; Zhao, P. Z.; Jin, H.; Wu, P. D.; Lloyd, D. J.

    2016-02-01

    The finite element method is used to numerically simulate the topographic development in an aluminum sheet, AA6111, under pure bending. The measured electron backscatter diffraction data are directly incorporated into the finite element model, and the constitutive response at an integration point is described by the single crystal plasticity theory. The effects of strain-rate sensitivity, work hardening, and imposed initial surface roughness on surface roughening are studied. It is found that the grains in top surface layers of the sheet play a big role in controlling the outer surface roughness due to the strain gradient across sheet thickness in bending, while the grain size and texture of the surface layers have a direct impact on finishing surface qualities.

  18. Sol-gel hybrid films based on organosilane and montmorillonite for corrosion inhibition of AA2024.

    PubMed

    Dalmoro, V; dos Santos, J H Z; Armelin, E; Alemán, C; Azambuja, D S

    2014-07-15

    The present work reports the production of films on AA2024-T3 composed of vinyltrimethoxysilane (VTMS)/tetraethylorthosilicate (TEOS) with incorporation of montmorillonite (sodium montmorillonite and montmorillonite modified with quaternary ammonium salt, abbreviated Na and 30B, respectively), generated by the sol-gel process. According to FT-IR analyses the incorporation of montmorillonite does not affect silica network. Electrochemical characterization was performed by electrochemical impedance spectroscopy measurement in 0.05 mol L(-1) NaCl solution. Results indicate that montmorillonite incorporation improves the corrosion protection compared to the non-modified system. Scanning electron microscopy micrographs reveal that high concentrations of montmorillonite provide agglomerations on the metallic surface, which is in detriment of the anticorrosive performance. The VTMS/TEOS/30B films with the lowest concentration (22 mg L(-1)) of embedded clay provide the highest corrosion protection.

  19. Experimental Investigation of Turning Parameters on AA 6061-T6 Material

    NASA Astrophysics Data System (ADS)

    Parthiban, A.; Pugazhenthi, R.; Ravikumar, R.; Vivek, P.

    2017-03-01

    Turning is a broadly used material removal process to manufacture cylindrical products. The effects of various process parameters on turning like spindle speed, feed rate and depth of cut have been investigated to Impact on Material Removal Rate (MRR) and surface roughness (Ra) by using Response Surface Methodology. Experimental plan is performed by a Box-behenken design. The main purpose of this work is to study the effect of process parameters on Aluminium alloy AA6061-T6 surface, and to develop the mathematical model for Material removal rate and surface roughness on milling process. The quadratic model is best agreement with experimental data; finally the numerical optimization technique has been used to find out best optimum milling parameters. The optimal set of process parameters has also been predicted to maximize the MRR and minimize the surface roughness.

  20. Assessment of Elemental Content in Airborne Particulate Matter in Bratislava Atmosphere using INAA and AAS

    SciTech Connect

    Meresova, J.; Florek, M.; Holy, K.; Sykora, I.; Frontasyeva, M. V.; Pavlov, S. S.

    2007-11-26

    The wide range concentration of elements including heavy metals, halogens and rare earths in airborne particulate matter were investigated. Sixteen samples were collected on filters in Meteorological station, Comenius University Bratislava (Slovak Republic) in different seasons. Using instrumental neutron activation analysis (INAA) the concentrations of 29 elements (Na, Al, Cl, K, Ca, Sc, Ti, V, Mn, Fe, Ga, As, Se, Br, Rb, In, Sb, I, Cs, Ba, La, Sm, Dy, Tm, W, Au, Hg, Th, U) were determined. The concentrations of other 6 elements (Cr, Ni, Cu, Zn, Cd, Pb) were measured by atomic absorption spectrometry (AAS). The obtained results allow us to better understand the dynamic processes in the atmosphere and to quantify the air pollution and its trends.

  1. Determination of metals in used lubricating oils by AAS using emulsified samples.

    PubMed

    Goncalves, I M; Murillo, M; González, A M

    1998-11-01

    An efficient method was developed for the determination of metals in used lubricating oils, by atomic absorption spectrometry. Oil samples were treated with an acid mixture and then emulsified in water (10% w/w) using ethoxy nonylphenol (6% w/w) as surfactant. Emulsion characteristics (oil, surfactant content and acid mixture) were optimized to obtain the best AAS signal. Good agreement was found between calibration curves of aqueous and emulsified standard solutions when a peristaltic pump was used to introduce the solutions into the flame. The emulsion methodology was comparable, within 95% of confidence, to traditional ashing methodologies when a standard reference oil and a used lubricating oil were analyzed. Precision between 0.4 and 5% RSD was obtained when real sample was analyzed using emulsions.

  2. Microstructure and anisotropic mechanical behavior of friction stir welded AA2024 alloy sheets

    SciTech Connect

    Zhang, Zhihan; Li, Wenya; Li, Jinglong; Chao, Y.J.; Vairis, A.

    2015-09-15

    The anisotropic mechanical properties of friction stir welded (FSW) AA2024-T3 alloy joints were investigated based on the uniaxial tensile tests. The joint microstructure was examined by using electron back-scattered diffraction and transmission electron microscope. Results show that the evident anisotropic failure and yielding are present in the FSW joints. With the increase of loading angle from 0° to 90° the ultimate tensile strength and elongation of the specimens consistently decrease, or at first decrease and then increase, depending on the FSW process parameters. The specimen cut from the weld direction, i.e. a loading angle of 0°, exhibits the highest strength and elongation. - Highlights: • Microstructure and anisotropy of friction stir welded joints were studied. • The evident anisotropic failure and yielding are present in joints. • The lowest yield stress and UTS are at 45° and 60° loadings, respectively. • Rotation speed heavily impact on the anisotropy of joints.

  3. Integral Hot Gas Pressure Forming of an AA2219 Aluminum Alloy Ellipsoidal Shell

    NASA Astrophysics Data System (ADS)

    Yuan, S. J.; Zhang, R.; Zhang, W. W.

    2017-02-01

    To overcome the poor plastic deformation performance of AA2219 aluminum alloy sheet and its weld seam at room temperature, an integral hot gas pressure forming (IHGPF) process for a combined welded ellipsoidal shell was proposed. A simulation of the IHGPF process was conducted to analyze the axis length variation and thickness distribution during the forming process of the combined welded ellipsoidal shell at elevated temperature. The results demonstrated that lengths of the short and long axes were 150 mm and 220 mm, respectively, and that maximum wall thinning occurred at the pole. Furthermore, an experiment was conducted using IHGPF, and the forming accuracy was measured by three-dimensional video technology. A sound ellipsoidal shell with final axis length ratio of 1.5 was obtained with a shell diameter accuracy of more than 99.3%. It was experimentally proven that an aluminum alloy ellipsoidal shell can be formed using the proposed IHGPF technology.

  4. AA stacking, tribological and electronic properties of double-layer graphene with krypton spacer.

    PubMed

    Popov, Andrey M; Lebedeva, Irina V; Knizhnik, Andrey A; Lozovik, Yurii E; Potapkin, Boris V; Poklonski, Nikolai A; Siahlo, Andrei I; Vyrko, Sergey A

    2013-10-21

    Structural, energetic, and tribological characteristics of double-layer graphene with commensurate and incommensurate krypton spacers of nearly monolayer coverage are studied within the van der Waals-corrected density functional theory. It is shown that when the spacer is in the commensurate phase, the graphene layers have the AA stacking. For this phase, the barriers to relative in-plane translational and rotational motion and the shear mode frequency of the graphene layers are calculated. For the incommensurate phase, both of the barriers are found to be negligibly small. A considerable change of tunneling conductance between the graphene layers separated by the commensurate krypton spacer at their relative subangstrom displacement is revealed by the use of the Bardeen method. The possibility of nanoelectromechanical systems based on the studied tribological and electronic properties of the considered heterostructures is discussed.

  5. Billiard simulation and FFT analysis of AAS oscillations in nanofabricated InGaAs

    NASA Astrophysics Data System (ADS)

    Koga, Takaaki; Faniel, Sebastien; Mineshige, Shunsuke; Matsuura, Toru; Sekine, Yoshiaki

    2010-03-01

    Gate-voltage-dependent amplitude of magneto-conductance oscillation was analyzed using FFT method. The obtained FFT spectrum was compared with the areal dependence of the occurrence and spin interferece amplitude, calculated for Altshuler-Aronov-Spivak (AAS) type time-reversal pairs of the interference paths on all possible classical trajectroies that were obtained by extensive billiard simulations within the given structures. We have calcuated generic spin interference (SI) curves as a function of the Rashba parameter α, for various values of the Dresselhaus parameter b41^6c6c [eVå^3]. The comparison between theory and experiment suggested that the value of b41^6c6c should be considerably reduced from 27 eVå^3, the generally known value from the k.p theory.

  6. cAMP/PKA Pathways and S56 Phosphorylation Are Involved in AA/PGE2-Induced Increases in rNaV1.4 Current

    PubMed Central

    Gu, Hua; Fang, Yan-Jia; Liu, Dong-Dong; Chen, Ping; Mei, Yan-Ai

    2015-01-01

    Arachidonic acid (AA) and its metabolites are important second messengers for ion channel modulation. The effects of extracellular application of AA and its non-metabolized analogue on muscle rNaV1.4 Na+ current has been studied, but little is known about the effects of intracellular application of AA on this channel isoform. Here, we report that intracellular application of AA significantly augmented the rNaV1.4 current peak without modulating the steady-state activation and inactivation properties of the rNaV1.4 channel. These results differed from the effects of extracellular application of AA on rNaV1.4 current. The effects of intracellular AA were mimicked by prostaglandin E2 but not eicosatetraynoic acid (ETYA), the non-metabolized analogue of AA, and were eliminated by treatment with cyclooxygenase inhibitors, flufenamic acid, or indomethacin. AA/PGE2-induced activation of rNaV1.4 channels was mimicked by a cAMP analogue (db-cAMP) and eliminated by a PKA inhibitor, PKAi. Furthermore, inhibition of EP2 and EP4 (PGE2 receptors) with AH6809 and AH23848 reduced the intracellular AA/PGE2-induced increase of rNaV1.4 current. Two mutated channels, rNaV1.4S56A and rNaV1.4T21A, were designed to investigate the role of predicted phosphorylation sites in the AA/PGE2–mediated regulation of rNaV1.4 currents. In rNaV1.4S56A, the effects of intracellular db-cAMP, AA, and PGE2 were significantly reduced. The results of the present study suggest that intracellular AA augments rNaV1.4 current by PGE2/EP receptor-mediated activation of the cAMP/PKA pathway, and that the S56 residue on the channel protein is important for this process. PMID:26485043

  7. Insecticidal activity of Vip3Aa, Vip3Ad, Vip3Ae, and Vip3Af from Bacillus thuringiensis against lepidopteran corn pests.

    PubMed

    Hernández-Martínez, Patricia; Hernández-Rodríguez, Carmen Sara; Rie, Jeroen Van; Escriche, Baltasar; Ferré, Juan

    2013-05-01

    Vip3Aa, Vip3Ad, Vip3Ae, and Vip3Af proteins from Bacillus thuringiensis were tested for their toxicity against Spodoptera frugiperda and Agrotis ipsilon. Vip3Ad was non-toxic to the two species. Vip3Ae and Vip3Af were significantly more toxic than Vip3Aa against S. frugiperda, both as protoxins and as toxins. Against A. ipsilon, Vip3Ae protoxin was more toxic than Vip3Aa and Vip3Af protoxins. Purification by metal-chelate affinity chromatography significantly affected Vip3Ae toxicity against the two insect species.

  8. Revealing obliterated engraved marks on high strength aluminium alloy (AA7010) surfaces by etching technique.

    PubMed

    Bong, Yeu Uei; Kuppuswamy, R

    2010-02-25

    Restoration of obliterated engraved marks on high strength Al-Zn-Mg-Cu alloy (AA7010) surfaces by etching technique was studied. The alloy surfaces were mechanically engraved with some identification marks using "Gravograph". The marks were then erased by removing the metal to different levels up to and below the depth of engraving. Five metallographic reagents were tested on the obliterated surfaces by etching. The following two methods (i) immersion in 10% aq. phosphoric acid and (ii) alternate swabbing of 60% HCl and 40% NaOH were found to be quite effective to reveal the obliterated marks. These two procedures were also able to show effectively the marks obliterated by over-engraving and centre punching. Of the two techniques immersion in phosphoric acid provided more contrast. Interestingly, alternate swabbing of 60% HCl and 40% NaOH presented itself to be the common reagent for restoration on pure aluminium as well as its alloy surfaces. This is evident from our own current experiments and those of earlier researchers [G. Peeler, S. Gutowski, H. Wrobel, G. Dower, The restoration of impressed characters on aluminium alloy motor cycle frames, J. Forensic Ident. 58 (1) (2008) 27-32; M. Izhar M. Baharum, R. Kuppuswamy, A.A. Rahman, Restoration of engraved marks on aluminium surfaces by etching technique, Forensic Sci. Int. 177 (2008) 221-227]. The findings have assumed importance as engines and chassis of cars and frames of firearms are currently made of high strength aluminium alloys and recovery on these surfaces by current methods is not satisfactory.

  9. Imaging the Disk and Jet of the Classical T Tauri Star AA Tau

    NASA Technical Reports Server (NTRS)

    Cox, Andrew W.; Grady, Carol A.; Hammel, Heidi B.; Hornbeck, Jeremy; Russell, Ray W.; Sitko, Michael L.; Woodgate, Bruce E.

    2013-01-01

    Previous studies of the classical T Tauri star AA Tau have interpreted the UX-Orionis-like photo-polarimetric variability as being due to a warp in the inner disk caused by an inclined stellar magnetic dipole field. We test that these effects are macroscopically observable in the inclination and alignment of the disk. We use Hubble Space Telescope (HST)/STIS coronagraphic imagery to measure the V magnitude of the star for both STIS coronagraphic observations, compare these data with optical photometry in the literature, and find that, unlike other classical T Tauri stars observed in the same HST program, the disk is most robustly detected in scattered light at stellar optical minimum light.We measure the outer disk radius, 1 inch.15 plus-minus 0 inch.10, major-axis position angle, and disk inclination and find that the inner disk, as reported in the literature, is both misinclined and misaligned with respect to the outer disk. AA Tau drives a faint jet, detected in both STIS observations and in follow-on Goddard Fabry-Perot imagery, which is also misaligned with respect to the projection of the outer disk minor axis and is poorly collimated near the star, but which can be traced 21 inches from the star in data from 2005. The measured outer disk inclination, 71deg plus-minus 1deg, is out of the range of inclinations suggested for stars with UX-Orionis-like variability when no grain growth has occurred in the disk. The faintness of the disk, small disk size, and detection of the star despite the high inclination all indicate that the dust disk must have experienced grain growth and settling toward the disk midplane, which we verify by comparing the observed disk with model imagery from the literature.

  10. The Effect of Newly Developed OPLS-AA Alanyl Radical Parameters on Peptide Secondary Structure.

    PubMed

    Owen, Michael C; Tóth, László; Jojárt, Balázs; Komáromi, István; Csizmadia, Imre G; Viskolcz, Bela

    2012-08-14

    Recent studies using ab initio calculations have shown that Cα-centered radical formation by H-abstraction from the backbone of peptide residues has dramatic effects on peptide structure and have suggested that this reaction may contribute to the protein misfolding observed in Alzheimer's and Parkinson's diseases. To enable the effects of Cα-centered radicals to be studied in longer peptides and proteins over longer time intervals, force-field parameters for the Cα-centered Ala radical were developed for use with the OPLS force field by minimizing the sum of squares deviation between the quantum chemical and OPLS-AA energy hypersurfaces. These parameters were used to determine the effect of the Cα-centered Ala radical on the structure of a hepta-alanyl peptide in molecular dynamics (MD) simulations. A negligible sum-of-squares energy deviation was observed in the stretching parameters, and the newly developed OPLS-AA torsional parameters showed a good agreement with the LMP2/cc-pVTZ(-f) hypersurface. The parametrization also demonstrated that derived force-field bond length and bond angle parameters can deviate from the quantum chemical equilibrium values, and that the improper torsional parameters should be developed explicitly with respect to the coupled torsional parameters. The MD simulations showed planar conformations of the Cα-containing residue (Alr) are preferred and these conformations increase the formation of γ-, α-, and π-turn structures depending on the position in the turn occupied by the Alr residue. Higher-ordered structures are destabilized by Alr except when this residue occupies position "i + 1" of the 310-helix. These results offer new insight into the protein-misfolding mechanisms initiated by H-abstraction from the Cα of peptide and protein residues.

  11. Molecular Differences in Hepatic Metabolism between AA Broiler and Big Bone Chickens: A Proteomic Study

    PubMed Central

    Liu, Guohua; Yue, Ying; Li, Jianke; Zhang, Shu; Cai, Huiyi; Yang, Aijun; Chen, Zhimin

    2016-01-01

    Identifying the metabolic differences in the livers of modern broilers and local chicken breeds is important for understanding their biological characteristics, and many proteomic changes in their livers are not well characterized. We therefore analyzed the hepatic protein profiles of a commercial breed, Arbor Acres (AA) broilers, and a local dual purpose breed, Big Bone chickens, using two-dimensional electrophoresis combined with liquid chromatography-chip/electrospray ionization-quadruple time-of-flight/mass spectrometry (LC-MS/MS). A total of 145 proteins were identified as having differential abundance in the two breeds at three growth stages. Among them, 49, 63 and 54 belonged to 2, 4, and 6 weeks of age, respectively. The higher abundance proteins in AA broilers were related to the energy production pathways suggesting enhanced energy metabolism and lipid biosynthesis. In contrast, the higher abundance proteins in Big Bone chickens showed enhanced lipid degradation, resulting in a reduction in the abdominal fat percentage. Along with the decrease in fat deposition, flavor substance synthesis in the meat of the Big Bone chickens may be improved by enhanced abundance of proteins involved in glycine metabolism. In addition, the identified proteins in nucleotide metabolism, antioxidants, cell structure, protein folding and transporters may be critically important for immune defense, gene transcription and other biological processes in the two breeds. These results indicate that selection pressure may have shaped the two lines differently resulting in different hepatic metabolic capacities and extensive metabolic differences in the liver. The results from this study may help provide the theoretical basis for chicken breeding. PMID:27760160

  12. Estimate of the uncertainty in measurement for the determination of mercury in seafood by TDA AAS.

    PubMed

    Torres, Daiane Placido; Olivares, Igor R B; Queiroz, Helena Müller

    2015-01-01

    An approach for the estimate of the uncertainty in measurement considering the individual sources related to the different steps of the method under evaluation as well as the uncertainties estimated from the validation data for the determination of mercury in seafood by using thermal decomposition/amalgamation atomic absorption spectrometry (TDA AAS) is proposed. The considered method has been fully optimized and validated in an official laboratory of the Ministry of Agriculture, Livestock and Food Supply of Brazil, in order to comply with national and international food regulations and quality assurance. The referred method has been accredited under the ISO/IEC 17025 norm since 2010. The approach of the present work in order to reach the aim of estimating of the uncertainty in measurement was based on six sources of uncertainty for mercury determination in seafood by TDA AAS, following the validation process, which were: Linear least square regression, Repeatability, Intermediate precision, Correction factor of the analytical curve, Sample mass, and Standard reference solution. Those that most influenced the uncertainty in measurement were sample weight, repeatability, intermediate precision and calibration curve. The obtained result for the estimate of uncertainty in measurement in the present work reached a value of 13.39%, which complies with the European Regulation EC 836/2011. This figure represents a very realistic estimate of the routine conditions, since it fairly encompasses the dispersion obtained from the value attributed to the sample and the value measured by the laboratory analysts. From this outcome, it is possible to infer that the validation data (based on calibration curve, recovery and precision), together with the variation on sample mass, can offer a proper estimate of uncertainty in measurement.

  13. IMAGING THE DISK AND JET OF THE CLASSICAL T TAURI STAR AA TAU

    SciTech Connect

    Cox, Andrew W.; Grady, Carol A.; Hammel, Heidi B.; Hornbeck, Jeremy; Russell, Ray W.; Sitko, Michael L.; Woodgate, Bruce E.

    2013-01-01

    Previous studies of the classical T Tauri star AA Tau have interpreted the UX-Orionis-like photo-polarimetric variability as being due to a warp in the inner disk caused by an inclined stellar magnetic dipole field. We test that these effects are macroscopically observable in the inclination and alignment of the disk. We use Hubble Space Telescope (HST)/STIS coronagraphic imagery to measure the V magnitude of the star for both STIS coronagraphic observations, compare these data with optical photometry in the literature, and find that, unlike other classical T Tauri stars observed in the same HST program, the disk is most robustly detected in scattered light at stellar optical minimum light. We measure the outer disk radius, 1.''15 {+-} 0.''10, major-axis position angle, and disk inclination and find that the inner disk, as reported in the literature, is both misinclined and misaligned with respect to the outer disk. AA Tau drives a faint jet, detected in both STIS observations and in follow-on Goddard Fabry-Perot imagery, which is also misaligned with respect to the projection of the outer disk minor axis and is poorly collimated near the star, but which can be traced 21'' from the star in data from 2005. The measured outer disk inclination, 71 Degree-Sign {+-} 1 Degree-Sign , is out of the range of inclinations suggested for stars with UX-Orionis-like variability when no grain growth has occurred in the disk. The faintness of the disk, small disk size, and detection of the star despite the high inclination all indicate that the dust disk must have experienced grain growth and settling toward the disk midplane, which we verify by comparing the observed disk with model imagery from the literature.

  14. Imaging the Disk and Jet of the Classical T Tauri Star AA Tau

    NASA Astrophysics Data System (ADS)

    Cox, Andrew; Grady, C.; Hammel, H. B.; Hornbeck, J.; Russell, R. W.; Sitko, M. L.; Woodgate, B. E.

    2013-01-01

    Previous studies of the classical T Tauri star AA Tau have interpreted the UX Orionis-like photo-polarimetric variability as being due to a warp in the inner disk caused by an inclined stellar magnetic dipole field. We test that these effects are macroscopically observable in the inclination and alignment of the disk. We use HST/STIS coronagraphic imagery to measure the V magnitude of the star for both STIS corona graphic observations, compare these data with optical photometry in the literature and find that unlike other classical T Tauri stars observed on the same HST program, the disk is most robustly detected at optical minimum light. We measure the outer disk radius, major axis position angle, and disk inclination, and find that the inner disk, as reported in the literature, is both mis-inclined and misaligned with respect to the outer disk. AA Tau drives a faint jet which is also misaligned with respect to the projection of the outer disk minor axis and which is poorly collimated near the star. The measured outer disk inclination, 71±1 degrees, is out of the inclination band suggested for stars with UX Orionis-like variability where no grain growth has occurred in the disk. The faintness of the disk, the small disk size, and visibility of the star and despite the high inclination, all indicate that the disk must have experienced grain growth and settling toward the disk midplane, which we verify by comparing the observed disk with model imagery from the literature.

  15. Imaging the Disk and Jet of the Classical T Tauri Star AA Tau

    NASA Astrophysics Data System (ADS)

    Cox, Andrew W.; Grady, Carol A.; Hammel, Heidi B.; Hornbeck, Jeremy; Russell, Ray W.; Sitko, Michael L.; Woodgate, Bruce E.

    2013-01-01

    Previous studies of the classical T Tauri star AA Tau have interpreted the UX-Orionis-like photo-polarimetric variability as being due to a warp in the inner disk caused by an inclined stellar magnetic dipole field. We test that these effects are macroscopically observable in the inclination and alignment of the disk. We use Hubble Space Telescope (HST)/STIS coronagraphic imagery to measure the V magnitude of the star for both STIS coronagraphic observations, compare these data with optical photometry in the literature, and find that, unlike other classical T Tauri stars observed in the same HST program, the disk is most robustly detected in scattered light at stellar optical minimum light. We measure the outer disk radius, 1.''15 ± 0.''10, major-axis position angle, and disk inclination and find that the inner disk, as reported in the literature, is both misinclined and misaligned with respect to the outer disk. AA Tau drives a faint jet, detected in both STIS observations and in follow-on Goddard Fabry-Perot imagery, which is also misaligned with respect to the projection of the outer disk minor axis and is poorly collimated near the star, but which can be traced 21'' from the star in data from 2005. The measured outer disk inclination, 71° ± 1°, is out of the range of inclinations suggested for stars with UX-Orionis-like variability when no grain growth has occurred in the disk. The faintness of the disk, small disk size, and detection of the star despite the high inclination all indicate that the dust disk must have experienced grain growth and settling toward the disk midplane, which we verify by comparing the observed disk with model imagery from the literature.

  16. Molecular Differences in Hepatic Metabolism between AA Broiler and Big Bone Chickens: A Proteomic Study.

    PubMed

    Zheng, Aijuan; Chang, Wenhuan; Liu, Guohua; Yue, Ying; Li, Jianke; Zhang, Shu; Cai, Huiyi; Yang, Aijun; Chen, Zhimin

    2016-01-01

    Identifying the metabolic differences in the livers of modern broilers and local chicken breeds is important for understanding their biological characteristics, and many proteomic changes in their livers are not well characterized. We therefore analyzed the hepatic protein profiles of a commercial breed, Arbor Acres (AA) broilers, and a local dual purpose breed, Big Bone chickens, using two-dimensional electrophoresis combined with liquid chromatography-chip/electrospray ionization-quadruple time-of-flight/mass spectrometry (LC-MS/MS). A total of 145 proteins were identified as having differential abundance in the two breeds at three growth stages. Among them, 49, 63 and 54 belonged to 2, 4, and 6 weeks of age, respectively. The higher abundance proteins in AA broilers were related to the energy production pathways suggesting enhanced energy metabolism and lipid biosynthesis. In contrast, the higher abundance proteins in Big Bone chickens showed enhanced lipid degradation, resulting in a reduction in the abdominal fat percentage. Along with the decrease in fat deposition, flavor substance synthesis in the meat of the Big Bone chickens may be improved by enhanced abundance of proteins involved in glycine metabolism. In addition, the identified proteins in nucleotide metabolism, antioxidants, cell structure, protein folding and transporters may be critically important for immune defense, gene transcription and other biological processes in the two breeds. These results indicate that selection pressure may have shaped the two lines differently resulting in different hepatic metabolic capacities and extensive metabolic differences in the liver. The results from this study may help provide the theoretical basis for chicken breeding.

  17. Synergism between cerium nitrate and sodium dodecylbenzenesulfonate on corrosion of AA5052 aluminium alloy in 3 wt.% NaCl solution

    NASA Astrophysics Data System (ADS)

    Liu, Jie; Wang, Dapeng; Gao, Lixin; Zhang, Daquan

    2016-12-01

    The synergistic inhibition effect of rare earth cerium nitrate and sodium dodecylbenzenesulfonate (DBS) on corrosion of AA5052 aluminium alloy in 3 wt.% NaCl solution was investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curve, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR). The results show that the single cerium nitrate or DBS has a limited inhibition effect against corrosion of AA5052 alloy. The combination cerium ions with DBS produced strong synergistic effect on corrosion inhibition for AA5052 alloy and rendered a negaitve shift of the corrosion potential. The formation of the complex of Al(DBS)3 and Ce(DBS)3 stabilized the passive film of Al2O3 and CeO2, retarding both the cathodic and anodic processes of AA5052 alloy corrosion reaction significantly.

  18. Bacillus thuringiensis insecticidal Cry1Aa toxin binds to a highly conserved region of aminopeptidase N in the host insect leading to its evolutionary success.

    PubMed

    Nakanishi, K; Yaoi, K; Shimada, N; Kadotani, T; Sato, R

    1999-06-15

    Bacillus thuringiensis insecticidal protein, Cry1Aa toxin, binds to a specific receptor in insect midguts and has insecticidal activity. Therefore, the structure of the receptor molecule is probably a key factor in determining the binding affinity of the toxin and insect susceptibility. The cDNA fragment (PX frg1) encoding the Cry1Aa toxin-binding region of an aminopeptidase N (APN) or an APN family protein from diamondback moth, Plutella xylostella midgut was cloned and sequenced. A comparison between the deduced amino acid sequence of PX frg1 and other insect APN sequences shows that Cry1Aa toxin binds to a highly conserved region of APN family protein. In this paper, we propose a model to explain the mechanism that causes B. thuringiensis evolutionary success and differing insect susceptibility to Cry1Aa toxin.

  19. Study of the Bacillus thuringiensis Vip3Aa16 histopathological effects and determination of its putative binding proteins in the midgut of Spodoptera littoralis.

    PubMed

    Abdelkefi-Mesrati, Lobna; Boukedi, Hanen; Dammak-Karray, Mariam; Sellami-Boudawara, Tahya; Jaoua, Samir; Tounsi, Slim

    2011-02-01

    The bacterium Bacillus thuringiensis produces, at the vegetative stage of its growth, Vip3A proteins with activity against a broad spectrum of lepidopteran insects. The Egyptian cotton leaf worm (Spodoptera littoralis) is an important agricultural pest that is susceptible to the Vip3Aa16 protein of Bacillus thuringiensis kurstaki strain BUPM95. The midgut histopathology of Vip3Aa fed larvae showed vacuolization of the cytoplasm, brush border membrane destruction, vesicle formation in the apical region and cellular disintegration. Biotinylated Vip3Aa toxin bound proteins of 55- and 100-kDa on blots of S. littoralis brush border membrane preparations. These binding proteins differ in molecular size from those recognized by Cry1C, one of the very few Cry proteins active against the polyphagous S. littoralis. This result supports the use of Vip3Aa16 proteins as insecticidal agent, especially in case of Cry-resistance management.

  20. Ciliary transport regulates PDGF-AA/αα signaling via elevated mammalian target of rapamycin signaling and diminished PP2A activity.

    PubMed

    Umberger, Nicole L; Caspary, Tamara

    2015-01-15

    Primary cilia are built and maintained by intraflagellar transport (IFT), whereby the two IFT complexes, IFTA and IFTB, carry cargo via kinesin and dynein motors for anterograde and retrograde transport, respectively. Many signaling pathways, including platelet- derived growth factor (PDGF)-AA/αα, are linked to primary cilia. Active PDGF-AA/αα signaling results in phosphorylation of Akt at two residues: P-Akt(T308) and P-Akt(S473), and previous work showed decreased P-Akt(S473) in response to PDGF-AA upon anterograde transport disruption. In this study, we investigated PDGF-AA/αα signaling via P-Akt(T308) and P-Akt(S473) in distinct ciliary transport mutants. We found increased Akt phosphorylation in the absence of PDGF-AA stimulation, which we show is due to impaired dephosphorylation resulting from diminished PP2A activity toward P-Akt(T308). Anterograde transport mutants display low platelet-derived growth factor receptor (PDGFR)α levels, whereas retrograde mutants exhibit normal PDGFRα levels. Despite this, neither shows an increase in P-Akt(S473) or P-Akt(T308) upon PDGF-AA stimulation. Because mammalian target of rapamycin complex 1 (mTORC1) signaling is increased in ciliary transport mutant cells and mTOR signaling inhibits PDGFRα levels, we demonstrate that inhibition of mTORC1 rescues PDGFRα levels as well as PDGF-AA-dependent phosphorylation of Akt(S473) and Akt(T308) in ciliary transport mutant MEFs. Taken together, our data indicate that the regulation of mTORC1 signaling and PP2A activity by ciliary transport plays key roles in PDGF-AA/αα signaling.

  1. Carbon Dots and 9AA as a Binary Matrix for the Detection of Small Molecules by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Chen, Yongli; Gao, Dan; Bai, Hangrui; Liu, Hongxia; Lin, Shuo; Jiang, Yuyang

    2016-07-01

    Application of matrix-assisted laser-desorption/ionization mass spectrometry (MALDI MS) to analyze small molecules have some limitations, due to the inhomogeneous analyte/matrix co-crystallization and interference of matrix-related peaks in low m/z region. In this work, carbon dots (CDs) were for the first time applied as a binary matrix with 9-Aminoacridine (9AA) in MALDI MS for small molecules analysis. By 9AA/CDs assisted desorption/ionization (D/I) process, a wide range of small molecules, including nucleosides, amino acids, oligosaccharides, peptides, and anticancer drugs with a higher sensitivity were demonstrated in the positive ion mode. A detection limit down to 5 fmol was achieved for cytidine. 9AA/CDs matrix also exhibited excellent reproducibility compared with 9AA matrix. Moreover, by exploring the ionization mechanism of the matrix, the influence factors might be attributed to the four parts: (1) the strong UV absorption of 9AA/CDs due to their π-conjugated network; (2) the carboxyl groups modified on the CDs surface act as protonation sites for proton transfer in positive ion mode; (3) the thin layer crystal of 9AA/CDs could reach a high surface temperature more easily and lower transfer energy for LDI MS; (4) CDs could serve as a matrix additive to suppress 9AA ionization. Furthermore, this matrix was allowed for the analysis of glucose as well as nucleosides in human urine, and the level of cytidine was quantified with a linear range of 0.05-5 mM (R2 > 0.99). Therefore, the 9AA/CDs matrix was proven to be an effective MALDI matrix for the analysis of small molecules with improved sensitivity and reproducibility. This work provides an alternative solution for small molecules detection that can be further used in complex samples analysis.

  2. Carbon Dots and 9AA as a Binary Matrix for the Detection of Small Molecules by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry.

    PubMed

    Chen, Yongli; Gao, Dan; Bai, Hangrui; Liu, Hongxia; Lin, Shuo; Jiang, Yuyang

    2016-07-01

    Application of matrix-assisted laser-desorption/ionization mass spectrometry (MALDI MS) to analyze small molecules have some limitations, due to the inhomogeneous analyte/matrix co-crystallization and interference of matrix-related peaks in low m/z region. In this work, carbon dots (CDs) were for the first time applied as a binary matrix with 9-Aminoacridine (9AA) in MALDI MS for small molecules analysis. By 9AA/CDs assisted desorption/ionization (D/I) process, a wide range of small molecules, including nucleosides, amino acids, oligosaccharides, peptides, and anticancer drugs with a higher sensitivity were demonstrated in the positive ion mode. A detection limit down to 5 fmol was achieved for cytidine. 9AA/CDs matrix also exhibited excellent reproducibility compared with 9AA matrix. Moreover, by exploring the ionization mechanism of the matrix, the influence factors might be attributed to the four parts: (1) the strong UV absorption of 9AA/CDs due to their π-conjugated network; (2) the carboxyl groups modified on the CDs surface act as protonation sites for proton transfer in positive ion mode; (3) the thin layer crystal of 9AA/CDs could reach a high surface temperature more easily and lower transfer energy for LDI MS; (4) CDs could serve as a matrix additive to suppress 9AA ionization. Furthermore, this matrix was allowed for the analysis of glucose as well as nucleosides in human urine, and the level of cytidine was quantified with a linear range of 0.05-5 mM (R(2) > 0.99). Therefore, the 9AA/CDs matrix was proven to be an effective MALDI matrix for the analysis of small molecules with improved sensitivity and reproducibility. This work provides an alternative solution for small molecules detection that can be further used in complex samples analysis. Graphical Abstract ᅟ.

  3. Effect of adding amino acids residues in N- and C-terminus of Vip3Aa16 (L121I) toxin.

    PubMed

    Sellami, Sameh; Cherif, Marwa; Jamoussi, Kaïs

    2016-06-01

    To study the importance of N- and C-terminus of Bacillus thuringiensis Vip3Aa16 (L121I) toxin (88 kDa), a number of mutants were generated. The addition of two (2R: RS) or eleven (11R: RSRPGHHHHHH) amino acid residues at the Vip3Aa16 (L121I) C-terminus allowed to an unappropriated folding illustrated by the abundant presence of the 62 kDa proteolytic form. The produced Vip3Aa16 (L121I) full length form was less detected when increasing the number of amino acids residues in the C-terminus. Bioassays demonstrated that the growth of the lepidopteran Ephestia kuehniella was slightly affected by Vip3Aa16 (L121I)-2R and not affected by Vip3Aa16 (L121I)-11R. Additionally, the fusion at the Vip3Aa16 (L121I) N-terminus of 39 amino acids harboring the E. coli OmpA leader peptide and the His-tag sequence allowed to the increase of protease sensitivity of Vip3Aa16 (L121I) full length form, as only the 62 kDa proteolysis form was detected. Remarkably, this fused protein produced in Escherichia coli (E. coli) was biologically inactive toward Ephestia kuehniella larvae. Thus, the N-terminus of the protein is required to the accomplishment of the insecticidal activity of Vip3 proteins. This report serves as guideline for the study of Vip3Aa16 (L121I) protein stability and activity.

  4. Adsorption characteristics of anionic nutrients onto the PP-g-AA-Am non-woven fabric prepared by photoinduced graft and subsequent chemical modification.

    PubMed

    Park, Hyun-Ju; Na, Choon-Ki

    2009-07-30

    PP-g-AA-Am non-woven fabric, which possesses anionic exchangeable function, was prepared by chemical modification of carboxyl group in PP-g-AA non-woven fabric to amine group using diethylene triamine. Its sorption characteristics for anionic nutrients including isotherm, kinetics, effects of pH and co-anions, and regeneration efficiency were studied by batch sorption experiments. Sorption equilibriums of PO(4)-P on PP-g-AA-Am fabric were well described by the Langmuir isotherm model, and their sorption energies were ranged between 9.94 and 15.96 kJ/mol indicating an ion exchange process as primary sorption mechanism. Sorption kinetic data fitted with pseudo-second-order kinetic model and indicated that both external and intraparticle diffusion took part in sorption processes. The uptake of PO(4)-P by PP-g-AA-Am fabric increased with increasing pH of solution and its optimum pH region was in pH >or=4, whereas the uptake of NO(3)-N and NO(2)-N was higher in weak and strong acidic pH region, respectively. The sorption selectivity for anions by PP-g-AA-Am fabric was increased in the order: SO(4)>or=PO(4)>NO(3)>Cl. The PP-g-AA-Am fabric could be regenerated by a simple acid washing process without lowering the sorption capacity or physical durability.

  5. Transcriptional profiling analysis of Spodoptera litura larvae challenged with Vip3Aa toxin and possible involvement of trypsin in the toxin activation

    PubMed Central

    Song, Feifei; Chen, Chen; Wu, Songqing; Shao, Ensi; Li, Mengnan; Guan, Xiong; Huang, Zhipeng

    2016-01-01

    Vip proteins, a new group of insecticidal toxins produced by Bacillus thuringiensis, are effective against specific pests including Spodoptera litura. Here, we report construction of a transcriptome database of S. litura by de novo assembly along with detection of the transcriptional response of S. litura larvae to Vip3Aa toxin. In total, 56,498 unigenes with an N50 value of 1,853 bp were obtained. Results of transcriptome abundance showed that Vip3Aa toxin provoked a wide transcriptional response of the S. litura midgut. The differentially expressed genes were enriched for immunity-related, metabolic-related and Bt-related genes. Twenty-nine immunity-related genes, 102 metabolic-related genes and 62 Bt-related genes with differential expression were found. On the basis of transcriptional profiling analysis, we focus on the functional validation of trypsin which potentially participated in the activation of Vip3Aa protoxin. Zymogram analysis indicated that the presence of many proteases, including trypsin, in S. litura larvae midgut. Results of enzymolysis in vitro of Vip3Aa by trypsin, and bioassay and histopathology of the trypsin-digested Vip3Aa toxin showed that trypsin was possibly involved in the Vip3Aa activation. This study provides a transcriptome foundation for the identification and functional validation of the differentially expressed genes in an agricultural important pest, S. litura. PMID:27025647

  6. Binding of the pathogen receptor HSP90AA1 to avibirnavirus VP2 induces autophagy by inactivating the AKT-MTOR pathway.

    PubMed

    Hu, Boli; Zhang, Yina; Jia, Lu; Wu, Huansheng; Fan, Chengfei; Sun, Yanting; Ye, Chengjin; Liao, Min; Zhou, Jiyong

    2015-01-01

    Autophagy is an essential component of host innate and adaptive immunity. Viruses have developed diverse strategies for evading or utilizing autophagy for survival. The response of the autophagy pathways to virus invasion is poorly documented. Here, we report on the induction of autophagy initiated by the pathogen receptor HSP90AA1 (heat shock protein 90 kDa α [cytosolic], class A member 1) via the AKT-MTOR (mechanistic target of rapamycin)-dependent pathway. Transmission electron microscopy and confocal microscopy revealed that intracellular autolysosomes packaged avibirnavirus particles. Autophagy detection showed that early avibirnavirus infection not only increased the amount of light chain 3 (LC3)-II, but also upregulated AKT-MTOR dephosphorylation. HSP90AA1-AKT-MTOR knockdown by RNA interference resulted in inhibition of autophagy during avibirnavirus infection. Virus titer assays further verified that autophagy inhibition, but not induction, enhanced avibirnavirus replication. Subsequently, we found that HSP90AA1 binding to the viral protein VP2 resulted in induction of autophagy and AKT-MTOR pathway inactivation. Collectively, our findings suggest that the cell surface protein HSP90AA1, an avibirnavirus-binding receptor, induces autophagy through the HSP90AA1-AKT-MTOR pathway in early infection. We reveal that upon viral recognition, a direct connection between HSP90AA1 and the AKT-MTOR pathway trigger autophagy, a critical step for controlling infection.

  7. Identification of Bacillus thuringiensis Cry3Aa toxin domain II loop 1 as the binding site of Tenebrio molitor cadherin repeat CR12.

    PubMed

    Zúñiga-Navarrete, Fernando; Gómez, Isabel; Peña, Guadalupe; Amaro, Itzel; Ortíz, Ernesto; Becerril, Baltazar; Ibarra, Jorge E; Bravo, Alejandra; Soberón, Mario

    2015-04-01

    Bacillus thuringiensis Cry toxins exert their toxic effect by specific recognition of larval midgut proteins leading to oligomerization of the toxin, membrane insertion and pore formation. The exposed domain II loop regions of Cry toxins have been shown to be involved in receptor binding. Insect cadherins have shown to be functionally involved in toxin binding facilitating toxin oligomerization. Here, we isolated a VHH (VHHA5) antibody by phage display that binds Cry3Aa loop 1 and competed with the binding of Cry3Aa to Tenebrio molitor brush border membranes. VHHA5 also competed with the binding of Cry3Aa to a cadherin fragment (CR12) that was previously shown to be involved in binding and toxicity of Cry3Aa, indicating that Cry3Aa binds CR12 through domain II loop 1. Moreover, we show that a loop 1 mutant, previously characterized to have increased toxicity to T. molitor, displayed a correlative enhanced binding affinity to T. molitor CR12 and to VHHA5. These results show that Cry3Aa domain II loop 1 is a binding site of CR12 T. molitor cadherin.

  8. The primary transcriptome of the Escherichia coli O104:H4 pAA plasmid and novel insights into its virulence gene expression and regulation

    PubMed Central

    Berger, Petya; Knödler, Michael; Förstner, Konrad U.; Berger, Michael; Bertling, Christian; Sharma, Cynthia M.; Vogel, Jörg; Karch, Helge; Dobrindt, Ulrich; Mellmann, Alexander

    2016-01-01

    Escherichia coli O104:H4 (E. coli O104:H4), which caused a massive outbreak of acute gastroenteritis and hemolytic uremic syndrome in 2011, carries an aggregative adherence fimbriae I (AAF/I) encoding virulence plasmid, pAA. The importance of pAA in host-pathogen interaction and disease severity has been demonstrated, however, not much is known about its transcriptional organization and gene regulation. Here, we analyzed the pAA primary transcriptome using differential RNA sequencing, which allows for the high-throughput mapping of transcription start site (TSS) and non-coding RNA candidates. We identified 248 TSS candidates in the 74-kb pAA and only 21% of them could be assigned as TSS of annotated genes. We detected TSS for the majority of pAA-encoded virulence factors. Interestingly, we mapped TSS, which could allow for the transcriptional uncoupling of the AAF/I operon, and potentially regulatory antisense RNA candidates against the genes encoding dispersin and the serine protease SepA. Moreover, a computational search for transcription factor binding sites suggested for AggR-mediated activation of SepA expression, which was additionally experimentally validated. This work advances our understanding of the molecular basis of E. coli O104:H4 pathogenicity and provides a valuable resource for further characterization of pAA virulence gene regulation. PMID:27748404

  9. Genome of brown tide virus (AaV), the little giant of the Megaviridae, elucidates NCLDV genome expansion and host-virus coevolution.

    PubMed

    Moniruzzaman, Mohammad; LeCleir, Gary R; Brown, Christopher M; Gobler, Christopher J; Bidle, Kay D; Wilson, William H; Wilhelm, Steven W

    2014-10-01

    Aureococcus anophagefferens causes economically and ecologically destructive "brown tides" in the United States, China and South Africa. Here we report the 370,920bp genomic sequence of AaV, a virus capable of infecting and lysing A. anophagefferens. AaV is a member of the nucleocytoplasmic large DNA virus (NCLDV) group, harboring 377 putative coding sequences and 8 tRNAs. Despite being an algal virus, AaV shows no phylogenetic affinity to the Phycodnaviridae family, to which most algae-infecting viruses belong. Core gene phylogenies, shared gene content and genome-wide similarities suggest AaV is the smallest member of the emerging clade "Megaviridae". The genomic architecture of AaV demonstrates that the ancestral virus had an even smaller genome, which expanded through gene duplication and assimilation of genes from diverse sources including the host itself - some of which probably modulate important host processes. AaV also harbors a number of genes exclusive to phycodnaviruses - reinforcing the hypothesis that Phycodna- and Mimiviridae share a common ancestor.

  10. Characterization of the resistance to Vip3Aa in Helicoverpa armigera from Australia and the role of midgut processing and receptor binding

    PubMed Central

    Chakroun, Maissa; Banyuls, Núria; Walsh, Tom; Downes, Sharon; James, Bill; Ferré, Juan

    2016-01-01

    Crops expressing genes from Bacillus thuringiensis (Bt crops) are among the most successful technologies developed for the control of pests but the evolution of resistance to them remains a challenge. Insect resistant cotton and maize expressing the Bt Vip3Aa protein were recently commercialized, though not yet in Australia. We found that, although relatively high, the frequency of alleles for resistance to Vip3Aa in field populations of H. armigera in Australia did not increase over the past four seasons until 2014/15. Three new isofemale lines were determined to be allelic with previously isolated lines, suggesting that they belong to one common gene and this mechanism is relatively frequent. Vip3Aa-resistance does not confer cross-resistance to Cry1Ac or Cry2Ab. Vip3Aa was labeled with 125I and used to show specific binding to H. armigera brush-border membrane vesicles (BBMV). Binding was of high affinity (Kd = 25 and 19 nM for susceptible and resistant insects, respectively) and the concentration of binding sites was high (Rt = 140 pmol/mg for both). Despite the narrow-spectrum resistance, binding of 125I-labeled Vip3Aa to BBMV of resistant and susceptible insects was not significantly different. Proteolytic conversion of Vip3Aa protoxin into the activated toxin rendered the same products, though it was significantly slower in resistant insects. PMID:27095284

  11. Resistance Risk Assessment of Spodoptera frugiperda (Lepidoptera: Noctuidae) and Diatraea saccharalis (Lepidoptera: Crambidae) to Vip3Aa20 Insecticidal Protein Expressed in Corn.

    PubMed

    Bernardi, Oderlei; Bernardi, Daniel; Amado, Douglas; Sousa, Renan S; Fatoretto, Julio; Medeiros, Fernanda C L; Conville, Jared; Burd, Tony; Omoto, Celso

    2015-12-01

    Transgenic Agrisure Viptera 3 corn that expresses Cry1Ab, Vip3Aa20, and EPSPS proteins and Agrisure Viptera expressing Vip3Aa20 are used for control of Spodoptera frugiperda (J.E. Smith) and Diatraea saccharalis (F.) in Brazil. To support a resistance management program, resistance risk assessment studies were conducted to characterize the dose expression of Vip3Aa20 protein and level of control against these species. The Vip3Aa20 expression in Agrisure Viptera 3 and Agrisure Viptera decreased from V6 to V10 stage of growth. However, Vip3Aa20 expression in Agrisure Viptera 3 at V6 and V10 stages was 13- and 16-fold greater than Cry1Ab, respectively. The Vip3Aa20 expression in lyophilized tissue of Agrisure Viptera 3 and Agrisure Viptera diluted 25-fold in an artificial diet caused complete larval mortality of S. frugiperda and D. saccharalis. In contrast, lyophilized tissue of Bt11 at the same dilution does not provide complete mortality of these species. Agrisure Viptera 3 and Agrisure Viptera also caused a high level of mortality against S. frugiperda and D. saccharalis. Moreover, 100% mortality was observed for S. frugiperda larvae (neonates through fifth-instar larvae) when fed in corn with the Vip trait technology. Viptera corn achieves a high level of control against S. frugiperda and D. saccharalis providing a high dose, which is an important determination to support the refuge strategy for an effective resistance management program.

  12. Transcriptional profiling analysis of Spodoptera litura larvae challenged with Vip3Aa toxin and possible involvement of trypsin in the toxin activation.

    PubMed

    Song, Feifei; Chen, Chen; Wu, Songqing; Shao, Ensi; Li, Mengnan; Guan, Xiong; Huang, Zhipeng

    2016-03-30

    Vip proteins, a new group of insecticidal toxins produced by Bacillus thuringiensis, are effective against specific pests including Spodoptera litura. Here, we report construction of a transcriptome database of S. litura by de novo assembly along with detection of the transcriptional response of S. litura larvae to Vip3Aa toxin. In total, 56,498 unigenes with an N50 value of 1,853 bp were obtained. Results of transcriptome abundance showed that Vip3Aa toxin provoked a wide transcriptional response of the S. litura midgut. The differentially expressed genes were enriched for immunity-related, metabolic-related and Bt-related genes. Twenty-nine immunity-related genes, 102 metabolic-related genes and 62 Bt-related genes with differential expression were found. On the basis of transcriptional profiling analysis, we focus on the functional validation of trypsin which potentially participated in the activation of Vip3Aa protoxin. Zymogram analysis indicated that the presence of many proteases, including trypsin, in S. litura larvae midgut. Results of enzymolysis in vitro of Vip3Aa by trypsin, and bioassay and histopathology of the trypsin-digested Vip3Aa toxin showed that trypsin was possibly involved in the Vip3Aa activation. This study provides a transcriptome foundation for the identification and functional validation of the differentially expressed genes in an agricultural important pest, S. litura.

  13. Characterization of the resistance to Vip3Aa in Helicoverpa armigera from Australia and the role of midgut processing and receptor binding.

    PubMed

    Chakroun, Maissa; Banyuls, Núria; Walsh, Tom; Downes, Sharon; James, Bill; Ferré, Juan

    2016-04-20

    Crops expressing genes from Bacillus thuringiensis (Bt crops) are among the most successful technologies developed for the control of pests but the evolution of resistance to them remains a challenge. Insect resistant cotton and maize expressing the Bt Vip3Aa protein were recently commercialized, though not yet in Australia. We found that, although relatively high, the frequency of alleles for resistance to Vip3Aa in field populations of H. armigera in Australia did not increase over the past four seasons until 2014/15. Three new isofemale lines were determined to be allelic with previously isolated lines, suggesting that they belong to one common gene and this mechanism is relatively frequent. Vip3Aa-resistance does not confer cross-resistance to Cry1Ac or Cry2Ab. Vip3Aa was labeled with (125)I and used to show specific binding to H. armigera brush-border membrane vesicles (BBMV). Binding was of high affinity (Kd = 25 and 19 nM for susceptible and resistant insects, respectively) and the concentration of binding sites was high (Rt = 140 pmol/mg for both). Despite the narrow-spectrum resistance, binding of (125)I-labeled Vip3Aa to BBMV of resistant and susceptible insects was not significantly different. Proteolytic conversion of Vip3Aa protoxin into the activated toxin rendered the same products, though it was significantly slower in resistant insects.

  14. Isolation and partial sequence of the A-protein gene of Thermus thermophilus cytochrome c/sub 1/aa/sub 3/

    SciTech Connect

    Fee, J.A.; Mather, M.W.; Springer, P.; Hensel, S.; Buse, G.

    1988-01-01

    Thermus thermophilus is a strictly aerobic eubacterium which grows optimally near 70/degree/C. Its respiratory system is very similar to that of eukaryotic mitochondria, and the organism has proven to be a particularly good source of stable, comparatively simple respiratory enzymes. There are at least two terminal oxidases: The recently discovered cytochrome ba/sub 3//sup 3/ and cytochrome c/sub 1/aa/sub 3//sup 2/. Cytochrome ba/sub 3/ is analog of aa/sub 3/ in which the heme A of cytochrome a is replaced with protoporphyrin IX (heme B) while its order redox components appear to be largely identical to those of the now classical mammalian cytochrome aa/sub 3/; it has only a single 35 kD protein subunit. Cytochrome c/sub 1/aa/sub 3/ consists of two polypeptides. The /approximately/33 kD C-protein covalently binds one heme C, while the /approximately/55 kD protein is thought to bind the four canonical redox centers of aa/sub 3/, two heme A, and two Cu. Toward our goal of unequivocally establishing the distribution of the metal centers in cytochrome c/sub 1/aa/sub 3/, we have isolated the structural gene of the A-protein. 20 refs., 4 figs.

  15. A naturally occurring -263G/C variant of the human AA-NAT gene and overnight melatonin production.

    PubMed

    Ying, Grace Wang; Lee, Caroline Guat Lay; Lee, Edmund Jon Deoon

    2004-01-01

    Several lines of evidence show that the daily amount of melatonin produced differs greatly between individuals. Any polymorphism in the gene of arylalkylamine N-acetyltransferase (AA-NAT), a critical enzyme involved in melatonin biosynthesis, may contribute to the variability of melatonin production. The present study investigated the possible association between overnight melatonin excretion and a commonly occurring -263G/C polymorphism in the promoter region of the human AA-NAT gene. However, we found that -263G/C variant had no effect on the overnight 6-OHMS excretion. In this study, individual genotyping for -263G/C was determined by denaturing high performance liquid chromatography (DHPLC) and confirmed by sequencing. The overnight urinary 6-hydroxymelatonin sulfate (6-OHMS) excretion was quantified by enzyme-linked immunosorbent assay (ELISA).

  16. Spectroscopic signatures of AA' and AB stacking of chemical vapor deposited bilayer MoS2

    SciTech Connect

    Xia, Ming; Li, Bo; Yin, Kuibo; Capellini, Giovanni; Niu, Gang; Gong, Yongji; Zhou, Wu; Ajayan, Pulickel M.; Xie, Ya -Hong

    2015-11-04

    We discuss prominent resonance Raman and photoluminescence spectroscopic differences between AA'and AB stacked bilayer molybdenum disulfide (MoS2) grown by chemical vapor deposition are reported. Bilayer MoS2 islands consisting of the two stacking orders were obtained under identical growth conditions. Also, resonance Raman and photoluminescence spectra of AA' and AB stacked bilayer MoS2 were obtained on Au nanopyramid surfaces under strong plasmon resonance. Both resonance Raman and photoluminescence spectra show distinct features indicating clear differences in interlayer interaction between these two phases. The implication of these findings on device applications based on spin and valley degrees of freedom.

  17. Two-gluon rapidity correlations of strong colour field in pp, pA and AA collisions

    NASA Astrophysics Data System (ADS)

    Zhao, Ye-Yin; Xu, Ming-Mei; Zhang, Heng-Ying; Wu, Yuan-Fang

    2016-11-01

    Using the CGC formalism, we calculate the two-gluon rapidity correlations of strong colour fields in pp, pA and AA collisions, respectively. If one trigger gluon is fixed at central rapidity, a ridge-like correlation pattern is obtained in symmetry pp and AA collisions, and a huge bump-like correlation pattern is presented in asymmetry pA collisions. It is demonstrated that long-range ridge-like rapidity correlations are caused by the stronger correlation with the gluon of colour source. These features are independent of the azimuthal angular of two selected gluon. They are qualitatively consistent with current observed data at LHC. The transverse momentum and incident energy dependence of the ridge and bump-like correlations are also systematically studied. The ridge is more likely observed at higher incident energy and lower transverse momentum of trigger gluon.

  18. Design and Application of Wuhan Ionospheric Oblique Backscattering Sounding System with the Addition of an Antenna Array (WIOBSS-AA)

    PubMed Central

    Cui, Xiao; Chen, Gang; Wang, Jin; Song, Huan; Gong, Wanlin

    2016-01-01

    The Wuhan Ionospheric Oblique Backscattering Sounding System with the addition of an antenna array (WIOBSS-AA) is the newest member of the WIOBSS family. It is a multi-channel radio system using phased-array antenna technology. The transmitting part of this radio system applies an array composed of five log-periodic antennas to form five beams that span an area to the northwest of the radar site. The hardware and the antenna array of the first multi-channel ionosonde in the WIOBSS family are introduced in detail in this paper. An ionospheric detection experiment was carried out in Chongyang, Hubei province, China on 16 March 2015 to examine the performance of WIOBSS-AA. The radio system demonstrated its ability to obtain ionospheric electron density information over a wide area. The observations indicate that during the experiment, the monitored large-area ionospheric F2-layer was calm and electron density increased with decreasing latitude. PMID:27314360

  19. Design and Application of Wuhan Ionospheric Oblique Backscattering Sounding System with the Addition of an Antenna Array (WIOBSS-AA).

    PubMed

    Cui, Xiao; Chen, Gang; Wang, Jin; Song, Huan; Gong, Wanlin

    2016-06-15

    The Wuhan Ionospheric Oblique Backscattering Sounding System with the addition of an antenna array (WIOBSS-AA) is the newest member of the WIOBSS family. It is a multi-channel radio system using phased-array antenna technology. The transmitting part of this radio system applies an array composed of five log-periodic antennas to form five beams that span an area to the northwest of the radar site. The hardware and the antenna array of the first multi-channel ionosonde in the WIOBSS family are introduced in detail in this paper. An ionospheric detection experiment was carried out in Chongyang, Hubei province, China on 16 March 2015 to examine the performance of WIOBSS-AA. The radio system demonstrated its ability to obtain ionospheric electron density information over a wide area. The observations indicate that during the experiment, the monitored large-area ionospheric F2-layer was calm and electron density increased with decreasing latitude.

  20. The rs2071559 AA VEGFR-2 genotype frequency is significantly lower in neovascular age-related macular degeneration patients.

    PubMed

    Lazzeri, Stefano; Orlandi, Paola; Figus, Michele; Fioravanti, Anna; Cascio, Elisa; Di Desidero, Teresa; Agosta, Elisa; Canu, Bastianina; Sartini, Maria Sole; Danesi, Romano; Nardi, Marco; Bocci, Guido

    2012-01-01

    In this prospective, case-control genetic study, 120 consecutive neovascular age-related macular degeneration (AMD) cases and 78 controls were enrolled. Two SNPs (rs2071559 and rs1870377) of VEGF-A receptor-2 (VEGFR-2) gene were analyzed with the technique of Real-Time PCR to investigate a genetic link between AMD and VEGFR-2 gene polymorphisms in Italian patients. The frequency of the VEGFR-2 genotype rs2071559 AA was significantly lower (18.33%) in patients with AMD than in the control subjects (34.62%; P = 0.0095, chi-square test; P(corr) = 0.038; OR = 0.42, 95% CI 0.22 to 0.82). In conclusion, although with the limitations of a small sample size and the few SNPs studied, this study demonstrates a lower frequency of VEGFR-2 rs2071559 AA genotype in an AMD patient population, suggesting future studies on the role VEGFR-2 SNPs.

  1. The rs2071559 AA VEGFR-2 Genotype Frequency Is Significantly Lower in Neovascular Age-Related Macular Degeneration Patients

    PubMed Central

    Lazzeri, Stefano; Orlandi, Paola; Figus, Michele; Fioravanti, Anna; Cascio, Elisa; Di Desidero, Teresa; Agosta, Elisa; Canu, Bastianina; Sartini, Maria Sole; Danesi, Romano; Nardi, Marco; Bocci, Guido

    2012-01-01

    In this prospective, case-control genetic study, 120 consecutive neovascular age-related macular degeneration (AMD) cases and 78 controls were enrolled. Two SNPs (rs2071559 and rs1870377) of VEGF-A receptor-2 (VEGFR-2) gene were analyzed with the technique of Real-Time PCR to investigate a genetic link between AMD and VEGFR-2 gene polymorphisms in Italian patients. The frequency of the VEGFR-2 genotype rs2071559 AA was significantly lower (18.33%) in patients with AMD than in the control subjects (34.62%; P = 0.0095, chi-square test; Pcorr = 0.038; OR = 0.42, 95% CI 0.22 to 0.82). In conclusion, although with the limitations of a small sample size and the few SNPs studied, this study demonstrates a lower frequency of VEGFR-2 rs2071559 AA genotype in an AMD patient population, suggesting future studies on the role VEGFR-2 SNPs. PMID:22919317

  2. Persistence of Bt Bacillus thuringiensis Cry1Aa toxin in various soils determined by physicochemical reactions

    NASA Astrophysics Data System (ADS)

    Helassa, N.; Noinville, S.; Déjardin, P.; Janot, J. M.; Quiquampoix, H.; Staunton, S.

    2009-04-01

    Insecticidal Cry proteins from the soil bacterium, Bacillus thuringiensis (Bt) are produced by a class of genetically modified (GM) crops, and released into soils through root exudates and upon decomposition of residues. In contrast to the protoxin produced by the Bacillus, the protein produced in GM crops does not require activation in insect midguts and thereby potentially looses some of its species specificity. Although gene transfer and resistance emergence phenomena are well documented, the fate of these toxins in soil has not yet been clearly elucidated. Cry proteins, in common with other proteins, are adsorbed on soils and soil components. Adsorption on soil, and the reversibility of this adsorption is an important aspect of the environmental behaviour of these toxins. The orientation of the molecule and conformational changes on surfaces may modify the toxicity and confer some protection against microbial degradation. Adsorption will have important consequences for both the risk of exposition of non target species and the acquisition of resistance by target species. We have adopted different approaches to investigate the fate of Cry1Aa in soils and model minerals. In each series of experiments we endeavoured to maintain the protein in a monomeric form (pH above 6.5 and a high ionic strength imposed with 150 mM NaCl). The adsorption and the desorbability of the Cry1Aa Bt insecticidal protein were measured on two different homoionic clays: montmorillonite and kaolinite. Adsorption isotherms obtained followed a low affinity interaction for both clays and could be fitted using the Langmuir equation. Binding of the toxin decreased as the pH increased from 6.5 (close to the isoelectric point) to 9. Maximum adsorption was about 40 times greater on montmorillonite (1.71 g g-1) than on kaolinite (0.04 g g-1) in line with the contrasting respective specific surface areas of the minerals. Finally, some of the adsorbed toxin was desorbed by water and more, about 36

  3. Branching ratios and polarization in B{yields}VV,VA,AA decays

    SciTech Connect

    Cheng, H.-Y.; Yang, K.-C.

    2008-11-01

    We present a detailed study of charmless two-body B decays into final states involving two vector mesons (VV) or two axial-vector mesons (AA) or one vector and one axial-vector meson (VA), within the framework of QCD factorization, where A is either a {sup 3}P{sub 1} or {sup 1}P{sub 1} axial-vector meson. The main results are as follows. (i) In the presence of next-to-leading-order nonfactorizable corrections, effective Wilson coefficients a{sub i}{sup h} are helicity-dependent. For some penguin-dominated modes, the constructive (destructive) interference in the negative-helicity (longitudinal-helicity) amplitude of the B{yields}VV decay will render the former comparable to the latter and push up the transverse polarization. (ii) In QCD factorization, the transverse polarization fraction can be large for penguin-dominated charmless VV modes by allowing for sizable penguin-annihilation contributions. (iii) Using the measured K*{sup 0}{rho}{sup -} channel as an input, we predict the branching ratios and polarization fractions for other B{yields}K*{rho} decays. (iv) The smallness of the axial-vector decay constant of the {sup 1}P{sub 1} axial-vector meson can be tested by measuring various b{sub 1}{rho} modes to see if {gamma}(B{sup 0}{yields}b{sub 1}{sup -}{rho}{sup +})<<{gamma}(B{sup 0}{yields}b{sub 1}{sup +}{rho}{sup -}) and {gamma}(B{sup -}{yields}b{sub 1}{sup -}{rho}{sup 0})<<{gamma}(B{sup -}{yields}b{sub 1}{sup 0}{rho}{sup -}). (v) For the penguin-dominated modes a{sub 1}K* and b{sub 1}K*, it is found that the former are dominated by transverse polarization amplitudes, whereas the latter are governed by longitudinal polarization states. (vi) The rates of B{yields}K{sub 1}(1270)K* and K{sub 1}(1400)K* are generally very small. The decay modes K{sub 1}{sup -}K*{sup +} and K{sub 1}{sup +}K*{sup -} are of particular interest as they are the only AV modes which receive contributions solely from weak annihilation. (vii) For tree-dominated B{yields}AA decays, the a

  4. TGF β1 and PDGF AA override Collagen type I inhibition of proliferation in human liver connective tissue cells

    PubMed Central

    Geremias, Alvaro T; Carvalho, Marcelo A; Borojevic, Radovan; Monteiro, Alvaro NA

    2004-01-01

    Background A marked expansion of the connective tissue population and an abnormal deposition of extracellular matrix proteins are hallmarks of chronic and acute injuries to liver tissue. Liver connective tissue cells, also called stellate cells, derived from fibrotic liver have been thoroughly characterized and correspond phenotypically to myofibroblasts. They are thought to derive from fat-storing Ito cells in the perisinusoidal space and acquire a contractile phenotype when activated by tissue injury. In the last few years it has become evident that several peptide growth factors such as PDGF AA and TGF-β are involved in the development of fibrosis by modulating myofibroblast proliferation and collagen secretion. The fact that during the development of chronic fibrosis there is concomitant deposition of collagen, a known inhibitory factor, and sustained cell proliferation, raises the possibility that stellate cells from chronic liver fibrosis patients fail to respond to normal physiologic controls. Methods In this study we address whether cells from fibrotic liver patients respond to normal controls of proliferation. We compared cell proliferation of primary human liver connective tissue cells (LCTC) from patients with liver fibrosis and skin fibroblasts (SF) in the presence of collagens type I and IV; TGF-β, PDGF AA and combinations of collagen type I and TGF-β or PDGF AA. Results Our results indicate that despite displaying normal contact and collagen-induced inhibition of proliferation LCTC respond more vigorously to lower concentrations of PDGF AA. In addition, we show that collagen type I synergizes with growth factors to promote mitogenesis of LCTC but not SF. Conclusions The synergistic interaction of growth factors and extracellular matrix proteins may underlie the development of chronic liver fibrosis. PMID:15579200

  5. AA Fest General Circulation Model Development: Past, Present and Future. A Symposium in Honor of Professor Akio Arakawa

    SciTech Connect

    Ide, Kayo

    1998-01-22

    On January 20-22, 1998, ''AA Fest. A Symposium on General Circulation Model Development: Past, Present, and Future'' was held at the North West Campus Auditorium of University of California, Los Angeles, in honor of Professor Ako Arawaka. The symposium consisted of two-and-a-half-day technical presentations, along with a banquet in the opening evening and a reception during the poster session of the second evening.

  6. Fully Coupled Thermomechanical Finite Element Analysis of Material Evolution During Friction-Stir Welding of AA5083

    DTIC Science & Technology

    2009-09-03

    clamped welding plates and the associated material and heat transport during a friction-stir welding ( FSW ) process are studied computationally using...cylindrical shoulder) with the clamped welding plates and the associated material and heat transport during a friction-stir welding ( FSW ) process are...computational approach, the analysis is applied to the case of FSW of AA5083 (a solid–solution strengthened and strainhardened/ stabilized Al–Mg wrought alloy

  7. Innate BDNF expression is associated with ethanol intake in alcohol-preferring AA and alcohol-avoiding ANA rats.

    PubMed

    Raivio, Noora; Miettinen, Pekka; Kiianmaa, Kalervo

    2014-09-04

    We have shown recently that acute administration of ethanol modulates the expression of brain-derived neurotrophic factor (BDNF) in several rat brain areas known to be involved in the development of addiction to ethanol and other drugs of abuse, suggesting that BDNF may be a factor contributing to the neuroadaptive changes set in motion by ethanol exposure. The purpose of the present study was to further clarify the role of BDNF in reinforcement from ethanol and in the development of addiction to ethanol by specifying the effect of acute administration of ethanol (1.5 or 3.0 g/kg i.p.) on the expression profile of BDNF mRNA in the ventral tegmental area and in the terminal areas of the mesolimbic dopamine pathway in the brain of alcohol-preferring AA and alcohol-avoiding ANA rats, selected for high and low voluntary ethanol intake, respectively. The level of BDNF mRNA expression was higher in the amygdala and ventral tegmental area of AA than in those of ANA rats, and there was a trend for a higher level in the nucleus accumbens. In the amygdala and hippocampus, a biphasic change in the BDNF mRNA levels was detected: the levels were decreased at 3 and 6h but increased above the basal levels at 24h. Furthermore, there was a difference between the AA and ANA lines in the effect of ethanol, the ANA rats showing an increase in BDNF mRNA levels while such a change was not seen in AA rats. These findings suggest that the innate levels of BDNF expression may play a role in the mediation of the reinforcing effects of ethanol and in the control of ethanol intake.

  8. Vip3Aa tolerance response of Helicoverpa armigera populations from a Cry1Ac cotton planting region.

    PubMed

    An, Jingjie; Gao, Yulin; Wu, Kongming; Gould, Fred; Gao, Jianhua; Shen, Zhicheng; Lei, Chaoliang

    2010-12-01

    Transgenic cotton, Gossypium hirsutum L., that expresses the Bacillus thuringiensis (Bt) Cry1Ac toxin, holds great promise in controlling target insect pests. Evolution of resistance by target pests is the primary threat to the continued efficacy of Bt cotton. To thwart pest resistance evolution, a transgenic cotton culitvar that produces two different Bt toxins, cry1Ac and vip3A genes, was proposed as a successor of cry1Ac cotton. This article reports on levels of Vip3Aa tolerance in Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) populations from the Cry1Ac cotton planting region in China based on bioassays of the F1 generation of isofemale lines. In total, 80 isofemale families of H. armigera from Xiajin county of Shandong Province (an intensive Bt cotton planting area) and 93 families from Anci county of Hebei Province (a multiple-crop system including corn [Zea mays L.] , soybean [Glycine max (L.) Merr.], peanut (Arachis hypogaea L.), and Bt cotton) were screened with a discriminating concentration of both Cry1Ac- and Vip3A-containing diets in 2009. From data on the relative average development rates and percentage of larval weight inhibition of F1 full-sib families tested simultaneously on Cry1Ac and Vip3Aa, results indicate that responses to Cry1Ac and Vip3Aa were not genetically correlated in field population ofH. armigera. This indicates that the threat of cross-resistance between Cry1Ac and Vip3A is low in field populations of H. armigera. Thus, the introduction of Vip3Aa/Cry1Ac-producing lines could delay resistance evolution in H. armigera in Bt cotton planting area of China.

  9. Robotized sampling device for graphite furnace atomic absorption spectrometry slurry analysis with Varian SpectrAA instruments

    NASA Astrophysics Data System (ADS)

    Hoenig, Michel; Cilissen, Anne

    1993-08-01

    There is a growing interest in the determination by electrothermal atomic absorption spectrometry (ETAAS) of elements in solid samples without a dissolution stage, to avoid contamination and losses during the preparation of the sample. This approach may be particularly convenient when only small amounts of sample are available. Details of the above-mentioned program for the adaptation of the Gilson sample changer to Varian SpectrAA systems (X,Y,Z positions, timings etc.) are available on request.

  10. Investigation of decolorization of textile wastewater in an anaerobic/aerobic biological activated carbon system (A/A BAC).

    PubMed

    Pasukphun, N; Vinitnantharat, S; Gheewala, S

    2010-04-01

    The aim of this study is to investigate the decolorization in anaerobic/aerobic biological activated carbon (A/A BAC) system. The experiment was divided into 2 stages; stage I is batch test for preliminary study of dye removal equilibrium time. The preliminary experiment (stage I) provided the optimal data for experimental design of A/A BAC system in SBR (stage II). Stage II is A/A BAC system imitated Sequencing Batch Reactor (SBR) which consist of 5 main periods; fill, react, settle, draw and idle. React period include anaerobic phase followed by aerobic phase. The BAC main media; Granular Activated Carbon (GAC), Mixed Cultures (MC) and Biological Activated Carbon (BAC) were used for dye and organic substances removal in three different solutions; Desizing Agent Solution (DAS), dye Solution (DS) and Synthetic Textile Wastewater (STW). Results indicate that GAC adsorption plays role in dye removal followed by BAC and MC activities, respectively. In the presence desizing agent, decolorization by MC was improved because desizing agent acts as co-substrates for microorganisms. It was found that 50% of dye removal efficiency was achieved in Fill period by MC. GC/MS analysis was used to identify dye intermediate from decolorization. Dye intermediate containing amine group was found in the solution and on BAC surfaces. The results demonstrated that combination of MC and BAC in the system promotes decolorization and dye intermediate removal. In order to improve dye removal efficiency in an A/A BAC system, replacement of virgin GAC, sufficient co-substrates supply and the appropriate anaerobic: aerobic period should be considered.

  11. Homing in for New Year: impact parameters and pre-impact orbital evolution of meteoroid 2014 AA

    NASA Astrophysics Data System (ADS)

    de la Fuente Marcos, C.; de la Fuente Marcos, R.; Mialle, P.

    2016-11-01

    On 2008 October 7, small asteroid 2008 TC3 turned itself into the parent body of the first meteor ever to be predicted before entering the Earth's atmosphere. Over five years later, the 2014 AA event became the second instance of such an occurrence. The uncertainties associated with the pre-impact orbit of 2008 TC3 are relatively small because thousands of observations were made during the hours preceding the actual meteor airburst. In sharp contrast, 2014 AA was only observed seven times before impact and consequently its trajectory is somewhat uncertain. Here, we present a recalculation of the impact parameters—location and timing—of this meteor based on infrasound recordings. The new values—(λ_{impact}, φ_{impact}, t_{impact}) = (-44°, +11°, 2456659.618 JD UTC)—and their uncertainties together with Monte Carlo and N-body techniques, are applied to obtain an independent determination of the pre-impact orbit of 2014 AA: a=1.1623 AU, e=0.2116, i=1.4156°, Ω =101.6086°, and ω=52.3393°. Our orbital solution is used to investigate the possible presence of known near-Earth objects (NEOs) moving in similar orbits. Among the objects singled out by this search, the largest is 2013 HO_{11} with an absolute magnitude of 23.0 (diameter 75-169 m) and a MOID of 0.006 AU. Prior to impact, 2014 AA was subjected to a web of overlapping secular resonances and it followed a path similar to those of 2011 GJ3, 2011 JV_{10}, 2012 DJ_{54}, and 2013 NJ4. NEOs in this transient group have their orbits controlled by close encounters with the Earth-Moon system at perihelion and Mars at aphelion, perhaps constituting a dynamical family. Extensive comparison with other studies is also presented.

  12. Determination of total arsenic content in water by atomic absorption spectroscopy (AAS) using vapour generation assembly (VGA).

    PubMed

    Behari, Jai Raj; Prakash, Rajiv

    2006-03-01

    Analysis of arsenic in water is important in view of contamination of ground water with arsenic in some parts of the world including West Bengal in India and neighboring country Bangladesh. WHO has fixed the threshold for arsenic in drinking water to 10ppb (microg/l) level, hence the methodology for determination of arsenic is required to be sensitive at ppb level. Atomic absorption spectrophotometry with vapour generation assembly (AAS-VGA) is well known technique for the trace analysis of arsenic. However, total arsenic analysis [As(III)+As(V)] is very crucial and it requires reduction of As(V) to As(III) for correct analysis. As(III) is reduced to AsH3 vapours and finally to free As atoms, which are responsible for absorption signal in AAS. To accomplish this the vapour generation assembly attached to AAS has acid channel filled with 10 M HCl and the reduction channel with sodium borohydride. Further sample can be reduced either before aspiration for analysis, using potassium iodide (KI) or the sample can be introduced in the instrument directly and KI can be added in the reduction channel along with the sodium borohydride. The present work shows that samples prepared in 3 M HCl can be reduced with KI for 30 min before introduction in the instrument. Alternatively samples can be prepared in 6 M HCl and directly aspirated in AAS using KI in VGA reduction channel. The latter methodology is more useful when the sample size is large and time cycle is difficult to maintain. It is observed that the acid concentration of the sample in both the situations plays an important role. Further reduction in acid concentration and analysis time is achieved for the arsenic analysis by using modified method. Analysis in both the methods is sensitive at ppb level.

  13. Effect of Postweld Aging Treatment on Fatigue Behavior of Pulsed Current Welded AA7075 Aluminum Alloy Joints

    NASA Astrophysics Data System (ADS)

    Balasubramanian, V.; Ravisankar, V.; Madhusudhan Reddy, G.

    2008-04-01

    This article reports the effect of postweld aging treatment on fatigue behavior of pulsed current welded AA 7075 aluminum alloy joints. AA7075 aluminum alloy (Al-Zn-Mg-Cu alloy) has gathered wide acceptance in the fabrication of light weight structures requiring high strength-to weight ratio, such as transportable bridge girders, military vehicles, road tankers, and railway transport systems. The preferred welding processes of AA7075 aluminum alloy are frequently gas tungsten arc welding (GTAW) process and gas metal arc welding (GMAW) process due to their comparatively easier applicability and better economy. Weld fusion zones typically exhibit coarse columnar grains because of the prevailing thermal conditions during weld metal solidification. This often results inferior weld mechanical properties and poor resistance to hot cracking. In this investigation, an attempt has been made to refine the fusion zone grains by applying pulsed current welding technique. Rolled plates of 10 mm thickness have been used as the base material for preparing multipass welded joints. Single V butt joint configuration has been prepared for joining the plates. The filler metal used for joining the plates is AA 5356 (Al-5Mg (wt.%)) grade aluminum alloy. Four different welding techniques have been used to fabricate the joints and they are: (i) continuous current GTAW (CCGTAW), (ii) pulsed current GTAW (PCGTAW), (iii) continuous current GMAW (CCGMAW), and (iv) pulsed current GMAW (PCGMAW) processes. Argon (99.99% pure) has been used as the shielding gas. Rotary bending fatigue testing machine has been used to evaluate fatigue behavior of the welded joints. Current pulsing leads to relatively finer and more equi-axed grain structure in GTA and GMA welds. Grain refinement is accompanied by an increase in fatigue life and endurance limit. Simple postweld aging treatment applied to the joints is found to be beneficial to enhance the fatigue performance of the welded joints.

  14. Synthesis of ST7612AA1, a Novel Oral HDAC Inhibitor, via Radical 
Thioacetic Acid Addition

    PubMed Central

    Battistuzzi, Gianfranco; Giannini, Giuseppe

    2016-01-01

    Abstract: Background In the expanding field of anticancer drugs, HDAC inhibitors are playing an increasingly important role. To date, four/five HDAC inhibitors have been approved by FDA. All these compounds fit the widely accepted HDAC inhibitors pharmacophore model characterized by a cap group, a linker chain and a zinc binding group (ZBG), able to bind the Zn2+ ion in a pocket of the HDAC active site. Romidepsin, a natural compound, is the only thiol derivative. We have selected a new class of synthetic HDAC inhibitors, the thio-ω(lactam-carboxamide) derivatives, with ST7612AA1 as drug candidate, pan-inhibitor active in the range of single- to two-digit nanomolar concentrations. Preliminary results of a synthetic optimization attempt towards a fast scale-up process are here proposed. Methods In the four steps of synthesis, from unsaturated amino acid intermediate to the final product, we explored different synthetic conditions in order to have a transferable process for a scale-up synthetic laboratory. Results In the first step, isobutyl chloroformate was used and, after a simple work up with 1M HCl, 2 (96% yield) was obtained as a white solid, which was used directly in the next step. For thioacetic acid addition to the double bond of intermediate 2, two different routes were possible, with addition reaction in the first (D’) or last step (D). Reactions of 2 to give 5 or of 4 to give ST7612AA1 were both performed in dioxane. Reactions were fast and did not need the usually advised radical quenching with cyclohexene. The corresponding products were obtained in good yields (step D’, 89%; step D, 81%) after a flash chromatography. Conclusion: ST7612AA1 , a thiol derivative prodrug of ST7464AA1, is the first of a new generation of HDAC inhibitors, very potent, orally administered, and well tolerated. Here, we have identified a synthetic route, competitive, versatile and easily transferable to industrial processes. PMID:27917100

  15. Looking on the bright side: The story of AA Doradus as revealed by its cool companion

    NASA Astrophysics Data System (ADS)

    Vučković, M.; Østensen, R. H.; Németh, P.; Bloemen, S.; Pápics, P. I.

    2016-02-01

    The effects of irradiation on the secondary stars of close binary systems are crucial for reliably determining the system parameters and for understanding the close binary evolution. They affect the stellar structure of the irradiated star and are reflected in the appearance of characteristic features in the spectroscopic and photometric data of these systems. We aim to study the light that originates from the irradiated side of the low-mass component of a close binary eclipsing system, which comprises a hot subdwarf primary and a low mass companion, to precisely interpret their high precision photometric and spectroscopic data, and accurately determine their system and surface parameters. We reanalyse the archival high-resolution time-resolved VLT/UVES spectra of AA Dor system, where irradiation features have already been detected. After removing the predominant contribution of the hot subdwarf primary, the residual spectra reveal more than 100 emission lines from the heated side of the secondary, which show maximum intensity close to the phases around the secondary eclipse. We analyse the residual spectrum to model the irradiation of the low-mass secondary. We perform a detailed analysis of 22 narrow emission lines of the irradiated secondary, mainly of O ii, with a few significant C ii lines. Their phase profiles constrain the emission region of the heated side to a radius ≥95% of the radius of the secondary, while the shape of their velocity profiles reveals two distinct asymmetry features, one at the quadrature and the other at the secondary eclipse. In addition, we identify weaker emission signatures originating from more than 70 lines, including lines from He i, N ii, Si iii, Ca ii, and Mg ii. From the emission lines of the heated side of the secondary star, we determine the radial velocity semi-amplitude of the centre-of-light and correct it to the centre-of-mass of the secondary which, in turn, gives accurate masses of both components of the AA Dor

  16. Long-term kinetics of AA amyloidosis and effects of inflammatory restimulation after disappearance of amyloid depositions in mice.

    PubMed

    Muhammad, N; Murakami, T; Inoshima, Y; Ishiguro, N

    2015-07-01

    Amyloid A (AA) amyloidosis is characterized by extracellular pathogenic deposition of insoluble fibril protein in various body organs. Deposited amyloid generally remains in a variety of organs for long periods, but its disappearance has been reported after the precursor protein is diminished. The kinetics of AA deposition are not completely understood and, in particular, the roles of cells and cytokines in the deposition and clearance of amyloid remain unclear. In this study, we investigated the disappearance of amyloid depositions in mice over a 1-year period. AA amyloidosis was induced experimentally in mice by injecting amyloid-enhancing factor (AEF) and silver nitrate. Mice were killed at different time-points to examine the occurrence and disappearance of amyloid depositions. Maximum levels of amyloid depositions were observed at 20 days after inoculation. Clearance of amyloid depositions was observed from the 40th day onwards, with only minute traces of amyloid present by 240 days. A second inflammatory stimulus consisting of AEF and silver nitrate was given at 330 or 430 days, after amyloid depositions had disappeared almost completely. After that, serum amyloid A was overproduced and redeposition of amyloid was observed, indicating that all mice were primed for aggressive amyloid depositions. After administration of the inflammatory stimuli, the proinflammatory environment was found to have increased levels of interleukin (IL)-6, while anti-inflammatory conditions were established by IL-10 as regression of amyloid deposition occurred. These results suggest that the proinflammatory and anti-inflammatory status have key roles in both amyloid deposition and clearance.

  17. Microstructure, Hardness and Impact Toughness of Heat-Treated Nanodispersed Surface and Friction Stir-Processed Aluminum Alloy AA7075

    NASA Astrophysics Data System (ADS)

    Refat, M.; Elashery, A.; Toschi, S.; Ahmed, M. M. Z.; Morri, A.; El-Mahallawi, I.; Ceschini, L.

    2016-11-01

    Friction stir processing (FSP) is a recent surface engineering processing technique that is gaining wide recognition for manufacturing nanodispersed surface composites, which are of high specific strength, hardness and resistance to wear and corrosion. Herein, four-pass FSP was applied on aluminum alloy 7075 (AA7075-O) with and without the addition of alumina nanoparticles (Al2O3) of average size 40 nm. All FSP parameters were constant at 40 mm/min transverse speed, 500 rpm and tilt angle of 3°. FSP rotation direction was reversed every other pass. The friction stir-processed materials were sectioned and solution treated at 515 °C for 1.5 h, followed by age hardening at 120 °C for 12, 24, 36, 48 and 60 h. The effect of heat treatment regimes on microstructure, hardness and toughness was examined, as well as the fracture mode. The new friction stir-processed surfaces without and with nanodispersion showed enhancement in the hardness of the surface of the AA7075-O material (65 HV) to almost a double (100 and 140 HV) after four-pass FSP (before heat treatment) without and with incorporating nanoalumina particles, respectively. After 48-h aging at 120 °C, a significant enhancement in impact toughness was achieved for both the friction stir-processed without and with nanodispersion (181 and 134 J, respectively), compared to the reference material AA7075 in T6 condition (104 J).

  18. HBV Viral Load and Liver Enzyme Levels May Be Associated with the Wild MBL2 AA Genotype

    PubMed Central

    Moura, Tuane Carolina Ferreira; Araújo, Mauro Sérgio; Freitas Queiroz, Maria Alice; Conde, Simone Regina Souza da Silva; Demachki, Sâmia; Martins-Feitosa, Rosimar Neris; Machado, Luiz Fernando Almeida; Cayres-Vallinoto, Izaura Maria Vieira; Ishak, Ricardo

    2017-01-01

    The present study investigated the frequencies of rs1800450 (MBL ⁎B, G>A), rs1800451 (MBL ⁎C, G>A), and rs5030737 (MBL ⁎D, C>T) polymorphisms in exon 1 of the MBL2 gene among patients with chronic viral hepatitis. Blood samples from patients infected with hepatitis B virus (HBV; n = 65), hepatitis C virus (HCV; n = 92), and a noninfected control group (n = 300) were investigated. The presence of polymorphisms was detected using a real-time polymerase chain reaction to correlate with liver disease pathogenesis and fibrosis staging according to the Metavir classification. The genotypic and allelic frequencies showed no significant differences between the groups, but patients with active HBV and the wild AA genotype presented a positive correlation between increased transaminase and HBV DNA levels and the presence of mild to moderate fibrosis. Patients with HCV and the wild AA genotype presented mild inflammation and higher HCV RNA levels, although the same association was not observed for the fibrosis scores. The results suggest that the mutations in exon 1 of the MBL2 gene do not contribute directly to the clinical and laboratory features of HCV and HBV infections, but further studies should be performed to confirm whether the wild AA genotype has indirect effect on disease progression.

  19. Measurements and Modeling of Stress in Precipitation-Hardened Aluminum Alloy AA2618 during Gleeble Interrupted Quenching and Constrained Cooling

    NASA Astrophysics Data System (ADS)

    Chobaut, Nicolas; Carron, Denis; Saelzle, Peter; Drezet, Jean-Marie

    2016-11-01

    Solutionizing and quenching are the key steps in the fabrication of heat-treatable aluminum parts such as AA2618 compressor impellers for turbochargers as they highly impact the mechanical characteristics of the product. In particular, quenching induces residual stresses that can cause unacceptable distortions during machining and unfavorable stresses in service. Predicting and controlling stress generation during quenching of large AA2618 forgings are therefore of particular interest. Since possible precipitation during quenching may affect the local yield strength of the material and thus impact the level of macroscale residual stresses, consideration of this phenomenon is required. A material model accounting for precipitation in a simple but realistic way is presented. Instead of modeling precipitation that occurs during quenching, the model parameters are identified using a limited number of tensile tests achieved after representative interrupted cooling paths in a Gleeble machine. This material model is presented, calibrated, and validated against constrained coolings in a Gleeble blocked-jaws configuration. Applications of this model are FE computations of stress generation during quenching of large AA2618 forgings for compressor impellers.

  20. How EF-Tu can contribute to efficient proofreading of aa-tRNA by the ribosome

    PubMed Central

    Noel, Jeffrey K.; Whitford, Paul C.

    2016-01-01

    It has long been recognized that the thermodynamics of mRNA–tRNA base pairing is insufficient to explain the high fidelity and efficiency of aminoacyl-tRNA (aa-tRNA) selection by the ribosome. To rationalize this apparent inconsistency, Hopfield proposed that the ribosome may improve accuracy by utilizing a multi-step kinetic proofreading mechanism. While biochemical, structural and single-molecule studies have provided a detailed characterization of aa-tRNA selection, there is a limited understanding of how the physical–chemical properties of the ribosome enable proofreading. To this end, we probe the role of EF-Tu during aa-tRNA accommodation (the proofreading step) through the use of energy landscape principles, molecular dynamics simulations and kinetic models. We find that the steric composition of EF-Tu can reduce the free-energy barrier associated with the first step of accommodation: elbow accommodation. We interpret this effect within an extended kinetic model of accommodation and show how EF-Tu can contribute to efficient and accurate proofreading. PMID:27796304

  1. Zwitterionic Iron Oxide (γ-Fe2 O3 ) Nanoparticles Based on P(2VP-grad-AA) Copolymers.

    PubMed

    Billing, Mark; Gräfe, Christine; Saal, Adrian; Biehl, Philip; Clement, Joachim H; Dutz, Silvio; Weidner, Steffen; Schacher, Felix H

    2017-02-01

    This study presents the synthesis and characterization of zwitterionic core-shell hybrid nanoparticles consisting of a core of iron oxide multicore nanoparticles (MCNPs, γ-Fe2 O3 ) and a shell of sultonated poly(2-vinylpyridine-grad-acrylic acid) copolymers. The gradient copolymers are prepared by reversible addition fragmentation chain transfer polymerization of 2-vinylpyridine (2VP), followed by the addition of tert-butyl acrylate and subsequent hydrolysis. Grafting of P(2VP-grad-AA) onto MCNP results in P(2VP-grad-AA)@MCNP, followed by quaternization using 1,3-propanesultone-leading to P(2VPS -grad-AA)@MCNP with a zwitterionic shell. The resulting particles are characterized by transmission electron microscopy, dynamic light scattering, and thermogravimetric analysis measurements, showing particle diameters of ≈70-90 nm and an overall content of the copolymer shell of ≈10%. Turbidity measurements indicate increased stability toward secondary aggregation after coating if compared to the pristine MCNP and additional cytotoxicity tests do not reveal any significant influence on cell viability.

  2. Effects of Different Filler Metals on the Mechanical Behaviors of GTA Welded AA7A52(T6)

    NASA Astrophysics Data System (ADS)

    Shu, Fengyuan; Lv, Yaohui; Liu, Yuxin; Lin, Jianjun; Sun, Zhe; Xu, Binshi; He, Peng

    2014-06-01

    ER4043, ER5356, and AA7A52 on behalf of the Al-Si, Al-Mg, and Al-Zn-Mg-based welding material, respectively, were chosen as the filler metal to weld AA7A52(T6) plates by GTAW. The variance in mechanical performances of the joints caused by the various filler materials was investigated with reference to the SEM and EDS test results for the weld seam and the fracture surface. Failure was found in the seam for all the welded joints. With regard to the joint obtained with ER4043 welding wire, the total elongation was limited by the brittle intergranular compound Mg2Si of which Mg was introduced by convection mass transfer. As for the other two welds, the content ratio of Zn and Mg was found to play the dominant role in deciding the mechanical properties of the intergranular Mg-Zn compounds which were responsible for the tensile behavior of the joints. The content ratio (wt.%) of beyond 2:1 gave birth to the strengthening phase MgZn2 leading to a ductile fracture. Cr in the seam obtained with AA7A52 filler metal was found to enhance the strength of the joint through isolated particles.

  3. How EF-Tu can contribute to efficient proofreading of aa-tRNA by the ribosome

    NASA Astrophysics Data System (ADS)

    Noel, Jeffrey K.; Whitford, Paul C.

    2016-10-01

    It has long been recognized that the thermodynamics of mRNA-tRNA base pairing is insufficient to explain the high fidelity and efficiency of aminoacyl-tRNA (aa-tRNA) selection by the ribosome. To rationalize this apparent inconsistency, Hopfield proposed that the ribosome may improve accuracy by utilizing a multi-step kinetic proofreading mechanism. While biochemical, structural and single-molecule studies have provided a detailed characterization of aa-tRNA selection, there is a limited understanding of how the physical-chemical properties of the ribosome enable proofreading. To this end, we probe the role of EF-Tu during aa-tRNA accommodation (the proofreading step) through the use of energy landscape principles, molecular dynamics simulations and kinetic models. We find that the steric composition of EF-Tu can reduce the free-energy barrier associated with the first step of accommodation: elbow accommodation. We interpret this effect within an extended kinetic model of accommodation and show how EF-Tu can contribute to efficient and accurate proofreading.

  4. Influences of post weld heat treatment on tensile properties of friction stir welded AA2519-T87 aluminium alloy joints

    NASA Astrophysics Data System (ADS)

    Sabari, S. Sree; Balasubramanian, V.; Malarvizhi, S.; Reddy, G. Madusudhan

    2015-12-01

    AA 2519-T87 is an aluminium alloy that principally contains Cu as an alloying element and is a new grade of Al-Cu alloy system. This material is a potential candidate for light combat military vehicles. Fusion welding of this alloy leads to hot cracking, porosity and alloy segregation in the weld metal region. Friction stir welding (FSW) is a solid state joining process which can overcome the above mentioned problems. However, the FSW of age hardenable aluminium alloys results in poor tensile properties in the as-welded condition (AW). Hence, post weld heat treatment (PWHT) is used to enhance deteriorated tensile properties of FSW joints. In this work, the effect of PWHT, namely artificial ageing (AA) and solution treatment (ST) followed by ageing (STA) on the microstructure, tensile properties and microhardness were systematically investigated. The microstructural features of the weld joints were characterised using an optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The tensile strength and microhardness of the joints were correlated with the grain size, precipitate size, shape and its distribution. From the investigation, it was found that STA treatment is beneficial in enhancing the tensile strength of the FSW joints of AA2519-T87 alloy and this is mainly due to the presence of fine and densely distributed precipitates in the stir zone.

  5. Dopamine transporter comparative molecular modeling and binding site prediction using the LeuT(Aa) leucine transporter as a template.

    PubMed

    Indarte, Martín; Madura, Jeffry D; Surratt, Christopher K

    2008-02-15

    Pharmacological and behavioral studies indicate that binding of cocaine and the amphetamines by the dopamine transporter (DAT) protein is principally responsible for initiating the euphoria and addiction associated with these drugs. The lack of an X-ray crystal structure for the DAT or any other member of the neurotransmitter:sodium symporter (NSS) family has hindered understanding of psychostimulant recognition at the atomic level; structural information has been obtained largely from mutagenesis and biophysical studies. The recent publication of a crystal structure for the bacterial leucine transporter LeuT(Aa), a distantly related NSS family homolog, provides for the first time a template for three-dimensional comparative modeling of NSS proteins. A novel computational modeling approach using the capabilities of the Molecular Operating Environment program MOE 2005.06 in conjunction with other comparative modeling servers generated the LeuT(Aa)-directed DAT model. Probable dopamine and amphetamine binding sites were identified within the DAT model using multiple docking approaches. Binding sites for the substrate ligands (dopamine and amphetamine) overlapped substantially with the analogous region of the LeuT(Aa) crystal structure for the substrate leucine. The docking predictions implicated DAT side chains known to be critical for high affinity ligand binding and suggest novel mutagenesis targets in elucidating discrete substrate and inhibitor binding sites. The DAT model may guide DAT ligand QSAR studies, and rational design of novel DAT-binding therapeutics.

  6. Structure and Biosynthesis of Amychelin, an Unusual Mixed-Ligand Siderophore from Amycolatopsis sp. AA4

    PubMed Central

    2011-01-01

    Actinobacteria generate a large number of structurally diverse small molecules with potential therapeutic value. Genomic analyses of this productive group of bacteria show that their genetic potential to manufacture small molecules exceeds their observed ability by roughly an order of magnitude, and this revelation has prompted a number of studies to identify members of the unknown majority. As a potential window into this cryptic secondary metabolome, pairwise assays for developmental interactions within a set of 20 sequenced actinomycetes were carried out. These assays revealed that Amycolatopsis sp. AA4, a so-called “rare” actinomycete, produces a novel siderophore, amychelin, which alters the developmental processes of several neighboring streptomycetes. Using this phenotype as an assay, we isolated amychelin and solved its structure by NMR and MS methods coupled with an X-ray crystallographic analysis of its Fe-complex. The iron binding affinity of amychelin was determined using EDTA competition assays, and a biosynthetic cluster was identified and annotated to provide a tentative biosynthetic scheme for amychelin. PMID:21699219

  7. Rapid diversification of five Oryza AA genomes associated with rice adaptation.

    PubMed

    Zhang, Qun-Jie; Zhu, Ting; Xia, En-Hua; Shi, Chao; Liu, Yun-Long; Zhang, Yun; Liu, Yuan; Jiang, Wen-Kai; Zhao, You-Jie; Mao, Shu-Yan; Zhang, Li-Ping; Huang, Hui; Jiao, Jun-Ying; Xu, Ping-Zhen; Yao, Qiu-Yang; Zeng, Fan-Chun; Yang, Li-Li; Gao, Ju; Tao, Da-Yun; Wang, Yue-Ju; Bennetzen, Jeffrey L; Gao, Li-Zhi

    2014-11-18

    Comparative genomic analyses among closely related species can greatly enhance our understanding of plant gene and genome evolution. We report de novo-assembled AA-genome sequences for Oryza nivara, Oryza glaberrima, Oryza barthii, Oryza glumaepatula, and Oryza meridionalis. Our analyses reveal massive levels of genomic structural variation, including segmental duplication and rapid gene family turnover, with particularly high instability in defense-related genes. We show, on a genomic scale, how lineage-specific expansion or contraction of gene families has led to their morphological and reproductive diversification, thus enlightening the evolutionary process of speciation and adaptation. Despite strong purifying selective pressures on most Oryza genes, we documented a large number of positively selected genes, especially those genes involved in flower development, reproduction, and resistance-related processes. These diversifying genes are expected to have played key roles in adaptations to their ecological niches in Asia, South America, Africa and Australia. Extensive variation in noncoding RNA gene numbers, function enrichment, and rates of sequence divergence might also help account for the different genetic adaptations of these rice species. Collectively, these resources provide new opportunities for evolutionary genomics, numerous insights into recent speciation, a valuable database of functional variation for crop improvement, and tools for efficient conservation of wild rice germplasm.

  8. Resistance Spot Welding of AA5052 Sheet Metal of Dissimilar Thickness

    NASA Astrophysics Data System (ADS)

    Mat Din, N. A.; Zuhailawati, H.; Anasyida, A. S.

    2016-02-01

    Resistance spot welding of dissimilar thickness of AA5052 aluminum alloy was performed in order to investigate the effect of metal thickness on the weldment strength. Resistance spot welding was done using a spot welder machine available in Coraza Systems Sdn Bhd using a hemispherical of chromium copper electrode tip with radius of 6.00 mm under 14 kA of current and 0.02 bar of pressure for all thickness combinations. Lap joint configuration was produced between 2.0 mm thick sheet and 1.2 - 3.2 mm thick sheet, respectively. Microstructure of joint showed asymmetrical nugget shape that was larger on the thicker side indicating larger molten metal volume. Joint 2.0 mm x 3.2 mm sheets has the lowest hardness in both transverse direction and through thickness direction because less heat left in the weld nugget. The microstructure shows that this joint has coarse grains of HAZ. As thickness of sheet metal increased, the failure load of the joints increased. However, there was no linear correlation established between joint strength and metal thickness due to different shape of fusion zone in dissimilar thickness sheet metal.

  9. HIGH-RESOLUTION SPECTROSCOPY OF [Ne II] EMISSION FROM AA Tau AND GM Aur

    SciTech Connect

    Najita, Joan R.; Doppmann, Greg W.; Bitner, Martin A.; Richter, Matthew J.; Lacy, John H.; Jaffe, Daniel T.; Carr, John S.; Meijerink, Rowin; Blake, Geoffrey A.; Herczeg, Gregory J.; Glassgold, Alfred E.

    2009-05-20

    We present high-resolution (R = 80,000) spectroscopy of [Ne II] emission from two young stars, GM Aur and AA Tau, which have moderate to high inclinations. The emission from both sources appears centered near the stellar velocity and is broader than the [Ne II] emission measured previously for the face-on disk system TW Hya. These properties are consistent with a disk origin for the [Ne II] emission we detect, with disk rotation (rather than photoevaporation or turbulence in a hot disk atmosphere) playing the dominant role in the origin of the line width. In the non-face-on systems, the [Ne II] emission is narrower than the CO fundamental emission from the same sources. If the widths of both diagnostics are dominated by Keplerian rotation, this suggests that the [Ne II] emission arises from larger disk radii on average than does the CO emission. The equivalent width of the [Ne II] emission we detect is less than that of the spectrally unresolved [Ne II] feature in the Spitzer spectra of the same sources. Variability in the [Ne II] emission or the mid-infrared continuum, a spatially extended [Ne II] component, or a very (spectrally) broad [Ne II] component might account for the difference in the equivalent widths.

  10. Ifluence of crystallization and entrainment of cooler material on the emplacement of basaltic aa lava flows

    NASA Technical Reports Server (NTRS)

    Crisp, Joy; Baloga, Stephen

    1994-01-01

    A theoretical model is used to describe and investigate the effects of simultaneous crystallization, radiation loss, and entrainment of cooler material on the temperature of a well-mixed core of an active aa lava flow. Entrainment of crust, levee debris, and base material into the interior of active flows has been observed, but the degree of assimilation and the thermal consequences are difficult to quantify. The rate of entrainment can be constrained by supplementing the theoretical model with information on the crystallization along the path of the flow and estimation of the radiative loss from the flow interior. Application of the model is demonstrated with the 1984 Mauna Loa flow, which was erupted about 30 C undercooled. Without any entrainment of cooler material, the high crystallization rates would have driven temperatures in the core wall above temperatures measured by thermocouple and estimated from glass geothermometry. One plausible scenario for this flow, which agrees with available temperature and crystallinity measurements, has a high initial rate of entrainment during the first 8 hours of travel (a mass ratio of entrained material to fluid core of about 15% if the average temperature of the entrained material was 600 C), which counterbalances the latent heat from approximately 40% crystallization. In this scenario, the model suggests an additional 5% crystallization and a 5% entrainment mass ratio over the subsequent 16-hour period. Measurements of crystallization, radiative losses, and entrainment factors are necessary for understanding the detailed thermal histories of active lava flows.

  11. Some observations on cyclic deformation structures in the high-strength commercial aluminum alloy AA 7150

    SciTech Connect

    Hanlon, D.N.; Rainforth, W.M.

    1998-11-01

    Load-controlled fatigue testing of the aluminum alloy AA 7150 has been conducted using four-point bending with an R ratio of + 0.1 over a range of maximum stress levels from 60 to 120% of the 0.2% proof stress. The alloy, in the form of 12.5-mm rolled plate, was investigated in underaged (UA), peak-aged (PA), and overaged (OA) conditions, corresponding to a change in average precipitate sizes from 5 nm in the UA condition to 21 nm in the OA condition. Three orientations of the plate were investigated. Orientation and aging condition influenced the degree of surface topographical development but not fatigue life. Detailed transmission electron microscopy (TEM) of the fatigued surface indicated that deformation in all aging conditions occurred by planar slip. Slip was generally restricted to a single slip system within each grain, and subgrain boundaries offered little resistance to dislocation movement facilitating long slip line lengths (measured up to 310 {micro}m) between adjacent high-angle grain boundaries. Planar slip observed in the OA condition is attributed to shearing of large strengthening precipitates, which is promoted by long slip line lengths. No evidence of surface specific changes in slip character was observed.

  12. Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs

    SciTech Connect

    Drezet, J.-M.; Ludwig, O.; Heinrich, B.

    2007-04-07

    In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking due to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.

  13. Virtual Reality Astronomy Education Using AAS WorldWide Telescope and Oculus Rift

    NASA Astrophysics Data System (ADS)

    Weigel, A. David; Moraitis, Christina D.

    2017-01-01

    The Boyd E. Christenberry Planetarium at Samford University (Birmingham, AL) offers family friendly, live, and interactive planetarium presentations that educate the public on topics from astronomy basics to current cutting edge astronomical discoveries. With limited funding, it is not possible to provide state of the art planetarium hardware for these community audiences. In a society in which many people, even young children, have access to high resolution smart phones and highly realistic video games, it is important to leverage cutting-edge technology to intrigue young and old minds alike. We use an Oculus Rift virtual reality headset running AAS WorldWide Telescope software to visualize 3D data in a fully immersive environment. We create interactive experiences and videos to highlight astronomical concepts and also to communicate the beauty of our universe. The ease of portability enables us to set up at Virtual Reality (VR) experience at various events, festivals, and even in classrooms to provide a community outreach that a fixed planetarium cannot. This VR experience adds the “wow” factor that encourages children and adults to engage in our various planetarium events to learn more about astronomy and continue to explore the final frontier of space. These VR experiences encourages our college students to participate in our astronomy education resulting in increased interest in STEM fields, particularly physics and math.

  14. Comparative Physical Mapping Between Oryza sativa (AA Genome Type) and O. punctata (BB Genome Type)

    PubMed Central

    Kim, HyeRan; Miguel, Phillip San; Nelson, William; Collura, Kristi; Wissotski, Marina; Walling, Jason G.; Kim, Jun Pyo; Jackson, Scott A.; Soderlund, Carol; Wing, Rod A.

    2007-01-01

    A comparative physical map of the AA genome (Oryza sativa) and the BB genome (O. punctata) was constructed by aligning a physical map of O. punctata, deduced from 63,942 BAC end sequences (BESs) and 34,224 fingerprints, onto the O. sativa genome sequence. The level of conservation of each chromosome between the two species was determined by calculating a ratio of BES alignments. The alignment result suggests more divergence of intergenic and repeat regions in comparison to gene-rich regions. Further, this characteristic enabled localization of heterochromatic and euchromatic regions for each chromosome of both species. The alignment identified 16 locations containing expansions, contractions, inversions, and transpositions. By aligning 40% of the punctata BES on the map, 87% of the punctata FPC map covered 98% of the O. sativa genome sequence. The genome size of O. punctata was estimated to be 8% larger than that of O. sativa with individual chromosome differences of 1.5–16.5%. The sum of expansions and contractions observed in regions >500 kb were similar, suggesting that most of the contractions/expansions contributing to the genome size difference between the two species are small, thus preserving the macro-collinearity between these species, which diverged ∼2 million years ago. PMID:17339227

  15. Comparison of a new photosensitizer with erythrosine B in an AA/PVA-based photopolymer material.

    PubMed

    Qi, Yue; Li, Haoyu; Fouassier, Jean Pierre; Lalevée, Jacques; Sheridan, John T

    2014-02-20

    Dyes often act as the photoinitiator PI/photosensitizer PS in photopolymer materials and are therefore of significant interest. The properties of the PI/PS used strongly influences grating formation when the material layer is exposed holographically. In this paper, the ability of a recently synthesized dye, D_1, to sensitize an acrylamide/polyvinyl alcohol (AA/PVA) based photopolymer is examined, and the material performance is characterized using an extended nonlocal photopolymerization-driven diffusion model. Electron spin resonance spin-trapping (ESR-ST) experiments are also carried out to characterize the generation of the initiator/primary radical, R(•), during exposure. The results obtained are then compared with those for the corresponding situation when using a xanthene dye, i.e., erythrosine B, under the same experiment conditions. The results indicate that the nonlocal effect is greater when this new photosensitizer is used in the material. Analysis indicates that this is the case because of the dye's (D_1) weak absorptivity and the resulting slow rate of primary radical production.

  16. [Application of AAS to detecting the influence of railway on the soil of navel orange garden].

    PubMed

    Liu, Hao; Chen, Li-Ping; Ai, Ying-Wei; Pei, Juan; L I, Wei; Zhou, Nan-Hua; Guo, Cong

    2010-06-01

    Railway transportation has boosted the economy of railway road area, meanwhile it brings some undesirable impacts on the environment of the railway road area. The quality of the fruits is directly related with the elements of the soil, so understanding the element contents of soil in navel oranges garden in the vicinity of railway is meaningful to the security of agriculture products and ecological conditions in the areas surrounding the railways. As a favorite fruit, navel orange is widely planted around the railway in the south China, especially in Sichuan, Chongqing, Hubei, Jiangxi and Guizhou. The present paper studied the contents of Pb, Cd, Mn, Cu, Zn etc in the soil planting navel orange in the vicinity of Chengdu-Dazhou railway by AAS. The railway was built in 1997 and the research area was sited in Jintang county, Sichuan. The results showed that the contents of Pb and Mn in soil planting navel orange were significantly higher than those in the control soil, but the contents of Cd, Cu and Zn showed no significant difference.

  17. Lamb wave ultrasonic evaluation of welded AA2024 specimens at tensile static and fatigue testing

    NASA Astrophysics Data System (ADS)

    Burkov, M. V.; Byakov, A. V.; Shah, R. T.; Lyubutin, P. S.; Panin, S. V.

    2015-10-01

    The paper deals with the investigation of Lamb waves ultrasonic testing technique applied for evaluation of different stress-strain and damaged state of aluminum specimens at static and fatigue loading in order to develop a Structural Health Monitoring (SHM) approach. The experimental results of tensile testing of AA2024T3 specimens with welded joints are presented. Piezoelectric transducers used as actuators and sensors were adhesively bonded to the specimen's surface using two component epoxy. The set of static and cyclic tensile tests with two frequencies of acoustic testing (50 kHz and 335 kHz) were performed. The recorded signals were processed to calculate the maximum envelope in order to evaluate the changes of the stress-strain state of the specimen and its microstructure during static tension. The registered data are analyzed and discussed in terms of signal attenuation due to the formation of fatigue defects during cyclic loading. Understanding the relations between acoustic signal features and fatigue damages will provide us the ability to determine the damage state of the structure and its residual lifetime in order to design a robust SHM system.

  18. Characterization Of Flow Stress Of Different AA6082 Alloys By Means Of Hot Torsion Test

    SciTech Connect

    Donati, Lorenzo; El Mehtedi, Mohamad

    2011-05-04

    FEM simulations are become the most powerful tools in order to optimize the different aspects of the extrusion process and an accurate flow stress definition of the alloy is a prerequisite for a reliable effectiveness of the simulation. In the paper the determination of flow stress by means of hot torsion test is initially presented and discussed: the several approximations that are usually introduced in flow stress computation are described and computed for an AA6082 alloy in order to evidence the final effect on curves shapes. The procedure for regressing the parameters of the sinhyperbolic flow stress definition is described in detailed and applied to the described results. Then four different alloys, extracted by different casting batches but all namely belonging to the 6082 class, were hot torsion tested in comparable levels of temperature and strain rate up to specimen failure. The results are analyzed and discussed in order to understand if a mean flow stress behavior can be identified for the whole material class at the different tested conditions or if specific testing conditions (chemical composition of the alloy, specimen shape, etc) influence the materials properties to a higher degree.

  19. Evaluation of dynamic recrystallization behaviors in hot-extruded AA5083 through hot torsion tests

    NASA Astrophysics Data System (ADS)

    Son, Kwang-Tae; Lee, Ji-Woon; Jung, Taek-Kyun; Choi, Hyun-Jin; Kim, Sang-Wook; Kim, Shae K.; Yoon, Young-Ok; Hyun, Soong-Keun

    2017-01-01

    Hot torsion tests were carried out to evaluate the dynamic recrystallization (DRX) behaviors of hot-extruded AA5083 at various deformation conditions. Flow curves showed the peak followed by the flow softening to the steady-state or to the failure strain, indicating that the DRX occurred during deformation. The peak stress increased as the temperature decreased and the strain rate increased. Constitutive relationship and Zener-Hollomon ( Z) parameter were used to evaluate the DRX characteristics. Peak and steady-state stresses were generalized by the dimensionless parameter, Z/A, to reveal the DRX mechanism. The empirical relationship of the DRXed grain size with the deformation conditions was established, and decreased with increasing Z parameter. The relationship for the fraction of DRXed grains was established as a function of the effective strain at given deformation conditions from the experimental data. The Avrami relationship based on micro-hardness measurement was used to describe the DRX kinetics, and was fitted well with the observed DRX fraction.

  20. Description of plastic anisotropy in AA6063-T6 using the crystal plasticity finite element method

    NASA Astrophysics Data System (ADS)

    Dumoulin, S.; Engler, O.; Hopperstad, O. S.; Lademo, O. G.

    2012-07-01

    The crystal plasticity finite element method has been used in combination with crystallographic texture data to predict the plastic anisotropy of the extruded aluminium alloy AA6063 in temper T6. The results are compared with experimental data from tensile tests at different angles between the tensile and extrusion directions. Inverse modelling based on the tensile test in a reference direction is used to identify the parameters of the work-hardening model at slip system level. To investigate the influence of grain interactions, various discretizations of the grains are applied in the representative volume element modelled with finite elements. In addition, alternative homogenization schemes, such as the full-constraint Taylor and viscoplastic self-consistent methods, are used to model the behaviour of the polycrystal. It is found that the grain discretization and the homogenization scheme have only minor influence on the predicted plastic anisotropy. While the crystal plasticity-based methods all give reasonable predictions of the directional variations of flow stresses and plastic strain ratios measured experimentally, there are still significant deviations, indicating there are other sources to the plastic anisotropy than crystallographic texture.

  1. Pairing and recombination at meiosis of Brassica rapa (AA) x Brassica napus (AACC) hybrids.

    PubMed

    Leflon, M; Eber, F; Letanneur, J C; Chelysheva, L; Coriton, O; Huteau, V; Ryder, C D; Barker, G; Jenczewski, E; Chèvre, A M

    2006-11-01

    Interspecific crosses contribute significantly to plant evolution enabling gene exchanges between species. The efficiency of interspecific crosses depends on the similarity between the implicated genomes as high levels of genome similarity are required to ensure appropriate chromosome pairing and genetic recombination. Brassica napus (AACC) is an allopolyploid, resulting from natural hybridization between Brassica rapa (AA) and Brassica oleracea (CC), both being diploid species derived from a common ancestor. To study the relationships between genomes of these Brassica species, we have determined simultaneously the pairing and recombination pattern of A and C chromosomes during meiosis of AAC triploid hybrids, which result from the interspecific cross between natural B. napus and B. rapa. Different AAC triploid hybrids and their progenies have been analysed using cytogenetic, BAC-FISH, and molecular techniques. In 71% of the pollen mother cells, homologous A chromosomes paired regularly, and usually one chromosome of each pair was transmitted to the progeny. C chromosomes remained mainly univalent, but were involved in homoeologous pairing in 21.5% of the cells, and 13% of the transmitted C chromosomes were either recombined or broken. The rate of transmission of C chromosomes depended on the identity of the particular chromosome and on the way the hybrid was crossed, as the male or as the female parent, to B. napus or to B. rapa. Gene transfers in triploid hybrids are favoured between A genomes of B. rapa and B. napus, but also occur between A and C genomes though at lower rates.

  2. Prediction of Ductile Failure in the Stretch-Forming of AA2024 Sheets

    SciTech Connect

    Vallellano, C.; Guzman, C.; Garcia-Lomas, F. J.

    2007-05-17

    A number of ductile failure criteria are nowadays being used to predict the formability of aluminium alloy sheets. Generally speaking, integral criteria (e.g. those proposed by Cockcroft and Latham, Brozzo et al., Oyane et al Chaouadi et al., etc.) have been probed to work well when the principal strains are of opposite sign, i.e. in the left side of the Forming Limit Diagram (FLD). However, when tensile biaxial strains are present, as occurs in stretch-forming practice, their predictions are usually very poor and even non-conservatives. As an alternative, local criteria, such as the classical Tresca's and Bressan and Williams' criteria, have demonstrated a good capability to predict the failure in some automotive aluminum alloys under stretching. The present work analyses experimentally and numerically the failure in AA2024-T3 sheets subjected to biaxial stretching. A series of out-of-plane stretching tests have been simulated using ABAQUS. The experimental and the numerical FLD for different failure criteria are compared. The influence on the failure of the hydrostatic pressure and the normal stress to the fracture plane is also discussed.

  3. Computational Analysis of Material Flow During Friction Stir Welding of AA5059 Aluminum Alloys

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Arakere, G.; Pandurangan, B.; Ochterbeck, J. M.; Yen, C.-F.; Cheeseman, B. A.; Reynolds, A. P.; Sutton, M. A.

    2012-09-01

    Workpiece material flow and stirring/mixing during the friction stir welding (FSW) process are investigated computationally. Within the numerical model of the FSW process, the FSW tool is treated as a Lagrangian component while the workpiece material is treated as an Eulerian component. The employed coupled Eulerian/Lagrangian computational analysis of the welding process was of a two-way thermo-mechanical character (i.e., frictional-sliding/plastic-work dissipation is taken to act as a heat source in the thermal-energy balance equation) while temperature is allowed to affect mechanical aspects of the model through temperature-dependent material properties. The workpiece material (AA5059, solid-solution strengthened and strain-hardened aluminum alloy) is represented using a modified version of the classical Johnson-Cook model (within which the strain-hardening term is augmented to take into account for the effect of dynamic recrystallization) while the FSW tool material (AISI H13 tool steel) is modeled as an isotropic linear-elastic material. Within the analysis, the effects of some of the FSW key process parameters are investigated (e.g., weld pitch, tool tilt-angle, and the tool pin-size). The results pertaining to the material flow during FSW are compared with their experimental counterparts. It is found that, for the most part, experimentally observed material-flow characteristics are reproduced within the current FSW-process model.

  4. Mechanical properties and structure of friction stir welds of rolled Zr-modified AA5083 alloy

    NASA Astrophysics Data System (ADS)

    Malopheyev, S.; Mironov, S.; Kaibyshev, R.

    2016-11-01

    Microstructure and mechanical properties of friction stir welds of Zr-modified AA5083 aluminum sheets were studied. The sheets were produced by cold or hot rolling with a total reduction of 80%. In both rolled conditions, the average high angle boundary spacing was 17-18 µm. The density of free dislocations was ˜5.6 × 1013 and ˜3.5 × 1014 m-2 in hot rolled and cold rolled conditions, respectively. The volume fraction of incoherent Al6Mn dispersoids with an average diameter of ˜25 nm was measured to be ˜0.076%. Defect-free welds were produced by double-side friction stir welding (FSW). Friction stir welding led to the formation of fully recrystallized microstructures with the average grain size about 2.5 µm and low dislocation density in the stir zone in both conditions. The average size and volume fraction of Al6Mn particles increased to ˜25 nm and ˜0.1%, respectively. The joint efficiency of the friction stir welds for ultimate tensile strength was found to be 74 and 94% in the cold-rolled and hot-rolled preprocessed material conditions. The relatively low weld strength was attributed to the elimination of dislocation substructure strengthening during FSW.

  5. [Determination of trace barium in soil and sediment by Zeeman graphite AAS with coated graphite tube].

    PubMed

    Ji, Hai-Bing; Liu, Jin-Song; Pang, Xiao-Lu

    2007-11-01

    The sample was decomposed by HNO3-HF-HClO4. Using a tungsten-coated graphite tube, trace barium in soil and sediment was determined by Zeeman graphite AAS. To avoid producing carbide, the graphite tube was coated with tungsten. Tungsten and carbon in the surface layer of graphite tube became tungsten carbide. Tungsten carbide prevented barium and carbon from forming barium carbide, which in turn not only led to a long service life for the tube, but also increased greatly the sensitivity and precision of the determination Ba. Tungsten carbide belongs to internal filled type and can give reduction environment. To some extent, the common interfering elements co-existing in the soil and sediment had little chance to form oxides to interfere the determination of Ba in the atomization period. The method was easy and sensitive. The detection limit of Ba was 4.2 x 10(-10) g x g(-1). The relative standard deviation (RSD) was in the range of 2.0%-6.5% (n = 4). The relative deviations from the certificated values of standard soils were under 5%.

  6. Design of an airframe agnostic roll-on/roll-off (AA-RORO) sensor platform

    NASA Astrophysics Data System (ADS)

    Sparks, Bruce; Wowczuk, Zenovy S.; Harrison, A. Jay

    2009-05-01

    The US military has recently taken tactical steps to increase its ISR capabilities to support military operations. Due to the dynamic capabilities of the terrorist threat, there is a need for a payload- and airframe-agnostic, rapid-deployment sensor system that can be used on multiple airframes for in-theater missions and for the test and evaluation of sensors prior to fielding. This "plug-and-play" system, based upon the Oculus Sensor Deployment System technology, uses a system-of-systems approach to modularize the base platform, thereby allowing the system to conform to aircraft such as the C-130, C-27, V-22, CH-47, CH-53 and CASA-235 without any modification to the airframe itself. This type of system can be used as (1) a versatile, cost-effective test and evaluation platform for current and developmental sensors as well as (2) an in-theater ISR asset that can be used on readily available airframes at a particular location. This paper illustrates the CONUS and OCONUS mission potential of this multi-airframe system and outlines the novel design characteristics that the Airframe Agnostic Roll-on/Roll-off (AA-RORO) sensor platform incorporates to make it the most versatile, rapid-deployment sensor platform available to support near-term U.S. military operations. The system concept was developed with the support of and input from multiple military agencies and the respective branches they represent.

  7. Determination of chromium and nickel in commercial foam bath products by ETA-AAS.

    PubMed

    Ciaralli, L; Giordano, R; Cassina, S; Sepe, A; Costantini, S

    1996-01-01

    The presence of some inorganic elements, such as Ni and Cr in cosmetic products could be responsible for some skin diseases, such as allergic dermatitis. This paper deals with the determination of these two elements in commercial samples of foam bath products by means of the ETA-AAS technique. Four different analytical procedures for sample digestion are evaluated and discussed. Results indicated that the high-pressure microwave digestion is the best procedure for treatment of the complex matrices considered in the study. Chromium values were in the range of 22-199 micrograms/kg, whereas those of nickel fell within the range 26-287 micrograms/kg. The detection limit (3 sigma) of the whole procedure was 3 micrograms/kg for Cr and 15 micrograms/kg for Ni. The analytical data demonstrated that both Ni and Cr were present in all the samples at very low concentrations, and that foam bath products are a relatively minor source of exposure to these elements.

  8. Spatial and Temporal Characteristics of Propagating Deformation Bands in AA5182 Alloy at Room Temperature

    NASA Astrophysics Data System (ADS)

    de Codes, R. Nogueira; Hopperstad, O. S.; Engler, O.; Lademo, O.-G.; Embury, J. D.; Benallal, A.

    2011-11-01

    The spatial and temporal characteristics of propagating deformation bands in the Al-Mg alloy AA5182 in O temper were studied experimentally at room temperature. Tensile tests were carried out on flat specimens at strain rates in the range from 10-5 to 10-1 s-1. Digital image correlation (DIC) and digital infrared thermography (DIT) were applied to monitor the propagating bands. It was found that the material exhibits a sharp yield point, and Lüders bands were seen at all the strain rates. Jerky flow took place all along the Lüders plateau. It thus seems that the Portevin-Le Chatelier (PLC) effect starts at incipient yielding and that there is no critical strain. At the end of the Lüders plateau, PLC bands immediately started to propagate back and forth along the gage section of the specimen. The work hardening of the material decreased consistently with increasing strain rate, while the flow stress on the Lüders plateau was rather unaffected by the strain rate. This indicates that the dynamic strain aging (DSA) mainly affects the strength of the interaction between mobile and forest dislocations. The strain to necking was found to decrease gradually with strain rate for this alloy, which is consistent with the lower work-hardening rate at the higher strain rates.

  9. Molecular characterization of subgenotype A1 (subgroup Aa) of hepatitis B virus.

    PubMed

    Kramvis, Anna; Kew, Michael C

    2007-07-01

    Subgenotypes of hepatitis B virus (HBV) were first recognized after a unique segment of genotype A was identified when sequencing the preS2/S region of southern African HBV isolates. Originally named subgroup A', subsequently called subgroup Aa (for Africa) or subgenotype A1, this subgenotype is found in South Africa, Malawi, Uganda, Tanzania, Somalia, Yemen, India, Nepal, the Philippines and Brazil. The relatively higher mean nucleotide divergence of subgenotype A1 suggests that it has been endemic and has a long evolutionary history in the populations where it prevails. Distinctive sequence characteristics could account for the high hepatitis B e-antigen (HBeAg) negativity and low HBV DNA levels in carriers of this subgenotype. Substitutions or mutations can reduce HBeAg expression at three levels: (i) 1762T1764A atthe transcriptional level; (ii) substitutions at nt 1809-1812 at the translational level; and (iii) 1862T at the post-translational level. Co-existence of 1762T1764A and nt 1809-1812 mutations reduces HBeAg expression in an additive manner. In addition, subgenotype A1 has unique sequence alterations in the transcriptional regulatory elements and the polymerase coding region. The distinct sequence characteristics of subgenotype A1 may contribute to the 4.5-fold increased risk of heptocellular carcinoma in HBV carriers infected with genotype A, which is entirely attributable to subgenotype A1.

  10. Goos-Hänchen shifts in AA-stacked bilayer graphene superlattices

    NASA Astrophysics Data System (ADS)

    Zahidi, Youness; Redouani, Ilham; Jellal, Ahmed

    2016-07-01

    The quantum Goos-Hänchen shifts of the transmitted electron beam through an AA-stacked bilayer graphene superlattices are investigated. We found that the band structures of graphene superlattices can have more than one Dirac point, their locations do not depend on the number of barriers. It was revealed that any n-barrier structure is perfectly transparent at normal incidence around the Dirac points created in the superlattices. We showed that the Goos-Hänchen shifts display sharp peaks inside the transmission gap around two Dirac points (E =VB + τ, E =VW + τ), which are equal to those of transmission resonances. The obtained Goos-Hänchen shifts are exhibiting negative as well as positive behaviors and strongly depending on the location of Dirac points. It is observed that the maximum absolute values of the shifts increase as long as the number of barriers is increased. Our analysis is done by considering four cases: single, double barriers, superlattices without and with defect.

  11. Tensile and Creep Behavior of Extruded AA6063/SiC{sub p} Al MMCs

    SciTech Connect

    Khalifa, Tarek A.; Mahmoud, Tamer S.

    2010-03-01

    Composites of AA6063 Al alloy reinforced with SiC particles (SiC{sub p}) were prepared by the vortex method. Hot extrusion was carried out for the as cast composites with a reduction in area of 25%. Tensile and creep behavior of as-cast and extruded composites were studied at elevated temperatures. Tensile tests carried out at room temperature showed that for the as-cast composites, the addition of SiC{sub p} up to 10% by weight improves the strength but reduces ductility. Further addition of SiC{sub p} reduces the strength and ductility of the composites. At 150 and 300 deg. C the matrix alloy exhibits higher strength than the composites. Extrusion generally raised the strength of the composites at both room and elevated temperatures. Time rupture creep tests carried out at 300 deg. C showed that the composites exhibit higher creep resistance as compared to the matrix alloy except at relatively low stresses where the matrix has a better creep resistance. Extrusion improved the resistance of composites to creep rupture.

  12. The optimized mechanical properties of the new aluminum alloy AA 6069

    SciTech Connect

    Bergsma, S.C.; Kassner, M.E.; Li, X.; Delos-Reyes, M.A.; Hayes, T.A.

    1996-02-01

    AA 6069, a new aluminum alloy, has been developed for application in hot and cold extrusion and forging. It contains {approximately}2 Mg + Si, {approximately}1% Cu, 0.2% Cr, and 0.1% V. Nominal T6 properties of the ingot without hot or cold deformation are 415 MPa (60 ksi) ultimate tensile strength (UTS), 380 MPa (55 ksi) yield strength, and 12% elongation. Properties after hot and cold extrusion in the T6 condition rate from 380 to 490 MPa (55 to 71 ksi) UTS, 345 to 450 MPa (50 to 65 ksi) yield strength, and 10 to 22% elongation. This alloy also has favorable fatigue and corrosion-fatigue properties due to a combination of composition, high solidification rate, controlled homogenization, thermal and mechanical processing, and T6 practice. Current development applications include cold-impact air-bag components, high-pressure cylinders, and automotive suspension and drive-train parts. Unlike alloys 2024-T3 and 7129-T6, of comparable strength, diluted 6069 is scrap compatible with many other 5xxx and 6xxx alloys.

  13. AAS Publishing: What Can WorldWide Telescope Do for You?

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    During the 227th American Astronomical Society meeting last week in Kissimmee, the AAS announced the exciting news that it will become the new institutional home of Microsofts WorldWide Telescope (WWT) astronomy software.WWT is a scriptable and interactive way of browsing the multi-wavelength sky as it is seen from Earth, and the universe as we would travel within it. WWT can be run either as a desktop app or from within an internet browser. And of interest to researchers especially its an incredibly useful way to visualize and contextualize astronomical data.What does WWTs transition to the AAS as its new host mean? WWT was open-sourced by Microsoft Research last year, and hosting by the AAS will permit broad community involvement in the form of contribution of both code and guidance in WWTs further development.All of this begs the question: why might YOU want to use WWT? That depends on whether your goal is to use it for research, education, or just for fun.WWT for ResearchIfyou thought WWT was just for education and outreach, think again! Here are just a few things you can do with WWT to advance your astronomical research1:1) Put surveys into context, on top of more than 40 different all-sky images, spanning the electromagnetic spectrum.2) Perform literature searches from the sky.3) Compare images and catalogs at different wavelengths, on-the-fly in seconds.4) Show your own online data to the world, in an API that allows users to see it on the sky in their browsers.5) Communicate to colleagues and learners about the sky using interactive tours of your data and ideas.An example of WWT used to perform astronomy research is the recently highlighted work on the bones of the Milky Way, in which the authors used WWT to overlay multiple data sets and visually identify and then search for infrared dark clouds along the predicted positions of Milky Way spiral arms.An example of WWT used to communicate research is given in this paper, wherein a link in the caption of a

  14. Fatigue damage characterization using surface acoustic wave nonlinearity in aluminum alloy AA7175-T7351

    NASA Astrophysics Data System (ADS)

    Jaya Rao, V. V. S.; Kannan, Elankumaran; Prakash, Raghu V.; Balasubramaniam, Krishnan

    2008-12-01

    Nonlinear ultrasonic (NLU) harmonic generation system was used to characterize the fatigue damage in a flat hour-glass, high strength Al-Cu-Zn-Mg alloy, AA7175-T7351 specimens. Experiments were carried out to introduce controlled levels of fatigue damage under constant amplitude loading to determine the NLU response using surface acoustic wave (or Rayleigh mode) at regular intervals of fatigue life. The NLU parameter (A2/A12) plotted as a function of percentage of fatigue life shows two peaks for all the samples tested, independent of the amplitude of fatigue loading. The first peak appeared between 40%-50% of fatigue life and the second peak between 80%-90% of fatigue life. Among the two flat surfaces of the specimen, a higher nonlinearity response was observed on the surface which had the first crack initiation. The appearance of two peaks in the nonlinear response during fatigue damage progression is explained based on the dislocation dynamics and dislocation-crack interaction present in the specimens during the fatigue process.

  15. Development and characterization of an ascorbate oxidase-based sensor-biosensor system for telemetric detection of AA and antioxidant capacity in fresh orange juice.

    PubMed

    Barberis, Antonio; Spissu, Ylenia; Bazzu, Gianfranco; Fadda, Angela; Azara, Emanuela; Sanna, Daniele; Schirra, Mario; Serra, Pier Andrea

    2014-09-02

    A new carbon ascorbate oxidase-based sensor-biosensor system (SB) was coupled to a dual-channel telemetric device for online simultaneous electrochemical detection of ascorbic acid (AA) and antioxidant capacity in Hamlin, Sanguinello, and Moro orange varieties. The electrocatalytic performances of the SB were investigated by cyclic voltammetry and amperometric techniques. The phenol composition of orange juice of each variety, and the cyclic voltammetries of the most represented phenols, were provided. The in vitro calibrations were performed in PBS (pH 5.6), applying a constant potential of +500 mV. A standard mixture of phenols, based on orange juice composition, was used as reference material for studying SB behavior. SB works at an applied potential of +500 mV, in a concentration range comprised between the LOD 0.26 μM and 20 μM. In this concentration range, limiting the data acquisition time to 2 min, the problems of electrode passivation due to phenols polymerization were overcome. AA calibration showed that the biosensor registered statistically lower currents than the sensor since the enzyme oxidized AA before it reached the electrode surface. Standard mixture calibration showed that currents registered by sensor and biosensor did not statistically differ. The difference between sensor and biosensor AA registered currents was used to calculate an AA selectivity index and, consequently, to determine the AA content and the antioxidant capacity in the juices. The novelty of the SB is its ability to distinguish between AA and phenols contribution to antioxidant capacity. The obtained results were in accordance with reference methods.

  16. AaCAT1 of the yellow fever mosquito, Aedes aegypti: a novel histidine-specific amino acid transporter from the SLC7 family.

    PubMed

    Hansen, Immo A; Boudko, Dmitri Y; Shiao, Shin-Hong; Voronov, Dmitri A; Meleshkevitch, Ella A; Drake, Lisa L; Aguirre, Sarah E; Fox, Jeffrey M; Attardo, Geoffrey M; Raikhel, Alexander S

    2011-03-25

    Insect yolk protein precursor gene expression is regulated by nutritional and endocrine signals. A surge of amino acids in the hemolymph of blood-fed female mosquitoes activates a nutrient signaling system in the fat bodies, which subsequently derepresses yolk protein precursor genes and makes them responsive to activation by steroid hormones. Orphan transporters of the SLC7 family were identified as essential upstream components of the nutrient signaling system in the fat body of fruit flies and the yellow fever mosquito, Aedes aegypti. However, the transport function of these proteins was unknown. We report expression and functional characterization of AaCAT1, cloned from the fat body of A. aegypti. Expression of AaCAT1 transcript and protein undergoes dynamic changes during postembryonic development of the mosquito. Transcript expression was especially high in the third and fourth larval stages; however, the AaCAT1 protein was detected only in pupa and adult stages. Functional expression and analysis of AaCAT1 in Xenopus oocytes revealed that it acts as a sodium-independent cationic amino acid transporter, with unique selectivity to L-histidine at neutral pH (K(0.5)(L-His) = 0.34 ± 0.07 mM, pH 7.2). Acidification to pH 6.2 dramatically increases AaCAT1-specific His(+)-induced current. RNAi-mediated silencing of AaCAT1 reduces egg yield of subsequent ovipositions. Our data show that AaCAT1 has notable differences in its transport mechanism when compared with related mammalian cationic amino acid transporters. It may execute histidine-specific transport and signaling in mosquito tissues.

  17. A double-blind, randomized, placebo-controlled, active reference study of Lu AA21004 in patients with major depressive disorder.

    PubMed

    Alvarez, Enric; Perez, Victor; Dragheim, Marianne; Loft, Henrik; Artigas, Francesc

    2012-06-01

    The efficacy, safety, and tolerability of Lu AA21004 vs. placebo using venlafaxine XR as active reference in patients with DSM-IV-TR major depressive disorder (MDD) were evaluated. Lu AA21004 is a novel antidepressant that is a 5-HT3 and 5-HT7 receptor antagonist, 5-HT1A receptor agonist, 5-HT1B receptor partial agonist and inhibitor of the 5-HT transporter in recombinant cell lines. In this 6-wk, multi-site study, 429 patients were randomly assigned (1:1:1:1) to 5 or 10 mg Lu AA21004, placebo or 225 mg venlafaxine XR. All patients had a baseline Montgomery-Åsberg Depression Rating Scale (MADRS) total score ≥ 30. The primary efficacy analysis was based on the MADRS total score adjusting for multiplicity using a hierarchical testing procedure starting with the highest dose vs. placebo. Lu AA21004 was statistically significantly superior to placebo (n=105) in mean change from baseline in MADRS total score at week 6 (p<0.0001, last observation carried forward), with a mean treatment difference vs. placebo of 5.9 (5 mg, n=108), and 5.7 (10 mg, n=100) points. Venlafaxine XR (n=112) was also significantly superior to placebo at week 6 (p<0.0001). In total, 30 patients withdrew due to adverse events (AEs)--placebo: four (4%); 5 mg Lu AA21004: three (3%); 10 mg Lu AA21004: seven (7%); and venlafaxine: 16 (14%). The most common AEs were nausea, headache, hyperhidrosis, and dry mouth. No clinically relevant changes over time were seen in the clinical laboratory results, vital signs, weight, or ECG parameters. In this study, treatment with 5 mg and 10 mg Lu AA21004 for 6 wk was efficacious and well tolerated in patients with MDD.

  18. Protective efficacy of Anopheles minimus CYP6P7 and CYP6AA3 against cytotoxicity of pyrethroid insecticides in Spodoptera frugiperda (Sf9) insect cells.

    PubMed

    Duangkaew, P; Kaewpa, D; Rongnoparut, P

    2011-08-01

    Cytochrome P450 monooxygenases (P450s) are enzymes known to metabolize a wide variety of compounds including insecticides. Their overexpression leading to enhanced insecticide detoxification could result in insecticide resistance in insects. The increased mRNA expression of two P450 genes, CYP6P7 and CYP6AA3, has been previously observed in laboratory-selected deltamethrin-resistant Anopheles minimus, a major malaria vector in Southeast Asia, suggesting their role in detoxification of pyrethroids. In this study CYP6P7 and CYP6AA3 were expressed in insect Spodoptera frugiperda (Sf9) cells via baculovirusdirected expression system. Insecticide detoxification capabilities of Sf9 cells with and without expression of CYP6P7 or CYP6AA3 were evaluated using 3-(4,5-dimethyl-thiazol-2- yl)-2,5-diphenyltetrazolium bromide (MTT) assays. The results revealed that CYP6P7- or CYP6AA3-expressing cells showed significantly higher cytoprotective capability than parental Sf9 cells against cytotoxicity of pyrethroids including permethrin, cypermethrin and deltamethrin. Such cytoprotective effect was not observed for bioallethrin (pyrethroid), chlorpyrifos (organophosphate) and propoxur (carbamate). Moreover, expression of CYP6AA3, but not CYP6P7, could protect cells against λ-cyhalothrin cytotoxicity. In MTT assays upon co-incubation with piperonyl butoxide (P450 inhibitor), cytoprotective ability of CYP6P7 and CYP6AA3 against deltamethrin was diminished, implying that pyrethroid detoxification was due to activities of P450 enzymes. Insecticide detoxification capabilities of CYP6P7 and CYP6AA3 observed from MTT assays were correlated to their pyrethroid metabolizing activities observed from in vitro reconstitution enzymatic assays. Thus MTT assays using cells expressing P450 enzymes of interest could be primarily used to determine detoxification activities of enzymes against cytotoxic insecticides.

  19. Agrotis segetum midgut putative receptor of Bacillus thuringiensis vegetative insecticidal protein Vip3Aa16 differs from that of Cry1Ac toxin.

    PubMed

    Ben Hamadou-Charfi, Dorra; Boukedi, Hanen; Abdelkefi-Mesrati, Lobna; Tounsi, Slim; Jaoua, Samir

    2013-10-01

    Considering the fact that Agrotis segetum is one of the most pathogenic insects to vegetables and cereals in the world, particularly in Africa, the mode of action of Vip3Aa16 of Bacillus thuringiensis BUPM95 and Cry1Ac of the recombinant strain BNS3Cry-(pHTcry1Ac) has been examined in this crop pest. A. segetum proteases activated the Vip3Aa16 protoxin (90kDa) yielding three bands of about 62, 45, 22kDa and the activated form of the toxin was active against this pest with an LC50 of about 86ng/cm(2). To be active against A. segetum, Cry1Ac protoxin was activated to three close bands of about 60-65kDa. Homologous and heterologous competition binding experiments demonstrated that Vip3Aa16 bound specifically to brush border membrane vesicles (BBMV) prepared from A. segetum midgut and that it does not inhibit the binding of Cry1Ac. Moreover, BBMV protein blotting experiments showed that the receptor of Vip3Aa16 toxin in A. segetum midgut differs from that of Cry1Ac. In fact, the latter binds to a 120kDa protein whereas the Vip3Aa16 binds to a 65kDa putative receptor. The midgut histopathology of Vip3Aa16 fed larvae showed vacuolization of the cytoplasm, brush border membrane lysis, vesicle formation in the goblet cells and disintegration of the apical membrane. The distinct binding properties and the unique protein sequence of Vip3Aa16 support its use as a novel insecticidal agent to control the crop pest A. segetum.

  20. A Coordinated X-Ray and Optical Campaign of the Nearest Massive Eclipsing Binary, Delta Orionis Aa. I. Overview of the X-Ray Spectrum

    NASA Technical Reports Server (NTRS)

    Corcoran, M. F.; Nicholas, J. S.; Pablo, H.; Shenar, T.; Pollock, A. M. T.; Waldron, W. L.; Moffat, A. F. J.; Richardson, N. D.; Russell, C. M. P.; Hamaguchi, K.; Leutenegger, M.; Gull, T. R.; Iping, R. C.

    2015-01-01

    We present an overview of four deep phase-constrained Chandra HETGS X-ray observations of Delta Ori A. Delta Ori A is actually a triple system that includes the nearest massive eclipsing spectroscopic binary, Delta Ori Aa, the only such object that can be observed with little phase-smearing with the Chandra gratings. Since the fainter star, Delta Ori Aa2, has a much lower X-ray luminosity than the brighter primary (Delta Ori Aa1), Delta Ori Aa provides a unique system with which to test the spatial distribution of the X-ray emitting gas around Delta Ori Aa1 via occultation by the photosphere of, and wind cavity around, the X-ray dark secondary. Here we discuss the X-ray spectrum and X-ray line profiles for the combined observation, having an exposure time of nearly 500 ks and covering nearly the entire binary orbit. The companion papers discuss the X-ray variability seen in the Chandra spectra, present new space-based photometry and ground-based radial velocities obtained simultaneously with the X-ray data to better constrain the system parameters, and model the effects of X-rays on the optical and UV spectra. We find that the X-ray emission is dominated by embedded wind shock emission from star Aa1, with little contribution from the tertiary star Ab or the shocked gas produced by the collision of the wind of Aa1 against the surface of Aa2. We find a similar temperature distribution to previous X-ray spectrum analyses. We also show that the line half-widths are about 0.3-0.5 times the terminal velocity of the wind of star Aa1. We find a strong anti-correlation between line widths and the line excitation energy, which suggests that longer-wavelength, lower-temperature lines form farther out in the wind. Our analysis also indicates that the ratio of the intensities of the strong and weak lines of Fe XVII and Ne X are inconsistent with model predictions, which may be an effect of resonance scattering.