Andere Lander, Andere Sitten!

ERIC Educational Resources Information Center

Kirchner, Martha

A self-instructional unit on eating habits and customs in Germany is presented for the high school student studying second-year German. Notes to the teacher outline general goals of the unit, specific objectives, additional activities, equipment, and student evaluation. The general goals are: to be able to eat a meal in Germany without offending…

ANDERS: future of concrete bridge deck evaluation and rehabilitation

NASA Astrophysics Data System (ADS)

Gucunski, Nenad; Moon, Franklin

2011-04-01

The Automated Nondestructive Evaluation and Rehabilitation System (ANDERS) aims to provide a uniquely comprehensive tool that will transform the manner in which bridge decks are assessed and rehabilitated. It is going to be achieved through: 1) much higher evaluation detail and comprehensiveness of detection at an early stage deterioration, 2) comprehensive condition and structural assessment at all stages of deterioration, and 3) integrated assessment and rehabilitation that will be minimally invasive, rapid and cost effective. ANDERS is composed of four systems. that merge novel imaging and NDE techniques, together with novel intervention approaches to arrest the deterioration processes. These technologies are incorporated within a series of human-operated and robotic vehicles. To perform assessments, ANDERS will be equipped with two complimentary nondestructive approaches. The first, Multi-Modal Nondestructive Evaluation (MM-NDE) System aims to identify and characterize localized deterioration with a high degree of resolution. The second, Global Structural Assessment (GSA) System aims to capture global structural characteristics and identify any appreciable effects of deterioration on a bridge structure. Output from these two approaches will be merged through a novel Automated Structural Identification (Auto St-Id) approach that will construct, calibrate, and utilize simulation models to assess overall structural vulnerability and capacity. These three systems comprise the assessment suite of ANDERS and will directly inform the Nondestructive Rehabilitation (NDR) System. The NDR System leverages robotics for the precision and rapid delivery of novel materials capable of halting the early-stage deterioration identified.

Saturn Apollo Program

NASA Image and Video Library

1967-09-09

This is the official NASA portrait of astronaut William Anders. Anders was commissioned in the air Force after graduation from the Naval Academy and served as a fighter pilot in all-weather interception squadrons of the Air Defense Command. Later he was responsible for technical management of nuclear power reactor shielding and radiation effects programs while at the Air Force Weapons Laboratory in New Mexico. In 1964, Anders was selected by the National Aeronautics and Space Administration (NASA) as an astronaut with responsibilities for dosimetry, radiation effects and environmental controls. He was backup pilot for the Gemini XI, Apollo 11 flights, and served as lunar module (LM) pilot for Apollo 8, the first lunar orbit mission in December 1968. He has logged more than 6,000 hours flying time.

Screening for DSM-IV-TR Cognitive Disorder NOS in Parkinson’s disease using the Mattis Dementia Rating Scale

PubMed Central

Pontone, Gregory M.; Palanci, Justin; Williams, James R.; Bassett, Susan Spear

2012-01-01

Objective This study explores the utility of the Mattis Dementia Rating Scale (MDRS) as a screening tool for the Diagnostic and Statistical Manual for Mental Disorders 4th edition (DSM-IV-TR) diagnosis Cognitive Disorder Not Otherwise Specified in Parkinson’s disease(PD). Methods 125 individuals with PD were diagnosed using DSM-IV-TR criteria for Cognitive Disorder NOS and dementia. Receiver operating characteristics tested the discriminant validity of the MDRS, with the clinician’s diagnosis serving as the gold standard. Results The MDRS ROC curve to discriminate subjects with Cognitive Disorder NOS from non-demented subjects had an AUC of 0.59 (std. err.= 0.08, 95% CI: 0.43–0.74). Conclusions The MDRS is not effective for identifying PD patients with Cognitive Disorder NOS without dementia. PMID:22628158

Breakdown of the Wigner-Mattis theorem in semiconductor carbon-nanotube quantum dots

NASA Astrophysics Data System (ADS)

Rontani, Massimo; Secchi, Andrea; Manghi, Franca

2009-03-01

The Wigner-Mattis theorem states the ground state of two bound electrons, in the absence of the magnetic field, is always a spin-singlet. We predict the opposite result --a triplet- for two electrons in a quantum dot defined in a semiconductor carbon nanotube. The claim is supported by extensive many-body calculations based on the accurate configuration interaction code DONRODRIGO (www.s3.infm.t/donrodrigo). The crux of the matter is the peculiar two-valley structure of low-energy states, which encodes a pseudo-spin degree of freedom. The spin polarization of the ground state corresponds to a pseudo-spin singlet, which is selected by the inter-valley short-range Coulomb interaction. Single-electron excitation spectra and STM wave function images may validate this scenario, as shown by our numerical simulations.

Designing Graphic Presentations from First Principles

DTIC Science & Technology

1998-01-01

Khanna, Rahul Asthana, Pascale Fung, and Joanna Sadowska. Others, once near but now far, included: Ivelina Zlateva, Robert Chang, Anna Herreras , John...For example, Roth & Mattis (1990) propose characterizing data in terms of cardinality , coverage and uniqueness. Cardinality allows data to be

Computation and Modeling of Insect Flight

DTIC Science & Technology

2005-08-23

Andersen, U. Pesavento , and Z. J. Wang, J. Fluid Mech., 2005. A. Andersen, U. Pesavento , and Z. J. Wang, J. Fluid Mech., 2005. U, Pasavento and Z. J...Wang (P.I.) "* Umberto Pesavento , PhD Physics (2005), Cornell University "* Anders Andersen, 2002-2005, Postdoctoral Fellow "* Sheng Xu, 2003-2006...press. 3. Anders Andersen, Umberto Pesavento , and Z. Jane Wang, ’Unsteady Aerodynamics of Fluttering and Tumbling Plates’, Journal of Fluid Mechanics

Apollo 8 Astronaut Anders Suits Up For Countdown Demonstration Test

NASA Technical Reports Server (NTRS)

1968-01-01

Apollo 8 astronaut William Anders, Lunar Module (LM) pilot, is suited up for the Apollo 8 mission countdown demonstration test. The first manned Apollo mission launched aboard the Saturn V and first manned Apollo craft to enter lunar orbit, the SA-503, Apollo 8 mission lift off occurred on December 21, 1968 and returned safely to Earth on December 27, 1968. Aboard were Anders and fellow astronauts James Lovell, Command Module (CM) pilot; and Frank Borman, commander. The mission achieved operational experience and tested the Apollo command module systems, including communications, tracking, and life-support, in cis-lunar space and lunar orbit, and allowed evaluation of crew performance on a lunar orbiting mission. The crew photographed the lunar surface, both far side and near side, obtaining information on topography and landmarks as well as other scientific information necessary for future Apollo landings. All systems operated within allowable parameters and all objectives of the mission were achieved.

Apollo 8 Astronaut William Anders On Phone With President Johnson

NASA Technical Reports Server (NTRS)

1968-01-01

Apollo 8 Astronaut William Anders, Lunar Module (LM) pilot of the first manned Saturn V space flight into Lunar orbit, accepted a phone call from the U.S. President Lyndon B. Johnson prior to launch. Anders, along with astronauts James Lovell, Command Module (CM) pilot, and Frank Borman, commander, launched aboard the Apollo 8 mission on December 21, 1968 and returned safely to Earth on December 27, 1968. The mission achieved operational experience and tested the Apollo command module systems, including communications, tracking, and life-support, in cis-lunar space and lunar orbit, and allowed evaluation of crew performance on a lunar orbiting mission. The crew photographed the lunar surface, both far side and near side, obtaining information on topography and landmarks as well as other scientific information necessary for future Apollo landings. All systems operated within allowable parameters and all objectives of the mission were achieved.

High efficiency transformation of banana [Musa acuminata L. cv. Matti (AA)] for enhanced tolerance to salt and drought stress through overexpression of a peanut salinity-induced pathogenesis-related class 10 protein.

PubMed

Rustagi, Anjana; Jain, Shalu; Kumar, Deepak; Shekhar, Shashi; Jain, Mukesh; Bhat, Vishnu; Sarin, Neera Bhalla

2015-01-01

Bananas and plantains (Musa spp. L.) are important subsistence crops and premium export commodity in several countries, and susceptible to a wide range of environmental and biotic stress conditions. Here, we report efficient, rapid, and reproducible Agrobacterium-mediated transformation and regeneration of an Indian niche cultivar of banana [M. acuminata cv. Matti (AA)]. Apical meristem-derived highly proliferative multiple shoot clump (MSC) explants were transformed with the Agrobacterium strain EHA105 harboring a binary vector pCAMBIA-1301 carrying hptII and uidA. Sequential agro-infiltration (10 min, 400 mmHg), infection (additional 35 min, Agrobacterium density A 600 = 0.8) and co-cultivation (18 h) regimen in 100 µM acetosyringone containing liquid medium were critical factors yielding high transformation efficiency (~81 %) corroborated by transient GUS expression assay. Stable transgenic events were recovered following two cycles of meristem initiation and selection on hygromycin containing medium. Histochemical GUS assay in several tissues of transgenic plants and molecular analyses confirmed stable integration and expression of transgene. The protocol described here allowed recovery of well-established putative transgenic plantlets in as little as 5 months. The transgenic banana plants could be readily acclimatized under greenhouse conditions, and were phenotypically similar to the wild-type untransformed control plants (WT). Transgenic plants overexpressing Salinity-Induced Pathogenesis-Related class 10 protein gene from Arachis hypogaea (AhSIPR10) in banana cv. Matti (AA) showed better photosynthetic efficiency and less membrane damage (P < 0.05) in the presence of NaCl and mannitol in comparison to WT plants suggesting the role of AhSIPR10 in better tolerance of salt stress and drought conditions.

Dual exposure view of exterior and interior of Apollo Mission simulator

NASA Image and Video Library

1967-08-01

S67-50585 (1967) --- This is an intentional double exposure showing the Apollo Mission Simulator in the Mission Simulation and Training Facility, Building 5 at the Manned Spacecraft Center. In the exterior view astronauts William A. Anders, Michael Collins, and Frank Borman (reading from top of stairs) are about to enter the simulator. The interior view shows the three astronauts in the simulator. They are (left to right) Borman, Collins, and Anders. Photo credit: NASA

Tanker Fuel Efficiency: Saving Through Receiver Fuel Planning

DTIC Science & Technology

2014-06-13

engage your weapon.” General James Mattis , 2003 Conclusions The current planning and execution of air refueling missions are costing the DOD...fuel cells, and bio fuels are being explored by scientists and engineers working to reduce the United States’ dependency on foreign oil (Harmon

A resolution honoring the extraordinary and courageous life of Mattie Stepanek.

THOMAS, 113th Congress

Sen. Mikulski, Barbara A. [D-MD

2014-07-21

Senate - 07/21/2014 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

Removal of graffiti paintings from the Mansion de Mattis site in Corato (Bari), Italy: Laser deveiling or complete cleaning?

NASA Astrophysics Data System (ADS)

Daurelio, G.; Andriani, E. S.; Albanese, A.; Catalano, I. M.; Teseo, G.; Marano, D.

2008-10-01

Nowadays one the main problem of stone monuments conservation is not only the natural environment deterioration but the defaced, in particular esthetic, due to graffiti. This paper presents the different stages of the cleaning graffiti research: the laboratory study phase, in which the aims were to investigate the laser cleaning effect on substrate and testing user-friendly and efficient solutions for in situ application; the application phase in which the study results were applied in the restoration of Palazzo de Mattis facade. The graffiti cleaning were carried out by using a Q-Switch Nd:YAG laser source (λ=1064 nm with pulse duration, t=8 ns, f=2 to 20 Hz, energy per impulse up to 280 mJ) in dry, wet and Very wet modes adopting the Daurelio technique n.1 (blade spot laser). The Q-Switch Nd:Yag laser source has demonstrated to be the most suitable for a fully or, according to new restoring theory, "de veiling" graffiti ablation.

Physical and Moral Courage: An Essential Personal Attribute of a Successful Theater Strategic Commander

DTIC Science & Technology

2008-10-31

Emerson. Mission With LeMay. Garden City, NY: Doubleday, 1965: 13-14. 37 Feltus , Pamela. "Great Warrior Leaders/Thinkers: LeMay, Curtis E." Air...77 Feltus , "Great Warrior Leaders/Thinkers: LeMay, Curtis E." Air University Library. 78 Anders, Fighting Airmen, 247. 79 Ibid. 80 LeMay, Mission...With LeMay, 231. 81 Feltus , "Great Warrior Leaders/Thinkers: LeMay, Curtis E." Air University Library. 82 Anders, Fighting Airmen, 253. 83 Johnson

Sterblichkeit: der paradoxe Kunstgriff des Lebens - Eine Betrachtung vor dem Hintergrund der modernen Biologie

NASA Astrophysics Data System (ADS)

Verbeek, Bernhard

Leben gibt es auf der Erde seit fast 4 Mio. Jahren, trotz allen Katastrophen. Die Idee des Lebens scheint unsterblich. Der Tod aber offenbar auch. Jedes Lebewesen ist davon bedroht, ja für Menschen und andere "höhere“ Lebewesen ist er im Lebensprogramm eingebaut - todsicher. Diese Tatsache ist alles andere als selbstverständlich. Ist sie überhaupt kompatibel mit dem Prinzip der Evolution, nach dem der am besten Angepasste überlebt?

Benchmarking Peer Production Mechanisms, Processes & Practices

ERIC Educational Resources Information Center

Fischer, Thomas; Kretschmer, Thomas

2008-01-01

This deliverable identifies key approaches for quality management in peer production by benchmarking peer production practices and processes in other areas. (Contains 29 footnotes, 13 figures and 2 tables.)[This report has been authored with contributions of: Kaisa Honkonen-Ratinen, Matti Auvinen, David Riley, Jose Pinzon, Thomas Fischer, Thomas…

Anders Breivik: Extreme Beliefs Mistaken for Psychosis.

PubMed

Rahman, Tahir; Resnick, Phillip J; Harry, Bruce

2016-03-01

The case of Anders Breivik, who committed mass murder in Norway in 2011, stirred controversy among forensic mental health experts. His bizarrely composed compendium and references to himself as the "Knights Templar" raised concerns that he had a psychotic mental illness. Beliefs such as Mr. Breivik's that precede odd, unusual, or extremely violent behavior present a unique challenge to the forensic evaluator, who sometimes struggles to understand those beliefs. Psychotic disorder frequently is invoked to characterize odd, unusual, or extreme beliefs, with a classification that has evolved over time. However, the important concept of overvalued idea, largely ignored in American psychiatry, may better characterize these beliefs in some cases. We discuss the definitions of delusion and overvalued ideas in the context of Anders Breivik's rigidly held extreme beliefs. We also review the British definition of overvalued idea and discuss McHugh's construct, to introduce the term "extreme overvalued belief" as an aid in sharpening the forensic evaluator's conceptualization of these and similar beliefs. © 2016 American Academy of Psychiatry and the Law.

Provincial Reconstruction Teams: Who’s in Charge?

DTIC Science & Technology

2011-05-20

permission of General Mattis. 41 U.S. President, NSPD-44. 42 Stephen R. Covey, The 7 Habits of Highly Effective People , (New York: Simon & Schuster...September 5, 2010). Covey, Stephen R. The 7 Habits of Highly Effective People . New York: Simon & Schuster, Inc., 1990. Crane, Conrad C. and W

Speech Research.

DTIC Science & Technology

1979-12-31

629. Mattis, S., French, J. H., & Rapin, I. Dyslexia in children and young adults: Three independent neuropsychological syndromes. Developmental...Knights & D. K. Bakker (Eds.), Neuropsychology ofA learning disorders: Theoretical approaches. Baltimore: University Park Press, 1976. Shankweiler...sounds connected with comfort, discomfort, and hunger . When babbling appears, it is mixed in with cooing but distinguished by its syllable-like

Office of the Under Secretary of Defense for Personnel and Readiness

Science.gov Websites

Mattis, Danish Defense Minister Reaffirm Defense Relationship Fri, 25 May 2018 19:25:00 GMT Trump Thanks Deputy Secretary of Defense for Total Force Management as it relates to readiness; National Guard and Reserve component affairs; health affairs; training; and personnel requirements and management, including

Learning Science through Talking Science in Elementary Classroom

ERIC Educational Resources Information Center

Tank, Kristina Maruyama; Coffino, Kara

2014-01-01

Elementary students in grade two make sense of science ideas and knowledge through their contextual experiences. Mattis Lundin and Britt Jakobson find in their research that early grade students have sophisticated understandings of human anatomy and physiology. In order to understand what students' know about human body and various systems,…

Effect of interstitial impurities on the field dependent microwave surface resistance of niobium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinello, M., E-mail: mmartine@fnal.gov; Checchin, M.; Department of Physics, Illinois Institute of Technology, Chicago, Illinois 60616

Previous work has demonstrated that the radio frequency surface resistance of niobium resonators is dramatically reduced when nitrogen impurities are dissolved as interstitial in the material. This effect is attributed to the lowering of the Mattis-Bardeen surface resistance with increasing accelerating field; however, the microscopic origin of this phenomenon is poorly understood. Meanwhile, an enhancement of the sensitivity to trapped magnetic field is typically observed for such cavities. In this paper, we conduct a systematic study on these different components contributing to the total surface resistance as a function of different levels of dissolved nitrogen, in comparison with standard surfacemore » treatments for niobium resonators. Adding these results together, we are able to show which is the optimum surface treatment that maximizes the Q-factor of superconducting niobium resonators as a function of expected trapped magnetic field in the cavity walls. These results also provide insights on the physics behind the change in the field dependence of the Mattis-Bardeen surface resistance, and of the trapped magnetic vortex induced losses in superconducting niobium resonators.« less

Effect of interstitial impurities on the field dependent microwave surface resistance of niobium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinello, M.; Grassellino, A.; Checchin, M.

Previous work has demonstrated that the radio frequency surface resistance of niobium resonators is dramatically reduced when nitrogen impurities are dissolved as interstitial in the material. The origin of this effect is attributed to the lowering of the Mattis and Bardeen surface resistance contribution with increasing accelerating field. Meanwhile, an enhancement of the sensitivity to trapped magnetic field is typically observed for such cavities. In this paper we conduct the first systematic study on these different components contributing to the total surface resistance as a function of different levels of dissolved nitrogen, in comparison with standard surface treatments for niobiummore » resonators. Adding these results together we are able to show for the first time which is the optimum surface treatment that maximizes the Q-factor of superconducting niobium resonators as a function of expected trapped magnetic field in the cavity walls. Lastly, these results also provide new insights on the physics behind the change in the field dependence of the Mattis and Bardeen surface resistance, and of the trapped magnetic vortex induced losses in superconducting niobium resonators.« less

Effect of interstitial impurities on the field dependent microwave surface resistance of niobium

DOE PAGES

Martinello, M.; Grassellino, A.; Checchin, M.; ...

2016-08-09

Previous work has demonstrated that the radio frequency surface resistance of niobium resonators is dramatically reduced when nitrogen impurities are dissolved as interstitial in the material. The origin of this effect is attributed to the lowering of the Mattis and Bardeen surface resistance contribution with increasing accelerating field. Meanwhile, an enhancement of the sensitivity to trapped magnetic field is typically observed for such cavities. In this paper we conduct the first systematic study on these different components contributing to the total surface resistance as a function of different levels of dissolved nitrogen, in comparison with standard surface treatments for niobiummore » resonators. Adding these results together we are able to show for the first time which is the optimum surface treatment that maximizes the Q-factor of superconducting niobium resonators as a function of expected trapped magnetic field in the cavity walls. Lastly, these results also provide new insights on the physics behind the change in the field dependence of the Mattis and Bardeen surface resistance, and of the trapped magnetic vortex induced losses in superconducting niobium resonators.« less

Outside the Golden Gate: Prospects and Comparisons in Finnish Adult Higher Education.

ERIC Educational Resources Information Center

Parjanen, Matti, Ed.; And Others

This book contains four articles on adult higher education (AHE) in Finland. In the preface, Matti Parjanen outlines the development of AHE in Finland and discusses the rationale for the book. In "Adult Education and Universities in the Era of Economic Depression," Osmo Kivinen and Risto Rinne examine the dilemma between the mission of…

The Mattis Way of War: An Examination of Operational Art in Task Force 58 and 1st Marine Division

DTIC Science & Technology

2014-12-12

Research Questions Did his innovations work? Are they worthy of repeating? Did his style evolve as he increased in responsibility? What role did current...staff was born both out of necessity, lack of physical space, and personal style . Efficiencies gained from a small staff generate speed in orders...

Official Website of the Joint Chiefs of Staff

Science.gov Websites

Corps photo by Lance Cpl. Haley McMenamin May 22, 2018 - Fitness means more than just passing a test Australia's Chief of Defence Did You Know We're on Instagram? Check out our latest post! Check out our latest Instagram post! #GenDunford and #SecDef Mattis brief reporters on the U.S., French and UK coordinated

Quantifying Enhanced Microbial Dehalogenation Impacting the Fate and Transport of Organohalide Mixtures in Contaminated Sediments

DTIC Science & Technology

2012-02-01

supplying Anacostia River sediment, Dr. Matti Verta, Finnish Environment Institute, for providing Kymijoki River sediment, and the Meadowlands...dehalogenating activity; 2) Characterize the effect of sedimentary conditions on the ( bio )transformation rates of organohalide mixtures and their...the fate and transport of organohalide contaminants, co-amendments and ( bio )transformation products under various bioremediation scenarios. The

Mattis dementia rating scale (DRS) normative data for the brazilian middle-age and elderly populations.

PubMed

Foss, Maria Paula; de Carvalho, Viviane Amaral; Machado, Thais Helena; Dos Reis, Geraldo Cássio; Tumas, Vitor; Caramelli, Paulo; Nitrini, Ricardo; Porto, Cláudia Sellitto

2013-01-01

To expand norms for the Mattis Dementia Rating Scale (DRS) for the Brazilian middle-age and elderly populations. The DRS was administered to 502 individuals without cognitive deficits, 312 women and 190 men, aged 50 years or over and with educational level ranging from 0 to 13 years or more. The sample was composed of subjects who participated in other studies, from Caeté (Minas Gerais state), Ribeirão Preto (São Paulo state) and São Paulo (São Paulo state). Participants were divided into four schooling groups (illiterate, 1 to 4 years, 5 to 12 years and 13 years or more). The subjects were divided into four groups according to age (50 to 60, 61 to 70, 71 to 80, and 80 years or over). Normative data for DRS scores are expressed as percentile values. The group with lowest schooling and subjects older than 80 years had the worst scores. As expected, age and education were strongly correlated with DRS scores. Illiterates and older old individuals performed worse than the other groups. These data might help to improve the accuracy of the diagnosis of cognitive impairment and dementia in Brazilian middle-age and elderly populations.

Setting the Scene--Introduction to Quality in Peer Production of eLearning

ERIC Educational Resources Information Center

Auvinen, Ari-Matti

2008-01-01

The "Setting the scene" deliverable of the QMPP project (www.qmpp.net) has been authored by Mr. Ari-Matti Auvinen (HCI Productions Oy) and many QMPP project partners. In addition to the definition of the scope of the project, it includes also a good list of references to the literature of user-generated content as well as good web links…

The US Army and Security Force Assistance: Assessing the Need for an Institutionalized Advisory Capability

DTIC Science & Technology

2009-03-03

Army Special Forces. Following a 2008 meeting with Gen James N. Mattis (Commander, US Joint Forces Command), Gen James T. Conway (Commandant, US...CAPABILITY Approved by: , Thesis Committee Chair James B. Martin, Ph.D. , Member Gary J. Bjorge, Ph.D. , Member Robert D...Technology: Information technology, bio -technology, weaponry, increased access to information Demographic Changes: Population growth, youth bulge

The National Guard: Recommendations to Develop the Joint Future Force

DTIC Science & Technology

2010-03-01

0209airpowerinafghan.pdf. 23 Statement of General James N. Mattis , USMC, Commander, United States Joint Forces Command, House Armed Services... James R. Locher III, Victory on the Potomac: the Goldwater-Nichols Act Unifies the Pentagon, (College Station: Texas A & M University Press, 2002), 19...pick snubs National Guard, Thursday January 14, 2010, Congress.org, http://www.congress.org/congressorg/ bio /userletter/?letter_id=4520675821

Evolution of the Air Component Commander Post Goldwater-Nichols

DTIC Science & Technology

2013-06-01

example, before Brigadier General James Mattis led Marine forces in the taking of Kandahar, he spoke with Moseley; and they agreed to conduct the...These separated commands and the division of airpower, along 3 James A. Winnefeld and Dana J...Biography: Lieutenant General Michael C. Short,” July 2000., http://www.af.mil/information/ bios /bio.asp?bioID=7136 (accessed March 20, 2013). 27 Short

Hawaii-Hyperspectral Airborne Remote Environmental Sensing (HIHARES󈧍) Experiment

DTIC Science & Technology

2012-03-15

Polynesia and southeastern Asia. Cordia sebestena Kou haole Found worldwide, mostly in warmer regions. Cordyline fruticosa Ti plant It is native to...to obtain spectra of vegetation indigenous to Oahu and from several specialty gardens, spectra of plants common to Australia. Hawaii Coastal...indigenous to Oahu and from several specialty gardens, spectra of plants common to Australia. On November 19, 2008, Dr. Chip Bachmann, Mssrs Mattis and

KITAE II: Knowledge Development in Battlespace Helmand

DTIC Science & Technology

2011-06-01

Sergeant Andrew James Jones 18-09-2010 Private Simon Mundt Jørgensen 22-09-2010 Corporal Matthew Thomas 25-09-2010 Rifleman Suraj Gurung 02-10-2010...targeting driven. See Mattis (2008); For philosophical foundation see Smith (2005, 2006); Nicholson (2006);Mitchell (2004); and a doctrinal...BATTLESPACE IS THE KNOWLEDGE BASE HUMINT 1 SIGINT1 OSINT BIO IMINT 1 SIGINT 2 PATROLS HUMINT 2 REACHBACK IMINT 2 Sources OTHER… Actionable Assets Organic

Beyond-the-Box Thinking on Future War: The Art and Science of Unrestricted Warfare

DTIC Science & Technology

2009-04-01

Studies Institute, US Army War College, 2008. Mattis , James N., and Frank Hoffman. “Future Warfare: The Rise of Hybrid Warfare.” Proceedings...nanotechnologies will augment the current bio -chemical capabilities, moving the battlefield into a microscopic arena. As seen before, the traditional American way...Military Trans-military Non-military Atomic Warfare Diplomatic Warfare Financial Warfare Conventional Warfare Network Warfare Trade Warfare Bio

MicroRNAs in Prostate Cancer

DTIC Science & Technology

2008-11-01

microarray, gene expression, androgen 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18 . NUMBER OF PAGES 19a. NAME OF RESPONSIBLE...Anindya Dutta; Yong Sun Lee; Hak Kyun Kim MicroRNAs are short single-stranded RNAs of 18 -22 bases length that are produced by the processing of...we hope to go to xenograft assays to demonstrate that microRNA alterations can suppress metastasis. REFERENCES: 1. Mattie, M.D., et al

Mathematical Model of HIF-1 alpha Pathway, Oxygen Transport and Hypoxia

DTIC Science & Technology

2017-09-01

interpret experimental data in terms of underlying mechanisms. Such experiments, if quantitative , can also be used to calibrate and further parameterize...Wing Air Force Research Laboratory Wright-Patterson AFB OH 45433-5707 STINFO COPY Work Unit Manager MATTIE.DAV ID.R.123010 1880 Digitally signed by...MONITORING AGENCY NAME(S) AND ADDRESS(ES) Air Force Materiel Command* Air Force Research Laboratory 711th Human Performance Wing Human Effectiveness

Center for Development of Security Excellence (CDSE) 2013 Year End Report

DTIC Science & Technology

2013-01-01

Humphrey Deputy Director, CDSE CDSE STATEMENT Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc bibendum dapibus dui, at porta nunc. In eget...accumsan odio. Donec rutrum varius purus, vitae venenatis urna porttitor eget. Mauris lorem dolor , facilisis eget purus quis, adipiscing tincidunt...ac quam at gravida. Cras a ligula suscipit, lobortis dolor vel, feugiat diam. Proin mattis lectus sit amet pellentesque interdum. Cras porttitor

Mattis dementia rating scale (DRS) normative data for the brazilian middle-age and elderly populations

PubMed Central

Foss, Maria Paula; de Carvalho, Viviane Amaral; Machado, Thais Helena; dos Reis, Geraldo Cássio; Tumas, Vitor; Caramelli, Paulo; Nitrini, Ricardo; Porto, Cláudia Sellitto

2013-01-01

OBJECTIVE To expand norms for the Mattis Dementia Rating Scale (DRS) for the Brazilian middle-age and elderly populations. METHODS The DRS was administered to 502 individuals without cognitive deficits, 312 women and 190 men, aged 50 years or over and with educational level ranging from 0 to 13 years or more. The sample was composed of subjects who participated in other studies, from Caeté (Minas Gerais state), Ribeirão Preto (São Paulo state) and São Paulo (São Paulo state). Participants were divided into four schooling groups (illiterate, 1 to 4 years, 5 to 12 years and 13 years or more). The subjects were divided into four groups according to age (50 to 60, 61 to 70, 71 to 80, and 80 years or over). RESULTS Normative data for DRS scores are expressed as percentile values. The group with lowest schooling and subjects older than 80 years had the worst scores. CONCLUSION As expected, age and education were strongly correlated with DRS scores. Illiterates and older old individuals performed worse than the other groups. These data might help to improve the accuracy of the diagnosis of cognitive impairment and dementia in Brazilian middle-age and elderly populations. PMID:29213861

Skin sagging treatment - underarms

MedlinePlus

... Kline D, Hendrix CR, Foster C, Anders M. ACE-sponsored research: best triceps exercises. August 2011. www.acefitness.org/certifiednewsarticle/1562/ace-sponsored-research-best-triceps-exercises . Accessed December 16, ...

Building Security in the Persian Gulf

DTIC Science & Technology

2010-01-01

developments within ACT, and building on the leadership and success of the outgoing U.S. commander, General James Mattis , U.S. Marine Corps (who retains...following the end of the war in Iraq. The author would like to thank RAND President James Thomson, who supported the development of a proj- ect plan designed...bers from diverse issue backgrounds, all of whom have extensive experience both in research and in policy formulation. These were David Aaron, James

Systems Theory, Unity of Effort, and Military Leadership

DTIC Science & Technology

2012-12-14

adventure, and without you, all else is meaningless. To my Daddy, LTC (R) James R. Livingood. I am who I am, because of you. You taught me to question...decisions as applied within his localized operational environment (Headquarters, Department of the Army 2012b). 6General Mattis and others argue that...systems network theory have made incredible steps forward in the past few years, through the work of social scientists Nicholas Christakis and James

High Frontier - The Journal for Space, Cyberspace & Missile Professionals. Volume 6, Number 1, November 2009

DTIC Science & Technology

2009-11-01

signs of just that!” In a response sent several days following Van Riper’s e-mail, [US Marine Corp Lt Gen James ] Mattis —who is now in the post Van...29 Regaining Credibility: Making Nuclear Sustainment a Model of Excellence Col James D. Fisher...Taverney, retired and Col James D. Rendleman, retired . . . . . . 53 Legislative Perspective Weapon Systems Acquisition Reform Act Maj Jung H. Ha

JPRS Report West Europe

DTIC Science & Technology

1988-08-12

that first graders are the nicest, like all in one big family. Well-behaved and obedient. Maybe Matti teases Maija a little bit and Pekka pushes Kalle ...France as early as 1971 . The system designed for Finland is an all-weather ver- sion and it was originally intended to specifically destroy low-flying...ISTAT study covers principally the three years of 1984-86, but also examines the evolution of crime in Italy since 1971 . And this could not have

Hydroprocessed Esters and Fatty Acids (HEFA) Bio-Based Jet Fuels: Sensory Irritation Study and Human Health Hazard Assessment

DTIC Science & Technology

2013-06-30

AFRL-RH-FS-TR-2014-0001 Hydroprocessed Esters and Fatty Acids (HEFA) Bio -Based Jet Fuels: Sensory Irritation Study and Human Health Hazard...Karen L. Mumy Brian A. Wong R. Arden James James Reboulet Brian Sharits Michael Grimm Nathan Gargas Naval Medical Research Unit - Dayton...Wright-Patterson AFB OH Richard C. Striebich AFRL/RQTF Wright-Patterson AFB OH David R. Mattie Bioeffects Division Molecular Bioeffects Branch

Evaluation of the Occupational Risks from Jet Fuel (Toxicity Screening Battery)

DTIC Science & Technology

2012-09-01

1α may serve as a marker of epidermal damage or stress due to irritation in this in vitro model. As an alternative to the 3-dimensional human skin...AFRL-RH-FS-SR-2013-0003 Final Report: Evaluation of the Occupational Risks from Jet Fuel (Toxicity Screening Battery) David R. Mattie...2. REPORT TYPE Special Report 3. DATES COVERED (From - To) Oct 2010 – Dec 2011 4. TITLE AND SUBTITLE Evaluation of the Occupational Risks from

Anomaly manifestation of Lieb-Schultz-Mattis theorem and topological phases

NASA Astrophysics Data System (ADS)

Cho, Gil Young; Hsieh, Chang-Tse; Ryu, Shinsei

2017-11-01

The Lieb-Schultz-Mattis (LSM) theorem dictates that emergent low-energy states from a lattice model cannot be a trivial symmetric insulator if the filling per unit cell is not integral and if the lattice translation symmetry and particle number conservation are strictly imposed. In this paper, we compare the one-dimensional gapless states enforced by the LSM theorem and the boundaries of one-higher dimensional strong symmetry-protected topological (SPT) phases from the perspective of quantum anomalies. We first note that they can both be described by the same low-energy effective field theory with the same effective symmetry realizations on low-energy modes, wherein non-on-site lattice translation symmetry is encoded as if it were an internal symmetry. In spite of the identical form of the low-energy effective field theories, we show that the quantum anomalies of the theories play different roles in the two systems. In particular, we find that the chiral anomaly is equivalent to the LSM theorem, whereas there is another anomaly that is not related to the LSM theorem but is intrinsic to the SPT states. As an application, we extend the conventional LSM theorem to multiple-charge multiple-species problems and construct several exotic symmetric insulators. We also find that the (3+1)d chiral anomaly provides only the perturbative stability of the gaplessness local in the parameter space.

Anders Jonas Ångström and the foundation of spectroscopy - Commemorative article on the second centenary of his birth

NASA Astrophysics Data System (ADS)

Reif-Acherman, Simón

2014-12-01

The Swedish astronomer Anders Jonas Ångström, born two centuries ago and professor of physics at Uppsala University, was one of the founders of optical spectroscopy. By using diffraction gratings out of glass plates with fine scorings across the face, he was able to observe the spectrum of the Sun, announcing in 1862 that he had discovered the lines of hydrogen in the solar spectrum. His most important work, ;Recherches sur la Spectre Solaire;, including an atlas of close to a thousand spectral lines, became the standard of spectroscopy for at least a quarter of a century. This article deals with his life as well as his main contributions to the development of several areas of physical science, stressing his pioneer activities in spectroscopy.

Drahtlose Audioübertragung

NASA Astrophysics Data System (ADS)

Niehoff, Wolfgang

Für die drahtlose Übertragung von Audiosignalen werden elektromagnetische Wellen als Trägersignale genutzt. Auch der Rundfunk bedient sich dieser Wellen auf unterschiedlichen Frequenzen, ebenso Kommunikationsdienste wie der Mobilfunk, WLAN, Bluetooth und andere Funkdienste (Abb. 19.1).

Lieb-Schultz-Mattis-type filling constraints in the 1651 magnetic space groups

NASA Astrophysics Data System (ADS)

Watanabe, Haruki

2018-04-01

We present a systematic study of the filling constraints to realize a "trivial" insulator symmetric under magnetic space group M . The filling ν must be an integer multiple of mM to avoid spontaneous symmetry breaking or fractionalization in gapped phases. We improve the value of mM in the literature and prove the tightness of the constraint for the majority of magnetic space groups. The result may shed light on the material search of exotic magnets with fractionalization.

Theory of disordered unconventional superconductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keles, A.; Andreev, A. V.; Spivak, B. Z., E-mail: spivak@uw.edu

In contrast to conventional s-wave superconductivity, unconventional (e.g., p- or d-wave) superconductivity is strongly suppressed even by relatively weak disorder. Upon approaching the superconductormetal transition, the order parameter amplitude becomes increasingly inhomogeneous, leading to effective granularity and a phase ordering transition described by the Mattis model of spin glasses. One consequence of this is that at sufficiently low temperatures, between the clean unconventional superconducting and the diffusive metallic phases, there is necessarily an intermediate superconducting phase that exhibits s-wave symmetry on macroscopic scales.

Capability Surprise (Report of the Defense Science Board 2008 Summer Study). Volume 1: Main Report

DTIC Science & Technology

2009-09-01

fact, this has already happened, at least to a degree. Gen. James Mattis sent a memo in March 2009 to Defense Secretary Robert Gates calling for the... bio , but with a focus on threats to military operations, we chose not to. “Surprising” surprises—those many that the nation might have known about...Victor 3/Akula Quieting Undetected use of foreign technology Prepared because we had anticipated capability in general Soviet Bio -weapons Program

MicroRNA-200c: A Novel Way to Attack Breast Cancer Metastases by Restoring the Epithelial Phenotype

DTIC Science & Technology

2012-12-01

65:7065- 7070. 3. Mattie , M.D., Benz, C.C., Bowers, J., Sensinger, K., Wong, L., Scott, G.K., Fedele, V., Ginzinger, D., Getts, R., and Haqq, C...50 μg by Bradford protein assay ( Bio - Rad, Hercules, CA, USA), separated by SDS-PAGE gels and transferred onto polyvinylidene difluoride (PVDF...Richer), and the National Institutes of Health R01CA74285 (D. Yee).We thank Aik-Choon Tan (University of Colorado, Division of Medical Oncology) for bio

Agent-Based Modeling and Simulation: Proposal for Department of Defense Support to the Whole of Government Approach In Afghanistan

DTIC Science & Technology

2012-05-11

September 1, 2011). 5 Abraham Maslow , Motivation and Personality, Third Edition, Harper and Row Publishers, 1954, 91-236. 6 Joshua M. Epstein, “Why...Response Program." Joint Force Quarterly, no. 37 (2005): 46, http://www.dtic.mil/doctrine/jel/jfq_pubs/0937.pdf (accessed October 15, 2011). Maslow ... Abraham . Motivation and Personality. Third ed. New York, New York: Harper and Row, 1954. Mattis, James. US Central Command Commander’s Posture

Airmindedness Without Airheadedness: A Way Ahead for Airmen to Lead Design

DTIC Science & Technology

2013-02-14

officers from any Service. 18 Notes 1. Edward C. Cardon and Lieutenant Colonel Steve Leonard, “Unleashing Design: Planning and the Art of...SAASS], 2006), 82.) 12. General James N. Mattis, Memorandum for U.S. Joint Forces Command, 9 October 2009. 13. Cardon and Leonard, “Unleashing...Design,” 3. See also Grant Martin, “A Tale of Two Design Efforts (and why they both Failed in Afghanistan),” Small Wars Journal (July 7, 2011): 1-15

The case of Anders Behring Breivik - language of a lone terrorist.

PubMed

Leonard, Cecilia H; Annas, George D; Knoll, James L; Tørrissen, Terje

2014-01-01

Anders Behring Breivik carried out a massacre in Norway on July 22, 2011, killing a total 77 persons and leaving 42 others severely wounded. He detonated a bomb in Oslo and then drove to the island of Utøya, where he shot and killed youngsters gathered at a youth camp. The authors performed an analysis of Breivik's writing style in his extensive manifesto which he published hours before the attacks, and also referred to the two psychiatrists' reports. The first report concluded that he suffered from paranoid schizophrenia. The authors concurred with the second report. Breivik seemed to be a person with narcissistic personality disorder, whose grandiosity might have caused him to be regarded initially as mentally deranged; however, closer examination revealed his deliberate attempt to methodically indoctrinate and deceive potential readers, to alarm potential targets and to terrorize a nation. Copyright © 2014 John Wiley & Sons, Ltd.

Sizing up the competition: quantifying the influence of the mental lexicon on auditory and visual spoken word recognition.

PubMed

Strand, Julia F; Sommers, Mitchell S

2011-09-01

Much research has explored how spoken word recognition is influenced by the architecture and dynamics of the mental lexicon (e.g., Luce and Pisoni, 1998; McClelland and Elman, 1986). A more recent question is whether the processes underlying word recognition are unique to the auditory domain, or whether visually perceived (lipread) speech may also be sensitive to the structure of the mental lexicon (Auer, 2002; Mattys, Bernstein, and Auer, 2002). The current research was designed to test the hypothesis that both aurally and visually perceived spoken words are isolated in the mental lexicon as a function of their modality-specific perceptual similarity to other words. Lexical competition (the extent to which perceptually similar words influence recognition of a stimulus word) was quantified using metrics that are well-established in the literature, as well as a statistical method for calculating perceptual confusability based on the phi-square statistic. Both auditory and visual spoken word recognition were influenced by modality-specific lexical competition as well as stimulus word frequency. These findings extend the scope of activation-competition models of spoken word recognition and reinforce the hypothesis (Auer, 2002; Mattys et al., 2002) that perceptual and cognitive properties underlying spoken word recognition are not specific to the auditory domain. In addition, the results support the use of the phi-square statistic as a better predictor of lexical competition than metrics currently used in models of spoken word recognition. © 2011 Acoustical Society of America

75 FR 14258 - Unblocking of Specially Designated Nationals Pursuant to Executive Order 13224

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-24

..., Pakistan; c/o Alam General Store Shop 17, Awami Market, Peshawar, Pakistan; c/o Zahir Shah s/o Murad Khan Ander Sher, Peshawar, Pakistan (individual) [SDGT] The removal of the individual's name from the list of...

Modeling the Effect of Temperature on Ozone-Related Mortality.

EPA Science Inventory

Modeling the Effect of Temperature on Ozone-Related Mortality. Wilson, Ander, Reich, Brian J, Neas, Lucas M., Rappold, Ana G. Background: Previous studies show ozone and temperature are associated with increased mortality; however, the joint effect is not well explored. Underst...

Interview with Alexander Cohen.

PubMed

Cohen, Alexander Ander

2017-05-01

Ander Cohen speaks to Adam Price-Evans, Commissioning Editor of Future Cardiology: Alexander (Ander) Cohen MBBS (Hons), MSc, MD, FRACP is a vascular physician and epidemiologist at Guy's and St Thomas' Hospital, King's College (London, UK). He graduated with honors in medicine and honors in surgery from the University of Melbourne, Australia, and became a fellow of the Royal Australasian College of Physicians in 1990. He was awarded an MSc in Epidemiology from the London School of Hygiene and Tropical Medicine, University of London in 1991 with a thesis on the metabolic syndrome in South-Asian populations. In 1998, he was awarded an MD with a thesis on the epidemiology of venous thromboembolism and thromboprophylaxis. In addition to his clinical work, he is involved in designing, managing and analyzing clinical trials from Phase I to IV. He is the Chairman and a member of many international steering committees for multicenter trials, epidemiological and pharmacoeconomic studies, and was previously the Director of Clinical Research and an Epidemiologist in Thrombosis Research at King's College Hospital.

Sensitivity and specificity of Addenbrooke's Cognitive Examination, Mattis Dementia Rating Scale, Frontal Assessment Battery and Mini Mental State Examination for diagnosing dementia in Parkinson's disease.

PubMed

Kaszás, B; Kovács, N; Balás, I; Kállai, J; Aschermann, Z; Kerekes, Z; Komoly, S; Nagy, F; Janszky, J; Lucza, T; Karádi, K

2012-06-01

Among the non-motor features of Parkinson's disease (PD), cognitive impairment is one of the most troublesome problems. Highly sensitive and specific screening instruments for detecting dementia in PD (PDD) are required in the clinical practice. In our study we evaluated the sensitivity and specificity of different neuropsychological tests (Addenbrooke's Cognitive Examination, ACE; Frontal Assessment Battery, FAB and Mattis Dementia Rating Scale, MDRS) in 73 Parkinson's disease patients without depression. By receiver operating characteristic curve analysis, these screening instruments were tested against the recently established clinical diagnostic criteria of PDD. Best cut-off score for ACE to identify PDD was 80 points (sensitivity = 74.0%, specificity = 78.1%). For FAB the most optimal cut-off value was 12 points (sensitivity = 66.3%, specificity = 72.2%); whereas for MDRS it was 125 points (sensitivity = 89.8%, specificity = 98.3%). Among the examined test batteries, MDRS had the best clinicometric profile for detecting PDD. Although the types of applied screening instruments might differ from movement disorder clinic to clinic within a country, determination of the most specific and sensitive test for the given population remains to be an important task. Our results demonstrated that the specificity and sensitivity of MDRS was better than those of ACE, FAB and MMSE in Hungary. However, further studies with larger sample size and more uniform criteria for participation are required to determine the most suitable screening instrument for cognitive impairment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Insect Flight: Computation and Biomimetic Design

DTIC Science & Technology

2008-05-31

Mechanics, 37, 183-210 (2005). • Z. Jane Wang, ”Insect Flight”, McGraw Hill Year Book of Science and Technology, 2006. • Anders Andersen, Umberto Pesavento ...Umberto Pesavento , and Z. Jane Wang, ’Analysis of transitions between fluttering, tumbling and steady descent of falling cards’, Journal of Fluid

Role of Merlin in the Growth and Transformation of Arachnoidal Cells

DTIC Science & Technology

2009-01-01

studies on the chemotherapeutic agent, hydroxyurea , were performed using meningioma cells grown in the galea (25), and tests on celecoxib were performed...Anders M, Kiesewetter F, Marschalek R, Koch UH, Fahlbusch R (1997) Hydroxyurea for treatment of unresectable and recurrent meningiomas. I. Inhibition of

Brennstoffzellentechnik

NASA Astrophysics Data System (ADS)

Kurzweil, Peter

Brennstoffzellen "verbrennen" einen Brennstoff nicht mit einer Feuererscheinung unter Freisetzung von Wärme. Anders als ihr Name vermuten lässt, wird üblicherweise Wasserstoff wie in einer Batterie durch elektrochemische Vorgänge verstromt statt verbrannt. Brennstoffzellen wandeln die im Brennstoff gespeicherte chemische Energie direkt in Elektrizität — ohne Umweg über Wärme!

Apollo 8 prime crew stand beside gondola for centrifuge training

NASA Technical Reports Server (NTRS)

1968-01-01

The Apollo 8 prime crew stands beside the gondola in bldg 29 after suiting up for centrifuge training in the Manned Spacecraft Center's (MSC) Flight Acceleration Facility. Left to right, are Astronauts William A. Anders, lunar module pilot; James A. Lovell Jr.,command module pilot; and Frank Borman, commander.

Two members of Apollo 8 crew suited up for centrifuge training

NASA Technical Reports Server (NTRS)

1968-01-01

Two members of the Apollo 8 prime crew stand beside the gondola in bldg 29 after suiting up for centrifuge training in the Manned Spacecraft Center's (MSC) Flight Acceleration Facility. They are Astronauts William A. Anders (left), lunar module pilot; and James A. Lovell Jr., command module pilot.

Subtraction Radiography for the Diagnosis of Bone Lesions in Dogs.

DTIC Science & Technology

1984-05-31

Avail ander Journal of Periodontology Dist Special Ř 211 East Chicago Avenue Room 924 Chicago, IL 60611 Dear Sirs: I m submitting an original...research article titled "Subtraction Radiography for the Diagnosis of Bone Lesions in Dogs" solely to the Journal of Periodontology for review and

Faust and the Padshah Sphinx: Reshaping the NATO Alliance to Win in Afghanistan

DTIC Science & Technology

2010-02-24

Afghanistan is one of the most complex environments to combat. Its history, independent tribes, diverse ethnicities (Hazaaras, Pashtuns, Uzbeks and...reporting this statistic to the CJ2. 20 This occurred at the SHAPE Afghanistan Intelligence Conference, Krakow, Poland , May 2008. 21 Anders Fogh

Arabism and Islam: Stateless Nations and Nationless States

DTIC Science & Technology

1990-07-01

Notes 1. NationalGeographic, vol. 119, no. 1 (January 1961), p. 84. 2. Michel Foucault , quoted in translation from Keith Michael Baker, "Memory...Islamic Jihad released a photograph of the corpse o f French hostage Michel Seurat, a respected scholar of the Arab-Muslim world. Terry Ander

European Glaucoma Society Terminology and Guidelines for Glaucoma, 4th Edition - Part 1Supported by the EGS Foundation

PubMed Central

2017-01-01

Foreword It gives me pleasure to introduce the 4th edition of the EGS Guidelines. The Third edition proved to be extremely successful, being translated into 7 languages with over 70000 copies being distributed across Europe; it has been downloadable, free, as a pdf file for the past 4 years. As one of the main objectives of the European Glaucoma Society has been to both educate and standardize glaucoma practice within the EU, these guidelines were structured so as to play their part. Glaucoma is a living specialty, with new ideas on causation, mechanisms and treatments constantly appearing. As a number of years have passed since the publication of the last edition, changes in some if not all of these ideas would be expected. For this new edition of the guidelines a number of editorial teams were created, each with responsibility for an area within the specialty; updating where necessary, introducing new diagrams and Flowcharts and ensuring that references were up to date. Each team had writers previously involved with the last edition as well as newer and younger members being co-opted. As soon as specific sections were completed they had further editorial comment to ensure cross referencing and style continuity with other sections. Overall guidance was the responsibility of Anders Heijl and Carlo Traverso. Tribute must be made to the Task Force whose efforts made the timely publication of the new edition possible. Roger Hitchings Chairman of the EGS Foundation www.eugs.org The Guidelines Writers and Contributors  Augusto Azuara Blanco Luca Bagnasco Alessandro Bagnis Keith Barton Christoph Baudouin Boel Bengtsson Alain Bron Francesca Cordeiro Barbara Cvenkel Philippe Denis Christoph Faschinger Panayiota Founti Stefano Gandolfi David Garway Heath Francisco Goni Franz Grehn Anders Heijl Roger Hitchings Gabor Hollo Tony Hommer Michele Iester Jost Jonas Yves Lachkar Giorgio Marchini Frances Meier Gibbons Stefano Miglior Marta Misiuk-Hojo Maria Musolino Jean Philippe Nordmann Norbert Pfeiffer Luis Abegao Pinto Luca Rossetti John Salmon Leo Schmetterer Riccardo Scotto Tarek Shaarawy Ingeborg Stalmans Gordana Sunaric Megevand Ernst Tamm John Thygesen Fotis Topouzis Carlo Enrico Traverso Anja Tuulonen Ananth Viswanathan Thierry Zeyen The Guidelines Task Force  Luca Bagnasco Anders Heijl Carlo Enrico Traverso Augusto Azuara Blanco Alessandro Bagnis David Garway Heath Michele Iester Yves Lachkar Ingeborg Stalmans Gordana Sunaric Mégevand Fotis Topouzis Anja Tuulonen Ananth Viswanathan The EGS Executive Committee  Carlo Enrico Traverso (President) Anja Tuulonen (Vice President) Roger Hitchings (Past President) Anton Hommer (Treasurer) Barbara Cvenkel Julian Garcia Feijoo David Garway Heath Norbert Pfeiffer Ingeborg Stalmans The Board of the European Glaucoma Society Foundation  Roger Hitchings (Chair) Carlo E. Traverso (Vice Chair) Franz Grehn Anders Heijl John Thygesen Fotis Topouzis Thierry Zeyen The EGS Committees  CME and Certification  Gordana Sunaric Mégevand (Chair) Carlo Enrico Traverso (Co-chair) Delivery of Care  Anton Hommer (Chair) EU Action  Thierry Zeyen (Chair) Carlo E. Traverso (Co-chair) Education  John Thygesen (Chair) Fotis Topouzis (Co-chair) Glaucogene  Ananth Viswanathan (Chair) Fotis Topouzis (Co-chair) Industry Liaison  Roger Hitchings (Chair) Information Technology  Ingeborg Stalmans (Chair) Carlo E. Traverso (Co-chair) National Society Liaison  Anders Heijl (Chair) Program Planning  Fotis Topouzis (Chair) Ingeborg Stalmans (Co-chair) Quality and Outcomes  Anja Tuulonen (Chair) Augusto Azuara Blanco (Co-chair) Scientific  Franz Grehn (Chair) David Garway Heath (Co-chair) PMID:27378485

The Therapeutic "Mis"conception: An Examination of its Normative Assumptions and a Call for its Revision.

PubMed

Mathews, Debra J H; Fins, Joseph J; Racine, Eric

2018-01-01

Dissecting Bioethics, edited by Tuija Takala and Matti Hayry, welcomes contributions on the conceptual and theoretical dimensions of bioethics. The department is dedicated to the idea that words defined by bioethicists and others should not be allowed to imprison people's actual concerns, emotions, and thoughts. Papers that expose the many meanings of a concept, describe the different readings of a moral doctrine, or provide an alternative angle to seemingly self-evident issues are particularly appreciated. To submit a paper or to discuss a suitable topic, contact Tuija Takala at tuija.takala@helsinki.fi.

Visuoperception test predicts pathologic diagnosis of Alzheimer disease in corticobasal syndrome

PubMed Central

Tierney, Michael; Wassermann, Eric M.; Spina, Salvatore; Oblak, Adrian L.; Ghetti, Bernardino; Grafman, Jordan; Huey, Edward

2014-01-01

Objective: To use the Visual Object and Space Perception Battery (VOSP) to distinguish Alzheimer disease (AD) from non-AD pathology in corticobasal syndrome (CBS). Methods: This clinicopathologic study assessed 36 patients with CBS on the VOSP. All were autopsied. The primary dependent variable was a binary pathologic outcome: patients with CBS who had primary pathologic diagnosis of AD (CBS-AD, n = 10) vs patients with CBS without primary pathologic diagnosis of AD (CBS-nonAD, n = 26). We also determined sensitivity and specificity of individual VOSP subtests. Results: Patients with CBS-AD had younger onset (54.5 vs 63.6 years, p = 0.001) and lower memory scores on the Mattis Dementia Rating Scale–2 (16 vs 22 points, p = 0.003). Failure on the VOSP subtests Incomplete Letters (odds ratio [OR] 11.5, p = 0.006), Position Discrimination (OR 10.86, p = 0.008), Number Location (OR 12.27, p = 0.026), and Cube Analysis (OR 45.71 p = 0.0001) had significantly greater odds of CBS-AD than CBS-nonAD. These associations remained when adjusting for total Mattis Dementia Rating score, disease laterality, education, age, and sex. Receiver operating characteristic curves demonstrated significant accuracy for Incomplete Letters and all VOSP spatial subtests, with Cube Analysis performing best (area under the curve 0.91, p = 0.0004). Conclusions: In patients with CBS, failure on specific VOSP subtests is associated with greater odds of having underlying AD. There may be preferential involvement of the dorsal stream in CBS-AD. Classification of evidence: This study provides Class II evidence that some subtests of the VOSP accurately distinguish patients with CBS-AD from those without AD pathology (e.g., Cube Analysis sensitivity 100%, specificity 77%). PMID:24991033

Spanish version of the Mattis Dementia Rating Scale-2 for early detection of Alzheimer's disease and mild cognitive impairment.

PubMed

Boycheva, Elina; Contador, Israel; Fernández-Calvo, Bernardino; Ramos-Campos, Francisco; Puertas-Martín, Verónica; Villarejo-Galende, Alberto; Bermejo-Pareja, Félix

2018-06-01

We aimed to analyse the clinical utility of the Mattis Dementia Rating Scale (MDRS-2) for early detection of Alzheimer's disease (AD) and amnestic mild cognitive impairment (MCI) in a sample of Spanish older adults. A total of 125 participants (age = 75.12 ± 6.83, years of education =7.08 ± 3.57) were classified in three diagnostic groups: 45 patients with mild AD, 37 with amnestic MCI-single and multiple domain and 43 cognitively healthy controls (HCs). Reliability, criterion validity and diagnostic accuracy of the MDRS-2 (total and subscales) were analysed. The MDRS-2 scores, adjusted by socio-demographic characteristics, were calculated through hierarchical multiple regression analysis. The global scale had adequate reliability (α = 0.736) and good criterion validity (r = 0.760, p < .001) with the Mini-Mental State Examination. The optimal cut-off point between AD patients and HCs was 124 (sensitivity [Se] = 97% and specificity [Sp] = 95%), whereas 131 (Se = 89%, Sp = 81%) was the optimal cut-off point between MCI and HCs. An optimal cut-off point of 123 had good Se (0.97), but poor Sp (0.56) to differentiate AD and MCI groups. The Memory and Initiation/Perseveration subscales had the highest discriminative capacity between the groups. The MDRS-2 is a reliable and valid instrument for the assessment of cognitive impairment in Spanish older adults. In particular, optimal capacity emerged for the detection of early AD and MCI. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Preservice Literacy Instruction and the Benefits of Direct Instruction

ERIC Educational Resources Information Center

Sturtz, Tanya I.

2009-01-01

Teacher preparation programs have improved over the years (Wold, Grisham, Farnan, & Lenski, 2008), but one area that some teacher preparation programs are still working on is how much knowledge about reading does a teacher need to know to teach literacy effectively (Anders, Hoffman, & Duffy, 2000). The concern is strengthened with the research on…

Optimizing Performance of Scientific Visualization Software to Support Frontier-Class Computations

DTIC Science & Technology

2015-08-01

Hypersonic Sciences Branch) for providing sample datasets and permission to use an image of Q_Criterion isosurface for this report; Dr Anders Grimsrud...10.1. EnSight CSM and CFD Post processing; c2014 [accessed 2015 July 6] http:// www.ceisoftware.com. Main Page. XDMF; 2014 Nov 7 [2015 July 6] http

What PISA Measures: Some Remarks on Standardized Assessment and Science Education

ERIC Educational Resources Information Center

Roehl, Tobias

2015-01-01

Drawing on a sociocultural perspective on educational assessment the empirical examples of Margareta Serder and Anders Jakobsson serve as a starting point for a critical analysis of PISA and the image of science education it perpetuates. While PISA claims to neutrally measure competencies relevant to science education, I argue that the test…

75 FR 14192 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Joint Venture...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-24

... Production Act of 1993--Joint Venture Under Tip Award No. 70NANB10H014 To Perform Project Entitled: Automated... Project Entitled: Automated Nondestructive Evaluation and Rehabilitation System (``ANDERS'') for Bridge... approaches or fragmented NDE, (2) comprehensive condition and structural assessment (including the...

Debt, the Migrant, and the Refugee: "Lampedusa" on Stage

ERIC Educational Resources Information Center

Hemelryk Donald, Stephanie

2018-01-01

This article discusses Anders Lustgarten's play, "Lampedusa." The play is ostensibly about refugees and the Mediterranean crossing, as well as addressing EU migration, debt, and austerity. The article develops the idea of the debtor in neo-liberal economics suggesting that the refugee is required to become a debtor on settlement. While…

Temperature Scales: Celsius, Fahrenheit, Kelvin, Reamur, and Romer.

ERIC Educational Resources Information Center

Romer, Robert H.

1982-01-01

Traces the history and development of temperature scales which began with the 17th-century invention of the liquid-in-glass thermometer. Focuses on the work of Olaf Romer, Daniel Fahrenheit, Rene-Antoine de Reamur, Anders Celsius, and William Thomson (Lord Kelvin). Includes experimental work and consideration of high/low fixed points on the…

The Expansion of the Education Sector in Sweden During the 20th Century.

ERIC Educational Resources Information Center

Ohlsson, Rolf

1985-01-01

Three investigations on quantitative changes in higher education in Sweden are described. In Anders Nilsson's dissertation, "Study Financing and Social Recruitment to Higher Education (1920-1976)," attention was focused on changes in college recruitment from 1920 until reforms in 1977; the effect of various college financing conditions…

Wie verstehen Schülerinnen und Schüler den Begriff der Unendlichkeit?

NASA Astrophysics Data System (ADS)

Schimmöller, Tabea

Wie Hilbert bereits feststellte, wirkt die Idee der Unendlichkeit, wie keine andere, schon seit Zeiten sehr anregend und fruchtbar auf den Verstand und bewegt das Gemüt der Menschen. Der Begriff der Unendlichkeit bedarf aber auch, wie kein anderer, der Aufklärung, denn mit ihm eröffnet sich ein weites Feld, welches nicht nur aus vielen verschiedenen Definitionen besteht, sondern auch aus völlig unterschiedlichen Disziplinen. Physiker suchen immer dringender nach einer "Theorie für Alles" oder einer "Weltformel", Kosmologen beschäftigen sich unter anderem mit der Ewigkeit des Universums, Theologen interessiert eher die Unendlichkeit Gottes, Philosophen diskutieren unter anderem Grenzfragen zwischen Naturwissenschaft und Philosophie und die Mathematiker versuchen den Paradoxien des Unendlichen einen Sinn zu geben. Und so wird ersichtlich, dass nichts abstrakter ist als das Unendliche: Obwohl die Unendlichkeit für die unterschiedlichsten Wissenschaften von großer Bedeutung ist, "[ist] in der Wirklichkeit das Unendliche nirgends zu finden, [egal] was für Erfahrungen und Beobachtungen und welcherlei Wissenschaft wir auch heranziehen".

Anders Celsius' Contributions to Meridian Arc Measurements and the Establishment of an Astronomical Observatory in Uppsala

NASA Astrophysics Data System (ADS)

Stempels, H. C.

Astronomy has been on the curriculum of Uppsala University from at least the middle of the 15th century. However, since Uppsala also was the ecclesiastical centre of Sweden, the acceptance of new ideas, such as the Copernican heliocentric system, was slow. At the same time, more peripheral universities in the Swedish empire, including Dorpat/Tartu, enjoyed a larger freedom. It was not until the early 18th century that a `modern' astronomy emerged in Uppsala. This effort was to a large extent led by Anders Celsius (1701--1744), who was able to establish good international contacts with astronomers in continental Europe. Celsius participated in De Maupertuis' expedition to the far north of Sweden, in order to measure the meridian arc and determine the shape of the Earth. This paper explores how Celsius became involved in De Maupertuis' expedition, and how this effort paved the way to the establishment of a fully equipped astronomical observatory, including an extensive collection of books and instruments, most of which survives up to this day.

Schönheit und andere Provokationen - Eine neue evolutionsbiologische Theorie der Kunst

NASA Astrophysics Data System (ADS)

Junker, Thomas

Die Evolution hat viele spektakuläre Phänomene hervorgebracht - von der Eleganz des Vogelflugs über die gigantischen Körper der Dinosaurier und die farbenprächtige Vielfalt der Korallenriffe bis hin zu ihrem jüngsten Geniestreich - der menschlichen Kunst. Die schönen Künste - Malerei, Bildhauerei und Architektur, Theater, Tanz, Oper und Filmkunst, Musik und Literatur - Produkte der Evolution? Diese Vorstellung mutet vielen Menschen fremd an, aber wie könnte es anders sein? Denn wenn Charles Darwin recht hat, dann sind nicht nur die körperlichen Merkmale der Menschen als Antworten auf die Erfordernisse des Lebens entstanden, sondern auch ihre geistigen Fähigkeiten und Verhaltensweisen. Im Jahr 1859 hatte er auf den letzten Seiten seines berühmten Buches über die Entstehung der Arten eine kühne Prophezeiung gemacht: Durch die Evolutionstheorie werde es "zu einer bemerkenswerten Revolution in der Naturwissenschaft kommen […]. Die Psychologie wird auf die neue Grundlage gestellt, dass jede geistige Kraft und Fähigkeit notwendigerweise durch graduelle Übergänge erworben wird“ (Darwin 1859, S. 484, 488; Junker 2008).

Elemente moderner, schlanker Produktionssysteme

NASA Astrophysics Data System (ADS)

Bartholomay, Christian; Boppert, Julia; Dickmann, Eva; Dickmann, Philipp; Gröbner, Michael; Harting, Lothar; Leikep, Sabine; Michels, Friedhelm; Pfister, Johannes; Reitz, Andreas; Schedlbauer, Michael; Takeda, Hitoshi; Thews, Michael; Wilbert, Fred

Meilensteine der modernen Produktion mit Lean Production, Total Quality Management, Six Sigma, Supply Chain Management, Lean Management und Lean Enterprise können zu effizienteren Abläufen führen. In der betrieblichen Praxis existiert jedoch eine Vielzahl von Zielkonflikten basierend auf Richtlinien von Material Requirements Planning- (MRP), Controlling- und anderen Systemen. Nur wenige Spezialisten in größeren Unternehmen sind im Stande, die Komplexität über die Grenzen eines Fachgebiets hinaus im Detail zu verstehen. Fachübergreifendes Verständnis scheitert an der Komplexität der Gesamtproblematik. Entscheidungen verschiedenster Fachbereiche begrenzen die maximal erreichbare Effizienz des Materialflusses. Logistik und Materialfluss werden daher in vielen Unternehmen als unabdingbare Kernkompetenz verstanden. Um eine schlanke Produktion, einen optimalen Materialfluss und somit minimale Produktkosten zu erreichen, sind folglich vielfältige andere Fachthemen als Vorraussetzungen zu beherrschen. Erst dann ist es in der Produktionslogistik möglich, im Vergleich zu einem Top-Benchmark erfolgreich zu sein. Um im täglichen Konkurrenzkampf die Nase auch morgen noch vorne zu haben" ist es nötig, über den Preis hinaus auch noch völlig andere Problemstellungen zu beherrschen.

On the Relations between Parents' Ideals and Children's Autonomy

ERIC Educational Resources Information Center

de Ruyter, Doret J.; Schinkel, Anders

2013-01-01

In this article Doret J. de Ruyter and Anders Schinkel argue that parents' ideals can enhance children's autonomy, but that they may also have a detrimental effect on the development of children's autonomy. After describing the concept of "ideals" and elucidating a systems theoretical conception of autonomy, de Ruyter and…

Strahlen-und kinetische Waffen: Neue Waffentechniken und Rüstungskontrolle

NASA Astrophysics Data System (ADS)

Neuneck, Götz

Laserstrahlen, Mikrowellen oder elektromagnetische Beschleuniger lassen sich nicht nur für zivile, sondern für militärische Zwecke einsetzen. Die Aufgabe einer vorbeugenden Rüstungskontrolle wäre es, diese wie andere künftige Waffentechnologien auf ihren destabilisierenden Charakter hin zu untersuchen und ihre Stationierung zu beschränken oder zu verhindern.

n/a

NASA Image and Video Library

1971-07-26

During the Apollo 15 pre-launch activity in the launch control center's firing room 1 at Kennedy Space Center, the then recently appointed NASA Administrator, Dr. James C. Fletcher (right) speaks with (Left to right) William Anders, executive secretary of the National Aeronautics and Space Council; Lt. General Sam Phillips, former Apollo Program Director; and Dr. Wernher von Braun, NASA's Deputy Associate Administrator for planning.

Apollo 8 prime crew inside centrifuge gondola in bldg 29 during training

NASA Technical Reports Server (NTRS)

1968-01-01

The Apollo 8 prime crew inside the centrifuge gondola in bldg 29 during centrifuge training in the Manned Spacecraft Center's (MSC) Flight Acceleration Facility (view with crew lying on back). Left to right, are Astronauts Frank Borman, commander; James A. Lovell Jr., command module pilot; and William A. Anders, lunar module pilot.

Defense.gov Special Report: NATO 25th Summit Meeting

Science.gov Websites

Representatives from 60 countries and organizations are participating in the 25th NATO summit in Chicago - the said at the conclusion of the alliance's summit in Chicago. Story NATO Secretary General Terms Summit a Chicago have accomplished what they set out to do, NATO Secretary General Anders Fogh Rasmussen said

Experimental Design and Analysis for the FIST (Fire Support Team) Force Development Testing and Experimentation II.

DTIC Science & Technology

1985-10-01

median service time for a FIST IHQ to service Copperhead missions while in review mode and for mission workload (FO + ARMOR + CPH) was only 6.0...07703 Uazhin.tou, DC 20036 2 Coui-,ander 1 Comwanaer US Aruy larry Diaiaond Labs. US Army Belvoir ATTN: AIILHD- TD , Dr. Scully Research & Development

Caring, Sharing in the Big Sky--Writer, Photographer Explore Five of Montana's Tribal Colleges

ERIC Educational Resources Information Center

Worley, Jerry

2010-01-01

The author travels across Montana with a former student and photographer, Anders Andersson, and says that visiting tribal colleges is the best way to really understand them. In this article, he writes about five tribal colleges in Montana: (1) Little Big Horn College (LBHC); (2) Chief Dull Knife College (CDKC); (3) Stone Child College (SCC); (4)…

12th Annual Science and Engineering Technology Conference/DoD TECH Exposition

DTIC Science & Technology

2011-06-23

compound when planning horizons grow: long design - test - build-field-adapt lead-times exacerbate uncertain futures problems, overload designs , and...ERS Environment ERS: Tools and Technologies to Facilitate Adaptability & Trustability 4. Tying design , physical and computational testing 6...science, engineering concepts, processes, and design tools to: • Continuously coordinate design , testing , and production with warfighter review to

The TRACE Model of Speech Perception.

DTIC Science & Technology

1984-11-01

One approach is to try to find relatively invariant -- generally relational -- features (e.g., Stevens and Blumstein, 1981). Another approach has...t Dr. Anders Ericsson I Dr. Steven W. Keele Department oi Psychology Dept. of Psychology University of Colorado University of Oregon Boulder, CO...Parallel distributed processing: Explorations in the microstructue of cogni- tion. Vol. 1: Foundations. Cambridge, MA: Bradford Books. Stevens , K

78 FR 61981 - Culturally Significant Objects Imported for Exhibition Determinations: “Anders Zorn: Sweden's...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-08

... October 1, 1999, Delegation of Authority No. 236-3 of August 28, 2000 (and, as appropriate, Delegation of... State (telephone: 202- 632-6467). The mailing address is U.S. Department of State, SA-5, L/PD, Fifth Floor (Suite 5H03), Washington, DC 20522-0505. Dated: October 1, 2013. Evan M. Ryan, Assistant Secretary...

Command History. 1968. Volume 1. Sanitized.

DTIC Science & Technology

1968-01-01

752 Mobility ...... ..... ..... ................................ ..... 756 Artiilery/ Mortar /Rocket/Countermeasures...I- mortar attacks. I urge that we continue to impress upon corn .,anders at all level. the need to remain offensive- minded and to move troops out...in NVN and another month after joining the NVA 95th Regiment in the Konturn- Cambodia border area in July. After firing mortars at A. hamlet near Doc

The delivery of organic matter from asteroids and comets to the early surface of Mars

NASA Technical Reports Server (NTRS)

Flynn, G. J.

1996-01-01

Carbon delivered to the Earth by interplanetary dust particles may have been an important source of pre-biotic organic matter (Anders, 1989). Interplanetary dust is shown to deliver an order-of-magnitude higher surface concentration of carbon onto Mars than onto Earth, suggesting interplanetary dust may be an important source of carbon on Mars as well.

Chemical composition and cytotoxic activity of Garcinia atroviridis Griff. ex T. Anders. essential oils in combination with tamoxifen.

PubMed

Tan, Wen-Nee; Lim, Jia-Qin; Afiqah, Fatin; Nik Mohamed Kamal, Nik Nur Syazni; Abdul Aziz, Fatin Athirah; Tong, Woei-Yenn; Leong, Chean-Ring; Lim, Jun-Wei

2018-04-01

Garcinia atroviridis Griff. ex T. Anders. is used as a medication agent in folkloric medicine. The present study was to examine the chemical composition of the stem bark and leaf of G. atroviridis as well as their cytotoxic effects against MCF-7 cells. The constituents obtained by hydrodistillation were identified using GC-MS. The stem bark oil (EO-SB) composed mainly the palmitoleic acid (51.9%) and palmitic acid (21.9%), while the leaf oil (EO-L) was dominated by (E)-β-farnesene (58.5%) and β-caryophyllene (16.9%). Treatment of MCF-7 cells using EO-L (100 μg/mL) caused more than 50% cell death while EO-SB did not induce cytotoxic effect. EO-L has stimulated the growth of BEAS-2B normal cells, but not in MCF-7 cancerous cells. The IC 50 of EO-L in MCF-7 and BEAS-2B cells were 71 and 95 μg/mL, respectively. A combination treatment of EO-L and tamoxifen induced more cell death than the treatment with drug alone at lower doses.

Update on Service Management Project

ScienceCinema

None

2018-05-11

GS and IT Service Management project status meeting - Distribution: Sigurd Lettow, Frederic Hemmer, Thomas Pettersson, David Foster, Matti Tiirakari, GS&IT; Service Providers When and where: Thursday 2nd September at 10:00-11:30 in IFiltration Plant (222-R-001) Dear All, We would like to inform you about progress made on different topics like the Service Catalogue, the new Service Management Tool and the Service Desk. We would also like to present the plan for when we hope to go live and what this will mean for all of you running and providing services today. We will need your active support and help in the coming months to make this happen. GS&IT; Service Management Teams Reinoud Martens, Mats Moller

Finite quasiparticle lifetime in disordered superconductors.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zemlicka, M.; Neilinger, P.; Trgala, M

We investigate the complex conductivity of a highly disordered MoC superconducting film with k(F)l approximate to 1, where k(F) is the Fermi wave number and l is the mean free path, derived from experimental transmission characteristics of coplanar waveguide resonators in a wide temperature range below the superconducting transition temperature T-c. We find that the original Mattis-Bardeen model with a finite quasiparticle lifetime, tau, offers a perfect description of the experimentally observed complex conductivity. We show that iota is appreciably reduced by scattering effects. Characteristics of the scattering centers are independently found by scanning tunneling spectroscopy and agree with thosemore » determined from the complex conductivity.« less

Effective Client Management: Maximizing The Influence of External Sponsors Over Affiliated Armed Groups

DTIC Science & Technology

2017-12-01

MANAGEMENT : MAXIMIZING THE INFLUENCE OF EXTERNAL SPONSORS OVER AFFILIATED ARMED GROUPS by Anders C. Hamlin December 2017 Thesis Co...burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instruction, searching...existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information . Send comments regarding this

Personnel discussing Gemini 11 space flight in Mission Control

NASA Image and Video Library

1966-09-12

S66-52157 (12 Sept. 1966) --- Discussing the Gemini-11 spaceflight in the Mission Control Center are: (left to right) Christopher C. Kraft Jr., (wearing glasses), Director of Flight Operations; Charles W. Mathews (holding phone), Manager, Gemini Program Office; Dr. Donald K. Slayton (center, checked coat), Director of Flight Crew Operations; astronaut William A. Anders, and astronaut John W. Young. Photo credit: NASA

Closing the Gap: Measuring the Social Identity of Terrorists

DTIC Science & Technology

2008-09-01

considering social psychological aspects of terrorism studies. Despite what might be apparent within the media and even parts of academic circles, terrorism...MEASURING THE SOCIAL IDENTITY OF TERRORISTS by Keith W. Ludwick September 2008 Thesis Advisor: Anders Strindberg Second Reader: David...COVERED Master’s Thesis 4. TITLE AND SUBTITLE Closing the Gap: Measuring the Social Identity of Terrorists 6. AUTHOR(S) Keith W. Ludwick 5

Educating "The New Norwegian We": An Examination of National and Cosmopolitan Education Policy Discourses in the Context of Extremism and Islamophobia

ERIC Educational Resources Information Center

Osler, Audrey; Lybaek, Lena

2014-01-01

Across Europe there are growing concerns about Islamophobia and far-right and anti-democratic movements. Until Anders Behring Breivik's July 2011 attacks in which 77 died, Norway's vulnerability was not perceived as great as that of other jurisdictions. Breivik declared his abhorrence of multiculturalism but also drew the world's attention to…

NATO’s Eastern Agenda in a New Strategic Era

DTIC Science & Technology

2003-01-01

gratitude to Anders Åslund, Ronald Asmus, Carl Bildt, Zbigniew Brzezinski , Per Carlsen, Keith Crane, Stephan DeSpiegeleire, James Dobbins, Ingemar...in which Walesa reportedly met privately with a group of senior Polish officers and encouraged them to speak out against Defense Minister Piotr ...transforms the geopolitics of Europe, especially Central Europe. As Zbigniew Brzezinski has pointed out, without Ukraine Russia ceases to be a

Geologic map and digital database of the Cougar Buttes 7.5' quadrangle, San Bernardino County, California

USGS Publications Warehouse

Powell, R.E.; Matti, J.C.; Cossette, P.M.

2000-01-01

The Southern California Areal Mapping Project (SCAMP) of Geologic Division has undertaken regional geologic mapping investigations in the Lucerne Valley area co-sponsored by the Mojave Water Agency and the San Bernardino National Forest. These investigations span the Lucerne Valley basin from the San Bernardino Mountains front northward to the basin axis on the Mojave Desert floor, and from the Rabbit Lake basin east to the Old Woman Springs area. Quadrangles mapped include the Cougar Buttes 7.5' quadrangle, the Lucerne Valley 7.5' quadrangle (Matti and others, in preparation b), the Fawnskin 7.5' quadrangle (Miller and others, 1998), and the Big Bear City 7.5' quadrangle (Matti and others, in preparation a). The Cougar Buttes quadrangle has been mapped previously at scales of 1:62,500 (Dibblee, 1964) and 1:24,000 (Shreve, 1958, 1968; Sadler, 1982a). In line with the goals of the National Cooperative Geologic Mapping Program (NCGMP), our mapping of the Cougar Buttes quadrangle has been directed toward generating a multipurpose digital geologic map database. Guided by the mapping of previous investigators, we have focused on improving our understanding and representation of late Pliocene and Quaternary deposits. In cooperation with the Water Resources Division of the U.S. Geological Survey, we have used our mapping in the Cougar Buttes and Lucerne Valley quadrangles together with well log data to construct cross-sections of the Lucerne Valley basin (R.E. Powell, unpublished data, 1996-1998) and to develop a hydrogeologic framework for the basin. Currently, our mapping in these two quadrangles also is being used as a base for studying soils on various Quaternary landscape surfaces on the San Bernardino piedmont (Eppes and others, 1998). In the Cougar Buttes quadrangle, we have endeavored to represent the surficial geology in a way that provides a base suitable for ecosystem assessment, an effort that has entailed differentiating surficial veneers on piedmont and pediment surfaces and distinguishing the various substrates found beneath these veneers.

[Production of accentuated personality traits in baroque opera : Opera buffa Arcifanfano-Re dei matti (1749)].

PubMed

Brunner, J; Hirsch, T; Steger, F

2016-05-01

Madness served primarily as a form of amusement for the spectators in operas of the seventeenth century. This representation was far removed from clinical reality. This circumstance changed in the eighteenth century at the time when tragic madness emerged in numerous operas. The opera buffa Arcifanfano-Re dei matti (Arcifanfano-King of fools, premiered in 1749 in Venice, text by Carlo Goldoni 1707-1793 and music by Baldassare Galuppi 1706-1785), which continuously enacts a realm of fools and is meant to appear amusing, is riddled with psychopathological abnormalities for which a retrospective diagnosis is methodologically rejected. However, the opera presents many subjects for working out a typology of fools based on outlasting personality traits of the protagonists. The libretto is investigated. A musical analysis is spared. The conceptualized typology of fools in the opera, which is oriented towards the seven main vices or deadly sins serves, in the tradition of moral satire, to critically hold up a mirror to the audience to reflect their own vices by an amusing characterization of the latter. Historically classified, the treatment of fools by means of isolation, custody, locking up in cages as well as authoritarian measures of submission reflects the custom in those days before humanizing the treatment of people with mental illness in the course of the Enlightenment and the French Revolution. The opera Arcifanfano is essentially characterized by continuous madness. A typology of the fools can be worked out from the precise depiction of the personalities. A mirror is held up to the spectators in terms of vices, in the tradition of the contemporary baroque opera. At the same time, the opera can be classified psychiatrically and historically as a seismograph of its time when in the seventeenth and eighteenth centuries people with mental illness were isolated and incarcerated.

The Way We Think: A Research Symposium on Conceptual Integration and the Nature and Origin of Cognitively Modern Human Beings (Odense, Denmark, August 19-23, 2002). Volumes I [and] II.

ERIC Educational Resources Information Center

Hougaard, Anders, Ed.; Lund, Steffen Nordahl, Ed.

2002-01-01

These 2 volumes include papers and abstracts of papers presented at the August 2002 "The Way We Think" conference in Denmark. Papers and abstracts of papers in the two volumes include: "Blending and Conceptual Disintegration" (Anders Hougaard); "Levels of Blending, Disintegration, and Language Evolution" (Carl Bache); "Conceptual Integration,…

Final Report: High Power Semiconductor Laser Sources,

DTIC Science & Technology

1989-01-01

Mittelstein, Yasuhiko Arakawa, ) Anders Larssonb) and Amnon Yariv California Institute of Technology, Pasadena, California 91 125~412 (Received 7 July...Electronics and Commu- nication Engineers of Japan. He is a member of the Institute of Electronics Yasuhiko Arakawa S󈨑-M󈨔) was born in Ai- and...Gain, Modulation Response, and Spectral Linewidth in AlGaAs Quantum Well Lasers YASUHIKO ARAKAWA. MEMBER, IEEE. AND AMNON YARIV. FELLOW. IEEE Abstract

Membrane Insertion Profiles of Peptides Probed by Molecular Dynamics Simulations

DTIC Science & Technology

2008-07-17

Membrane insertion profiles of peptides probed by molecular dynamics simulations In-Chul Yeh,* Mark A. Olson,# Michael S. Lee,*#§ and Anders...a methodology based on molecular dynamics simulation techniques to probe the insertion profiles of small peptides across the membrane interface. The...profiles of peptides probed by molecular dynamics simulations 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d

The King of Norway: negative individuation, the hero myth and psychopathic narcissism in extreme violence and the life of Anders Behring Breivik.

PubMed

Virtanen, Harri

2013-11-01

The paper discusses negative individuation and the hero myth as developmental concepts. It is suggested that in negative individuation healthy psychological development is hindered and goes astray. Aggression then becomes the central psychic system. Repressed anger is the core element in psychopathic narcissism (Diamond) and malignant narcissism (Kernberg). Both Diamond and Kernberg extend narcissistic personality structure to antisocial, psychopathic personality in an effort to better understand extreme violence. According to Freud, love (libido) and hate (the death drive) are the major motivational systems in the human psyche. In contrast to Freud, Jung sees libido as a life force in general, not simply as a sexual drive. Jung writes about evil and the shadow but does not present a comprehensive theory of the negative development of an individual's life. The concept of negative individuation connects the shadow and the death drive with psychopathology, psychiatry and psychotherapy. In this paper, I explore these concepts in the light of contemporary affect theory according to Kernberg. I also ask how ideology is tied to extreme violence and how it is possible that narcissistic personality structures can lead to such radically different outcomes as were manifested in the lives of Anders Behring Breivik and Steve Jobs. © 2013, The Society of Analytical Psychology.

Deconstructing persecution and betrayal in the discourse of Anders Behring Breivik: A preliminary essay.

PubMed

Cotti, Patricia

2015-08-01

On 22 July 2011, a 32-year-old Norwegian launched two planned murderous rampages claiming the lives of 77 victims. Shortly before his attacks, Anders Behring Breivik uploaded to the internet a self-styled compendium written in English in which he explained the motivation for his attacks. By deconstructing this text and the documentation contained in the first [court-ordered] psychiatric evaluation of Breivik, we can undertake to analyse his sense of persecution. In pursing this analysis, we start with Breivik's description of his personal concept of contemporary European history and politics, and then proceed to the autobiographical and phantasmic aspects of his discourse. The analysis reveals the transformation of love into hate, the original persecutor, the installation of a projection mechanism, notions of betrayal and their subsequent development into an ideology. With Breivik's conceptions thus revealed, we conclude by comparing different psychoanalytic hypotheses which deepen or challenge the Freudian thesis of a defence against a feeling of homosexual love in persecution, and which to the contrary favour the importance of the relationship with the mother, anal sadism or the 'narcissistic rage' behind the genesis of these ideas. We leave open the question of whether there is a constant relationship between feelings of persecution and the tendency to commit criminal acts. Copyright © 2015 Institute of Psychoanalysis.

Organic matter on the early surface of Mars: An assessment of the contribution by interplanetary dust

NASA Technical Reports Server (NTRS)

Flynn, G. J.

1993-01-01

Calculations by Anders and Chyba et al. have recently revived interest in the suggestion that organic compounds important to the development of life were delivered to the primitive surface of the Earth by comets, asteroids or the interplanetary dust derived from these two sources. Anders has shown that the major post-accretion contribution of extraterrestrial organic matter to the surface of the Earth is from interplanetary dust. Since Mars is a much more favorable site for the gentle deceleration of interplanetary dust particles than is Earth, model calculations show that biologically important organic compounds are likely to have been delivered to the early surface of Mars by the interplanetary dust in an order-of-magnitude higher surface density than onto the early Earth. Using the method described by Flynn and McKay, the size frequency distribution, and the atmospheric entry velocity distribution of IDP's at Mars were calculated. The entry velocity distribution, coupled with the atmospheric entry heating model developed by Whipple and extended by Fraundorf was used to calculate the fraction of the particles in each mass decade which survives atmospheric entry without melting (i.e., those not heated above 1600K). The incident mass and surviving mass in each mass decade are shown for both Earth and Mars.

Role of phonons in the metal-insulator phase transition.

NASA Technical Reports Server (NTRS)

Langer, W. D.

1972-01-01

Review, for the transition series oxides, of the Mattis and Lander model, which is one of electrons interacting with lattice vibrations (electron and phonon interaction). The model displays superconducting, insulating, and metallic phases. Its basic properties evolve from a finite crystallographic distortion associated with a dominant phonon mode and the splitting of the Brillouin zone into two subzones, a property of simple cubic and body centered cubic lattices. The order of the metal-insulator phase transition is examined. The basic model has a second-order phase transition and the effects of additional mechanisms on the model are calculated. The way in which these mechanisms affect the magnetically ordered transition series oxides as described by the Hubbard model is discussed.

Learning science through talking science in elementary classroom

NASA Astrophysics Data System (ADS)

Tank, Kristina Maruyama; Coffino, Kara

2014-03-01

Elementary students in grade two make sense of science ideas and knowledge through their contextual experiences. Mattis Lundin and Britt Jakobson find in their research that early grade students have sophisticated understandings of human anatomy and physiology. In order to understand what students' know about human body and various systems, both drawings and spoken responses provide rich evidence of their understanding of the connections between science drawings and verbal explanations. In this forum contribution, we present several theoretical connections between everyday language and science communication and argue that building communication skills in science are essential. We also discuss how young participants should be valued and supported in research. Finally we discuss the need for multimodal research methods when the research participants are young.

A New First-Principles Calculation of Field-Dependent RF Surface Impedance of BCS Superconductor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Binping; Reece, Charles E.

2014-02-01

There is a need to understand the intrinsic limit of radiofrequency (RF) surface impedance that determines the performance of superconducting RF cavities in particle accelerators. Here we present a field-dependent derivation of Mattis-Bardeen theory of the RF surface impedance of BCS superconductors based on the shifted density of states resulting from coherently moving Cooper pairs. Our theoretical prediction of the effective BCS RF surface resistance (Rs) of niobium as a function of peak surface magnetic field amplitude agrees well with recently reported record low loss resonant cavity measurements from JLab and FNAL with carefully, yet differently, prepared niobium material. Themore » surprising reduction in resistance with increasing field is explained to be an intrinsic effect.« less

Genome Sequences of Mycobacteriophages Amgine, Amohnition, Bella96, Cain, DarthP, Hammy, Krueger, LastHope, Peanam, PhelpsODU, Phrank, SirPhilip, Slimphazie, and Unicorn.

PubMed

Anders, Kirk R; Barekzi, Nazir; Best, Aaron A; Frederick, Gregory D; Mavrodi, Dmitri V; Vazquez, Edwin; Amoh, Nana Yaa A; Baliraine, Frederick N; Buchser, William J; Cast, Thomas P; Chamberlain, Carmen E; Chung, Hui-Min; D'Angelo, William A; Farris, Christian T; Fernandez-Martinez, Mariceli; Fischman, Haley D; Forsyth, Mark H; Fortier, Anna G; Gallo, Kara F; Held, Greta J; Lomas, Miguel A; Maldonado-Vazquez, Natalia Y; Moonsammy, Claudia H; Namboote, Peace; Paudel, Sudip; Polley, Sarah-Elizabeth M; Reyes, Gabriella M; Rubin, Michael R; Saha, Margaret S; Stukey, Joseph; Tobias, Tristan D; Garlena, Rebecca A; Stoner, Ty H; Cresawn, Steven G; Jacobs-Sera, Deborah; Pope, Welkin H; Russell, Daniel A; Hatfull, Graham F

2017-12-07

We report the genome sequences of 14 cluster K mycobacteriophages isolated using Mycobacterium smegmatis mc²155 as host. Four are closely related to subcluster K1 phages, and 10 are members of subcluster K6. The phage genomes span considerable sequence diversity, including multiple types of integrases and integration sites. Copyright © 2017 Anders et al.

Launch of Apollo 8 lunar orbit mission

NASA Image and Video Library

1968-12-21

S68-56001 (21 Dec. 1968) --- The Apollo 8 (Spacecraft 103/Saturn 503) space vehicle is launched from Pad A, Launch Complex 39, Kennedy Space Center, at 7:51 a.m. (EST), Dec. 21, 1968. The crew of the Apollo 8 lunar orbit mission is astronauts Frank Borman, commander; James A. Lovell Jr., command module pilot; and William A. Anders, lunar module pilot. Apollo 8 was the first manned Saturn V launch. (Just after ignition)

H.R. 4015, Jobs for Veterans Act. Hearing before the Subcommittee on Benefits of the Committee on Veterans' Affairs, House of Representatives. One Hundred Seventh Congress, Second Session (April 18, 2002).

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Committee on Veterans' Affairs.

This hearing provides the statements from the following individuals: Chairman Simpson; Hon. Silvestre Reyes; Hon. Ander Crenshaw; and Hon. Lane Evans (prepared statement of). This document also includes statements from over 10 wittinesses and contains an article, bill, chart, and statement submitted for the record relating to this hearing.…

China’s Growing Military Power: Perpectives on Security, Ballistic Missiles, and Conventional Capabilities

DTIC Science & Technology

2002-09-01

Rice recently com pared th e present s y stem of agreem ents to th e geocentric concept of th e univ erse; th e future s y s tem of th e w orld to...neces sary . Norm ally , th e reserv e com m and post is staffed by th e w ar zone deputy logistics com m ander, oth er required staff officers

Networking as a Seismograph for Social Development. A Contribution to the Function Expansion of Networks Using the Example of Health Promotion of the Socially Disadvantaged (Netzwerkbildung als Seismograph gesellschaftlicher Entwicklungen: Ein Beitrag zur Funktionserweiterung von Netzwerken am Beispiel der Gesundheitsfoerderung von sozial Benachteiligten)

DTIC Science & Technology

2008-03-01

Miftelzu- wachs profitieren mochten. Je st5rker eine Landesvereinigung Modellprojekte akqui- rieren muss, urn die eigene Funktionsf5higkeit...Denn 5hnlich wie die Krankenkas- sen stehen andere Institutionen und Bereiche wie Sozialversicherungstrager, die Arzteschaft, Institutionen des Sports

Werkbelasting Is Nog Geen Stress (Workload Does Not Necessarily Produce Stress)

DTIC Science & Technology

1991-09-10

Cogmitie en energie 8 1.2 Mentale inspanning 10 2 MENTALE WERKBELASTING 11 2.1 Taakmoeilijkheid 12 2.2 De mens als verwerker van informatie 13 2.3 Het... gevolgen van deze verstoringen: verminderd functioneren en welzijn, slaapstoor- nissen, psychosomatische klachten en verhoogde gezondheidsrisico . 6 Rep.No...zich geen nadelige gevolgen te hebben, mits de situatie maar niet te lang aanhoudt en we ons weer kunnen herstellen; anders gaan negatieve reacties

Towards Optimization of Macrocognitive Processes: Automating Analysis of the Emergence of Leadership in Ad Hoc Teams

DTIC Science & Technology

2014-04-21

Journal of Sociotechnology and Knowledge Development (IJSKD), 4(3), 17-37. Anders S, Schweikhart S, Woods DD, Ebright P, Patterson ES. (2012) The Effects...Ergonomics Society, 282-286. • Patterson ES, Rayo MF, Weiss C, Woods Z, Mount-Campbell AF. Online Training for Resilience Communication Strategies during...Shift Change Handovers, in Proceedings of the Human Factors and Ergonomics Society Annual Meeting. (Sep 2013). 57 (1). 1427- 1431. Woods Z, Beecroft

Launch of Apollo 8 lunar orbit mission

NASA Image and Video Library

1968-12-21

S68-56050 (21 Dec. 1968)--- The Apollo 8 (Spacecraft 103/Saturn 503) space vehicle is launched from Pad A, Launch Complex 39, Kennedy Space Center (KSC), at 7:51 a.m. (EST), Dec. 21, 1968. The crew of the Apollo 8 lunar orbit mission is astronauts Frank Borman, commander; James A. Lovell Jr., command module pilot; and William A. Anders, lunar module pilot. Apollo 8 is the first manned Saturn V launch. (water in foreground, seagulls)

Design of Deflectors for Little Goose Spillway, Snake River, Oregon: A Physical Model Study

DTIC Science & Technology

2017-06-01

model of the spillway. Four different deflector designs were compared relative to flow conditions in the stilling basin and tailrace area of the...performance in a 1:40-scale section model of the spillway. Four different deflector designs were compared relative to flow conditions in the stilling basin and...ER D C/ CH L TR -1 7- 10 Dissolved Gas Abatement Studies Design of Deflectors for Little Goose Spillway, Snake River, Oregon A

Strategic Studies Quarterly. Volume 10, Number 3. Fall 2016

DTIC Science & Technology

2016-09-01

Medicinal Products for Bone Repair: Keep It Simple?,” Advanced Drug Delivery Reviews 84 (April 2015): 30–44. 21. Martin J. Stoddart, Jennifer Bara, and Mauro...A. Müllerm, Martin Majewski, and Christopher H. Evans, “Biologics for Tendon Repair,” Advanced Drug Delivery Reviews 84 (April 2015): 222–39. 27...Laura J. K. Mogler; Andrea K. Carzoli; Alex- ander N. Freiberg; Michael R. Holbrook; Brian K. Martin ; William R. Staplin; Nicholas N. Vahanian

Telomere Length as a Predictor of Aggressive Prostate Cancer

DTIC Science & Technology

2008-11-01

prostate cancer, other prostate diseases, and other cancers. Albadine R, Latour M, Toubaji A, Haffner M, Isaacs WB, Platz EA, Meeker AK, Demarzo AM...PMID: 19267370 Lotan TL, Toubaji A, Albadine R, Latour M, Herawi M, Meeker AK, DeMarzo AM, Platz EA, Epstein JI, Netto GJ. TMPRSS2-ERG gene...Wada S, Yoshimura K, Hipkiss EL, Harris TJ, Yen HR, Goldberg MV, Grosso JF, Getnet D, Demarzo AM, Netto GJ, Anders R, Pardoll DM, Drake CG

Studies in Battle Command

DTIC Science & Technology

1995-01-01

gulars i ttl . te i ewa, le nce r ss i a enstown. enstown, h d nt f t pture orge. tely, l ander t ri , odore ac uncey, ed erate. id...triumph, or another such attack, would finally smash us, and then will come the monster catastrophe--a horrible compound of Afghanistan and Corunna...compromise or compound of all of these.“5 On I6 May, while Pemberton vacillated (much to the disgust of his subordi- nates), Grant simplified the

Who Do We Deploy for Psychological Operations: A Function Profile for TPT Members

DTIC Science & Technology

2008-01-01

doet onderzoek om de ontwikkeling v’an PSYOPS in Nederland te ondersteunen. Een eerste stap, in het goed voorbereiden en uitvoeren van PSYOPS is het...bezit. De focus van het huidige project ligt op de selectiemethode van mensen die PSYOPS functies gaan vervullen. Naast Nederland zijn er ook andere NAVO...deze interviews kwam naar voren dat verschillende landen kampen met dezelfde problemen als Nederland wat betreft de selectie van het PSYOPS personeel

Militaire Toepassingen Van Adaptieve Optiek (Military Applications of Adaptive Optics)

DTIC Science & Technology

2006-09-01

dat op dit moment met de beschikbare theorie mogelijk is. Een ander interessant aspect is de mate waarin de turbulentie effecten het jam patroon...systemen In WEAG studie JP8. 11 is aangetoond dat in theorie adaptieve technieken een verbetering van de prestaties van een DIRCM systeem kunnen...Molenaar; Theorie van de laserscintillometer; TNO repot PHL 1978-16 (1978). TNO-rapport I TNO-DV 2006 A336 35/35 6 Ondertekening Den Haag, september 2006

Verification using Satisfiability Checking, Predicate Abstraction, and Craig Interpolation

DTIC Science & Technology

2008-09-01

297, 2007. 4.10.1 196 [48] Roberto Bruttomesso, Alessandro Cimatti, Anders Franzen, Alberto Grig- gio, Ziyad Hanna, Alexander Nadel, Amit Palti, and...using SAT based conflict analysis. In Formal Methods in Computer Aided Design, pages 33–51, 2002. 1.1, 7 [54] Alessandro Cimatti, Alberto Griggio, and...and D. Vroon. Automatic memory reductions for RTL-level verification. In ICCAD, 2006. 1.2.4, 6.2, 7 [108] Joao P. Marques-Silva and Karem A. Sakallah

Investigating the Role of Akt1 in Prostate Cancer Development Through Phosphorylation-Dependent Regulation of Skp2 Stability and Oncogenic Function

DTIC Science & Technology

2010-09-01

ubiquitin ligase. Science 2001, 294(5540):173-177. 7. Strohmaier H, Spruck CH, Kaiser P, Won KA , Sangfelt O, Reed SI: Human F-box protein hCdc4 targets...Anders H. Berg,1 Alan Tseng,1 Bo Zhai,2 Shavali Shaik,1 Eric Bennett,3 Adriana E. Tron,4 Jessica A. Gasser,1 Alan Lau,1 Steven P. Gygi,2 J. Wade Harper

Apollo 8 crew shown during intravehicular activity during mission

NASA Technical Reports Server (NTRS)

1968-01-01

Astronaut Frank Borman, commander, is shown during intravehicular activity on the Apollo 8 lunar orbit mission. This still print was made from movie film taken by an on-board 16mm motion picture camera (56531); Astronaut William A. Anders, lunar module pilot, is shown during intravehicular activity on the Apollo 8 lunar orbit mission (56532); Astronaut James A. Lovell Jr., command module milot, is shown during intravehicular activity on the Apollo 8 lunar orbit mission (56533).

The moon: Composition determined by nebular processes

USGS Publications Warehouse

Morgan, J.W.; Hertogen, J.; Anders, E.

1978-01-01

The bulk composition of the Moon was determined by the conditions in the solar nebula during its formation, and may be quantitatively estimated from the premise that the terrestrial planets were formed by cosmochemical processes similar to those recorded in the chondrites. The calculations are based on the Ganapathy-Anders 7-component model using trace element indicators, but incorportate improved geophysical data and petrological constraints. A model Moon with 40 ppb U, a core 2% by weight (1.8% metal with ???35% Ni and 0.2% FeS) and Mg/(Fe2++Mg)?????0.75 meets the trace element restrictions, and has acceptable density, heat flow and moment of inertia ratio. The high Ni content of the core permits low-Ti mare basalts to equilibrate with metal, yet still retain substantial Ni. The silicate resembles the Taylor-Jakes?? composition (and in some respects the waif Ganapathy-Anders Model 2a), but has lower SiO2. Minor modifications of the model composition (U=30-35 ppb) yield a 50% melt approximating Apollo 15 green glass and a residuum of olivine plus 3 to 4% spinel; the low SiO2, favors spinel formation, and, contrary to expectation, Cr is not depleted in the liquid. There may no longer be any inconsistency between the cosmochemical approach and arguments based on experimental petrology. ?? 1978 D. Reidel Publishing Company.

Electromagnetic properties of impure superconductors with pair-breaking processes

NASA Astrophysics Data System (ADS)

Herman, František; Hlubina, Richard

2017-07-01

Recently, a generic model was proposed for the single-particle properties of gapless superconductors with simultaneously present pair-conserving and pair-breaking impurity scatterings (the so-called Dynes superconductors). Here we calculate the optical conductivity of the Dynes superconductors. Our approach is applicable for all disorder strengths from the clean limit up to the dirty limit and for all relative ratios of the two types of scattering; nevertheless, the complexity of our description is equivalent to that of the widely used Mattis-Bardeen theory. We identify two optical fingerprints of the Dynes superconductors: (i) the presence of two absorption edges and (ii) finite absorption at vanishing frequencies even at the lowest temperatures. We demonstrate that the recent anomalous optical data on thin MoN films can be reasonably fitted by our theory.

Rethinking Science and Technology Education To Meet the Demands of Future Generations in a Changing World. International Organization for Science and Technology Education (IOSTE) Symposium Proceedings (10th, Foz do Iguacu, Parana, Brazil, July 28-August 2, 2002). Volumes I [and] II.

ERIC Educational Resources Information Center

Bizzo, Nelio, Ed.; Kawasaki, Clarice Sumi, Ed.; Ferracioli, Laercio, Ed.; Leyser da Rosa, Vivian, Ed.

This document is the proceedings of the 10th annual meeting of the International Organization for Science and Technology Education (IOSTE). Papers include: (1) "Liberal Education, Information Assessment and Argumentation in Science-LIA" (Andreas Quale, Anders Isnes, Terje Kristensen, and Ketil Mathiassen); (2) "Placing the History…

Lessons Learned (Vietnam)

DTIC Science & Technology

1966-01-01

and the establishing of joint procedures whereby the above could be accom- plished." USCONARC Comment , Current Tactical Air Command policy ...i.-. . O¼* / t, O231ZGhni stnd~rz...on o ffi.eor -,as assigned. Heo cc= Cncd init~ia2 p...n... to ztais. _an Aviatioc. Ei-;adc standar-dization progr...all concerned. Parag~raphs 2 and 3 contain ma-"erz d-icussed and 6-uidance presented at the Co-ander’s Conierence held this date. 2. POLICY a. F71vin7

Cognitive Bargaining Model: An Analysis Tool for Third Party Incentives?

DTIC Science & Technology

2009-12-01

catalytic by reducing any rally-around-the-flag effect in the target state, bolstering the business class (“commercial bourgeoisie ”), which typically is...9. 136 “Donors Drawing Up Plans for CIS Aid,” Agence France Presse, May 23, 1992. 137 RusData Dialine, “USA—Ukraine: Buy Anytime You Like,” BizEkon...2009). Agence France Presse. “Donors Drawing Up Plans for CIS Aid.” May 23, 1992. Aslund, Anders. How Ukraine Became a Market Economy and

Apollo 8 prime crew seen during water egress training in Gulf of Mexico

NASA Technical Reports Server (NTRS)

1968-01-01

The prime crew of the Apollo 8 mission in life raft awaiting pickup by U.S. Coast Guard helicopter during water egress training in the Gulf of Mexico. They had just egressed Apollo Boilerplate 1102A, at left. Inflated bags were used to upright the boilerplate. Left to right, are Astronauts William A. Anders, lunar module pilot; James A. Lovell Jr., command module pilot; and Frank Borman, commander. A team of Manned Spacecraft Center (MSC) swimmers assisted with the training exercise.

Was leistet ein Sportler? Kraft, Leistung und Energie im Muskel

NASA Astrophysics Data System (ADS)

Thaller, Sigrid; Mathelitsch, Leopold

2006-01-01

Der Leistungsbegriff ist im Sport weiter gefasst als in der Physik. In beiden Fällen liegt der Fokus jedoch auf einer pro Zeiteinheit erfolgten Energieumsetzung. Allerdings gibt die rein physikalische Leistung nicht immer Auskunft über den Energieumsatz der Muskeln. Die Muskelkraft hängt von der Kontraktionsgeschwindigkeit des Muskels ab. Ein Muskel verhält sich also anders als eine Feder. Für den Hochleistungssport müssen die Energieumsätze der Muskeln durch spezielle Trainings- und Nahrungsprogramme optimiert werden.

Environmental Factors Affecting Efficacy of Bifenthrin-Treated Vegetation for Mosquito Control

DTIC Science & Technology

2009-01-01

and Surgeoner 1983, Ander- son et al. 1991, Perich et al. 1993, Cilek and Hallmon 2006), lambda cyhalothrin (Trout et al. 2007, Cilek and Hallmon 2008...insecticide treatment. Leaves were sampled 1–2 days before treatment, on the day of treatment, and at weeks 1, 2, 4, 6, and 7. All plants were watered ...were divided into 2 groups: those with no rainfall and those with heavy rainfall characteris- tic for June–September in north central Florida. Water

Apollo 8 prime crew seen during water egress training in Gulf of Mexico

NASA Image and Video Library

1968-10-19

S68-53217 (19 Oct. 1968) --- Astronaut James A. Lovell Jr., command module pilot of the Apollo 8 prime crew, in special net being hoisted up to a U.S. Coast Guard helicopter during water egress training in the Gulf of Mexico. Awaiting his turn for helicopter pickup is astronaut William A. Anders (in raft), lunar module pilot. Astronaut Frank Borman, commander, had already been picked up. A team of Manned Spacecraft Center (MSC) swimmers assisted with the training exercise.

Apollo 8 prime crew seen during water egress training in Gulf of Mexico

NASA Image and Video Library

1968-10-19

S68-53223 (19 Oct. 1968) --- The prime crew of the Apollo 8 mission in life raft awaiting pickup by U.S. Coast Guard helicopter during water egress training in the Gulf of Mexico. They had just egressed Apollo Boilerplate 1102A, at left. Inflated bags were used to upright the boilerplate. Left to right, are astronauts William A. Anders, lunar module pilot; and Frank Borman, commander. A team of MSC swimmers assisted with the training exercise.

Hierarchical Reinforcement in Continuous State and Multi-Agent Environments

DTIC Science & Technology

2005-09-01

Mahadevan, Chair Andrew G. Barto, Member Victor R . Lesser, Member Weibo Gong, Member W. Bruce Croft, Department Chair Computer Science To my parents...of my cubicle during my unwanted one-year absence. Thank you Colin Barringer , Jad Davis, Andy Fagg, Jeffrey Johns, Anders Jonsson, George Konidaris...transforma- tions of the problem. One definition is that an MDP model M consists of five elements 〈S,A,P , R , I〉 defined as follows:1 • S: is the set of

Prospective Model and Its Methodology of Supplies for the Repair and Maintenance of the Venezuelan Naval Ships to the Third Level.

DTIC Science & Technology

1982-06-01

coastal zone where the entry into Lake Maracaibo is located, as well as Amuay, Punta Cardon, Aruba and Curazao. The mideastern coastal zone is Puerto La ...6 1131. LIST OF REFERENCES 1. Ander-Egg, EzequielI Introduccion a las Tecnicas de Investigacion Social, bditorial liermanitas, Huenos Aires...Francisco, "El control integralo de gestion." Editorial Qunitana Madrid, March 1975. 4. Conceptos Basicos, Ministerio de la Defensa l.A. Diques y

APOLLO VIII - LAUNCH - KSC

NASA Image and Video Library

1968-12-21

S68-56002 (21 Dec. 1968) --- The Apollo 8 (Spacecraft 103/Saturn 503) space vehicle is launched from Pad A, Launch Complex 39, Kennedy Space Center (KSC), at 7:51 a.m. (EST), Dec. 21, 1968. The crew of the Apollo 8 lunar orbit mission is astronauts Frank Borman, commander; James A. Lovell Jr., command module pilot; and William A. Anders, lunar module pilot. Apollo 8 was the first manned Saturn V launch. (F-ls 1/3 way from top of mobile launch tower.)

Apollo 8

NASA Image and Video Library

1968-12-29

S69-16402 (29 Dec. 1968) --- Although it was past 2 a.m., a crew of more than 2,000 people were on hand at Ellington Air Force Base to welcome the members of the Apollo 8 crew back home. Astronauts Frank Borman, James A. Lovell Jr., and William A. Anders had just flown to Houston from the pacific recovery area by way of Hawaii. The three crewmen of the historic Apollo 8 lunar orbit mission are standing at the microphones in center of picture. Photo credit: NASA

Speed Measuring System (Detectoren en Signaalbewerking Voor Het Snelheidsmeetsysteem 4-01)

DTIC Science & Technology

1989-03-01

een hogere nauwkeurigheid te halen dan san de voet van bet signasi mogelijk is bij een grote signaalaniplitude, Wanneer de S/L < 6 is wordt de drempel...snelheidsmeetsysteem 4-01 Niets Uilf deze ultgave mag worden vermenigvuldigd en of openbaar gemaakt door mlddel van druk fotokope microfilm autour~s): of op welke...andere wijze dan 006 zonder voorafgaarode toestemming van TNO J. van der Haven Hetlter I zage geven van net TNO-rappoit aan direct belanghebbenoen is

Testbed Environment for Distributed Observation (testbed omgeving voor gedistribueerde waarneming)

DTIC Science & Technology

2006-05-01

het IP-adres en portnumnmer van de MID halen . Ook de naamn van de XML-file om de NID te beschrijven staat hierin vermeld (in dit geval ’CSD.xmId’) in...DeviceML beschrijving van de NID op te halen . Dit wordt gedaan door een TCP/IP verbinding op te zetten tussen de LUS en de NID (via de DeviceML port...vernisenigvuidigd! enlof openbaar gensaaki door middel van druk, fotokopie, microftinm of op welke andere wijze dan ook, zonder voorafgaande schrifielijke

Plasma studies of a linear magnetron operating in the range from DC to HiPIMS

NASA Astrophysics Data System (ADS)

Anders, André; Yang, Yuchen

2018-01-01

Plasma properties of magnetrons have been extensively studied in the past with the focus on small, research-style magnetrons with planar disk targets. In this contribution, we report on plasma diagnostics of a linear magnetron because the linear geometry is widely used in industry and, more importantly here, it provides the unique opportunity to align a linear racetrack section with a streak camera's entrance slit. This allows us to follow the evolution of plasma instabilities, i.e., localized ionization zones or spokes, as they travel along the racetrack. This report greatly extends our more limited and focused study on the structure and velocity of spokes [Anders and Yang, Appl. Phys. Lett. 111, 064103 (2017)]. Following recent plasma potential measurements [Panjan and Anders, J. Appl. Phys. 121, 063302 (2017)], we interpret optical emission information with localized electron heating. We confirm that for low direct current operation, spokes move in the -E ×B direction, and in the opposite direction in the high current mode. Streak images indicate slower spoke velocities near corners compared to spoke velocities in the straight sections of the racetrack. Spoke splitting and merging are observed supporting the interpretation that spoke motion represents a phase velocity of the region of greatest ionization and is not a motion of plasma. Fast camera investigations are supplemented by measurements of the energy distribution functions of ions emitted from the straight and curved regions of the racetrack, showing notable and reproducible differences.

On the Spatial Power Spectrum of the E x B Gradient Drift Instability in Ionospheric Plasma Clouds.

DTIC Science & Technology

1981-04-14

Perkins et al., 1973]. In reality, an artificially injected plasma cloud will, initially, be two- dimensional in the plane perpendicular to the magnetic...Motion of Artificial Ion Clouds in the Upper Atmosphere, Planet. Space Sci., 15, 1, 1967. Kelley, M.C., K.D. Baker, and J.C. Ulwick, Late Time Barium...42960 COMiANDER WORLOA’AY POS’AL CENTER J.S. ARMY MISSILE INTELLIGENCE AGENCY "’OS ANGELES, CA. 90009 REDSTONE ARSENAL, AL 35809 OICY ATTN CODE 52 0ICY

Correction to: Associations between attention-deficit/hyperactivity disorder and autoimmune diseases are modified by sex: a population-based cross-sectional study.

PubMed

Hegvik, Tor-Arne; Instanes, Johanne Telnes; Haavik, Jan; Klungsøyr, Kari; Engeland, Anders

2018-05-01

The article "Associations between attention-deficit/hyperactivity disorder and autoimmune diseases are modified by sex: a population-based cross-sectional study", written by Tor-Arne Hegvik, Johanne Telnes Instanes, Jan Haavik, Kari Klungsøyr and Anders Engeland, was originally published electronically on the publisher's internet portal (currently SpringerLink) on October 5, 2017 without open access due to an error by the Springer editorial office in the processing of this article. The authors had originally opted for open access.

A Systems Biology Strategy to Identify Molecular Mechanisms of Action and Protein Indicators of Traumatic Brain Injury

DTIC Science & Technology

2014-11-14

2 Xueping Yu,1 Bhaskar Dutta,1 Jacob D. Feala,1 Kara Schmid,2 Jitendra Dave,2 Gregory J . Tawa,1 Anders Wallqvist,1 and Jaques Reifman1* 1Department of...pathway.html), downloaded in December, 2011. KEGG, one of the largest and most widely used publicly available pathway databases, anno - tates pathways...Ansari MA, Roberts KN, Scheff SW. 2008b. A time course of contusion-induced oxidative stress and synaptic proteins in cortex in a rat model of TBI. J

Proceedings of the Smoke/Obscurants Symposium 5, Held at Harry Diamond Laboratories, Adelphi, Maryland 28, 29, & 30 April, 1981. Volume 2

DTIC Science & Technology

1981-07-01

C-11. Cluttor Rejecti,, Techniques for Laser Semi-Active Missile Systems .................. 715 .H. F. Anders.n (MICOM), F. J. Polge ’UAHIi...Qriffin, J, A-25* Price, W. R. A-11PGriffith. P. N, A-4* Poleski, F. D-5PGuerin, M. C-16 Polge , R. J. C-11l xvii Proceedings Papers by Author...Sensors Directorate US Army Missile Laboratory US Army Missile Command Redstone Arsenal, Alabama 35898 ROBERT J. POLGE University of Alabama, Huntsville

Analysis Methods and Models for Small Unit Operations

DTIC Science & Technology

2006-07-01

wordt in andere studies ogebruikt orn a-an te geven welke op welke wijze operationele effectiviteit kan worden gekwalificeerd en gekwanuificeerd...the node ’Prediction’ is called a child of the node ’Success’ and the node ’Success’ is called a parent of the node ’Prediction’. Figure C.2 A simple...event A is a child of event B and event B is a child of event C ( C -- B -- A). The belief network or influence diagram has to be a directed network

Beslisbevoegdheden en Verantwoordelijkheden van de Uitgestegen Soldaat. Deel A: Verplaatsen van Beslisbevoegdheden (Authority and Responsibility of the Dismounted Soldier. Part A. Empowering the Dismounted Soldier)

DTIC Science & Technology

2007-04-01

en verantwoordelijkheden van de uitgestegen soldaat Deel A: verplaatsen van beslisbevoegdheden Datumn april 2007 Auteur (s) R. de Bruin ITE. van Bernmel...Admiraal, Bureau SMP Auteur (s) R. de Bruin Program maleider Projectleider I.E. van Bemnmel dr. W.A. Lotens, A.J. van Vliet, A.J. van Vijet TNO Defensie en...Leadership Theory en wordt relevant geacht voor de ontvangers van aanvullende beslisbevoegdheden. 2.1.3 Het oogmerk van de hogere commandant Een ander

Volcanism and soil mercury on Mars - Consequences for terrestrial microorganisms

NASA Technical Reports Server (NTRS)

Siegel, B. Z.; Siegel, S. M.

1978-01-01

An earth-Mars depletion formula proposed by Anders and Owen for volatiles is used to calculate a range of putative Hg levels for Martian volcanic soils based upon analyzed samples from Hawaii. The range is about 50-150 microgram per kg. When applied either in conventional or special media (e.g., basalt powder), these levels of Hg are effective inhibitors of the growth of earth microorganisms. Taken together with other hostile chemical and physical factors, volcanic toxicants would appear to provide a further deterrent to the accidental establishment of terrestrial microbiota on Mars.

PORTRAIT - ASTRONAUT GROUP - NEWLY-SELECTED - MSC

NASA Image and Video Library

1963-10-18

S63-18765 (October 1963) --- These fourteen pilots have been assigned to begin training for astronaut positions with the National Aeronautics and Space Administration (NASA). Front row, from the left, Edwin E. Aldrin Jr., William A. Anders, Charles A. Bassett II, Alan L. Bean, Eugene A. Cernan and Roger B. Chaffee. Back row, from the left, Michael Collins, Walter Cunningham, Donn F. Eisele, Theodore C. Freeman, Richard F. Gordon Jr., Russell L. Scweickart, David R. Scott and Clifton C. Williams Jr. Photo credit: NASA or National Aeronautics and Space Administration

Evaluatie Kennistechnologische Ondersteuning bij Diagnose van SEWACO systemen (Projectmanagementplan) (Evaluation of Knowledge Technological Support for Diagnosis of SEWACO Systems (Project Management Plan)

DTIC Science & Technology

1991-08-01

diagnos van SE WACO systmnen/ AD-A245 424111 1fl1,l Niets uit deze uitgave mag warden vermenigvuldligd en/of oPenbaar gemaakt door middel van druk...fotakopie. microfilm of op welks andere whlze dan ook, zonder voorafgaande toeslemming van TNO. Hot ter inzage geven van het TNO-rapport aan direct...belanghebbenden is tegestaan. HYP. vanl OC dt Indian dit rapport in opdracht ward uitgebracht, wordt voor de, rechten en verpiichtingen van opdrachtgever en

User Manual PIRATE Model, Release Beta 1.0. (Handleiding PIRATE model, versie Beta 1.0)

DTIC Science & Technology

1998-01-01

Beperkingen van PIRATE 40 9 . Conclusies en aanbevelingen 41 10. Referenties 42 11 . Ondertekening 43 TNO-rapport FEL-97-A285 Inleiding Bij maritieme...Inhoud Inleiding 7 1.1 Doel van PIRATE 7 1.2 Werking van PIRATE 8 1.3 Opbouw van de handleiding 8 2. Bediening van PIRATE 9 2.1 Systeemvereisten 10...2.2 Installatie 10 2.3 Bediening van de gebruikersinterface 11 2.4 Gebruiken van de figuren in andere programmes 15 3. Radars, radars in PIRATE

Quantum annealing for the number-partitioning problem using a tunable spin glass of ions

PubMed Central

Graß, Tobias; Raventós, David; Juliá-Díaz, Bruno; Gogolin, Christian; Lewenstein, Maciej

2016-01-01

Exploiting quantum properties to outperform classical ways of information processing is an outstanding goal of modern physics. A promising route is quantum simulation, which aims at implementing relevant and computationally hard problems in controllable quantum systems. Here we demonstrate that in a trapped ion setup, with present day technology, it is possible to realize a spin model of the Mattis-type that exhibits spin glass phases. Our method produces the glassy behaviour without the need for any disorder potential, just by controlling the detuning of the spin-phonon coupling. Applying a transverse field, the system can be used to benchmark quantum annealing strategies which aim at reaching the ground state of the spin glass starting from the paramagnetic phase. In the vicinity of a phonon resonance, the problem maps onto number partitioning, and instances which are difficult to address classically can be implemented. PMID:27230802

VizieR Online Data Catalog: Seismology and spectroscopy of CoRoGEE red giants (Anders+, 2017)

NASA Astrophysics Data System (ADS)

Anders, F.; Chiappini, C.; Rodrigues, T. S.; Miglio, A.; Montalban, J.; Mosser, B.; Girardi, L.; Valentini, M.; Noels, A.; Morel, T.; Johnson, J. A.; Schultheis, M.; Baudin, F.; de Assis Peralta, R.; Hekker, S.; Themessl, N.; Kallinger, T.; Garcia, R. A.; Mathur, S.; Baglin, A.; Santiago, B. X.; Martig, M.; Minchev, I.; Steinmetz, M.; da Costa, L. N.; Maia, M. A. G.; Allende Prieto, C.; Cunha, K.; Beers, T. C.; Epstein, C.; Garcia Perez, A. E.; Garcia-Hernandez, D. A.; Harding, P.; Holtzman, J.; Majewski, S. R.; Meszaros, Sz.; Nidever, D.; Pan, K.; Pinsonneault, M.; Schiavon, R. P.; Schneider, D. P.; Shetrone, M. D.; Stassun, K.; Zamora, O.; Zasowski, G.

2016-08-01

For the 606 successfully observed stars, asteroseismic parameters from CoRoT, spectroscopic data from APOGEE (SDSS DR12), wide-band photometry from OBSCAT, APASS, SDSS, 2MASS, and WISE are presented. Additional information from the EXODAT archive, stellar parameters from PARAM (Rodrigues et al. 2014MNRAS.445.2758R), cross-matches to the APOGEE red-clump catalogue (Bovy et al. 2014ApJ...790..127B), the UCAC-4 catalogue (Zacharias et al., 2013, Cat. I/322), and derived stellar kinematics are also included. (2 data files).

The matrices of unequilibrated ordinary chondrites - Implications for the origin and history of chondrites

NASA Technical Reports Server (NTRS)

Huss, G. R.; Keil, K.; Taylor, G. J.

1981-01-01

The matrices of 16 unequilibrated chondrites were examined by optical microscopy, an electron microprobe, and a scanning electron microscope. The fine-grained, opaque, silicate matrix of type 3 unequilibrated chondrites was compositionally, mineralogically, and texturally different from the chondrules and their fragments; it may be the low temperature condensate proposed by Larimer and Anders (1967, 1970). Each meteorite has been metamorphosed by a combination of processes including thermal metamorphism and the passage of shock waves; the appearance of each chondrite results from the temperature and pressure conditions which formed it, and subsequent metamorphic alterations.

Law & psychiatry: imposed insanity defenses and political crimes.

PubMed

Appelbaum, Paul S

2013-01-01

Anders Breivik's murder of 77 people in Norway in 2011 led to an unusual clash of interests. With conflicting psychiatric reports regarding his sanity, prosecutors argued that Breivik should be found not guilty by reason of insanity, whereas the defense strongly maintained that he was sane and responsible for his actions. Imposing an insanity defense on an unwilling defendant pits societal interests in fair adjudications against the right of defendants to control their defense. For crimes with political motivations, an imposed insanity verdict discredits the perpetrator and may distract the public from the threats posed by extreme political views.

Digitale Transformation, aber wie? - Von der Spielwiese zur Umsetzungsplanung

NASA Astrophysics Data System (ADS)

Kaiser, Thomas

Es besteht wohl kaum Anlass zur Annahme, dass die seit Jahrzehnten etablierten Markt- und Technologiestrukturen der Energiewirtschaft sich nicht in einem radikalen Ablöseprozess mit Gewinnern und Verlierern befinden. Aber Vorsicht - vordergründig bereits verloren erscheinende Geschäftsmodelle erfahren im Zuge der Digitalisierung einerseits noch intensiveren Wettbewerbsdruck, können aber andererseits von diesem "technologischen Jungbrunnen" profitieren, um verlorenes Terrain zurückzugewinnen. Im folgenden Kapitel wird ein Managementzyklus aufgezeigt, der in Anlehnung an die bereits erfolgreiche Implementierung digitaler R/Evolutionen anderer Branchen aufzeigt, wie die Geschäftsleitung systematisch kostenbewusst und zielorientiert die Digitalisierung umsetzen kann.

Unternehmen in der Verantwortung. Regionaler Strukturwandel anders

NASA Astrophysics Data System (ADS)

Kost, Klaus; Weingarten, Jörg

2016-03-01

Factory closures, relocations and extensive measures to reduce personnel have consequences far beyond the affected employees - the social and economic coherence of the location and region are often negatively affected, too. This presents an interesting and important field for economic and applied geography. Apart from the development and evaluation of concepts of instruments of regional development, geographers can discuss and conceive options and obstacles for compensation and replacement measures after corporate restructuring. This text discusses structural and individual opportunities and obstacles in implementing company-induced economic development measures in the wider context of the corporate responsibility debate.

Anders Johan Lexell's Role in the Determination of the Solar Parallax

NASA Astrophysics Data System (ADS)

Sten, Johan Carl-Erik; Aspaas, Per Pippin

2013-05-01

Anders Johan Lexell (1740-1784) was a mathematician who gained considerable recognition for his scientific achievements during the century of Enlightenment. Born and educated in Abo/Turku in the Finnish part of the Swedish Realm, he was invited as an assistant and collaborator of Leonhard Euler at the Imperial Academy of Sciences in Saint Petersburg in 1768. After Euler's death in 1783 he inherited his mentor's chair and became professor of mathematics at the Petersburg Academy of Sciences, but survived only a year in this office. One of Lexell's first tasks in Saint Petersburg was to assist in the calculations involved in the Venus transit project of 1769. Under Euler's supervision, Lexell formulated a system of modeling equations involving the whole bulk of observation data obtained from all over the world. Thus, by searching (manually) the best estimate of the parallax with respect to all available measurements made of the Venus transit simultaneously, he anticipated later statistical modeling methods. The usual method at the time consisted of juxtaposing a pair of measurements at a time and taking a mean value of all the parallax values obtained in this way. What had started as an innocent, purely academic attempt to establish the solar parallax, soon escalated into a heated controversy of international dimensions. The roles played by Jerome de Lalande in Paris and Maximilian Hell in Vienna in this controversy are well known; Lexell's role less so. Our analysis has two aims. First, we elucidate Lexell's place in the international solar parallax controversy by making use of his published works as well as surviving parts of his correspondence. Second, we present the method used by Lexell and analyze his way of calculating the solar parallax.

Effect of the aqueous extract of Justicia insularis T. Anders (Acanthaceae) on ovarian folliculogenesis and fertility of female rats.

PubMed

Telefo, Phelix Bruno; Tagne, Simon Richard; Koona, Olga Elodie Sandrine; Yemele, Didiane M; Tchouanguep, Félicité M

2012-01-01

Justicia insularis T. Anders (Acanthaceae) is a medicinal plant whose leaves and those of three other plants are mixed for the preparation of a concoction used to improve fertility and to reduce labour pains in women of the Western Region of Cameroon. Previous studies have demonstrated the inducing potential on ovarian folliculogenesis and steroidogenesis of the aqueous extract of the leaf mixture (ADHJ) of four medicinal plants (Aloe buettneri, Dicliptera verticillata, Hibiscus macranthus and Justicia insularis) among which the later represented the highest proportion. This study was aimed at evaluating the ovarian inducing potential of J. insularis in immature female rats. Various doses of the aqueous extract of J. insularis were daily and orally given, for 20 days, to immature female rats distributed into four experimental groups of twenty animals each. At the end of the experimental period some biochemical and physiological parameters of ovarian function were assayed. The administration of the aqueous extract of Justicia insularis significantly induced an early vaginal opening in all treated groups (P < 0.001) as well as an increase (at doses of 50 or 100 mg/kg) in the number of hemorrhagic points, Corpus luteum, implantation sites, ovarian weight, uterine and ovarian proteins. Ovarian cholesterol level (P < 0.05) significantly decreased in animals treated with the lowest dose (12.5 mg/kg). The evaluation of the toxicological effects of the extract on pregnancy showed that it significantly increased pre- and post-implantation losses, resorption index and decreased the rate of nidation as well as litter's weight. These results suggest that the aqueous extract of Justicia insularis induces ovarian folliculogenesis thus justifying its high proportion in the leaf mixture of ADHJ.

Pox 186: An ultracompact galaxy with dominant ionized gas emission

NASA Astrophysics Data System (ADS)

Guseva, N. G.; Papaderos, P.; Izotov, Y. I.; Noeske, K. G.; Fricke, K. J.

2004-07-01

We present a ground-based optical spectroscopic and HST U, V, I photometric study of the blue compact dwarf (BCD) galaxy Pox 186. It is found that the emission of the low-surface brightness (LSB) component in Pox 186 at radii ⪉3 arcsec (⪉270 pc in linear scale) is mainly gaseous in origin. We detect Hα emission out to radii as large as 6 arcsec. At radii ⪆3 arcsec the light of the LSB component is contaminated by the emission of background galaxies complicating the study of the outermost regions. The surface brightness distribution in the LSB component can be approximated by an exponential law with a scale length α ⪉ 120 pc. This places Pox 186 among the most compact dwarf galaxies known. The derived α is likely to be an upper limit to the scale length of the LSB component because of the strong contribution of the gaseous emission. The oxygen abundance in the bright H II region derived from the 4.5 m Multiple Mirror Telescope (MMT) and 3.6 m ESO telescope spectra are 12 + log (O/H) = 7.76 ± 0.02 and 7.74 ± 0.01 (˜Z⊙/15), respectively, in accordance with previous determinations. The helium mass fractions found in this region are Y = 0.248 ± 0.009 (MMT) and Y = 0.248 ± 0.004 (3.6 m) suggesting a high primordial helium abundance. The MMT Observatory is a joint facility of the Smithsonian Institution and the University of Arizona. Based on observations collected at the European Southern Observatory, Chile, ESO program 71.B-0032(A). 12+\\log(O/H)⊙ = 8.92 (Anders & Grevesse \\cite{Anders89}).

Human Factors Analysis of Two Prototype Army Maintenance Training and Evaluation Simulation System (AMTESS) Devices. Appendixes

DTIC Science & Technology

1984-10-01

ACE ’»>••» 0<i« t»».!-«*) REPORT DOCUMENTATION PAGE READ INSTRUCTIONS BEFORE COMPLETING FORM 1 . REPOOT NUMlE* Research Note 84-126 2. CQVT...Criswell, Robert W.,Swezey, John A. Allen, Robert T. Hays 1 . CONTRACT OR GRANT NUMtERf; MDA 903-79-C-0177 i. RER’ORWINC ORGANIZATION NAME AND...er i H«V •■ it OMOLITC i/W 01OMP 414.4401 1 UNCLASSIFIED »CURITY CkASSiriCATlOM *» TMIt » A«C f"»«i »«• ***-**> Ä This volume contair.3 the

Hadoop-BAM: directly manipulating next generation sequencing data in the cloud

PubMed Central

Niemenmaa, Matti; Kallio, Aleksi; Schumacher, André; Klemelä, Petri; Korpelainen, Eija; Heljanko, Keijo

2012-01-01

Summary: Hadoop-BAM is a novel library for the scalable manipulation of aligned next-generation sequencing data in the Hadoop distributed computing framework. It acts as an integration layer between analysis applications and BAM files that are processed using Hadoop. Hadoop-BAM solves the issues related to BAM data access by presenting a convenient API for implementing map and reduce functions that can directly operate on BAM records. It builds on top of the Picard SAM JDK, so tools that rely on the Picard API are expected to be easily convertible to support large-scale distributed processing. In this article we demonstrate the use of Hadoop-BAM by building a coverage summarizing tool for the Chipster genome browser. Our results show that Hadoop offers good scalability, and one should avoid moving data in and out of Hadoop between analysis steps. Availability: Available under the open-source MIT license at http://sourceforge.net/projects/hadoop-bam/ Contact: matti.niemenmaa@aalto.fi Supplementary information: Supplementary material is available at Bioinformatics online. PMID:22302568

A 850 GHz SIS receiver employing silicon micro-machining technology

NASA Technical Reports Server (NTRS)

Kooi, J. W.; Pety, J.; Schaffer, P. L.; Phillips, T. G.; Bumble, B.; LeDuc, H. G.; Walker, C. K.

1996-01-01

A 850 GHz superconductor-insulator-superconductor (SIS) heterodyne receiver which uses a radiofrequency tuned niobium tunnel junction fabricated on a 1 micron thick silicon nitrate membrane, is reported. From video and heterodyne measurements, it was calculated that the niobium film loss in the radiofrequency matching network is about 6.8 dB at 822 GHz. These results are approximately a factor of two higher than the theoretical loss predicted by the Mattis-Bardeen theory in the extreme anomalous limit. The junction design and the receiver configuration are described, including the mixer block, the membrane construction and the cooled optics. The performance tests using a Fourier transform spectrometer to measure the response of the radiofrequency matching network, and the SIS simulations of the receiver response to cold and hot loads, the infrared noise contribution and the overall mixer conversion efficiency, are reported. It is concluded that the receiver response is limited by the absorption loss in the radiofrequency matching network.

Exploring the performance of thin-film superconducting multilayers as kinetic inductance detectors for low-frequency detection

NASA Astrophysics Data System (ADS)

Zhao, Songyuan; Goldie, D. J.; Withington, S.; Thomas, C. N.

2018-01-01

We have solved numerically the diffusive Usadel equations that describe the spatially varying superconducting proximity effect in Ti-Al thin-film bi- and trilayers with thickness values that are suitable for kinetic inductance detectors (KIDs) to operate as photon detectors with detection thresholds in the frequency range of 50-90 GHz. Using Nam’s extension of the Mattis-Bardeen calculation of the superconductor complex conductivity, we show how to calculate the surface impedance for the spatially varying case, and hence the surface impedance quality factor. In addition, we calculate energy-and spatially-averaged quasiparticle lifetimes at temperatures well-below the transition temperature and compare to calculation in Al. Our results for the pair-breaking threshold demonstrate differences between bilayers and trilayers with the same total film thicknesses. We also predict high quality factors and long multilayer-averaged quasiparticle recombination times compared to thin-film Al. Our calculations give a route for designing KIDs to operate in this scientifically-important frequency regime.

Age and paleoenvironment of the imperial formation near San Gorgonio Pass, Southern California

USGS Publications Warehouse

McDougall, K.; Poore, R.Z.; Matti, J.

1999-01-01

Microfossiliferous marine sediments of the Imperial Formation exposed in the Whitewater and Cabazon areas, near San Gorgonio Pass, southern California, are late Miocene in age and were deposited at intertidal to outer neritic depths, and possibly upper bathyal depths. A late Miocene age of 7.4 to >6.04 Ma is based on the ranges of age-diagnostic benthic foraminifers (Cassidulina delicata and Uvigerina peregrina), planktic foraminifers (Globigerinoides obliquus, G. extremus, and Globigerina nepenthes; zones N17-N19), and calcareous nannoplankton (Discoaster brouweri, D. aff. D. surculus, Reticulofenestra pseudoumbilicata, Sphenolithus abies, and S. neoabies; zones CN9a-CN11) coupled with published K/Ar dates from the underlying Coachella Formation (10.1 ?? 1.2 Ma; Peterson, 1975) and overlying Painted Hill Formation (6.04 ?? 0.18 and 5.94 ?? 0.18 Ma; J. L. Morton in Matti and others, 1985 and Matti and Morton, 1993). Paleoecologic considerations (sea-level fluctuations and paleotemperature) restrict the age of the Imperial Formation to 6.5 through 6.3 Ma. Benthic foraminiferal assemblages indicate that the Imperial Formation in the Whitewater and Cabazon sections accumulated at inner neritic to outer neritic (0-152 m) and possibly upper bathyal (152-244 m) depths. Shallowing to inner neritic depths occurred as the upper part of the section was deposited. This sea-level fluctuation corresponds to a global highstand at 6.3 Ma (Haq and others, 1987). Planktic foraminifers suggest an increase in surface-water temperatures upsection. A similar increase in paleotemperatures is interpreted for the North Pacific from 6.5 to 6.3 Ma (warm interval W10 of Barron and Keller, 1983). Environmental contrasts between the Whitewater and Cabazon sections of the Imperial Formation provide evidence for right-lateral displacements on the Banning fault, a late Miocene strand of the San Andreas fault system. The Cabazon section lies south of the Banning fault, and has been displaced west relative to the Whitewater sections. The Cabazon section was deposited at greater depths, suggesting that it accumulated farther offshore than the Whitewater section. If the Salton Trough was a southward-opening, elongated northwest-southeast basin similar to the modern Gulf of California, the Cabazon sequence probably has been displaced right-laterally from a position farther southeast of the Whitewater sequence. This relation requires late Miocene displacements greater than the present 12 km cross-fault separation between the two Imperial sections in the San Gorgonio Pass area.

Apollo 8 Mission Report

NASA Technical Reports Server (NTRS)

1969-01-01

Postflight analysis of Apollo 8 mission. Apollo 8 was the second manned flight in the program and the first manned lunar orbit mission. The crew were Frank Borman, Commander; James A. Lovell, Command Module Pilot; and William A. Anders, Lunar Module Pilot. The Apollo 8 space vehicle was launched on time from Kennedy Space Center, Florida, at 7:51:00 AM, EST, on December 21, 1968. Following a nominal boost phase, the spacecraft and S-IVB combination was inserted - into a parking orbit of 98 by 103 nautical miles. After a post-insertion checkout of spacecraft systems, the 319-second translunar injection maneuver was initiated at 2:50:37 by reignition of the S-IVB engine.

Das andere Zuhause. Ortsbezüge hochqualifizierter Migranten

NASA Astrophysics Data System (ADS)

Plöger, Jörg; Günther, Florian

2016-12-01

Cities are increasingly addressing high-skilled migrants. Our contribution examines the factors that shape how this group relates to places and why cities provide different conditions for this. We draw on empirical data from an explorative case study with highly qualified migrants in the university city of Münster. First, we look at the place ties at the new place of residence and thereby focus on their local social networks and their sense of belonging. Second, we turn to the place-specific characteristics, in particular the role of "connections" and "urban opportunity structures". Based on our findings we discuss how urban policy-making may influence the place attachment of this desired group.

The Breivik controversy: politics, terrorism and psychiatry.

PubMed

Tietze, Tad

2014-08-01

To examine and analyse the controversy over psychiatric aspects of the case of Norwegian far right mass murderer Anders Behring Breivik. Because of a basic acceptance of methodological individualism and scientific positivism, mainstream psychiatry is currently ill suited to being broadly applied to the spheres of politics and political violence. Rather than jettison psychiatric insights in such cases, the choices facing the profession are either to accept the narrowness of its utility or to work towards a theoretical framework that sees the individual psyche as socially embedded rather than as socially constitutive, and psychiatric science itself as socially constructed and hence inescapably value-laden. © The Royal Australian and New Zealand College of Psychiatrists 2014.

Aphrodisiac and spermatogenic potential of alkaloidal fraction of Hygrophila spinosa T. Ander in rats.

PubMed

Vyas, Niraj Y; Raval, Manan A

2016-12-24

Seeds of Hygrophila spinosa T. Ander (Acanthaceae) are traditionally used as aphrodisiac and spermatogenic in Indian System of medicine. Preliminary phytochemical screening of plant revealed the presence of alkaloids in seeds. As, alkaloidal fractions of several plants showed aphrodisiac and spermatogenic potential, set of experiments were designed to assess alkaloid enriched fraction of seeds of the plant for spermatogenic and aphrodisiac activity using in vitro and in vivo methods. Alkaloid enriched fraction was prepared and assessed for spermatogenic activity using isolated rat Leydig cells in vitro. The fraction was further evaluated in vivo for spermatogenic and aphrodisiac potential using rat as an experimental animal. Increase in weight of reproductive organs, biochemical evaluation of selected parameters, histological studies of testes and sexual behavioral studies were selected as evaluation parameters for in vivo studies. Isolated rat Leydig cells treated with the fraction showed increased amount of testosterone present in culture media (14.7µg/ml) as compared to that of control (0.8µg/ml). Results of in vivo studies showed increase in serum testosterone level in treated animals (50mg/kg) by (115%), increase in weight of testes (8.0%) as compared to control. Marked improvement in testis histo-architecture of rats evident preliminarily by observing overcrowding of spermatozoa in enlarged lumen of seminiferous tubules in animals treated with testosterone and test fraction. Sertoli cells in treated animals were enlarged with highly granulated cytoplasm. Leydig cells also showed enlarged nucleus and darkly stained cytoplasm as compared to control. Mounting behavior of test animals improved, while latency period was decreased, as observed in behavioral studies. The set studies confirmed the ability of the fraction to stimulate Leydig cells and increased serum testosterone level. Increased testosterone level might be responsible for higher number of spermatozoa in testicular lumen as seen in testicular histology as well as increased libido as observed in behavioral studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Memory disorders in probable Alzheimer's disease: the role of hippocampal atrophy as shown with MRI.

PubMed Central

Deweer, B; Lehéricy, S; Pillon, B; Baulac, M; Chiras, J; Marsault, C; Agid, Y; Dubois, B

1995-01-01

Magnetic resonance based volumetric measures of hippocampal formation, amygdala (A), caudate nucleus (CN), normalised for total intracranial volume (TIV), were analysed in relation to measures of cognitive deterioration and specific features of memory functions in 18 patients with probable Alzheimer's disease. Neuropsychological examination included the mini mental state examination (MMSE), the Mattis dementia rating scale (DRS), tests of executive functions, assessment of language abilities and praxis, the Wechsler memory scale (WMS), the California verbal learning test (CVLT) and the Grober and Buschke test. The volume of the hippocampal formation (HF/TIV) was correlated with specific memory variables: memory quotient and paired associates of the WMS; intrusions and discriminability at recognition for the Grober and Buschke test. By contrast, except for intrusions, no correlations were found between memory variables and the volume of amygdala (A/TIV). No correlations were found between the volume of caudate nuclei (CN/TIV) and any neuropsychological score. The volume of the hippocampal formation was therefore selectively related to quantitative and qualitative aspects of memory performance in patients with probable Alzheimer's disease. Images PMID:7745409

Filling constraints for spin-orbit coupled insulators in symmorphic and nonsymmorphic crystals

PubMed Central

Watanabe, Haruki; Po, Hoi Chun; Vishwanath, Ashvin; Zaletel, Michael

2015-01-01

We determine conditions on the filling of electrons in a crystalline lattice to obtain the equivalent of a band insulator—a gapped insulator with neither symmetry breaking nor fractionalized excitations. We allow for strong interactions, which precludes a free particle description. Previous approaches that extend the Lieb–Schultz–Mattis argument invoked spin conservation in an essential way and cannot be applied to the physically interesting case of spin-orbit coupled systems. Here we introduce two approaches: The first one is an entanglement-based scheme, and the second one studies the system on an appropriate flat “Bieberbach” manifold to obtain the filling conditions for all 230 space groups. These approaches assume only time reversal rather than spin rotation invariance. The results depend crucially on whether the crystal symmetry is symmorphic. Our results clarify when one may infer the existence of an exotic ground state based on the absence of order, and we point out applications to experimentally realized materials. Extensions to new situations involving purely spin models are also mentioned. PMID:26604304

Thomas Graham Brown (1882–1965): Behind the Scenes at the Cardiff Institute of Physiology

PubMed Central

Jones, J. Gareth; Tansey, E.M. (Tilli); Stuart, Douglas G.

2011-01-01

Thomas Graham Brown undertook seminal experiments on the neural control of locomotion between 1910 and 1915. Although elected to the Royal Society in 1927, his locomotion research was largely ignored until the 1960s when it was championed and extended by the distinguished neuroscientist, Anders Lundberg. Puzzlingly, Graham Brown's published research stopped in the 1920s and he became renowned as a mountaineer. In this article, we review his life and multifaceted career, including his active neurological service in WWI. We outline events behind the scenes during his tenure at Cardiff's Institute of Physiology in Wales, UK, including an interview with his technician, Terrence J. Surman, who worked in this institute for over half a century.

Dürre, Waldbrände, gravitative Massenbewegungen und andere klimarelevante Naturgefahren

NASA Astrophysics Data System (ADS)

Glade, Thomas; Hoffmann, Peter; Thonicke, Kirsten

Klimarelevante Naturgefahren sind auf vielfältige Faktoren zurückzuführen, deren Zusammenwirken in der Gesamtheit betrachtet werden muss. Die vorbereitenden, auslösenden und kontrollierenden Faktoren werden in unterschiedlichster Weise vom Klimawandel beeinflusst. Die Autoren beschreiben beobachtete Trends und Projektionen zu Dürre, Waldbränden, gravitativen Massenbewegungen (Muren, Fels- und Bergstürze, Hangrutschungen) und Schneelawinen sowie das Zusammenspiel der unterschiedlichen Ursachen. Sie diskutieren darüber hinaus, welche der Veränderungen in der Häufigkeit oder Stärke von Naturgefahren tatsächlich ausschließlich dem Klimawandel zuzuschreiben sein könnten und welche Anteile hierbei der direkte menschliche Einfluss hat und konstatieren, dass eine eindeutige Trennung häufig nicht vollzogen werden kann.

At a Loss for Words: Nosological Impotence in the Search for Justice.

PubMed

Weiss, Kenneth J

2016-03-01

The assessment and trial of Norwegian mass-murderer Anders Breivik, including disparate opinions about his sanity, raise questions about distinguishing "bad" from "mad." Although he was ultimately found criminally responsible, the tenacity and pervasiveness of his beliefs suggested delusional thinking. The author reflects on the difficulty psychiatrists have with nomenclature generally and on the application of imprecise classification to criminal justice. Ideally, a classification system should "carve nature at its joints." Barring that, psychiatry needs operational definitions to appreciate the differences between idiosyncratic, psychotic thinking, and shared subcultural beliefs or ideologies. The concept of extreme overvalued belief provides a basis for making this distinction, when applied in the criminal justice context. © 2016 American Academy of Psychiatry and the Law.

Kommunale Energieversorger als wesentliche Akteure der Digitalisierung - Strategien und Handlungsoptionen

NASA Astrophysics Data System (ADS)

Reiche, Katherina

Die Digitalisierung erfasst sämtliche Bereiche des Lebens und Wirtschaftens. Auch die Kommunalwirtschaft - insbesondere die kommunale Energiewirtschaft - sieht sich perspektivisch disruptiven Entwicklungen gegenüber. Stadtwerke haben bereits viele Herausforderungen erfolgreich gemeistert und stehen auch der Digitalisierung positiv gegenüber. Vielerorts gestalten kommunale Unternehmen den digitalen Wandel bereits aktiv mit. Dieser Artikel arbeitet die Assets kommunaler Unternehmen heraus und zeigt Strategien und Handlungsoptionen zum Umgang mit der digitalen Transformation für kommunale Energieversorgungsunternehmen auf. Dabei zeigt sich, dass das politische und regulatorische Umfeld für das positive Gelingen der Digitalisierung entscheidend sind. Kommunale Unternehmen benötigen die gleichen Marktzugangsbedingungen wie andere Akteure. Ferner profitieren kommunale Unternehmen von einigen Wettbewerbsvorteilen, etwa hohen Vertrauenswerten ihrer Kunden und umfangreiches Know-how im Datenmanagement.

The Breivik case and what psychiatrists can learn from it

PubMed Central

Melle, Ingrid

2013-01-01

In the afternoon of July 22, 2011, Norwegian Anders Behring Breivik killed 77 persons, many of them children and youths, in two separate events. On August 24, 2012, he was sentenced to 21 years in prison. Breivik went through two forensic evaluations: the first concluded that he had a psychotic disorder, thus being legally unaccountable, whereas the second concluded that he had a personality disorder, thus being legally accountable. This article first describes Breivik's background and his crimes. This is followed by an overview of the two forensic evaluations, their methods, contents and disagreements, and how these issues were handled by the court in the verdict. Finally, the article focuses on some lessons psychiatrists can take from the case. PMID:23471788

The Breivik case and what psychiatrists can learn from it.

PubMed

Melle, Ingrid

2013-02-01

In the afternoon of July 22, 2011, Norwegian Anders Behring Breivik killed 77 persons, many of them children and youths, in two separate events. On August 24, 2012, he was sentenced to 21 years in prison. Breivik went through two forensic evaluations: the first concluded that he had a psychotic disorder, thus being legally unaccountable, whereas the second concluded that he had a personality disorder, thus being legally accountable. This article first describes Breivik's background and his crimes. This is followed by an overview of the two forensic evaluations, their methods, contents and disagreements, and how these issues were handled by the court in the verdict. Finally, the article focuses on some lessons psychiatrists can take from the case. Copyright © 2013 World Psychiatric Association.

Fast lichtschnell durch die Stadt: Visualisierung relativistischer Effekte

NASA Astrophysics Data System (ADS)

Kraus, Ute; Borchers, Marc P.

2005-03-01

Eine Computersimulation ermöglicht es uns, mit annähernd Lichtgeschwindigkeit durch die Tübinger Fußgängerzone zu fahren. Was wir dabei sehen, ist verblüffend: Die Häuser vor uns rücken umso weiter in die Ferne, je mehr wir beschleunigen; gleichzeitig erscheinen die Hauskanten in unserer Nähe immer stärker gekrümmt. Der Grund für diese merkwürdigen Bilder ist die so genannte Aberration: Ein und derselbe Lichtstrahl hat für den fahrenden Beobachter eine andere Richtung als für denjenigen, der am Straßenrand steht. Dieser Effekt ist im Alltag klein. Wenn wir aber in der Simulation fast lichtschnell durch die Tübinger Altstadt rasen, ist er dramatisch groß.

Anomalous phonon behavior in superconducting CaKFe 4 As 4 : An optical study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Run; Dai, Yaomin; Xu, Bing

Here, the temperature dependence of ab-plane optical conductivity of CaKFe 4As 4 has been measured below and above its superconducting transition temperature T c≃35.5 K. In the normal state, analysis with the two-Drude model reveals a T-linear scattering rate for the coherent response, which suggests strong spin-fluctuation scattering. Below the superconducting transition, the optical conductivity below 120 cm –1 vanishes, indicating nodeless gap(s). The Mattis-Bardeen fitting in the superconducting state gives two gaps of Δ 1 ≃ 9 meV and Δ 2 ≃ 14 meV, in good agreement with recent angle-resolved photoemission spectroscopy (ARPES) results. In addition, around 255 cmmore » –1, we observe two different infrared-active Fe-As modes with obvious asymmetric lineshape, originating from strong coupling between lattice vibrations and spin or charge excitations. Considering a moderate Hund's rule coupling determined from spectral weight analysis, we propose that the strong fluctuations induced by the coupling between itinerant carriers and local moments may affect the phonon mode, and the electron-phonon coupling through the spin channel is likely to play an important role in the unconventional pairing in iron-based superconductors.« less

Anomalous phonon behavior in superconducting CaKFe 4 As 4 : An optical study

DOE PAGES

Yang, Run; Dai, Yaomin; Xu, Bing; ...

2017-02-08

Here, the temperature dependence of ab-plane optical conductivity of CaKFe 4As 4 has been measured below and above its superconducting transition temperature T c≃35.5 K. In the normal state, analysis with the two-Drude model reveals a T-linear scattering rate for the coherent response, which suggests strong spin-fluctuation scattering. Below the superconducting transition, the optical conductivity below 120 cm –1 vanishes, indicating nodeless gap(s). The Mattis-Bardeen fitting in the superconducting state gives two gaps of Δ 1 ≃ 9 meV and Δ 2 ≃ 14 meV, in good agreement with recent angle-resolved photoemission spectroscopy (ARPES) results. In addition, around 255 cmmore » –1, we observe two different infrared-active Fe-As modes with obvious asymmetric lineshape, originating from strong coupling between lattice vibrations and spin or charge excitations. Considering a moderate Hund's rule coupling determined from spectral weight analysis, we propose that the strong fluctuations induced by the coupling between itinerant carriers and local moments may affect the phonon mode, and the electron-phonon coupling through the spin channel is likely to play an important role in the unconventional pairing in iron-based superconductors.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morin, R

The Medical Physics community lost one of its prominent leaders in April, 2013 with the passing of Donald D. Tolbert, PhD. He received his Doctorate at the University of Kansas followed by post Doctoral training at Florida State University and the University of Wisconsin. He was Chief of Radiation Therapy Medical Physics at the University of Wisconsin Hospital for 7 years before relocating to Honolulu Hawaii, where he founded the consulting group Mid-Pacific Medical Physics. Don was a leader in both the AAPM and the ACR, chairing the Professional Council and the Commission on Medical Physics. He was active onmore » the AAPM Board of Directors and a member of the ACR Board of Chancellors. Dr. Tolbert's approach to the difficult problems of the times was admired and respected by colleagues in Medical Physics, Radiation Oncology, and Diagnostic Radiology. He always rose above the heated political rhetoric and led the discussion to higher ground. His wisdom was continually sought to solve complicated problems. Following retirement, he returned to homes in Kansas and Colorado, devoting his time to writing about coping with diabetes and providing support for Seniors in Beloit Kansas. Don is survived by his wife, Mattie, his 3 children and 5 grandchildren. He will be greatly missed.« less

[Multidisciplinary treatment in orthodontics].

PubMed

Oosterkamp, B C M; Kuijpers, M A R

2015-11-01

In deze editie van het NTvT neemt het thema ‘Multidisciplinaire aanpak in de orthodontie’ de lezer mee in de mogelijkheden van multidisciplinaire zorg vanuit een orthodontisch oogpunt. Tandheelkunde is niet meer uitsluitend gericht op preventie en behandeling van cariës. De gebitstoestand van zowel ­kinderen als volwassenen is de afgelopen 30 jaar namelijk sterk verbeterd. De cariës­ervaring is duidelijk afgenomen en mensen behouden steeds langer hun natuurlijke gebit. Daarnaast is een fraai uitziend en goed functionerend gebit steeds vanzelfsprekender geworden en zijn patiënten gemotiveerd hun gebit te behouden. Deze ontwikkelingen vragen ook van (mond)zorgverleners een andere kijk op de zorg. De tandheelkundige zorg betreft steeds meer integrale zorg met een multidisciplinair karakter waarbij ­verschillende disciplines samenwerken om in samenspraak met de patiënt tot een optimaal resultaat te komen.

Saturn Apollo Program

NASA Image and Video Library

1968-12-17

Apollo 8 crew members paused before the mission simulator during training for the first manned lunar orbital mission. Frank Borman, commander; James Lovell, Command Module (CM) pilot; and William Anders, Lunar Module (LM) pilot , were also the first humans to launch aboard the massive Saturn V space vehicle. Lift off occurred on December 21, 1968 and returned safely to Earth on December 27, 1968. The mission achieved operational experience and tested the Apollo command module systems, including communications, tracking, and life-support, in cis-lunar space and lunar orbit, and allowed evaluation of crew performance on a lunar orbiting mission. The crew photographed the lunar surface, both far side and near side, obtaining information on topography and landmarks as well as other scientific information necessary for future Apollo landings. All systems operated within allowable parameters and all objectives of the mission were achieved.

Chemical composition of Mars

NASA Technical Reports Server (NTRS)

Morgan, J. W.; Anders, E.

1979-01-01

The chemical composition of Mars is estimated from the cosmochemical model of Ganapathy and Anders (1974) with additional petrological and geophysical constraints. The model assumes that planets and chondrites underwent the same fractionation processes in the solar nebula, and constraints are imposed by the abundance of the heat-producing elements, U, Th and K, the volatile-rich component and the high density of the mantle. Global abundances of 83 elements are presented, and it is noted that the mantle is an iron-rich garnet wehrlite, nearly identical to the bulk moon composition of Morgan at al. (1978) and that the core is sulfur poor (3.5% S). The comparison of model compositions for the earth, Venus, Mars, the moon and a eucrite parent body suggests that volatile depletion correlates mainly with size rather than with radial distance from the sun.

Building-integrated photovoltaics: A case study

NASA Astrophysics Data System (ADS)

Kiss, G.; Kinkead, J.; Raman, M.

1995-03-01

In 1992, Kiss Cathcart Anders Architects performed a study for NREL on Building-Integrated Photovoltaics (BIPV) issues as seen from the perspective of the building community. In general, the purpose of the study was to list major issues and potential applications; by it's nature it asked more questions than it answered. This second phase study was to produce quantitative data on the performance of specific BIPV systems. Only roof systems are evaluated. The energy performance, construction cost and simple payback for five different BIPV roof options are evaluated in six different locations: Oakland, New York, Miami, Phoenix, Chicago, and Cincinnati. The roof options evaluated include the following: single-glazed PV roof using glass-substrate PVs; double-glazed PV roof with insulating PV modules; ballasted roof-mounted system; sawtooth light monitor roof with indirect north daylighting; sawtooth roof with north light and active heat recovery.

Stein-Schere-Papier

NASA Astrophysics Data System (ADS)

Springborn, Boris

Wie gewinnt man im Spiel? Die Analyse von Strategien bei Gesellschaftsspielen ist ein Thema der mathematischen Spieltheorie. Mit ihren Methoden kann man aber nicht nur Spiele wie Schach oder Skat untersuchen, sondern auch verschiedenste Konfliktsituationen, bei denen das Schicksal jedes einzelnen Akteurs nicht nur vom eigenen Verhalten abhängt, sondern auch vom Verhalten der anderen, die ebenso wie er versuchen, ein für sie selbst möglichst positives Ergebnis herauszuschlagen. Die Spieltheorie hat großen Einfluss in den Wirtschaftswissenschaften. Auch in der Psychologie, Soziologie, Biologie und der Militärwissenschaft findet sie Anwendung. In der folgenden Aufgabe geht es aber tatsächlich um ein Spiel, und zwar um ein sehr einfaches, das jeder kennt. Trotzdem ist die Lösung nicht ganz einfach, und wer sie findet, hat schon die eine oder andere grundlegende Idee der Spieltheorie verstanden.

Apollo 8 Commander Frank Borman Receives Presidential Call

NASA Technical Reports Server (NTRS)

1968-01-01

Apollo 8 Astronaut Frank Borman, commander of the first manned Saturn V space flight into Lunar orbit, accepted a phone call from the U.S. President Lyndon B. Johnson prior to launch. Borman, along with astronauts William Anders, Lunar Module (LM) pilot, and James Lovell, Command Module (CM) pilot, launched aboard the Apollo 8 mission on December 21, 1968 and returned safely to Earth on December 27, 1968. The mission achieved operational experience and tested the Apollo command module systems, including communications, tracking, and life-support, in cis-lunar space and lunar orbit, and allowed evaluation of crew performance on a lunar orbiting mission. The crew photographed the lunar surface, both far side and near side, obtaining information on topography and landmarks as well as other scientific information necessary for future Apollo landings. All systems operated within allowable parameters and all objectives of the mission were achieved.

An atlas of Mars sedimentary rocks as seen by HiRISE

USGS Publications Warehouse

Beyer, Ross; Stack, Kathryn M.; Griffes, Jennifer L.; Milliken, Ralph E.; Herkenhoff, Ken E.; Byrne, Shane; Holt, John W.; Grotzinger, John P.; Grotzinger, John P.; Milliken, Ralph E.

2012-01-01

Photography in space has provided its own bounty. Who can forget the ӿrst image of Earthrise taken by astronaut William Anders in 1968 from Apollo 8; the solemnity of the ӿrst photos of the surface of the Moon from the Apollo 11astronauts; and the startling discovery of the tallest mountain in the solar system (Olympus Mons) on the surface of Mars in images sent from Mariner 9? The images from Mariner 9 also allowed for a game-changing discovery. Earlier, based on very limited Mariner 4 data that covered less than 10% of the planet's surface, Chapman et al. (1968) speculated that “If substantial aqueous erosion features—such as river valleys— were produced during earlier epochs of Mars, we should not expect any trace of them to be visible on the Mariner

Apollo 8 Astronaut James Lovell On Phone With President Johnson

NASA Technical Reports Server (NTRS)

1968-01-01

Apollo 8 Astronaut James Lovell, Command Module (CM) pilot of the first manned Saturn V space flight into Lunar orbit, accepted a phone call from the U.S. President Lyndon B. Johnson prior to launch. Lovell, along with astronauts William Anders, Lunar Module (LM) pilot, and Frank Borman, commander, launched aboard the Apollo 8 mission on December 21, 1968 and returned safely to Earth on December 27, 1968. The mission achieved operational experience and tested the Apollo command module systems, including communications, tracking, and life-support, in cis-lunar space and lunar orbit, and allowed evaluation of crew performance on a lunar orbiting mission. The crew photographed the lunar surface, both far side and near side, obtaining information on topography and landmarks as well as other scientific information necessary for future Apollo landings. All systems operated within allowable parameters and all objectives of the mission were achieved.

Building-integrated photovoltaics: A case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kiss, G.; Kinkead, J.; Raman, M.

1995-03-01

In 1992, Kiss Cathcart Anders Architects performed a study for NREL on Building-Integrated Photovoltaics (BIPV) issues as seen from the perspective of the building community. In general, the purpose of the study was to list major issues and potential applications; by it`s nature it asked more questions than it answered. This second phase study was to produce quantitative data on the performance of specific BIPV systems. Only roof systems are evaluated. The energy performance, construction cost and simple payback for five different BIPV roof options are evaluated in six different locations: Oakland, New York, Miami, Phoenix, Chicago, and Cincinnati. Themore » roof options evaluated include the following: single-glazed PV roof using glass-substrate PVs; double-glazed PV roof with insulating PV modules; ballasted roof-mounted system; sawtooth light monitor roof with indirect north daylighting; sawtooth roof with north light and active heat recovery.« less

The genetics of music accomplishment: evidence for gene-environment correlation and interaction.

PubMed

Hambrick, David Z; Tucker-Drob, Elliot M

2015-02-01

Theories of skilled performance that emphasize training history, such as K. Anders Ericsson and colleagues' deliberate-practice theory, have received a great deal of recent attention in both the scientific literature and the popular press. Twin studies, however, have demonstrated evidence for moderate-to-strong genetic influences on skilled performance. Focusing on musical accomplishment in a sample of over 800 pairs of twins, we found evidence for gene-environment correlation, in the form of a genetic effect on music practice. However, only about one quarter of the genetic effect on music accomplishment was explained by this genetic effect on music practice, suggesting that genetically influenced factors other than practice contribute to individual differences in music accomplishment. We also found evidence for gene-environment interaction, such that genetic effects on music accomplishment were most pronounced among those engaging in music practice, suggesting that genetic potentials for skilled performance are most fully expressed and fostered by practice.

Uber Phosphorylierung im Licht

PubMed Central

Warburg, Otto

1962-01-01

Während bisher der Zusammenhang zwischen Dehydrierung und Phosphorylierung im Licht nur für die stöchiometrischen Chinonreactionen bewiesen worden war, ist nunmehr auch für die katalytischen Chinonreactionen, die aeroben wie die anaeroben, gezeigt worden, dass die Dehydrierung die Phosphorylierung bewirkt. Eine andere Phosphorylierung, als die Phosphorylierung durch Dehydrierung gibt es in den grünen Grana nicht. Natürlich entsteht nunmehr die Frage, welche Substanz das Substrat von Dehydrierung und Phosphorylierung ist. Da die Grana keine Dunkelatmung haben und deshalb im Dunkeln nicht phosphorylieren können, auch nicht nach Zusatz von Chinon, so muss das gesuchte Substrat im Licht entstehen; und da der Photolyt der Granareactionen eine Kohlensäureverbindung ist, so muss das gesuchte Substrat eine im Licht entstehende Kohlenstoffverbindung sein. Wegen der Gärungen und dem einzigen bisher bekannten chemischen Mechanismus der Phosphorylierung durch Dehydrierung (4) denkt man an Triosephosphat. Aber chemisch ist jeder Aldehyd möglich. PMID:14004907

Linnaeans outdoors: the transformative role of studying nature 'on the move' and outside.

PubMed

Hodacs, Hanna

2011-06-01

Travelling is an activity closely associated with Carolus Linnaeus (1707-1778) and his circle of students. This article discusses the transformative role of studying nature outdoors (turning novices into naturalists) in eighteenth-century Sweden, using the little-known journeys of Carl Bäck (1760-1776), Sven Anders Hedin (1750-1821) and Johan Lindwall (1743-1796) as examples. On these journeys, through different parts of Sweden in the 1770s, the outdoors was used, simultaneously, as both a classroom and a space for exploration. The article argues that this multifunctional use of the landscape (common within the Linnaean tradition) encouraged a democratization of the consumption of scientific knowledge and also, to some degree, of its production. More generally, the study also addresses issues of how and why science and scientists travel by discussing how botanical knowledge was reproduced and extended 'on the move', and what got senior and junior students moving.

Olfactory Deficit Detected by fMRI in Early Alzheimer’s Disease

PubMed Central

Wang, Jianli; Eslinger, Paul J.; Doty, Richard L.; Zimmerman, Erin K.; Grunfeld, Robert; Sun, Xiaoyu; Connor, James R.; Price, Joseph L.; Smith, Michael B.; Yang, Qing X.

2012-01-01

Alzheimer’s disease (AD) is accompanied by smell dysfunction, as measured by psychophysical tests. Currently it is unknown whether AD-related alterations in central olfactory system neural activity, as measured by functional magnetic resonance imaging (fMRI), are detectable beyond those observed in healthy elderly. Moreover, it is not known whether such changes are correlated with indices of odor perception and dementia. To investigate these issues, twelve early stage AD patients and thirteen non-demented controls underwent fMRI while being exposed to each of three concentrations of lavender oil odorant. All participants were administered the University of Pennsylvania Smell Identification Test (UPSIT), the Mini-Mental State Examination (MMSE), the Mattis Dementia Rating Scale-2 (DRS-2), and the Clinical Dementia Rating Scale (CDR). The Blood oxygen level-dependent (BOLD) signal at primary olfactory cortex (POC) was weaker in AD than in HC subjects. At the lowest odorant concentration, the BOLD signals within POC, hippocampus, and insula were significantly correlated with UPSIT, MMSE, DRS-2, and CDR scores. The BOLD signal intensity and activation volume within the POC increased significantly as a function of odorant concentration in the AD group, but not in the control group. These findings demonstrate that olfactory fMRI is sensitive to the AD-related olfactory and functional cognitive decline. PMID:20709038

Unprecedented quality factors at accelerating gradients up to 45 MVm -1 in niobium superconducting resonators via low temperature nitrogen infusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grassellino, A.; Romanenko, A.; Trenikhina, Y.

We report the finding of new surface treatments that permit to manipulate the niobium resonator nitrogen content in the first few nanometers in a controlled way, and the resonator fundamental Mattis-Bardeen surface resistance and residual resistance accordingly. In particular, we find surface infusion conditions that systematically a) increase the quality factor of these 1.3 GHz superconducting radio frequency (SRF) bulk niobium resonators, up to very high gradients; b) increase the achievable accelerating gradient of the cavity compared to its own baseline with state-of-the-art surface processing. Cavities subject to the new surface process have larger than two times the state ofmore » the art Q at 2K for accelerating fields > 35 MV/m. Moreover, very high accelerating gradients ~ 45 MV/m are repeatedly reached, which correspond to peak magnetic surface fields of 190 mT, among the highest measured for bulk niobium cavities. These findings open the opportunity to tailor the surface impurity content distribution to maximize performance in Q and gradients, and have therefore very important implications on future performance and cost of SRF based accelerators. They also help deepen the understanding of the physics of the RF niobium cavity surface.« less

Summary Report of Cable Aging and Performance Data for Fiscal Year 2014.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Celina, Mathias C.; Celina, Mathias C.; Redline, Erica Marie

2014-09-01

As part of the Light Water Reactor Sustainability Program, science - based engineering approaches were employed to address cable degradation behavior under a range of exposure environments. Experiments were conducted with the goal to provide best guidance for aged material states, remaining life and expected performance under specific conditions for a range of cable materials. Generic engineering tests , which focus on rapid accelerated aging and tensile elongation , were combined with complementar y methods from polymer degradation science. Sandia's approach, building on previous years' efforts, enabled the generation of some of the necessary data supporting the development of improvedmore » lifetime predictions models, which incorporate known material b ehaviors and feedback from field - returned 'aged' cable materials. Oxidation rate measurements have provided access to material behavior under low dose rate thermal conditions, where slow degradation is not apparent in mechanical property changes. Such da ta have shown aging kinetics consistent with established radiati on - thermal degradation models. ACKNOWLEDGEMENTS We gratefully acknowledge ongoing technical support at the LICA facility and extensive sample handling provided by Maryla Wasiolek and Don Hans on. Sam Durbin and Patrick Mattie are recognized for valuable guidance throughout the year and assistance in the preparation of the final report. Doug Brunson is appreciated for sample analysis, compilation and plotting of experimental data.« less

Unprecedented quality factors at accelerating gradients up to 45 MVm-1 in niobium superconducting resonators via low temperature nitrogen infusion

NASA Astrophysics Data System (ADS)

Grassellino, A.; Romanenko, A.; Trenikhina, Y.; Checchin, M.; Martinello, M.; Melnychuk, O. S.; Chandrasekaran, S.; Sergatskov, D. A.; Posen, S.; Crawford, A. C.; Aderhold, S.; Bice, D.

2017-09-01

We report the finding of new surface treatments that permits one to manipulate the niobium resonator nitrogen content in the first few nanometers in a controlled way, and the resonator fundamental Mattis-Bardeen surface resistance and residual resistance accordingly. In particular, we find surface ‘infusion’ conditions that systematically (a) increase the quality factor of these 1.3 GHz superconducting radio frequency (SRF) bulk niobium resonators, up to very high gradients; (b) increase the achievable accelerating gradient of the cavity compared to its own baseline with state-of-the-art surface processing. Cavities subject to the new surface process have more than two times the state-of-the-art Q at 2 K for accelerating fields >35 MVm-1. Moreover, very high accelerating gradients ˜45 MVm-1 are repeatedly reached, which correspond to peak magnetic surface fields of 190 mT, among the highest measured for bulk niobium cavities. These findings open the opportunity to tailor the surface impurity content distribution to maximize performance in Q and gradients, and have therefore very important implications on future performance and cost of SRF based accelerators. They also help deepen the understanding of the physics of the RF niobium cavity surface.

Quantum Spin Liquids and Fractionalization

NASA Astrophysics Data System (ADS)

Misguich, Grégoire

This chapter discusses quantum antiferromagnets which do not break any symmetries at zero temperature - also called "spin liquids" - and focuses on lattice spin models with Heisenberg-like (i.e. SU(2)-symmetric) interactions in dimensions larger than one. We begin by discussing the Lieb-Schultz-Mattis theorem and its recent extension to D > 1 by Hastings (2004), which establishes an important distinction between spin liquids with an integer and with a half-integer spin per unit cell. Spin liquids of the first kind, "band insulators", can often be understood by elementary means, whereas the latter, "Mott insulators", are more complex (featuring "topological order") and support spin-1/2 excitations (spinons). The fermionic formalism (Affleck and Marston, 1988) is described and the effect of fluctuations about mean-field solutions, such as the possible creation of instabilities, is discussed in a qualitative way. In particular, we explain the emergence of gauge modes and their relation to fractionalization. The concept of the projective symmetry group (X.-G. Wen, 2002) is introduced, with the aid of some examples. Finally, we present the phenomenology of (gapped) short-ranged resonating-valence-bond spin liquids, and make contact with the fermionic approach by discussing their description in terms of a fluctuating Z 2 gauge field. Some recent references are given to other types of spin liquid, including gapless ones.

Cognitive decline and survival in Alzheimer's disease according to education level.

PubMed

Bruandet, A; Richard, F; Bombois, S; Maurage, C A; Masse, I; Amouyel, P; Pasquier, F

2008-01-01

We tested the hypothesis that a higher education level is associated with faster cognitive decline and lower survival in a cohort of 670 Alzheimer's disease patients, followed for 3.5 years at the Lille-Bailleul memory centre. The patients were categorized in 3 groups according to educational levels: low (12 years). Cognitive function was measured with the Mini Mental State Examination (MMSE) and the Mattis Dementia Rating Scale (DRS). Survival was analyzed with a Cox model. Analyses were adjusted for age, sex, cholinesterase inhibitor treatment, diabetes, hypertension, visible vascular lesions on MRI, baseline DRS and MMSE. The adjusted mixed random model showed that MMSE declined faster for patients with high and intermediate educational levels compared with those with a low educational level (p < 0.0001). The mean annually adjusted DRS decline was highest for the groups with the most education (p = 0.05). The mortality risk was not higher in the better-educated groups (high vs. low: RR = 0.84; 95% CI = 0.35-1.99, intermediate vs. low: RR = 0.82; 95% CI = 0.41-1.63). In our cohort, highly educated patients had a faster cognitive decline than less educated patients but similar mortality rates. Our findings support the cognitive reserve hypothesis. (c) 2007 S. Karger AG, Basel.

New SSMS Techniques for the Determination of Rhodium and Other Platinum- Group Elements in Carbonaceous Chondrites

NASA Astrophysics Data System (ADS)

Jochum, K. P.; Seufert, H. M.

1995-09-01

We have developed new spark source mass spectrometric (SSMS) techniques for simultaneous analysis of platinum-group elements (PGE) together with other trace elements in stony meteorites. We have measured elemental abundances of Rh, Ru, Os, Ir, Pt, Au in carbonaceous chondrites of different types including the two CI chondrites Orgueil and Ivuna. These data are relevant for the determination of solar-system abundances. Whereas the solar-system abundances of most PGE are well known, this is not the case for Rh, and no literature data exist for carbonaceous chondrites, mainly because of analytical difficulties. The SSMS techniques include new calibration procedures and the use of a recently developed multi-ion counting (MIC) system [1]. The mono-isotopic element Rh and the other PGE were determined by using internal standard elements (e.g., Nd, U) that were measured by isotope dilution in the same sample electrode material. The data were calibrated with certified standard solutions of PGE which were doped on trace-element poor rock samples. Ion abundances were measured using both the conventional photoplate detection and the ion-counting techniques. The new MIC technique that uses up to 20 small channeltrons for ion counting measurements has the advantage of improved precision, detection limits and analysis time compared to photoplate detection. Tab. 1 shows the Rh analyses for the meteorites Orgueil, Ivuna, Murchison, Allende and Karoonda obtained by conventional photoplate detection. These are the first Rh results for carbonaceous chondrites. The data for the two CI chondrites Orgueil and Ivuna are identical and agree within 4 % with the CI estimate of Anders and Grevesse [2] which was derived indirectly from analyses for H-chondrites. The PGE Os, Ir, Pt, Au and W, Re, Th, U concentrations were determined by both detection systems. Data obtained with the MIC system are more precise (about 4% for concentrations in the ppb range) compared to the photoplate detection system (about 10 - 15 %). Both data sets agree within error limits. Rhodium correlates well with Pt and other PGE indicating no significant fractionation between the different types of carbonaceous chondrites (Tab. 1). References: [1] Jochum K. P. et al. (1994) Fresenius J. Anal. Chem., 350, 642-644. [2] Anders E. and Grevesse N. (1989) GCA, 53, 197-214.

Saturn Apollo Program

NASA Image and Video Library

1969-07-16

From the right, NASA administrator, Dr. Thomas O. Paine talks with U.S. Vice President Spiro T. Agnew while awaiting the launch of Saturn V (AS-506) that carried the Apollo 11 spacecraft to the Moon for man’s historic first landing on the lunar surface. At center is astronaut William Anders, a member of the first crew to orbit the moon during the Apollo 8 mission. At left is Lee B. James, director of Program Management at the NASA Marshall Space Flight Center (MSFC) where the Saturn V was developed. The craft lifted off from launch pad 39 at Kennedy Space Flight Center (KSC) on July 16, 1969. The moon bound crew included astronauts Neil A. Armstrong, commander; Michael Collins, Command Module (CM) pilot; and Edwin E. Aldrin Jr., Lunar Module (M) pilot. The mission finalized with splashdown in the Pacific Ocean on July 24, 1969. With the success of Apollo 11, the national objective to land men on the Moon and return them safely to Earth had been accomplished.

Next Generation Extended Lagrangian Quantum-based Molecular Dynamics

NASA Astrophysics Data System (ADS)

Negre, Christian

2017-06-01

A new framework for extended Lagrangian first-principles molecular dynamics simulations is presented, which overcomes shortcomings of regular, direct Born-Oppenheimer molecular dynamics, while maintaining important advantages of the unified extended Lagrangian formulation of density functional theory pioneered by Car and Parrinello three decades ago. The new framework allows, for the first time, energy conserving, linear-scaling Born-Oppenheimer molecular dynamics simulations, which is necessary to study larger and more realistic systems over longer simulation times than previously possible. Expensive, self-consinstent-field optimizations are avoided and normal integration time steps of regular, direct Born-Oppenheimer molecular dynamics can be used. Linear scaling electronic structure theory is presented using a graph-based approach that is ideal for parallel calculations on hybrid computer platforms. For the first time, quantum based Born-Oppenheimer molecular dynamics simulation is becoming a practically feasible approach in simulations of +100,000 atoms-representing a competitive alternative to classical polarizable force field methods. In collaboration with: Anders Niklasson, Los Alamos National Laboratory.

Dignitaries Await Apollo 11 Lift Off

NASA Technical Reports Server (NTRS)

1969-01-01

From the right, NASA administrator, Dr. Thomas O. Paine talks with U.S. Vice President Spiro T. Agnew while awaiting the launch of Saturn V (AS-506) that carried the Apollo 11 spacecraft to the Moon for man's historic first landing on the lunar surface. At center is astronaut William Anders, a member of the first crew to orbit the moon during the Apollo 8 mission. At left is Lee B. James, director of Program Management at the NASA Marshall Space Flight Center (MSFC) where the Saturn V was developed. The craft lifted off from launch pad 39 at Kennedy Space Flight Center (KSC) on July 16, 1969. The moon bound crew included astronauts Neil A. Armstrong, commander; Michael Collins, Command Module (CM) pilot; and Edwin E. Aldrin Jr., Lunar Module (M) pilot. The mission finalized with splashdown in the Pacific Ocean on July 24, 1969. With the success of Apollo 11, the national objective to land men on the Moon and return them safely to Earth had been accomplished.

Increased Incidence Rate of Trauma- and Stressor-related Disorders in Denmark After the Breivik Attacks in Norway.

PubMed

Hansen, Bertel T; Dinesen, Peter T; Østergaard, Søren D

2017-11-01

On 22 July 2011, Anders Breivik killed 77 adults and children in Norway. Having recently documented increases in the incidence of trauma- and stressor-related disorders in Denmark after the 9/11 attacks, we hypothesized that the Breivik attacks-due to their geographic proximity-would be followed by even larger increases in Denmark. Using population-based data from the Danish Psychiatric Central Research Register (1995-2012), we conducted an intervention analysis of the change in the incidence of trauma- and stressor-related disorders after the Breivik attacks. The incidence rate increased by 16% over the following 1½ years after the Breivik attacks, corresponding to 2736 additional cases. In comparison, 9/11 was followed by a 4% increase. We also present evidence of a subsequent surge in incidence stimulated by media attention. This study bolsters previous findings on extra-national consequences of terrorism and indicates that geographic proximity and media coverage may exacerbate effects.

Spin fluctations and heavy fermions in the Kondo lattice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khaliullin, G.G.

1994-09-01

This paper studies the spectrum of the spin and electronic excitations of the Kondo lattice at low temperatures. To avoid unphysical states, the Mattis {open_quotes}drone{close_quotes}-fermion representation for localized spins is employed. First, the known Fermi liquid properties of a single impurity are examined. The behavior of the correlator between a localized spin and the electron spin density at large distances shows that the effective interaction between electrons on the Fermi level and low-energy localized spin fluctuations scales as {rho}{sup {minus}1}, where {rho} is the band-state density. This fact is developed into a renormalization of the band spectrum in a periodicmore » lattice. If the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between localized spins is much smaller than the Kondo fluctuation frequency {omega}{sub k}, the temperature of the crossover to the single-parameter Fermi liquid mode is determined by {omega}{sub k}. When the RKKY interaction becomes of order {omega}{sub k}, there is a new scale {omega}{sub sf}, the energy of the (antiferromagnetic) paramagnon mode, with {omega}{sub sf}{much_lt}{omega}{sub k}. Here the coherent Fermi liquid regime is realized only below a temperature T{sub coh} of order {omega}{sub sf}, while above T{sub coh} quasiparticle damping exhibits a linear temperature dependence. Finally, the nuclear-spin relaxation rate is calculated. 42 refs.« less

The isotopic composition of ore lead of the Creede mining district and vicinity, San Juan Mountains, Colorado: Text of a talk presented at the San Juan Mountains symposium to honor Thomas A. Steven; Rocky Mountain Section meeting of the Geological Society of America, May 2, 1987, Boulder, Colorado

USGS Publications Warehouse

Foley, N.K.; Barton, P.B.; Bethke, P.M.; Doe, B.R.

1988-01-01

Recent work allows us to extend the results of Doe et al. and to consider alternative processes to explain the widespread homogeneity and radiogenic nature of the ore lead: 1) David Matty (pers. commun., 1986) has shown that some minor volcanic units in the area have unusually radiogneic lead values; magmas comparable in composition to the units are a possible, though improbable, source of the ore lead. 2) The uniformity of the isotopic values of galenas may have resulted from homogenization during an extensive potassium-metasomatic event that predated the ores; this possibility is being tested in an on-going study of feldspars from metasomatized and unmetasomatized rocks. 3) Recent regional studies suggest the possibility of a prevolcanic, NNW-trending graben system filled by clastic sediments derived from the Precambrian basement, a process that would have an homogenizing effect on the lead isotopes. This interpretation implies importation, deep within the Creede hydrologic system, of fluids from remote sources. These alternatives show that the Pbisotope systematics may have a profound impact on the interpretation of the Creede hydrothermal system, and that further study is warranted.

Executive functions in mild cognitive impairment: emergence and breakdown of neural plasticity.

PubMed

Clément, Francis; Gauthier, Serge; Belleville, Sylvie

2013-05-01

Our goal was to test the effect of disease severity on the brain activation associated with two executive processes: manipulation and divided attention. This was achieved by administrating a manipulation task and a divided attention task using functional magnetic resonance imaging to 24 individuals with mild cognitive impairment (MCI) and 14 healthy controls matched for age, sex and education. The Mattis Dementia Rating Scale was used to divide persons with MCI into those with better and worse cognitive performances. Both tasks were associated with more brain activation in the MCI group with higher cognition than in healthy controls, particularly in the left frontal areas. Correlational analyses indicated that greater activation in a frontostriatal network hyperactivated by the higher-cognition group was related with better task performance, suggesting that these activations may support functional reorganization of a compensatory nature. By contrast, the lower-cognition group failed to show greater cerebral hyperactivation than controls during the divided attention task and, during the manipulation task, and showed less brain activation than controls in the left ventrolateral cortex, a region commonly hypoactivated in patients with Alzheimer's disease. These findings indicate that, during the early phase of MCI, executive functioning benefits from neural reorganization, but that a breakdown of this brain plasticity characterizes the late stages of MCI. Copyright © 2012 Elsevier Ltd. All rights reserved.

The effect of cognitive impairment on mental healthcare costs for individuals with severe psychiatric illness.

PubMed

Mackin, R Scott; Delucchi, Kevin L; Bennett, Robert W; Areán, Patricia A

2011-02-01

This study was conducted to determine the effect of cognitive impairment (CI) on mental healthcare costs for older low-income adults with severe psychiatric illness. Data were collected from 62 ethnically diverse low-income older adults with severe psychiatric illness who were participating in day programming at a large community mental health center. CI was diagnosed by a neuropsychologist utilizing the Mattis Dementia Rating Scale-Second Edition and structured ratings of functional impairment (Clinical Dementia Rating Scale). Mental healthcare costs for 6, 12, and 24-month intervals before cognitive assessments were obtained for each participant. Substance abuse history was evaluated utilizing a structured questionnaire, depression symptom severity was assessed utilizing the Hamilton Depression Rating Scale, and psychiatric diagnoses were obtained through medical chart abstraction. CI was exhibited by 61% of participants and was associated with significantly increased mental healthcare costs during 6, 12, and 24-month intervals. Results of a regression analysis indicated that ethnicity and CI were both significant predictors of log transformed mental healthcare costs over 24 months with CI accounting for 13% of the variance in cost data. CI is a significant factor associated with increased mental healthcare costs in patients with severe psychiatric illness. Identifying targeted interventions to accommodate CI may lead to improving treatment outcomes and reducing the burden of mental healthcare costs for individuals with severe psychiatric illness.

Prospective evaluation of behavioral scales in the behavioral variant of frontotemporal dementia.

PubMed

Boutoleau-Bretonnière, Claire; Lebouvier, Thibaud; Volteau, Christelle; Jaulin, Philippe; Lacomblez, Lucette; Damier, Philippe; Thomas-Anterion, Catherine; Vercelletto, Martine

2012-01-01

The Neuropsychiatric Inventory (NPI) and the Frontal Behavioral Inventory (FBI) are widely used in patients with the behavioral variant of frontotemporal dementia (bvFTD). Yet, few data are available on the long-term relevance of these scales. Based on a bvFTD population that participated in the Memantine Clinical Trial (NCT00200538), we studied the evolution and correlation between scores obtained on behavioral scales (NPI and FBI), cognitive scales [Mini-Mental State Examination (MMSE) and Mattis Dementia Rating Scale (MDRS)] and a burden scale [Zarit Burden Inventory (ZBI)]. The assessments were performed at 1 year in 41 patients and at 2 years in 23 patients who agreed to participate in this open-label study. The 2-year scores obtained on the FBI were significantly higher than the scores at inclusion while those obtained on the NPI did not change. There were significant correlations between the FBI, and the MDRS and MMSE, especially regarding the negative items. The ZBI correlated with behavioral scales at all stages for positive items. This study based on a large population shows that the FBI is a better tool than the NPI for the long-term assessment of bvFTD patients. Moreover, the FBI allows a distinction to be made between behavioral disturbances that involve cognitive functions from those which have an important impact on caregiver burden. Copyright © 2012 S. Karger AG, Basel.

metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis.

PubMed

Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

2016-07-01

A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness.Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Code is available at https://github.com/aalto-ics-kepaco anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis

PubMed Central

Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J.; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T.; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

2016-01-01

Motivation: A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. Results: We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness. Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Availability and implementation: Code is available at https://github.com/aalto-ics-kepaco Contacts: anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27153689

Temperature dependence of the superconducting energy gaps in Ca9.35La0.65(Pt3As8)(Fe2As2)5 single crystal.

PubMed

Seo, Yu-Il; Choi, Woo-Jae; Ahmad, D; Kimura, Shin-Ichi; Kwon, Yong Seung

2018-06-05

We measured the optical reflectivity R(ω) for an underdoped (Ca 0.935 La 0.065 ) 10 (Pt 3 As 8 )(Fe 2 As 2 ) 5 single crystal and obtained the optical conductivity [Formula: see text] using the K-K transformation. The normal state [Formula: see text] at 30 K is well fitted by a Drude-Lorentz model with two Drude components (ω p1  = 1446 cm -1 and ω p2  = 6322 cm -1 ) and seven Lorentz components. Relative reflectometry was used to accurately determine the temperature dependence of the superconducting gap at various temperatures below T c . The results clearly show the opening of a superconducting gap with a weaker second gap structure; the magnitudes for the gaps are estimated from the generalized Mattis-Bardeen model to be Δ 1  = 30 and Δ 2  = 50 cm -1 , respectively, at T = 8 K, which both decrease with increasing temperature. The temperature dependence of the gaps was not consistent with one-band BCS theory but was well described by a two-band (hence, two gap) BCS model with interband interactions. The temperature dependence of the superfluid density is flat at low temperatures, indicating an s-wave full-gap superconducting state.

Some physical approaches to protein folding

NASA Astrophysics Data System (ADS)

Bascle, J.; Garel, T.; Orland, H.

1993-02-01

To understand how a protein folds is a problem which has important biological implications. In this article, we would like to present a physics-oriented point of view, which is twofold. First of all, we introduce simple statistical mechanics models which display, in the thermodynamic limit, folding and related transitions. These models can be divided into (i) crude spin glass-like models (with their Mattis analogs), where one may look for possible correlations between the chain self-interactions and the folded structure, (ii) glass-like models, where one emphasizes the geometrical competition between one- or two-dimensional local order (mimicking α helix or β sheet structures), and the requirement of global compactness. Both models are too simple to predict the spatial organization of a realistic protein, but are useful for the physicist and should have some feedback in other glassy systems (glasses, collapsed polymers .... ). These remarks lead us to the second physical approach, namely a new Monte-Carlo method, where one grows the protein atom-by-atom (or residue-by-residue), using a standard form (CHARMM .... ) for the total energy. A detailed comparison with other Monte-Carlo schemes, or Molecular Dynamics calculations, is then possible; we will sketch such a comparison for poly-alanines. Our twofold approach illustrates some of the difficulties one encounters in the protein folding problem, in particular those associated with the existence of a large number of metastable states. Le repliement des protéines est un problème qui a de nombreuses implications biologiques. Dans cet article, nous présentons, de deux façons différentes, un point de vue de physicien. Nous introduisons tout d'abord des modèles simples de mécanique statistique qui exhibent, à la limite thermodynamique, des transitions de repliement. Ces modèles peuvent être divisés en (i) verres de spin (éventuellement à la Mattis), où l'on peut chercher des corrélations entre les interactions intrachaîne et la structure repliée, (ii) verres, où l'on met l'accent sur la compétition géométrique entre l'ordre local uni- ou bi-dimensionnel (qui modèle les structures en hélices α ou en feuillets β), et la contrainte globale de compacité. Ces deux types de modèles sont trop simples pour l'étude de vraies protéines, mais ils devraient s'appliquer dans le domaine de la transition vitreuse, des polymères collapsés,... La deuxième voie d'étude est une méthode Monte-Carlo, où on fait croître la protéine atome par atome (ou résidu par résidu), à l'aide d'une forme donnée de l'énergie totale de la protéine (CHARMM, ... ). Cette méthode peut être alors comparée aux autres méthodes numériques; nous comparons ainsi nos résultats avec des calculs de dynamique moléculaire pour le cas des poly-alanines. Cette double approche est une bonne illustration des difficultés que l'on rencontre dans le problème du repliement des protéines (nombreux états métastables, ... ).

Black Carbon in Sedimentary Organic Carbon in the Northeast Pacific using the Benzene Polycarboxylic Acid Method

NASA Astrophysics Data System (ADS)

Coppola, A. I.; Ziolkowski, L. A.; Druffel, E. R.

2010-12-01

Black carbon (BC) in the Northeast Pacific ultrafiltered dissolved organic matter (UDOM) was found to be surprisingly old with a 14C age of 18,000 +/-3,000 14C years (Ziolkowski and Druffel, 2010) using the Benzene Polycarboxylic Acid (BPCA) method, while BC in sedimentary organic carbon (SOC) was found to be 2,400-12,900 14C years older than non-BC SOC (Masiello and Druffel, 1998) with a different method. Using the dichromate-sulfuric acid oxidation method (Wolbach and Anders, 1989), Masiello and Druffel (1998) estimated that 12-31% of SOC in the Northeast Pacific and the Southern Ocean surface sediments was black carbon (BC). However, the dichromate-sulfuric acid oxidation may over-estimate the concentration of BC, because this method is more biased toward modern (char) material (Currie et al., 2002). Alternatively, the BPCA method isolates aromatic components of BC as benzene rings substituted with carboxylic acid groups, and provides structural information about the BC. Recent modifications to the BPCA method by Ziolkowski and Druffel (2009) involve few biases in quantifying BC in the continuum between char and soot in UDOM. Here we use the BPCA method to determine the concentrations and 14C values of BC in sediments from three sites in the Northeast Pacific Ocean. Constraining the difference between non-BC SOC and BC-SOC using the BPCA method allows for a more precise estimate of how much BC is present in the sediments and its 14C age. Presumably, the intermediate reservoir of BC is oceanic dissolved organic carbon (DOC) and is, in part, responsible for DOC’s great 14C age. These results can be utilized to better constrain the oceanic carbon budget as a possible sink of BC. References: Currie, L. A., Benner Jr., B. A., Kessler, J.D., et al (2002), A critical evaluation of interlaboratory data on total, elemental, and isotopic carbon in the carbonaceous particle reference material, nist srm 1649a, J. Res. Natl. Inst. Stand. Technol., 107, 279-298. Masiello, C., and E. R. Druffel (1988), Black carbon in deep-sea sediments, Science, 280, 1911-1913. Wolbach, W., and E. Anders (1989), Elemental carbon in sediments: Determination and isotopic analysis in presence of kerogen, Geochim. Cosmochim. Acta, 53, 1637-1647. Ziolkowski, L. A., and E. R. Druffel (2010), Aged black carbon identified in marine dissolved organic carbon, J. Geophys. Res., 37, L16601, doi: 10.1029/2010GL043963.

Effects of Insulin and Octreotide on Memory and Growth Hormone in Alzheimer's Disease

PubMed Central

Watson, G. Stennis; Baker, Laura D.; Cholerton, Brenna A.; Rhoads, Kristoffer W.; Merriam, George R.; Schellenberg, Gerard D.; Asthana, PhD;Sanjay; Cherrier, Monique; Craft, Suzanne

2009-01-01

Both insulin alone and the somatostatin analogue octreotide alone facilitate memory in patients with Alzheimer's disease (AD). Since octreotide inhibits endogenous insulin secretion, the cognitive effects of insulin and octreotide may not be independent. This study tested the individual and interactive effects of insulin and octreotide on memory and plasma growth hormone (GH) levels in older adults. Participants were 16 memory-impaired (AD=7, amnestic mild cognitive impairment=9; apolipoprotein E [APOE] ε4- [no ε4 alleles]=9, ε4+ [1-2 ε4 alleles]=7) and 19 cognitively-intact older adults (APOE ε4-=17, ε4+=1). On separate days, fasting participants received counterbalanced infusions of (1) insulin (1 mU·kg-1·min-1) and dextrose to maintain euglycemia, (2) octreotide (150 μg/h), (3) insulin, dextrose, and octreotide, or (4) saline. Story recall was the principal endpoint. Insulin alone facilitated delayed recall for ε4-patients, relative to ε4+ patients (P=0.0012). Furthermore, ε4- patients with higher Mattis Dementia Rating Scale (DRS) scores had greater octreotide-induced memory facilitation (P=0.0298). For healthy adults, octreotide facilitated memory (P=0.0122). Unexpectedly, hyperinsulinemia with euglycemia increased GH levels in healthy controls (P=0.0299). Thus, insulin and octreotide appear to regulate memory in older adults. APOE ε4 genotype modulates responses to insulin and octreotide. Finally, insulin may regulate GH levels during euglycemia. PMID:19625744

Benton Judgment of Line Orientation (JoLO) Test: A Brief and Useful Measure for Assessing Visuospatial Abilities in Manifest, but not Premanifest, Huntington's Disease.

PubMed

Corey-Bloom, Jody; Gluhm, Shea; Herndon, Andrew; Haque, Ameera S; Park, Sungmee; Gilbert, Paul E

2016-01-01

Visuospatial deficits have been described in Huntington's disease (HD); however, the extent of these deficits remains unclear. The Benton Judgment of Line Orientation (JoLO) Test, commonly used to assess visuospatial ability, requires minimal motor involvement. It has demonstrated sensitivity to visuospatial deficits in Parkinson's disease; however, few studies have examined performance on this test in HD. The objective of the current study was to assess visuospatial ability in premanifest and manifest HD using the JoLO. A global cognitive measure, the Mattis Dementia Rating Scale (DRS), was used to stratify manifest HD patients as mild (DRS ≥129) vs. moderate-severe (DRS ≤128). Fifty mild, 42 moderate-severe, and 30 premanifest HD subjects, as well as 35 matched controls, were administered the JoLO. HD Burden of Pathology (BOP) scores were used as a measure of disease severity. Results revealed that the total manifest HD sample (p <  0.001), in addition to the mild (p = 0.028), and moderate-severe (p <  0.001), but not premanifest, HD subjects scored significantly lower on the JoLO compared to normal controls. Our results suggest that the JoLO is useful for detecting visuospatial deficits across various stages of manifest HD. However, any visuospatial impairment that might be present during the premanifest stage of HD was not detected using the JoLO in the present sample.

Is ApoE ε4 Associated with Cognitive Functioning in African Americans Diagnosed with Alzheimer Disease? An Exploratory Study

PubMed Central

Mount, David L.; Ashley, Angela V.; Lah, James J.; Levey, Allan I.; Goldstein, Felicia C.

2015-01-01

Objective The effect of the apolipoprotein ε4 allele (ApoE ε4) on cognitive performance in patients with probable Alzheimer disease (AD) has been studied in primarily Caucasian samples. The aim of this exploratory study was to examine whether the presence of ApoE ε4 is associated with cognitive performance in African American AD patients. Methods A cross-sectional, retrospective design was used to address the study objective. Data were extracted from the records of 65 African American patients who participated in the National Institutes of Health-National Institute on Aging (NIH-NIA) Emory University Alzheimer Disease Center Registry. Inclusion criteria were a clinical diagnosis of probable AD, cognitive testing using the Mattis Dementia Rating Scale and the Consortium to Establish a Registry for Alzheimer Disease (CERAD) neuropsychological battery, and ApoE genotyping. Results Seventy percent of the patients were ApoE ε4 positive. Multiple regression analyses indicated that ApoE ε4 was significantly associated with poorer design copying (CERAD Constructional Praxis subtest), but other significant relationships were not observed between positive ε4 status and cognitive performance. Conclusions These preliminary findings suggest that the ApoE ε4 allele is not strongly associated with a particular pattern of cognitive functioning in African Americans once they are diagnosed with AD. However, these findings require replication in a large prospectively recruited and population-based sample of African American AD patients before firm conclusions can be reached. PMID:19668025

Therapeutic application of melatonin in mild cognitive impairment

PubMed Central

Cardinali, Daniel P; Vigo, Daniel E; Olivar, Natividad; Vidal, María F; Furio, Analía M; Brusco, Luis I

2012-01-01

Mild cognitive impairment (MCI) is an etiologically heterogeneous syndrome defined by cognitive impairment in advance of dementia. We previously reported in a retrospective analysis that daily 3 - 9 mg of a fast-release melatonin preparation given p. o. at bedtime for up to 3 years significantly improved cognitive and emotional performance and daily sleep/wake cycle in MCI patients. In a follow up of that study we now report data from another series of 96 MCI outpatients, 61 of who had received daily 3 - 24 mg of a fast-release melatonin preparation p. o. at bedtime for 15 to 60 months. Melatonin was given in addition to the standard medication prescribed by the attending psychiatrist. Patients treated with melatonin exhibited significantly better performance in Mini–Mental State Examination and the cognitive subscale of the Alzheimer’s disease Assessment Scale. After application of a neuropsychological battery comprising a Mattis´ test, Digit-symbol test, Trail A and B tasks and the Rey´s verbal test, better performance was found in melatonin-treated patients for every parameter tested. Abnormally high Beck Depression Inventory scores decreased in melatonin-treated patients, concomitantly with the improvement in the quality of sleep and wakefulness. The comparison of the medication profile in both groups of MCI patients indicated that 9.8% in the melatonin group received benzodiazepines vs. 62.8% in the non-melatonin group. The results further support that melatonin can be a useful add-on drug for treating MCI in a clinic environment. PMID:23383398

Impaired executive function can predict recurrent falls in Parkinson's disease.

PubMed

Mak, Margaret K; Wong, Adrian; Pang, Marco Y

2014-12-01

To examine whether impairment in executive function independently predicts recurrent falls in people with Parkinson's disease (PD). Prospective cohort study. University motor control research laboratory. A convenience sample of community-dwelling people with PD (N=144) was recruited from a patient self-help group and movement disorders clinics. Not applicable. Executive function was assessed with the Mattis Dementia Rating Scale Initiation/Perseveration (MDRS-IP) subtest, and fear of falling (FoF) with the Activities-specific Balance Confidence (ABC) Scale. All participants were followed up for 12 months to record the number of monthly fall events. Forty-two people with PD had at least 2 falls during the follow-up period and were classified as recurrent fallers. After accounting for demographic variables and fall history (P=.001), multiple logistic regression analysis showed that the ABC scores (P=.014) and MDRS-IP scores (P=.006) were significantly associated with future recurrent falls among people with PD. The overall accuracy of the prediction was 85.9%. With the use of the significant predictors identified in multiple logistic regression analysis, a prediction model determined by the logistic function was generated: Z = 1.544 + .378 (fall history) - .045 (ABC) - .145 (MDRS-IP). Impaired executive function is a significant predictor of future recurrent falls in people with PD. Participants with executive dysfunction and greater FoF at baseline had a significantly greater risk of sustaining a recurrent fall within the subsequent 12 months. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Helium diffusion in the sun

NASA Technical Reports Server (NTRS)

Bahcall, J. N.; Pinsonneault, M. H.

1992-01-01

We calculate improved standard solar models using the new Livermore (OPAL) opacity tables, an accurate (exportable) nuclear energy generation routine which takes account of recent measurements and analyses, and the recent Anders-Grevesse determination of heavy element abundances. We also evaluate directly the effect of the diffusion of helium with respect to hydrogen on the calculated neutrino fluxes, on the primordial solar helium abundance, and on the depth of the convective zone. Helium diffusion increases the predicted event rates by about 0.8 SNU, or 11 percent of the total rate, in the chlorine solar neutrino experiment, by about 3.5 SNU, or 3 percent, in the gallium solar neutrino experiments, and by about 12 percent in the Kamiokande and SNO solar neutrino experiments. The best standard solar model including helium diffusion and the most accurate nuclear parameters, element abundances, and radiative opacity predicts a value of 8.0 SNU +/- 3.0 SNU for the C1-37 experiment and 132 +21/-17 SNU for the Ga - 71 experiment, where the uncertainties include 3 sigma errors for all measured input parameters.

Fires at the K/T boundary - Carbon at the Sumbar, Turkmenia, site

NASA Technical Reports Server (NTRS)

Wolbach, Wendy S.; Anders, Edward; Nazarov, Michael A.

1990-01-01

Results are reported on carbon analysis and on C and Ir correlations in samples from the marine K-T boundary site SM-4 at the Sumbar River in Turkmenia (USSR), which has the largest known Ir anomaly (580 ng/cq cm). In addition, the boundary clay is thick, and is undisturbed by bioturbation. Kerogen and delta-C-13 elemental carbon in the boundary clay were resolved using a Cr2O7(2-) oxidation method of Wolbach and Anders (1989). It was found that Ir and shocked quartz, both representing impact ejecta, rise sharply at the boundary, peak in the basal layer, and then decline. On the other hand, soot and total elemental C show a similar spike in the basal layer but then rise rather than fall, peking at 7 cm. Results indicate that fires at the SM-4 K-T boundary site started before the basal layer had settled, implying that ignition and spreading of major fires became possible at the time of or very soon after the meteorite impact.

Cell and tissue culture of Miscanthus Sacchariflorus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Godovikova, V.A.; Moiseyeva, E.A.; Shumny, V.K.

1995-11-01

Since recent time search and introduction of new species of plants have paid attention. More perspective are perennial low maintenance landscape plants from genera Phragmites L. and Miscanthus Anderss. known as high speed growing and great amount of cellulose`s containing. Absence of seeds production and limited distribution area prevent from immediately introduction the plants of this species. The main goal of our investigation is the scientific development of the cell and tissue culture methods to get changing clones, salt and cold tolerant plants and their micropogation. At present there are collection of biovariety represented by subspecies, ecotypes and plant regenerantsmore » of two species - Miscanthus purpurascens (Anders.) and Miscanthus sacchariflorus (Maxim.). Successful results have been achieved in screening of culture media, prepared on MS base medium and contained a row of tropic components to protect the explant and callus tissue from oxidation and necrosis. Initially the callus was induced from stem segments, apical and nodular meristem of vegetative shoots of elulalia, growing in hydroponic greenhouse. Morphological and cytologic analysis of plant-regenerants have been done.« less

Niobium and tantalum: indispensable twins

USGS Publications Warehouse

Schulz, Klaus; Papp, John

2014-01-01

Niobium and tantalum are transition metals almost always paired together in nature. These “twins” are difficult to separate because of their shared physical and chemical properties. In 1801, English chemist Charles Hatchett uncovered an unknown element in a mineral sample of columbite; John Winthrop found the sample in a Massachusetts mine and sent it to the British Museum in London in 1734. The name columbium, which Hatchet named the new element, came from the poetic name for North America—Columbia—and was used interchangeably for niobium until 1949, when the name niobium became official. Swedish scientist Anders Ekberg discovered tantalum in 1802, but it was confused with niobium, because of their twinned properties, until 1864, when it was recognized as a separate element. Niobium is a lustrous, gray, ductile metal with a high melting point, relatively low density, and superconductor properties. Tantalum is a dark blue-gray, dense, ductile, very hard, and easily fabricated metal. It is highly conductive to heat and electricity and renowned for its resistance to acidic corrosion. These special properties determine their primary uses and make niobium and tantalum indispensable.

Effects of lesions to the left lateral prefrontal cortex on task-specific top-down biases and response strategies in blocked-cyclic naming.

PubMed

Belke, Eva

Anders, Riès, van Maanen and Alario put forward evidence accumulation modelling of object naming times as an alternative to neural network models of lexical retrieval. The authors exemplify their approach using data from the blocked-cyclic naming paradigm, requiring speakers to repeatedly name small sets of related or unrelated objects. The effects observed with this paradigm are understood reasonably well within the tradition of neural network modelling. However, implemented neural network models do not specify interfaces for task-specific top-down influences and response strategies that are likely to play a role in the blocked-cyclic naming paradigm, distinguishing it from continuous, non-cyclic manipulations of the naming context. I argue that the evidence accumulation approach falls short on this account as well, as it does not specify the potential contribution of task-specific top-down processes and strategic facilitation effects to the response time distributions. Future endeavours to model or fit data from blocked-cyclic naming experiments should strive to do so by simultaneously considering data from continuous context manipulations.

[Summary of the practice guideline for the diagnosis and treatment of ADHD in adolescents and adults with addictions].

PubMed

Matthys, Frieda; Joostens, Peter; van den Brink, Wim; Sabbe, Bernard

2013-01-01

Various guidelines are available for the diagnosis and treatment of ADHD in adults, but not for patients with ADHD and a comorbid substance use disorder (SUD). In 2010, the Addiction Medicine Working Party, a division of the VAD (Verenigingvoor Alcohol- en andere Drugproblemen/Association for Alcohol and other Drug Problems) developed a practice guideline on how, when and by whom ADHD can be diagnosed in patients with an addiction, and how these patients should be treated. Given the high prevalence of ADHD in treatment-seeking SUD patients and the availability of valid screening instruments, all SUD patients should be screened for ADHD as soon as their drug use has stabilized. Acquiring information from external sources as well as clinical observation and questionnaires are important tools for the establishment of the diagnosis of ADHD. Integrated treatment primarily includes psycho-education, coaching and cognitive behavioural therapy in addition to pharmacotherapy. Evidence-based treatments for addiction may also be effective in patients with concomitant ADHD, provided the methods are adapted to the limitations that are associated with this condition.

Twisting Anderson pseudospins with light: Quench dynamics in terahertz-pumped BCS superconductors

NASA Astrophysics Data System (ADS)

Chou, Yang-Zhi; Liao, Yunxiang; Foster, Matthew S.

2017-03-01

We study the preparation (pump) and the detection (probe) of far-from-equilibrium BCS superconductor dynamics in THz pump-probe experiments. In a recent experiment [R. Matsunaga, Y. I. Hamada, K. Makise, Y. Uzawa, H. Terai, Z. Wang, and R. Shimano, Phys. Rev. Lett. 111, 057002 (2013), 10.1103/PhysRevLett.111.057002], an intense monocycle THz pulse with center frequency ω ≃Δ was injected into a superconductor with BCS gap Δ ; the subsequent postpump evolution was detected via the optical conductivity. It was argued that nonlinear coupling of the pump to the Anderson pseudospins of the superconductor induces coherent dynamics of the Higgs (amplitude) mode Δ (t ) . We validate this picture in a two-dimensional BCS model with a combination of exact numerics and the Lax reduction method, and we compute the nonequilibrium phase diagram as a function of the pump intensity. The main effect of the pump is to scramble the orientations of Anderson pseudospins along the Fermi surface by twisting them in the x y plane. We show that more intense pump pulses can induce a far-from-equilibrium phase of gapless superconductivity ("phase I"), originally predicted in the context of interaction quenches in ultracold atoms. We show that the THz pump method can reach phase I at much lower energy densities than an interaction quench, and we demonstrate that Lax reduction (tied to the integrability of the BCS Hamiltonian) provides a general quantitative tool for computing coherent BCS dynamics. We also calculate the Mattis-Bardeen optical conductivity for the nonequilibrium states discussed here.

Executive Function and Remission of Geriatric Depression: The Role of Semantic Strategy

PubMed Central

Morimoto, Sarah Shizuko; Gunning, Faith M.; Murphy, Christopher F.; Kanellopoulos, Dora; Kelly, Robert E.; Alexopoulos, George S.

2013-01-01

BACKGROUND This study tested the hypothesis that use of semantic organizational strategy in approaching the Mattis Dementia Rating Scale (MDRS) Complex Verbal Initiation Perseveration (I/P) task, a test of semantic fluency, is the function specifically associated with remission of late-life depression. METHOD 70 elders with major depression participated in a 12-week escitalopram treatment trial. Neuropsychological performance was assessed at baseline after a 2-week drug washout period. Patients with a Hamilton Depression Rating Scale Score less than or equal to 7 for two consecutive weeks and who no longer met DSM-IV criteria were considered to be remitted. Cox proportional hazards survival analysis was used to examine the relationship between subtests of the I/P, other neuropsychological domains and remission rate. Participants’ performance on the CV I/P was coded for perseverations, and use of semantic strategy. RESULTS The relationship of performance on the Complex Verbal I/P and remission rate was significant. No other subtest of the MDRS I/P evidenced this association. There was no significant relationship of speed, confrontation naming, verbal memory or perseveration with remission rate. Remitters’ use of verbal strategy was significantly greater than non-remitters. CONCLUSIONS Geriatric depressed patients who showed decrements in performance on a semantic fluency task showed poorer remission rates than those who showed adequate performance on this measure. Executive impairment in verbal strategy explained performance. This finding supports the concept that executive functioning exerts a “top down” effect on other basic cognitive processes, perhaps as a result of frontostriatal network dysfunction implicated in geriatric depression. PMID:20808124

Trait Neuroticism, Depression, and Cognitive Function in Older Primary Care Patients

PubMed Central

Boyle, Lisa L.; Lyness, Jeffrey M.; Duberstein, Paul R.; Karuza, Jurgis; King, Deborah A.; Messing, Susan; Tu, Xin

2010-01-01

Objective Prior studies on the association of trait neuroticism and cognitive function in older adults have yielded mixed findings. We tested hypotheses that neuroticism is associated with measures of cognition and that depression moderates these relationships. Design Cross-sectional observational study. Setting Primary care offices. Participants Primary care patients age ≥65 years. Measurements Trait neuroticism was assessed by the NEO-Five Factor Inventory. Major and minor depression (MDD, MinD) were determined by the Structured Clinical Interview for DSM-IV, and depressive symptom severity by the Hamilton Depression Rating Scale (Ham-D). Cognitive measures included the Mini-Mental State Examination (MMSE), Initiation-Perseveration subscale of the Mattis Dementia Rating Scale, and Trail-Making Tests A and B. Results In multiple regression analyses, neuroticism was associated with MMSE score independent of depression diagnosis (β = −0.04, χ2 = 14.2, df = 1, p = 0.0002, 95% CI = −0.07, −0.02) and Ham-D score (β = −0.04, χ2 = 8.97, df = 1, p = 0.003, 95% CI = −0.06, −0.01). Interactions between neuroticism and depression diagnosis (χ2 = 7.21, df = 2, p = 0.03) and Ham-D scores (χ2 = 0.55, df = 1, p = 0.46) failed to lend strong support to the moderation hypothesis. Conclusion Neuroticism is associated with lower MMSE scores. Findings do not confirm a moderating role for depression, but suggest that depression diagnosis may confer additional risk for poorer global cognitive function in patients with high neuroticism. Further study is necessary. PMID:20220585

Effectiveness of cognitive training for Chinese elderly in Hong Kong

PubMed Central

Kwok, Timothy; Wong, Anita; Chan, Grace; Shiu, YY; Lam, Ko-Chuen; Young, Daniel; Ho, Daniel WH; Ho, Florence

2013-01-01

In Hong Kong, the evidence for cognitive-training programs in fighting against memory complaints is lacking. This study aimed to evaluate the effectiveness of the Active Mind cognitive-training program in improving the cognitive function and quality of life (QoL) for local community-dwelling Chinese older adults. A total of 200 subjects were recruited from 20 different district elderly community centers (DECCs). Centers were randomly assigned into either the intervention group or control group. The intervention group underwent eight 1-hour sessions of cognitive training, while the control group were included in the usual group activities provided by the DECCs. Standardized neuropsychological tests (the Chinese version of Mattis Dementia Rating Scale [CDRS] and the Cantonese version of the Mini-Mental State Examination) and the QoL questionnaire SF12 were used to assess participants’ cognitive function and QoL before and after the trial. A total of 176 subjects completed the study. The intervention group showed greater improvement in the cognitive function measured by total CDRS score (treatment: 12.24 ± 11.57 vs control: 4.37 ± 7.99; P < 0.001) and QoL measured by total SF12 score (treatment: 7.82 ± 13.19 vs control: 3.18 ± 11.61; P = 0.014). Subjects with lower education level were associated with better cognitive response to the cognitive-training program. The current findings indicated that the Active Mind cognitive-training program was effective in improving the cognitive function and QoL for community-dwelling Chinese older adults in Hong Kong. PMID:23440076

Apathy in patients with Parkinson disease without dementia or depression: a PET study.

PubMed

Robert, Gabriel; Le Jeune, Florence; Lozachmeur, Clément; Drapier, Sophie; Dondaine, Thibault; Péron, Julie; Travers, David; Sauleau, Paul; Millet, Bruno; Vérin, Marc; Drapier, Dominique

2012-09-11

We sought to identify apathy metabolic bases in Parkinson disease (PD). A total of 45 patients with PD who were not clinically depressed (Montgomery-Åsberg Depression Rating Scale [MADRS] <21) and had no dementia (Mattis Dementia Rating Scale [MDRS] >130) were assessed with the Apathy Evaluation Scale (AES) and underwent a resting-state F-18 fluorodeoxyglucose PET (FDG-PET) scan. A motor assessment comprising the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) was conducted and total levodopa equivalent daily dose (LEDD) was calculated. Imaging data were analyzed with statistical parametric mapping. Age, LEDD, and MDRS scores were introduced as covariates. Positive correlations were observed between the AES score and cerebral metabolism in the right inferior frontal gyrus (Brodmann area [BA] 47), right middle frontal gyrus (BA 10), right cuneus (BA 18), and right anterior insula (BA 13). Negative correlations were observed between the AES score and cerebellar metabolism in the semilunar lobules bilaterally, within the posterior lobe. Using an AES score equal to or above 42 to define clinical apathy, prevalence in our patient group was 17.8%. The AES score was negatively correlated with the MDRS score and positively correlated with the "retardation" subscore of the MADRS. It was not correlated with either UPDRS III or LEDD. Results indicate that the frontal, temporal, and cerebellar areas known to be involved in reward, emotion, and cognition are also implicated in apathy in patients with PD without dementia or depression. Their roles in the etiopathology of apathy are discussed.

Apathy is related to cortex morphology in CADASIL. A sulcal-based morphometry study.

PubMed

Jouvent, E; Reyes, S; Mangin, J-F; Roca, P; Perrot, M; Thyreau, B; Hervé, D; Dichgans, M; Chabriat, H

2011-04-26

Apathy is a debilitating symptom in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the pathophysiology of which remains poorly understood. The aim of this study was to evaluate the neuroanatomic correlates of apathy, using new MRI postprocessing methods based on the identification of cortical sulci, in a large cohort of patients with CADASIL. A total of 132 patients with genetically confirmed diagnosis were included in this prospective cohort study. Global cognitive performances were assessed by the Mattis Dementia Rating Scale (MDRS) and disability by the modified Rankin score (mRS). Apathy was defined according to standard criteria. Depth, width, and cortical thickness of 10 large sulci of the frontal lobe in each hemisphere were measured. Logistic regression modeling was used to evaluate the links between apathy and cortical thickness, depth, or width of the different sulci. All models were adjusted for age, gender, level of education, MDRS, mRS, depression, and global brain volume. Complete MRI datasets of high quality were available in 119 patients. Depth of the posterior cingulate sulcus exhibited the strongest association with apathy in fully adjusted models (right: p value = 0.0006; left: p value = 0.004). Depth and width of cortical sulci in mediofrontal and orbitofrontal areas were independently associated with apathy. By contrast, cortical thickness was not. Cortical morphology in mediofrontal and orbitofrontal areas, by contrast to cortical thickness, is strongly and independently associated with apathy. These results suggest that apathy is related to a reduction of cortical surface rather than of cortical thickness secondary to lesion accumulation in CADASIL.

Neuropsychological Correlates of Capacity Determinations in Alzheimer’s Disease: Implications for Assessment

PubMed Central

Palmer, Barton W.; Ryan, Kerry A.; Kim, H. Myra; Karlawish, Jason H.; Appelbaum, Paul S.; Kim, Scott Y. H.

2011-01-01

Objectives To explore the neuropsychological correlates of the capacity to consent to research and to appoint a research proxy among persons with Alzheimer’s disease. Design, Setting, and Participants Interview study of 77 persons with Alzheimer’s disease recruited through an Alzheimer’s disease research center and a memory disorder clinic. Measurements The capacity to consent to two research scenarios (a drug randomized clinical trial and a neurosurgical clinical trial) and the capacity to appoint a research proxy were determined by five experienced consultation psychiatrists who rendered categorical judgments based on videotaped interviews of the MacArthur Competence Assessment Tool-Clinical Research (MacCAT-CR) and the Capacity to Appoint a Proxy Assessment (CAPA). Mattis Dementia Rating Scale-2 (DRS-2) was used to assess neuropsychological functioning. Results The capacity to appoint a proxy and to consent to the drug randomized clinical trial, as determined by a majority or greater opinion of the 5-psychiatrist panel, were predicted by Conceptualization and Initiation/Perseveration subscales whereas the capacity to consent to a neurosurgical randomized clinical trial was predicted by the Memory subscale. Furthermore, the more lenient individual psychiatrists’ judgments were predicted by the Conceptualization subscale whereas the stricter psychiatrists’ judgments were predicted by the Memory subscale. Conclusions How experienced psychiatrists view Alzheimer’s patients’ capacity for consenting to research and for appointing a proxy may be related to the patients’ conceptualization and memory functioning. More explicit and standardized guidance on the role of short term memory in capacity determinations may be useful. PMID:23498384

Problem-Solving Therapy Reduces Suicidal Ideation In Depressed Older Adults with Executive Dysfunction

PubMed Central

Gustavson, Kristen A.; Alexopoulos, George S; Niu, Grace C.; McCulloch, Charles; Meade, Tanya; Arean, Patricia A.

2017-01-01

Objective To test the hypothesis that Problem Solving Therapy (PST) is more effective than Supportive Therapy (ST) in reducing suicidal ideation in older adults with major depression and executive dysfunction. We further explored whether patient characteristics, such as age, gender and additional cognitive impairment load (eg: memory impairments) were related to changes in suicidal ideation over time. Design Secondary data analysis using data from a randomized clinical trial allocating participants to PST or ST at 1:1 ratio. Raters were blind to patients' assignments. Setting University medical centers. Participants 221 people aged 65 years old and older with major depression determined by SCID diagnosis and executive dysfunction as defined by a score of 33 or less on the Initiation-Perseveration Score of the Mattis Dementia Rating Scale or Stroop Interference Task score of 25 or less. Interventions 12 weekly sessions of Problem Solving Therapy or Supportive Therapy. Main Outcome Measures The suicide item of the Hamilton Depression Rating Scale (HDRS). Results Of the 221 participants, 61% reported suicidal ideation (SI). The ST group had a lower rate of improvement in SI after 12 weeks (44.6%) than did the PST group (60.4%, Fisher's exact test p = 0.031). Logistic regression showed significantly greater reductions in SI in elders who received PST at both 12 weeks (OR = .50, Z=-2.16, p = 0.031) and 36 weeks (OR=0.5, Z=-1.96, p=0.05) after treatment. Conclusion PST is a promising intervention for older adults who are at risk for suicide. PMID:26743100

PREFACE: First International Congress of the International Association of Inverse Problems (IPIA): Applied Inverse Problems 2007: Theoretical and Computational Aspects

NASA Astrophysics Data System (ADS)

Uhlmann, Gunther

2008-07-01

This volume represents the proceedings of the fourth Applied Inverse Problems (AIP) international conference and the first congress of the Inverse Problems International Association (IPIA) which was held in Vancouver, Canada, June 25 29, 2007. The organizing committee was formed by Uri Ascher, University of British Columbia, Richard Froese, University of British Columbia, Gary Margrave, University of Calgary, and Gunther Uhlmann, University of Washington, chair. The conference was part of the activities of the Pacific Institute of Mathematical Sciences (PIMS) Collaborative Research Group on inverse problems (http://www.pims.math.ca/scientific/collaborative-research-groups/past-crgs). This event was also supported by grants from NSF and MITACS. Inverse Problems (IP) are problems where causes for a desired or an observed effect are to be determined. They lie at the heart of scientific inquiry and technological development. The enormous increase in computing power and the development of powerful algorithms have made it possible to apply the techniques of IP to real-world problems of growing complexity. Applications include a number of medical as well as other imaging techniques, location of oil and mineral deposits in the earth's substructure, creation of astrophysical images from telescope data, finding cracks and interfaces within materials, shape optimization, model identification in growth processes and, more recently, modelling in the life sciences. The series of Applied Inverse Problems (AIP) Conferences aims to provide a primary international forum for academic and industrial researchers working on all aspects of inverse problems, such as mathematical modelling, functional analytic methods, computational approaches, numerical algorithms etc. The steering committee of the AIP conferences consists of Heinz Engl (Johannes Kepler Universität, Austria), Joyce McLaughlin (RPI, USA), William Rundell (Texas A&M, USA), Erkki Somersalo (Helsinki University of Technology, Finland), Masahiro Yamamoto (University of Tokyo, Japan), Gunther Uhlmann (University of Washington) and Jun Zou (Chinese University of Hong Kong). IPIA is a recently formed organization that intends to promote the field of inverse problem at all levels. See http://www.inverse-problems.net/. IPIA awarded the first Calderón prize at the opening of the conference to Matti Lassas (see first article in the Proceedings). There was also a general meeting of IPIA during the workshop. This was probably the largest conference ever on IP with 350 registered participants. The program consisted of 18 invited speakers and the Calderón Prize Lecture given by Matti Lassas. Another integral part of the program was the more than 60 mini-symposia that covered a broad spectrum of the theory and applications of inverse problems, focusing on recent developments in medical imaging, seismic exploration, remote sensing, industrial applications, numerical and regularization methods in inverse problems. Another important related topic was image processing in particular the advances which have allowed for significant enhancement of widely used imaging techniques. For more details on the program see the web page: http://www.pims.math.ca/science/2007/07aip. These proceedings reflect the broad spectrum of topics covered in AIP 2007. The conference and these proceedings would not have happened without the contributions of many people. I thank all my fellow organizers, the invited speakers, the speakers and organizers of mini-symposia for making this an exciting and vibrant event. I also thank PIMS, NSF and MITACS for their generous financial support. I take this opportunity to thank the PIMS staff, particularly Ken Leung, for making the local arrangements. Also thanks are due to Stephen McDowall for his help in preparing the schedule of the conference and Xiaosheng Li for the help in preparing these proceedings. I also would like to thank the contributors of this volume and the referees. Finally, many thanks are due to Graham Douglas and Elaine Longden-Chapman for suggesting publication in Journal of Physics: Conference Series.

Einleitung

NASA Astrophysics Data System (ADS)

Ha, Suk-Woo; Wintermantel, Erich

Der Aufbau des menschlichen Körpers ist derart komplex, dass die vollständige funktionelle Substitution seiner Strukturen mit künstlichen Werkstoffen und Bauteilen unwahrscheinlich ist. Die meisten heute klinisch eingesetzten Implantate ersetzen in der Regel einfache mechanische oder andere physikalische Funktionen des menschlichen Körpers, die aufgrund eines singulären Defektes im Gewebe oder als Ergebnis einer chronischen Erkrankung substituiert werden müssen. Gelenkprothesen beispielsweise übertragen Lasten, eine künstliche intraokulare Linse ermöglicht Lichttransmission und eine künstliche Arterie sorgt für die Aufrechterhaltung der Blutversorgung. Neben der Funktionserfüllung müssen die medizinisch eingesetzten Werkstoffe zusätzlich den Anforderungen der Körperverträglichkeit genügen, die die vollständige und dauerhafte Aufnahme des Implantates im Körper zum Ziel hat. Die Erkenntnisse der Werkstoffwissenschaft und deren Umsetzung in neue Produkte hat die Entwicklung und Fortschritte in der Medizin und in der Chirurgie entscheidend geprägt. Werkstoffe stehen in ihrem klinischen Einsatz als Temporärimplantate (z. B. Kathetersysteme) sowie als Langzeitimplantate (z. B. Hüftgelenksimplantate oder Herzschrittmacher) in direktem Kontakt mit den Geweben des Körpers und müssen deshalb biokompatibel sein.

Saturn Apollo Program

NASA Image and Video Library

1969-07-16

Chief astronaut and director of flight crew operations, Donald K. Slayton (right front) reviews lunar charts with Apollo 11 astronauts Michael Collins (left), Neil Armstrong, and Edwin Aldrin (next to Slayton) during breakfast a short time before the three men launched for the first Moon landing mission. Sharing breakfast with the crew was William Anders (left rear), Lunar Module pilot for the Apollo 8 lunar orbit mission. The Apollo 11 mission launched from the NASA Kennedy Space Center (KSC) in Florida via the Marshall Space Flight Center (MSFC) developed Saturn V launch vehicle on July 16, 1969 and safely returned to Earth on July 24, 1969. The CM, “Columbia”, piloted by Collins, remained in a parking orbit around the Moon while the LM, “Eagle’’, carrying astronauts Armstrong and Aldrin, landed on the Moon. On July 20, 1969, Armstrong was the first human to ever stand on the lunar surface, followed by Aldrin. During 2½ hours of surface exploration, the crew collected 47 pounds of lunar surface material for analysis back on Earth. With the success of Apollo 11, the national objective to land men on the Moon and return them safely to Earth had been accomplished.

Body mass and antler development patterns of Rocky Mountain elk (Cervus elaphus nelsoni) in Michigan

USGS Publications Warehouse

Bender, L.C.; Carlson, E.; Schmitt, S.M.; Haufler, J.B.

2003-01-01

We documented mean and maximum body mass, mass accretion patterns and ander development patterns of Rocky Mountain elk in Michigan. Mean body mass of bulls averaged 9-11% heavier, and maximum body mass 23-27% heavier, in Michigan than in other Rocky Mountain elk populations. Mean live body mass of cows averaged 11% heavier in Michigan, but mean eviscerated body mass did not differ. Maximum body mass of cows was 10-24% heavier in Michigan. Body mass peaked at age 7.5 for bulls and 8.5 for cows, similar to other Rocky Mountain elk populations despite the greater body mass achieved in Michigan. Sexual dimorphism in bull and cow body mass increased until peak body mass was attained, whereupon bulls were ???38% heavier than cows. Antler development of bull elk peaked at age 10.5, comparable to other Rocky Mountain elk populations. Relations between antler development and body mass within age classes were highly variable, but generally weak. Greater body mass seen in Michigan, and the peaking of antler development well after body mass in bulls, suggested a phenotypic response to nutritional conditions that allow Rocky Mountain elk in Michigan to maximize the species growth potential.

Self-assembling amphiphilic molecules: Synthesis in simulated interstellar/precometary ices

PubMed Central

Dworkin, Jason P.; Deamer, David W.; Sandford, Scott A.; Allamandola, Louis J.

2001-01-01

Interstellar gas and dust constitute the primary material from which the solar system formed. Near the end of the hot early phase of star and planet formation, volatile, less refractory materials were transported into the inner solar system as comets and interplanetary dust particles. Once the inner planets had sufficiently cooled, late accretionary infall seeded them with complex organic compounds [Oró, J. (1961) Nature (London) 190, 389–390; Delsemme, A. H. (1984) Origins Life 14, 51–60; Anders, E. (1989) Nature (London) 342, 255–257; Chyba, C. F. & Sagan, C. (1992) Nature (London) 355, 125–131]. Delivery of such extraterrestrial compounds may have contributed to the organic inventory necessary for the origin of life. Interstellar ices, the building blocks of comets, tie up a large fraction of the biogenic elements available in molecular clouds. In our efforts to understand their synthesis, chemical composition, and physical properties, we report here that a complex mixture of molecules is produced by UV photolysis of realistic, interstellar ice analogs, and that some of the components have properties relevant to the origin of life, including the ability to self-assemble into vesicular structures. PMID:11158552

Bilateral subthalamic or pallidal stimulation for Parkinson's disease affects neither memory nor executive functions: a consecutive series of 62 patients.

PubMed

Ardouin, C; Pillon, B; Peiffer, E; Bejjani, P; Limousin, P; Damier, P; Arnulf, I; Benabid, A L; Agid, Y; Pollak, P

1999-08-01

There is a renewal of interest in surgical approaches including lesions and deep brain stimulation directed at motor subcorticofrontal loops. Bilateral lesioning presents a far greater risk of adverse effects, especially cognitive impairment. Furthermore, the main advantages of the stimulation procedure over lesioning are adaptability and reversibility of effects. The aim of this study was to assess the influence of bilateral stimulation of the subthalamic nucleus or internal globus pallidus on memory and executive functions in Parkinson's disease. Sixty-two patients were assessed before and after 3 to 6 months of chronic bilateral stimulation of the subthalamic nucleus (n = 49) or internal globus pallidus (n = 13). The neuropsychological tests used were the Mattis Dementia Rating Scale, the Grober and Buschke Verbal Learning Test, the Wisconsin Card Sorting Test, category and literal fluency, graphic and motor series, the Stroop Test, and the Trail Making Test. Mood was evaluated by the Beck Depression Inventory. Only 4 of 25 cognitive variables were affected by deep brain stimulation. Under stimulation, performance improved for Parts A and B of the Trail Making Test, but there was a deterioration in literal and total lexical fluency. There was also a mild but significant improvement in mood. It may therefore be concluded that stimulation of the subthalamic nucleus or internal globus pallidus does not change the overall cognitive performance in Parkinson's disease and does not greatly affect the functioning of subcorticofrontal loops involved in cognition in humans. This relative absence of cognitive impairment in bilateral deep brain stimulation is likely because of the accurate positioning of the electrodes, allowing the effects of stimulation to be confined to sensorimotor circuits.

The Structure and Molecular Parameters of Camphene Determined by Fourier Transform Microwave Spectroscopy and Quantum Chemical Calculations

NASA Astrophysics Data System (ADS)

Neeman, Elias M.; Dréan, Pascal; Huet, T. R.

2016-06-01

The emission of volatile organic compounds, from plants has strong revelance for plant physiology, plant ecology and atmospheric chemistry. Camphene (C10H16) is a bicyclic monoterpene which is emitted in the atmosphere by biogenic sources. The structure of the unique stable conformer was optimized using density functional theory and ab initio calculations. The rotational spectrum of camphene was recorded in a supersonic jet expansion with a Fourier transform microwave spectrometer over the range 2-20 GHz. Signals from the parent species and from the ten 13C isotopomers were observed in natural abundance. The rotational and centrifugal distortion parameters were fitted to a Watson's Hamiltonian in the A-reduction. A magnetic hyperfine structure associated with the pairs of hydrogen nuclei in the methylene groups was observed and modeled.The rotational constants coupled to the equilibrium structure calculations were used to determine the r_0 and the r_m(1) gas-phase geometries of the carbon skeleton. The present work provides the first spectroscopic characterization of camphene in the gas phase and these results are also relevant for ozonolysis kinetics study through Criegee intermediates. R. Baraldi, F. Rapparini, O. Facini, D. Spano and P. Duce, Journal of Mediterranean Ecology, Vol.6, No.1, (2005). A. Bracho-Nunez, N. M. Knothe, S. Welter, M. Staudt, W. R. Costa, M. A. R. Liberato, M. T. F. Piedade, and J. Kesselmeier Biogeosciences, 10, 5855-5873, (2013). Minna Kivimäenpää, Narantsetseg Magsarjav, Rajendra Ghimire, Juha-Matti Markkanen, Juha Heijari, Martti Vuorinen and Jarmo K. Holopainen, Atmospheric Environment, 60, 477-485, (2012). R.C. de M. Oliveira and G. F. Bauerfeldt, J. Phys. Chem. A, 119 2802-2812 (2015)

Imaging Findings Associated with Cognitive Performance in Primary Lateral Sclerosis and Amyotrophic Lateral Sclerosis

PubMed Central

Meoded, Avner; Kwan, Justin Y.; Peters, Tracy L.; Huey, Edward D.; Danielian, Laura E.; Wiggs, Edythe; Morrissette, Arthur; Wu, Tianxia; Russell, James W.; Bayat, Elham; Grafman, Jordan; Floeter, Mary Kay

2013-01-01

Introduction Executive dysfunction occurs in many patients with amyotrophic lateral sclerosis (ALS), but it has not been well studied in primary lateral sclerosis (PLS). The aims of this study were to (1) compare cognitive function in PLS to that in ALS patients, (2) explore the relationship between performance on specific cognitive tests and diffusion tensor imaging (DTI) metrics of white matter tracts and gray matter volumes, and (3) compare DTI metrics in patients with and without cognitive and behavioral changes. Methods The Delis-Kaplan Executive Function System (D-KEFS), the Mattis Dementia Rating Scale (DRS-2), and other behavior and mood scales were administered to 25 ALS patients and 25 PLS patients. Seventeen of the PLS patients, 13 of the ALS patients, and 17 healthy controls underwent structural magnetic resonance imaging (MRI) and DTI. Atlas-based analysis using MRI Studio software was used to measure fractional anisotropy, and axial and radial diffusivity of selected white matter tracts. Voxel-based morphometry was used to assess gray matter volumes. The relationship between diffusion properties of selected association and commissural white matter and performance on executive function and memory tests was explored using a linear regression model. Results More ALS than PLS patients had abnormal scores on the DRS-2. DRS-2 and D-KEFS scores were related to DTI metrics in several long association tracts and the callosum. Reduced gray matter volumes in motor and perirolandic areas were not associated with cognitive scores. Conclusion The changes in diffusion metrics of white matter long association tracts suggest that the loss of integrity of the networks connecting fronto-temporal areas to parietal and occipital areas contributes to cognitive impairment. PMID:24052798

Changes in Brain Volume and Cognition in a Randomized Trial of Exercise and Social Interaction in a Community-Based Sample of Non-Demented Chinese Elders

PubMed Central

Mortimer, James A.; Ding, Ding; Borenstein, Amy R.; DeCarli, Charles; Guo, Qihao; Wu, Yougui; Zhao, Qianhua; Chu, Shugang

2013-01-01

Physical exercise has been shown to increase brain volume and improve cognition in randomized trials of non-demented elderly. Although greater social engagement was found to reduce dementia risk in observational studies, randomized trials of social interventions have not been reported. A representative sample of 120 elderly from Shanghai, China was randomized to four groups (Tai Chi, Walking, Social Interaction, No Intervention) for 40 weeks. Two MRIs were obtained, one before the intervention period, the other after. A neuropsychological battery was administered at baseline, 20 weeks, and 40 weeks. Comparison of changes in brain volumes in intervention groups with the No Intervention group were assessed by t-tests. Time-intervention group interactions for neuropsychological measures were evaluated with repeated-measures mixed models. Compared to the No Intervention group, significant increases in brain volume were seen in the Tai Chi and Social Intervention groups (p < 0.05). Improvements also were observed in several neuropsychological measures in the Tai Chi group, including the Mattis Dementia Rating Scale score (p = 0.004), the Trailmaking Test A (p = 0.002) and B (p = 0.0002), the Auditory Verbal Learning Test (p = 0.009), and verbal fluency for animals (p = 0.01). The Social Interaction group showed improvement on some, but fewer neuropsychological indices. No differences were observed between the Walking and No Intervention groups. The findings differ from previous clinical trials in showing increases in brain volume and improvements in cognition with a largely non-aerobic exercise (Tai Chi). In addition, intellectual stimulation through social interaction was associated with increases in brain volume as well as with some cognitive improvements. PMID:22451320

Cognitive impairment and PD patients' capacity to consent to research

PubMed Central

Cary, Mark; Moelter, Stephen T.; Siderowf, Andrew; Sullo, Elizabeth; Xie, Sharon; Weintraub, Daniel

2013-01-01

Objective: To examine how cognitive impairment affects Parkinson disease (PD) patients' research consent capacity. Methods: A cross-sectional study of 90 patients with PD, divided using Mattis Dementia Rating Scale–2 scores into 3 groups of 30 (normal, borderline, and impaired), and 30 neurologically normal older adults completed 2 capacity interviews (an early-phase randomized and controlled drug trial and a sham-controlled surgical implantation of genetic tissue) using the MacArthur Competence Assessment Tool for Clinical Research. Expert clinicians used the interviews to classify the patients as either capable or not capable of providing their own informed consent. These judgments were compared with performance on the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE). Results: Cognitively normal PD patients typically scored well on the capacity measures. In contrast, patients with impaired cognition were not capable of providing their own informed consent: 17% (5/30) on the drug trial and 3% (1/30) on the surgery trial were judged capable. Patients with borderline impairment showed adequate performance on measures of appreciation and reasoning, but impaired performance on understanding the drug trial compared with normal controls and normal PD patients, and on understanding the surgery trial compared with normal controls. Sixty-seven percent (20/30) on the drug trial and 57% (17/30) on the surgery trial were judged capable of consent. Receiver operating characteristic analyses showed that the MMSE and MoCA could detect the likelihood of impaired capacity, with the MoCA demonstrating greater sensitivity. Conclusions: PD patients with borderline cognitive impairment have impairments in their decisional capacity. The MoCA may be useful to identify the patients at risk of impaired capacity. PMID:23892706

Genetic influences on cognitive decline in Parkinson's disease

PubMed Central

Morley, J.F.; Xie, S.X.; Hurtig, H.I.; Stern, M.B.; Colcher, A.; Horn, S.; Dahodwala, N.; Duda, J.E.; Weintraub, D.; Chen-Plotkin, A.S.; Van Deerlin, V.; Falcone, D.; Siderowf, A.

2012-01-01

Background The role of genetic factors in cognitive decline associated with Parkinson's disease is unclear. We examined whether variations in apolipoprotein E, microtubule-associated protein tau or catechol-O-methytransferase genotypes are associated with cognitive decline in Parkinson's disease. Methods We performed a prospective cohort study of 212 patients with a clinical diagnosis of Parkinson's disease. The primary outcome was change in Mattis Dementia Rating Scale version 2 score. Linear mixed-effects models and survival analysis were used to test for associations between genotypes and change in cognitive function over time. Results The ε4 allele of apoliporotein E was associated with more rapid decline (loss of 2.9 (95% CI, 1.7–4.1) more points/year, p<0.001) in total score and an increased risk of a ≥10 pointdrop during the follow-up period (HR 2.8, 95% CI 1.4–5.4, p=0.003). Microtubule-associated protein tau haplotype and catechol-O-methytransferase genotype were associated with measures of memory and attention, respectively, over the entire followup period but not with the overall rate of cognitive decline. Conclusion These results confirm and extend previously described genetic associations with cognitive decline in Parkinson's disease and imply that individual genes may exert effects on specific cognitive domains or at different disease stages. Carrying at least one apolipoprotein E ε4 allele is associated with more rapid cognitive decline in Parkinson's disease, supporting the idea of a component of shared etiology between Parkinson's disease dementia and Alzheimer disease. Clinically, these results suggest genotyping can provide information about the risk of future cognitive decline for Parkinson's disease patients. PMID:22344634

Memory, Mood, and Vitamin D in Persons with Parkinson’s Disease

PubMed Central

Peterson, Amie L.; Murchison, Charles; Zabetian, Cyrus; Leverenz, James B.; Watson, G. Stennis; Montine, Thomas; Carney, Natasha; Bowman, Gene L.; Edwards, Karen; Quinn, Joseph F.

2014-01-01

Background Research in recent years has suggested a role of vitamin D in the central nervous system. The final converting enzyme and the vitamin D receptor are found throughout the human brain. From animal studies vitamin D appears important in neurodevelopment, up-regulation of neurotrophic factors, stabilization of mitochondrial function, and antioxidation. Objective To examine the relationship between serum vitamin D and neuropsychiatric function in persons with Parkinson’s disease (PD). Methods This is an add-on study to a longitudinal study following neuropsychiatric function in persons with PD. Baseline neuropsychiatric performance and serum 25-hydroxyvitamin D were examined for 286 participants with PD. Measures of global cognitive function (MMSE, MOCA, Mattis Dementia Scale), verbal memory (Hopkins Verbal Learning Test), fluency (animals, vegetables, and FAS words), visuospatial function (Benton Line Orientation), executive function (Trails Making Test and Digit-Symbol Substitution), PD severity (Hoehn & Yahr and Unified Parkinson’s Disease Rating Scale) and depression (Geriatric Depression Scale (GDS)) were administered. Multivariate linear regression assessed the association between vitamin D concentration and neuropsychiatric function, in the entire cohort as well as the non-demented and demented subsets. Results Using a multivariate model, higher vitamin concentrations were associated with better performance on numerous neuropsychiatric tests in the non-demented subset of the cohort. Significant associations were specifically found between vitamin D concentration and verbal fluency and verbal memory (t = 4.31, p < 0.001 and t = 3.04, p = 0.0083). Vitamin D concentrations also correlated with depression scores (t =−3.08, p = 0.0083) in the non-demented subset. Conclusions Higher plasma vitamin D is associated with better cognition and better mood in this sample of PD patients without dementia. Determination of causation will require a vitamin D intervention study. PMID:24081441

Application of Bogolyubov's theory of weakly nonideal Bose gases to the A+A, A+B, B+B reaction-diffusion system

NASA Astrophysics Data System (ADS)

Konkoli, Zoran

2004-01-01

Theoretical methods for dealing with diffusion-controlled reactions inevitably rely on some kind of approximation, and to find the one that works on a particular problem is not always easy. Here the approximation used by Bogolyubov to study a weakly nonideal Bose gas, referred to as the weakly nonideal Bose gas approximation (WBGA), is applied in the analysis of three reaction-diffusion models: (i) A+A→Ø, (ii) A+B→Ø, and (iii) A+A,B+B,A+B→Ø (the ABBA model). Two types of WBGA are considered, the simpler WBGA-I and the more complicated WBGA-II. All models are defined on the lattice to facilitate comparison with computer experiment (simulation). It is found that the WBGA describes the A+B reaction well, it reproduces the correct d/4 density decay exponent. However, it fails in the case of the A+A reaction and the ABBA model. (To cure the deficiency of WBGA in dealing with the A+A model, a hybrid of the WBGA and Kirkwood superposition approximations is suggested.) It is shown that the WBGA-I is identical to the dressed-tree calculation suggested by Lee [J. Phys. A 27, 2633 (1994)], and that the dressed-tree calculation does not lead to the d/2 density decay exponent when applied to the A+A reaction, as normally believed, but it predicts the d/4 decay exponent. Last, the usage of the small n0 approximation suggested by Mattis and Glasser [Rev. Mod. Phys. 70, 979 (1998)] is questioned if used beyond the A+B reaction-diffusion model.

Renormalization Group Studies and Monte Carlo Simulation for Quantum Spin Systems.

NASA Astrophysics Data System (ADS)

Pan, Ching-Yan

We have discussed the extended application of various real space renormalization group methods to the quantum spin systems. At finite temperature, we extended both the reliability and range of application of the decimation renormalization group method (DRG) for calculating the thermal and magnetic properties of low-dimensional quantum spin chains, in which we have proposed general models of the three-state Potts model and the general Heisenberg model. Some interesting finite-temperature behavior of the models has been obtained. We also proposed a general formula for the critical properties of the n-dimensional q-state Potts model by using a modified migdal-Kadanoff approach which is in very good agreement with all available results for general q and d. For high-spin systems, we have investigated the famous Haldane's prediction by using a modified block renormalization group approach in spin -1over2, spin-1 and spin-3 over2 cases. Our result supports Haldane's prediction and a novel property of the spin-1 Heisenberg antiferromagnet has been predicted. A modified quantum monte Carlo simulation approach has been developed in this study which we use to treat quantum interacting problems (we only work on quantum spin systems in this study) without the "negative sign problem". We also obtain with the Monte Carlo approach the numerical derivative directly. Furthermore, using this approach we have obtained the energy spectrum and the thermodynamic properties of the antiferromagnetic q-state Potts model, and have studied the q-color problem with the result which supports Mattis' recent conjecture of entropy for the n -dimensional q-state Potts antiferromagnet. We also find a general solution for the q-color problem in d dimensions.

Herpes Simplex Encephalitis: Lack of Clinical Benefit of Long-term Valacyclovir Therapy.

PubMed

Gnann, John W; Sköldenberg, Birgit; Hart, John; Aurelius, Elisabeth; Schliamser, Silvia; Studahl, Marie; Eriksson, Britt-Marie; Hanley, Daniel; Aoki, Fred; Jackson, Alan C; Griffiths, Paul; Miedzinski, Lil; Hanfelt-Goade, Diane; Hinthorn, Daniel; Ahlm, Clas; Aksamit, Allen; Cruz-Flores, Salvador; Dale, Ilet; Cloud, Gretchen; Jester, Penelope; Whitley, Richard J

2015-09-01

Despite the proven efficacy of acyclovir (ACV) therapy, herpes simplex encephalitis (HSE) continues to cause substantial morbidity and mortality. Among patients with HSE treated with ACV, the mortality rate is approximately 14%-19%. Among survivors, 45%-60% have neuropsychological sequelae at 1 year. Thus, improving therapeutic approaches to HSE remains a high priority. Following completion of a standard course of intravenous ACV, 87 adult patients with HSE (confirmed by positive polymerase chain reaction [PCR] for herpes simplex virus DNA in cerebrospinal fluid) were randomized to receive either valacyclovir (VACV) 2 g thrice daily (n = 40) or placebo tablets (n = 47) for 90 days (12 tablets of study medication daily). The primary endpoint was survival with no or mild neuropsychological impairment at 12 months, as measured by the Mattis Dementia Rating Scale (MDRS). Logistic regression was utilized to assess factors related to the primary endpoint. The demographic characteristics of the 2 randomization groups were statistically similar with no significant differences in age, sex, or race. At 12 months, there was no significant difference in the MDRS scoring for VACV-treated vs placebo recipients, with 85.7% and 90.2%, respectively, of patients demonstrating no or mild neuropsychological impairment (P = .72). No significant study-related adverse events were encountered in either treatment group. Following standard treatment with intravenous ACV for PCR-confirmed HSE, an additional 3-month course of oral VACV therapy did not provide added benefit as measured by neuropsychological testing 12 months later in a population of relatively high-functioning survivors. NCT00031486. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Neuropsychological and clinical heterogeneity of cognitive impairment in patients with multiple system atrophy.

PubMed

Barcelos, Lorena Broseghini; Saad, Flávia; Giacominelli, Carla; Saba, Roberta Arb; de Carvalho Aguiar, Patrícia Maria; Silva, Sonia Maria Azevedo; Borges, Vanderci; Bertolucci, Paulo Henrique Ferreira; Ferraz, Henrique Ballalai

2018-01-01

We evaluated neuropsychological tests to compare cognitive impairment between two types of multiple system atrophy: predominant parkinsonism (MSA-P) and predominant cerebellar ataxia (MSA-C). This cross-sectional study included 14 patients diagnosed with MSA: four with MSA-C and ten with MSA-P. Presence of motor symptoms was determined by using the Unified Rating MSA Scale (URMSAS). Non-motor symptoms were evaluated by the Short Form Health Survey (SF-36), Scales for Outcomes in Parkinson's disease Autonomic (SCOPA-AUT), Hospital Anxiety and Depression Scale (HADS), and Beck Depression Inventory (BDI). Neuropsychological tests were used to evaluate general cognition, verbal and visual memory, working memory, constructional ability, visuospatial, language, and executive function. The median age of the patients was 62 years, median disease duration was 3.5 years, and median education level was 10 years. The median Mini-Mental State Examination (MMSE) score was 26.5 points, and median Mattis Dementia Rating Scale (MDRS) score was 131.5. We compared the continuous data between the two MSA subtypes and observed that bodily pain reported in the quality of life questionnaire, SF-36, was worse in MSA-P (p<0.05), and attention function evaluated by MDRS was significantly lower in MSA-C than MSA-P (p<0.05). Our comparative study of cognitive impairment in MSA-P and MSA-C showed that both groups had impaired executive and visuospatial functions, while the attention deficit was predominant only in MSA-C. These findings support the concept that cognitive deficit originates from striatofrontal dysfunction and cerebellar degeneration. Our study also suggests that cognitive impairment is relevant in MSA, and clinical neurologists should not neglect evaluation of these aspects in their daily clinical practice. Copyright © 2017. Published by Elsevier B.V.

Predictors of performance-based measures of instrumental activities of daily living in nondemented patients with Parkinson's disease.

PubMed

Pirogovsky, Eva; Martinez-Hannon, Mercedes; Schiehser, Dawn M; Lessig, Stephanie L; Song, David D; Litvan, Irene; Filoteo, J Vincent

2013-01-01

Few studies have examined instrumental activities of daily living (iADLs) in nondemented Parkinson's disease (PD), and the majority of these studies have used report-based measures, which can have limited validity. The present study had two main goals: (a) to examine the performance of nondemented PD patients on two performance-based measures of iADLs, which are considered more objective functional measures, and (b) to examine the cognitive, motor, and psychiatric correlates of iADL impairment in PD. Ninety-eight nondemented PD patients and 47 healthy older adults were administered performance-based measures that assess the ability to manage medications (Medication Management Ability Assessment) and finances (University of California, San Diego, UCSD, Performance-based Skills Assessment), the Mattis Dementia Rating Scale to assess global cognitive functioning, the Unified Parkinson's Disease Rating Scale Part III to assess motor symptom severity, and the Geriatric Depression Scale to assess depressive symptoms. Nondemented PD patients demonstrated significantly impaired scores relative to the healthy comparison group on the performance-based measure of financial management, but there were no significant group differences in medication management. Global cognitive functioning, motor severity, and depressive symptoms did not correlate with scores on either of the functional measures, except for a small correlation between depressive symptoms and financial management. The two performance-based measures of iADL functioning did not correlate with one another. These findings suggest that medication and financial management may not be predicted based on global cognitive functioning and that iADLs may not be represented by a single construct. Furthermore, these findings suggest the potential need for a multidimensional approach to assessing iADLs.

Changes in brain volume and cognition in a randomized trial of exercise and social interaction in a community-based sample of non-demented Chinese elders.

PubMed

Mortimer, James A; Ding, Ding; Borenstein, Amy R; DeCarli, Charles; Guo, Qihao; Wu, Yougui; Zhao, Qianhua; Chu, Shugang

2012-01-01

Physical exercise has been shown to increase brain volume and improve cognition in randomized trials of non-demented elderly. Although greater social engagement was found to reduce dementia risk in observational studies, randomized trials of social interventions have not been reported. A representative sample of 120 elderly from Shanghai, China was randomized to four groups (Tai Chi, Walking, Social Interaction, No Intervention) for 40 weeks. Two MRIs were obtained, one before the intervention period, the other after. A neuropsychological battery was administered at baseline, 20 weeks, and 40 weeks. Comparison of changes in brain volumes in intervention groups with the No Intervention group were assessed by t-tests. Time-intervention group interactions for neuropsychological measures were evaluated with repeated-measures mixed models. Compared to the No Intervention group, significant increases in brain volume were seen in the Tai Chi and Social Intervention groups (p < 0.05). Improvements also were observed in several neuropsychological measures in the Tai Chi group, including the Mattis Dementia Rating Scale score (p = 0.004), the Trailmaking Test A (p = 0.002) and B (p = 0.0002), the Auditory Verbal Learning Test (p = 0.009), and verbal fluency for animals (p = 0.01). The Social Interaction group showed improvement on some, but fewer neuropsychological indices. No differences were observed between the Walking and No Intervention groups. The findings differ from previous clinical trials in showing increases in brain volume and improvements in cognition with a largely non-aerobic exercise (Tai Chi). In addition, intellectual stimulation through social interaction was associated with increases in brain volume as well as with some cognitive improvements.

Elevated cerebrospinal fluid pressure in patients with Alzheimer's disease

PubMed Central

Silverberg, Gerald; Mayo, Martha; Saul, Thomas; Fellmann, Jere; McGuire, Dawn

2006-01-01

Background Abnormalities in cerebrospinal fluid (CSF) production and turnover, seen in normal pressure hydrocephalus (NPH) and in Alzheimer's disease (AD), may be an important cause of amyloid retention in the brain and may relate the two diseases. There is a high incidence of AD pathology in patients being shunted for NPH, the AD-NPH syndrome. We now report elevated CSF pressure (CSFP), consistent with very early hydrocephalus, in a subset of AD patients enrolled in a clinical trial of chronic low-flow CSF drainage. Our objective was to determine the frequency of elevated CSFP in subjects meeting National Institutes of Neurological and Communicative Diseases and Stroke – Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria for AD, excluding those with signs of concomitant NPH. Methods AD subjects by NINCDS-ADRDA criteria (n = 222), were screened by history, neurological examination, and radiographic imaging to exclude those with clinical or radiographic signs of NPH. As part of this exclusion process, opening CSFP was measured supine under general anesthesia during device implantation surgery at a controlled pCO2 of 40 Torr (40 mmHg). Results Of the 222 AD subjects 181 had pressure measurements recorded. Seven subjects (3.9%) enrolled in the study had CSFP of 220 mmH20 or greater, mean 249 ± 20 mmH20 which was significantly higher than 103 ± 47 mmH2O for the AD-only group. AD-NPH patients were significantly younger and significantly less demented on the Mattis Dementia Rating Scale (MDRS). Conclusion Of the AD subjects who were carefully screened to exclude those with clinical NPH, 4% had elevated CSFP. These subjects were presumed to have the AD-NPH syndrome and were withdrawn from the remainder of the study. PMID:16737542

Biokompatible Metalle

NASA Astrophysics Data System (ADS)

Ha, Suk-Woo; Wintermantel, Erich

Metalle als Implantatwerkstoffe werden in der Medizin für zwei Hauptanwendungen eingesetzt: für Prothesen des totalen Gelenkersatzes wie beispielsweise Hüft-, Knie- und Schulterprothesen und für Fixationselemente zur Stabilisierung von Frakturen. Beispiele hierfür sind Osteosyntheseplatten, Marknägel, Schrauben, Drähte und Stents. Eine der ersten Anwendungen von Metallen im menschlichen Körper war die Fixation von Fragmenten eines gebrochenen Humerus (Oberarmknochen) mit einem Metalldraht durch zwei französische Physiker im Jahr 1775 [1]. Ausführliche Untersuchungen zur Verträglichkeit von Metallen im menschlichen Körper wurden bereits im frühen 19. Jahrhundert durchgeführt. Von den untersuchten Werkstoffen verursachten die edlen Metalle wie Gold, Silber und Platin aufgrund ihrer Korrosionsbeständigkeit und Körperverträglichkeit die geringsten Reizungen im menschlichen Körper. Die klinische Anwendung der Edelmetalle war jedoch wegen der geringen mechanischen Eigenschaften beschränkt. Andere Metalle wie Messing, Kupfer oder Eisen wiesen vergleichsweise höhere Festigkeitswerte auf, sie waren jedoch aufgrund der geringen Korrosionsbeständigkeit und Biokompatibilität nicht für den klinischen Einsatz geeignet. Ein weiteres Problem stellte die Gefahr der Infektion durch unsterile Instrumente und Implantate dar. Gegen Ende des 19. Jahrhunderts hielt die antiseptische Operationsmethode Einzug in die Kliniken, die z. B. erfolgreiche Operationen mit Silberdraht ermöglichte.

Phylogenetic relationship of asam gelugur (Garcinia atroviridis Griff. ex T. Anders) based on morphological characters in Langkat and Serdang Berdagai, Sumatera Utara

NASA Astrophysics Data System (ADS)

Bayu, E. S.; Lestami, A.; Kardhinata, E. H.; Rosemary

2018-02-01

Garcinia atroviridis plant is a commodity that has the potential to become an export commodity in Sumatera Utara. Characterization is an activity in germplasm to determine the morphological properties that can be utilized in differentiating between accessions and assessing the magnitude of genetic diversity. The magnitude of genetic diversity based on morphological properties can support breeding programs. The research was conducted in several areas of G. atroviridis plant, i.e. Gebang, Bahorok, Padang Tualang, Pegajahan, Sei Rampah, Pantai Cermin, and Perbaungan sub-districts in September 2016 with direct observation method. The aim of this research is to explore and characterization between G. atroviridis plant in Langkat and Serdang Berdagai. Parameters morphology characters were observed based on IPGRI, and observation data were analyzed by using SPSS version 21 to obtain the dendogram. The dendogram results showed that there are four groups of kinship relationships on the scale of the spacing (euclidean distance scale) 17. The lowest unequal value (closest kinship) in accessions G3(Bahorok) and G7(Sei Rampah) is 16.328 while the highest value of inequality (farthest kinship) in G5( Padang Tualang) and G6 (Pegajahan) is equal to 54.187. It needs the conservation of G. atroviridis although must be done next observation.

Wissenschaft, die unsere Kultur verändert. Tiefenschichten des Streits um die Evolutionstheorie

NASA Astrophysics Data System (ADS)

Patzelt, Werner J.

Die Evolutionstheorie ist eine der erfolgreichsten wissenschaftlichen Theorien. Sie erlaubt es, unsere Herkunft zu verstehen und riskante Merkmale gerade der menschlichen Spezies zu begreifen. Zugleich ist die Evolutionstheorie eine der umstrittensten Theorien. Das liegt nicht an ihrer empirischen Tragfähigkeit, sondern an ihrem Gegenstand. Sie handelt nämlich nicht nur - wie Hunderte andere wissenschaftliche Theorien - von der "Welt da draußen“, sondern vor allem auch von uns selbst und von unserem Platz in dieser Welt. Den einen gilt sie obendrein als Überwinderin religiösen Aberglaubens, den anderen als neuer Zugang zu Gott und seinem Wirken in der Welt. Ferner sehen die einen in der Evolution eine unbezweifelbare Tatsache gleich der Schwerkraft oder dem Holocaust, die anderen aber eine - noch oder dauerhaft - unbewiesene Hypothese oder gar eine falsche Schöpfungslehre. Und während die meisten Streitfragen solcher Art nach wechselseitig akzeptierten Regeln ‚normaler Wissenschaft‘ geklärt werden, wird bei der Frage nach dem Woher unserer Spezies und Kultur die intellektuelle Zuständigkeit von Wissenschaft mitunter überhaupt bezweifelt. Anscheinend geht es schon um recht tiefe Schichten unserer Kultur und nicht nur der wissenschaftlichen, wenn - wie seit 150 Jahren - um die Evolutionstheorie gestritten wird. Wie sehen diese Schichten aus?

The Use of Actigraphy to Study Sleep Disorders in Preschoolers: Some Concerns about Detection of Nighttime Awakenings

PubMed Central

Sitnick, Stephanie L.; Goodlin-Jones, Beth L.; Anders, Thomas F.

2008-01-01

Study Objectives: This study compared actigraphy with videosomnography in preschool-aged children, with special emphasis on the accuracy of detection of nighttime awakenings. Design: Fifty-eight participants wore an actigraph for 1 week and were videotaped for 2 nights while wearing the actigraph. Setting: Participants were solitary sleepers, studied in their homes. Participants: One group (n = 22) was diagnosed with autism, another group (n = 11) had developmental delays without autism, and a third group (n = 25) were typically developing children; age ranged from 28 to 73 months (mean age 47 months); 29 boys and 29 girls. Interventions: N/A. Measurements and Results: Nocturnal sleep and wakefulness were scored from simultaneously recorded videosomnography and actigraphy. The accuracy of actigraphy was examined in an epoch-by-epoch comparison with videosomnography. Findings were 94% overall agreement, 97% sensitivity, and 24% specificity. Statistical corrections for overall agreement and specificity resulted in an 89% weighted-agreement and 27% adjusted specificity. Conclusions: Actigraphy has poor agreement for detecting nocturnal awakenings, compared with video observations, in preschool-aged children. Citation: Sitnick SL; Goodlin-Jones BL; Anders TF. The use of actigraphy to study sleep disorders in preschoolers: some concerns about detection of nighttime awakenings. SLEEP 2008;31(3):395-401. PMID:18363316

Feasibility of Iodine and Bromine analysis in Genesis AloS collectors

NASA Astrophysics Data System (ADS)

Pravdivtseva, O.; Meshik, A.; Hohenberg, C. M.; Burnett, D. S.

2011-12-01

Comparison of solar, meteoritic and terrestrial elemental abundances provides understanding of the formation and evolution of the solar system. Yet, the majority of the solar abundances are based on meteoritic values [1-6]. As a continuation of our noble gas measurements of the Solar Wind (SW) [7] we attempted to evaluate the possibility of SW-iodine and SW-bromine analyses in the Genesis Solar Wind Aluminum on Sapphire collectors (AloS) using the conversions: 127I(n,γβ)128Xe, 79Br(n,γβ)80Kr and 81Br(n,γβ)82Kr. To estimate the extent of terrestrial halogen contamination in Genesis collectors, several flown fragments of AloS were submerged in methanol (for 1 hour and for 48 hours), rinsed, dried, sealed under vacuum in fused quartz ampoules and irradiated at the Missouri University Research Reactor receiving fluence ˜ 2E+19 thermal neutrons/cm2. Single step laser extraction using 1064 nm laser ablation of 0.7 cm2 area demonstrated clear signature of solar wind as indicated by 129Xe/132Xe = 1.045 ± 0.005, while 128Xe/132Xe = 1.01 ± 0.03 had a 12-fold excess compared to the solar value. Longer washing apparently reduces iodine contamination 4 times, implying that it is surface correlated. Krypton analysis showed 17% excess in 82Kr and 3-fold excess in 80Kr in agreement with their production ratio. A longer 48-hour washing reduced Br contamination 50 times. In order to better separate SW halogens from ubiquitous terrestrial contamination we employed a depth-profiling of AloS using 266 nm laser ablation. Laser beam power was increased in 12 consecutive steps using a combination of controlled defocusing and attenuation by a polarizing beamsplitter. Depth profile analysis revealed that terrestrial halogen contamination is present at the surface and at the interface between Al and sapphire substrate and is more pronounced for iodine, as indicated by 128Xe/132Xe ratio that is higher than atmospheric and solar wind values in all 12 rasters. While washing procedure reduced surface contamination, it did not affect iodine and bromine associated with the interface. Thus, cleaner Si-based Genesis collectors could be more suitable for SW halogen analyses. Our first results suggest that determination of solar iodine and bromine is potentially feasible, considering the possibility of analyzing larger collector areas irradiated with higher neutron fluence in order to improve counting statistics of the measurements. Supported by NASA grant NNX07AM76G. [1] Anders E. and Ebihara M. 1982. GCA 46:2363-2380. [2] Anders E. and Grevesse N. 1989. GCA 53:197-214. [3] Cameron A. G. W. 1968. in Origin and distribution of the elements (Ahrens L. H., ed.), Pergamon, Oxford:125-143. [4] Cameron A. G. W. 1973. Space Science Revues 15:121-146. [5] Suess H. E. and Urey H. C. 1956. Revisions of Modern Physics 28:53-74. [6] Lodders K. 2010. in: Principles and Perspectives in Cosmochemistry. 379-417. [7] Meshik A. et all. 2011. 74th Meteoritical Society Meeting, Abstract#5471.

Virtuelle Kraftwerke für Smart Markets

NASA Astrophysics Data System (ADS)

Dürr, Thomas; Heyne, Jean-Christoph

In den zurückliegenden Jahren haben insbesondere zwei Trends die Stromversorgung bestimmt: der starke Anstieg der dezentralen und der Ausbau der regenerativen Stromerzeugung, die vor allem in den Verteilnetzen stattfinden. Angesichts dieser Entwicklung gewinnen virtuelle Kraftwerke (VK) immer mehr an Bedeutung. In der frühen Phase waren VK insbesondere eine Möglichkeit, kleine dezentrale Erzeuger zu einer größeren Einheit zu bündeln und sie so marktfähig zu machen. Heute werden sie - überwacht und gesteuert über ein Dezentrales Energie-Management-System (DEMS) - gemeinsam mit Demand Response betrieben, also dem Reagieren eines Energieabnehmers auf Marktpreise. Das Demand Side Management soll zur Flexibilisierung der Industrie beitragen. Da der Ausbau der Übertragungsnetze nur schleppend vorankommt, kann die Nutzung von lastseitiger Flexibilität einen wichtigen Beitrag zur Versorgungssicherheit leisten. Im zweiten Teil des Beitrags geht es um die Entwicklung der Märkte. Großes Interesse besteht immer noch an der Regelenergie, zumal der Bedarf bis 2050 deutlich steigen wird. Die Spotmärkte Intraday und Day-Ahead wachsen kontinuierlich, deshalb werden sie für VK immer wichtiger. Am Ende gibt der Beitrag einen Ausblick auf die künftige Entwicklung, in der Regelenergie- und Spotmärkte noch eine Rolle spielen, aber andere Geschäftsmodelle wichtiger werden. Darüber hinaus geht es um langfristige Entwicklungen, die z. B. zusätzliche Serviceleistungen durch VK betreffen.

Slow-binding inhibition of carboxylesterase and other serine hydrolases by chlorodifluoroacetaldehyde.

PubMed

Yin, H; Jones, J P; Anders, M W

1993-01-01

The chlorofluorocarbon substitute 1,2-dichloro-1,1-difluoroethane (HCFC-132b) undergoes oxidative metabolism in rats to give a range of metabolites, including chlorodifluoroacetaldehyde [Harris and Anders (1991) Chem. Res. Toxicol. 4, 180]. The present experiments were undertaken after studies to characterize an unidentified metabolite of HCFC-132b revealed that chlorodifluoroacetaldehyde was toxic in vivo: rats given chlorodifluoroacetaldehyde died showing signs of cholinergic stimulation. Because some fluoroketones are known inhibitors of hydrolases, including acetylcholinesterase, the inhibitory effects of chlorodifluoroacetaldehyde on acetylcholinesterase (electric eel and human erythrocyte), on pseudocholinesterase (horse serum), on carboxylesterase (pig liver), and on alpha-chymotrypsin (bovine pancreas) were studied. In aqueous solution, the ratio chlorodifluoroacetaldehyde:chlorodifluroacetaldehyde hydrate, as determined by 1H nuclear magnetic resonance spectroscopy, was 1:157. Chlorodifluoroacetaldehyde was a slow-binding inhibitor of both acetylcholinesterases, of pseudocholinesterase, and of carboxylesterase; the Ki values, corrected for the aldehyde:hydrate ratio, were 150 nM, 1.7 nM, 3.7 nM, and 23 pM, respectively, as determined by final velocity of the progress curves; the kon values were 9.1 x 10(4), 1.1 x 10(5), 3.2 x 10(4), and 9.2 x 10(5) M-1 min-1, respectively. Chlorodifluoroacetaldehyde did not inhibit alpha-chymotrypsin. Acetaldehyde and trichloroacetaldehyde were classical competitive inhibitors of acetylcholinesterase. These results show that hydrochlorofluorocarbon metabolites may exert significant biological effects.

Update zum klinischen Einsatz von Inhibitoren mutierter Phosphokinasen beim Melanom.

PubMed

Cosgarea, Ioana; Ritter, Cathrin; Becker, Jürgen C; Schadendorf, Dirk; Ugurel, Selma

2017-09-01

Die Behandlungsstrategie beim metastasierten Melanom hat sich mit der Identifizierung therapeutisch angreifbarer molekularer Zielstrukturen innerhalb zellulärer Signalwege radikal geändert. Durch die Zulassung von Substanzen, die gezielt an den zentralen Schaltmolekülen, den Phosphokinasen, angreifen, können diese Signalwege selektiv abgeschaltet werden. Dies ist insbesondere bei denjenigen Tumoren von Interesse, deren Signalwege durch aktivierende Mutationen der für die Schaltmoleküle kodierenden Gene konstitutiv aktiviert sind. Aktuell ist diese therapeutische Strategie insbesondere für Patienten bedeutsam, deren Melanome eine Mutation im BRAF-Gen aufweisen. Diese Patienten können durch eine Kombinationstherapie aus Inhibitoren der Phosphokinasen BRAF und MEK langfristig mit sehr guter Krankheitskontrolle behandelt werden. Unter dieser Kombinationstherapie wird aktuell ein progressionsfreies Überleben von über zehn Monaten und ein Gesamtüberleben von mehr als zwei Jahren bei guter Lebensqualität erzielt. Da unter längerfristiger Therapie mit Kinaseinhibitoren jedoch bei einem Großteil der Patienten eine Resistenzbildung auftritt, sind aktuelle klinische Therapiestudien auf die Suche nach geeigneten Kombinationspartnern unter Blockierung anderer Signalwege oder unter Aktivierung der T-Zell-vermittelten Immunantwort ausgerichtet. Der vorliegende Übersichtsartikel stellt sowohl die aktuell verfügbaren als auch die in der klinischen Testung befindlichen zukünftigen Optionen der zielgerichteten Therapie des Melanoms dar. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Hawking's A Briefer History of Time's No-God-Universe disproven by primordial ^218Po halos embedded in granite rocks, which proves their rapid creation due to ^218Po's 3 min t1/2, something only the God of Genesis could have done

NASA Astrophysics Data System (ADS)

Gentry, Robert

2011-04-01

Quotes from my Science (184, 62, 1974) report, Radiohalos in Radiochronological and Cosmological Perspective, show why primordial polonium halos earlier commanded attention for creation," It is also apparent that Po halos do pose contradictions to currently held views of Earth history" "For example, there is first the problem of how isotopic separation of several Po isotopes [or their β-decay precursors could have occurred naturally. Second, a straightforward explanation of ^218Po halos implies that the 1-μm radiocenters of very dark halos of this type initially contained as many as 5 x 10^9 atoms (a concentration of more than 50 percent) of the isotope ^218Po (half-life, 3 minutes), a problem that almost defies reason. A further necessary consequence, that such Po halos could have formed only if the host rocks underwent a rapid crystallization, renders exceedingly difficult, in my estimation, the prospect of explaining these halos by physical laws as presently understood." In 1977 E. P. Wigner, G. N. Flerov (Dubna), Ed Anders, E. Segre, F. Dyson, and John Wheeler all commented on these results (see alphacosmos.net). Also, ^14N detection in dwarf radiohalos may be of cosmological significance in implying a superheavy element origin from ^14C emission.

An assessment of the micrometeoritic component in the Martian soil

NASA Technical Reports Server (NTRS)

Flynn, George J.

1989-01-01

Particles in the mass range from 10 to the minus 7th power to 10 to the minus 3rd power grams contribute 80 percent of the total mass influx of meteoritic material in the 10 to the minus 13th power to 10 to the 6th power gram mass range at Earth (Hughes, 1978). On Earth atmospheric entry, all but the smallest particles in the 10 to the minus 7th power to 10 to the minus 3rd power gram mass range, about 60 to 1200 micrometers in diameter, are heated sufficiently to melt and vaporize. Mars, because of its lower escape velocity and larger atmospheric scale height, is a much more favorable site for unmelted survival of micrometeorites on atmospheric deceleration. Researchers calculate that a significant fraction of particles throughout the 60 to 1200 micrometer diameter range will survive atmospheric entry unmelted. Thus returned Mars soils may offer a resource for sampling micrometeorites in a size range uncollectable in unaltered form at Earth. The addition of meteoritic material to the Mars soils should perturb their chemical composition, as has been detected using the soils on the Moon (Anders, et al., 1973). Using measured mass influx at Earth and estimates of the Mars/Earth flux ratio, researchers estimate a mass influx at Mars of between 2,700 and 202,000 metric tons per year.

Ant colony optimization and event-based dynamic task scheduling and staffing for software projects

NASA Astrophysics Data System (ADS)

Ellappan, Vijayan; Ashwini, J.

2017-11-01

In programming change organizations from medium to inconceivable scale broadens, the issue of wander orchestrating is amazingly unusual and testing undertaking despite considering it a manual system. Programming wander-organizing requirements to deal with the issue of undertaking arranging and in addition the issue of human resource portion (also called staffing) in light of the way that most of the advantages in programming ventures are individuals. We propose a machine learning approach with finds respond in due order regarding booking by taking in the present arranging courses of action and an event based scheduler revives the endeavour arranging system moulded by the learning computation in perspective of the conformity in event like the begin with the Ander, the instant at what time possessions be free starting to ended errands, and the time when delegates stick together otherwise depart the wander inside the item change plan. The route toward invigorating the timetable structure by the even based scheduler makes the arranging method dynamic. It uses structure components to exhibit the interrelated surges of endeavours, slip-ups and singular all through different progression organizes and is adjusted to mechanical data. It increases past programming wander movement ask about by taking a gander at a survey based process with a one of a kind model, organizing it with the data based system for peril assessment and cost estimation, and using a choice showing stage.

Dopamine and the Biology of Creativity: Lessons from Parkinson’s Disease

PubMed Central

Lhommée, Eugénie; Batir, Alina; Quesada, Jean-Louis; Ardouin, Claire; Fraix, Valérie; Seigneuret, Eric; Chabardès, Stéphan; Benabid, Alim-Louis; Pollak, Pierre; Krack, Paul

2014-01-01

Background: Parkinson’s disease (PD) is characterized by reduced flexibility, conceptualization, and visuo-spatial abilities. Although these are essential to creativity, case studies show emergence of creativity during PD. Knowledge about the role of dopamine in creativity so far only stems from a few case reports. We aim at demonstrating that creativity can be induced by dopaminergic treatments in PD, and tends to disappear after withdrawal of dopamine agonists. Methods: Eleven consecutive creative PD patients were selected from candidates for subthalamic nucleus deep brain stimulation (STN DBS) surgery, and compared to 22 non-creative control PD patients. Motor disability (UPDRS III), cognition (Frontal score, Mattis scale), and behavior (Ardouin scale) were assessed before surgery and 1 year after. Results: Before surgery, whereas cognitive and motor assessments were similar between groups, dopamine agonist (but not levodopa) dosages were higher in creative patients (p = 0.01). The Ardouin scale revealed also a specific psycho-behavioral profile of creative patients which had higher scores for mania (p < 0.001), hobbyism (p = 0.001), nocturnal hyperactivity (p = 0.041), appetitive functioning (p = 0.003), and ON euphoria (p = 0.007) and lower scores for apathy and OFF dysphoria (p = 0.04 for each). Post-operative motor, cognitive, and behavioral scores as dopaminergic treatment dosages were equivalent between groups. Motor improvement allowed for a 68.6% decrease in dopaminergic treatment. Only 1 of the 11 patients remained creative after surgery. Reduction of dopamine agonist was significantly correlated to the decrease in creativity in the whole population of study (Spearman correlation coefficient ρ = 0.47 with confidence index of 95% = 0.16; 0.70, p = 0.0053). Conclusion: Creativity in PD is linked to dopamine agonist therapy, and tends to disappear after STN DBS in parallel to reduction of dopamine agonists, which are relatively selective for the mesolimbic D3 dopamine receptors. PMID:24795692

Parkinson's disease-cognitive rating scale: psychometrics for mild cognitive impairment.

PubMed

Fernández de Bobadilla, Ramón; Pagonabarraga, Javier; Martínez-Horta, Saül; Pascual-Sedano, Berta; Campolongo, Antonia; Kulisevsky, Jaime

2013-09-01

Lack of validated data on cutoff scores for mild cognitive impairment (MCI) and sensitivity to change in predementia stages of Parkinson's disease (PD) limit the utility of instruments measuring global cognition as screening and outcome measures in therapeutic trials. Investigators who were blinded to PD-Cognitive Rating Scale (PD-CRS) scores classified a cohort of prospectively recruited, nondemented patients into a PD with normal cognition (PD-NC) group and a PD with MCI (PD-MCI) group using Clinical Dementia Rating (CDR) and the Mattis Dementia Rating Scale-2 (MDRS-2). The discriminative power of the PD-CRS for PD-MCI was examined in a representative sample of 234 patients (145 in the PD-NC group; 89 in the PD-MCI group) and in a control group of 98 healthy individuals. Sensitivity to change in the PD-CRS score (the minimal clinically important difference was examined with the Clinical Global Impression of Change scale and was calculated with a combination of distribution-based and anchor-based approaches) was explored in a 6-month observational multicenter trial involving a subset of 120 patients (PD-NC, 63; PD-MCI, 57). Regression analysis demonstrated that PD-CRS total scores (P < 0.001) and age (P = 0.01) independently differentiated PD-NC from PD-MCI. Area under the receiver operating characteristic curve (AUC) analysis (AUC, 0.85; 95% confidence interval, 0.80-0.90) indicated that a score ≤ 81 of 134 was the optimal cutoff point on the total score for the PD-CRS (sensitivity, 79%; specificity, 80%; positive predictive value, 59%; negative predictive value, 91%). A range of change from 10 to 13 points on the PD-CRS total score was indicative of clinically significant change. These findings suggest that the PD-CRS is a useful tool to identify PD-MCI and to track cognitive changes in nondemented patients with PD. © 2013 International Parkinson and Movement Disorder Society.

Executive cognitive tests for the evaluation of patients with Parkinson’s disease

PubMed Central

Sobreira, Emmanuelle Silva Tavares; Pena, Marina Ceres Silva; Silva Filho, José Humberto; Souza, Carolina Pinto; Oliveira, Guiomar Nascimento; Tumas, Vitor; do Vale, Francisco de Assis Carvalho

2008-01-01

Parkinson’s disease (PD) is characterized by changes in movement, which are later followed by cognitive, behavioral and psychological changes. The objective of the present study was to correlate different tests used to examine executive functions in PD patients followed at a specialized outpatient clinic. Methods Thirty-five patients with idiopathic PD aged 63.0 years on average and with mean schooling of 5.5±4.2 years, were examined using the following tests: Mattis Dementia Rating Scale (MDRS), Scales for Outcomes of Parkinson’s Disease-Cognition (SCOPA-COG), Wisconsin Card Sorting Test (WCST), Frontal Assessment Battery (FAB), Digit Span – Inverse Order (IO) (a subtest of the WAIS III) and Verbal Fluency Test (category animals). Results Significant correlations were detected between FAB and MDRS Conceptualization (0.814), MDRS Initiation/Perseveration (I/P) and SCOPA-COG Executive Function (0.643), FAB and MDRS I/P (0.601), FAB and Verbal Fluency (0.602), MDRS I/P and MDRS Conceptualization (0.558), Verbal Fluency and MDRS I/P (0.529), MDRS Attention and SCOPA-COG Executive Function (0.495), MDRS Conceptualization and SCOPA-COG Executive Function (0.520), FAB and Digit Span (OI) (0.503), Verbal Fluency and MDRS Conceptualization (0.501), and WCST perseverative errors and FAB (–0.379), WCST perseverative errors and MDRS Conceptualization (0.445), WCST perseverative errors and MDRS I/P (–0.407) and WCST categories completed and MDRS Conceptualization (0.382). Discussion The results demonstrated strong correlations between most of the tests applied, but no associations were detected between the WCST and the other tests, a fact that may be explained by the heterogeneity of scores obtained in the tests by the patients evaluated. A difficulty of the present study was the lack of a control groups for the establishment of adequate standards for this population. PMID:29213572

Long-term impact of subthalamic stimulation on cognitive function in patients with advanced Parkinson's disease.

PubMed

Acera, M; Molano, A; Tijero, B; Bilbao, G; Lambarri, I; Villoria, R; Somme, J; Ruiz de Gopegui, E; Gabilondo, I; Gomez-Esteban, J C

2017-07-13

The aim of this study was to evaluate the effects of deep brain stimulation of the subthalamic nucleus (DBS-SN) on cognitive function in patients with Parkinson's disease (PD) 5 years after surgery. We conducted a prospective study including 50 patients with PD who underwent DBS-SN (62.5% were men; mean age of 62.2±8.2 years; mean progression time of 14.1±6.3 years). All patients were assessed before the procedure and at one year after surgery; 40 patients were further followed up until the 5-year mark. Follow-up assessments included the following neuropsychological tests: Mini-Mental State Examination (MMSE), Mattis Dementia Rating Scale (MDRS), letter-number sequencing of the WAIS-III (WAIS-III-LN), clock-drawing test, Rey auditory verbal learning test (RAVLT), Benton Visual Retention Test (BVRT), Judgment of Line Orientation (JLO) test, FAS Phonemic Verbal Fluency Test, Stroop test, and the Montgomery-Asberg Depression Rating Scale (MADRS). Patients were found to score lower on the MMSE (-0.89%), clock-drawing test (-2.61%), MDRS (-1.72%), and especially phonemic (-13.28%) and sematic verbal fluency tests (-12.40%) at one year after surgery. Delayed recall on the RAVLT worsened one year after the procedure (-10.12%). At 5 years, impairment affected mainly verbal fluency; scores decreased an additional 16.10% and 16.60% in semantic and phonemic verbal fluency, respectively. Moderate decreases were observed in immediate recall (-16.87%), WAIS-III-LN (-16.67%), and JLO test (-11.56%). In our sample, DBS-SN did not result in global cognitive impairment 5 years after surgery. Verbal function was found to be significantly impaired one year after the procedure. Impaired learning and visuospatial function may be attributed to degeneration associated with PD. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Reconnaissance stratigraphy of the Red Glacier Formation (Middle Jurassic) near Hungryman Creek, Cook Inlet basin, Alaska

USGS Publications Warehouse

LePain, D.L.; Stanley, Richard G.; Helmold, K.P.

2016-01-01

Geochemical data suggest the source of oil in upper Cook Inlet fields is Middle Jurassic organic-rich shales in the Tuxedni Group (Magoon and Anders, 1992; Lillis and Stanley, 2011; LePain and others, 2012, 2013). Of the six formations in the group (Detterman, 1963), the basal Red Glacier Formation is the only unit that includes fine-grained rocks in outcrop that appear to be organic-rich (fig. 3-1). In an effort to better understand the stratigraphy and source-rock potential of the Red Glacier Formation, the Alaska Division of Geological & Geophysical Surveys, in collaboration with the Alaska Division of Oil and Gas and the U.S. Geological Survey, has been investigating the unit in outcrop between Tuxedni Bay and the type section at Lateral and Red glaciers (Stanley and others, 2013; LePain and Stanley, 2015; Helmold and others, 2016 [this volume]). Fieldwork in 2015 focused on a southeast-trending ridge south of Hungryman Creek, where the lower 60–70 percent of the formation (400–500 m) is exposed and accessible, except for the near-vertical faces of three segments near the southeast end of the ridge (figs. 3-2 and 3-3). Three stratigraphic sections were measured along the ridge to document facies and depositional environments (figs. 3-3 and 3-4). Steep terrain precluded study of the upper part of the formation exposed east of the ridge. This report includes a preliminary summary of findings from the 2015 field season.

Historical background of bone conduction hearing devices and bone conduction hearing aids.

PubMed

Mudry, Albert; Tjellström, Anders

2011-01-01

During the last 20 years, bone-anchored hearing aids (Baha(®)) became a familiar solution in the treatment of some types of hearing loss. The aim of this chapter is to present the different historical steps which have permitted the production of this new bone conduction hearing device. The recognition of bone conduction hearing is old and was known at least in Antiquity. During the Renaissance, Girolamo Cardano demonstrated a method by which sound may be transmitted to the ear by means of a rod or the shaft of a spear held between one's teeth: this was the beginning of teeth stimulators to improve hearing, firstly in connection with a musical instrument and then, in the second part of the 19th century, with the speaker. The development of the carbon microphone at the beginning of the 20th century allowed the construction of the bone conduction vibrator placed on the mastoid area, notably supported by eyeglasses since the 1950s. Confronted by various problems, and notably the loss of part of sound in the soft tissue of the external mastoid, the idea to implant the vibrator into the mastoid bone was developed in Göteborg, and the first Baha was implanted in 1977 by Anders Tjellström. From that date, various improvements allowed the development of the actual Baha. These different steps are presented in this study, supported by original documentation. Copyright © 2011 S. Karger AG, Basel.

Spitznävi: unterschiedliche klinische, dermatoskopische und histopathologische Merkmale in der Kindheit.

PubMed

Dika, Emi; Neri, Iria; Fanti, Pier Alessandro; Barisani, Alessia; Ravaioli, Giulia Maria; Patrizi, Annalisa

2017-01-01

Die Charakterisierung der klinischen Merkmale und des biologischen Potenzials von Spitznävi hat in den letzten Jahrzehnten breites Interesse gefunden. Das Ziel dieser Arbeit ist die Beschreibung der klinischen und dermatoskopischen Merkmale von Spitznävi sowie des klinischen Ergebnisses nach chirurgischer Exzision von Spitznävi in drei pädiatrischen Altersgruppen. Restrospektive Studie zur Analyse von klinischen Merkmalen, videodermatoskopischen Bildern, histopathologischen Diagnosen und Behandlungsergebnissen. Der Grad der Pigmentierung wurde sowohl klinisch als auch histopathologisch beurteilt. Bei 71 Patienten wurden 72 spitzoide Neoplasien entfernt. Videodermatologische Bilder lagen für 41 Patienten vor. Das Muster der Pigmentierung korrelierte signifikant mit dem Alter der Patienten: Hyperpigmentierte Läsionen waren bei Vorschulkindern selten, bei Patienten von 7 bis 12 Jahren und ab 13 Jahren dagegen häufiger. Eine histopathologische Diagnose von atypischen Spitznävi wurde selten durchgeführt. Keiner der Patienten, bei denen ursprünglich ein atypischer Spitznävus diagnostiziert worden war, entwickelte ein Lokalrezidiv oder Metastasen während der anschließenden Nachbeobachtung. Pigmentierte Spitznävi traten im Alter ab 13 Jahren häufiger auf. Die Studie bestätigt andere Berichte über die Altersverteilung von Pigmentierungsmustern und hebt die geringe Anzahl atypischer Spitznävi bei pädiatrischen Patienten hervor sowie das Ausbleiben von Rezidiven bei der langfristigen Nachbeobachtung. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Pollen mitosis and pollen tube growth inhibition by SO/sub 2/ in cultured pollen tubes of Tradescantia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, T.H.; Khan, S.H.

Mature pollen of Tradescantia paludosa Anders, Sax clone-3 was collected from greenhouse grown plants and desiccated in the dark for 4--5 hours. The pollen was sown on microslides coated with lactose agar medium (supplemented with 0.02 percent colchicine). Five minutes after sowing, pollen cultures were treated with various concentrations (0.075--2000 ppM) of SO/sub 2/ obtained from the chemical reaction between K/sub 2/S/sub 2/O/sub 5/ and HCl. Treatments were carried out in an airtight Plexiglas chamber throughout the full incubation period of 19 hours. Treated and control pollen cultures were fixed and stained in aceto-carmine or Feulgen reaction to determine themore » tube lengths and mitotic indices. Results of repeated experiments indicated that the values of mitotic indices dropped from the normal 38.7 percent in the control to the range of 24.3--3.8 percent when treated with 0.075--50.00 ppM of SO/sub 2/. Pollen tube growth was inhibited from the normal length of 1.5 mm in the control to the range of 800--100 ..mu..m when treated with 10--2000 ppM of SO/sub 2/. The inhibitory effect of SO/sub 2/ presumably resulted from physiological disturbance of the cell and severe damage to chromosomes of both generative and tube nuclei of the pollen tubes.« less

Antimicrobial and brine shrimp toxicity of some plants used in traditional medicine in Bukoba District, north-western Tanzania.

PubMed

Moshi, M J; Innocent, E; Masimba, P J; Otieno, D F; Weisheit, A; Mbabazi, P; Lynes, M; Meachem, K; Hamilton, A; Urassa, I

2009-01-01

Herbal medicines constitute a potentially important resource for new and safe drugs for the management of microbial infections and other diseases. In this study, dichloromethane, ethylacetate and ethanol extracts of Canarium schweinfurthii Engl., Dissotis brazzae Cong., Iboza urticifolia (Bak) E.A.Bruce, Isoglosa lacteal Lindau, Strombosia Scheffleri Engl., and Whitfieldia elongate T. Anders were tested for antimicrobial activity and brine shrimp toxicity. The objective was to validate claims that they are used to treat bacterial infections, diarrhoea and heal wounds among the Haya tribe of north-western Tanzania. At least one extract of each plant showed antibacterial activity. Dichloromethane extracts were the most active while ethanol extracts were the least active. Extracts of Whitfieldia elongate and Isoglossa lacteal were the most and least active with MICs in the range 0.08-0.62 mg/ml and 15.6-62.5 mg/ml, respectively. The dichloromethane extract of Whitfieldia elongate exhibited strong antifungal activity against Cryptococcus neoformans. Against brine shrimp larvae, the extracts from the six plants exhibited a low to very low toxicity with LC50 values ranging from 15.35-374.0 microg/ml. However, ethanol extracts of Dissotis brazzae and Strombosia scheffleri had LC50 values of >1000 microg/ml. The seemingly innocuous nature and relatively good antibacterial activity against skin infections and gastrointestinal pathogenic bacteria support the traditional uses of the plants and deserve more detailed studies.

Xe incorporation in crust and upper mantle minerals: new experimental and theoretical evidences

NASA Astrophysics Data System (ADS)

Celine, C.; Sanloup, C.; Blanchard, M.; Lazzeri, M.; Balan, E.; Hudspeth, J.

2017-12-01

Storage of Xe in silicate minerals has been proposed to explain the `Missing Xenon' issue, i.e. the low Xe abundance in the Earth's and Mars' atmospheres compared to other noble gases [1]. However, data about Xe incorporation in minerals remain scarce due to high Xe volatility preventing studies at ambient conditions. Xe incorporations in olivine [2] and quartz [3] have been proposed based on experimental evidences at high pressures and temperatures. Nevertheless, Xe incorporation mechanisms remained so far only hypothetical. We present here new in situ X-ray diffraction data in diamond-anvil cell showing Xe incorporation in widespread silicate minerals of the continental crust (feldspars and quartz) and of the upper mantle (olivine) at relevant pressure and temperature conditions. Significant variations in cell parameters are retrieved in Xe-rich minerals as well as new peaks, implying change in the crystal structures linked to Xe incorporation. Theoretical calculations have been performed (using the density functional theory) to propose Xe incorporation sites able to reproduce experimental observations. In olivine, a Xe for Si substitutions is proposed, with up to 0.4 at% Xe potentially stored in olivine at depth. These new constraints on Xe incorporation at depths in silicate minerals, often neglected, could be crucial in the `Missing Xenon' issue. [1] Anders and Owen (1977) Science 198, 453-465, [2] Sanloup et al. (2011) Geochim. Cosmochim. Acta 75, 6271-6284, [3] Sanloup et al., (2005) Science, 310, 1174-1177

Oral Histories in Meteoritics and Planetary Science - XV: John Wood

NASA Astrophysics Data System (ADS)

Sears, Derek W. G.

2012-05-01

John Wood (Fig. 1) was trained in Geology at Virginia Tech and M.I.T. To fulfill a minor subject requirement at M.I.T., he studied astronomy at Harvard, taking courses with Fred Whipple and others. Disappointed at how little was known in the 1950s about the origin of the earth, he seized an opportunity to study a set of thin sections of stony meteorites, on the understanding that these might shed light on the topic. This study became his Ph.D. thesis. He recognized that chondrites form a metamorphic sequence, and that idea proved surprisingly hard to sell. After brief service in the Army and a year at Cambridge University, John served for 3 years as a research associate with Ed Anders at the University of Chicago. He then returned to the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, where he spent the remainder of his career. At Chicago, he investigated the formation of the Widmanstätten structure, and found that the process informs us of the cooling rates of iron meteorites. Back in Cambridge, he collaborated with W. R. Van Schmus on a chondrite classification that incorporates metamorphic grade, and published on metal grains in chondrites, before becoming absorbed by preparations for the return of lunar samples by the Apollo astronauts. His group's work on Apollo samples helped to establish the character of the lunar crust, and the need for a magma ocean to form it. Wood served as President of the Meteoritical Society in 1971-72 and received the Leonard Medal in 1978.

Reconnaissance studies of potential petroleum source rocks in the Middle Jurassic Tuxedni Group near Red Glacier, eastern slope of Iliamna Volcano

USGS Publications Warehouse

Stanley, Richard G.; Herriott, Trystan M.; LePain, David L.; Helmold, Kenneth P.; Peterson, C. Shaun

2013-01-01

Previous geological and organic geochemical studies have concluded that organic-rich marine shale in the Middle Jurassic Tuxedni Group is the principal source rock of oil and associated gas in Cook Inlet (Magoon and Anders, 1992; Magoon, 1994; Lillis and Stanley, 2011; LePain and others, 2012; LePain and others, submitted). During May 2009 helicopter-assisted field studies, 19 samples of dark-colored, fine-grained rocks were collected from exposures of the Red Glacier Formation of the Tuxedni Group near Red Glacier, about 70 km west of Ninilchik on the eastern flank of Iliamna Volcano (figs. 1 and 3). The rock samples were submitted to a commercial laboratory for analysis by Rock-Eval pyrolysis and to the U.S. Geological Survey organic geochemical laboratory in Denver, Colorado, for analysis of vitrinite reflectance. The results show that values of vitrinite reflectance (percent Ro) in our samples average about 2 percent, much higher than the oil window range of 0.6–1.3 percent (Johnsson and others, 1993). The high vitrinite reflectance values indicate that the rock samples experienced significant heating and furthermore suggest that these rocks may have generated oil and gas in the past but no longer have any hydrocarbon source potential. The high thermal maturity of the rock samples may have resulted from (1) the thermaleffects of igneous activity (including intrusion by igneous rocks), (2) deep burial beneath Jurassic, Cretaceous, and Tertiary strata that were subsequently removed by uplift and erosion, or (3) the combined effects of igneous activity and burial.

Little Chondrules and Giant Impacts

NASA Astrophysics Data System (ADS)

Taylor, G. J.

2005-10-01

Alexander (Sasha) Krot (University of Hawaii), Yuri Amelin (University of Toronto), Pat Cassen (SETI Institute), and Anders Meibom (Museum National d'Histoire Naturelle, Paris) studied and then extracted frozen droplets of molten silicate (chondrules) from unusual meteorites rich in metallic iron-nickel. Called CB (Bencubbin-like) chondrites, these rare but fascinating meteorites contain chondrules with different properties than those in other types of chondrites. Most notably, the chondrules contain very small concentrations of volatile elements and variable concentrations of refractory elements. (Volatile elements condense from a gas at a relatively low temperature, or are boiled out of solids or liquids at relatively low temperature. Refractory elements are the opposite.) Some of the metal grains in CB chondrites are chemically zoned, indicating that they formed by condensation in a vapor cloud. The most intriguing feature of chondrules in CB chondrites is their relatively young age. Lead-lead isotopic dating of chondrules separated from two CB chondrites show that they formed 5 million years after formation of the first solids in the solar system (calcium-aluminum-rich inclusions), which is about at least two million years after formation of other chondrules, and after energetic events in the solar nebula stopped. Krot and his colleagues suggest that the CB chondrules formed as the result of an impact between Moon- to Mars-sized protoplanets. Such impacts were so energetic that huge amounts of material were vaporized and then condensed as chondrules or chemically zoned metal grains. This event enriched refractory elements and depleted volatile elements. Such large impacts appear to play important roles in planet formation, including the formation of the Moon.

Efficacy and safety of Ginkgo biloba standardized extract in the treatment of vascular cognitive impairment: a randomized, double-blind, placebo-controlled clinical trial

PubMed Central

Demarin, Vida; Bašić Kes, Vanja; Trkanjec, Zlatko; Budišić, Mislav; Bošnjak Pašić, Marija; Črnac, Petra; Budinčević, Hrvoje

2017-01-01

Objectives The aim of this randomized, double-blind, placebo-controlled trial was to determine the efficacy and safety of Ginkgo biloba extract in patients diagnosed with vascular cognitive impairment (VCI). Methods A total of 90 patients (aged 67.1±8.0 years; 59 women) were randomly allocated (1:1:1) to receive G. biloba 120 mg, G. biloba 60 mg, or placebo during a 6-month period. Assessment was made for efficacy indicators, including neuropsychological tests scores (Sandoz Clinical Assessment Geriatric Scale, Folstein Mini-Mental State Examination, Mattis Dementia Rating Scale, and Clinical Global Impression) and transcranial Doppler ultrasound findings. Safety indicators included laboratory findings, reported adverse reactions, and clinical examination. Results At the end of 6-month study period, G. biloba 120 and 60 mg showed a statistically significant positive effect in comparison with placebo only on the Clinical Global Impression score (2.6±0.8 vs 3.1±0.7 vs 2.8±0.7, respectively; P=0.038). The Clinical Global Impression score showed a significant deterioration from the baseline values in the placebo group (−0.3±0.5; P=0.021) as opposed to G. biloba groups. No significant differences were found in the transcranial Doppler ultrasound findings. Adverse reactions were significantly more common and serious in the placebo group (16 subjects) than in either of the two G. biloba extract groups (eight and nine subjects, respectively), whereas laboratory findings and clinical examinations revealed no differences between the groups receiving G. biloba extract and placebo. Conclusion According to our results, G. biloba seemed to slow down the cognitive deterioration in patients with VCI, but the effect was shown in only one of the four neuropsychological tests administered. However, because of this mild effect in combination with a few adverse reactions, we cannot say that it is ineffective or unsafe either. Further studies are still needed to provide unambiguous evidence on the efficacy and safety of G. biloba extract. PMID:28243101

The Visual Scoring of Sleep in Infants 0 to 2 Months of Age.

PubMed

Grigg-Damberger, Madeleine M

2016-03-01

In March 2014, the American Academy of Sleep Medicine (AASM) Board of Directors requested the Scoring Manual Editorial Board develop rules, terminology, and technical specifications for scoring sleep/wake states in full-term infants from birth to 2 mo of age, cognizant of the 1971 Anders, Emde, and Parmelee Manual for Scoring Sleep in Newborns. On July 1, 2015, the AASM published rules for scoring sleep in infants, ages 0-2 mo. This evidence-based review summarizes the background information provided to the Scoring Manual Editorial Board to write these rules. The Anders Manual only provided criteria for coding physiological and behavioral state characteristics in polysomnograms (PSG) of infants, leaving specific sleep scoring criteria to the individual investigator. Other infant scoring criteria have been published, none widely accepted or used. The AASM Scoring Manual infant scoring criteria incorporate modern concepts, digital PSG recording techniques, practicalities, and compromises. Important tenets are: (1) sleep/wake should be scored in 30-sec epochs as either wakefulness (W), rapid eye movement, REM (R), nonrapid eye movement, NREM (N) and transitional (T) sleep; (2) an electroencephalographic (EEG) montage that permits adequate display of young infant EEG is: F3-M2, F4-M1, C3-M2, C4-M1, O1-M2, O2-M1; additionally, recording C3-Cz, Cz-C4 help detect early and asynchronous sleep spindles; (3) sleep onsets are more often R sleep until 2-3 mo postterm; (4) drowsiness is best characterized by visual observation (supplemented by later video review); (5) wide open eyes is the most crucial determinant of W; (6) regularity (or irregularity) of respiration is the single most useful PSG characteristic for scoring sleep stages at this age; (7) trace alternant (TA) is the only relatively distinctive EEG pattern, characteristic of N sleep, and usually disappears by 1 mo postterm replaced by high voltage slow (HVS); (8) sleep spindles first appear 44-48 w conceptional age (CA) and when present prompt scoring N; (9) score EEG activity in an epoch as "continuous" or "discontinuous" for inter-scorer reliability; (10) score R if four or more of the following conditions are present, including irregular respiration and rapid eye movement(s): (a) low chin EMG (for the majority of the epoch); (b) eyes closed with at least one rapid eye movement (concurrent with low chin tone); (c) irregular respiration; (d) mouthing, sucking, twitches, or brief head movements; and (e) EEG exhibits a continuous pattern without sleep spindles; (11) because rapid eye movements may not be seen on every page, epochs following an epoch of definite R in the absence of rapid eye movements may be scored if the EEG is continuous without TA or sleep spindles, chin muscle tone low for the majority of the epoch; and there is no intervening arousal; (12) Score N if four or more of the following conditions are present, including regular respiration, for the majority of the epoch: (a) eyes are closed with no eye movements; (b) chin EMG tone present; (c) regular respiration; and (d) EEG patterns of either TA, HVS, or sleep spindles are present; and (13) score T sleep if an epoch contains two or more discordant PSG state characteristics (either three NREM and two REM characteristics or two NREM and three REM characteristics). These criteria for ages 0-2 mo represent far more than baby steps. Like all the other AASM Manual rules and specifications none are fixed in stone, all open for debate, discussion and revision with the fundamental goal to provide standards for comparison of methods and results. A commentary on this article appears in this issue on page 291. © 2016 American Academy of Sleep Medicine.

Violin Pedagogy and the Physics of the Bowed String

NASA Astrophysics Data System (ADS)

McLeod, Alexander Rhodes

The paper describes the mechanics of violin tone production using non-specialist language, in order to present a scientific understanding of tone production accessible to a broad readership. As well as offering an objective understanding of tone production, this model provides a powerful tool for analyzing the technique of string playing. The interaction between the bow and the string is quite complex. Literature reviewed for this study reveals that scientific investigations have provided important insights into the mechanics of string playing, offering explanations for factors which both contribute to and limit the range of tone colours and dynamics that stringed instruments can produce. Also examined in the literature review are significant works of twentieth century violin pedagogy exploring tone production on the violin, based on the practical experience of generations of teachers and performers. Hermann von Helmholtz described the stick-slip cycle which drives the string in 1863, which replaced earlier ideas about the vibration of violin strings. Later, scientists such as John Schelleng and Lothar Cremer were able to demonstrate how the mechanics of the bow-string interaction can create different tone colours. Recent research by Anders Askenfelt, Knut Guettler, and Erwin Schoonderwaldt have continued to refine earlier research in this area. The writings of Lucien Capet, Leopold Auer, Carl Flesch, Paul Rolland, Kato Havas, Ivan Galamian, and Simon Fischer are examined and analyzed. Each author describes a different approach to tone production on the violin, representing a different understanding of the underlying mechanism. Analyzing these writings within the context of a scientific understanding of tone production makes it possible to compare these approaches more consistently, and to synthesize different concepts drawn from the diverse sources evaluated.

The responsible subject in the global age.

PubMed

Pulcini, Elena

2010-09-01

The first thesis of this article is that the concept of responsibility takes on an unprecedented meaning in the twentieth century resulting from the emergence of a new dimension of the other: to be responsible comes to mean not just to account for oneself in relation to the other, but also to take the other into account, to take care of the other-what I call responsibility towards (the other). The main reason for this change consists in the emergence of global risks and the necessity, as underlined by Hans Jonas, to be responsible for the destiny of the world and future generations. The problem, as explored in the article's second thesis, is that this implies the existence of a subject who is capable of responsibility. Jonas's insights on this point are insufficient, since he only recognizes duty as the fundament for his ethics of responsibility and thus neglects the problem of motivation. This is a particularly crucial problem today as we are witnessing the presence of a pathological subject, characterized by a split in his faculties (between doing and imagining, knowing and feeling). To underline this fact, this article makes use of Günther Anders's reflections, which provide a psycho-anthropological analysis of the subject, showing his pathologies and the necessity, from a moral perspective, to overcome his scission. Finally, this author suggests, as the article's third thesis, that this overcoming is the necessary fundament for the perception of risk, which in turn reinstates the subject's perception of his own vulnerability. Responsibility thus finds a motivation, which is neither altruistic nor duty-centred, in the awareness of our own vulnerability and the bond with the destiny of humankind as a whole.

The origin of ICM enrichment in the outskirts of present-day galaxy clusters from cosmological hydrodynamical simulations

NASA Astrophysics Data System (ADS)

Biffi, V.; Planelles, S.; Borgani, S.; Rasia, E.; Murante, G.; Fabjan, D.; Gaspari, M.

2018-05-01

The uniformity of the intracluster medium (ICM) enrichment level in the outskirts of nearby galaxy clusters suggests that chemical elements were deposited and widely spread into the intergalactic medium before the cluster formation. This observational evidence is supported by numerical findings from cosmological hydrodynamical simulations, as presented in Biffi et al., including the effect of thermal feedback from active galactic nuclei. Here, we further investigate this picture, by tracing back in time the spatial origin and metallicity evolution of the gas residing at z = 0 in the outskirts of simulated galaxy clusters. In these regions, we find a large distribution of iron abundances, including a component of highly enriched gas, already present at z = 2. At z > 1, the gas in the present-day outskirts was distributed over tens of virial radii from the main cluster and had been already enriched within high-redshift haloes. At z = 2, about 40 {per cent} of the most Fe-rich gas at z = 0 was not residing in any halo more massive than 10^{11} h^{-1} M_{⊙} in the region and yet its average iron abundance was already 0.4, w.r.t. the solar value by Anders & Grevesse. This confirms that the in situ enrichment of the ICM in the outskirts of present-day clusters does not play a significant role, and its uniform metal abundance is rather the consequence of the accretion of both low-metallicity and pre-enriched (at z > 2) gas, from the diffuse component and through merging substructures. These findings do not depend on the mass of the cluster nor on its core properties.

Chemical composition of Mars

USGS Publications Warehouse

Morgan, J.W.; Anders, E.

1979-01-01

The composition of Mars has been calculated from the cosmochemical model of Ganapathy and Anders (1974) which assumes that planets and chondrites underwent the same 4 fractionation processes in the solar nebula. Because elements of similar volatility stay together in these processes, only 4 index elements (U, Fe, K and Tl or Ar36) are needed to calculate the abundances of all 83 elements in the planet. The values chosen are U = 28 ppb, K = 62 ppm (based on K U = 2200 from orbital ??-spectrometry and on thermal history calculations by Tokso??z and Hsui (1978) Fe = 26.72% (from geophysical data), and Tl = 0.14 ppb (from the Ar36 and Ar40 abundances measured by Viking). The mantle of Mars is an iron-rich [Mg/(Mg + Fe) = 0.77] garnet wehrlite (?? = 3.52-3.54 g/cm3), similar to McGetchin and Smyth's (1978) estimate but containing more Ca and Al. It is nearly identical to the bulk Moon composition of Morgan et al. (1978b). The core makes up 0.19 of the planet and contains 3.5% S-much less than estimated by other models. Volatiles have nearly Moon-like abundances, being depleted relative to the Earth by factors of 0.36 (K-group, Tcond = 600-1300 K) or 0.029 (Tl group, Tcond < 600 K). The water abundance corresponds to a 9 m layer, but could be higher by as much as a factor of 11. Comparison of model compositions for 5 differentiated planets (Earth, Venus, Mars, Moon, and eucrite parent body) suggests that volatile depletion correlates mainly with size rather than with radial distance from the Sun. However, the relatively high volatile content of shergottites and some chondrites shows that the correlation is not simple; other factors must also be involved. ?? 1979.

Role of lichens in weathering of granodiorite in the Sila uplands (Calabria, southern Italy)

NASA Astrophysics Data System (ADS)

Scarciglia, Fabio; Saporito, Natalina; La Russa, Mauro F.; Le Pera, Emilia; Macchione, Maria; Puntillo, Domenico; Crisci, Gino M.; Pezzino, Antonino

2012-12-01

This paper explores the role of five recurrent epilithic lichen species (Aspicilia intermutans (Nyl.) Arnold, Xanthoparmelia pulla (Ach.) O. Blanco, A. Crespo, Elix, D. Hawksw. & Lumbsch, Rhizocarpon lecanorinum Anders, Tephromela atra (Huds.) Hafellner and Lecanora bolcana (Pollini) Poelt), which encrust granodiorite spheroidal boulders exposed in the Sila uplands (Calabria, southern Italy), in weathering of plutonic rocks in a typical mountainous Mediterranean environment. A detailed investigation was carried out on the lichen-rock interface of each species, by comparing them mutually and with lichen-free granodiorite samples. For this purpose, the lichen species were sampled together with the encrusted rock surface for detailed mineral-petrographic analyses performed in thin and ultra-thin sections. Optical and scanning electron microscopy of these sections and of bulk samples permitted us to highlight the peculiar modes of physical and chemical attacks of lichen thalli and hyphae on and into the substratum for each species. Crack systems often parallel to the outer rock surface appear often intruded by hyphae, which cause rupture of primary minerals, with detachment and progressive incorporation of their fragments into the thallus. In particular, the species L. bolcana and T. atra revealed an unexpected, partly endolithic behavior, presumably enhanced by the presence of rock fractures earlier generated by other physical breakage processes already affecting the spheroidal boulders in the Sila mountains. Dissolution features often affect primary minerals (even quartz), that may show very peculiar patterns which are suggestive of a biologically-induced control. Various phyllosilicate clay minerals were identified using SEM-EDS microprobe analyses and FT-IR spectroscopy, which also enabled the identification of possible amorphous silica (or quartz micrograins), rhizocarpic acid and carotenoid at the encrusted granodiorite interface. In contrast, neither oxalic acids nor oxalates were detected.

Evaluation of cytotoxic, analgesic, antidiarrheal and phytochemical properties of Hygrophila spinosa (T. Anders) whole plant.

PubMed

Bellah, S M Faysal; Islam, Md Nur; Karim, Md Rezaul; Rahaman, Md Masudur; Nasrin, Mst Samima; Rahman, Md Atiar; Reza, A S M Ali

2017-03-01

Synthetic drugs are going to be replaced by plant-derived traditional drugs due to their cost effectiveness, relatively less harmfulness, and efficacy against multidrug resistance organisms. Hygrophila spinosa (Acanthaceae) has been used in a wide range of ailments including flatulence, diarrhea, dysentery, gonorrhea, and menorrhagia. Therefore, we investigated the cytotoxic, antinociceptive, and antidiarrheal effects of H. spinosa ethanol extract (EExHs). Preliminary phytochemical screening was accomplished by established methods modified in experimental protocol. EExHs was undertaken for cytotoxic assay by Brine shrimp lethality bioassay, antinociceptive action by acetic acid induced writhing test, and antidiarrheal activity by castor oil induced antidiarrheal test. Data were analyzed by GraphPad Prism 6.0 software using Dunnett's test for multiple comparisons. Reducing sugar, steroid, glycoside, tannin, alkaloid, saponins, and flavonoids were found to be present in EExHs. Lethal concentration (LC50) of EExHs for brine shrimps was 50.59 µg/mL which was relatively lower than that of the standard drug vincristine sulfate. In acetic acid induced writhing test, oral administration of EExHs at three different doses (125, 250, and 500 mg/kg) decreased writhing in dose-dependent manner while the highest dose (500 mg/kg) achieved the maximum percentages of pain inhibition (58.8%). Diclofenac sodium (25 mg/kg) was used as a reference antinociceptive drug. The antidiarrheal action of EExHs was not found to be very promising for further use; however, the pure compounds from EExHs could be analyzed to justify the effects. This research demonstrates that the secondary metabolites guided cytotoxic and analgesic effects could be extensively studied in multiple models to confirm the effects.

Late Pleistocene lithostratigraphy and sequences in the southwestern Mesopotamia (Argentina): Evidences of the last interglacial stage

NASA Astrophysics Data System (ADS)

Ernesto, Brunetto; Soledad, Ferrero Brenda; Ignacio, Noriega Jorge

2015-03-01

The aim of this paper is to show the stratigraphic record of the Late Pleistocene corresponding to the distal region of the Paraná River basin. It displays sedimentological, paleontological and geochronological evidences that characterise the last interglacial-glacial cycle. In particular, strong environmental records are shown for the Last Interglacial Stage (LIS). Salto Ander Egg Formation (SAEF) is defined as a new lithostratigraphic unit representative of the Late Pleistocene in southwestern Mesopotamia. This unit is formed of complex fluvial deposits, which contains a heterogeneous collection of sub-environments, of ages ranging from 120 to 60 ky BP. The clast-supported gravel facies containing sparse boulders indicate high flow during a humid climate. The large and middle-scale architectures of fluvial sedimentary bodies evidence the relationship between the sediment accommodation and the sea level oscillations. Three sub-sequences identified in the succession suggest a transgressive trend during the MIS5e, a highstand stage in MIS5c, and a minor transgressive cycle during MIS3. A Brazilian faunal association collected at the bottom of the sequence and sedimentological interpretations display wet and warm climatic conditions, typical of tropical or subtropical environments. Such environmental conditions are characteristic of the maximum of the last interglacial stage (MIS5e) and show a signal stronger than the signal of the current interglacial stage. All these data show a direct correlation between the increases of paleodischarges and the elevation of the sea level. The whole sequence is completed with transitional swampy deposits, accumulated probably during the MIS3/MIS2 transition, and the typical loess of the Tezanos Pinto Formation, mantled during the Last Maximum Glacial.

Further examination of factors that influence preference for positive versus negative reinforcement.

PubMed

Kodak, Tiffany; Lerman, Dorothea C; Volkert, Valerie M; Trosclair, Nicole

2007-01-01

Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer during treatment (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Lalli et al., 1999). However, a number of variables may influence choice between concurrently available forms of reinforcement. An analogue for treatment situations in which positive reinforcement for compliance is in direct competition with negative reinforcement for problem behavior was used in the current study to evaluate several variables that may influence choice. Participants were 5 children who had been diagnosed with developmental disabilities and who engaged in problem behavior maintained by escape from demands. In the first phase, the effects of task preference and schedule of reinforcement on choice between a 30-s break and a high-preference food item were evaluated. The food item was preferred over the break, regardless of the preference level of the task or the reinforcement schedule, for all but 1 participant. In the second phase, the quality of the break was manipulated by combining escape with toys, attention, or both. Only 1 participant showed preference for the enriched break. In the third phase, choice of a medium- or low-preference food item versus the enriched break was evaluated. Three of 4 participants showed preference for the break over the less preferred food item. Results extend previous research by identifying some of the conditions under which individuals who engage in escape-maintained behavior will prefer a food reinforcer over the functional one.

Further Examination of Factors that Influence Preference for Positive Versus Negative Reinforcement

PubMed Central

Kodak, Tiffany; Lerman, Dorothea C; Volkert, Valerie M; Trosclair, Nicole

2007-01-01

Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer during treatment (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Lalli et al., 1999). However, a number of variables may influence choice between concurrently available forms of reinforcement. An analogue for treatment situations in which positive reinforcement for compliance is in direct competition with negative reinforcement for problem behavior was used in the current study to evaluate several variables that may influence choice. Participants were 5 children who had been diagnosed with developmental disabilities and who engaged in problem behavior maintained by escape from demands. In the first phase, the effects of task preference and schedule of reinforcement on choice between a 30-s break and a high-preference food item were evaluated. The food item was preferred over the break, regardless of the preference level of the task or the reinforcement schedule, for all but 1 participant. In the second phase, the quality of the break was manipulated by combining escape with toys, attention, or both. Only 1 participant showed preference for the enriched break. In the third phase, choice of a medium- or low-preference food item versus the enriched break was evaluated. Three of 4 participants showed preference for the break over the less preferred food item. Results extend previous research by identifying some of the conditions under which individuals who engage in escape-maintained behavior will prefer a food reinforcer over the functional one. PMID:17471792

The Efficacy of Melatonin for Sleep Problems in Children with Autism, Fragile X Syndrome, or Autism and Fragile X Syndrome

PubMed Central

Wirojanan, Juthamas; Jacquemont, Sebastien; Diaz, Rafael; Bacalman, Susan; Anders, Thomas F.; Hagerman, Randi J.; Goodlin-Jones, Beth L.

2009-01-01

Study Objective: To determine the efficacy of melatonin on sleep problems in children with autistic spectrum disorder (ASD) and fragile X syndrome (FXS). Methods: A 4-week, randomized, double blind, placebo-controlled, crossover design was conducted following a 1-week baseline period. Either melatonin, 3 mg, or placebo was given to participants for 2 weeks and then alternated for another 2 weeks. Sleep variables, including sleep duration, sleep-onset time, sleep-onset latency time, and the number of night awakenings, were recorded using an Actiwatch and from sleep diaries completed by parents. All participants had been thoroughly assessed for ASD and also had DNA testing for the diagnosis of FXS. Results: Data were successfully obtained from the 12 of 18 subjects who completed the study (11 males, age range 2 to 15.25 years, mean 5.47, SD 3.6). Five participants met diagnostic criteria for ASD, 3 for FXS alone, 3 for FXS and ASD, and 1 for fragile X premutation. Eight out of 12 had melatonin first. The conclusions from a nonparametric repeated-measures technique indicate that mean night sleep duration was longer on melatonin than placebo by 21 minutes (p = .02), mean sleep-onset latency was shorter by 28 minutes (p = .0001), and mean sleep-onset time was earlier by 42 minutes (p = .02). Conclusion: The results of this study support the efficacy and tolerability of melatonin treatment for sleep problems in children with ASD and FXS. Citation: Wirojanan J; Jacquemont S; Diaz R; Bacalman S; Anders TF; Hagerman RJ; Goodlin-Jones BL. The Efficacy of Melatonin for Sleep Problems in Children with Autism, Fragile X Syndrome, or Autism and Fragile X Syndrome. J Clin Sleep Med 2009;5(2):145-150. PMID:19968048

Characterization and risk of exposure to elements from artisanal gold mining operations in the Bolivian Andes.

PubMed

Pavilonis, Brian; Grassman, Jean; Johnson, Glen; Diaz, Yilmael; Caravanos, Jack

2017-04-01

Artisanal and small-scale gold mining (ASGM) offers low-skilled workers an opportunity to elevate themselves out of poverty. However, this industry operates with little to no pollution controls and the cost to the environment and human health can be large. The objectives of this study were to measure levels of arsenic (As), manganese (Mn), cobalt (Co), lead (Pb), and mercury (Hg) in the environment and characterize health risks to miners and residents in an area with active ASGM operations. An exposure assessment was conducted at two different mining sites and a nearby village in the Bolivian Anders. The resulting measurements were then used to quantify cancerous and noncancerous health risks to children and adults working at and living near ASGM areas. Soil concentrations of As were well above background levels and showed great variations between the village and mining area. Mercury vapor levels at the two mining sites were approximately 30 times larger than the EPA reference concentration. The risk of developing non-cancerous health effects were primarily due to exposure to As and Hg. The probability of individuals developing cancer was considerably increased with adult miners having a probability of 1.3 out of 100. Cancer potential was driven by exposure to As, with de minimus cancer risk from all other elements. Based on the environmental characterization of elements in soils and Hg vapors, the risk of developing cancerous and non-cancerous health outcomes were above a level of concern based on EPA risk assessment guidance. Personal protective equipment was not worn by workers and Hg amalgam is commonly heated in workers' homes. Better education of the risks of ASGM is needed as well as simple controls to reduce exposure. Published by Elsevier Inc.

Chapter 19: The age of scarplike landforms from diffusion-equation analysis

USGS Publications Warehouse

Hanks, Thomas C.

2000-01-01

The purpose of this paper is to review developments in the quantitative modeling of fault-scarp geomorphology, principally those since 1980. These developments utilize diffusionequation mathematics, in several different forms, as the basic model of fault-scarp evolution. Because solutions to the general diffusion equation evolve with time, as we expect faultscarp morphology to evolve with time, the model solutions carry information about the age of the structure and thus its time of formation; hence the inclusion of this paper in this volume. The evolution of fault-scarp morphology holds a small but special place in the much larger class of problems in landform evolution. In general, landform evolution means the evolution of topography as a function of both space and time. It is the outcome of the competition among those tectonic processes that make topography, erosive processes that destroy topography, and depositional processes that redistribute topography. Deposition and erosion can always be coupled through conservation-of-mass relations, but in general deposition occurs at great distance from the source region of detritus. Moreover, erosion is an inherently rough process whereas deposition is inherently smooth, as is evident from even casual inspection of shaded-relief, digital-elevation maps (e.g., Thelin and Pike, 1990; Simpson and Anders, 1992) and the current fascination with fractal representations oferoding terrains (e.g., Huang and Turcotte, 1989; Newman and Turcotte, 1990). Nevertheless, large-scale landform-evolution modeling, now a computationally intensive, advanced numerical exercise, is generating ever more realistic landforms (e.g., Willgoose and others, 1991a,b; Kooi and Beaumont, 1994; Tucker and Slingerland, 1994), although many of the rate coefficients remain poorly prescribed

On the instrumental characterization of a 3-λ scanning lidar to monitor industrial flames and its application for retrieving optical and microphysical properties

NASA Astrophysics Data System (ADS)

Guerrero-Rascado, Juan Luis; da Costa, Renata; Esteban Bedoya, Andrés; Guardani, Roberto; Alados-Arboledas, Lucas; Efrain Bastidas, Álvaro; Landulfo, Eduardo

2015-04-01

The emission of pollutants in megacities and industrial areas can have strong impact, not only from an environmental point of view, but also for human health. Cubatão (23° 53' S, 46° 26' W, 10 m asl) has been one of the most industrialized city in Brazil (located at São Paulo state coast) during the last decades. This work deals with the recent advances made on a 3-λ scanning lidar placed at this industrial region. Special attention has been paid to the characterization of the electronic performance of this lidar system. For this goal, the quality assurance tests, regularly applied in well-established lidar networks such as LALINET [Guerrero-Rascado et al., 2014] and EARLINET [Pappalardo et al. 2014], were applied to the Cubatão scanning lidar in order to improve the knowledge of its performing itself and to design protocols for correcting lidar signal for undesirable instrumental effects. The application of the results derived from these quality assurance tests together with the state-of-the-art methodologies to map the particle optical and microphysical properties inside industrial flares demonstrate the potential of this lidar for the study and measurement of industrial emissions. References: J. L. Guerrero-Rascado, E. Landulfo, J. C. Antuña, H. M. J. Barbosa, B. Barja, A. E. Bastidas, A. E. Bedoya, R. da Costa, R. Estevan, R. N. Forno, D. A. Gouveia, C. Jiménez, E. G. Larroza, F. J. S. Lopes, E. Montilla-Rosero, G. A. Moreira, W. M. Nakaema, D. Nisperuza, L. Otero, J. V. Pallotta, S. Papandrea, E. Pawelko, E. J. Quel, P. Ristori, P. F. Rodrigues, J. Salvador, M. F. Sánchez, and A. Silva, "Towards an instrumental harmonization in the framework of LAINET: dataset of technical specifications", Proceedings of SPIE 2014, vol. 9246, 92460O-1 -- 92460O-14, doi: 10.1117/12.2066873 (2014) G. Pappalardo, A. Amodeo, A. Apituley, A. Comerón, V. Freudenthaler, H. Linné, A. Ansmann, J. Bösenberg, G. D'Amico, I. Mattis, L. Mona, U. Wandinger, V. Amiridis, L. Alados-Arboledas, D. Nicolae, and M. Wiegner, "EARLINET: towards an advanced sustainable European aerosol lidar network," Atmos. Meas. Tech. 7(8), 2389-2409 (2014)

Convergent and divergent intranetwork and internetwork connectivity patterns in patients with remitted late-life depression and amnestic mild cognitive impairment.

PubMed

Chen, Jiu; Shu, Hao; Wang, Zan; Zhan, Yafeng; Liu, Duan; Liao, Wenxiang; Xu, Lin; Liu, Yong; Zhang, Zhijun

2016-10-01

Both remitted late-life depression (rLLD) and amnesiac mild cognitive impairment (aMCI) alter brain functions in specific regions of the brain. They are also disconnection syndromes that are associated with a high risk of developing Alzheimer's disease (AD). Resting-state functional connectivity magnetic resonance imaging (rs-fcMRI) was performed to define the shared and distinct aberrant patterns in intranetwork and internetwork connectivity between rLLD and aMCI and to determine how knowledge of these differences might contribute to our essential understanding of the altered sequences involved in functional systems both inside and outside of resting-state networks. We used rs-fcMRI to investigate in five functionally well-defined brain networks in two large cohorts of subjects at high risk for AD (55 rLLD and 87 aMCI) and 114 healthy controls (HC). A reduced degree of functional connectivity was observed in the bilateral inferior temporal cortex and supplemental motor area, and reduced correlations were observed within the sensory-motor network (SMN) and in the default mode network (DMN)-control network (CON) pair in the rLLD group than the HC group. The aMCI group showed only focal functional changes in regions of interest pairs, a trend toward increased correlations within the salience network and SMN, and a trend toward a reduced correlation in the DMN-CON pair. Furthermore, the rLLD group exhibited more severely altered functional connectivity than the aMCI group. Interestingly, these altered connectivities were associated with specific multi-domain cognitive and behavioral functions in both rLLD and aMCI. The degree of functional connectivity in the right primary auditory areas was negatively correlated with Hamilton Depression Scale scores in rLLD. Notably, altered connectivity between the right middle temporal cortex and the posterior cerebellum was negatively correlated with Mattis Dementia Rating Scale scores in both rLLD and aMCI. These results demonstrate that rLLD and aMCI may share convergent and divergent aberrant intranetwork and internetwork connectivity patterns as a potential continuous spectrum of the same disease. They further suggest that dysfunctions in the right specific temporal-cerebellum neural circuit may contribute to the similarities observed in rLLD and aMCI conversion to AD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Intraläsionale Therapie niedrig maligner primär kutaner B-Zell-Lymphome mit Anti-CD20-Antikörper: Nebenwirkungen korrelieren mit gutem klinischen Ansprechen.

PubMed

Eberle, Franziska C; Holstein, Julia; Scheu, Alexander; Fend, Falko; Yazdi, Amir S

2017-03-01

Die intraläsionale Gabe von Anti-CD20-Antikörpern (Rituximab) wurde als effektive Therapieoption für Patienten mit niedrig malignen primär kutanen B-Zell-Lymphomen beschrieben. Bis heute wurden allerdings keine Parameter identifiziert, welche reproduzierbar ein gutes klinisches Ansprechen dieser Therapie vorhersagen. Ziel dieser Studie ist, sowohl das klinische Ansprechen und die unerwünschten Nebenwirkungen als auch die Patientenwahrnehmung hinsichtlich intraläsionaler Injektionen von anti-CD20-Antikörpern zur Behandlung indolenter primär kutaner B-Zell-Lymphome im Vergleich mit anderen Therapien zu evaluieren. Elf Patienten mit einem primär kutanen B-Zell-Lymphom, namentlich primär kutanes Keimzentrumslymphom (n = 9) und primär kutanes Marginalzonenlymphom (n = 2), welche mittels intraläsionalem Anti-CD20-Antikörper behandelt wurden, wurden retrospektiv evaluiert hinsichtlich der Ansprechrate und unerwünschter Nebenwirkungen sowie in Bezug auf deren Selbsteinschätzung dieser und anderer Therapien des primär kutanen B-Zell-Lymphoms. Patienten, deren primär kutanes B-Zell-Lymphom mittels intraläsionaler Gabe von Anti-CD20-Antikörper behandelt wurde, zeigten ein komplettes oder partielles Ansprechen in 45 % beziehungsweise 27 % aller Patienten. Speziell Patienten mit grippeähnlichen Symptomen nach erfolgter Injektion zeigten ein gutes Ansprechen. Die Mehrheit der Patienten empfand die Therapie mit Rituximab als die beste Therapie im Vergleich zu anderen Therapien wie beispielsweise chirurgische Exzision oder Radiotherapie. Intraläsionales Rituximab ist eine effektive Therapie mit hoher Patientenzufriedenheit. Starke therapiebedingte Nebenwirkungen wie Fieber, Schüttelfrost und Kopfschmerzen nach Gabe von Rituximab könnten als Indikator für gute Wirksamkeit dienen. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Indirect Coupling of Magnetic Layers via Domain Wall Fringing fields

NASA Astrophysics Data System (ADS)

Parkin, Stuart

2001-03-01

Ferromagnetic films separated by thin metallic spacer layers are usually coupled through an indirect exchange interaction which oscillates in sign between ferro and antiferromagnetic coupling as a function of the spacer layer thickness^1. For both such metallic systems, and for multilayered systems in which the ferromagnetic films are separated by thin insulating layers, correlated roughness of the magnetic layers gives rise to a weak ferromagnetic coupling via dipole fields. Another type of dipolar coupling mechanism, which has largely been ignored, is that arising from domain wall fringing fields. These fields can be locally very large^2 and can result in the demagnetization of ferromagnetic films which are nominally highly coercive ("hard") in sandwiches comprised of "hard" and "soft" ferromagnetic layers. When the moment of the soft layer is reversed back and forth in small magnetic fields, much too small to affect the moment of the hard layer, substantial local fringing fields from domain walls created in the soft film gradually result in the demagnetization of the hard film. In some cases the moment of the hard layer decays in an oscillatory manner as it is successively partially demagnetized and remagnetized. This process has been observed on both macroscopic and microscopic length scales using SQUID magnetometry and high resolution photoemission electron microscopy, respectively^3. Magnetic interactions from domain wall fringing fields may be very important for magnetic devices, especially, magnetoresistance sensors and memory elements. [1] S.S.P. Parkin, N. More and K.P. Roche, Phys. Rev. Lett. 64, 2304 (1990); S.S.P. Parkin, Phys. Rev. Lett., 67, 3598 (1991). [2] L. Thomas, M. Samant and S.S.P. Parkin, Phys. Rev. Lett. 84, 1816 (2000). [3] L. Thomas, J Lüning, A. Scholl, F. Nolting, S. Anders, J. Stöhr and S.S.P. Parkin, Phys. Rev. Lett. 84, 3462 (2000).

Stratigraphic reconnaissance of the Middle Jurassic Red Glacier Formation, Tuxedni Group, at Red Glacier, Cook Inlet, Alaska

USGS Publications Warehouse

LePain, David L.; Stanley, Richard G.

2015-01-01

The Alaska Division of Geological & Geophysical Surveys (DGGS) and U.S. Geological Survey (USGS) are implementing ongoing programs to characterize the petroleum potential of Cook Inlet basin. Since 2009 this program has included work on the Mesozoic stratigraphy of lower Cook Inlet, including the Middle Jurassic Tuxedni Group between Tuxedni and Iniskin bays (LePain and others, 2013; Stanley and others, 2013; fig. 5-1). The basal unit in the group, the Red Glacier Formation (fig. 5-2), is thought to be the principal source rock for oil produced in upper Cook Inlet, and available geochemical data support this contention (Magoon and Anders, 1992; Magoon, 1994). Despite its economic significance very little has been published on the formation since Detterman and Hartsock’s (1966) seminal contribution on the geology of the Iniskin–Tuxedni area nearly 50 years ago. Consequently its stratigraphy, contact relations with bounding formations, and source rock characteristics are poorly known. During the 2014 field season, a nearly continuous stratigraphic section through the Red Glacier Formation in its type area at Red Glacier was located and measured to characterize sedimentary facies and to collect a suite of samples for analyses of biostratigraphy, Rock-Eval pyrolysis, vitrinite reflectance, and sandstone composition (fig. 5-3).The poorly known nature of the Red Glacier Formation is likely due to its remote location, steep terrain, and the fact that the type section is split into two segments that are more than 3 km apart. The lower 375 m segment of the formation is on the ridge between Red Glacier and Lateral Glacier and the upper 1,009 m segment is on the ridge between Red Glacier and Boulder Creek (fig. 5-3). Structural complications in the area add to the difficulty in understanding how these two segments fit together.

Osmium-Iridium Correlation and Osmium Isotopic Composition in Some Geological Boundaries and Meteorites

NASA Astrophysics Data System (ADS)

Liu, Y. Z.; Wang, J. X.; Mao, X. Y.; Chai, C. F.

1992-07-01

Since the pioneering study of Alvarez et al. on K/T boundary event, Ir has long been considered to be the main indicator of extraterrestrial materials in boundaries, while little work about Os and its isotopic composition have been done. In this work a sophisticated radiochemical separation procedure together with neutron activation analsis (NAA) method was established for the determination of Os in some geological boundaries (P epsilon/epsilon, K/T, D/C, O/S, P/T). Combined with our early work--determination of Ir abundances [1], the sources of boundary events were deciphered by using the Os/Ir ratios. Simultaneously ^184Os/^190Os ratios in K/T boundaries, as well as inclusions of Allende chondrite and acid-insoluble residues of iron meteorites (Nandan, Jianshi, Longchang) were determined to search for the Os isotopic composition anomalies resulted from the extrasolar components by RNAA. The results show that the Os abundances exhibit a positive correlation with the Ir abundances for overall K/T boundary samples, but only the Os/Ir ratios of K/T boundaries, with the average of 0.98 +- 0.55, are in excellent agreement with 1.01 of the solar system [2], Accordingly, it provides new evidence for an extraterrestrial source of the K/T event. The results of ^184Os/^190Os ratios, with uncertainties of less than 1%, indicate there is no remarkable ^184Os/^190Os ratio anomaly in the K/T boundary samples, which implies the impacting matter may be from the solar system not the extrasolar, while no anomaly exists in the inclusions of Allende chondrite and acid-insoluble residues of iron meteorites, which disagree with the results obtained by Goel [3]. REFERENCES [1] Chai Chifang (1988) Isotopenpraxis 24, pp. 257-272. [2] Anders E. and Grevesse N. (l989) Geochim. Cosmochim. Acta 53, 197-214. [3] Goel P.S.(1987) Proc. Indian Acad. Sci. (Earth Planet. Sci), 96, pp. 81-102.

OMEGACAM and Gravitational Lensing

NASA Astrophysics Data System (ADS)

Christen, Fabrice Frédéric Thiébaut

2007-04-01

Het proefschrift van Fabrice Christen gaat over de ontwikkeling van nieuwe methoden voor het corrigeren van (digitale) foto's van melkwegstelsels. Met deze methoden kunnen de beelden uit het heelal beter worden geanalyseerd. Het eerste gedeelte is gewijd aan het werk dat bij ESO is uitgevoerd aan de CCD's van de OmegaCAM camera, het enige instrument van de VST. OmegaCAM is een optische groothoekcamera met een beeldveld van een vierkante graad, opgebouwd uit een mozaiek van 8 bij 4 CCD's. Van elk onderdeel moeten alle kenmerken volledig bekend zijn voordat het in het CCD mozaiek geplaatst kan worden. In het tweede deel van dit proefschrift wordt de ontwikkeling van een nieuwe methode voor het corrigeren van de ``point-spread function'' (PSF) en schatten van de ellipticiteit van de melkwegstelsels besproken. De nieuwe techniek wordt getest en vergeleken met een door sterrenkundigen algemeen gebruikte methode in het veld van zwaartekrachtslenzen, de Kaiser, Squire en Broadhurst (KSB) methode. De nieuwe methode, gebaseerd op shapelet ontleding (vergelijkbaar met wavelet ontleding), gaat verder, en is sneller en theoretisch preciezer dan de KSB methode. Door gebruik te maken van de gecorrigeerde ellipticiteit, kunnen we een statistische analyse uitvoeren om er een kosmisch vervormingssignaal uit te halen. De licht vervormde beelden van de melkwegstelsels bewij zen dat de niet-homogene massaverdeling op megaparsec-schaal voornamelijk bestaat uit grote hoeveelheden donkere materie. Verder vergelijken we de schattingen van de ellipticiteit van de shapelet en KSB methode. Bovendien voeren we ook nog een melkwegstelsel-melkwegstelsel lens analyse uit op de 50 VLT Fors1 afbeeldingen en slagen we erin de belangrijkste eigenschappen van de halo's van de stelsels, die zich op een afstand van een- tot tweeduizend megaparsec (1 parsec = 3,26 lichtjaar = 3,085 x 10^16 meter) bevinden, te bepalen door gebruik te maken van twee modellen van melkwegstelselhalo's. Vergeleken met andere overzichtsmetingen vinden we vergelijkbare resultaten.

INTERACT-II campaign:comparison of commercial lidars and ceilometers with advanced multi-wavelength Raman lidars

NASA Astrophysics Data System (ADS)

Rosoldi, Marco; Madonna, Fabio; Pappalardo, Gelsomina; Vande Hey, Joshua; Zheng, Yunhui; Vaisala Team

2017-04-01

Knowledge of aerosol spatio-temporal distribution in troposphere is essential for the study of climate and air quality. For this purpose, global scale high resolution continuous measurements of tropospheric aerosols are needed. Global coverage high resolution networks of ground-based low-cost and low-maintenance remote sensing instruments, such as commercial automatic lidars and ceilometers, can strongly contribute to this scientific mission. Therefore, it is very interesting for scientific community to understand to which extent these instruments are able to provide reliable aerosol measurements and fill in the geographical gaps of existing networks of the advanced lidars, like EARLINET (European Aerosol Research LIdar NETwork). The INTERACT-II (INTERcomparison of Aerosol and Cloud Tracking) campaign, carried out at CIAO (CNR-IMAA Atmospheric Observatory) in Tito Scalo, Potenza, Italy (760m a.s.l., 40.60°N, 15.72°E), aims to evaluate the performances of commercial automatic lidars and ceilometers for tropospheric aerosol profiling. The campaign has been performed in the period from July 2016 to January 2017 in the framework of ACTRIS-2 (Aerosol Clouds Trace gases Research InfraStructure) H2020 research infrastructure project. Besides the commercial ceilometers operational at CIAO (VAISALA CT25K and Luftt CHM15k), the performance of a CL51 VAISALA ceilometer, a Campbell CS135 ceilometer and a mini-Micro Pulse Lidar (MPL) have been assessed using the EARLINET multi-wavelengths Raman lidars operative at CIAO as reference. Following a similar approach used in the first INTERACT campaign (Madonna et al., AMT 2015), attenuated backscatter coefficient profiles and signals obtained from all the instruments have been compared, over a vertical resolution of 60 meters and a temporal integration ranging between 1 and 2 hours, depending on the observed atmospheric scenario. CIAO lidars signals have been processed using the EARLINET Single Calculus Chain (SCC) also with the aim to improve the data consistency and comparability (D'Amico et al., 2016; Mattis et al., 2016). A first statistical analysis of simultaneous observations performed by all the instruments during the campaign reveals that ceilometers have fairly good performances in aerosol profiling in the lower troposphere, up to an altitude of about 2000 m above the ground, but they are limited at higher altitudes. Among the considered devices, the mini-MPL shows the best performances with discrepancies limited to 10 % throughout the troposphere. Further analysis is ongoing also to assess the stability of the considered lidar technologies with respect to variation of working and environment temperature, aerosol loading, laser operation.

Do Carbynes Exist as Interstellar Material After All?

NASA Astrophysics Data System (ADS)

Gilkes, K. W. R.; Gaskell, P. H.; Russell, S. S.; Arden, J. W.; Pillinger, C. T.

1992-07-01

In the early 1980s, it was speculated that various linear polytypes of carbon consisting of alternating single and triple bonds, and having the generic name carbyne, might be carriers of anomalous noble gases (Whittaker et al., 1980). Doubts were, however, expressed (Smith and Buseck, 1982) concerning the identification of carbynes within the meteorite residues studied by Whittaker et al. (1980). In fact, the very existence of a new allotropic form of carbon was questioned: was it indeed a mineral called chaoite present in ejecta from the Ries Crater, as suggested by El Goresy and Donnay (1968), and had it been made in the laboratory by condensation of a carbon vapor (Kasatochkin et al., 1967)? Since 1981 it has become apparent that acid residues prepared for the purpose of isolating the carrier of the noble gas component Xe(HL) are largely nm-sized diamond together with some amorphous diamond-like material (Lewis et al., 1987). While attempting to study the latter by high- resolution transmission, electron microscopy (HRTEM) using a residue (MIL) prepared from Murchison by HF/HCl/Cr2O7^2-/HClO4 treatment, we found crystalline regions with interplanar spacings higher than diamond (0.2 nm), silicon carbide (0.26 nm), and graphite (0.2 nm, 0.34 nm). We have acquired HRTEM images, SAED patterns, and EDX spectra from several of these particles, which tend to be very small, typically 10 nm, and therefore not likely to be airborne contaminants. Lattice images that match the {110} and {203} spacings of chaoite have been found for single crystals. The interplanar spacings calculated from the hexagonal electron diffraction data (using diamond as internal standard) can be compared favorably with chaoite (El Goresy and Donnay, 1968). EDX spectra for most grains show no evidence of elements with atomic number greater than 11 (Na), although in one or two cases peaks for Ca from an unknown source were observed. Diffraction data from Ca- contamined areas were not used for comparison with chaoite. An attempt has been made to obtain electron energy loss spectra (EELS) from individual crystals, so far without success because of their small size and fragility. EELS data with a characteristic carbon K edge, distinct from amorphous carbon, graphite, and diamond, have been obtained, however, from unspecified areas on the sample; the absence of any Si edges rules out the possibility of silicate contamination. Single crystals and microcrystalline material, having similar SAED patterns to the component found in meteorite residues, can be found in abundance in white carbon films deposited on a variety of substrates using plasma and arc techniques. Such materials are very low in Si abundance but contain some Fe. The existence of carbynes at the few percent level in acid residues from primitive meteorites in association with diamond, a material believed to be of presolar origin on the basis of isotopic characteristics, strongly suggests an analogous provenance to the linear carbon allotropes. Verchovsky et al. (this volume) have discussed the existence of an additional anomalous xenon host phase intimately coexisting with meteorite diamond. Given that if diamond is the carrier of Xe(HL), only one crystal in 3 x 10^6 actually contains a noble gas atom, carbynes may still have a role to play in understanding the first recognized noble gas isotope anomaly. A substantial body of astronomical observational data has been acquired documenting the presence of alternating single and triple carbon bonds in space: suggestions (Webster, 1980) that carbynes are a component of interstellar dust need to be further considered. The occurrence of triple- bonded species as grain material is particularly appealing, because cyano groups are common in interstellar molecules, and the exact location of istopically light nitrogen in primitive meteorite acid residues is still under active investigation (Russell et al., 1991). References: El Goresy A. and Donnay G. (1968) Science 216, 984-986. Kasatochkin V. I., Sladkov A. M., Kudryaytsev, Popov N. M., and Korshak V. V., Dokl. Acad. Nauk. SSSR, 177, 358-360. Lewis R. S., Ming T., Walker J. F., Anders E., and Steel E. (1987) Nature 326, 160-164. Russell S. S., Arden J. W., and Pillinger C. T. (1991) Science 254, 1188-1191. Smith P. P. K. and Buseck P. R. (1982) Science 216, 984-986. Webster A. S. (1980) Mon. Not. R. Astron. Soc. 192, 7P-9P. Whittaker A. G., Watts E. J., Lewis R. S., and Anders E. (1980) Science 209, 1512-1514.

SEP-Kr and SEP-Xe in Lunar Ilmenite and the Ar/Kr/Xe Ratio in the Solar Wind

NASA Astrophysics Data System (ADS)

Wieler, R.; Baur, H.; Signer, P.

1992-07-01

We analyzed all five noble gases in an ilmenite sample from lunar soil 71501 by closed system stepped etching (CSSE), thus extending our CSSE studies of solar noble gases (Wieler et al., 1986; Benkert et al., 1988) to Kr and Xe. He, Ne, Ar isotopes: We observe the familiar presence of two solar noble gas components: step 1 shows ^4He/^3He = 2250, ^20Ne/^22Ne = 13.8, and ^36Ar/^38Ar=5.46. The first two ratios are essentially identical to modern solar wind values (SWC; Geiss, 1973), indicating an isotopically unfractionated SW noble gas reservoir in lunar ilmenite. The Ne data-points of later steps fall on a straight line and reach the SEP-Ne point (^20Ne/^22Ne = 11.3). The slope of this line indicates mass dependent fractionation between SW-Ne and SEP-Ne. SEP-He (^4He/^3He = 4650 +-100) and SEP-Ar (^36Ar/^38Ar = 4.89+-0.05) are also observed (latter two numbers slightly revised compared to Wieler et al., 1992). Kr, Xe isotopes: Kr in those two steps that release pure SW-Ne is very slightly lighter than atmospheric Kr (^86Kr/^84Kr = 0.3041; see also Wieler et al., 1992). We interpret this to be SW-Kr in soil 71501. Steps containing (isotopically heavier) SEP-Ne likewise release heavier Kr, interpreted accordingly as SEP-Kr (^86Kr/^84Kr = 0.323). Similarly, a light Xe component is released first (SW-Xe, ^136Xe/^132Xe = 0.3003), followed by heavier SEP-Xe (^136Xe/^132Xe = 0.319). The data are consistent with both Kr and Xe in SW and SEP components to be related by mass fractionation. The relation first proposed by Benkert et al. (1988) between a ratio R(m(sub)2,m(sub)1) of two isotopes with masses m(sub)2>m(sub)1 in SW and SEP now holds for all five noble gases: (R(sub)SW-R(sub)SEP)/R(sub)SW = (2+-0.13)*(m(sub)2- m(sub)1)/m(sub)2. Since m(sub)2~m(sub)1, this relation may also be written as: R(sub)SEP/R(sub)SW ~ (m(sub)1/m(sub)2)^2 (Geiss and Bochsler, 1991). Element ratios: ^4He/^36Ar and ^20Ne/^36Ar rise from values several times below SWC to essentially SWC ratios in the steps releasing nearly pure SEP gases, indicating element fractionation between SW-He/Ne, but essentially unfractionated SEP-He/Ne/Ar in lunar ilmenite. In contrast, Kr/Xe stays virtually constant (^84Kr/^132Xe = 8.4+-0.5), except in the first few steps. If the light three noble gases indeed are not fractionated in the SEP dominated steps, we would also expect no fractionation for Kr/Xe. The measured ^84Kr/^132Xe ratio is, however, about 2.4 times lower than the most recent "solar system" ratio (Anders and Grevesse, 1989), albeit only ~30% lower than the "solar" value preferred by Marti and Suess (1988). Kr/Xe ratios similar to those in ilmenites have been found earlier, e.g. in Peysanoe (Marti, 1969). They are often taken to indicate fractionated loss of solar noble gases. Based on the new CSSE results, we propose, instead, that lunar ilmenites retain a faithful record of ^84Kr/^132Xe in SW and SEP (and also ^36Ar/^84Kr(sub)SW = 1750+- 300). If so, this may indicate noble gas fractionation in the solar corpuscular radiation, perhaps depending on first ionization potential or a related parameter. Work supported by the Swiss National Science Foundation. References: Anders, E. and Grevesse, N. (1989) Geochim. Cosmochim. Acta. 53, 197-214. Benkert, J.-P. et al. (1988) Lunar Planet. Sci. (abstract) 19, 59-60. Geiss, J. (1973) Proc. 13th Int. Cosmic Ray Conf. 3375-3398. Geiss, J. and Bochsler, P. (1991) In The Sun in Time (eds. C. P. Sonett, M. S. Giampapa and M.S. Matthews), pp. 98-117. Univ. Arizona Press, Tucson, Arizona. Marti, K. (1969) Science. 166. 1263-1265. Marti, K. and Suess, H. E. (1988) Astrophys. Space Sci. 144. 507-517. Wieler, R. et al. (1986) Geochim. Cosmochim. Acta. 50. 1997-2017. Wieler, R. et al. (1992) Lunar Planet. Sci. (abstract) 23.

Somewhere beyond the sea? The oceanic - carbon dioxide - reactions

NASA Astrophysics Data System (ADS)

Meisinger, Philipp; Wittlich, Christian

2014-05-01

In correlation to climate change and CO2 emission different campaigns highlight the importance of forests and trees to regulate the concentration of carbon dioxide in the earths' atmosphere. Seeing millions of square miles of rainforest cut down every day, this is truly a valid point. Nevertheless, we often tend to forget what scientists like Spokes try to raise awareness for: The oceans - and foremost deep sea sections - resemble the second biggest deposit of carbon dioxide. Here carbon is mainly found in form of carbonate and hydrogen carbonate. The carbonates are needed by corals and other sea organisms to maintain their skeletal structure and thereby to remain vital. To raise awareness for the protection of this fragile ecosystem in schools is part of our approach. Awareness is achieved best through understanding. Therefore, our approach is a hands-on activity that aims at showing students how the carbon dioxide absorption changes in relation to the water temperature - in times of global warming a truly sensitive topic. The students use standard syringes filled with water (25 ml) at different temperatures (i.e. 10°C, 20°C, 40°C). Through a connector students inject carbon dioxide (25ml) into the different samples. After a fixed period of time, students can read of the remaining amount of carbon dioxide in relation to the given water temperature. Just as with every scientific project, students need to closely monitor their experiments and alter their setups (e.g. water temperature or acidity) according to their initial planning. A digital template (Excel-based) supports the analysis of students' experiments. Overview: What: hands-on, minds -on activity using standard syringes to exemplify carbon dioxide absorption in relation to the water temperature (Le Chatelier's principle) For whom: adjustable from German form 11-13 (age: 16-19 years) Time: depending on the prior knowledge 45-60 min. Sources (extract): Spokes, L.: Wie Ozeane CO2 aufnehmen. Environmental Sciences. University of East Anglia, Norwich 2007. Von Borstel, G. und Böhm, A.: Le Chatelier einmal anders, Gleichgewichtsverschiebungen am Kontext Sprudelwasser. Naturwissenschaft im Unterricht Chemie 6 (2006) H. 96, S. 34-37

Interstellar detection of the intersystem line Si II lambda 2335 toward zeta Ophiuchi

NASA Technical Reports Server (NTRS)

Cardelli, Jason A.; Sofia, Ulysses J.; Savage, Blair D.; Keenan, Francis P.; Dufton, Philip L.

1994-01-01

We report on the detection of the weak intersystem transistion of Si II lambda 2335 A in the sight line toward zeta Oph using the Ech-B mode (3.5 km/s resolution) of the Goddard High Resolution Spectrograph. The high-quality spectrum is characterized by an empirically measured signal-to-noise of 450, in excellent agreement with that expected from photon-statistics. The measured equivalent width of the Si II line is W(sub lambda) = 0.48 +/- 0.12 mA. Using the new experimental f-value of Calamai, Smith, and Bergeson, we find a Si II column density of 2.34 (+/- 0.58) x 10(exp 15) atoms/sq cm and (Si/H)(sub zeta Oph) = 1.78 (+/- 0.44) x 10(exp -6) for the principal absorbing component(s) at v(sub sun) approx. = -15 km/s. Analysis of the Si II lambda 1808 absorption over the same velocity range using the new experimental f-value of Bergeson & Lawler yields a column density (corrected for saturation) that is consistent within the weak line errors and confirms the relative accuracies of these new f-values. Furthermore, these results indicate that accurate abundances can now be derived for Si II, particularly from the weak Si II lambda 2335 A since it is free of saturation effects. For the zeta Oph v(sub sun) approx. = -15 km/s component(s), we find that greater than 95% of the available cosmic abundance (i.e. the 1989 meteoritic abundances of Anders & Grevesse) of Mg, Fe, and Si is 'missing' from the gas phase and is presumably locked up in the dust. These elements are present in the dust grains in ratios of Fe/Si approximately equals 0.9 and Mg/Si approximately equals 1.1, consistent with the ratio of their cosmic abundances. These ratios are in sharp contrast to more diffuse clouds like those seen toward the high-latitude halo star HD 93521 where in the dust Fe/Si approximately equals 1.8 and Mg/Si approximately equals 2.1.

Earthrise: The 45th Anniversary

NASA Image and Video Library

2013-12-23

In December of 1968, the crew of Apollo 8 became the first people to leave our home planet and travel to another body in space. But as crew members Frank Borman, James Lovell, and William Anders all later recalled, the most important thing they discovered was Earth. Using photo mosaics and elevation data from Lunar Reconnaissance Orbiter (LRO), this video commemorates the 45th anniversary of Apollo 8's historic flight by recreating the moment when the crew first saw and photographed the Earth rising from behind the Moon. Narrator Andrew Chaikin, author of A Man on the Moon, sets the scene for a three-minute visualization of the view from both inside and outside the spacecraft accompanied by the onboard audio of the astronauts. The visualization draws on numerous historical sources, including the actual cloud pattern on Earth from the ESSA-7 satellite and dozens of photographs taken by Apollo 8, and it reveals new, historically significant information about the Earthrise photographs. It has not been widely known, for example, that the spacecraft was rolling when the photos were taken, and that it was this roll that brought the Earth into view. The visualization establishes the precise timing of the roll and, for the first time ever, identifies which window each photograph was taken from. The key to the new work is a set of vertical stereo photographs taken by a camera mounted in the Command Module's rendezvous window and pointing straight down onto the lunar surface. It automatically photographed the surface every 20 seconds. By registering each photograph to a model of the terrain based on LRO data, the orientation of the spacecraft can be precisely determined. Credit: NASA's Scientific Visualization Studio NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA Google+ Hangout: 'Earthrise' A New Visualization - 45th Anniversary of Apollo 8 Viewing Earth from Space

NASA Image and Video Library

2013-12-19

Join NASA's Google+ Hangout on Friday, December 20th 2:00 - 3:00 PM (EST) at go.nasa.gov/18S2TbC It was 45 years ago, on December 24, 1968 when Apollo 8 astronauts captured 'Earthrise' – the first color photograph of Earth taken by a person in lunar orbit. NASA announces a new simulation of the events leading to the creation of 'Earthrise,' one of the iconic photographs of the 20th Century – Earth seen from the moon captured by the crew of Apollo 8. This new simulation allows anyone to virtually ride with the astronauts and experience the awe they felt at the vista in front of them. Apollo 8 Commander Frank Borman and crew members William A. Anders and James A. Lovell photographed the stunning scene as their spacecraft orbited the moon on December 24, 1968. The new computer simulation was created using data from NASA's Lunar Reconnaissance Orbiter, or LRO, spacecraft and includes details not seen in the previous visualization released last year. Participants in this Hangout include: * John Keller, project scientist for the Lunar Reconnaissance Orbiter project * Ernie Wright, project lead with the Scientific Visualization Studio at NASA Goddard Space Flight Center * Andrew Chaikin, space historian, author of the book A Man on the Moon "This will also be the first time we've released a video that's synchronized with the onboard audio recording of the astronauts,", says Ernie Wright. "The new visualization tells us not only what time the photos were taken, but also exactly which way the spacecraft was pointing and therefore which window each photo was taken from." Earthrise is the cover photo of TIME's Great Images of the 20th Century and is among photos on the cover of LIFE's 100 Photographs That Changed the World. NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Power estimation on functional level for programmable processors

NASA Astrophysics Data System (ADS)

Schneider, M.; Blume, H.; Noll, T. G.

2004-05-01

In diesem Beitrag werden verschiedene Ansätze zur Verlustleistungsschätzung von programmierbaren Prozessoren vorgestellt und bezüglich ihrer Übertragbarkeit auf moderne Prozessor-Architekturen wie beispielsweise Very Long Instruction Word (VLIW)-Architekturen bewertet. Besonderes Augenmerk liegt hierbei auf dem Konzept der sogenannten Functional-Level Power Analysis (FLPA). Dieser Ansatz basiert auf der Einteilung der Prozessor-Architektur in funktionale Blöcke wie beispielsweise Processing-Unit, Clock-Netzwerk, interner Speicher und andere. Die Verlustleistungsaufnahme dieser Bl¨ocke wird parameterabhängig durch arithmetische Modellfunktionen beschrieben. Durch automatisierte Analyse von Assemblercodes des zu schätzenden Systems mittels eines Parsers können die Eingangsparameter wie beispielsweise der erzielte Parallelitätsgrad oder die Art des Speicherzugriffs gewonnen werden. Dieser Ansatz wird am Beispiel zweier moderner digitaler Signalprozessoren durch eine Vielzahl von Basis-Algorithmen der digitalen Signalverarbeitung evaluiert. Die ermittelten Schätzwerte für die einzelnen Algorithmen werden dabei mit physikalisch gemessenen Werten verglichen. Es ergibt sich ein sehr kleiner maximaler Schätzfehler von 3%. In this contribution different approaches for power estimation for programmable processors are presented and evaluated concerning their capability to be applied to modern digital signal processor architectures like e.g. Very Long InstructionWord (VLIW) -architectures. Special emphasis will be laid on the concept of so-called Functional-Level Power Analysis (FLPA). This approach is based on the separation of the processor architecture into functional blocks like e.g. processing unit, clock network, internal memory and others. The power consumption of these blocks is described by parameter dependent arithmetic model functions. By application of a parser based automized analysis of assembler codes of the systems to be estimated the input parameters of the Correspondence to: H. Blume (blume@eecs.rwth-aachen.de) arithmetic functions like e.g. the achieved degree of parallelism or the kind and number of memory accesses can be computed. This approach is exemplarily demonstrated and evaluated applying two modern digital signal processors and a variety of basic algorithms of digital signal processing. The resulting estimation values for the inspected algorithms are compared to physically measured values. A resulting maximum estimation error of 3% is achieved.

Quantitative methods in electroencephalography to access therapeutic response.

PubMed

Diniz, Roseane Costa; Fontenele, Andrea Martins Melo; Carmo, Luiza Helena Araújo do; Ribeiro, Aurea Celeste da Costa; Sales, Fábio Henrique Silva; Monteiro, Sally Cristina Moutinho; Sousa, Ana Karoline Ferreira de Castro

2016-07-01

Pharmacometrics or Quantitative Pharmacology aims to quantitatively analyze the interaction between drugs and patients whose tripod: pharmacokinetics, pharmacodynamics and disease monitoring to identify variability in drug response. Being the subject of central interest in the training of pharmacists, this work was out with a view to promoting this idea on methods to access the therapeutic response of drugs with central action. This paper discusses quantitative methods (Fast Fourier Transform, Magnitude Square Coherence, Conditional Entropy, Generalised Linear semi-canonical Correlation Analysis, Statistical Parametric Network and Mutual Information Function) used to evaluate the EEG signals obtained after administration regimen of drugs, the main findings and their clinical relevance, pointing it as a contribution to construction of different pharmaceutical practice. Peter Anderer et. al in 2000 showed the effect of 20mg of buspirone in 20 healthy subjects after 1, 2, 4, 6 and 8h after oral ingestion of the drug. The areas of increased power of the theta frequency occurred mainly in the temporo-occipital - parietal region. It has been shown by Sampaio et al., 2007 that the use of bromazepam, which allows the release of GABA (gamma amino butyric acid), an inhibitory neurotransmitter of the central nervous system could theoretically promote dissociation of cortical functional areas, a decrease of functional connectivity, a decrease of cognitive functions by means of smaller coherence (electrophysiological magnitude measured from the EEG by software) values. Ahmad Khodayari-Rostamabad et al. in 2015 talk that such a measure could be a useful clinical tool potentially to assess adverse effects of opioids and hence give rise to treatment guidelines. There was the relation between changes in pain intensity and brain sources (at maximum activity locations) during remifentanil infusion despite its potent analgesic effect. The statement of mathematical and computational aspects in the use of clinical data is frequent and elucidation of these aspects we use PhysioNet https://www.physionet.org/, Clinical Database online supported by the National Institutes of Health (National Institutes of Health of United States of America/NIH-USA) for the acquisition of EEG data and the Matlab program to do the simulations with the methods and thus create opportunities greater understanding. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Komatiites of the Onverwacht Group, S. Africa: REE geochemistry, Sm/Nd age and mantle evolution

NASA Astrophysics Data System (ADS)

Jahn, Bor-Ming; Gruau, G.; Glikson, A. Y.

1982-08-01

Komatiites of the Tjakastad Subgroup of the Onverwacht Group (S. Africa) were dated by the Sm/Nd method. A whole-rock isochron yields an age of 3.56±0.24 (2 σ) AE, with initial 143Nd/144Nd ratio of 0.50818±23 (2 σ), corresponding to ɛ Nd( T)= + 1.9±4.5. This age is interpreted as the time of initial Onverwacht volcanism. This result agrees with earlier Sm/Nd data of Hamilton et al. (1979) and is consistent with the Rb-Sr result of Jahn and Shih (1974). Komatiites may be divided into 3 groups based on the typology of heavy REE distributions (Jahn and Gruau 1981). According to this scheme, the Onverwacht komatiites of the present study belong to two groups: the predominant Group II rocks showing (Gd/Yb)N≃1.4, CaO/Al2O3 = 1.33, Al2O3/TiO2≃10.6; and the subordinate Group III rocks with (Gd/Yb)N<1.0; CaO/Al2O3≃0.6 and A12O3/ TiO2≃40. This contrasting feature is best explained by garnet fractionation within the mantle sources. Younger komatiites (˜2.7 AE) from Finland, Canada, Rhodesia, and Australia have (Gd/Yb)N≃1.0, CaO/ Al2O3<1.1 and Al2O3/TiO2≃21 based on 58 analyses. These ratios are nearly chondritic or of the bulk earth value (Anders 1977). It appears that some late Archean komatiites are different in chemistry from many early Archean komatiites. This may imply that the upper mantle chemistry has evolved through Archean times. However, the age connotation of the chemical parameters, such as CaO/Al2O3, (Gd/Yb)N or Al2O3/TiO2 ratio has not been firmly established. The characteristic “high” CaO/Al2O3 or (Gd/Yb)N ratios in many Onverwacht Group rocks can also be explained as a result of local short-term mantle heterogeneity.

CBP PHASE I CODE INTEGRATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, F.; Brown, K.; Flach, G.

The goal of the Cementitious Barriers Partnership (CBP) is to develop a reasonable and credible set of software tools to predict the structural, hydraulic, and chemical performance of cement barriers used in nuclear applications over extended time frames (greater than 100 years for operating facilities and greater than 1000 years for waste management). The simulation tools will be used to evaluate and predict the behavior of cementitious barriers used in near surface engineered waste disposal systems including waste forms, containment structures, entombments, and environmental remediation. These cementitious materials are exposed to dynamic environmental conditions that cause changes in material propertiesmore » via (i) aging, (ii) chloride attack, (iii) sulfate attack, (iv) carbonation, (v) oxidation, and (vi) primary constituent leaching. A set of state-of-the-art software tools has been selected as a starting point to capture these important aging and degradation phenomena. Integration of existing software developed by the CBP partner organizations was determined to be the quickest method of meeting the CBP goal of providing a computational tool that improves the prediction of the long-term behavior of cementitious materials. These partner codes were selected based on their maturity and ability to address the problems outlined above. The GoldSim Monte Carlo simulation program (GTG 2010a, GTG 2010b) was chosen as the code integration platform (Brown & Flach 2009b). GoldSim (current Version 10.5) is a Windows based graphical object-oriented computer program that provides a flexible environment for model development (Brown & Flach 2009b). The linking of GoldSim to external codes has previously been successfully demonstrated (Eary 2007, Mattie et al. 2007). GoldSim is capable of performing deterministic and probabilistic simulations and of modeling radioactive decay and constituent transport. As part of the CBP project, a general Dynamic Link Library (DLL) interface was developed to link GoldSim with external codes (Smith III et al. 2010). The DLL uses a list of code inputs provided by GoldSim to create an input file for the external application, runs the external code, and returns a list of outputs (read from files created by the external application) back to GoldSim. In this way GoldSim provides: (1) a unified user interface to the applications, (2) the capability of coupling selected codes in a synergistic manner, and (3) the capability of performing probabilistic uncertainty analysis with the codes. GoldSim is made available by the GoldSim Technology Group as a free 'Player' version that allows running but not editing GoldSim models. The player version makes the software readily available to a wider community of users that would wish to use the CBP application but do not have a license for GoldSim.« less

Association of pituitary adenylate cyclase-activating polypeptide with cognitive decline in mild cognitive impairment due to Alzheimer disease.

PubMed

Han, Pengcheng; Caselli, Richard J; Baxter, Leslie; Serrano, Geidy; Yin, Junxiang; Beach, Thomas G; Reiman, Eric M; Shi, Jiong

2015-03-01

There is a deficit of pituitary adenylate cyclase-activating polypeptide (PACAP) in patients with neuropathologically confirmed Alzheimer dementia. However, whether this deficit is associated with the earlier stages of Alzheimer disease (AD) is unknown. This study was conducted to clarify the association between PACAP biomarkers and preclinical, mild cognitive impairment (MCI), and dementia stages of AD in postmortem brain tissue. To examine PACAP and PACAP receptor levels in postmortem brain tissues and cerebrospinal fluid from cognitively and neuropathologically normal control individuals, patients with MCI due to AD (MCI-AD), and individuals with AD; analyze the relationship between PACAP, cognitive, and pathologic features; and propose a model to assess these relationships. We measured PACAP and its receptor (PAC1) levels using enzyme-linked immunoassay. A total of 35 cases were included. All the brain tissue and cerebrospinal fluid samples were selected from Banner Sun Health Research Institute Brain and Body Donation Program. All cognitive test results were in record with the Arizona Alzheimer's Consortium. A comparison of PACAP and PAC1 levels among the healthy controls, MCI-AD, and AD dementia groups, as well as a systematic correlation analysis between PACAP level, cognitive performance, and pathologic severity. The PACAP levels in cerebrospinal fluid, the superior frontal gyrus, and the middle temporal gyrus were inversely related to dementia severity. The PACAP levels in cerebrospinal fluid correlated with the Mattis Dementia Rating Scale score (Pearson r = 0.50; P = .03) and inversely correlated with total amyloid plaques (Pearson r = -0.48; P < .01) and tangles (Pearson r = -0.55; P = .01) in the brain. The PACAP in the superior frontal gyrus and middle temporal gyrus correlated with the Stroop Color-Word Interference Test (Pearson r = 0.58; P < .01) and the Auditory Verbal Learning Test-Total Learning (Pearson r = 0.33; P = .02), respectively. The PACAP in the primary visual cortex did not correlate with the Judgment of Line orientation test (P = .14). Furthermore, the PAC1 level in the superior frontal gyrus showed an upregulation in MCI-AD but not in AD. The pharmacodynamic model of the PACAP-PAC1 interaction best predicted cognitive function in the superior frontal gyrus, but it was less predictive in the middle temporal gyrus and failed to be predictive in the primary visual cortex. Deficits in PACAP are associated with clinical severity in the MCI and dementia stages of AD. Additional studies are needed to clarify the role of PACAP deficits in the predisposition to, pathogenesis of, and treatment of AD.

EDITORIAL: Incoming Editor-in-Chief

NASA Astrophysics Data System (ADS)

Lidström, Suzanne

2012-04-01

When Professor Anders Bárány took over as the Executive Editor of Physica Scripta, in 1986, he talked of his trepidation at having to 'dress himself' in his predecessor's 'editorial coveralls'. At that time, they had been worn by Professor Nils Robert Nilsson, a major figure in the physics community, for almost 20 years. Just one year prior to this, Professor Roger Wäppling had been recruited to the position of Subeditor in conjunction with a decision to expand the number of contributions in the field of condensed matter physics, to turn it into one of the dominant subjects in the broad-based journal. Physica Scripta had already gained a reputation for being a high quality journal with wide coverage of both experimental and theoretical physics. Interestingly, in the mid 1980s, the number of papers submitted had been growing and an impressive 250 submissions per year had been attained, with all of the manuscripts being handled in-house. Not many miles away in the town of Uppsala, a group of English students was stepping off a train on a magnificent snowy day in January to embark on their final year projects. A couple of us enjoyed ourselves so much that we stayed on afterwards as PhD students, thereby encountering the mixed pleasure of studying physics in a second language for the first time. I used to copy the notes down meticulously in Swedish, then try to work backwards with a textbook to improve my language skills. One day, returning from a particularly incomprehensible lecture on solid state physics, I showed my roommates my notes and asked if they could please explain what the lecture had been about: 'I don't know', they replied, 'but this bit is about sheep!' Meanwhile, back at Physica Scripta, the journal continued to flourish: 400 submissions were received in 1996, and the march of progress was well underway. Manuscripts could now be sent in on disks and Physica Scripta was available on the World Wide Web. Roger was appointed to manage the journal and, in his hands, the expansion continued and the transition to electronic production took place. In 2005, an agreement was signed with IOP Publishing and the bustling production work of the in-house team moved abroad to Bristol, leaving just the Editor-in-Chief to man the ship at the Royal Swedish Academy of Sciences. In 2011, however, as Roger prepared to step down, submissions had reached astounding levels as is evident from figure 1: that year, almost 1500 manuscripts were received by Physica Scripta, now acknowledged to be amongst the fastest growing journals in IOP Publishing, when measured in these terms. The year on year increase stands at 20% and, once again, of the extensive range of topics covered, condensed matter physics had been identified as the subject area in most need of attention because the burden of reviewing had become too great for one editor to oversee alone. Thus, when I joined Physica Scripta in January of this year, securing new External Editors for this field was perceived to be the most urgent task. It is, therefore, with the greatest of pleasure that I am able to announce the arrival of two new editors for this section: Professors David Keen and Tapio Rantala. Physica Scripta statistics Figure 1. The annual submissions made to Physica Scripta in recent years have rocketed and the rejection rate (given as a percentage) has increased rapidly. The modest increase in the number of articles accepted (shaded in blue) reflects a deliberate policy to augment the scientific quality. Professor Rantala has been selected by the Finnish Physical Society to replace Professor Matti Manninen, who is stepping down as the Finnish representative on the journal's Editorial Board. Professor Rantala is a prominent theorist and has been engaged in active research in a number of fields. In his early work, he was interested in surface science and molecular physics, however his expertise is predominantly in the domain of solid or materials physics related to semiconductors and certain complex materials. His recent interests have extended his domain of activity towards the field of quantum chemistry as he is now actively engaged in electronic structure theory and its applications, and light-matter interactions, in particular. The other new member of our editorial team, Professor David Keen, comes highly recommended by Professor Stephen Lovesey, a long-standing friend and former colleague, who was, himself, a former condensed matter editor for the journal many years ago. Professor Keen works in structural disorder, typically studying at the boundary between crystalline, amorphous and liquid phases using neutron and x-ray diffraction and atomistic modelling. Three examples of the areas in which he conducts research are 'liquid-like' disorder in superionic crystalline materials, solid-state amorphization transitions and disorder-induced properties, such as unusual negative thermal expansion. Through working at these boundaries, and at the ISIS neutron scattering facility at Rutherford Appleton Laboratory for over 20 years, he has gained wide experience of all areas of structural condensed matter physics, encompassing crystallography and the structure and simulation of liquid and amorphous materials. Professor Keen has been a Guest Editor for a number of special issues of Journal of Physics: Condensed Matter. My thanks are extended to Stephen for his advice and for recommending such an enthusiastic new editor to join us. Until recently, the extensive review process engaged by Physica Scripta involved almost every manuscript being forwarded to several researchers for examination. The volume of material being received at present, however, makes this procedure untenable and undesirable, as it would be unfair on those researchers willing to participate in the peer review process to continue to review articles that are obviously destined for rejection. Thus, as a direct result of the increase in volume, a screening procedure has been implemented whereby manuscripts containing insufficiently novel results or papers deemed to be too specialized to warrant inclusion in a broad-based physics journal are being eliminated by experts working actively in the field and deemed to be well-qualified to make this judgment. All of the manuscripts that pass this preliminary round of selection commence the full peer review process. Nevertheless, as it is unrealistic to expect to recruit expert editors to screen every aspect of all subjects, a few manuscripts are occasionally rejected on the basis of just one particularly unfavourable report. These measures are being implemented, in part, because of an awareness that certain researchers are being asked to engage in reviewing with inappropriate regularity: it is my aim to do my best to protect these researchers from excessive and onerous reviewing. As mentioned briefly above, the extensive variety in the material covered by Physica Scripta makes the support of a considerable number of expert subject editors from a variety of fields a necessity. We still have some fields where the addition of further editors is imperative, so I will be striving to identify these and the gaps in our editorial coverage with a view to building up the service that our experts can provide. This is a matter of some urgency, as it must be achieved before the existing editors start to bow under the strain! A second, but by no means less important, priority is to continue to augment the quality of the scientific publications as a whole. This will be achieved by maintaining the trend of increasingly strict acceptance criteria demonstrated in figure 1, where it can be seen that, although the submissions are increasing rapidly, a tight rein is being kept on the quality: the acceptances will not increase with greater rapidity than the quality allows. In addition to the manuscripts received through the conventional submissions process, our popular Comments articles, in which foremost scientists address different topics of interest in their specialist areas, will be expanded. These articles are comprised of discussion papers presenting a historical overview of a subject or reviewing the present state of knowledge, but they go beyond presenting straightforward facts to consider issues that remain open and controversial results. They are written with the explicit intention of being accessible to researchers with a relevant background who are not active in the field, and form part of our deliberate attempt to make research accessible to a wide audience. Another area targeted for growth is that of the Topical Issues, a select series of peer-reviewed publications that includes the Nobel Symposia, and conferences and workshops of notable interest. For completeness, I would like to mention that the Nobel lectures and biographies are available to download free from the Physica Scripta Web site (http://iopscience.iop.org/1402-4896). I would invite all researchers engaged in teaching potential or actual research students to read these inspirational articles. We take our role as the physics journal of the non-profit-making Royal Swedish Academy of Sciences seriously, and intend to actively pursue the goal of promoting physics and strengthening its influence in society. One step taken to achieve this is that of publicising our most accessible articles and making them freely available to the greatest possible extent. Professor Matti Manninen is leaving us subsequent to his appointment as Rector of the University of Jyväskylä. On behalf of IOP Publishing and Physica Scripta, I would like to mention our gratitude to him for his many years of service. In the same breath, I would like to extend a warm welcome to Professors Keen and Rantala. Last, but not least, the considerable contribution that Professor Roger Wäppling has made to the progress of Physica Scripta must be acknowledged. Brought in to expand the condensed matter section in 1985, and promoted to Editor-in-Chief when Professor Bárány stepped down, Roger has managed to increase the contributions in pretty much every subject area, with mathematical physics and quantum physics now being particularly popular sections. Forget the coveralls, Roger's shoes will be large ones to step into! I would like to conclude on a personal note. I have now known Roger for 25 years; during my student days, to my great jealousy, he travelled incessantly and, in my memories, at least, he was away somewhere exotic and exciting every week. There was one thing, however, that one could always guarantee, which was that Roger would return, pop his head around the door and say 'I think it is time we had a party!' I wish him the very best of luck as he prepares for his retirement, I trust that it will be long and happy. I hope that Roger will continue to don his party shoes and join us on many occasions in the future.

Scatterometry

NASA Astrophysics Data System (ADS)

Stoffelen, Adrianus Cornelis Maria

1996-10-01

Een veelheid aan meteorologische metingen is dagelijks beschikbaar. De meeste van deze waarnemingen bevinden zich echter boven land, en met name windwaarnemingen boven de (Noord Atlantische) oceaan zijn schaars. Bij een westelijke luchtstroming is dit een duidelijke beperking voor de weers- en golfverwachtingen ten behoeve van Nederland. Juist dan is het gevaar voor bijvoorbeeld storm of overstroming het grootst. Ook in het aardse klimaatsysteem speelt de wind aan het oppervlak een grote rol en is de belangrijkste factor voor de aandrijving van de oceaancirculatie. De oceaancirculatie op zijn beurt is cruciaal voor de verschijnselen die samenhangen met bijvoorbeeld El Niño. Dit proefschift gaat over het scatterometer instrument dat vanuit de ruimte, zelfs onder een wolkendek, nauwkeurige en betrouwbare informatie geeft over de wind aan het oceaanoppervlak met een hoge mate van ruimtelijke consistentie. Tijdens de tweede wereldoorlog werden radars aan boord van schepen veelvuldig gebruikt voor de opsporing van vijandige vaartuigen. Hierbij werd vastgesteld dat de detectie slechter werd naarmate de wind aan het zeeoppervlak groter was. Proefondervindelijk was hiermee het principe van een wind scatterometer aangetoond. Al snel ontwikkelde zich dan ook de idee de wind aan het zeeoppervlak te meten met behulp van radar. Vanuit een vliegtuig of een satelliet word dan een microgolfbundel onder een schuine hoek naar het zeeoppervlak gestuurd. De microgolfstraling, met gewoonlijk een golflengte van enkele centimeters, wordt verstrooid aan het ruwe oppervlak, en een klein gedeelte van de uitgezonden puls keert terug naar het detectorgedeelte van de scatterometer. Het fysische fenomeen van belang voor de werking van de scatterometer is de aanwezigheid van zogeheten capillaire gavitatiegolven op het zeeoppervlak. Deze golven hebben een golflengte van enkele centimeters en reageren vrijwel instantaan op de sterkte van de wind. De verstrooiing van microgolven is op zijn beurt weer sterk afhankelijk van de amplitude van de capillaire golven. Bovendien blijken de capillaire golfjes over het algemeen gericht in lijn met de windrichting. Aldus bestaat er een verband tussen de hoeveelheid teruggestrooide energie en de windsterkte en -richting op enige hoogte. Een scatterometer instrument wordt zo ontworpen dat uit diverse metingen van het teruggestrooide vermogen, windsterkte en -richting afgeleid kunnen worden. Deze metingen kunnen dan eenvoudig vergeleken worden met bestaande windgegevens van boeien, schepen en weermodellen ter calibratie en validatie.?SAMENVATTING viii Overzicht In de loop der jaren zijn scatterometer instrumenten aan boord van verscheidene satellieten gelanceerd. De scatterometers op de ERS-1 en ERS-2 ("European Remote-sensing Satellite") hebben de langste staat van dienst en zijn sinds 1991 operationeel. Deze scatterometers (die identiek zijn) hebben ieder drie antennes, waarmee het oceaanoppervlak in drie verschillende richtingen bemeten wordt. Een punt op het aardoppervlak wordt eerst door de naar voren gerichte bundel belicht, dan door de naar opzij gerichte bundel, en als laatste door de naar achteren gerichte bundel. De drie metingen, verder kortweg aangeduid als trits, kunnen tegen elkaar worden uitgezet, hetgeen resulteert in een ruimtelijk (3D) plaatje. Door uitgekiende doorsneden te maken van deze ruimte kan de samenhang van de drie metingen kwalitatief worden bestudeerd. De drie metingen blijken dan inderdaad een sterke samenhang te vertonen die verklaard kan worden uit twee geofysische parameters. De drie metingen liggen namelijk in het algemeen dichtbij een hoornvormig (2D) oppervlak. De lengterichting van de hoorn blijkt voornamelijk te corresponderen met een variërende windsterkte (of ruwheid van de zee), en de kortste omtrek van de hoorn met een variërende windrichting (ofwel oriëntatie van de capillaire golfjes). De karakterisatie en modellering van dit oppervlak heeft geleid tot een aanzienlijke verbetering in de interpretatie van de scatterometer, zoals beschreven is in dit proefschrift. Hierboven is een uiterst simplistisch beeld gegeven van de fysica die van belang is bij de interpretatie van de scatterometer. Het eerste hoofdstuk van dit proefschrift beschrijft in meer detail de fysische modellering van belang bij de interpretatie van de scatterometer metingen. Ten eerste, de topografie van het zeeoppervlak is uitermate gecompliceerd en niet nauwkeurig te beschrijven met eenvoudige mathematische vergelijkingen. De capillaire golven hebben een andere fasesnelheid dan de langere golven en beide hebben hiermee een ingewikkelde dynamische interactie. Bij hogere windsnelheid breken de golven en ontstaan er schuimkoppen, hetgeen de fysische beschrijving verder compliceert. Ten tweede, de interactie van een schuin invallende microgolfbundel met dit gecompliceerde oppervlak is evenmin nauwkeurig te beschrijven. Zowel verstrooiing als reflectie kunnen een rol spelen. Ten derde, over de relatie tussen de amplitude van de capillaire golven en de wind op enige hoogte, laten we veronderstellen 10 m, is in de literatuur niet de overeenstemming tot in het gewenste detail. Bij lage windsnelheid zouden de oppervlaktespanning of variaties in de wind variabiliteit een rol kunnen spelen. Gezien de fysische complexiteit, is het niet verwonderlijk dat voor de interpretatie van scatterometer metingen statistische methoden hun opgang gevonden hebben. Dit proefschrift gaat met name in op deze methoden, en geeft, aan de hand van vijf wetenschappelijke publicaties, een tamelijk volledig beeld van de "state-of-the-art", zoals die bereikt is met de?SAMENVATTING ix ERS scatterometers (ERS-1 vanaf 17 juli 1991 en later ERS-2 vanaf 22 november 1995). Het derde hoofdstuk behandelt de visualisatie van de gemeten tritsen in de 3D meetruimte, de bepaling van de spreiding van de metingen rond het hoornvormige oppervlak, en de schatting van de meest waarschijnlijke "werkelijke" (of ruisvrije) trits bij het hoornvormige oppervlak gegeven de metingen en hun nauwkeurigheid (inversie). De perceptie dat de metingen met grote waarschijnlijkheid dichtbij een hoornvormig oppervlak liggen, vormt essentiële a priori informatie van belang voor de inversie. Een inversieprocedure gestoeld op waarschijnlijkheidstheorie is afgeleid. Verder worden aan de hand van de structuur van het hoornvormige oppervlak indicatoren bepaald, van belang voor de kwaliteitscontrole, instrumentbewaking, en de verdere verwerking van de gegevens. In de appendix wordt een methode besproken die beschrijft hoe, aan de hand van geselecteerde windgegevens en een goed wind-microgolf verband, ofwel transfer functie, de scatterometer verstrooiingsmetingen gecalibreerd kunnen worden boven de oceaan. Het blijkt dat deze calibratie, die per antenne wordt uitgevoerd, uiterst nauwkeurig is, en, wanneer toegepast, in de 3D meetruimte de verdeling van gemeten tritsen gemiddeld dichterbij de door de transfer functie gemodelleerde hoorn brengt. Dit levert een verbetert scatterometer wind product op. De methode was met name van groot belang voor de validatie en calibratie van de ERS-2 scatterometer, voordat de instrumentele calibratie was voltooid. Met behulp van een set windgegevens uit een weermodel en hun geschatte nauwkeurigheden, passend in locatie en tijd bij een set van scatterometer metingen en hun geschatte nauwkeurigheden, kan met quasi-lineaire schattingstheorie ("Maximum Likelihood Estimation") de meest waarschijnlijke wind-microgolf transfer functie worden afgeleid. De niet-lineariteit en onnauwkeurige formulering van de transfer functie, een niet-uniforme verdeling van invoergegevens, en een inaccurate formulering van de geschatte nauwkeurigheid kunnen hier een goed resultaat in de weg staan. Een nieuwe functie, genoemd CMOD4, wordt afgeleid in hoofdstuk IV. Een eerste eis die gesteld wordt aan een transfer functie, is dat het in de 3D meetruimte nauwkeurig bij de gemeten tritsen past. Wanneer de "fit" optimaal is zal het gecombineerde effect van meetonnauwkeurigheid en inversiefout kleiner zijn dan 0.5 m s -1 in de wind vector. CMOD4 blijkt binnen deze fout bij de metingen te passen. Een tweede eis is, dat voor een onafhankelijke gegevensset, het verschil tussen de geïnverteerde scatterometer wind en de bijpassende wind van bijvoorbeeld een weermodel zo klein mogelijk is. In de praktijk blijkt dat deze tweede eis impliciet volgt uit de eerste, maar ook dat de onnauwkeurigheid van de scatterometer wind met name wordt bepaald door de associatie van een locatie op de hoorn met een wind vector. De onnauwkeurigheid in de scatterometer wind kan dan ook goed beschreven worden in het wind domein.?SAMENVATTING x In hoofdstuk V wordt dit laatste verder uitgewerkt, en wordt gestreefd naar een gedetailleerde wind calibratie met behulp van in situ gegevens. Windgegevens bevatten doorgaans een relatief grote onnauwkeurigheid. Het wordt aangetoond dat ijking of regressie van zulke gegevens niet mogelijk is in een vergelijking van twee meetsystemen, tenzij de nauwkeurigheid van één van de twee meetsystemen bekend is. In de praktijk is dit meestal niet zo. Voor deze gevallen wordt een methode voorgesteld die uitgaat van de simultane vergelijking van drie meetsystemen. In dit geval kan zowel de ijking als een foutenmodel voor de drie meetsystemen worden opgelost. Toepassing van de methode laat zien dat de scatterometer wind afgeleid met behulp van CMOD4 ruwweg 5 % te laag is, en de oppervlaktewind van het gebruikte weermodel ongeveer 5 % te hoog. Het hoornvormige oppervlak blijkt te bestaan uit twee nauw samenvallende laagjes. Wanneer de wind een component heeft in de kijkrichting van de middelste microgolfbundel wordt de ene hoorn beschreven, en wanneer de wind een component heeft tegengesteld hieraan, de andere. Uit een trits metingen (met ruis) kan dus in het algemeen niet een unieke windvector worden bepaald. Twee ongeveer tegengestelde oplossingen resulteren. Deze dubbelzinnigheid in de windrichting kan in de praktijk worden opgelost door die oplossing te kiezen die het dichtst bij een korte termijn weervoorspelling ligt. Daarna kunnen eisen worden gesteld aan de ruimtelijke consistentie van het gevonden windvector veld. Zoals beschreven in hoofdstuk V levert zo'n methode de goede oplossing in meer dan 99 % van de gevallen. Zo kan een in het algemeen kwalitatief goed windproduct worden afgeleid uit de ERS scatterometermetingen. In het tweede gedeelte van hoofdstuk V wordt ingegaan op de assimilatie van scatterometergegevens in weermodellen. Voor variationele gegevensassimilatie wordt een methode voorgesteld, waarbij de dubbelzinnige scatterometerwinden worden geassimileerd, en niet direct de terugstrooiingsmetingen. Dit vanwege het feit dat de onzekerheid in de interpretatie van de scatterometer, het best is uit te drukken als een fout in de wind. De projectie van deze fout op de microgolfmetingen is niet-lineair, en daarmee tamelijk moeilijk te verwerken binnen de context van meteorologische variationele gegevensassimilatie. Assimilatie van de dubbelzinnige wind daarentegen is tamelijk recht toe recht aan. De scatterometermetingen leiden tot een duidelijk betere analyse en korte-termijn voorspelling van het windveld boven zee. De bedekking is echter zodanig dat andere windwaarnemingen nog lang een zeer welkome aanvulling zullen zijn. Nieuwe Amerikaanse scatterometers met een grotere bedekking zijn in ontwikkeling (met name QuikSCAT en SeaWinds). Vanwege hun andere geometrie en golflengte is echter eerst ontwikkelwerk nodig om tot een gedegen interpretatie te komen. De in dit proefschrift beschreven methodologie kan een belangrijke rol spelen in de interpretatie van de gegevens van deze scatterometers. De volgende generatie Europese scatterometers (ASCAT genoemd) heeft een?SAMENVATTING xi grote bedekking en de microgolflengte en meetgeometrie van de ERS scatterometers. Hiermee zijn we op termijn verzekerd van een goed scatterometer wind product.?SAMENVATTING xii

The COCCON Paris Experiment - Model-Data Comparison of XCO2 (and XCH4) in an Urban Environment

NASA Astrophysics Data System (ADS)

Vogel, F. R.; Staufer, J.; Frey, M.; Broquet, G.; Xueref-Remy, I.; Sha, M. K.; Blumenstock, T.; Te, Y. V.; Janssen, C.; Jeseck, P.; Chelin, P.; Fratacci, T.; Tu, Q.; Gross, J.; Schäfer, K.; Orphal, J.; Ciais, P.; Hase, F.

2016-12-01

Currently, over 50% of the global population lives in urban areas1 and the future population growth is also predicted to occur mostly in urban centers. While emissions of Greenhouse Gases and carbon-based air pollutants can be estimated quite precisely on national scale using fuel consumption statistics, typically to about 3%-40%2, higher uncertainties of 20%-50% are reported3 for urban GHG emissions. Atmospheric observations, when combined with inversion modelling can allow independently assessing such urban emission inventories4. This study investigates how well novel low-resolution FTS observations can be represented within atmospheric transport models used in such inversion systems, which would be the pre-requisite for a future system based on XCO2 observations. A network of five EM27sun instruments5,6was deployed across the Paris Metropolitan region (upwind, downwind and inside of Paris, diameter ca. 40km) for a three week period in spring 2015. Observed XCO2 significantly varies during this period ranging from 400.5ppm to 406ppm. A decrease in XCO2 throughout the day, likely driven by the biogenic CO2 uptake in the region, is recorded at all sites. Both observational and simulated XCO2 also clearly show that the emissions in the Paris region significantly increase XCO2 (0-2ppm), depending on meteorological conditions. The observational data is compared to three configurations of our XCO2 forward model to assess their performance. We find that all simulations and observations agree qualitatively and that the gradient of XCO2 over Paris can also be reproduced quantitatively for specific meteorological conditions and optimal model setup. 1United Nations, Department of Economic and Social Affairs, Population Division (2014). World Urbanization Prospects: The 2014 Revision 2Anders et al. 2014, Tellus B 2014, 66, 23616, http://dx.doi.org/10.3402/tellusb.v66.23616 3Wu et al. 2016, Atmos. Chem. Phys., 16, 7743-7771, doi:10.5194/acp-16-7743-2016 4Staufer et al. 2016, Atmos. Chem. Phys. Diss., under review for ACP, doi:10.5194/acp-2016-191 5Gisi et al., Atmos. Meas. Tech., 5, 2969-2980, doi:10.5194/amt-5-2969-2012, 2012 6Hase et al. 2015, Atmos. Meas. Tech., 8, 3047-3057, doi :10.5194/amt-8-3047-2015

The Orgueil meteorite: 150 years of history

NASA Astrophysics Data System (ADS)

Gounelle, Matthieu; Zolensky, Michael E.

2014-10-01

The goal of this paper is to summarize 150 yr of history of a very special meteorite. The Orgueil meteorite fell near Montauban in southwestern France on May 14, 1864. The bolide, which was the size of the full Moon, was seen across Western France, and almost immediately made the news in local and Parisian newspapers. Within a few weeks of the fall, a great diversity of analyses were performed under the authority of Gabriel Auguste Daubrée, geology professor at the Paris Museum, and published in the Comptes Rendus de l'Académie des Sciences. The skilled scientists reported the presence of iron sulfides, hydrated silicates, and carbonates in Orgueil. They also characterized ammonium salts which are now gone, and observed sulfates being remobilized at the surface of the stone. They identified the high water and carbon contents, and noted similarities with the Alais meteorite, which had fallen in 1806, 300 km away. While Daubrée and his colleagues noted the similarity of the Orgueil organic matter with some terrestrial humus, they were cautious not to make a direct link with living organisms. One century later, Nagy and Claus were less prudent and announced the discovery of "organized" elements in some samples of Orgueil. Their observations were quickly discredited by Edward Anders and others who also discovered that some pollen grains were intentionally placed into the rock back in the 1860s. Orgueil is now one of the most studied meteorites, indeed one of the most studied rocks of any kind. Not only does it contain a large diversity of carbon-rich compounds, which help address the question of organo-synthesis in the early solar system but its chemical composition is also close to that of the Sun's photosphere and serves as a cosmic reference. Secondary minerals, which make up 99% of the volume of Orgueil, were probably formed during hydrothermal alteration on the parent-body within the first few million years of the solar system; their study is essential to our understanding of fluid-rock interaction in asteroids and comets. Finally, the Orgueil meteorite probably originated from a volatile-rich "cometary" outer solar system body as indicated by its orbit. Because it bears strong similarities to other carbonaceous chondrites that originated on dark asteroids, this cometary connection supports the idea of a continuum between dark asteroids and comets.

The Preservation of Cometary Organics in Stardust Aerogel

NASA Astrophysics Data System (ADS)

Clemett, Simon; Nakamura-Messenger, Keiko; Sandford, Scott; McKay, David

It has been recognized for many years that the continuous global accretion of organic matter from comets and carbonaceous asteroids, over geological timescales, to the surfaces of both Earth and Mars may have played a significant role in the prebiotic chemical evolution of these planets [1]. The dominant mass fraction of accreted meteoritic material is in the form of interplanetary dust for which the current accretion rate is estimated at ˜ 40±20 Gg·yr-1 [2]. Our understanding of the organic matter present in interplanetary dust is, however, limited by the analytical challenges involved in the molecular analysis of heterogeneous micron sized particles. We have used the technique of ultrafast two-step laser mass spectrometry (µltra-L2 MS) to investigate the nature and distribution of the aromatic organic matter present in individual dust particles from comet P81/Wild 2 collected in aerogel by the STARDUST sample return mission [3]. Complex aromatic hydrocarbons have been detected in cometary particles entrained along multiple aerogel tracks. Although terrestrial contamination from the aerogel remains a concern, a substantial fraction is interpreted as indigenous. The spectral complexity is atypical of carbonaceous and ordinary chondrites. While simple fused ring polycyclic aromatic hydrocarbon (PAHs) such as naphthalene (C10 H8 ), acenaphthalene (C12 H8 ), phenanthrene (C14 H10 ) are present along with their homologous alkylation series (Ar-(CH2 )n -H) there are additionally many prominent odd-mass species present. These are consistent with several interleaved alkylation series of N-containing PAHS (NPAHs) in the form of nitriles (Ar-CN). These species may be related to the 2.3 & 4.6 µm 'XCN' adsorption features observed in the spectra of many young stellar objects and some comets, which is believed to be synthesized by ultraviolet and/or ion bombardment of precometary ices in circumstellar environments. The presence of organo-N species is of particular importance to the organic inventory of the the early Earth since its abiotic synthesis would have been extremely slow due to the difficulty in cleaving the N≡N triple bond in the absence of biology. [1] Anders (1989) Nature 342, 255; [2] Love & Brownlee (1993) Science 262, 550; Clemett et al. MAPS (submited)

The Dala (Älvdalen) Porphyries from Sweden

NASA Astrophysics Data System (ADS)

Wikström, Anders; Pereira, Lola; Lundqvist, Thomas; Cooper, Barry

2014-05-01

The Dala (Älvdalen) Porphyries from Sweden Anders Wikström (retired from Geological Survey of Sweden) Lola Pereira (University of Salamanca, Spain) Thomas Lundqvist (retired from Geological Survey of Sweden) Barry Cooper (University of South Australia) The commercial stone industry in Älvdalen, about 350 km northwest of Stockholm, commenced in the second half of the 18th century, as a consequence of social need. The region had been plagued by severe famine and there was an urgent need for additional wealth-generating industry. At that time it was already known that the porphyry in the area was similar to the "porfido rosso antico" from Egypt which had played an important role in the Roman culture. Many ups and downs followed. During one period in the 19th century, the Swedish Royal family owned the industry. At the same time, several "porphyry" objects were presented to different courts around Europe (e.g. a 4 metre tall vase to the Russian czar, although of a more granitic variety). Otherwise most products have been smaller objects like urns, vases, candelabras, etc. The very hard stone (with variable red or black colours) can be highly polished. Many of the porphyry varieties were sourced from glacial boulders. These had been "mechanically tested" by nature and were free from joints which otherwise was a problem in the associated quarries. Comagmatic granites also occur. The porphyries and granites have an age around 1700 Ma, and the former are amazingly well preserved with magnificent volcanic textures. The porphyries and granites occupy a vast area and are in part covered with red, continental sandstones (which are quarried to-day). In the middle of the 20th century, the ignimbritic character of the porphyry was discovered. Previously, the flattened "fiamme" (collapsed pumice) had been interpreted as some kind of flow structure in a lava. The porphyry manufacturing plants in Älvdalen are a part of the Swedish industrial history. Over a significant historical period the porphyry-works produced good handicrafts that catered for the poor as well as providing items of extravagant luxury. To-day a porphyry museum exists in Älvdalen. A few handicraft workers are active , and the abandoned old porphyry plants are open to visitors.

Teacher and student actions to construct biology literacy at a community college: A bounded case study

NASA Astrophysics Data System (ADS)

Griesel, Patricia

2000-10-01

Science content area literacy, particularly literacy development in college level biology, is the focus of this study. The study investigates the actions and activities of an instructor and six students over the course of 16 weeks. The study is in response to interest in the literate practices in science classes (NSES, 1996) and to the call for contextual studies that facilitate the learning of science (Borasi & Siegel, 1999; Moje, 1996; Nist & Holschuh, 1996; Prentiss, 1998). A collaborative study between the biology teacher and the researcher, this study investigates the practices believed to be effective for the development of biology literacy. Data sources, in the qualitative bounded case study (Bogdin & Biklin, 1982; Glaser & Strauss, 1967; Miles & Huberman, 1994), include: field notes of classroom observations, in-depth interviews (Seidman, 1992), class surveys, and literate artifacts. The data were coded and analyzed using a constant comparative method (Glaser & Strauss, 1967). The six students reveal similarities and differences regarding the actions, patterns, practices and use of materials and their beliefs about effective practice in the development of biology literacy. The results indicate that a variety of actions and activities are needed to facilitate the development of biology literacy. The common themes to develop from the students' data about effective teacher actions are the following: (a) involves and engages students in inquiry learning through group projects, hands-on, and group discussions; (b) relates examples, experiences, and stories; (c) exhibits expertise; (d) encourages a relaxed classroom atmosphere; (e) facilitates and coaches students; and (f) credits creativity. Further, students report their teacher to be an expert, in terms of science knowledge and literate practices, and that her expertise contributes to their understanding of biology literacy. The teachers' data reveals three themes embedded in her classroom actions: science as a language, science as a social activity, and science as an experiential activity. The researcher's role in the study suggests that other researchers may benefit from a similar collaborative effort where the teacher and researcher learn from each other and from their students while supporting content literacy development. Content literacy practice from a constructivist paradigm (Anders & Guzzetti, 1996; Staver, 1998) has merit beyond high school and powerful implications for practice at the college level.

Neuropsychological and psychiatric changes after deep brain stimulation for Parkinson's disease: a randomised, multicentre study.

PubMed

Witt, Karsten; Daniels, Christine; Reiff, Julia; Krack, Paul; Volkmann, Jens; Pinsker, Markus O; Krause, Martin; Tronnier, Volker; Kloss, Manja; Schnitzler, Alfons; Wojtecki, Lars; Bötzel, Kai; Danek, Adrian; Hilker, Rüdiger; Sturm, Volker; Kupsch, Andreas; Karner, Elfriede; Deuschl, Günther

2008-07-01

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) reduces motor symptoms in patients with Parkinson's disease (PD) and improves their quality of life; however, the effect of DBS on cognitive functions and its psychiatric side-effects are still controversial. To assess the neuropsychiatric consequences of DBS in patients with PD we did an ancillary protocol as part of a randomised study that compared DBS with the best medical treatment. 156 patients with advanced Parkinson's disease and motor fluctuations were randomly assigned to have DBS of the STN or the best medical treatment for PD according to the German Society of Neurology guidelines. 123 patients had neuropsychological and psychiatric examinations to assess the changes between baseline and after 6 months. The primary outcome was the comparison of the effect of DBS with the best medical treatment on overall cognitive functioning (Mattis dementia rating scale). Secondary outcomes were the effects on executive function, depression, anxiety, psychiatric status, manic symptoms, and quality of life. Analysis was per protocol. The study is registered at ClinicalTrials.gov, number NCT00196911. 60 patients were randomly assigned to receive STN-DBS and 63 patients to have best medical treatment. After 6 months, impairments were seen in executive function (difference of changes [DBS-best medical treatment] in verbal fluency [semantic] -4.50 points, 95% CI -8.07 to -0.93, Cohen's d=-;0.4; verbal fluency [phonemic] -3.06 points, -5.50 to -0.62, -0.5; Stroop 2 naming colour error rate -0.37 points, -0.73 to 0.00, -0.4; Stroop 3 word reading time -5.17 s, -8.82 to -1.52, -0.5; Stroop 4 colour naming time -13.00 s, -25.12 to -0.89, -0.4), irrespective of the improvement in quality of life (difference of changes in PDQ-39 10.16 points, 5.45 to 14.87, 0.6; SF-36 physical 16.55 points, 10.89 to 22.21, 0.9; SF-36 psychological 9.74 points, 2.18 to 17.29, 0.5). Anxiety was reduced in the DBS group compared with the medication group (difference of changes in Beck anxiety inventory 10.43 points, 6.08 to 14.78, 0.8). Ten patients in the DBS group and eight patients in the best medical treatment group had severe psychiatric adverse events. DBS of the STN does not reduce overall cognition or affectivity, although there is a selective decrease in frontal cognitive functions and an improvement in anxiety in patients after the treatment. These changes do not affect improvements in quality of life. DBS of the STN is safe with respect to neuropsychological and psychiatric effects in carefully selected patients during a 6-month follow-up period. German Federal Ministry of Education and Research (01GI0201).

Integrating geology and geomorphology; the key to unlocking Quaternary tectonic framework of the San Andreas Fault zone in the San Gorgonio Pass region, southern California

NASA Astrophysics Data System (ADS)

Kendrick, K. J.; Matti, J. C.

2012-12-01

The San Gorgonio Pass (SGP) region of southern California is a locus of long-continued Quaternary deformation and landscape evolution within a structural complexity, colloquially referred to as a knot in the San Andreas Fault (SAF) zone. The geomorphology of the SGP region reflects the complex history of geologic events involved in the formation and resolution of this structural knot. We recognize five morphologically distinct terrains in and around SGP; the San Gorgonio Block (SGB), Yucaipa Ridge (YRB), Pisgah Peak (PPB), Kitching Peak (KPB), and Devil's Garden blocks (DGB). Morphometric analyses, including drainage density, hypsometry, topographic profiles, and stream-power measurements and discontinuities, consistently demonstrate distinctions between the blocks. Our focus in this study is on the KPB and PPB terrains, both developed in crystalline rocks of San Gabriel Mountains type. KPB is bounded on the north by the Mission Creek strand of the SAF and on the east by the Whitewater Fault; PPB is bounded on the north by the San Bernardino strand of the SAF, which continues southeastward into the core of SGP and there separates PPB from KPB. KPB has significantly greater topographic relief than PPB, and the two blocks have internal morphometric and geologic characteristics that differ significantly. Canyons in KPB lack thick Quaternary alluvial fills, and hillslopes have shed numerous bedrock landslides. Canyons in PPB contain large volumes of Middle-Pleistocene through Holocene alluvium, associated with areally extensive relict geomorphic surfaces. We use the geomorphic differences, along with geologic factors, to reconstruct tectonically driven landscape evolution over the last 100-200 Ka years. The KPB and PPB both are bounded southward by contractional structures of the San Gorgonio Pass Fault zone (SGPFZ), but geologic complexity within this zone differs markedly south of each block. South of KPB, the SGPFZ consists of multiple thrust-fault strands, some older than 500 ka, has a wide spatial footprint along a N-S axis, and Holocene alluvium is disrupted by numerous fault scarps. By contrast, south of PPB the SGPFZ consists of fewer thrust-fault strands, has a relatively narrow footprint, and faults breaking Holocene deposits are uncommon. The San Bernardino strand of the SAF intersects the SGPFZ at about the boundary between these two domains. Morphometric data indicate that the KPB has undergone significantly greater uplift than the PPB since inception of the San Bernardino strand, proposed by Matti and Morton (1993) to have occurred at ~125ka. Age estimates associated with the PPB and DGB allow us to broadly estimate relative uplift rates. Drainage reconstruction of the Whitewater River and its tributaries across the YRB likewise allow us to validate and refine the uplift estimated by Spotila and others (2001). YRB has been uplifted relative to SGB since the inception of the Mill Creek Strand of the SAF.

Seeing Is Believing. Or Is It?

NASA Astrophysics Data System (ADS)

Moore, John W.

1999-08-01

Occasionally I get time to read something other than a scientific journal, book, or manuscript. On one such foray I discovered Kenneth Brower's "Photography in the Age of Falsification", which appeared in The Atlantic Monthly in May 1998. Brower described how an editor, who might never have experienced the wildness of nature, could conceive a photograph and assign a photographer to create it. Whether the scene depicted was actually possible often seemed relatively unimportant. The main thing was whether the image would interest viewers. Brower argued that today's vast array of software for manipulating digital versions of photographic images enables what he calls "photofakery" on an unprecedented scale. He described how editors at National Geographic decided to pull an ad that depicted a polar bear in Antarctica (where there are no bears); the ad had been created by digitally superimposing a photograph of a bear in a Cincinnati zoo and a photograph of the Lemaire Channel in Antarctica. According to Brower, "Too few photographers, I think, appreciate how directly the new technology aims at the heart of the credibility that distinguishes this art form from others." Credibility is also one of the hallmarks of science. Science progresses as a result of consensus on what results can be expected from carefully designed and carefully executed experiments and observations. As teachers of chemistry, we have a duty not to fall into the same kinds of traps that have made some photographers uneasy about their profession. And we need to help our students learn to avoid these traps. But it is not that easy, because we also need to capture students' attention and try to make our subject interesting by telling stories or showing phenomena or models that appeal to the imagination. As in the case of photography, defining where imagination begins to usurp reality is difficult. It is therefore a very important issue to wrestle with. Part of Brower's argument against manipulation of images centered on the photograph reproduced here. In 1968, when it was taken by Colonel William Anders of Apollo 8, it galvanized the public's understanding of earth's limited resources by showing an astronaut's view of the isolation and beauty of the earth in a barren cosmos. Brower and others characterize it as "the most important photograph in the history of environmental awareness." The photograph is striking and has not been "enhanced". Anders simply pointed the camera and tripped the shutter, and the result was an excellent representation of what he saw. It supported his description of his experience and helped him to make it known to the vast majority of us who will never make a trip to the moon. Many of our students and most of the general public are unlikely to penetrate very deeply into the world of chemistry. They are often placed in a position described eloquently by the Dalai Lama, who was asked by a group of scientists whether he accepted the existence of phenomena he had not experienced. He said, "I know the earth to be a round, bluish globe by relying on the words of someone who has seen it and proved it with photographs. You have to rely on a person who has already had this kind of experience and has no reason to tell lies." Having no reason to tell lies certainly ought to characterize scientists and those of us who teach the subject, as should Brower's quotation of Rusty Schweickart, on one of the roles of astronauts: "You are the sensing element for humanity, and that becomes a rather special responsibility." Indeed scientists and science educators do have a special responsibility, both in discovering new science and in relating the joy and importance of such discoveries to many other people. In doing so, we should be very careful to maintain the credibility without which communication of science becomes impossible. This requires that we have standards that we all agree to follow. As I watch television programs in which there are seamless transitions from photographs or videos of real things to artists' animated conceptions of things that might be, I wonder whether our standards are sufficiently high. The artists' conceptions are seldom labeled as what they are. How is a viewer to tell the difference-especially if that viewer has obtained most of his or her information about science through this same vicarious medium? This current situation argues strongly for incorporation of real, hands-on involvement of students with science throughout formal schooling. Concentrating on observation and manipulation of materials is likely to be more productive than introducing theories and nanoscale models. As someone old enough to have gotten through elementary school before there was a television set at home, I marvel at the vast array of distractions that separate today's children from real phenomena. Videos, computers, theme parks, the Internet, and various other forms of entertainment are so prevalent that we ought to think very carefully about what kinds of real experiences students have had before they arrive in our classes. It may be that laboratory instruction that expands students' exposure to a range of real, tangible experiences and observations is by far the most important aspect of our courses. Certainly we should pay lots more attention to helping students learn to distinguish observation from explanation, fact from theory, and reality from mental model.

Editorial: Focus on X-ray Beams with High Coherence

NASA Astrophysics Data System (ADS)

Robinson, Ian; Gruebel, Gerhard; Mochrie, Simon

2010-03-01

This editorial serves as the preface to a special issue of New Journal of Physics, which collects together solicited papers on a common subject, x-ray beams with high coherence. We summarize the issue's content, and explain why there is so much current interest both in the sources themselves and in the applications to the study of the structure of matter and its fluctuations (both spontaneous and driven). As this collection demonstrates, the field brings together accelerator physics in the design of new sources, particle physics in the design of detectors, and chemical and materials scientists who make use of the coherent beams produced. Focus on X-ray Beams with High Coherence Contents Femtosecond pulse x-ray imaging with a large field of view B Pfau, C M Günther, S Schaffert, R Mitzner, B Siemer, S Roling, H Zacharias, O Kutz, I Rudolph, R Treusch and S Eisebitt The FERMI@Elettra free-electron-laser source for coherent x-ray physics: photon properties, beam transport system and applications E Allaria, C Callegari, D Cocco, W M Fawley, M Kiskinova, C Masciovecchio and F Parmigiani Beyond simple exponential correlation functions and equilibrium dynamics in x-ray photon correlation spectroscopy Anders Madsen, Robert L Leheny, Hongyu Guo, Michael Sprung and Orsolya Czakkel The Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS) Sébastien Boutet and Garth J Williams Dynamics and rheology under continuous shear flow studied by x-ray photon correlation spectroscopy Andrei Fluerasu, Pawel Kwasniewski, Chiara Caronna, Fanny Destremaut, Jean-Baptiste Salmon and Anders Madsen Exploration of crystal strains using coherent x-ray diffraction Wonsuk Cha, Sanghoon Song, Nak Cheon Jeong, Ross Harder, Kyung Byung Yoon, Ian K Robinson and Hyunjung Kim Coherence properties of the European XFEL G Geloni, E Saldin, L Samoylova, E Schneidmiller, H Sinn, Th Tschentscher and M Yurkov Fresnel coherent diffractive imaging: treatment and analysis of data G J Williams, H M Quiney, A G Peele and K A Nugent Imaging of complex density in silver nanocubes by coherent x-ray diffraction R Harder, M Liang, Y Sun, Y Xia and I K Robinson Methodology for studying strain inhomogeneities in polycrystalline thin films during in situ thermal loading using coherent x-ray diffraction N Vaxelaire, H Proudhon, S Labat, C Kirchlechner, J Keckes, V Jacques, S Ravy, S Forest and O Thomas Ptychographic coherent diffractive imaging of weakly scattering specimens Martin Dierolf, Pierre Thibault, Andreas Menzel, Cameron M Kewish, Konstantins Jefimovs, Ilme Schlichting, Konstanze von König, Oliver Bunk and Franz Pfeiffer Dose requirements for resolving a given feature in an object by coherent x-ray diffraction imaging Andreas Schropp and Christian G Schroer FLASH: new opportunities for (time-resolved) coherent imaging of nanostructures R Treusch and J Feldhaus Structure of a single particle from scattering by many particles randomly oriented about an axis: toward structure solution without crystallization? D K Saldin, V L Shneerson, M R Howells, S Marchesini, H N Chapman, M Bogan, D Shapiro, R A Kirian, U Weierstall, K E Schmidt and J C H Spence Analysis of strain and stacking faults in single nanowires using Bragg coherent diffraction imaging V Favre-Nicolin, F Mastropietro, J Eymery, D Camacho, Y M Niquet, B M Borg, M E Messing, L-E Wernersson, R E Algra, E P A M Bakkers, T H Metzger, R Harder and I K Robinson Coherent science at the SwissFEL x-ray laser B D Patterson, R Abela, H-H Braun, U Flechsig, R Ganter, Y Kim, E Kirk, A Oppelt, M Pedrozzi, S Reiche, L Rivkin, Th Schmidt, B Schmitt, V N Strocov, S Tsujino and A F Wrulich Energy recovery linac (ERL) coherent hard x-ray sources Donald H Bilderback, Joel D Brock, Darren S Dale, Kenneth D Finkelstein, Mark A Pfeifer and Sol M Gruner Statistical and coherence properties of radiation from x-ray free-electron lasers E L Saldin, E A Schneidmiller and M V Yurkov Microscopic return point memory in Co/Pd multilayer films K A Seu, R Su, S Roy, D Parks, E Shipton, E E Fullerton and S D Kevan Holographic and diffractive x-ray imaging using waveguides as quasi-point sources K Giewekemeyer, H Neubauer, S Kalbfleisch, S P Krüger and T Salditt Mapping the conformations of biological assemblies P Schwander, R Fung, G N Phillips Jr and A Ourmazd Imaging the displacement field within epitaxial nanostructures by coherent diffraction: a feasibility study Ana Diaz, Virginie Chamard, Cristian Mocuta, Rogerio Magalhães-Paniago, Julian Stangl, Dina Carbone, Till H Metzger and Günther Bauer The potential for two-dimensional crystallography of membrane proteins at future x-ray free-electron laser sources Cameron M Kewish, Pierre Thibault, Oliver Bunk and Franz Pfeiffer Coherence properties of hard x-ray synchrotron sources and x-ray free-electron lasers I A Vartanyants and A Singer Coherent imaging of biological samples with femtosecond pulses at the free-electron laser FLASH A P Mancuso, Th Gorniak, F Staier, O M Yefanov, R Barth, C Christophis, B Reime, J Gulden, A Singer, M E Pettit, Th Nisius, Th Wilhein, C Gutt, G Grübel, N Guerassimova, R Treusch, J Feldhaus, S Eisebitt, E Weckert, M Grunze, A Rosenhahn and I A Vartanyants

Costs and Efficiency of Online and Offline Recruitment Methods: A Web-Based Cohort Study.

PubMed

Christensen, Tina; Riis, Anders H; Hatch, Elizabeth E; Wise, Lauren A; Nielsen, Marie G; Rothman, Kenneth J; Toft Sørensen, Henrik; Mikkelsen, Ellen M

2017-03-01

The Internet is widely used to conduct research studies on health issues. Many different methods are used to recruit participants for such studies, but little is known about how various recruitment methods compare in terms of efficiency and costs. The aim of our study was to compare online and offline recruitment methods for Internet-based studies in terms of efficiency (number of recruited participants) and costs per participant. We employed several online and offline recruitment methods to enroll 18- to 45-year-old women in an Internet-based Danish prospective cohort study on fertility. Offline methods included press releases, posters, and flyers. Online methods comprised advertisements placed on five different websites, including Facebook and Netdoktor.dk. We defined seven categories of mutually exclusive recruitment methods and used electronic tracking via unique Uniform Resource Locator (URL) and self-reported data to identify the recruitment method for each participant. For each method, we calculated the average cost per participant and efficiency, that is, the total number of recruited participants. We recruited 8252 study participants. Of these, 534 were excluded as they could not be assigned to a specific recruitment method. The final study population included 7724 participants, of whom 803 (10.4%) were recruited by offline methods, 3985 (51.6%) by online methods, 2382 (30.8%) by online methods not initiated by us, and 554 (7.2%) by other methods. Overall, the average cost per participant was €6.22 for online methods initiated by us versus €9.06 for offline methods. Costs per participant ranged from €2.74 to €105.53 for online methods and from €0 to €67.50 for offline methods. Lowest average costs per participant were for those recruited from Netdoktor.dk (€2.99) and from Facebook (€3.44). In our Internet-based cohort study, online recruitment methods were superior to offline methods in terms of efficiency (total number of participants enrolled). The average cost per recruited participant was also lower for online than for offline methods, although costs varied greatly among both online and offline recruitment methods. We observed a decrease in the efficiency of some online recruitment methods over time, suggesting that it may be optimal to adopt multiple online methods. ©Tina Christensen, Anders H Riis, Elizabeth E Hatch, Lauren A Wise, Marie G Nielsen, Kenneth J Rothman, Henrik Toft Sørensen, Ellen M Mikkelsen. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 01.03.2017.

Flight Dynamics Performances of the MetOp A Satellite during the First Months of Operations

NASA Technical Reports Server (NTRS)

Righetti, Pier Luigi; Meixner, Hilda; Sancho, Francisco; Damiano, Antimo; Lazaro, David

2007-01-01

The 19th of October 2006 at 16:28 UTC the first MetOp satellite (MetOp A) was successfully launched from the Baykonur cosmodrome by a Soyuz/Fregat launcher. After only three days of LEOP operations, performed by ESOC, the satellite was handed over to EUMETSAT, who is since then taking care of all satellite operations. MetOp A is the first European operational satellite for meteorology flying in a Low Earth Orbit (LEO), all previous satellites operated by EUMETSAT, belonging to the METEOSAT family, being located in the Geo-stationary orbit. To ensure safe operations for a LEO satellite accurate and continuous commanding from ground of the on-board AOCS is required. That makes the operational transition at the end of the LEOP quite challenging, as the continuity of the Flight Dynamics operations is to be maintained. That means that the main functions of the Flight Dynamics have to be fully validated on-flight during the LEOP, before taking over the operational responsibility on the spacecraft, and continuously monitored during the entire mission. Due to the nature of a meteorological operational mission, very stringent requirements in terms of overall service availability (99 % of the collected data), timeliness of processing of the observation data (3 hours after sensing) and accuracy of the geo-location of the meteorological products (1 km) are to be fulfilled. That translates in tight requirements imposed to the Flight Dynamics facility (FDF) in terms of accuracy, timeliness and availability of the generated orbit and clock solutions; a detailed monitoring of the quality of these products is thus mandatory. Besides, being the accuracy of the image geo-location strongly related with the pointing performance of the platform and with the on-board timing stability, monitoring from ground of the behaviour of the on-board sensors and clock is needed. This paper presents an overview of the Flight Dynamics operations performed during the different phases of the MetOp A mission up to routine. The activities performed to validate all the Flight Dynamics functions, characterize the behaviour of the satellite and monitor the performances of the Flight Dynamics facility will be highlighted. The MetOp Flight Dynamics Operations team is led by Anders Meier Soerensen and composed by Pier Luigi Righetti, Francisco Sancho, Antimo Damiano and David Lazaro. The team is supported by Hilda Meixner, responsible for all Flight Dynamics validation activities.

A Survey of Metal Lines at High Redshift. II. SDSS Absorption Line Studies—O VI Line Density, Space Density, and Gas Metallicity at z abs ~ 3.0

NASA Astrophysics Data System (ADS)

Frank, S.; Mathur, S.; Pieri, M.; York, D. G.

2010-09-01

We have analyzed a large data set of O VI absorber candidates found in the spectra of 3702 Sloan Digital Sky Survey (SDSS) quasars, focusing on a subsample of 387 active galactic nuclei sight lines with an average S/N >=5.0, allowing for the detection of absorbers above a rest-frame equivalent width limit of W r >= 0.19 Å for the O VI 1032 Å component. Accounting for random interlopers mimicking an O VI doublet, we derive for the first time a secure lower limit for the redshift number density ΔN/Δz for redshifts z abs >= 2.8. With extensive Monte Carlo simulations, we quantify the losses of absorbers due to blending with the ubiquitous Lyα forest lines and estimate the success rate of retrieving each individual candidate as a function of its redshift, the emission redshift of the quasar, the strength of the absorber, and the measured signal-to-noise ratio (S/N) of the spectrum by modeling typical Lyman forest spectra. These correction factors allow us to derive the "incompleteness and S/N-corrected" redshift number densities of O VI absorbers: ΔN O VI,c /Δzc (2.8 < z < 3.2) = 4.6 ± 0.3, ΔN O VI,c /Δzc (3.2 < z < 3.6) = 6.7 ± 0.8, and ΔN O VI,c /Δzc (3.6 < z < 4.0) = 8.4 ± 2.9. We can place a secure lower limit for the contribution of O VI to the closure mass density at the redshifts probed here: ΩO VI (2.8 < z < 3.2) >= 1.9 × 10-8 h -1. We show that the strong lines we probe account for over 65% of the mass in the O VI absorbers; the weak absorbers, while dominant in line number density, do not contribute significantly to the mass density. Making a conservative assumption about the ionization fraction, {O VI}/{O}, and adopting the Anders & Grevesse solar abundance values, we derive the mean metallicity of the gas probed in our search: ζ(2.8 < z < 3.2) >= 3.6 × 10-4 h, in good agreement with other studies. These results demonstrate that large spectroscopic data sets such as SDSS can play an important role in QSO absorption line studies, in spite of the relatively low resolution.

Density and Viscosity Measurement of Liquid FeS at High Pressure and High Temperature Using Synchrotron X-ray

NASA Astrophysics Data System (ADS)

Yu, T.; Long, H.; Young, C.; Wang, L.; Chen, J.

2005-12-01

From previous experimental and theoretical studies, sulfur has been considered one of the possible light elements in the core that might be responsible for the large density deficit when compared with the theoretical pure Fe core (Ganapathy and Anders, 1974; Ahrens and Jeanloz, 1987). Therefore, understanding the physical properties of liquid FeS will help us reveal the details of the Earth?|s core. This study focused on the liquid state of sulfur in iron due to sulfur?|s lack of amount in the mantle; easiness to alloy with iron; and the predicted 5 wt% ~10 wt% amount of this light element in the core (Ahrens, 1979; Sherman, 1997). Modern development of the multi-anvil high pressure apparatus limits the pressure range of the experiments (<30 GPa). It is somewhat low if comparing with the outer core pressure condition. Therefore, extrapolation of data derived at low pressure range to the condition of the outer core (>130 GPa) has to be applied, and may produce results that are far from the true numbers. However, at the point while the techniques are limited, studying the physical properties of the liquid-phase FeS at relatively low pressures still provides us a better picture of the physical behavior of the outer core comparing with data derived from solid state FeS experiments. Pervious studies on the viscosity of the Fe-FeS system (LeBlanc and Secco, 1996; Dobson et al., 2000; Urakawa et al., 2001; Secco et al., 2002) have presented different values of viscosity numbers with a maximum difference of two orders of magnitude. We have conducted the density measurements of liquid FeS (~36 wt% of S) up to 5.6 GPa in pressure and 1673K in temperature using the in-situ synchrotron-source x-ray absorption setup at Beamline X17B2, NSLS. The viscosity measurements were conducted by the x-ray radiograph technique combined with the falling sphere method. The falling sphere method applied at the experiment is suitable for liquids with viscosities between 10-3 Pa-s and 105 Pa-s (LeBlanc et al., 1999). We used tungsten spheres in our viscosity measurement experiments. We analyzed the sphere falling motion in the sample chamber at high pressure and high temperature. And by applying our density compression curve of liquid FeS to the Stokes?| viscometry method, we were able to derive the viscosity of liquid FeS.

The effects of climate changes on soil methane oxidation in a dry Arctic tundra

NASA Astrophysics Data System (ADS)

D'Imperio, Ludovica

2014-05-01

The effects of climate changes on soil methane oxidation in a dry Arctic tundra. Ludovica D'Imperio1, Anders Michelsen1, Christian J. Jørgensen1, Bo Elberling1 1Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Denmark At Northern latitudes climatic changes are predicted to be most pronounced resulting in increasing active layer depth and changes in growing season length, vegetation cover and nutrient cycling. As a consequence of increased temperature, large stocks of carbon stored in the permafrost-affected soils could become available for microbial transformations and under anoxic conditions result in increasing methane production affecting net methane (CH4) budget. Arctic tundra soils also serves as an important sink of atmospheric CH4 by microbial oxidation under aerobic conditions. While several process studies have documented the mechanisms behind both production and emissions of CH4 in arctic ecosystems, an important knowledge gap exists with respect to the in situ dynamics of microbial-driven uptake of CH4 in arctic dry lands which may be enhanced as a consequence of global warming and thereby counterbalancing CH4 emissions from Arctic wetlands. In-situ methane measurements were made in a dry Arctic tundra in Disko Island, Western Greenland, during the summer 2013 to assess the role of seasonal and inter-annual variations in temperatures and snow cover. The experimental set-up included snow fences installed in 2012, allowed investigations of the emissions of GHGs from soil under increased winter snow deposition and ambient field conditions. The soil fluxes of CH4 and CO2 were measured using closed chambers in manipulated plots with increased summer temperatures and shrub removal with or without increased winter precipitation. At the control plots, the averaged seasonal CH4 oxidation rates ranged between -0.05 mg CH4 m-2 hr-1 (end of August) and -0.32 mg CH4 m-2 hr-1 (end of June). In the plots with increased summer temperatures the rates ranged between -0.08 mg CH4 m-2 hr-1 (end of August) and -0.40 mg CH4 m-2 hr-1 (beginning of July). Preliminary results show a significant effect of increased winter precipitation (p<0.01) over the season as well as a significant warming effect (p<0.05) during July and August. These results suggest that in a warmer climate increasing CH4 uptake rates in dry Arctic soils could become an important factor for net CH4 budget.

Structural and Functional Connectivity from Unmanned-Aerial System Data

NASA Astrophysics Data System (ADS)

Masselink, Rens; Heckmann, Tobias; Casalí, Javier; Giménez, Rafael; Cerdá, Artemi; Keesstra, Saskia

2017-04-01

Over the past decade there has been an increase in both connectivity research and research involving Unmanned-Aerial systems (UASs). In some studies, UASs were successfully used for the assessment of connectivity, but not yet to their full potential. We present several ways to use data obtained from UASs to measure variables related to connectivity, and use these to assess both structural and functional connectivity. These assessments of connectivity can aid us in obtaining a better understanding of the dynamics of e.g. sediment and nutrient transport. We identify three sources of data obtained from a consumer camera mounted on a fixed-wing UAS, which can be used separately or combined: Visual and near-infrared imagery, point clouds, and digital elevation models (DEMs). Imagery (or: orthophotos) can be used for (automatic) mapping of connectivity features like rills, gullies and soil and water conservation measures using supervised or unsupervised classification methods with e.g. Object-Based Image Analysis. Furthermore, patterns of soil moisture in the top layers can be extracted from visual and near-infrared imagery. Point clouds can be analysed for vegetation height and density, and soil surface roughness. Lastly, DEMs can be used in combination with imagery for a number of tasks, including raster-based (e.g. DEM derivatives) and object-based (e.g., feature detection) analysis: Flow routing algorithms can be used to analyse potential pathways of surface runoff and sediment transport. This allows for the assessment of structural connectivity through indices that are based, for example, on morphometric and other properties of surfaces, contributing areas, and pathways. Third, erosion and deposition can be measured by calculating elevation changes from repeat surveys. From these "intermediate" variables like roughness, vegetation density and soil moisture, structural connectivity and functional connectivity can be assessed by combining them into a dynamic index of connectivity, use them in connectivity modelling (Masselink et al., 2016b) or be combined with measured data of water and sediment fluxes (Masselink et al., 2016a). References Masselink, R.J.H., Heckmann, T., Temme, A.J.A.M., Anders, N.S., Gooren, H.P.A., Keesstra, S.D., 2016a. A network theory approach for a better understanding of overland flow connectivity. Hydrol. Process. doi:10.1002/hyp.10993 Masselink, R.J.H., Keesstra, S.D., Temme, A.J.A.M., Seeger, M., Giménez, R., Casalí, J., 2016b. Modelling Discharge and Sediment Yield at Catchment Scale Using Connectivity Components. Land Degrad. Dev. 27, 933-945. doi:10.1002/ldr.2512

Transfer-Matrix Method for Solving the Spin 1/2 Antiferromagnetic Heisenberg Chain

NASA Astrophysics Data System (ADS)

Garcia-Bach, M. A.; Klein, D. J.; Valenti, R.

Following the discovery of high Tc superconductivity in the copper oxides, there has been a great deal of interest in the RVB wave function proposed by Anderson [1]. As a warm-up exercise we have considered a valence-bond wave function for the one dimensional spin-1/2 Heisenberg chain. The main virtue of our work is to propose a new variational singlet wavefunction which is almost analytically tractable by a transfer-matrix technique. We have obtained the ground state energy for finite as well as infinite chains, in good agreement with exact results. Correlation functions, excited states, and the effects of other interactions (e.g., spin-Peierls) are also accessible within this scheme [2]. Since the ground state of the chain is known to be a singlet (Lieb & Mattis [3]), we write the appropriate wave function as a superposition of valence-bond singlets, |ψ > =∑ limits k C k | k>, where |k> is a spin configuration obtained by pairing all spins into singlet pairs, in a way which is common in valence-bond calculations of large molecules. As in that case, each configuration, |k>, can be represented by a Rümer diagram, with directed bonds connecting each pair of spins on the chain. The ck's are variational co-efficients, the form of which is determined as follows: Each singlet configuration (Rümer diagram) is divided into "zones", a "zone" corresponding to the region between two consecutive sites. Each zone is indexed by its distance from the end of the chain and by the number of bonds crossing it. Our procedure assigns a variational parameter, xij, to the jth zone, when crossed by i bonds. The resulting wavefunction for an N-site chain is written as |ψ > =∑ limits k ∏ M limits { i =1} ∏ { N -1}limits { j =1} X ij{ m ij (k)} | k> where mij(k) equals 1 when zone j is crossed by i bonds and zero otherwise. To make the calculation tractable we reduce the number of variational parameters by disallowing configurations with bonds connecting any two sites separated by more than 2M lattice points. (For simplicity, we have limited ourselves to M=3, but the scheme can be used for any M). With the simple ansatz, matrix elements can be calculated by a transfer-matrix method. To understand the transfer-matrix method note that since only local zone parameters appear in the description of each state |k>, matrix elements and overlaps, < k| bar S q bar S{ q +1} |k'> and , are completely specified by a small number of "local states" associated with each zone. Within a given zone a local state is defined by (i) the number of bonds crossing the zone and (ii), by whether the bonds originate from the initial (|k>) or final (|k'>) state. It is then easy to see that "local states" of consecutive zones are connected by a 15 × 15 transfer matrix (for the case M=3). Furthermore, the overlap matrix element can be written as a product of transfer-matrices associated with each zone of the chain. When calculating matrix elements of the Hamiltonian, an additional matrix, U, must be defined, to represent the particular zone involving the two spins connected by the Heisenberg interaction. The relevant details as well as the comparison with exact results will be given elsewhere. We are planning to ultimately apply this method to the two dimensional case, and hope to include the effects of holes.

Feasibility of Gamified Mobile Service Aimed at Physical Activation in Young Men: Population-Based Randomized Controlled Study (MOPO).

PubMed

Leinonen, Anna-Maiju; Pyky, Riitta; Ahola, Riikka; Kangas, Maarit; Siirtola, Pekka; Luoto, Tim; Enwald, Heidi; Ikäheimo, Tiina M; Röning, Juha; Keinänen-Kiukaanniemi, Sirkka; Mäntysaari, Matti; Korpelainen, Raija; Jämsä, Timo

2017-10-10

The majority of young people do not meet the recommendations on physical activity for health. New innovative ways to motivate young people to adopt a physically active lifestyle are needed. The study aimed to study the feasibility of an automated, gamified, tailored Web-based mobile service aimed at physical and social activation among young men. A population-based sample of 496 young men (mean age 17.8 years [standard deviation 0.6]) participated in a 6-month randomized controlled trial (MOPO study). Participants were randomized to an intervention (n=250) and a control group (n=246). The intervention group was given a wrist-worn physical activity monitor (Polar Active) with physical activity feedback and access to a gamified Web-based mobile service, providing fitness guidelines, tailored health information, advice of youth services, social networking, and feedback on physical activity. Through the trial, the physical activity of the men in the control group was measured continuously with an otherwise similar monitor but providing only the time of day and no feedback. The primary outcome was the feasibility of the service based on log data and questionnaires. Among completers, we also analyzed the change in anthropometry and fitness between baseline and 6 months and the change over time in weekly time spent in moderate to vigorous physical activity. Mobile service users considered the various functionalities related to physical activity important. However, compliance of the service was limited, with 161 (64.4%, 161/250) participants visiting the service, 118 (47.2%, 118/250) logging in more than once, and 41 (16.4%, 41/250) more than 5 times. Baseline sedentary time was higher in those who uploaded physical activity data until the end of the trial (P=.02). A total of 187 (74.8%, 187/250) participants in the intervention and 167 (67.9%, 167/246) in the control group participated in the final measurements. There were no differences in the change in anthropometry and fitness from baseline between the groups, whereas waist circumference was reduced in the most inactive men within the intervention group (P=.01). Among completers with valid physical activity data (n=167), there was a borderline difference in the change in mean daily time spent in moderate to vigorous physical activity between the groups (11.9 min vs -9.1 min, P=.055, linear mixed model). Within the intervention group (n=87), baseline vigorous physical activity was inversely associated with change in moderate to vigorous physical activity during the trial (R=-.382, P=.01). The various functionalities related to physical activity of the gamified tailored mobile service were considered important. However, the compliance was limited. Within the current setup, the mobile service had no effect on anthropometry or fitness, except reduced waist circumference in the most inactive men. Among completers with valid physical activity data, the trial had a borderline positive effect on moderate to vigorous physical activity. Further development is needed to improve the feasibility and adherence of an integrated multifunctional service. Clinicaltrials.gov NCT01376986; http://clinicaltrials.gov/ct2/show/NCT01376986 (Archived by WebCite at http://www.webcitation.org/6tjdmIroA). ©Anna-Maiju Leinonen, Riitta Pyky, Riikka Ahola, Maarit Kangas, Pekka Siirtola, Tim Luoto, Heidi Enwald, Tiina M Ikäheimo, Juha Röning, Sirkka Keinänen-Kiukaanniemi, Matti Mäntysaari, Raija Korpelainen, Timo Jämsä. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 10.10.2017.

A New Estimate for Total Offset on the Southern San Andreas Fault: Implications for Cumulative Plate Boundary Shear in the Northern Gulf of California

NASA Astrophysics Data System (ADS)

Darin, M. H.; Dorsey, R. J.

2012-12-01

Development of a consistent and balanced tectonic reconstruction for the late Cenozoic San Andreas fault (SAF) in southern California has been hindered for decades by incompatible estimates of total dextral offset based on different geologic cross-fault markers. The older estimate of 240-270 km is based on offset fluvial conglomerates of the middle Miocene Mint Canyon and Caliente Formations west of the SAF from their presumed source area in the northern Chocolate Mountains NE of the SAF (Ehlig et al., 1975; Ehlert, 2003). The second widely cited offset marker is a distinctive Triassic megaporphyritic monzogranite that has been offset 160 ± 10 km between Liebre Mountain west of the SAF and the San Bernadino Mountains (Matti and Morton, 1993). In this analysis we use existing paleocurrent data and late Miocene clockwise rotation in the eastern Transverse Ranges (ETR) to re-assess the orientation of the piercing line used in the 240 km-correlation, and present a palinspastic reconstruction that satisfies all existing geologic constraints. Our reconstruction of the Mint Canyon piercing line reduces the original estimate of 240-270 km to 195 ± 15 km of cumulative right-lateral slip on the southern SAF (sensu stricto), which is consistent with other published estimates of 185 ± 20 km based on correlative basement terranes in the Salton Trough region. Our estimate of ~195 km is consistent with the lower estimate of ~160 km on the Mojave segment because transform-parallel extension along the southwestern boundary of the ETR during transrotation produces ~25-40 km of displacement that does not affect offset markers of the Liebre/San Bernadino correlation located northwest of the ETR rotating domain. Reconciliation of these disparate estimates places an important new constraint on the total plate boundary shear that is likely accommodated in the adjacent northern Gulf of California. Global plate circuit models require ~650 km of cumulative Pacific-North America (PAC-NAM) relative plate motion since ~12 Ma (Atwater and Stock, 1998). We propose that the continental component of PAC-NAM shear is accommodated by: (1) 195 ± 15 km on the southern SAF (this study); (2) 12 ± 2 km on the Whittier-Elsinore fault; (3) 75 ± 20 km of cumulative shear across the central Mojave in the eastern California shear zone; (4) 30 ± 4 km of post-13 Ma slip on the Stateline fault; and (5) 47 ± 18 km of NW-directed translation produced by north-south shortening. Together, these components sum to 359 ± 31 km of net dextral displacement on the SAF system (sensu lato) in southern California since ca. 12 Ma, or ~300 km less than what is required by the global plate circuit. This suggests that the continental component of post-12 Ma PAC-NAM transform motion can be no more than ~390 km in the adjacent northern Gulf of California, substantially less than the 450 km of shear proposed in some models. We suggest that the remaining ~270-300 km of NW-directed relative plate motion is accommodated by a small component of late Miocene extension and roughly 225 km of slip on the offshore borderland fault system west of Baja California.

Does the West Salton Detachment extend through San Gorgonio Pass, southern California?

NASA Astrophysics Data System (ADS)

Matti, J. C.; Langenheim, V. E.

2008-12-01

Rift-related extension and low-angle crustal detachment are key structural elements of the late Cenozoic southern San Andreas Fault system, as manifested by the West Salton Detachment (WSD). The most northwestern exposure of the WSD is in the Santa Rosa Mts (SRM), where the Zosel Fault bottoms a hangingwall sequence of upper Cenozoic marine and terrestrial sedimentary deposits that include stratigraphic units well known throughout the Salton Trough region. We have used geologic and geophysical data to investigate the distribution of the WSD system in the northern Salton Trough, including its possible extension into and beyond San Gorgonio Pass. Although the WSD is not exposed north of the SRM, late Miocene marine and terrigenous sedimentary rocks at Garnet Hill probably are hangingwall deposits squeezed up within the San Andreas Fault zone. West of Garnet Hill lie San Gorgonio Pass (SGP) and the 3 km-high northern escarpment of the San Jacinto Mountains (SJM). In SGP, upper Cenozoic sedimentary rocks south of the Banning strand of the San Gabriel Fault include the marine Imperial Formation and associated terrestrial deposits, a sequence similar to that in the WSD hangingwall throughout the greater Salton Trough region. We propose that the WSD originally extended from the NW head of Coachella Valley west into SGP, where the detachment may form the base of the Cenozoic marine and terrestrial sedimentary sequence. The WSD probably continues west beyond SGP, with extensional translation decreasing until the detachment intersects the Banning Fault near Calimesa. There, we propose that the WSD underlies a subsurface sedimentary package north of the San Timoteo badlands and south of the Banning Fault that a gravity low suggests is 2 km thick, and that reportedly contains marine sediment penetrated in boreholes. When ~44 km of right-slip is restored on the Banning Fault (Matti and Morton, 1993), the Calimesa low restores opposite a similar low in the northwestern Coachella Valley. The juxtaposed gravity lows mark a late Cenozoic depocenter that formed at the NW head of the Salton Trough during evolution of the San Gabriel and San Andreas Faults (10 Ma to 1.2 Ma). This reconstruction has several implications: (1) the WSD was active while the late Cenozoic sedimentary sequence in SGP accumulated in its hangingwall at 7 Ma (marine Imperial Fm) and probably as early as 10 Ma (Hathaway Fm); (2) At that time the San Jacinto Mts (SJM) began to rise in the WSD footwall, shedding sediment and landslide breccia into the SGP basin. Simultaneously, Transverse Ranges sources shed sediment southwest, south, and southeast into the SGP basin and the adjoining San Timoteo basin; (3) Prior to disruption by right-slip on the Banning Fault, the WSD probably extended around the NW head of the Salton Trough, where the detachment would have separated footwall crystalline rocks of SGP from hangingwall deposits of the Salton Trough (Coachella Fanglomerate, Imperial and Painted Hill fms). The enigmatic Whitewater Fault in the SE San Bernardino Mts may be part of the WSD. (4) Because extensional translation on the WSD diminished westward through SGP, it is doubtful that >3 km of topographic relief on the WSD footwall in the SJM resulted from footwall uplift alone during the period 10 Ma to 1.2 Ma. Post-WSD Quaternary uplift must account for an unknown component of this relief.

Fragmented Landscapes in the San Gorgonio Pass Region: Insights into Quaternary Strain History of the Southern San Andreas Fault System

NASA Astrophysics Data System (ADS)

Kendrick, K. J.; Matti, J. C.; Landis, G. P.; Alvarez, R. M.

2006-12-01

The San Gorgonio Pass (SGP) region is a zone of structural complexity within the southern San Andreas Fault system that is characterized by (1) multiple strands of the San Andreas Fault (SAF), (2) intense and diverse microseismicity, (3) contraction within the SGP fault zone (SGPfz), and (4) complex and diverse landforms - all a consequence of structural complications in the vicinity of the southeastern San Bernardino Mountains (SBM). Multiple strands of the SAF zone in the SGP region partition the landscape into discrete geomorphic/geologic domains, including: San Gorgonio Mountain (SGM), Yucaipa Ridge (YR), Kitching Peak (KP), Pisgah Peak (PP), and Coachella Valley (CV) domains. The morphology of each domain reflects the tectonic history unique to that region. Development of the SGP knot in the Mission Creek strand of the SAF (SAFmi) led to westward deflection of the SAFmi, juxtaposition of the KP, PP, and SGM domains, initiation of uplift of YR domain along thrust faults in headwaters of San Gorgonio River, and development of the San Jacinto Fault. Slip on the SAF diminished as a result, thereby allowing integrated drainage systems to develop in the greater SGP region. San Gorgonio River, Whitewater River, and Mission Creek are discrete drainages that transport sediment across the SGM, YR, PP, KP, and CV domains into alluvial systems peripheral to the SGP region. There, depositional units (San Timoteo Formation, upper member, deformed gravels of Whitewater River) all contain clasts of SBM-type and San Gabriel Mountain-type basement, thus constraining slip on the SAF in the SGP region. Middle and late Pleistocene slip on the Mill Creek strand of the SAF (SAFm) in the SGP region has attempted to bypass the SGP knot, and has disrupted landscapes established during SAFmi quiescence. Restoration of right-slip on the SAFm is key to deciphering landscape history. Matti and others (1985, 1992) proposed that a bi-lobed alluvial deposit in the Raywood Flats area has been displaced by 8-10 km from entrenched bedrock drainages north of the SAFm (North Fork Whitewater River and Hell-For-Sure Canyon). This restoration, along with restoration of 3-4 km of dextral-slip along SAFmi, leads to an integrated drainage network that extended from San Gorgonio Peak southward across the SAFm and SAFmi, through the San Timoteo drainage basin and ultimately to the Santa Ana River drainage. Following final slip on the SAFmi, which occurred between approximately 1.2 and 0.5 Ma, the 8-10 km dextral-slip reconstruction on the SAFm can be used to restore the ancestral Mission Creek drainage system, which has always flowed southeast. A large alluvial-fan complex that overlies the SAFmi strand developed where the ancestral Mission Creek River debouched into the Coachella Valley. Analysis of cosmogenic radionuclides (21Ne from quartz) from surface boulders indicates that oldest deposits in the fan complex are about 400ka old, compatible with pedogenic development on the oldest surface. Approximately 2-4 km dextral slip on the youngest strands of the SAF (Banning and Garnet Hill) represents the latest bypass of the SGP structural knot. Cumulative displacement on all strands of the SAF in the greater SGP region appears to have been no more than ~18 km since inception of the left step in the SAFmi. Regional evidence suggests that this event initiated at ~1.2Ma, leading to a Quaternary slip rate on the SAF at SGP of no more than 10-15 mm/yr.

EDITORIAL: Dialog on Science and Policy to Address the Climate Crisis to conclude the International Association of Research Universities Climate Congress, Copenhagen, Denmark Dialog on Science and Policy to Address the Climate Crisis to conclude the International Association of Research Universities Climate Congress, Copenhagen, Denmark

NASA Astrophysics Data System (ADS)

Baer, Paul; Kammen, Daniel M.

2009-06-01

This is not the usual Editor-in-Chief letter, namely one that focuses on the accomplishments of the journal—and for ERL they have been numerous this year—but a recognition of the critical time that we are now in when it comes to addressing not only global climate change, but also the dialog between science and politics. In recognition of the many 'tipping points' that we now confront—ideally some of them positive social moments—as well as the clear scientific conclusion that environmental tipping points are points of long-lasting disruption, this paper takes a different form than I might have otherwise written. While the scientific body of knowledge around global environmental change mounts, so too, do the hopeful signs that change can happen. The election of Barack Obama is unquestionably one such sign, witnessed by the exceptional interest that his story has brought not only to US politics, but also to global views of the potential of the United States, as well as to the potential role of science and investigation in addressing pressing issues. In light of these inter-related issues, reproduced here—largely due to the efforts of Paul Baer to transcribe a remarkable conversation—is a dialog not only on the science of global warming and the potential set of means to address this issue, but also on the interaction between research, science and the political process. The dialog itself is sufficiently important that I will dispense with the usual discussion of the exciting recognition that ERL has received with an ISI rating (a factor rapidly increasing), the high levels of downloads of our papers (for some articles over 5000 and counting), and the many news and scientific publications picking up ERL articles (in recent days alone Science, Environmental Science and Technology, and The Economist). This conversation was the concluding plenary session of the 10-12 March International Association of Research Universities (IARU) Conference on Climate Change (http://climatecongress.ku.dk/). Conference Chair Professor Katherine Richardson began the panel by reading the 'key messages'. She then she asked the panelists—Professor Stefan Rahmstorf, Professor Will Steffen, Lord Nicholas Stern, and Professor Dan Kammen to respond. After that, she invited the Danish Prime Minister, Mr Anders Fogh Rasmussen, to respond to the messages. Next there was a dialogue between the panelists and the Prime Minister, with closing remarks from the Prime Minister.

EDITORIAL: XXVI IUPAP Conference on Computational Physics (CCP2014)

NASA Astrophysics Data System (ADS)

Sandvik, A. W.; Campbell, D. K.; Coker, D. F.; Tang, Y.

2015-09-01

The 26th IUPAP Conference on Computational Physics, CCP2014, was held in Boston, Massachusetts, during August 11-14, 2014. Almost 400 participants from 38 countries convened at the George Sherman Union at Boston University for four days of plenary and parallel sessions spanning a broad range of topics in computational physics and related areas. The first meeting in the series that developed into the annual Conference on Computational Physics (CCP) was held in 1989, also on the campus of Boston University and chaired by our colleague Claudio Rebbi. The express purpose of that meeting was to discuss the progress, opportunities and challenges of common interest to physicists engaged in computational research. The conference having returned to the site of its inception, it is interesting to recect on the development of the field during the intervening years. Though 25 years is a short time for mankind, computational physics has taken giant leaps during these years, not only because of the enormous increases in computer power but especially because of the development of new methods and algorithms, and the growing awareness of the opportunities the new technologies and methods can offer. Computational physics now represents a ''third leg'' of research alongside analytical theory and experiments in almost all subfields of physics, and because of this there is also increasing specialization within the community of computational physicists. It is therefore a challenge to organize a meeting such as CCP, which must have suffcient depth in different areas to hold the interest of experts while at the same time being broad and accessible. Still, at a time when computational research continues to gain in importance, the CCP series is critical in the way it fosters cross-fertilization among fields, with many participants specifically attending in order to get exposure to new methods in fields outside their own. As organizers and editors of these Proceedings, we are very pleased with the high quality of the papers provided by the participants. These articles represent a good cross-section of what was presented at the meeting, and it is our hope that they will not only be useful individually for their specific scientific content but will also represent a historical snapshot of the state of computational physics that they represent collectively. The remainder of this Preface contains lists detailing the organizational structure of CCP2014, endorsers and sponsors of the meeting, plenary and invited talks, and a presentation of the 2014 IUPAP C20 Young Scientist Prize. We would like to take the opportunity to again thank all those who contributed to the success of CCP214, as organizers, sponsors, presenters, exhibitors, and participants. Anders Sandvik, David Campbell, David Coker, Ying Tang

Lonsdaleite has been used as an indicator of shock from cratering events, but does it exist?

NASA Astrophysics Data System (ADS)

Nemeth, P.; Garvie, L. A.; Buseck, P. R.

2013-12-01

In 1967 a new diamond polymorph was described from the Canyon Diablo iron meteorite [1] and called lonsdaleite (also referred to as hexagonal diamond. It was identified from reflections (e.g., at 0.218, 0.193, and 0.150 nm), additional to those in diamond, that were indexed in terms of a hexagonal cell [1]. Lonsdaleite was attributed to shock-induced transformation of graphite within the iron meteorite upon impact [1, 2] and has subsequently been used as an indicator of shock and meteorite impact [3, 4, 5]. Given the importance of lonsdaleite, we reinvestigated the structure of the shock-formed diamond and lonsdaleite from the Canyon Diablo meteorite with an aberration-corrected ultra-high-resolution scanning transmission electron microscope (STEM), with the view of providing further insights into the shock-forming mechanism. The STEM images allowed direct structural interpretation at 0.1-nm resolution and showed that the samples consist of single-crystal and twinned diamond, as well as graphite intimately associated at the nanoscale. A characteristic feature of the STEM images is stacking faults and twins (111, 200, 113) that interrupt the regularity of the crystal structure. Uncommon, subnanometer-sized regions occur with two- and four-layer hexagonal symmetry, though these regions merge into diamond with stacking faults. Although we did not find lonsdaleite, the defects can give rise to extra reflections like those attributed to lonsdaleite. For example, the (113) diamond twin results in a 0.216-nm spacing that matches that of the broad 0.218-nm lonsdaleite peak. Our observations from Canyon Diablo provide a new understanding of shocked diamond structures and question the existence of lonsdaleite and its inferred geologic implication, although the abundance of diamond twinning and stacking faults may be indicative of shock metamorphism. [1] Frondel, C. & Marvin, U.B. (1967) Lonsdaleite, a hexagonal polymorph of diamond. Nature 217, 587-589. [2] Lipschutz, M. & Anders, E. (1961) The record in the meteorites-IV: Origin of diamonds in iron meteorites. Geochimica et Cosmochimica Acta 24, 83-105. [3] Kennet, D. J., Kennet, J. P., West, A., Mercer, C., Que Hee, S. S., Bement, L., Bunch, T. E., Sellers, M., & Wolbach, W. S. (2009) Nanodiamonds in the Younger Dryas boundary sediment layers. Science 323, 94. [4] Le Guillou, C., Rouzaud, J.N., Remusat, L., Jambon, A., & Bourot-Denise, M. (2010) Structures, origin and evolution of various carbon phases in the ureilite Northwest Africa 4742 compared with laboratory-shocked graphite. Geochimica Et Cosmochimica Acta 74(14), 4167-4185. [5] Hough, R.M., Gilmour, I., Pillinger, C.T., Arden, J.W., Gilkes, K.W.R., Yuan, J. & Milledge, H.J. (1995) Diamond and silicon carbide in an impact melt rock from the Ries impact crater. Nature 378, 41-44.

[Not Available].

PubMed

Hainschitz, I; Rieger, K; Siegl, H

2002-06-01

In Austria an index of 3 μg/kg of Ochratoxin A for coffee, 0,3 μg/kg for fruit juices and 0,2 μg/kg for beer is discussed. The laboratory of the food inspection authority of the state of Vorarlberg investigated the contribution of selected foodstuffs to the daily OTA intake and compared it with the recommendation of the scientific food committee of the EC. The focal point of this study was on beverages (coffee, coffee substitutes, beer and fruit juices) and their ingredients.ZUSAMMENFASSUNG: Die Untersuchungsergebnisse von Bier, Fruchtsaft und Kaffee [Diagramm 1] zeigen, dass die Mehrzahl der Proben nur sehr schwach bis gar nicht belastet waren. Die OTA-Belastung lag bei der Mehrzahl der Proben unter der Nachweisgrenze von 0,3 μg/kg bzw. 0,01μg/1. Einzelne Proben waren aber erheblich belastet, sodass bei starkem Konsum (Fruchtsaft im Sommer) eine überschreitung der vom SCF vorgeschlagenen Höchstmenge nicht auszuschließen ist. Die Ergebnisse der Kaffeemitteluntersuchung [Diagramm 2] belegen eine höhere OTA-Belastung bei mehr als der Hälfte der Proben. Wenn die vom SCF vorgeschlagene Höchstaufnahme von 5 ng pro Tag und kg Körpergewicht zu Grunde gelegt wird, resultiert für eine 60 kg schwere Person ein Wert von 0,3 μg/Tag. Das bedeutet bei einem mit 100 μg/kg OTA kontaminierten Kaffeeersatz und dem Konsum nur einer Tasse (5 - 7 g Pulver), dass alleine aus dieser Quelle diese Höchstaufnahme deutlich überschritten wird. Der Eintrag über die restliche Nahrung wie Cerealien, die für etwa die Hälfte der OTA-Aufnahme verantwortlich sind, bleibt hier unberücksichtigt. Die Untersuchungen belegen, dass die Einhaltung der in österreich vorgeschlagenen Richtwerte bei Bier, Fruchtsäften und Kaffee keine Schwierigkeiten bereitet. Für Kaffeemittel und andere Trockenfrüchte als Weintrauben [3] wurde allerdings noch kein Richtwert vorgeschlagen. Die Ergebnisse belegen aber, dass gerade für Kaffemittel und verschiedene Trockenfrüchte vor dem Hintergrund fehlender Höchstwerte ein Richtwert in der Größenordnung von 3 μg/kg bzw. 10 μg/kg hilfreich wäre, bis die Festlegung der gemeinschaftsrechtlicher Höchstgehalte erfolgt. Mit Hinblick auf die in der Einleitung beschriebene toxische Wirkung von OTA ist es im Sinne eines vorbeugenden Verbraucherschutzes wichtig, diese hochbelasteten Chargen zu erkennen und aus dem Verkehr zu nehmen. Ursache für die OTA-Kontamination ist vor allem eine mangelhafte Produktionshygiene in den Erzeugerländern. Dort liegt auch das größte Potential für eine Verringerung der OTA-Belastung. Die überprüfung der Lebensmittel auf Ochratoxin A durch die amtliche Lebensmittelkontrolle ist ein notwendiger Beitrag zum Schutz der öffentlichen Gesundheit und zur weiteren Reduktion der Aufnahme.

Does canopy mean N concentration explain differences in light use efficiency in 14 eddy-covariance sites?

NASA Astrophysics Data System (ADS)

Peltoniemi, Mikko; Pulkkinen, Minna; Kolari, Pasi; Mäkelä, Annikki

2010-05-01

Production efficiency models aim at explaining variation of vegetation productivity with climatic input and information on vegetation cover often obtained from satellite observations. It has been acknowledged that different plant species differ in their potential to assimilate carbon dioxide per unit of PAR (i.e light use efficiency, LUE). Subsequently, some LUE-based models apply different LUE-coefficients for different plant functional types. Leaf N concentrations differ between plant species, and related differences in light saturated photosynthesis rate (A_max) have been detected. How much these differences affect the ecosystem production or LUE is more obscure. Canopies acclimate to prevailing environmental conditions, which causes variation e.g. in the proportion of leaves exposed to direct sunlight, leaf morphology, structure,orientation, and vertical N distibution. Furthermore, a fair proportion of photosynthesis occurs during cloudy days, in which case high A_max is unessential, and number of these days differs by location. We studied if canopy mean N concentration could explain differences in LUE derived for 14 forest sites using eddy-covariance measurements. The largest actual LUE was estimated for each site directly as an upper percentile of the ratio of Gross Primary Production (GPP) to absorbed PAR. Potential LUE for each site, on the other hand, was estimated by parameterising a LUE-based production efficiency model (Prelued), which accounts for daily changes in weather (temperature, VPD, PAR). In this model structure, the LUE-parameter for each site, can be interpreted as the potential LUE under optimal environmental conditions, i.e when the environment is not limiting production at all. Averages of the largest actual LUE and potential LUE were higher in deciduous sites than in conifer sites. Canopy mean N correlated weakly with both the largest actual and potential LUE, and the correlation was also significant in conifer subset in the former case. Mean growing season VPD was the only climatic variable which correlated significantly with the largest actual LUE; none of them correlated with potential LUE. Inclusion of nitrogen in the Prelued-model structure did not improve the goodness of fit of the model. According to our results LUE correlates with mean canopy N concentration. The correlation of mean VPD with the largest actual LUE can also be explained with the model accounting for daily variation in climate, as was made with Prelued-model for the potential LUE. Further studies utilising seasonal values of canopy N are called upon. *Acknowledgements: Eero Nikinmaa, Pertti Hari, Timo Vesala, Tuomas Laurila, Fredrik Lagergren, Meelis Mölder, Anders Lindroth, Thomas Grünwald, Christian Bernhofer, Denis Loustau, Paul Berbigier, Beverly Law, Alison Dunn, Steve Wofsy, Torbjörn Johansson, Torben Christensen, Terry Callaghan, Hans Verbeeck, Remko Duursma, Leonardo Montagnani, Dario Papale, Andreas Ibrom, Ebba Dellwik, Kim Pilegaard, Kentaro Takagi, Eva van Gorsel, Heather Keith, Sonia Wharton, Matthias Falk, Kya Tha Paw U, Matt Schroeder, Jon Lloyd

Cataclastic flow kinematics inferred from magnetic fabrics at the Heart Mountain Detachment, Wyoming

NASA Astrophysics Data System (ADS)

Heij, Gerhard W.

The Heart Mountain Detachment (HMD) in Wyoming constitutes one of the largest known rock slides (3400 km2) on Earth. This detachment took place along the stratigraphic boundary between the Bighorn Dolomite at the hanging-wall and the Snowy Range Formation at the footwall. The slide resulted in the formation of an up to 3 m-thick carbonate ultracataclasite (CUC) at the base of the slide. The origin of the CUC and the nature of the triggering mechanism responsible for the initiation of the catastrophic movement have long been controversial. The most widely accepted theory is a mid-Eocene eruption in the Absaroka volcanic province that triggered rupture and subsequent detachment of Paleozoic rocks. Rapid sliding was facilitated by basal fluidization generated by thermo-mechanical decomposition of carbonate rocks. Here I present a proof of concept study addressing the question of the consistent magnetic fabrics observed in the CUC, as well as new observations indicating the discovery of mineral grains of volcanic origin within the CUC. Additionally, some constraints are placed on the thermo-chemical conditions operating at the base of this catastrophic landslide. Overall, the CUC displays an average magnetic susceptibility one order of magnitude higher (1803 . -6 [SI]) than the overlying Bighorn Dolomite (148 . -6 [SI]) and underlying Snowy Range Fm (636 . -6 [SI]). Anisotropy of magnetic susceptibility (AMS) data, field observations and microstructural analysis suggest that ferromagnetic (s.l) minerals in the CUC originate from the Bighorn Dolomite, the Tertiary volcanics and synkinematic thermal decomposition of pyrite into pyrrhotite and magnetite. Thermomagnetic investigations revealed a Curie temperature of 525°C which suggests that magnetite is the dominant magnetic carrier mineral in the CUC. Energy Dispersive Spectroscopy analyses confirm that this magnetite has a relatively low ulvospinel content. Magnetic hysteresis properties point to an average pseudo-single domain magnetic grain size or, alternatively, a mixture of single domain and multi-domain grains. The origin of AMS is magnetostatic, elucidated by a high degree of consistency between AMS directions and 3--D SPO directions. The anisotropy of magnetic susceptibility (AMS) directional data displays two dominant fabric orientations suggesting possible strain partitioning in the CUC. The consistency of magnetic fabrics suggests that the CUC followed a dominantly transpressive regime. The deformation mechanism causing the consistent AMS is a homogeneous passive rotation of magnetite grains. Microstructural analysis of iron bearing minerals suggests that a high oxygen fugacity was present in the CUC at the onset of the slide. Evidence for elevated temperatures in the CUC is shown by broken twins in calcite which form as result of dynamic recrystallization. High pore fluid in the CUC is indicated by CUC dikes intruding the hanging wall and by accretionary grains (lapilli). Finally, the presence of unserpentinized and a few weakly serpentinized olivine clasts in the CUC brings the "hot water" weakening mechanism proposed by Ahranov and Anders (2006) into question.

Designing, Prototyping and Evaluating Digital Mindfulness Applications: A Case Study of Mindful Breathing for Stress Reduction.

PubMed

Zhu, Bin; Hedman, Anders; Feng, Shuo; Li, Haibo; Osika, Walter

2017-06-14

During the past decade, there has been a rapid increase of interactive apps designed for health and well-being. Yet, little research has been published on developing frameworks for design and evaluation of digital mindfulness facilitating technologies. Moreover, many existing digital mindfulness applications are purely software based. There is room for further exploration and assessment of designs that make more use of physical qualities of artifacts. The study aimed to develop and test a new physical digital mindfulness prototype designed for stress reduction. In this case study, we designed, developed, and evaluated HU, a physical digital mindfulness prototype designed for stress reduction. In the first phase, we used vapor and light to support mindful breathing and invited 25 participants through snowball sampling to test HU. In the second phase, we added sonification. We deployed a package of probes such as photos, diaries, and cards to collect data from users who explored HU in their homes. Thereafter, we evaluated our installation using both self-assessed stress levels and heart rate (HR) and heart rate variability (HRV) measures in a pilot study, in order to measure stress resilience effects. After the experiment, we performed a semistructured interview to reflect on HU and investigate the design of digital mindfulness apps for stress reduction. The results of the first phase showed that 22 of 25 participants (88%) claimed vapor and light could be effective ways of promoting mindful breathing. Vapor could potentially support mindful breathing better than light (especially for mindfulness beginners). In addition, a majority of the participants mentioned sound as an alternative medium. In the second phase, we found that participants thought that HU could work well for stress reduction. We compared the effect of silent HU (using light and vapor without sound) and sonified HU on 5 participants. Subjective stress levels were statistically improved with both silent and sonified HU. The mean value of HR using silent HU was significantly lower than resting baseline and sonified HU. The mean value of root mean square of differences (RMSSD) using silent HU was significantly higher than resting baseline. We found that the differences between our objective and subjective assessments were intriguing and prompted us to investigate them further. Our evaluation of HU indicated that HU could facilitate relaxed breathing and stress reduction. There was a difference in outcome between the physiological measures of stress and the subjective reports of stress, as well as a large intervariability among study participants. Our conclusion is that the use of stress reduction tools should be customized and that the design work of mindfulness technology for stress reduction is a complex process, which requires cooperation of designers, HCI (Human-Computer Interaction) experts and clinicians. ©Bin Zhu, Anders Hedman, Shuo Feng, Haibo Li, Walter Osika. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 14.06.2017.

Methodology for the Incorporation of Passive Component Aging Modeling into the RAVEN/ RELAP-7 Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mandelli, Diego; Rabiti, Cristian; Cogliati, Joshua

2014-11-01

Passive system, structure and components (SSCs) will degrade over their operation life and this degradation may cause to reduction in the safety margins of a nuclear power plant. In traditional probabilistic risk assessment (PRA) using the event-tree/fault-tree methodology, passive SSC failure rates are generally based on generic plant failure data and the true state of a specific plant is not reflected realistically. To address aging effects of passive SSCs in the traditional PRA methodology [1] does consider physics based models that account for the operating conditions in the plant, however, [1] does not include effects of surveillance/inspection. This paper representsmore » an overall methodology for the incorporation of aging modeling of passive components into the RAVEN/RELAP-7 environment which provides a framework for performing dynamic PRA. Dynamic PRA allows consideration of both epistemic and aleatory uncertainties (including those associated with maintenance activities) in a consistent phenomenological and probabilistic framework and is often needed when there is complex process/hardware/software/firmware/ human interaction [2]. Dynamic PRA has gained attention recently due to difficulties in the traditional PRA modeling of aging effects of passive components using physics based models and also in the modeling of digital instrumentation and control systems. RAVEN (Reactor Analysis and Virtual control Environment) [3] is a software package under development at the Idaho National Laboratory (INL) as an online control logic driver and post-processing tool. It is coupled to the plant transient code RELAP-7 (Reactor Excursion and Leak Analysis Program) also currently under development at INL [3], as well as RELAP 5 [4]. The overall methodology aims to: • Address multiple aging mechanisms involving large number of components in a computational feasible manner where sequencing of events is conditioned on the physical conditions predicted in a simulation environment such as RELAP-7. • Identify the risk-significant passive components, their failure modes and anticipated rates of degradation • Incorporate surveillance and maintenance activities and their effects into the plant state and into component aging progress. • Asses aging affects in a dynamic simulation environment 1. C. L. SMITH, V. N. SHAH, T. KAO, G. APOSTOLAKIS, “Incorporating Ageing Effects into Probabilistic Risk Assessment –A Feasibility Study Utilizing Reliability Physics Models,” NUREG/CR-5632, USNRC, (2001). 2. T. ALDEMIR, “A Survey of Dynamic Methodologies for Probabilistic Safety Assessment of Nuclear Power Plants, Annals of Nuclear Energy, 52, 113-124, (2013). 3. C. RABITI, A. ALFONSI, J. COGLIATI, D. MANDELLI and R. KINOSHITA “Reactor Analysis and Virtual Control Environment (RAVEN) FY12 Report,” INL/EXT-12-27351, (2012). 4. D. ANDERS et.al, "RELAP-7 Level 2 Milestone Report: Demonstration of a Steady State Single Phase PWR Simulation with RELAP-7," INL/EXT-12-25924, (2012).« less

The Genesis Mission: Solar Wind Conditions, and Implications for the FIP Fractionation of the Solar Wind.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reisenfeld, D. B.; Wiens, R. C.; Barraclough, B. L.

2005-01-01

The NASA Genesis mission collected solar wind on ultrapure materials between November 30, 2001 and April 1, 2004. The samples were returned to Earth September 8, 2004. Despite the hard landing that resulted from a failure of the avionics to deploy the parachute, many samples were returned in a condition that will permit analyses. Sample analyses of these samples should give a far better understanding of the solar elemental and isotopic composition (Burnett et al. 2003). Further, the photospheric composition is thought to be representative of the solar nebula, so that the Genesis mission will provide a new baseline formore » the average solar nebula composition with which to compare present-day compositions of planets, meteorites, and asteroids. Sample analysis is currently underway. The Genesis samples must be placed in the context of the solar and solar wind conditions under which they were collected. Solar wind is fractionated from the photosphere by the forces that accelerate the ions off of the Sun. This fractionation appears to be ordered by the first ionization potential (FIP) of the elements, with the tendency for low-FIP elements to be over-abundant in the solar wind relative to the photosphere, and high-FIP elements to be under-abundant (e.g. Geiss, 1982; von Steiger et al., 2000). In addition, the extent of elemental fractionation differs across different solarwind regimes. Therefore, Genesis collected solar wind samples sorted into three regimes: 'fast wind' or 'coronal hole' (CH), 'slow wind' or 'interstream' (IS), and 'coronal mass ejection' (CME). To carry this out, plasma ion and electron spectrometers (Barraclough et al., 2003) continuously monitored the solar wind proton density, velocity, temperature, the alpha/proton ratio, and angular distribution of suprathermal electrons, and those parameters were in turn used in a rule-based algorithm that assigned the most probable solar wind regime (Neugebauer et al., 2003). At any given time, only one of three regime-specific collectors (CH, IS, or CME) was exposed to the solar wind. Here we report on the regime-specific solar wind conditions from in-situ instruments over the course of the collection period. Further, we use composition data from the SWICS (Solar Wind Ion Composition Spectrometer) instrument on ACE (McComas et al., 1998) to examine the FIP fractionation between solar wind regimes, and make a preliminary comparison of these to the FIP analysis of Ulysses/SWICS composition data (von Steiger et al. 2000). Our elemental fractionation study includes a reevaluation of the Ulysses FIP analysis in light of newly reported photospheric abundance data (Asplund, Grevesse & Sauval, 2005). The new abundance data indicate a metallicity (Z/X) for the Sun almost a factor of two lower than that reported in the widely used compilation of Anders & Grevesse (1989). The new photospheric abundances suggest a lower degree of solar wind fractionation than previously reported by von Steiger et al. (2000) for the first Ulysses polar orbit (1991-1998).« less

Improvements in the use of aquatic herbicides and establishment of future research directions

USGS Publications Warehouse

Getsinger, K.D.; Netherland, M.D.; Grue, C.E.; Koschnick, T.J.

2008-01-01

Peer-reviewed literature over the past 20 years identifies significant changes and improvements in chemical control strategies used to manage nuisance submersed vegetation. The invasive exotic plants hydrilla (Hydrilla verticillata L.f. Royle) and Eurasian watermilfoil (Myriophyllum spicatum L.) continue to spread and remain the plant species of greatest concern for aquatic resource managers at the national scale. Emerging exotic weeds of regional concern such as egeria (Egeria densa Planch.), curlyleaf pondweed (Potamogeton crispus L.), and hygrophila (Hygrophila polysperma (Roxb.) T. Anders), as well as native plants such as variable watermilfoil (Myriophyllum heterophyllum Michx), and cabomba (Cabomba caroliniana Gray) are invasive outside their home ranges. In addition, there is always the threat of new plant introductions such as African elodea (Lagarosiphon major (Ridley) Moss) or narrow-leaf anacharis (Egeria najas Planchon). The registration of the bleaching herbicide fluridone in the mid 1980s for whole-lake and large-scale management stimulated numerous lines of research involving reduction of use rates, plant selectivity, residue monitoring, and impacts on fisheries. In addition to numerous advances, the specificity of fluridone for a single plant enzyme led to the first documented case of herbicide resistance in aquatic plant management. The resistance of hydrilla to fluridone has stimulated a renewed interest by industry and others in the registration of alternative modes of action for aquatic use. These newer chemistries tend to be enzyme-specific compounds with favorable non-target toxicity profiles. Registration efforts have been facilitated by increased cooperation between key federal government agencies that have aquatic weed control and research responsibilities, and regulators within the U.S. Environmental Protection Agency (USEPA). We reviewed past and current research efforts to identify areas in need of further investigation and to establish priorities for future research directions in chemical management of submersed plants. The priorities we identified include: (A) improving methods for evaluating non-target impacts of herbicides with an emphasis on threatened and endangered species, or species of special concern; (B) improving herbicide performance in flowing-water environments, including irrigation canals; (C) screening and developing new herbicides to supplement fluridone for large-scale or whole-lake management approaches; (D) screening and developing new organic algaecides to supplement the use of copper-based compounds; (E) developing risk assessment tools to educate the public on the risks of invasive species and chemical management options; (F) increasing cooperative research with ecologists and fisheries scientists to evaluate the long-term impacts of invasive species introductions and herbicide programs on native plant assemblages, water quality, and fish populations; and (G) improving the integration of chemical control technology with other aquatic plant management disciplines. While circumstances may dictate setting new priorities or dropping current ones, the list we have generated represents our vision of the needs that will require the greatest focus over the next several years.

Ernst Florens Friedrich Chladni (1756-1827) and the origins of modern meteorite research

NASA Astrophysics Data System (ADS)

Marvin, Ursula B.

1996-09-01

In 1794, Ernst F. F. Chladni published a 63-page book Über den Ursprung der von Pallas gefundenen und anderer ihr änlicher Eisenmassen und über einige damit in Verbindung stehende Naturerscheinungen in which he proposed that meteor-stones and iron masses enter the atmosphere from cosmic space and form fireballs as they plunge to Earth. These ideas violated two strongly held contemporary beliefs: (1) fragments of rock and metal do not fall from the sky, and (2) no small bodies exist in space beyond the Moon. From the beginning, Chladni was severely criticised for basing his hypotheses on historical eyewitness reports of falls which others regarded as folk tales and for taking gross liberties with the laws of physics. Eight years later, the study of fallen stones and irons was established as a valid field of investigation. Today, some scholars credit Chladni with founding meteoritics as a science; others regard his contributions as scarcely worthy of mention. Writings by his contemporaries suggest that Chladni's book alone would not have led to changes of prevailing theories; thus, he narrowly escaped the fate of those scientists who propose valid hypotheses prematurely. However between 1794 and 1798, four falls of stones were witnessed and widely publicized. There followed a series of epoch-making analyses of fallen stones and "native irons" by the chemist Edward C. Howard and the mineralogist Jacques-Louis de Bournon. They showed that all the stones were much alike in texture and composition but significantly different from the Earth's known crustal rocks. Of primary importance was Howard's discovery of nickel in the irons and the metal grains of the stones. This linked the two as belonging to the same natural phenomenon. The chemical results, published in 1802 February, persuaded leading scientists in England, France, and Germany that bodies fall from the sky. Within a few months, chemists in France reported similar results and a new field of study was inaugurated internationally—although opposition lingered on until 1803 April, when nearly 3,000 stones fell at L'Aigle in Normandy and transformed the last skeptics into believers. Chladni immediately received full credit for his hypothesis of falls, but decades passed before his linking of falling bodies with fireballs received general acceptance. His hypothesis of their origin met with strong resistance from those who argued that stones formed within the Earth's atmosphere or were ejected by lunar volcanoes. After 1860, when both of these hypotheses were abandoned, there followed a century of debate between proponents of an interstellar vs. a planetary origin. Not until the 1950s did conclusive evidence of their elliptical orbits establish meteorite parent bodies as members of the solar system. Thus, nearly 200 years passed before the questions of origin that Chladni raised finally were resolved.

Gravity effects on endogenous movements

NASA Astrophysics Data System (ADS)

Johnsson, Anders; Antonsen, Frank

Gravity effects on endogenous movements A. Johnsson * and F. Antonsen *+ * Department of Physics, Norwegian University of Science and Technology,NO-7491, Trond-heim, Norway, E-mail: anders.johnsson@ntnu.no + Present address: Statoil Research Center Trondheim, NO-7005, Trondheim, Norway Circumnutations in stems/shoots exist in many plants and often consists of more or less regular helical movements around the plumb line under Earth conditions. Recent results on circumnu-tations of Arabidopsis in space (Johnsson et al. 2009) showed that minute amplitude oscilla-tions exist in weightlessness, but that centripetal acceleration (mimicking the gravity) amplified and/or created large amplitude oscillations. Fundamental mechanisms underlying these results will be discussed by modeling the plant tissue as a cylinder of cells coupled together. As a starting point we have modeled (Antonsen 1998) standing waves on a ring of biological cells, as first discussed in a classical paper (Turing 1952). If the coupled cells can change their water content, an `extension' wave could move around the ring. We have studied several, stacked rings of cells coupled into a cylinder that together represent a cylindrical plant tissue. Waves of extensions travelling around the cylinder could then represent the observable circumnutations. The coupling between cells can be due to cell-to-cell diffusion, or to transport via channels, and the coupling can be modeled to vary in both longitudinal and transversal direction of the cylinder. The results from ISS experiments indicate that this cylindrical model of coupled cells should be able to 1) show self-sustained oscillations without the impact of gravity (being en-dogenous) and 2) show how an environmental factor like gravity can amplify or generate the oscillatory movements. Gravity has been introduced in the model by a negative, time-delayed feed-back transport across the cylinder. This represents the physiological reactions to acceler-ation stimulations (gravitropism reactions). Such a negative feedback can account for gravity initiated transport, resulting in lateral water transport and overall movements. The simulation results indicate that self-sustained oscillations can occur on such a cylinder of cells. It will also be demonstrated that the introduction of feedback in the model results in longer circum-nutation periods. It will be discussed how this generic modeling approach could be applied to discuss oscillatory plant movements in general and how other environmental factors, as for instance light gradients, could couple to the self-sustained movements. The oscillations require weightlessness for proper investigations. References: Antonsen F.: Biophysical studies of plant growth movements in microgravity and under 1 g conditions. PhD thesis, Norwegian University of Science and Technology 1998. Johnsson A., Solheim BGB, Iversen T.-H.: Gravity amplifies and microgravity decreases cir-cumnutations in Arabidopsis thaliana stems: results from a space experiment.-New Phytologist 182: 621-629. 2009. Turing AM.: The chemical basis for morphogenesis.-Phil Trans. R. Soc. London Ser B237:37 -72. 1952.

THE RELIABILITY OF HAND-WRITTEN AND COMPUTERISED RECORDS OF BIRTH DATA COLLECTED AT BARAGWANATH HOSPITAL IN SOWETO

PubMed Central

Ellison, GTH; Richter, LM; de Wet, T; Harris, HE; Griesel, RD; McIntyre, JA

2007-01-01

This study examined the reliability of hand-written and computerised records of birth data collected during the Birth to Ten study at Baragwanath Hospital in Soweto. The reliability of record-keeping in hand-written obstetric and neonatal files was assessed by comparing duplicate records of six different variables abstracted from six different sections in these files. The reliability of computerised record-keeping was assessed by comparing the original hand-written record of each variable with records contained in the hospital’s computerised database. These data sets displayed similar levels of reliability which suggests that similar errors occurred when data were transcribed from one section of the files to the next, and from these files to the computerised database. In both sets of records reliability was highest for the categorical variable infant sex, and for those continuous variables (such as maternal age and gravidity) recorded with unambiguous units. Reliability was lower for continuous variables that could be recorded with different levels of precision (such as birth weight), those that were occasionally measured more than once, and those that could be measured using more than one measurement technique (such as gestational age). Reducing the number of times records are transcribed, categorising continuous variables, and standardising the techniques used for measuring and recording variables would improve the reliability of both hand-written and computerised data sets. OPSOMMING In hierdie studie is die betroubaarheid van handgeskrewe en gerekenariseerde rekords van ge boortedata ondersoek, wat versamel is gedurende die ‘Birth to Ten’ -studie aan die Baragwanath hospitaal in Soweto. Die betroubaarheid van handgeskrewe verloskundige en pasgeboortelike rekords is beoordeel deur duplikaatrekords op ses verskillende verander likes te vergelyk, wat onttrek is uit ses verskillende dele van die betrokke lêers. Die gerekenariseerde rekords se betroubaarheid is beoordeel deur die oorspronklike geskrewe rekord van elke veranderlike te vergelyk met rekords wat beskikbaar is in die hospitaal se gerekenariseerde databasis Hierdie datastelle her vergelykbare vlakke van betroubaarheid getoon, waaruit afgelei kan word dat soortgelyke foute voorkom warmeer data oorgeplaas word vaneen deeivan ’n lêer na ’n ander, en vanaf die lêer na die gerekenariseerde databasis. In albei stelle rekords was die betroubaarheid die hoogste vir die kategoriese veranderlike suigeling se geslag, en vir daardie kontinue veranderlikes (soos moeder se ouderdom en gravida) wat in terme van ondubbelsinmge eenhede gekodeer kan word. Kontinue veranderlikes wat op wisselende vlakke van akkuratheid gemeet word (soos gewig met geboorte), veranderlikes wat soms meer as een keer gemeet is, en veranderlikes wat voigens meer as een metingstegniek bepaal is (soos draagtydsouderdom), was minder betroubaar Deur die aantal kere wat rekords oorgeskryf moet word te verminder, kontinue veranderlikes tat kategoriese veranderlikes te wysig. en tegnieke vir meting en aantekening van veranderlikes te standardiseer, kan die betroubaarheid van sowel handgeskrewe as gerekenariseerde datastelle verbeter word. PMID:9287552

Dynamics of vortices in complex wakes: Modeling, analysis, and experiments

NASA Astrophysics Data System (ADS)

Basu, Saikat

The thesis develops singly-periodic mathematical models for complex laminar wakes which are formed behind vortex-shedding bluff bodies. These wake structures exhibit a variety of patterns as the bodies oscillate or are in close proximity of one another. The most well-known formation comprises two counter-rotating vortices in each shedding cycle and is popularly known as the von Karman vortex street. Of the more complex configurations, as a specific example, this thesis investigates one of the most commonly occurring wake arrangements, which consists of two pairs of vortices in each shedding period. The paired vortices are, in general, counter-rotating and belong to a more general definition of the 2P mode, which involves periodic release of four vortices into the flow. The 2P arrangement can, primarily, be sub-classed into two types: one with a symmetric orientation of the two vortex pairs about the streamwise direction in a periodic domain and the other in which the two vortex pairs per period are placed in a staggered geometry about the wake centerline. The thesis explores the governing dynamics of such wakes and characterizes the corresponding relative vortex motion. In general, for both the symmetric as well as the staggered four vortex periodic arrangements, the thesis develops two-dimensional potential flow models (consisting of an integrable Hamiltonian system of point vortices) that consider spatially periodic arrays of four vortices with their strengths being +/-Gamma1 and +/-Gamma2. Vortex formations observed in the experiments inspire the assumed spatial symmetry. The models demonstrate a number of dynamic modes that are classified using a bifurcation analysis of the phase space topology, consisting of level curves of the Hamiltonian. Despite the vortex strengths in each pair being unequal in magnitude, some initial conditions lead to relative equilibrium when the vortex configuration moves with invariant size and shape. The scaled comparisons of the model results with experiments conducted in a owing soap film with an airfoil, which was imparted with forced oscillations, are satisfactory and validate the reduced order modeling framework. The experiments have been performed by a collaborator group at the Department of Physics and Fluid Dynamics at the Technical University of Denmark (DTU), led by Dr. Anders Andersen. Similar experiments have also been run at Virginia Tech as part of this dissertation and the preliminary results are included in this treatise. The thesis also employs the same dynamical systems techniques, which have been applied to study the 2P regime dynamics, to develop a mathematical model for the P+S mode vortex wakes, with three vortices present in each shedding cycle. The model results have also been compared favorably with an experiment and the predictions regarding the vortex circulation data match well with the previous results from literature. Finally, the thesis introduces a novel concept of clean and renewable energy extraction from vortex-induced vibrations of bluff bodies. The slow-moving currents in the off-shore marine environments and riverine flows are beyond the operational capabilities of the more established hydrokinetic energy converters and the discussed technology promises to be a significant tool to generate useful power from these copiously available but previously untapped sources.

The Epital Care Model: A New Person-Centered Model of Technology-Enabled Integrated Care for People With Long Term Conditions.

PubMed

Phanareth, Klaus; Vingtoft, Søren; Christensen, Anders Skovbo; Nielsen, Jakob Sylvest; Svenstrup, Jørgen; Berntsen, Gro Karine Rosvold; Newman, Stanton Peter; Kayser, Lars

2017-01-16

There is worldwide recognition that the future provision of health care requires a reorganization of provision of care, with increased empowerment and engagement of patients, along with skilled health professionals delivering services that are coordinated across sectors and organizations that provide health care. Technology may be a way to enable the creation of a coherent, cocreative, person-centered method to provide health care for individuals with one or more long-term conditions (LTCs). It remains to be determined how a new care model can be introduced that supports the intentions of the World Health Organization (WHO) to have integrated people-centered care. To design, pilot, and test feasibility of a model of health care for people with LTCs based on a cocreative, iterative, and stepwise process in a way that recognizes the need for person-centered care, and embraces the use of digital technology. The overall research method was inspired by action research and used an agile, iterative approach. In 2012, a living lab was established in a Danish municipality which allowed for the freedom of redesigning health care processes. As the first step, a wide group of stakeholders was gathered to create a layout for the reorganization of services and development of technology, based on established principles for innovative management of people with chronic conditions. The next three steps were (1) a proof of concept in 2012, (2) a pilot study, and (3) a feasibility study from 2013 to 2015, in which a total of 93 chronic obstructive pulmonary disease (COPD) patients were enrolled. Citizens were provided a tablet-based solution for remote follow-up and communication purposes, and access to a 24/7 response and coordination center that coordinated both virtual and face-to-face support for COPD management. In step five the initial model was extended with elements that support continuity of care. Beginning in the autumn of 2013, 1102 frail elderly individuals were included and offered two additional services: an outgoing acute medical team and a local subacute bed function. Based on the findings from the iterative process, and evolving technology and workflow solutions, we propose a robust and feasible model that can provide a framework for developing solutions to support an active life with one or more LTCs. The resulting Epital Care Model (ECM) consists of six stages, and serves as a template for how a digitally-enhanced health service can be provided based on patients' medical needs. The model is designed to be a proactive, preventive, and monitoring health care system that involves individuals in the management of their own health conditions. The ECM is in accordance with WHO's framework for integrated people-centered health services, and may serve as a framework for the development of new technologies and provide a template for future reorganization. ©Klaus Phanareth, Søren Vingtoft, Anders Skovbo Christensen, Jakob Sylvest Nielsen, Jørgen Svenstrup, Gro Karine Rosvold Berntsen, Stanton Peter Newman, Lars Kayser. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 16.01.2017.

Modeling populations of rotationally mixed massive stars

NASA Astrophysics Data System (ADS)

Brott, I.

2011-02-01

Massive stars can be considered as cosmic engines. With their high luminosities, strong stellar winds and violent deaths they drive the evolution of galaxies through-out the history of the universe. Despite the importance of massive stars, their evolution is still poorly understood. Two major issues have plagued evolutionary models of massive stars until today: mixing and mass loss On the main sequence, the effects of mass loss remain limited in the considered mass and metallicity range, this thesis concentrates on the role of mixing in massive stars. This thesis approaches this problem just on the cross road between observations and simulations. The main question: Do evolutionary models of single stars, accounting for the effects of rotation, reproduce the observed properties of real stars. In particular we are interested if the evolutionary models can reproduce the surface abundance changes during the main-sequence phase. To constrain our models we build a population synthesis model for the sample of the VLT-FLAMES Survey of Massive stars, for which star-formation history and rotational velocity distribution are well constrained. We consider the four main regions of the Hunter diagram. Nitrogen un-enriched slow rotators and nitrogen enriched fast rotators that are predicted by theory. Nitrogen enriched slow rotators and nitrogen unenriched fast rotators that are not predicted by our model. We conclude that currently these comparisons are not sufficient to verify the theory of rotational mixing. Physical processes in addition to rotational mixing appear necessary to explain the stars in the later two regions. The chapters of this Thesis have been published in the following Journals: Ch. 2: ``Rotating Massive Main-Sequence Stars I: Grids of Evolutionary Models and Isochrones'', I. Brott, S. E. de Mink, M. Cantiello, N. Langer, A. de Koter, C. J. Evans, I. Hunter, C. Trundle, J.S. Vink submitted to Astronomy & Astrop hysics Ch. 3: ``The VLT-FLAMES Survey of Massive Stars: Rotation and Nitrogen Enrichment as the Key to Understanding Massive Star Evolution'', I.Hunter, I.Brott, D.J. Lennon, N. Langer, C. Trundle, A. de Koter, C.J. Evans and R.S.I. Ryans The Astrophysical Journal, 2008, 676, L29-L32 Ch. 4: ``The VLT-FLAMES Survey of Massive Stars: Constraints on Stellar Evolution from the Chemical Compositions of Rapidly Rotating Galactic and Magellanic Cloud B-type Stars '', I. Hunter, I. Brott, N. Langer, D.J. Lennon, P.L. Dufton, I.D. Howarth R.S.I. Ryan, C. Trundle, C. Evans, A. de Koter and S.J. Smartt Published in Astronomy & Astropysics, 2009, 496, 841- 853 Ch. 5: ``Rotating Massive Main-Sequence Stars II: Simulating a Population of LMC early B-type Stars as a Test of Rotational Mixing '', I. Brott, C. J. Evans, I. Hunter, A. de Koter, N. Langer, P. L. Dufton, M. Cantiello, C. Trundle, D. J. Lennon, S.E. de Mink, S.-C. Yoon, P. Anders submitted to Astronomy & Astrophysics Ch 6: ``The Nature of B Supergiants: Clues From a Steep Drop in Rotation Rates at 22 000 K - The possibility of Bi-stability braking'', Jorick S. Vink, I. Brott, G. Graefener, N. Langer, A. de Koter, D.J. Lennon Astronomy & Astrophysics, 2010, 512, L7

How can we constrain the amount of heat producing elements in the interior of Mars?

NASA Astrophysics Data System (ADS)

Grott, M.; Plesa, A.; Breuer, D.

2013-12-01

The InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission to be launched in 2016 will study Mars' deep interior and help improving our knowledge about the interior structure and the thermal evolution of the planet - the latter is also directly linked to its volcanic history and atmospheric evolution. Measurements planned with the two main instruments, SEIS (Seismic Experiment for Interior Structure) and HP3 (Heat Flow and Physical Properties Package) aim to constrain the main structure of the planet, i.e. core, mantle and crust as well as the rate at which the planet loses the interior heat over its surface. Since the surface heat flow depends on the amount of radiogenic heat elements (HPE) present in the interior, it offers a measurable quantity which could constrain the heat budget. Being the principal agent regulating the heat budget which in turn influences partial melting in the interior, crustal and atmospheric evolution, the heat producing elements have a major impact on the entire the present temperature thermal history of the planet. To constrain the radiogenic heat elements of the planet from the surface heat flow is possible assuming that the urey number of the planet, which describes the contribution of internal heat production to the surface heat loss, is known. We have tested this assumption by calculating the thermal evolution of the planet with fully dynamical numerical simulations and by comparing the obtained present-day urey number for a set of different models/parameters (Fig. 1). For one-plate planets like Mars, numerical models show - in contrast to models for the Earth, where plate tectonics play a major role adding more complexity to the system - that the urey ratio is mainly sensitive to two effects: the efficiency of cooling due to the temperature-dependence of the viscosity and the mean half-life time of the long lived radiogenic isotopes. The temperature-dependence of the viscosity results in the so-called thermostat effect regulating the interior temperature such that the present-day temperatures are independent of the initial temperature distribution. If the thermostat effect is efficient as we show for the assumed Martian mantle rheology, and if the system is not dominated by radioactive isotopes like Thorium with a half-life much longer than the age of the planet as in the model of [3], all numerical simulations show similar today's values for the urey number (Fig. 1). Knowing the surface heat loss from the upcoming heat flow measurements planned for the InSight mission, one can distinguish then between different radiogenic heat source models [1, 2, 3, 4]. REFERENCES [1] Wänke et al., 94; [2] Lodders & Fegley, 97; [3] Morgan & Anders, 79; [4] Treiman et al., 86 Fig. 1: a) the influence of the reference viscosity and initial upper thermal boundary layer (TBL) on the urey ratio using HPE density from [1]; b) different models for HPE density; c) the urey ratio for different HPE models and 1e22 Pa s reference viscosity.

Nitrogen in Interplanetary Dust Particles

NASA Astrophysics Data System (ADS)

Keller, L. P.; Thomas, K. L.; Bradley, J. P.; McKay, D. S.

1995-09-01

Little is known about the abundance, distribution and chemical state of nitrogen in IDPs with the exceptions of the isotopic enrichment in 15N displayed by many particles [1-3], and the inferred association of nitrogen with polyaromatic hydrocarbons in some IDPs [4]. Like carbon, nitrogen is strongly fractionated among meteoritic materials and it is well known that the most primitive carbon-rich meteorites also tend to have high nitrogen abundances [5]. Nitrogen-bearing compounds are also a significant component of the carbonaceous material (CHON particles) sampled during the comet Halley encounter [e.g. 6]. We describe here the first reported detection and location of nitrogen concentrations in several IDPs using electron energy-loss spectroscopy. Three chondritic, anhydrous IDPs (L2011R11, L2008F13, and a fragment from L2006, cluster 14) were embedded in sulfur [7] and tranmission electron microscope (TEM) specimens were prepared by ultramicrotomy. The IDP thin sections were placed on copper TEM grids with SiO thin film substrates and analyzed using a JEOL 2010 TEM equipped with a thin-window energy-dispersive X-ray detector and a Gatan 666 parallel EELS spectrometer. We also analyzed W7027H14, a carbon-rich, chondritic-porous IDP that was embedded in epoxy. The EELS data from carbon-rich amorphous regions of the analyzed IDPs typically show a small, but distinct nitrogen edge at ~400 eV (Figure 1). The nitrogen is not homogeneously distributed in the carbonaceous material in the four IDPs analyzed to date, but occurs in "hot spots". However, these "hot spots" do not appear to be associated with a distinct N-bearing mineral (e.g. nitrides); the nitrogen is indigenous to the carbonaceous material in these IDPs. Although the quantitative N analyses using EELS are still in progress, the preliminary data from one IDP (L2011R11) indicates an upper N/C atom ratio of ~0.1, which is comparable to the chondritic value (N/C ~0.08, [8]). It should be noted however, that the SEM/EDX analysis of L2011R11 shows that it has a bulk C abundance of ~9 wt.% (nearly 3X the CI abundance), which indicates that, for this particle, the absolute N abundance is also enriched above CI levels. EELS is well-suited for this analysis because of its sensitivity for light element detection and quantification, and also for the additional data on bonding environment that can be deduced from the near-edge structure. References: [1] Stadermann F. J. et al. (1989) Meteoritics, 24, 327. [2] Stadermann F. J. et al. (1990) LPS XXI, 1190. [3] Messenger S. et al., this volume. [4] Clemett S. J. et al. (1993) Science, 262, 721. [5] Kerridge J. F. (1985) GCA, 49, 1707. [6] Fomenkova M. N. et al. (1994) GCA, 58, 4503. [7] Bradley J. P. et al. (1993) LPS XXIV, 173. [8] Anders E. and Grevesse N. (1989) GCA, 53, 197. FIGURE 1. Electron energy-loss data from carbonaceous material in L2011R11 (a pyroxene-rich, anhydrous IDP) showing detectable nitrogen associated with carbon. The lower spectrum is a 2nd difference spectrum of the raw data.

The End Pleistocene Extinction Event - What Caused It?

NASA Astrophysics Data System (ADS)

Becker, L.; Poreda, R.; Kennett, J.; West, A.; Wolbach, W.

2007-05-01

It is well established that the last catastrophic faunal extinction in the geologic past coincided with the end of the Pleistocene during the deglaciation between the last glacial episode and the present Holocene interglacial. The cause of this extinction has been debated for many years but remains highly controversial in part because of limitations of available data, but also because the two major hypotheses that have been long invoked, climate change and human overhunting, have continued to present significant problems. Recently, Firestone et al. [1] have reported strong evidence for an extraterrestrial (ET) impact including peak abundances of metallic microspherules and magnetic grains with elevated iridium, glass-like carbon, carbon microspherules, soot and charcoal in a carbon-rich black layer dating close to ~12.9 ka (referred to as Younger Dryas Black Layer or YDB) in numerous terminal Clovis-age sites across North America. To assess the YDB impact hypothesis and its potential effects on the megafauna and humans in North America [2-4], we have analyzed several well-dated suites of samples in search of fullerenes with ET noble gases and other impact debris (e.g. microspherules). These sites include Daisy Cave (DC) on California's San Miguel Island, Murray Springs (MS) in Arizona and Blackwater Draw (BWD) in New Mexico, all well known previously described archaeological and paleontological sites, with established chronologies spanning the YDB (~12.9 k) [5-7]. To further assess the environmental effects of the impact on the Pleistocene fauna and human activity, we examined the YDB layer at each of these locations for evidence of wildfires triggered by the ET event. If there were wildfires, a group of high molecular weight aromatic compounds or polycyclic aromatic hydrocarbons (PAHs) should be present in the associated soot and charcoal material within the YDB. By examining the distributions of the PAHs, the source of these compounds, wildfire or human activity, can be determined. The recognition of global wildfires at the time of the K/T impact event was first proposed based on the presence of elemental carbon (mainly soot) associated with ET tracers in the boundary layer [8-10]. Soot produced by severe wildfires at the YDB would have severely affected the ecological niches, reduced primary productivity, eliminated food sources and added to the effects of the ejecta cloud [8]. Here, we present our evidence in support of an ET impact and its effects on the environment at the YDB and compare these results to other well-known impact events in the geologic record. [1] Firestone et al. (2006) Proceeding of the National Academies of Science (submitted). [2] Martin, P.S. Twilight of the Mammoths Ice Age Extinctions and the Rewilding of America. University of California Press, Berkeley 250 pp. (2005). [3] Haynes, C.V. (2002) World Archeology 33,391-416. [4] Grayson, D. K. and Meltzer, D.J. (2002) Journal of World Prehistory 16, 313-359. [5] Erlandson, J.M. et al. (1996) Radiocarbon 38,355-373. [6] Haynes, C.V.et al., (1999) Geoarcheology: An International Journal, 14, 455-470.[7] Tayler, R.E., Haynes, C.V. and Stuvier, M. (1996) Antiquity 70, 515-525. [8] Wolbach, W.S., Lewis, R.S. and Anders, L.E. (1985) Science 230,167-170. [9] Wolbach et al. (1988) Nature 334,57-669. [10] Venkatesan, M.I. and Dahl, J. (1989) Nature 338,57-60.

Traditional application of slates in Uruguay

NASA Astrophysics Data System (ADS)

Morales Demarco, Manuela; Cardenes Van den Eynde, Víctor

2017-04-01

Commercial slates in Uruguay are represented by dolomitic and pelitic slates, which are known in the local market with the generic name of "piedra laja". The dolomitic slates, or more precisely the "slaty dolomitic semipelites" and "slaty dolomitic metacarbonate rocks" (following the nomenclature of the British Geological Survey for metamorphic rocks, Robertson 1999), dominates the production since 1960. The mining started in a quarry called "Libro Gigante", which means "giant book" in Spanish, as the slaty cleavage of these rocks is almost vertical, which resembles a book when looked from far away. These slates integrate the Lavalleja Group, a unit that comprises the schist belt of the Neoproterozoic Dom Feliciano Belt that crops out in south-eastern Uruguay. According to Morales Demarco et al (2013), there are two active slate mining districts in this region: the northern, called "Arroyo Minas Viejas Mining District", from where light grey, light and dark green and green-red slate varieties are mined, and the southern called "Arroyo Mataojo Mining District" and where only dark grey slates are extracted. Few kilometres eastern from these districts, and still in Lavalleja Group, a quarry of slaty dolomitic pelite is found with sporadic production. Far to the east, the slaty muscovitic pelites of Rocha Group are mined from one quarry in "Puntas del Chafalote". The traditional applications of these slates in the country are as façade cladding and floor slabs, both indoor and outdoor. The potential use of the dolomitic slates as roofing slates has been investigated and discarded by Morales Demarco et al (2013), as the slabs resulting from splitting are too thick (0.5 to 2 cm) and thus too heavy for this application. The parameter that controls the fissility of slates is the mass value (Bentz and Martini, 1968; DIN EN 12326-2, 2000) and is very important to determine their potential applications. It takes into account the number of mica layers per mm and the average width of these mica layers, being the former determinant for roofing slates, as according to Wagner (2007) slates with a number of mica layers per mm lower than 40 are not suitable as roofing and façade slates. All dolomitic slates have mass values below 40 (Morales Demarco et al, 2013), but this parameter has not been evaluated for the pelitic slates of Uruguay, and thus it remains unknown the potential of these rocks as roofing slates. Bentz A, Martini HJ (1968) Lehrbuch der Angewandten Geologie, Band 2, 1: Methoden zur Erforschung der Lagerstätten von Erzen, Kohle, Erdöl, Salzen, Industrie-Mineralen und Steinen und Erden. Sttutgart (Enke) DIN EN 12326-2 (2000) Schiefer und andere Natursteinprodukte für überlappende Dachdeckungen und Außenwandbekleidungen. Teil 2: Prüfverfahren. DIN Deutsches Institut für Normung e.V., Beuth, Berlin Morales Demarco M, Oyhantçabal P, Stein K-J, Siegesmund S (2013) Dolomitic slates from Uruguay: petrophysical and petromechanical characterization and deposit evaluation. Environ Earth Sci 69: 1361. doi:10.1007/s12665-012-1921-7 Wagner W (2007) Grundlagen für die Prüfung von Dach- und Wandschiefern. Z dt Ges Geowiss 158(4):785-805

Airborne laser-spark for ambient desorption/ionisation.

PubMed

Bierstedt, Andreas; Riedel, Jens

A novel direct sampling ionisation scheme for ambient mass spectrometry is presented. Desorption and ionisation are achieved by a quasi-continuous laser induced plasma in air. Since there are no solid or liquid electrodes involved the ion source does not suffer from chemical interferences or fatigue originating from erosive burning or from electrode consumption. The overall plasma maintains electro-neutrality, minimising charge effects and accompanying long term drift of the charged particles trajectories. In the airborne plasma approach the ambient air not only serves as the plasma medium but at the same time also slows down the nascent ions via collisional cooling. Ionisation of the analyte molecules does not occur in the plasma itself but is induced by interaction with nascent ionic fragments, electrons and/or far ultraviolet photons in the plasma vicinity. At each individual air-spark an audible shockwave is formed, providing new reactive species, which expands concentrically and, thus, prevents direct contact of the analyte with the hot region inside the plasma itself. As a consequence the interaction volume between plasma and analyte does not exceed the threshold temperature for thermal dissociation or fragmentation. Experimentally this indirect ionisation scheme is demonstrated to be widely unspecific to the chemical nature of the analyte and to hardly result in any fragmentation of the studied molecules. A vast ensemble of different test analytes including polar and non-polar hydrocarbons, sugars, low mass active ingredients of pharmaceuticals as well as natural biomolecules in food samples directly out of their complex matrices could be shown to yield easily accessible yet meaningful spectra. Since the plasma medium is humid air, the chemical reaction mechanism of the ionisation is likely to be similar to other ambient ionisation techniques. Wir stellen hier eine neue Ionisationsmethode für die Umgebungsionisation (ambient ionisation) vor. Sowohl die Desorption als auch die Ionisation erfolgen hierbei durch ein laserbetriebenes Luftplasma. Die Abwesenheit fester oder flüssiger Elektroden hat zur Folge, dass die Methode weder unter chemischen Interferenzen noch unter Verschleiß durch Korrosionsbrand oder abgetragenes Elektrodenmaterial leidet. Insgesamt betrachtet herrscht in dem Plasma Elektroneutralität, wodurch Aufladungseffekte minimiert werden, die andernfalls zu einer langfristigenÄderung der Flugbahnen von Ionen während der Experimente führen kann. In dem Ansatz eine freischwebende Luftentladung bei Atmosphärendruck zu verwenden agiert die Luft nicht nur als Plasmamedium sondert dient zusätzlich als Badgas für die stoßinduzierte Kühlung der entstehenden Ionen. Die Ionisierung der Analytmoleküle erfolgt nicht unmittelbar im Plasma sondern in dessen direkter Umgebung durch Wechselwirkung mit freigesetzten ionischen Luftspezies, freien Elektronen oder Photonen im kurzwelligen ultravioletten Bereich. Jede Laserentladung erzeugt eine hörbare Stoßwelle, in welcher neu produzierte reaktive Spezies freigesetzt werden, welche sich konzentrisch ausbreiten, so dass eine Diffusion der Analytmoleküle ins heiße Innere des Plasmas verhindert wird. Daraus folgt, dass im Interaktionsvolumen zwischen Plasma und Analyt der Temperaturgrenzwert für eine thermische Dissoziation oder Fragmentierung der Moleküle nicht überschritten wird. Experimentell konnte belegt werden, dass das vorgestellte Ionisierungsschema sehr unselektiv bezüglich der chemischen Analytklasse ist und kaum Fragmentierungsprodukte beobachtet werden können. Messungen einer breitgefächerten Auswahl unterschiedlicher Testsubstanzen, wie beispielsweise polarer und unpolarer Kohlenwasserstoffe, Zuckern, niedermolekularer pharmazeutischer Wirkstoffe, sowie natürlicher Biomoleküle in Lebensmittelproben unmittelbar aus ihren komplexen Matrizes, führten zu aussagekräftigen Massenspektren. Zumal das Lasermedium feuchte Luft ist, scheint der Reaktionsmechanismus dem anderer Atmosphärendruckionisierungsmethoden zuähneln.

Millennial oscillations in greenland dust and Eurasian Aeolian records - a paleosol-loess perspective (Hans Oeschger Medal Lecture)

NASA Astrophysics Data System (ADS)

Rousseau, Denis-Didier

2017-04-01

Considerable interest is brought on the abrupt climate changes that punctuated the last glacial period (˜110.6-14.62 ka). Originating in the North-Atlantic area, they have been recorded in ice, marine and terrestrial records all over the world, and especially in the Northern Hemisphere, with various environmental implications. The ice-core records, of increasingly high resolution, allow specifying more precisely the timing of these abrupt changes, which have occurred within intervals equivalent to present human generations. The continental records have been mainly interpreted so far in terms of temperature, precipitation or vegetation changes between the relatively warm ("Greenland Interstadial" - GI) and the cold ("Greenland Stadial" - GS) North-Atlantic climate phases. In this presentation records from Greenland ice and northwestern European eolian deposits are compared in order to establish a link between GI and the soil development in European mid-latitudes, as recorded in loess sequences. For the different types of observed paleosols, the precise correlation with the Greenland records is applied to propose estimates of the maximum time lapses needed to achieve the different degrees of maturation and development. To identify these time lapses more precisely, two independent ice-core records are compared: δ180 and dust concentration, indicating variations of temperature and atmospheric dustiness respectively in the Greenland area. This method slightly differs from the definition of a GI event duration applied in other studies where the sharp end of the δ18O decrease gives the end of a GI. The same methodology is applied to both records (i.e., the GI last from the beginning of the abrupt δ18O increase or dust concentration decrease until when δ18O or dust reach again their initial value) determined both visually and algorithmically, and compare them to GI published estimates. Focusing on the eolian/dust intervals, the analysis of δ18O and dust in the Greenland ice cores, and a critical study of their source variations, reconciles these records with those observed on the Eurasian continent. This allows demonstrating the link between European and Chinese loess sequences, dust records in Greenland, and variations of the North Atlantic sea ice extent. The sources of the emitted and transported dust material are variable and relate to different environments corresponding to present desert areas in Asia, but also hidden regions related to lower sea level stands, dry rivers, or zones close to the frontal moraines of the main Northern Hemisphere ice sheets in Europe. As a conclusion of this presentation, I address the short term past climatic changes as preserved in the continental eolian records, in line with the Hans Oeschger medal description. Furthermore one can anticipate such study to be at the origin of more sophisticated and elaborated investigations of millennial and sub-millennial continental climate variability on the Northern Hemisphere. The overview presented during this presentation would not have been possible without the help and close collaboration of many colleagues among whom are Niklas BOERS, Adriana SIMA, Anders SVENSSON, Matthias BIGLER, France LAGROIX, Samuel TAYLOR, Pierre ANTOINE, Christine HATTE, Michael GHIL, George KUKLA, Sigfus JOHNSEN, Markus FUCHS, Andreas LANG, Gilles BERGAMETTI, Beatrice MARTICORENA and Ludwig ZOELLER.

Nordic exchange of students and climate change.

NASA Astrophysics Data System (ADS)

Thomsson, A.

2012-04-01

Since the end of 2010 and until the summer of 2011 two upper secondary schools in Höyanger, Norway and Ronneby, Sweden had the possibility to take part in a project called Nordplus junior. The main aims of the program are: • To promote Nordic languages and culture and mutual Nordic-Baltic linguistic and cultural understanding. • To contribute to the development of quality and innovation in the educational systems for life-long learning in the participating countries by means of educational cooperation, development projects, exchanges and networking. • To support, develop, draw benefit from and spread innovative products and processes in education through systematic exchange of experiences and best practice. • To strengthen and develop Nordic educational cooperation and contribute to the establishment of a Nordic-Baltic educational area. The students did research on climate change and the impact on local and regional areas. Many questions had to be answered, giving an explanation to what happens if the climate changes. Questions related to Höyanger, Norway What happens to life in Norwegian fiords? Which attitudes do youngsters and adults have about climate change and what actions do they take? What does a rise in sea level mean for Höyanger? How are different tourist attractions affected in western Norway? Questions related to Ronneby, Sweden How is the regional fauna and flora affected? What will happen to agriculture and forestry? What do adults and youngsters know about consequences of a possible climate change? What happens to the people of Ronneby if the sea level rises? Are there any positive outcomes if the climate changes? Conclusions In Norwegian fiords there could be benefits because fish are growing faster in the winter because of an increased temperature. At the same time there could be an imbalance in the ecosystem because of a change in the living ranges of different species. Most of the young boys and girls in Höyanger, Norway were consistent with their attitudes towards the environment. In the survey of adults (Höyanger) women between 50-60 years old were the ones that were friendliest towards the environment. The students of Sweden (Ronneby) believe both young Norwegian and Swedish people are well educated in climate changes issues. A rise in the sea level will have serious impact on both Ronneby and Höyanger. In Höyanger people could lose their jobs and landslides could take place. In Ronneby, ground water could be polluted by salt and sewage water. In Ronneby parks would be flooded and restrictions on building new houses below 2.2 meters above sea level would be enforced. In Bergen, Norway, the Hanseatic buildings will be flooded, there will be huge economic problems, new roads have to be built etc. The regional flora and fauna in Sweden will move northwards and new species will enter from Central Europe. The vegetation season will be longer and the crops will benefit from a higher carbon dioxide concentration. The plants could be exposed to parasites. The students of Ronneby also see possibilities due to climate change. There might be more tourists as the temperature increases. It could mean faster development for renewable energy sources. It could be possible to grow exotic fruits and vegetables in Ronneby if the temperature increases. Written by Mr. Anders Thomsson, teacher of Geography and Biology.

Inelastic processes in atomic collisions involving ground state and laser-prepared atoms

NASA Astrophysics Data System (ADS)

Planje, Willem Gilles

1999-11-01

In dit proefschrift worden experimenten beschreven waarbij ionen of atomen met een bepaalde snelheid op een ensemble van doelwitatomen worden gericht. Wanneer twee deeltjes elkaar voldoende genaderd hebben, vindt er wissel- werking plaats waarbij allerlei processen kunnen optreden. Deze processen resulteren in specieke eindproducten. Kennis over de interactie tussen twee botsingspartners wordt verkregen door te bekijken welke eindproducten ontstaan, en in welke mate. Een belangrijke grootheid die van invloed is op mogelijke processen is de onderlinge snelheid van de twee kernen, oftewel de botsingssnelheid. Wanneer de botsingssnelheid voldoende klein is dan kunnen de verschillende reactiemechanismen zowel kwalitatief als kwanti- tatief vaak goed voorspeld worden door het systeem te beschouwen als een kort-stondig molecuul, opgebouwd uit de twee botsende deeltjes. De ver- schillende processen die kunnen optreden worden gekwaliceerd afhankelijk van de vorming van bepaalde eindproducten. Ruwweg de volgende indeling kan gemaakt worden: 1. de interne structuur van de eindproducten zijn identiek aan die van de beginproducten. We spreken dan van een elastische botsing. 2. e en van de deeltjes of beiden worden in een aangeslagen toestand ge- bracht (of ge¨oniseerd). Dit zijn processen waarbij de herschikte elek- tronen zich bij de oorspronkelijke kern bevinden. We spreken dan van excitatie of ionisatie. 3. e en of meerdere elektronen bevinden zich bij de andere kern na de botsing (eventueel in aangeslagen toestand). We spreken dan van elek- tronenoverdracht. In het eerste deel van deze dissertatie worden botsingsexperimenten tussen heliumionen en natriumatomen beschreven waarbij het proces van elek- tronenoverdracht wordt onderzocht. Bij dit mechanisme is het buitenste 117?Samenvatting natriumelektron betrokken. Deze kan relatief gemakkelijk `overspringen' naar het heliumion wanneer deze zich dicht in de buurt van het natrium- atoom bevindt. Het elektron kan hierbij een bepaalde (aangeslagen) toe- stand bezetten. Wij meten de bezetting van de heliumtoestanden die onder uitzending van XUV licht ( ? 58 nm) vervallen naar de heliumgrondtoe- stand. Door de lichtintensiteit te meten onderzoeken we de mate van elek- tronenoverdracht naar een selecte groep van singlet helium`eind'toestanden, namelijk He(1s2p), He(1s3s), He(1s3p) en He(1s3d). In een reactie- vergelijking ziet het mechanisme er als volgt uit: He + (1s) + ( Na(3s) Na(3p) e- -! He + Na + -! He(1s 2 ) +h(58 nm) + Na + Het experiment kent een extra dimensie door het feit dat het, in beginsel bol- symmetrische, natriumatoom een bepaalde ruimtelijk uitlijning kan worden meegegeven. Met behulp van laserlicht van een specieke frequentie en po- larisatie, wordt het buitenste natriumelektron in een aangeslagen p toestand gebracht. Het aanslaan naar deze toestand heeft als gevolg dat het valentie- elektron zich op grotere afstand van zijn kern bevindt dan voorheen. Daar- naast kan, afhankelijk van de gebruikte laserpolarisatie, het buitenste elek- tron zich nu rond de natriumkern bewegen volgens een bepaalde anisotrope verdeling, de bolsymmetrie is doorbroken. De eecten van de excitatie en ruimtelijk verdeling van dit natriumelektron op het proces van elektronen- overdracht zijn onderzocht voor botsingsenergie¨en vari¨erend van 0.5 keV tot 6.0 keV. De metingen laten zien dat het eect van laserexcitatie een bezettingstoe- name van de beschouwde singlet heliumtoestanden betekent, ongeacht de uitlijning van het natrium 3p elektron. Dit is simpelweg te begrijpen uit het feit dat het 3p natrium elektron minder sterk gebonden is en elektro- nenoverdracht makkelijker gaat. Daarnaast is de uitlijning van het aanges- lagen elektron van invloed op de elektronenoverdracht. De resultaten zijn vergeleken met berekeningen van S.E. Nielsen en T.H. Rod [13], die de elek- tronoverdracht beschrijven in een model waarbij het betrokken elektron zich beweegt in bepaalde eectieve potentiaalvelden. De goede overeenkomsten van onze metingen met de berekeningen rechtvaardigen de theoretische be- nadering van Nielsen en Rod. 118?Samenvatting In het tweede gedeelte van het proefschrift worden botsingen beschouwd tussen helium- en neonatomen. Hierbij wordt nu niet gekeken naar bots- ingsproducten die zich manifesteren door bepaald licht uit te zenden, maar een elektron emitteren met een bepaalde energie. Verschillende soorten `eind'producten kunnen elektronen uitzenden, waaronder de negatieve ion- toestanden. Het elektronenspectrum, gemeten voor dit botsingssysteem, vertoont twee pieken die het spectrum domineren bij 16.2 eV en 19.4 eV voor verschillende botsingsenergie¨en tussen de 0.35 keV en 6.0 keV. Deze piekstructuren wijzen op de vorming van de kort-levende, negatieve iontoe- standen Ne-(2p 5 3s 2 ) en He-(1s2s 2 ) ten gevolge van de overdracht van e en elektron: He 0 + Ne 0 -! He-(1s2s 2 ) +Ne + (2p 5 ) 3 10- 14 s -! He 0 (1s 2 ) +Ne + + e- (19.37 eV) He 0 + Ne 0 -! He + (1s) +Ne-(2p 5 3s 2 ) 2:5 10- 13 s -! He + (1s) +Ne 0 (2p 6 ) +e- (16.15 eV) De meetresultaten vertonen een fenomeen waarbij de bezettingen van de negatieve iontoestanden een oscillerend gedrag vertonen als functie van de botsingssnelheid. Dit duidt op interferentie tussen de twee bijna-ontaarde moleculaire toestanden [He- + Ne + ] en[He + + Ne-]. Het is echter zeer op- merkelijk dat deze oscillatie wordt waargenomen in een experiment als deze, waarin de uitgezonden elektronen worden gemeten ongeacht de afbuighoek van het heliumatoom. Dit impliceert een speciek aanslagmechanisme van de moleculaire negatieve iontoestanden. Nader beschouwing van het bots- ingssysteem laat zien dat het instantane molecuul twee overgangen moet ondergaan voordat de negatieve iontoestanden gevormd worden. Als gevolg hiervan is de snelheid waarmee het negatieve en positieve ion uit elkaar be- wegen nagenoeg onafhankelijk van de afbuighoek van het helium projectiel en is oscillatie mogelijk waarneembaar. De wisselwerking tussen de twee beschouwde moleculaire toestanden impliceert gecorreleerde overdracht van twee elektronen: He- + Ne + 2e- ! He + + Ne- Door het quasi-resonante systeem als resonant te beschouwen kan het fenomeen kwalitatief goed verklaard worden. 119?Samenvatting Inhet laatstedeelwordt de bevolkingvanauto¨oniserende natriumtoestanden bekeken in He +=0 + Na botsingen. In tegenstelling tot de voorgaande exper- imenten waarin elektronenoverdracht beschouwd werd, betreft het hier een excitatiemechanisme. De beschouwde `eind'producten, i.e. de auto¨oniserende natriumtoestanden, bestaan in het algemeen kort en gaan over naar een stabiele iontoestand onder uitzending van een elektron met een toestands- karakteristieke kinetische energie. Door de elektronenspectra te meten bij verschillende botsingsenergie¨en, wordt de bezetting van de auto¨oniserende toestanden onderzocht. Ook hier wordt het eect van laserexcitatie en laser- polarisatie van het natriumatoom op de vorming van deze toestanden, en de mate waarin, bekeken. De metingen laten zien dat zowel in He + -Na als in He 0 -Na botsingen de invloed van de ruimtelijk uitlijning van het buitenste natriumelektron op de elektronenspectra nihil is. Dit impliceert dat het betrokken 3p elektron hoofdzakelijk een passieve rol speelt in de vorming van auto¨oniserende toe- standen: het blijft hoofdzakelijk de 3p toestand bezetten als een `toeschouwer' zonder een overgang te maken naar een andere toestand. Dit wordt boven- dien bevestigd door het feit dat wanneer een fractie natriumatomen aange- slagen wordt naar de p toestand dit een even grote reductie betekent van onder meer de populatie van de auto¨oniserende toestand Na(2p 5 3s 2 ). De verwachte grote toename van Na(2p 5 3p 2 ) toestanden, in geval van Na(3p) doelwitten, is niet waargenomen. 120?121?122

Assessing catchment connectivity using hysteretic loops

NASA Astrophysics Data System (ADS)

Davis, Jason; Masselink, Rens; Goni, Mikel; Gimenez, Rafael; Casali, Javier; Seeger, Manuel; Keesstra, Saskia

2017-04-01

Storm events mobilize large proportions of sediments in catchment systems. Therefore understanding catchment sediment dynamics throughout the continuity of storms and how initial catchment states act as controls on the transport of sediment to catchment outlets is important for effective catchment management. Sediment connectivity is a concept which can explain the origin, pathways and sinks of sediments within catchments (Baartman et al., 2013; Parsons et al., 2015; Masselink et al., 2016a,b; Mekonnen et al., 2016). However, sediment connectivity alone does not provide a practicable mechanism by which the catchment's initial state - and thus the location of entrained sediment in the sediment transport cascade - can be characterized. Studying the dynamic relationship between water discharge (Q) and suspended sediment (SS) at the catchment outlet can provide a valuable research tool to infer the likely source areas and flow pathways contributing to sediment transport because the relationship can be characterized by predictable hysteresis patterns. Hysteresis is observed when the sediment concentration associated with a certain flow rate is different depending on the direction in which the analysis is performed - towards the increase or towards the diminution of the flow. However, the complexity of the phenomena and factors which determine the hysteresis make its interpretation ambiguous. Previous work has described various types of hysteretic loops as well as the cause for the shape of the loop, mainly pointing to the origin of the sediments. The data set for this study comes from four experimental watersheds in Navarre (Spain), owned and maintained by the Government of Navarre. These experimental watersheds have been monitored and studied since 1996 (La Tejería and Latxaga) and 2001 (Oskotz principal and Oskotz woodland). La Tejería and Latxaga watersheds are similar to each other regarding size (approximately 200 ha), geology (marls and sandstones), soils (fine texture topsoil), climate (humid sub Mediterranean) and land use (80-90% cultivated with winter grain crops). Ozkotz principal (ca.1,700 ha) is covered with forest and pasture (cattle-breeding); while Oskotz woodland (ca. 500 ha), a sub-watershed of the Oskotz principal, is almost completely covered with forest. The predominant climate in the Oskotz catchments sub-Atlantic. Furthermore, antecedent conditions and event characteristics were analysed. The loops were compared quantitatively and qualitatively between catchments for similar events and within the catchments for events with different characteristics. In this study, several measures to objectively classify hysteresis loops in an automated way were developed. These were consecutively used to classify several hundreds of loops from several agricultural catchments in Northern Spain. These loop characteristics were compared to event specific characteristics such as antecedent precipitation, time of year, and precipitation intensity, duration and total. The combination of hysteresis loops and variables influencing connectivity can then tell something about the sources of sediments for different events and catchments. References Baartman, J.E.M., Masselink, R.H., Keesstra, S.D., Temme, A.J.A.M., 2013. Linking landscape morphological complexity and sediment connectivity. Earth Surface Processes and Landforms 38: 1457-1471. Masselink RJH, Heckmann T, Temme AJAM, Anders NS, Gooren HPA, Keesstra SD. 2016. A network theory approach for a better understanding of overland flow connectivity. Hydrological Processes. DOI: 10.1002/hyp.10993 Masselink, R.J.H., Keesstra, S.D., Temme, A.J.A.M., Seeger, M., Giménez, R., Casalí, J., 2016. Modelling Discharge and Sediment Yield at Catchment Scale Using Connectivity Components. Land Degradation and Development 27: 933-945, DOI: 10.1002/ldr.2512 Mekonnen, M., Keesstra, S.D., Baartman, J.E.M., Stroosnijder, L., Maroulis, J., Reducing sediment connectivity through man-made and natural sediment sinks in the Minizr catchment, north-west Ethiopia. Accepted to Land Degradation and Development. Parsons A.J., Bracken L., Peoppl , R., Wainwright J., Keesstra, S.D., 2015. Editorial: Introduction to special issue on connectivity in water and sediment dynamics. In press in Earth Surface Processes and Landforms. DOI: 10.1002/esp.3714

PREFACE: The IARU International Scientific Congress on Climate Change: Global Risks, Challenges and Decisions (10-12 March, Copenhagen, Denmark)

NASA Astrophysics Data System (ADS)

2009-01-01

In an attempt to make the main results from the Congress on Climate Change: Global Risk, Challenges and Decisions available to the public as early as possible, the steering committee decided to publish all talks and posters presented at the Congress in this unique collection of abstracts, in time for the conference Further to the abstract collection the Congress will publish two more products in the near future as described in the following; a synthesis report with the main conclusions, and a book aimed at an academic audience 1 Two Products from the Congress Two products are being produced based on the presentations and discussions at the Congress The first product will be a synthesis report of the main conclusions from the Congress The synthesis report will be ready in June 2009 The synthesis has the purpose of explaining the current state of understanding man-made climate change and what we can do about it to the non-scientist, ie politicians, media and interested citizens The synthesis will build on the messages presented to the Danish Prime Minister, Mr Anders Fogh Rasmussen, host of the COP15, at the closing session of the Congress These six messages were drafted by the Writing Team (see below) based on input from the session chairs and a reading of the 1600+ abstracts submitted to the Congress The second product is a book aimed at an academic audience The book will include more detailed scientific results from all of the sessions and will be published by Cambridge University Press in 2010 It will be an extension and elaboration of the synthesis report Who's writing the Synthesis Report and the Book? A Writing Team consisting of 12 internationally respected scientists from all continents is responsible for developing both products When the synthesis report has been drafted by the Writing Team, it will be discussed in the Scientific Steering Committee of the Congress and reviewed by the Earth System Science Partnership (ESSP) and a group of experts identified by the IARU universities In keeping with normal scientific practice, a procedure for producing the synthesis report that has been adopted optimises the chances of arriving at a product that will receive a broad backing from the scientific community as being a message that can be sent to the non-scientific community and that explains current understanding in climate change science The Writing Team will also be responsible for writing the book Members of the Writing Team (in alphabetical order) Professor Joe Alcamo, University of Stellenbosch Dr Terry Barker, Cambridge University Professor Daniel Kammen, University of California - Berkeley Professor Rik Leemans, Environmental Systems Analysis Group, Wageningen University Professor Diana Liverman, Oxford University Professor Mohan Munasinghe, Chairman, Munasinghe Institute for Development (MIND) Dr Balgis Osman-Elasha, Higher Council for Environment and Natural Resources (HCENR), Sudan Professor Katherine Richardson, University of Copenhagen Professor John Schellnhuber, Potsdam Institute for Climate Impact Research and visiting professor at the University of Oxford Professor Will Steffen, Australian National University Professor Lord Nicholas Stern, London School of Economics and Political Science (LSE) Professor Ole Wæver, University of Copenhagen 2 Key Messages from the Congress Key Message 1: Climatic Trends Recent observations confirm that, given high rates of observed emissions, the worst-case IPCC scenario trajectories (or even worse) are being realized For many key parameters, the climate system is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts Key Message 2: Social disruption The research community is providing much more information to support discussions on 'dangerous climate change' Recent observations show that societies are highly vulnerable to even modest levels of climate change, with poor nations and communities particularly at risk Temperature rises above 2°C will be very difficult for contemporary societies to cope with, and will increase the level of climate disruption through the rest of the century Key Message 3: Long-Term Strategy Rapid, sustained, and effective mitigation based on coordinated global and regional action is required to avoid 'dangerous climate change' regardless of how it is defined Weaker targets for 2020 increase the risk of crossing tipping points and make the task of meeting 2050 targets more difficult Delay in initiating effective mitigation actions increases significantly the long-term social and economic costs of both adaptation and mitigation Key Message 4: Equity Dimensions Climate change is having, and will have, strongly differential effects on people within and between countries and regions, on this generation and future generations, and on human societies and the natural world An effective, well-funded adaptation safety net is required for those people least capable of coping with climate change impacts, and a common but differentiated mitigation strategy is needed to protect the poor and most vulnerable Key Message 5: Inaction is Inexcusable There is no excuse for inaction We already have many tools and approaches - economic, technological, behavioral, management - to deal effectively with the climate change challenge But they must be vigorously and widely implemented to achieve the societal transformation required to decarbonize economies A wide range of benefits will flow from a concerted effort to alter our energy economy now, including sustainable energy job growth, reductions in the health and economic costs of climate change, and the restoration of ecosystems and revitalization of ecosystem services Key Message 6: Meeting the Challenge To achieve the societal transformation required to meet the climate change challenge, we must overcome a number of significant constraints and seize critical opportunities These include reducing inertia in social and economic systems; building on a growing public desire for governments to act on climate change; removing implicit and explicit subsidies; reducing the influence of vested interests that increase emissions and reduce resilience; enabling the shifts from ineffective governance and weak institutions to innovative leadership in government, the private sector and civil society; and engaging society in the transition to norms and practices that foster sustainability The editors of the volume are all the session chairs: Professor Agus Sari Dr Aled Jones Science Manager Anders Viksø-Nielsen Dr Andreas Barkman Professor Anette Reenberg Professor Ann Henderson-Sellers Professor Anthony J McMichael Dr Anthony Patt Dr Bette Otto-Bliesner Dr Cameron Hepburn Dr Carlos Nobre Dr Carol Turley Dr Chris Hope Professor Chris Turney Professor Claus Felby Professor Coleen Vogel Professor Dale Jamieson Professor Daniel M Kammen Senior Scientist Detlef F Sprinz Professor Diana Ürge-Vorsatz Professor Dorthe Dahl-Jensen PhD Fatima Denton Director Generel Frances Seymour Dr Frank Jotzo Professor Harold Mooney Director Henrik Bindslev Mr Jamie Pittock Professor Jacquie Burgess Dr James E Hansen Professor Jiahua Pan Dr Jill Jäger Professor Jim Skea Professor Johan Rockström Dr John Christensen Professor John Mitchell Professor John R Porter Professor Joyeeta Gupta Professor Jørgen E Olesen Professor Karen O'Brien Dr Kazuhiko Takeuchi Dr Katrine Krogh Andersen Professor Keith Paustian Professor Ken Caldeira Professor Kevin Anderson Dr Koko Warner Professor Konrad Steffen Professor Liping Zhou Professor Louise Fresco Professor Maria Carmen Lemos Professor Mark Ashton Dr Mark Stafford-Smith Dr Martin Claussen Dr Martin Visbeck Professor Mary Scholes Professor Masahide Kimoto Professor Matthew England Dr Maxwell Boykoff Dr Michael Raupach Professor Nathan Bindoff Professor Nicolas Gruber Professor Niels Elers Koch Professor Ole John Nielsen Professor Ole Wæver Professor Oran Young Dr Pamela Matson Dr Paul Baer Professor Paul Leadley Dr Pep Canadell Professor Pete Smith Professor Peter Gregory Professor Pier Vellinga Dr Rik Leemans Dr Roberto Bertollini Professor Roberto S Rodriguez Professor Scott Denning Dr Sivan Kartha Dr Thomas Downing Dr Tariq Banuri Professor Thomas Heyd Professor Tim Lenton Professor Timmons Roberts Professor Torkil Jønch Clausen Professor Warwick McKibbin Professor Wim C Turkenburg

EDITORIAL: 'Best article' prize for the 5th anniversary of Environmental Research Letters 'Best article' prize for the 5th anniversary of Environmental Research Letters

NASA Astrophysics Data System (ADS)

Kammen, Dan; Wright, Guillaume

2011-12-01

To celebrate the 5th anniversary of Environmental Research Letters (ERL) the publishers of the journal, IOP Publishing, have awarded a prize for the five best articles published in ERL since the journal began in 2006. The procedure for deciding the winning articles was as thorough as possible to ensure that the most outstanding articles would win the prize. A shortlist of 25 nominated research articles, five for each year since ERL was launched, which were chosen based on a range of criteria including novelty, scientific impact, readership, broad appeal and wider media coverage, was selected. The ERL Editorial Board then assessed and rated these 25 articles in order to choose a winning article for each year. We would like to announce that the following articles have been awarded ERL's 5th anniversary best article prize: 2006/7 The Bodélé depression: a single spot in the Sahara that provides most of the mineral dust to the Amazon forest Ilan Koren, Yoram J Kaufman, Richard Washington, Martin C Todd, Yinon Rudich, J Vanderlei Martins and Daniel Rosenfeld 2006 Environ. Res. Lett. 1 014005 2008 Causes and impacts of the 2005 Amazon drought Ning Zeng, Jin-Ho Yoon, Jose A Marengo, Ajit Subramaniam, Carlos A Nobre, Annarita Mariotti and J David Neelin 2008 Environ. Res. Lett. 3 014002 2009 How difficult is it to recover from dangerous levels of global warming? J A Lowe, C Huntingford, S C B Raper, C D Jones, S K Liddicoat and L K Gohar 2009 Environ. Res. Lett. 4 014012 2010 Is physical water scarcity a new phenomenon? Global assessment of water shortage over the last two millennia Matti Kummu, Philip J Ward, Hans de Moel and Olli Varis 2010 Environ. Res. Lett. 5 034006 2011 Implications of urban structure on carbon consumption in metropolitan areas Jukka Heinonen and Seppo Junnila 2011 Environ. Res. Lett. 6 014018 Our congratulations go to these authors. In recognition of their outstanding work, we are delighted to offer all of the authors of the winning articles free publication in the journal until the end of 2012. Of course all of the shortlisted papers were of great merit, and the full list of nominees can be found below (in alphabetical order). Nominees Achard F, DeFries R, Eva H, Hansen M, Mayaux P and Stibig H-J 2007 Environ. Res. Lett. 2 045022 Baccini A, Laporte N, Goetz S J, Sun M and Dong H 2008 Environ. Res. Lett. 3 045011 Barona E, Ramankutty N, Hyman G and Coomes O T 2010 Environ. Res. Lett. 5 024002 Charpentier A D, Bergerson J A and MacLean H L 2009 Environ. Res. Lett. 4 014005 Chester M V and Horvath A 2009 Environ. Res. Lett. 4 024008 Cooley S R and Doney S C 2009 Environ. Res. Lett. 4 024007 Diffenbaugh N S, White M A, Jones G V and Ashfaq M 2011 Environ. Res. Lett. 6 024024 Farrell A E and Brandt A R 2006 Environ. Res. Lett. 1 014004 Graham W M, Condon R H, Carmichael R H, D'Ambra I, Patterson H K, Linn L J and Hernandez F J Jr 2010 Environ. Res. Lett. 5 045301 Hansen J E 2007 Environ. Res. Lett. 2 024002 Heinonen J and Junnila S 2011 Environ. Res. Lett. 6 014018 Jackson R B et al 2008 Environ. Res. Lett. 3 044006 Jiang M, Michael Griffin W, Hendrickson C, Jaramillo P, VanBriesen J and Venkatesh A 2011 Environ. Res. Lett. 6 034014 Koren I, Kaufman Y J, Washington R, Todd M C, Rudich Y, Martins J V and Rosenfeld D 2006 Environ. Res. Lett. 1 014005 Kummu M, Ward P J, de Moel H and Varis O 2010 Environ. Res. Lett. 5 034006 Lau W K M, Kim M-K, Kim K-M and Lee W-S 2010 Environ. Res. Lett. 5 025204 Lindeboom H J et al 2011 Environ. Res. Lett. 6 035101 Lowe J A, Huntingford C, Raper S C B, Jones C D, Liddicoat S K and Gohar L K 2009 Environ. Res. Lett. 4 014012 Möhler O, Benz S, Saathoff H, Schnaiter M, Wagner R, Schneider J, Walter S, Ebert V and Wagner S 2008 Environ. Res. Lett. 3 025007 Menon S, Akbari H, Mahanama S, Sednev I and Levinson R 2010 Environ. Res. Lett. 5 014005 Schneider A, Friedl M A and Potere D 2009 Environ. Res. Lett. 4 044003 Sloan T and Wolfendale A W 2008 Environ. Res. Lett. 3 024001 Tedesco M, Fettweis X, van den Broeke M R, van de Wal R S W, Smeets C J P P, van de Berg W J, Serreze M C and Box J E 2011 Environ. Res. Lett. 6 014005 Wang M, Wu M and Huo H 2007 Environ. Res. Lett. 2 024001 Zeng N, Yoon J H, Marengo J A, Subramaniam A, Nobre C A, Mariotti A and Neelin J D 2008 Environ. Res. Lett. 3 014002

The Mars Pathfinder Mission and Science Results

NASA Technical Reports Server (NTRS)

Golombek, M. P.

1999-01-01

Mars Pathfinder, the first low-cost, quick Discovery class mission to be completed, successfully landed on the surface of Mars on July 4, 1997, deployed and navigated a small rover, and collected data from 3 science instruments and 10 technology experiments. The mission operated on Mars for 3 months and returned 2.3 Gbits of new data, including over 16,500 lander and 550 rover images, 16 chemical analyses of rocks and soil, and 8.5 million individual temperature, pressure and wind measurements. The rover traversed 100 m clockwise around the lander, exploring about 200 square meters of the surface. The mission captured the imagination of the public, and garnered front page headlines during the first week. A total of about 566 million internet "hits" were registered during the first month of the mission, with 47 million "hits" on July 8th alone, making the Pathfinder landing by far the largest internet event in history at the time. Pathfinder was the first mission to deploy a rover on Mars. It carried a chemical analysis instrument, to characterize the rocks and soils in a landing area over hundreds of square meters on Mars, which provided a calibration point or "ground truth" for orbital remote sensing observations. The combination of spectral imaging of the landing area by the lander camera, chemical analyses aboard the rover, and close-up imaging of colors, textures and fabrics with the rover cameras offered the potential of identifying rocks (petrology and mineralogy). With this payload, a landing site in Ares Vallis was selected because it appeared acceptably safe and offered the prospect of analyzing a variety of rock types expected to be deposited by catastrophic floods, which enabled addressing first-order scientific questions such as differentiation of the crust, the development of weathering products, and the nature of the early Martian environment and its subsequent evolution. The 3 instruments and rover allowed seven areas of scientific investigation: the geology and geomorphology of the surface, mineralogy and geochemistry of rocks and soils, physical properties of surface materials, magnetic properties of airborne dust, atmospheric science including aerosols, and rotational and orbital dynamics of Mars. Scientists were assembled into 7 Science Operations Groups that were responsible for requesting measurements by the 3 instruments, rover and engineering subsystems for carrying out their scientific investigations and for analyzing the data and reporting on their findings. The spacecraft was launched on December 4, 1996 and had a 7 month cruise to Mars, with four trajectory correction maneuvers. The vehicle entered the atmosphere directly following cruise stage separation. Parachute deployment, heatshield and lander separation, radar ground acquisition, airbag inflation and rocket ignition all occurred before landing at 2:58 AM true local solar time (9:56:55 AM PDT). The lander bounced at least 15 times up to 12 in high without airbag rupture, demonstrating the robustness of this landing system. Reconstruction of the final landing sequence indicates that the parachute/backshel1/1ander was tilted due to a northwest directed wind and wind shear, which resulted in the lander bouncing about I km to the northwest and initially downhill about 20 m from where the solid rockets fired. Two anomalously bright spots located in the lander scene are likely the heatshield, which continued in a ballistic trajectory about 2 km downrange (west southwest), and the backshell/parachute, which stayed nearer to where the rockets fired. Unconnected disturbed soil patches in the scene indicate that the final few bounces of the lander were from the east-southeast and were followed by a gentle roll to the west before coming to rest on the base petal. The location of the lander away from where the solid rockets fired and considerations of the exhaust products used to inflate the airbags and their fate, indicate that the Pathfinder landing system is one of the cleanest designed leaving the local area essentially contaminant free. The radio signal from the low-=gain antenna was received at 11:34 AM PDT indicating a successful landing.

EDITORIAL: Focus on Quantum Dissipation in Unconventional Environments FOCUS ON QUANTUM DISSIPATION IN UNCONVENTIONAL ENVIRONMENTS

NASA Astrophysics Data System (ADS)

Grifoni, Milena; Paladino, Elisabetta

2008-11-01

Quantum dissipation has been the object of study within the physics and chemistry communities for many years. Despite this, the field is in constant evolution, largely due to the fact that novel systems where the understanding of dissipation and dephasing processes is of crucial importance have become experimentally accessible in recent years. Among the ongoing research themes, we mention the defeat of decoherence in solid state-based quantum bits (qubits) (e.g. superconducting qubits or quantum dot based qubits), or dissipation due to non-equilibrium Fermi reservoirs, as is the case for quantum transport through meso- and nanoscale structures. A close inspection of dissipation in such systems reveals that one has to deal with 'unconventional' environments, where common assumptions of, for example, linearity of the bath and/or equilibrium reservoir have to be abandoned. Even for linear baths at equilibrium it might occur that the bath presents some internal structure, due, for example, to the presence of localized bath modes. A large part of this focus issue is devoted to topics related to the rapidly developing fields of quantum computation and information with solid state nanodevices. In these implementations, single and two-qubit gates as well as quantum information transmission takes place in the presence of broadband noise that is typically non-Markovian and nonlinear. On both the experimental and theory side, understanding and defeating such noise sources has become a crucial step towards the implementation of efficient nanodevices. On a more fundamental level, electron and spin transport through quantum dot nanostructures may suffer from 'unconventional' dissipation mechanisms such as the simultaneous presence of spin relaxation and fermionic dissipation, or may represent themselves out of equilibrium baths for nearby mesoscopic systems. Finally, although not expected from the outset, the present collection of articles has revealed that different 'unconventional' questions were still open on the standard harmonic oscillator and spin baths. This includes both fundamental issues, such as the possibility of estimating the specific heat for a free particle in the presence of dissipation, and the development of methods suitable to dealing with long range correlations at zero temperature and with quantum chaotic environments. We believe that the present focus issue on Quantum Dissipation in Unconventional Environments, although certainly not exhaustive, provides an important open-access resource that presents the latest state of the art of research in this field along its different lines. Focus on Quantum Dissipation in Unconventional Environments Contents Dephasing by electron-electron interactions in a ballistic Mach-Zehnder interferometer Clemens Neuenhahn and Florian Marquardt Quantum frustration of dissipation by a spin bath D D Bhaktavatsala Rao, Heiner Kohler and Fernando Sols A random matrix theory of decoherence T Gorin, C Pineda, H Kohler and T H Seligman Dissipative dynamics of a biased qubit coupled to a harmonic oscillator: analytical results beyond the rotating wave approximation Johannes Hausinger and Milena Grifoni Dissipative dynamics of a two-level system resonantly coupled to a harmonic mode Frederico Brito and Amir O Caldeira Spin correlations in spin blockade Rafael Sánchez, Sigmund Kohler and Gloria Platero Landau-Zener tunnelling in dissipative circuit QED David Zueco, Peter Hänggi and Sigmund Kohler Quantum oscillations in the spin-boson model: reduced visibility from non-Markovian effects and initial entanglement F K Wilhelm Dynamics of dissipative coupled spins: decoherence, relaxation and effects of a spin-boson bath P Nägele, G Campagnano and U Weiss Spin chain model for correlated quantum channels Davide Rossini, Vittorio Giovannetti and Simone Montangero Finite quantum dissipation: the challenge of obtaining specific heat Peter Hänggi, Gert-Ludwig Ingold and Peter Talkner Dynamics of large anisotropic spin in a sub-ohmic dissipative environment close to a quantum-phase transition Frithjof B Anders Effects of low-frequency noise cross-correlations in coupled superconducting qubits A D'Arrigo, A Mastellone, E Paladino and G Falci From coherent motion to localization: dynamics of the spin-boson model at zero temperature Haobin Wang and Michael Thoss Phonon distributions of a single-bath mode coupled to a quantum dot F Cavaliere, G Piovano, E Paladino and M Sassetti

A new approach to the study of therapeutic work in the transference.

PubMed

Pessier, J; Stuart, J

2000-02-01

This article proposes a new method for evaluating the effects of therapist and patient work in the transference. Work in the transference is often difficult for the patient, and may show a characteristic pattern of lag between a transference interpretation and its therapeutic effect. To account for this lag, we assessed patient responses to interpretations over the course of entire sessions. The narratives patients told about others, or Relationship Episodes (REs), were used as units of study. In a sample of three consecutive sessions taken from each of three psychodynamic cases, we identified several instances when transference work appeared to have an initial inhibitory effect, but facilitated progress over the course of the entire session. We recommend that to examine the effects of interpretations future studies use longer, more clinically meaningful segments of patient speech than have been used in the past. Dieser Beitrag propagiert eine neue Methode zur Evaluierung der Effekte von Übertragungsarbeit durch Therapeut und Patient. Arbeit in der Übertragung ist für den Patienten oftmals schwierig und zeigt häufig eine charakteristisches Muster von zeitlichen Verzögerungen bzgl. Übertragungsdeutungen und deren therapeutischen Effekten. Um diese zeitliche Verzögerung zu erklären, untersuchten wir die Reaktionen von Patienten auf derartige Deutungen im Verlauf ganzer Sitzungen. Narrative, in denen die Patienten über andere berichteten, also Beziehungsepisoden, dienten in dieser Studie als Einheit. In einter Stichprobe dreier aufeinanderfolgender Sitzugnen, die sich auf drei Fälle bezogen, identifizierten wir verschiedene Umstände, unter denen Übertragungsarbeit anfänglich einen hemmenden Affekt zu haben schien, letztlich aber den Gesamtverlauf der Sitzung günstig beeinflussten. Wir empfehlen, in Zukunft die Effekte von Übertragungsdeutungen auf der Basis längerer, klinische sinnvoller Segmente von Patientenäußerungen zu untersuchen als dies in der Vergangenheit der Fall war. Cet article propose une nouvelle méthode pour évaluer les effets du travail sur le transfert entre thérapeute et patient. Ce travail est souvent difficile pour le patient, et il peut y avoir un pattern caractéristique de délai entre une înterprétation de transfert et son effet thérapeutique. Pour expliquer ce délai, nous avons évalué les réponses des patients à des interprétatios au cours de séances entières. C'est les narrations des patients sur d'autres, ou Episodes Relationnels (ERs), qui ont constitué les unités de base de cette étude. Dans un échantillon de 3 séances consécutives venant de 3 cas psychodynamiques, nous avons identifié plusieurs moments où le traail sur le transfert semblait avoir un effet inhibitoire initial, mais favorisait le progrès en regardant la séance entière. Nous recommandons pour de futures études sur l'effet des interprétations de prendre des segments plus longs et cliniquement significatifs du récit du patient que ceux utilisés dans le passé. Este artículo propone un nuevo método para evaluar los efectos del trabajo de terapeuta y paciente en la transferencia. El trabajo en la transferencia es, con frecuencia, dificil para el paciente y puede mostrar un lapso característico entre una interpretación transferencial y sus efectos terapéuticos. Para explicar este lapso, hemos evaluado las respuestas del paciente a las interpretaciones a lo largo de sesiones enteras. Como unidad de estudio se usaron las narrativas de los pacientes acerca de otros, o sea, los episodios relacionales (REs). En una muestra de tres sesiones consecutivas tomadas de tres casos psicodinámicos, identificamos varioss casos en los que la trasferencia parecía tener un efecto inicial inhibitorio, aunque se vio que a lo largo de la sesión facilitaba el progreso. Recomendamos que, para examinar los efectos de las interpretaciones, los futuros estudios usen segmentos más largos y clínicamente más significativos del habia del paciente que los que se usaron en el pasado.

EDITORIAL: Focus on Cloaking and Transformation Optics

NASA Astrophysics Data System (ADS)

Leonhardt, Ulf; Smith, David R.

2008-11-01

'Any sufficiently advanced technology is indistinguishable from magic', as the late Arthur C Clarke wrote. So what does it take to do magic by technology? Transformation optics has developed some tantalizing ideas and the first practical demonstrations of 'pure and applied magic'. Transformation optics gathers an unusual mix of scientists, ranging from practically-minded engineers to imaginative theoretical physicists and mathematicians or hybrids of all three. The engineers have been developing new materials with extraordinary electromagnetic properties, from materials for microwaves, to be used in radar or wireless technology, to materials for terahertz radiation and visible light. These materials typically are composites—they consist of artificial structures much smaller than the wavelength that act like man-made atoms, apart being much larger in size. The properties of these artificial atoms depend on their shapes and sizes and so they are tunable, in contrast to most real atoms or molecules. This degree of control is what makes these materials—called metamaterials—so interesting. Such new-won freedom invites the other side of the spectrum of scientists, the theorists, to dream. Just imagine there are no practical limits on electromagnetic materials—what could we do with them? One exciting application of metamaterials has been Veselago's idea of negative refraction, dating back to the 1960s. Metamaterials have breathed life into Veselago's idea, culminating in recent optical demonstrations (see for example [1,2]). Another application is cloaking, developing ideas and first experimental demonstrations for invisibility devices [3]. It turns out that both negative refraction and cloaking are examples where materials seem to transform the geometry of space. Any optical material appears to change light's perception of space, as countless optical illusions prove, but the materials of transformation optics act in more specific ways: they appear to perform coordinate transformations. If the coordinates they conjure up run backwards one gets negative refraction, if they exclude some region of space one makes anything inside invisible [4]. In physics, general relativity has honed the theoretical tools for understanding curved space and curved-coordinate transformations. In transformation optics, general relativity has become a theoretical tool for solving practical engineering problems [4]. What an unorthodox connection! This focus issue represents a snapshot of this rapidly developing research area. It is not restricted to optics or electromagnetism, though. Metamaterials for acoustics also exist and can be applied in ways similar to optical metamaterials. So transformation optics not only attracts an unusual mix of scientists, but also spans a range of applications in optics and beyond. Transformation optics has the potential to transform optics, for example by visualizing invisibility and making materials beyond materials—metamaterials. But before we transgress the boundaries to the hermeneutics of transformation optics [5], let the papers speak for themselves. References [1] Yao J, Liu Z, Liu Y, Wang Y, Sun C, Bartal G, Stacy A M and Zhang X 2008 Science 321 930 [2] Valentine J, Zhang S, Zentgraf T, Ulin-Avila E, Genov D A, Bartal G and Zhang X 2008 Nature 455 376 [3] Schurig D, Mock J J, Justice B J, Cummer S A, Pendry J B, Starr A F and Smith D R 2006 Science 314 977 [4] Leonhardt U and Philbin T G 2006 New J. Phys. 8 247 [5] Sokal A D 1996 Social Text 14(46/47) 217 Focus on Cloaking and Transformation Optics Contents Transformation optics for the full dielectric electromagnetic cloak and metal-dielectric planar hyperlens D P Gaillot, C Croënne, F Zhang and D Lippens Transmutation of singularities in optical instruments Tomáš Tyc and Ulf Leonhardt Electromagnetic cloaking with canonical spiral inclusions K Guven, E Saenz, R Gonzalo, E Ozbay and S Tretyakov Theory and potentials of multi-layered plasmonic covers for multi-frequency cloaking Andrea Alù and Nader Engheta Electromagnetic cloaking devices for TE and TM polarizations Filiberto Bilotti, Simone Tricarico and Lucio Vegni An aberration-free lens with zero F-number D Schurig Transformational optics of plasmonic metamaterials I I Smolyaninov An acoustic metafluid: realizing a broadband acoustic cloak J B Pendry and Jensen Li On the possibility of metamaterial properties in spin plasmas G Brodin and M Marklund A homogenization route towards square cylindrical acoustic cloaks Mohamed Farhat, Sébastien Guenneau, Stefan Enoch, Alexander Movchan, Frédéric Zolla and André Nicolet Transformation optics: approaching broadband electromagnetic cloaking A V Kildishev, W Cai, U K Chettiar and V M Shalaev Generalized field-transforming metamaterials Sergei A Tretyakov, Igor S Nefedov and Pekka Alitalo Electromagnetic beam modulation through transformation optical structures Xiaofei Xu, Yijun Feng and Tian Jiang Superantenna made of transformation media Ulf Leonhardt and Tomáš Tyc Material parameters and vector scaling in transformation acoustics Steven A Cummer, Marco Rahm and David Schurig Isotropic transformation optics: approximate acoustic and quantum cloaking Allan Greenleaf, Yaroslav Kurylev, Matti Lassas and Gunther Uhlmann Transformation optical designs for wave collimators, flat lenses and right-angle bends Do-Hoon Kwon and Douglas H Werner Alternative derivation of electromagnetic cloaks and concentrators A D Yaghjian and S Maci Solutions in folded geometries, and associated cloaking due to anomalous resonance Graeme W Milton, Nicolae-Alexandru P Nicorovici, Ross C McPhedran, Kirill Cherednichenko and Zubin Jacob Finite wavelength cloaking by plasmonic resonance N-A P Nicorovici, R C McPhedran, S Enoch and G Tayeb

EDITORIAL: Focus on Quantum Information and Many-Body Theory

NASA Astrophysics Data System (ADS)

Eisert, Jens; Plenio, Martin B.

2010-02-01

Quantum many-body models describing natural systems or materials and physical systems assembled piece by piece in the laboratory for the purpose of realizing quantum information processing share an important feature: intricate correlations that originate from the coherent interaction between a large number of constituents. In recent years it has become manifest that the cross-fertilization between research devoted to quantum information science and to quantum many-body physics leads to new ideas, methods, tools, and insights in both fields. Issues of criticality, quantum phase transitions, quantum order and magnetism that play a role in one field find relations to the classical simulation of quantum systems, to error correction and fault tolerance thresholds, to channel capacities and to topological quantum computation, to name but a few. The structural similarities of typical problems in both fields and the potential for pooling of ideas then become manifest. Notably, methods and ideas from quantum information have provided fresh approaches to long-standing problems in strongly correlated systems in the condensed matter context, including both numerical methods and conceptual insights. Focus on quantum information and many-body theory Contents TENSOR NETWORKS Homogeneous multiscale entanglement renormalization ansatz tensor networks for quantum critical systems M Rizzi, S Montangero, P Silvi, V Giovannetti and Rosario Fazio Concatenated tensor network states R Hübener, V Nebendahl and W Dür Entanglement renormalization in free bosonic systems: real-space versus momentum-space renormalization group transforms G Evenbly and G Vidal Finite-size geometric entanglement from tensor network algorithms Qian-Qian Shi, Román Orús, John Ove Fjærestad and Huan-Qiang Zhou Characterizing symmetries in a projected entangled pair state D Pérez-García, M Sanz, C E González-Guillén, M M Wolf and J I Cirac Matrix product operator representations B Pirvu, V Murg, J I Cirac and F Verstraete SIMULATION AND DYNAMICS A quantum differentiation of k-SAT instances B Tamir and G Ortiz Classical Ising model test for quantum circuits Joseph Geraci and Daniel A Lidar Exact matrix product solutions in the Heisenberg picture of an open quantum spin chain S R Clark, J Prior, M J Hartmann, D Jaksch and M B Plenio Exact solution of Markovian master equations for quadratic Fermi systems: thermal baths, open XY spin chains and non-equilibrium phase transition Tomaž Prosen and Bojan Žunkovič Quantum kinetic Ising models R Augusiak, F M Cucchietti, F Haake and M Lewenstein ENTANGLEMENT AND SPECTRAL PROPERTIES Ground states of unfrustrated spin Hamiltonians satisfy an area law Niel de Beaudrap, Tobias J Osborne and Jens Eisert Correlation density matrices for one-dimensional quantum chains based on the density matrix renormalization group W Münder, A Weichselbaum, A Holzner, Jan von Delft and C L Henley The invariant-comb approach and its relation to the balancedness of multipartite entangled states Andreas Osterloh and Jens Siewert Entanglement scaling of fractional quantum Hall states through geometric deformations Andreas M Läuchli, Emil J Bergholtz and Masudul Haque Entanglement versus gap for one-dimensional spin systems Daniel Gottesman and M B Hastings Entanglement spectra of critical and near-critical systems in one dimension F Pollmann and J E Moore Macroscopic bound entanglement in thermal graph states D Cavalcanti, L Aolita, A Ferraro, A García-Saez and A Acín Entanglement at the quantum phase transition in a harmonic lattice Elisabeth Rieper, Janet Anders and Vlatko Vedral Multipartite entanglement and frustration P Facchi, G Florio, U Marzolino, G Parisi and S Pascazio Entropic uncertainty relations—a survey Stephanie Wehner and Andreas Winter Entanglement in a spin system with inverse square statistical interaction D Giuliano, A Sindona, G Falcone, F Plastina and L Amico APPLICATIONS Time-dependent currents of one-dimensional bosons in an optical lattice J Schachenmayer, G Pupillo and A J Daley Implementing quantum gates using the ferromagnetic spin-J XXZ chain with kink boundary conditions Tom Michoel, Jaideep Mulherkar and Bruno Nachtergaele Long-distance entanglement in many-body atomic and optical systems Salvatore M Giampaolo and Fabrizio Illuminati QUANTUM MEMORIES AND TOPOLOGICAL ORDER Thermodynamic stability criteria for a quantum memory based on stabilizer and subsystem codes Stefano Chesi, Daniel Loss, Sergey Bravyi and Barbara M Terhal Topological color codes and two-body quantum lattice Hamiltonians M Kargarian, H Bombin and M A Martin-Delgado RENORMALIZATION Local renormalization method for random systems O Gittsovich, R Hübener, E Rico and H J Briegel

LHC Nobel Symposium Proceedings

NASA Astrophysics Data System (ADS)

Ekelöf, Tord

2013-12-01

In the summer of 2012, a great discovery emerged at the Large Hadron Collider (LHC) at CERN in Geneva. A plethora of new precision data had already by then been collected by the ATLAS and CMS experiments at LHC, providing further extensive support for the validity of the Standard Model of particle physics. But what now appeared was the first evidence for what was not only the last unverified prediction of the Standard Model, but also perhaps the most decisive one: the prediction made already in 1964 of a unique scalar boson required by the theory of François Englert and Peter Higgs on how fundamental particles acquire mass. At that moment in 2012, it seemed particularly appropriate to start planning a gathering of world experts in particle physics to take stock of the situation and try to answer the challenging question: what next? By May 2013, when the LHC Nobel Symposium was held at the Krusenberg Mansion outside Uppsala in Sweden, the first signs of a great discovery had already turned into fully convincing experimental evidence for the existence of a scalar boson of mass about 125 GeV, having properties compatible with the 50-year-old prediction. And in October 2013, the evidence was deemed so convincing that the Swedish Royal Academy of Sciences awarded the Nobel Prize in Physics to Englert and Higgs for their pioneering work. At the same time the search at the LHC for other particles, beyond those predicted by the Standard Model, with heavier masses up to—and in some cases beyond—1 TeV, had provided no positive result. The triumph of the Standard Model seems resounding, in particular because the mass of the discovered scalar boson is such that, when identified with the Higgs boson, the Standard Model is able to provide predictions at energies as high as the Planck mass, although at the price of accepting that the vacuum would be metastable. However, even if there were some feelings of triumph, the ambience at the LHC Nobel Symposium was more one of puzzlement. The apparent absence of hints in the LHC experimental data of new phenomena that could relate to dark matter, dark energy, the dominance of matter over antimatter in the Universe, the unification of the strong and the electroweak interactions and their further unification with gravity left the Symposium with no guidance as to how to answer the question: what next? And in experimental fundamental science it is not the confirmation of already established theories that thrills the most; it is the appearance of the unexpected that creates the greatest excitement. However, the LHC is only at the beginning of its voyage into the uncharted territories of higher energies and smaller dimensions that it was built for, so the possibilities for unexpected discoveries are only starting to be explored. The LHC will start up again in 2015 with nearly twice its previous energy and with increased luminosity—new discoveries might then appear sooner than we even dare hope for! The LHC Nobel Symposium was attended by about 60 invited participants and lasted four days. The program was divided into seven sessions; QCD and Heavy Ion Physics, B Physics, Electroweak Physics, The Higgs Boson, Connections to Neutrino Physics and Astroparticle Physics, Beyond the Standard Model and Forward Look. There were 27 plenary invited talks given by participants, each followed by lively discussions. All but one of the speakers have submitted write-ups of their talks for these proceedings. We are hopeful that the remaining talk will be published in a forthcoming issue of Physica Scripta . I am gratified that Professor Roland Allen has agreed to write a paper on the essence of the Higgs boson discovery to be published in Physica Scripta , intended for undergraduate students and educated physicists, regardless of their field of research. I wish to express my deep gratitude to all Speakers and Participants in the Symposium, to the Members of the Local and International Organizing Committees, to the referees of these Proceedings and to the staff at Uppsala University, in particular my Administrative Assistant for the Symposium, Marja Fahlander, at the Royal Swedish Academy of Sciences, at the Nobel Foundation and at the Institute of Physics Publishing Company for Physica Scripta for realizing this enlightening Symposium at its proceedings. The Nobel Symposium was financed by the Nobel Foundation. Tord Ekelöf Chair of the LHC Nobel Symposium Local Organizing Committee and LHC Nobel Guest Editor for the Symposium Proceedings Members of the Local Organizing Committee of the LHC Nobel Symposium Tord Ekelöf (Uppsala University, Chair) Kerstin Jon-And (Stockholms University) Bengt Lund-Jensen (Royal Institute of Technology) Anders Oskarsson (Lunds University) Torsten Åkesson (Lund University) Barbro Åsman (Swedish Royal Academy of Sciences) Members of the International Advisory Committee of the LHC Nobel Symposium Pierluigi Campana (INFN Frascati) Fabiola Gianotti (CERN) Paolo Giubellino (INFN-Torino) Joe Incandela (UC Santa Barbara) Young-Kee Kim (FNAL) Michelangelo Mangano (CERN) Lisa Randall (Harvard University)

NASA Releases New High-Resolution Earthrise Image

NASA Image and Video Library

2017-12-08

NASA's Lunar Reconnaissance Orbiter (LRO) recently captured a unique view of Earth from the spacecraft's vantage point in orbit around the moon. "The image is simply stunning," said Noah Petro, Deputy Project Scientist for LRO at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The image of the Earth evokes the famous 'Blue Marble' image taken by Astronaut Harrison Schmitt during Apollo 17, 43 years ago, which also showed Africa prominently in the picture." In this composite image we see Earth appear to rise over the lunar horizon from the viewpoint of the spacecraft, with the center of the Earth just off the coast of Liberia (at 4.04 degrees North, 12.44 degrees West). The large tan area in the upper right is the Sahara Desert, and just beyond is Saudi Arabia. The Atlantic and Pacific coasts of South America are visible to the left. On the moon, we get a glimpse of the crater Compton, which is located just beyond the eastern limb of the moon, on the lunar farside. LRO was launched on June 18, 2009, and has collected a treasure trove of data with its seven powerful instruments, making an invaluable contribution to our knowledge about the moon. LRO experiences 12 earthrises every day; however the spacecraft is almost always busy imaging the lunar surface so only rarely does an opportunity arise such that its camera instrument can capture a view of Earth. Occasionally LRO points off into space to acquire observations of the extremely thin lunar atmosphere and perform instrument calibration measurements. During these movements sometimes Earth (and other planets) pass through the camera's field of view and dramatic images such as the one shown here are acquired. This image was composed from a series of images taken Oct. 12, when LRO was about 83 miles (134 kilometers) above the moon's farside crater Compton. Capturing an image of the Earth and moon with LRO's Lunar Reconnaissance Orbiter Camera (LROC) instrument is a complicated task. First the spacecraft must be rolled to the side (in this case 67 degrees), then the spacecraft slews with the direction of travel to maximize the width of the lunar horizon in LROC's Narrow Angle Camera image. All this takes place while LRO is traveling faster than 3,580 miles per hour (over 1,600 meters per second) relative to the lunar surface below the spacecraft! The high-resolution Narrow Angle Camera (NAC) on LRO takes black-and-white images, while the lower resolution Wide Angle Camera (WAC) takes color images, so you might wonder how we got a high-resolution picture of the Earth in color. Since the spacecraft, Earth, and moon are all in motion, we had to do some special processing to create an image that represents the view of the Earth and moon at one particular time. The final Earth image contains both WAC and NAC information. WAC provides the color, and the NAC provides high-resolution detail. "From the Earth, the daily moonrise and moonset are always inspiring moments," said Mark Robinson of Arizona State University in Tempe, principal investigator for LROC. "However, lunar astronauts will see something very different: viewed from the lunar surface, the Earth never rises or sets. Since the moon is tidally locked, Earth is always in the same spot above the horizon, varying only a small amount with the slight wobble of the moon. The Earth may not move across the 'sky', but the view is not static. Future astronauts will see the continents rotate in and out of view and the ever-changing pattern of clouds will always catch one's eye, at least on the nearside. The Earth is never visible from the farside; imagine a sky with no Earth or moon - what will farside explorers think with no Earth overhead?" NASA's first Earthrise image was taken with the Lunar Orbiter 1 spacecraft in 1966. Perhaps NASA's most iconic Earthrise photo was taken by the crew of the Apollo 8 mission as the spacecraft entered lunar orbit on Christmas Eve Dec. 24, 1968. That evening, the astronauts -- Commander Frank Borman, Command Module Pilot Jim Lovell, and Lunar Module Pilot William Anders -- held a live broadcast from lunar orbit, in which they showed pictures of the Earth and moon as seen from their spacecraft. Said Lovell, "The vast loneliness is awe-inspiring and it makes you realize just what you have back there on Earth." Credit: NASA/Goddard/Arizona State University NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Obituary: Frank Culver Jones, 1932-2007

NASA Astrophysics Data System (ADS)

Ormes, Johnathan F.; Streitmatter, Robert E.

2007-12-01

Frank C. Jones, an emeritus theoretical physicist at NASA, died May 2, 2007 at age 74 after a struggle with a rare form of cancer. He died at his home in Silver Spring, Maryland, surrounded by his family. Frank was born July 30, 1932 in Fort Worth, Texas, the oldest of three boys. His parents were Kenneth Hugh and Nancy Culver Jones. Frank's father was a lawyer, and his grandfather was a Methodist minister. Frank graduated from Rice University in 1954 and earned a master's degree in 1955 and a doctorate in 1961, both in physics, from the University of Chicago. He did his graduate work with Prof. John Simpson. Dr. Jones began his professional career as an instructor in physics at Princeton University before joining NASA's Goddard Space Flight Center in 1963 as a National Research Council associate. He subsequently became a member of the Theory Division and the Laboratory for High Energy Astrophysics. His area of expertise was the origin, transport, and electromagnetic interactions of cosmic rays. His particular focus was the stochastic physics related to the diffusion of particles in random fields, plasma turbulence, and the shock acceleration of charged particles in collisionless plasmas. From 1993 to 1995, Frank was head of Goddard's Theoretical High Energy Astrophysics Office and continued to serve as Head of the Theory group. In 2003 he served as Acting Chief of the Laboratory for High Energy Astrophysics. He retired in 2005 and continued his affiliation with NASA as an emeritus scientist at Goddard until his death. As a youngster, Frank showed the signs of curiosity and initiative that indicated he might become an experimentalist. At the memorial service for Frank, his brother related the stories of how Frank had rigged a hidden microphone to play through the family television as his brother courted a young woman on the front porch swing, and how one of Frank's early chemistry experiments caused all the family silverware to turn black. Although Frank started his professional career as an experimentalist, his wife Ardythe says he didn't become really happy until he turned to theoretical work after his postdoctoral appointment at Princeton. Frank, with characteristic good humor, was not averse to telling his experimentalist friends that, after attempting balloon-borne experiments, he decided he was better suited to theoretical work. In more than four decades of research at NASA, Dr. Jones made a number of pioneering contributions to his area of expertise, regularly attending and presenting his work at the biannual International Cosmic Ray Conferences sponsored by the International Union of Pure and Applied Physics (IUPAP). He was known among his colleagues for his low-key presentations that demonstrated his deep understanding of the fundamentals of broad areas of physics far removed from cosmic radiation. This knowledge, combined with his friendly, generous, and open personality, meant that he was much sought after for his insight, advice, and wisdom on physics generally. He authored a paper on Compton scattering--the decrease in energy of a high energy photon when it interacts with matter--that is still widely used (Jones, F. C. Physics Review. 167, p. 1159, 1968). His works on acceleration of particles at oblique shocks with M. Baring and D. Ellison (Advances in Space Research, 15, #8/9, p. 397, 1995 & Astrophysical Journal Supplement, 90, p. 547, 1994.) are essential references in the field. Frank's review paper with D. Ellison in Space Science Reviews is considered one of the classics in the field of particle acceleration (Space Science Reviews, 58, p. 259, 1992). Frank was never afraid to look at an unconventional idea. When scientists were searching for evidence of tachyons, Frank looked into the kind of Cherenkov radiation they might produce (Jones, F. C. Physics Review D, 6, p. 2727, 1972). Don Ellison, Professor at North Carolina State University and one of Frank's most productive graduate students, told us that Frank had an astonishing memory. Don said he used to visit with Frank after lunch to discuss progress on his dissertation and get advice. He would think that Frank was dozing off and not listening to his report. However, he would find that many weeks or even months later Frank would remember the conversation and quote it back to him long after he had forgotten the encounter. Frank's colleagues were also the beneficiaries of this recall ability in informal settings. An avid fan of vintage movies, Frank could recall a scene from movies released long ago to draw an analogy or encapsulate a pertinent idea for any point of discussion that happened to be on the table. Frank was elected a Fellow of the American Physical Society in 1974 and a Fellow of the American Association for the Advancement of Science in 1996, being cited for "theoretical investigations of propagation and acceleration of cosmic rays in the interstellar medium." Frank took his turn at public service duties. He was elected by his peers to a three-year term on the Executive Committee of the Cosmic Physics Division (now the Astrophysics Division) of the American Physical Society (APS) in 1980. He served the APS as Council Member from 1994 until 1997, as a member and chair of the Committee on Constitution and Bylaws 1996-1998, and as its Chair in 1997. Frank chaired the Publications Committee responsible for the volumes of the 19th International Cosmic Ray Conference in La Jolla, California, in 1985, as well as serving on the conference steering committee. In 1987, when COSNEWS, the Newsletter of the Cosmic Ray Commission of the IUPAP, needed a new Editor and Publisher, Frank volunteered and served until 2002. Frank loved computer technology and was highly regarded in the laboratory as a helpful expert on this new technology as it grew and personal computers came to be found in every office. These sometimes incomprehensible new devices were well understood by Frank. He was always providing helpful advice to everyone from technicians to scientists and managers. This generosity resulted in his becoming the first senior research scientist to be honored with the Laboratory's Peer Award. Survivors include his wife of 52 years, Ardythe Grube Jones of Silver Spring, Maryland, two children, Cheryl Mattis of Columbia and Timothy Jones of Silver Spring, two brothers, and four grandchildren.

Entwicklung von umwelt- und naturschutzgerechten Verfahren der landwirtschaftlichen Landnutzung für das Biosphärenreservat Schorfheide-Chorin

NASA Astrophysics Data System (ADS)

Meyer-Aurich, Andreas

1999-11-01

Mit der vorliegenden Arbeit werden exemplarisch Chancen und Grenzen der Integration von Umwelt- und Naturschutz in Verfahren der ackerbaulichen Landnutzung aufgezeigt. Die Umsetzung von Zielen des Umwelt- und Naturschutzes in Verfahren der Landnutzung ist mit verschiedenen Schwierigkeiten verbunden. Diese liegen zum einen in der Konkretisierung der Ziele, um diese umsetzen zu können, zum anderen in vielfach unzulänglichem Wissen über den Zusammenhang zwischen unterschiedlichen Formen der Landnutzung und insbesondere den biotischen Naturschutzzielen. Zunächst wird die Problematik der Zielfestlegung und Konkretisierung erörtert. Das Umweltqualitätszielkonzept von Fürst et al. (1992) stellt einen Versuch dar, Ziele des Umwelt- und Naturschutzes zu konkretisieren. Dieses Konzept haben Heidt et al. (1997) auf einen Landschaftsausschnitt von ca. 6000 ha im Biosphärenreservat Schorfheide-Chorin im Nordosten Brandenburgs angewendet. Eine Auswahl der von Heidt et al. (1997) formulierten Umweltqualitätsziele bildet die Basis dieser Arbeit. Für die ausgewählten Umweltqualitätsziele wurden wesentliche Einflussfaktoren der Landnutzung identifiziert und ein Bewertungssystem entwickelt, mit dem die Auswirkungen von landwirtschaftlichen Anbauverfahren auf diese Umweltqualitätsziele abgebildet werden können. Die praktizierte Landnutzung von 20 Betrieben im Biosphärenreservat Schorfheide-Chorin wurde von 1994 bis 1997 hinsichtlich ihrer Auswirkungen auf die Umweltqualitätsziele analysiert. Die Analyse ergab ein sehr differenziertes Bild, das zum Teil Unterschiede in der Auswirkung auf die Umweltqualitätsziele für den Anbau einzelner Kulturen oder für bestimmte Betriebstypen zeigte. Es zeigte sich aber auch, dass es bei der Gestaltung des Anbaus einzelner Kulturarten große Unterschiede gab, die für Umweltqualitätsziele Bedeutung haben. Neben der Analyse der Landnutzung im Biosphärenreservat Schorfheide-Chorin wurde ein System entwickelt, mit dem die modellhafte Abbildung von Verfahren der Landnutzung möglich ist. Die Modellverfahren wurden in eine umfangreiche Datenbank eingebunden. Sie wurden mit Hilfe eines Fuzzy- Regelsystems hinsichtlich ihrer Auswirkungen auf die Umweltqualitätsziele bewertet. Die systematisch bewerteten Verfahren wurden in ein Betriebsmodell integriert, womit eine weitergehende Analyse der Zielbeziehungen und die Berechnung von Szenarien mit unterschiedlichen Rahmenbedingungen ermöglicht wurde. Die Analyse der Beziehung verschiedener Ziele zueinander (Zieldivergenz, Zielkonvergenz) zeigte, dass sich mit der Verfolgung vieler Umweltqualitätsziele auch positive Effekte für andere Umweltqualitätsziele ergaben. Teilweise konnte allerdings auch eine Zieldivergenz festgestellt werden, die auf mögliche Zielkonflikte hinweist. Bei der Analyse der Szenarienergebnisse zeigte sich, dass die vorgeschlagenen Veränderungen von Rahmenbedingungen vielfach eine Verschlechterung für verschiedene Umweltqualitätsziele mit sich bringen. Eine Ursache dafür liegt darin, dass bei der Definition der Szenarien die Bedeutung der Stilllegungen unterschätzt wurde. The objective of this research was to show the opportunities and limitations associated with integrating of environmental goals into agricultural land use management. For this purpose, the impact of agricultural land uses on six environmental quality goals was analysed for an approximately 16.000 ha study region within the biosphere reserve Schorfheide-Chorin in north-eastern Brandenburg (Germany). The environmental quality goals considered were protection of ground water, preservation of groundwater recharge, protection of the soil against wind and water erosion and preservation of animal species typical of the agricultural landscape, in particular partridge, amphibians and cranes. For each environmental quality goal, an evaluation framework is presented which enables an assessment of the impact of agricultural land uses on the environmental quality goals. The evaluation framework was applied to assess the impact of land uses of twenty farms in the study area from 1994 to 1997. It was demonstrated that the impact of agricultural land uses on the environmental quality of the region is very complex, and - although some crops did significantly impact certain aspects, one factor did not overwhelmingly contribute to the overall environmental quality. The evaluation framework was integrated further into a system of modelled cropping practices for optimisation calculations. For this purpose, a model framework was established based on a MS Access database. In the database, cropping practices for 17 crops are stored. Inputs and yields are adapted to the site-specific yield potential. In addition to the cropping practices, the model framework is comprised of an evaluation module and optimisation module. Hence, the impact of the cropping practices can be assessed for each site. This model framework provides the basis for optimisation calculations to forecast various land uses under different conditions. A step-wise integration of the environmental quality goals into the optimisation algorithm of a model farm allows for showing trade-offs between economic and ecological goals. The results of the trade-offs show that an improvement of ecological goal achievement is possible with little impact on the gross margin, as long as the improvement is less than 30% of the starting situation. If improvements greater than 30% are desired, very high losses of gross margin must be taken into consideration. Another result of the calculations shows that high achievements of environmental quality goals often correlate with the percentage of set-aside land within the total area.

IMP3 can predict aggressive behaviour of lung adenocarcinoma

PubMed Central

2012-01-01

Background Lung cancer most often presents as an inoperable tumour and the diagnosis is usually performed on a small biopsy/cytology specimen. In the group of non small cell lung cancer - not otherwise specified, adenocarcinoma phenotype can be determined immunohistochemically using TTF-1 and Napsin A. Expression of oncofetal protein IMP3 in human cancer is associated with poor differentiation and aggressive behaviour. In the present study expression of IMP3 was correlated with expression of TTF-1 and Napsin A, histological subtype and clinical stage of lung adenocarcinoma. We were interested whether distant metastases are associated with IMP3 overexpression, regardless of the histologic subtype of adenocarcinoma. Methods In retrospective study, consecutive series of 105 patients with advanced lung adenocarcinoma diagnosed from 2006 to 2009 in Clinical Hospital Center Split, Croatia, were analysed. Clinical data were collected from the Pulmology Department and time of death from the Mortality Registry. Paraffin blocks of bronchoscopic biopsies were collected from the Institute of Pathology and 15 cases excluded from the analysis due to insufficient material. Expression of IMP3, Napsin A and TTF-1 were analysed by indirect enzyme immunohistochemistry. Statistical analysis was performed and P values less than 0.05 considered significant. Results Of 90 patients, 71 (78%) were males and 19 (22%) females. Median age for males was 61.5 years (min-max 43–83) and for females 61 years (min-max 44–86). Pleural effusion was found in 15 (16.6%) and distant metastases in 45 (50%) cases. According to histological subtypes, there were 34 acinar, 2 lepidic, 2 papillary and 52 solid subtypes. IMP3 overexpression was found in 63 cases (70%) and was correlated with solid subtype (P = 0.002) and negative/weak Napsin A expression (P = 0.004). Strong Napsin A expression correlated with TTF-1 expression (P = 0.003) and lower histological grades (P = 0.031). Patients with IMP3 overexpression more often had distant metastases than patients with negative IMP3, 55.5% versus 33.3% (P = 0.033). Non solid subtypes with IMP3 overexpression developed distant metastasis more common than non solid subtypes with negative IMP3, 72% versus 35% (P = 0.028). Conclusions Expression of IMP3 correlates with solid subtype and with distant metastases regardless of histological subtype of lung adenocarcinoma. Virtual slides http://www.diagnosticpathology.diagnomx.eu/vs/1966211581795258 Zusammenfassung Hintergrund Das Lungenkarzinom kommt meistens als nicht resektabler Tumor vor und die Diagnose kann nur in kleinen Biopsaten oder zytologisch gestellt werden. In der Gruppe der nicht kleinzelligen Lungenkarzinome kann der nicht anders spezifizierte Adenokarzinom Phänotyp mit Hilfe der Antikörper TTF-1 und Napsin A diagnostiziert werden. Die Expression des onkoföetalen Proteins IMP3 ist bei humanen Karzinomen mit agressivem Verhalten und metastatischem Potential verbunden. In dieser Studie korreliert die Expression von IMP3 mit TTF-1, Napsin A, histologischem Typ und klinischem Staging des Lungenkarzinoms. Wir waren daran interessiert, ob Fernmetastasen mit IMP3 Überexpression assoziiert sind, unabhängig von der histologischen Subtyp von Adenokarzinom. Methode In der retrospektiven Studie wurden die von 2006 bis 2009 im Klinischem Krankenhaus Split, Kroatien diagnostizerte Adenokarzinome der Lunge von 105 Patienten analysiert. Die klinischen Daten stammten aus der Abteilung für Pulmologie und im Falle des Todes vom Todesregister. Die Paraffinblöcke der primären Lungenbiopsate dieser Patienten wurden im Institut für Pathologie mit der indirekter Enzym - Immunohistochemie mittels Kombination der Antikörper gegen IMP3, Napsin A und TTF1 untersucht. 15 Fälle aus der Analyse aufgrund unzureichender Material ausgeschlossen. Es wurde eine statistische Untersuchung durchgeführt und Werte weniger als 0.05 P wurden als statistisch signifikant bezeichnet. Ergebnisse Von 90 Patienten mit Lungencarcinom waren 71 (78%) mänlich, durchschnittliches Alter war für Männer 61.5 Jahre (min-max 43–83) und 61 Jahre für Frauen (min-max 44–86). Pleurale Effusionen fand man in 15 Fällen (16.6%) und Fernmetastasen in 45 (50%) Fällen. Histologische Sybtypen waren: 2 lepidic Karzinome, 34 azinäre Karzinome, 2 papilläre und 52 solide Karzinome. IMP3 war exprimiert in 63 Fälle (70%). Positive IMP3 Expression war mit solidem Typ (P = 0.002) und negativer Napsin A Expression (P = 0.004) assoziert. Napsin A Expression war mit niedrigem Gradus (P = 0.031) und positiver TTF-1 Expression (P = 0.003) assoziert. Patienten mit IMP3 Überexpression öfter hatten Fernmetastasen als Patienten mit negativen IMP3, 55.5% versus 33.3% (P = 0.033). Non solide Subtyp mit IMP3 Überexpression entwickelten Fernmetastasen Meer häufiger als nicht festem Subtyp mit negativen IMP3, 72% versus 35% (P = 0.028). Schlussworte Die Expression von IMP3 ist mit negaativer Expression von Napsin A, solidem Subtyp und Metastasen verbunden und hat praktische predictive Werte in der pathologischen Diagnose des Adenokarzinoms der Lunge. Die Expression von IMP3 korreliert mit soliden Subtyp und mit Fernmetastasen unabhängig von histologische Subtyp Lungenadenokarzinom. PMID:23190601

A framework for using connectivity to measure and model water and sediment fluxes

NASA Astrophysics Data System (ADS)

Keessta, Saskia; Saco, Patricia; Nunes, Joao; Parsons, Tony; Poeppl, Ronny; Pereira, Paulo; Novara, Agata; Rodrigo Comino, Jesús; Jordán, Antonio; Masselink, Rens; Cerdà, Artemi

2017-04-01

For many years, scientists have tried to understand, describe and quantify water and sediment fluxes at multiple scales (Cerdà et al., 2013; Parsons et al., 2015; Poeppl et al., 2016; Masselink et al., 2016a; Rodrigo Comino et al., 2016). In the past two decades, a new concept called connectivity has been used by Earth Scientists as a means to describe and quantify the influences on the fluxes of water and sediment on different scales: aggregate, pedon, location on the slope, slope, watershed, and basin (Baartman et al., 2013; Parsons et al., 2015; López-Vicente et al., 2015; 2016; Masselink 2016b; Marchamalo et al., 2016; Mekonnen et al., 2016). A better understanding of connectivity can enhance our comprehension of landscape processes and provide a basis for the development of better measurement and modelling approaches, further leading to a better potential for implementing this concept as a management tool. Our research provides a short review of the State-of-the-Art of the connectivity concept, from which we conclude that scientists have been struggling to find a way to quantify connectivity so far. We adapt the knowledge of connectivity to better understand and quantify water and sediment transfers in catchment systems. First, we introduce a new approach to the concept of connectivity to study water and sediment transfers. In this approach water and sediment dynamics are divided in two parts: the system consists of phases and fluxes, each being separately measurable. This approach enables us to: i) better conceptualize our understanding of system dynamics at different timescales, including long timescales; ii) identify the main parameters driving system dynamics, and devise monitoring strategies which capture them; and, iii) build models with a holistic approach to simulate system dynamics without excessive complexity. Secondly, we discuss the role of system boundaries in designing measurement schemes and models. Natural systems have boundaries within which sediment connectivity varies between phases; in (semi-)arid regions these boundaries can be far apart in time due to extreme events. External disturbances (eg. climate change, changed land management) can change these boundaries. It is therefore important to consider the system state as a whole, including its boundaries and internal dynamics, when designing and implementing comprehensive monitoring and modelling approaches. Keywords: Connectivity, catchment systems, measuring and modelling approaches, co-evolution, management, boundary conditions, fire effects. Acknowledgements This research received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n_ 603498 (RECARE project) and the CGL2013- 47862-C2-1-R and CGL2016-75178-C2-2-R national research projects. References Baartman, J.E.M., Masselink, R.H., Keesstra, S.D., Temme, A.J.A.M., 2013. Linking landscape morphological complexity and sediment connectivity. Earth Surface Processes and Landforms 38: 1457-1471. Cerdà A, Brazier R, Nearing M, de Vente J. 2013. Scales and erosion. CATENA 102: 1-2. DOI: 10.1016/j.catena.2011.09.006 López-Vicente, M., E. Nadal-Romero, and E. L. H. Cammeraat. 2016. Hydrological Connectivity does Change Over 70 Years of Abandonment and Afforestation in the Spanish Pyrenees. Land Degradation and Development. doi:10.1002/ldr.2531. López-Vicente, M., L. Quijano, L. Palazón, L. Gaspar, and A. Navas. 2015. Assessment of Soil Redistribution at Catchment Scale by Coupling a Soil Erosion Model and a Sediment Connectivity Index (Central Spanish Pre-Pyrenees). Cuadernos De Investigacion Geografica 41 (1): 127-147. doi:10.18172/cig.2649. Marchamalo, M., J. M. Hooke, and P. J. Sandercock. 2016. Flow and Sediment Connectivity in Semi-Arid Landscapes in SE Spain: Patterns and Controls. Land Degradation and Development 27 (4): 1032-1044. doi:10.1002/ldr.2352. Masselink RJH, Heckmann T, Temme AJAM, Anders NS, Gooren HPA, Keesstra SD. 2016a. A network theory approach for a better understanding of overland flow connectivity. Hydrological Processes. DOI: 10.1002/hyp.10993 Masselink, R. J. H., S. D. Keesstra, A. J. A. M. Temme, M. Seeger, R. Giménez, and J. Casalí. 2016b. Modelling Discharge and Sediment Yield at Catchment Scale using Connectivity Components. Land Degradation and Development 27 (4): 933-945. doi:10.1002/ldr.2512. Mekonnen, M., Keesstra, S.D., Baartman, J.E.M., Stroosnijder, L., Maroulis, J., Reducing sediment connectivity through man-made and natural sediment sinks in the Minizr catchment, north-west Ethiopia. Accepted to Land Degradation and Development. Parsons A.J., Bracken L., Peoppl , R., Wainwright J., Keesstra, S.D., 2015. Editorial: Introduction to special issue on connectivity in water and sediment dynamics. In press in Earth Surface Processes and Landforms. DOI: 10.1002/esp.3714 Parsons A.J., Bracken L., Peoppl , R., Wainwright J., Keesstra, S.D., 2015. Editorial: Introduction to special issue on connectivity in water and sediment dynamics. In press in Earth Surface Processes and Landforms. DOI: 10.1002/esp.3714 Poeppl, R.,E. Maroulis, J., Keesstra, S.D., 2016. Geomorphology. A conceptual connectivity framework for understanding geomorphic change in human-impacted fluvial systems. http://dx.doi.org/10.1016/j.geomorph.2016.07.033 Rodrigo Comino, J., Iserloh, T., Lassu, T., Cerdà, A., Keesstra, S.D., Prosdocimi, M., Brings, C., Marzen, M., Ramos, M.C., Senciales, J.M., Ruiz Sinoga, J.D., Seeger, M., Ries, J.B., 2016. Quantitative comparison of initial soil erosion processes and runoff generation in Spanish and German vineyards. Science of the Total Environment. In press DOI:10.1016/j.scitotenv.2016.05.163

Seeing a Stellar Explosion in 3D

NASA Astrophysics Data System (ADS)

2010-08-01

Astronomers using ESO's Very Large Telescope have for the first time obtained a three-dimensional view of the distribution of the innermost material expelled by a recently exploded star. The original blast was not only powerful, according to the new results. It was also more concentrated in one particular direction. This is a strong indication that the supernova must have been very turbulent, supporting the most recent computer models. Unlike the Sun, which will die rather quietly, massive stars arriving at the end of their brief life explode as supernovae, hurling out a vast quantity of material. In this class, Supernova 1987A (SN 1987A) in the rather nearby Large Magellanic Cloud occupies a very special place. Seen in 1987, it was the first naked-eye supernova to be observed for 383 years (eso8704), and because of its relative closeness, it has made it possible for astronomers to study the explosion of a massive star and its aftermath in more detail than ever before. It is thus no surprise that few events in modern astronomy have been met with such an enthusiastic response by scientists. SN 1987A has been a bonanza for astrophysicists (eso8711 and eso0708). It provided several notable observational 'firsts', like the detection of neutrinos from the collapsing inner stellar core triggering the explosion, the localisation on archival photographic plates of the star before it exploded, the signs of an asymmetric explosion, the direct observation of the radioactive elements produced during the blast, observation of the formation of dust in the supernova, as well as the detection of circumstellar and interstellar material (eso0708). New observations making use of a unique instrument, SINFONI [1], on ESO's Very Large Telescope (VLT) have provided even deeper knowledge of this amazing event, as astronomers have now been able to obtain the first-ever 3D reconstruction of the central parts of the exploding material. This view shows that the explosion was stronger and faster in some directions than others, leading to an irregular shape with some parts stretching out further into space. The first material to be ejected from the explosion travelled at an incredible 100 million km per hour, which is about a tenth of the speed of light or around 100 000 times faster than a passenger jet. Even at this breakneck speed it has taken 10 years to reach a previously existing ring of gas and dust puffed out from the dying star. The images also demonstrate that another wave of material is travelling ten times more slowly and is being heated by radioactive elements created in the explosion. "We have established the velocity distribution of the inner ejecta of Supernova 1987A," says lead author Karina Kjær. "Just how a supernova explodes is not very well understood, but the way the star exploded is imprinted on this inner material. We can see that this material was not ejected symmetrically in all directions, but rather seems to have had a preferred direction. Besides, this direction is different to what was expected from the position of the ring." Such asymmetric behaviour was predicted by some of the most recent computer models of supernovae, which found that large-scale instabilities take place during the explosion. The new observations are thus the first direct confirmation of such models. SINFONI is the leading instrument of its kind, and only the level of detail it affords allowed the team to draw their conclusions. Advanced adaptive optics systems counteracted the blurring effects of the Earth's atmosphere while a technique called integral field spectroscopy allowed the astronomers to study several parts of the supernova's chaotic core simultaneously, leading to the build-up of the 3D image. "Integral field spectroscopy is a special technique where for each pixel we get information about the nature and velocity of the gas," says Kjær. "This means that besides the normal picture we also have the velocity along the line of sight. Because we know the time that has passed since the explosion, and because the material is moving outwards freely, we can convert this velocity into a distance. This gives us a picture of the inner ejecta as seen straight on and from the side." Notes [1] The team used the SINFONI (Spectrograph for INtegral Field Observations in the Near Infrared) instrument mounted on ESO's Very Large Telescope (VLT). SINFONI is a near-infrared (1.1-2.45 µm) integral field spectrograph fed by an adaptive optics module. More information This research will appear in Astronomy and Astrophysics ("The 3-D Structure of SN 1987A's inner Ejecta", by K. Kjær et al.). The team is composed of Karina Kjær (Queen's University Belfast, UK), Bruno Leibundgut and Jason Spyromilio (ESO), and Claes Fransson and Anders Jerkstrand (Stockholm University, Sweden). ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and VISTA, the world's largest survey telescope. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".

Localised states in organic semiconductors and their detection

NASA Astrophysics Data System (ADS)

Imperia, Paolo

2002-06-01

New polymers and low molecular compounds, suitable for organic light emitting devices and organic electronic applications, have been synthesised in this years in order to obtain electron transport characteristics compatible with requirements for applications in real plastic devices. However, despite of the technological importance and of the relevant progress in devices manufacture, fundamental physical properties of such class of materials are still not enough studied. In particular extensive presence of distributions of localised states inside the band gap has a deep impact on their electronic properties. Such presence of shallow traps as well as the influence of the sample preparation conditions on deep and shallow localised states have not been, until now, systematically explored. The thermal techniques are powerful tools in order to study localised levels in inorganic and organic materials. Thermally stimulated luminescence (TSL), thermally stimulated currents (TSC) and thermally stimulated depolarisation currents (TSDC) allow to deeply look to shallow and deep trap levels as well as they permit to study, in synergy with dielectric spectroscopy (DES), polarisation and depolarisation effects. We studied, by means of numerical simulations, the first and the second order kinetic equations characterised by negligible and strong re-trapping respectively. We included in the equations Gaussian, exponential and quasi-continuous distributions of localised states. The shapes of the theoretical peaks have been investigated by means of systematic variation of the two main parameters of the equations, i. e. the energy trap depth E and the frequency factor a and of the parameters regulating the distributions, in particular for a Gaussian distribution the distribution width s and the integration limits. The theoretical findings have been applied to experimental glow curves. Thin films of polymers and low molecular compounds. Polyphenylquinoxalines, trisphenylquinoxalines and oxadiazoles, studied because of their technological relevance, show complex thermograms, having several levels of localised states and depolarisation peaks. In particular well ordered films of an amphiphilic substituted 2-(p-nitrophenyl)-5-(p-undecylamidophenyl)-1,3,4-oxadiazole (NADPO) are characterised by rich TSL thermograms. A wide region of shallow traps, localised at Em = 4 meV, has been successfully fit by means of a first order kinetic equation having a Gaussian distribution of localised states. Two further peaks, having a different origin, have been characterised. The peaks at Tm = 221.5 K and Tm = 254.2 have activation energy of Em= 0.63 eV and Em = 0.66 eV, frequency factor s = 2.4x1012 s-1 and s = 1.85x1011 s-1, distribution width s = 0.045 eV and s = 0.088 eV respectively. Increasing the number of thermal cycle, a peak, probably connected with structural defects, appears at Tm = 197.7 K. The numerical analysis of this peak was performed by means of a first order equation containing a Gaussian distribution of traps. The activation energy of the trap level is centred at Em = 0.55 eV. The distribution is perfectly symmetric with a quite small width s = 0.028 eV. The frequency factor is s = 1.15 x 1012 s-1, resulting of the same order of magnitude of its neighbour peak at Tm = 221.5 K, having both, probably, the same origin. Furthermore the work demonstrates that the shape of the glow curves is strongly influenced by the excitation temperature and by the thermal cycles. For that reason Gaussian distributions of localised states can be confused with exponential distributions if the previous thermal history of the samples is not adequately considered. In den letzten Jahren ist eine Vielzahl neuer organischer Polymere und niedermolekularer Verbindungen synthetisiert worden, die sich als aktive Komponente für Elektrolumineszenz-Bauelemente und andere elektronische Anwendungen eignen. Trotz der großen technologischen Bedeutung und des erheblichen Fortschrittes, der bei der Herstellung solcher Materialien erzielt worden ist, sind grundlegende physikalische Eigenschaften dieser Materialklassen noch nicht ausreichend erforscht. Insbesondere das Auftreten lokalisierter Zustände innerhalb der Bandlücke hat besondere Bedeutung für ihre elektronischen Eigenschaften. Sowohl die Präsenz dieser flachen traps (Fallen, Löcher) als auch der Einfluß der Herstellungsbedingungen auf die tiefen und flachen lokalisierten Zustände wurden bisher nicht systematisch untersucht. Thermische Techniken sind wichtige Methoden, um lokalisierte Niveaus in organischen und anorganischen Materialien zu erforschen. Themisch-Stimulierte Lumineszenz (TSL), Thermisch-Stimulierte Ströme (TSC) und Thermisch-Stimulierte Depolarisierte Ströme (TSDC) ermöglichen die Untersuchung flacher und tiefer traps; in Verbindung mit DiElektrischer Spektroskopie (DES) können außerdem Polarisations- und Depolarisationseffekte studiert werden. Mit Hilfe numerischer Simulationen haben wir die kinetischen Gleichungen erster und zweiter Ordnung untersucht, die sich durch schwaches bzw. starkes Wieder-Fangen beschreiben lassen. In diesen Gleichungen haben wir Gaussian-, exponentielle und quasi-kontinuierliche Verteilungen von lokalisierten Zustände berücksichtigt. Durch Veränderung der beiden wichtigsten Parameter (Tiefe der traps E und Häufigkeit) konnte die Form der thermischen Maxima untersucht werden. Auch die die Gaussian-Verteilung bestimmenden Faktoren wurden verändert. Diese theoretischen Ergebnisse wurden auf die experimentellen Glow-Kurven angewandt. Dünne Filme aus polymeren und niedermolekularen Verbindungen (Polyphenylquinoxaline, Trisphenylquinoxaline und Oxadiazole), die wegen ihrer technologischen Bedeutung ausgewählt wurden, zeigen komplexes thermisches Verhalten. Insbesondere hoch geordnete Filme eines amphiphil substituierten 2-(p-nitrophenyl)-5-(p-undecylamidophenyl)-1,3,4-oxadiazols (NADPO) zeichnen sich durch komplexe TSL-Diagramme aus. Im Bereich von Em = 4 meV wurde eine Region flacher traps gefunden. Zwei weitere TSL-Maxima treten bei Tm = 221.5 K bzw. Tm = 254.2 K auf. Sie besitzen Aktivierungsenergien von Em= 0.63 eV bzw. Em = 0.66 eV, ihre Frequenzfaktoren betragen s = 2.4x1012 s-1 bzw. s = 1.85x1011 s-1, sie zeigen Breiten der Verteilung von s = 0.045 eV bzw. s = 0.088 eV. Des weiteren zeigt diese Arbeit, daß die Form der Glow-Kurven stark von der Anregungstemperatur und vom thermischen Kreislauf beeinflußt wird.

Efficiency of selection methods for increased ratio of pupal-larval to adult-larval weight gains in Tribolium.

PubMed

Campo, J L; Cobos, P

1994-01-12

Four lines of Tribolium castaneum were selected in each of three replicates for increased ratio of (pupal-larval) to (adult-larval) weight gains, using selection for increased (pupal-larval) weight gain (PL), selection for decreased (adult-larval) weight gain (AL), direct selection for the ratio (R) and linear selection index of larval, pupal and adult weights (I), respectively, for four generations. Linear index was calculated with economic weights of m(2) -m(3) , m(3) -m(1) and m(1) -m(2) , respectively, with m(1) , m(2) and m(3) being the means for larval, pupal and adult weights. Selection to increase the ratio is considered to be a method to maximize the mean response in (adult-larval) weight while controlling the response in (pupal-adult) weight, and as a form of antagonistic selection to increase the weight gain during a given age period relative to the gain at another age period. Larval, pupal and adult weights were measured at 14, 21 and 28 days after adult emergence, respectively. The selected proportion was 20 % in all lines. The response observed for the ratio differed significantly among lines (p < 0.01), with the I and AL lines having the greatest responses. Line R was less effective in improving the objective of selection, while line PL appeared to be inappropriate. The observed responses for the numerator and denominator weight gains were positive in line PL, and negative in the AL, R and I lines. All lines apart from line PL decreased the (adult-larval) weight, holding (pupal-adult) weight constant. Larval weight showed the greatest influence on the response for the objective of selection. The results for this greater than 1 ratio are compared with results of others for smaller than 1 ratios, in which indirect selection for increased numerator is the more efficient alternative to the selection index. ZUSAMMENFASSUNG: Effizienz Selektionsverfahren zur Verbesserung des Quotienten der Gewichtsentwicklung zwischen Puppe/Larve und Käfer/Larve bei Tribolium. In den jeweils drei Versuchsserien zur Erhöhung des Quotienten (Gewicht von Puppe-Larve/Gewicht von Käfer-Larve) wurden vier Versuchsreihen von Tribolium castaneum untersucht: die Versuchsreihe PL wurde gewählt um die Differenz (Puppengewicht-Larvengewicht) zu erhöhen, die Versuchsreihe AL wurde gewählt um die Differenz (Käfergewicht-Larvengewicht) zu reduzieren, die Versuchsreihe R wurde direkt für den Koeffizienten gewählt und die Auswahl der Versuchsreihe I erfolgte über einen linearen Index, errechnet aus dem Gewicht von Larven, Puppen und Käfern über vier Generationen. Der lineare Index wurde berechnet aus den Gewichten von (m(2) -m(3) ), (m(3) -m(1) ) bzw. (m(1) -m(2) ), wobei m(1) , m(2) und m(3) die Mittelwerte für das Gewicht von Larven, Puppen bzw. Käfern sind. Die Auswahl zur Erhöhung des Quotienten ist eine Methode zur Maximierung des Durchschnittsgewichtsverhältnisses Käfer/Larve, sowie eine antagonische Auswahlform zur Erhöhung der Gewichtszunahme während einer bestimmten Wachstumsperiode im Vergleich zur Gewichtszunahme während einer anderen Wachstumsperiode. Das Selektionsverhältnis belief sich auf 20%. Die beim Quotienten beobachtete Antwort wies bedeutende Unterschiede zwischen Versuchsreihen auf (p < 0.01), wobei die höchsten Antworten bei den Versuchsreihen I und AL beobachtet wurden. Versuchsreihe R war am wenigsten effektiv, während Versuchsreihe PL nicht geeignet schien, das Auswahlziel zu verbessern. Die bei Nenner und Zähler beobachteten Antworten waren positiv bei der Versuchsreihe PL und negativ bei den anderen drei Versuchsreihen. Die Ergebnisse für diesen Quotient größer als 1 wurden mit denen anderer Versuche für Quotienten kleiner als 1 verglichen, bei denen die Auswahl zur Erhöhung des Zählers die effizienteste Alternative zum Auswahlindex ist. RESUMEN: Eficiencia de métodos de selección para incrementar el cociente entre la ganancia en peso de pupa-peso de larva y la ganancia en peso de adulto-peso de larva en Tribolium Cuatro líneas de Tribolium castaneum fueron seleccionadas en cada una de tres repeticiones para incrementar el cociente (peso de pupa-peso de larva)/(peso de adulto-peso de larva); la línea PL fue seleccionada para aumentar la diferencia (peso de pupa-pesp de larva), la línea AL fue seleccionada para disminuir la diferencia (peso de adulto-peso de larva), fa línea R fue seleccionada directamente para el cociente, y la línea I fue seleccionada por medio de un índice lineal basado en los pesos de larva, pupa y adulto, durante cuatro generaciones. El índice lineal se calculó con pesos económicos de (m(2) -m(3) ), (m(3) -m(1) ), y (m(1) -m(2) ) respectivamentee, siendo m(1) , m(2) , y m(3) los valores medios para el peso de larva, pupa y adulto. La selección para aumentar el cociente indicado es un método para maximizar la respuesta en (peso de adulto-peso de larva) controlando al tiempo la respuesta en (peso de pupa-peso de adulto), y es una forma de selección antagónica para aumentar la ganancia de peso durante un periodo de edad en relación con la ganancia en peso durante otro periodo. La proporción de selección due el 20 %. La respuesta observada en el cociente difería significativamente entre lineas (p < 0.01), teniendo las líneas I y AL las mayores respuestas. La línea R fue menos efectiva, mientras que la línea PL parecía inapropiada para mejorar el objetiyo de selección. Las respuestas observadas en el denominador y en el numerador fueron positivas en la línea PL, y negativas en las otras tres líneas. Los resultados para este cociente mayor que 1 se comparan con los de otros experimentos para cocientes menores que 1, en los que la selección para incrementar el numerador es la alternativa más eficiente al índice de selección. 1994 Blackwell Verlag GmbH.

Versuche zur Gewinnung von katalytischen Antikörpern zur Hydrolyse von Arylcarbamaten und Arylharnstoffen. (English Title: Attempts to produce catalytic antibodies for hydrolysis of arylcarbamates and arylureas)

NASA Astrophysics Data System (ADS)

Werner, Deljana

2002-05-01

Im Rahmen dieser Arbeit gelang es, katalytische Antikörper zur Hydrolyse von Benzylphenylcarbamaten sowie zahlreiche monoklonale Antikörper gegen Haptene herzustellen. Es wurden verschiedene Hapten-Protein-Konjugate unter Verwendung unterschiedlicher Kopplungsmethoden hergestellt und charakterisiert. Zur Generierung der hydrolytisch aktiven Antikörper wurden Inzuchtmäuse mit KLH-Konjugaten von 4 Übergangszustandsanaloga (ÜZA) immunisiert. Mit Hilfe der Hybridomtechnik wurden verschiedene monoklonale Antikörper gegen diese ÜZA gewonnen. Dabei wurden sowohl verschiedene Immunisierungsschemata als auch verschiedene Inzuchtmausstämme und Fusionstechniken verwendet. Insgesamt wurden 32 monoklonale Antikörper gegen die verwendeten ÜZA selektiert. Diese Antikörper wurden in groen Mengen hergestellt und gereinigt. Zum Nachweis der Antikörper-vermittelten Katalyse wurden verschiedene Methoden entwickelt und eingesetzt, darunter immunologische Nachweismethoden mit Anti-Substrat- und Anti-Produkt-Antikörpern und eine photometrische Methode mit Dimethylaminozimtaldehyd. Der Nachweis der hydrolytischen Aktivität gelang mit Hilfe eines Enzymsensors, basierend auf immobilisierter Tyrosinase. Die Antikörper N1-BC1-D11, N1-FA7-C4, N1-FA7-D12 und R3-LG2-F9 hydrolysierten die Benzylphenylcarbamate POCc18, POCc19 und Substanz 27. Der Nachweis der hydrolytischen Aktivität dieser Antikörper gelang auch mit Hilfe der HPLC. Der katalytische Antikörper N1-BC1-D11 wurde kinetisch und thermodynamisch untersucht. Es wurde eine Michaelis-Menten-Kinetik mit Km von 210 µM, vmax von 3 mM/min und kcat von 222 min-1 beobachtet. Diese Werte korrelieren mit den Werten der wenigen bekannten Diphenylcarbamat-spaltenden Abzyme. Die Beschleunigungsrate des Antikörpers N1-BC1-D11 betrug 10. Das ÜZA Hei3 hemmte die hydrolytische Aktivität. Dies beweist, dass die Hydrolyse in der Antigenbindungsstelle stattfindet. Weiter wurde zwischen der Antikörperkonzentration und der Umsatzgeschwindigkeit eine lineare Abhängigkeit festgestellt. Die thermodynamische Gleichtgewichtsdissoziationskonstante KD des Abzyms von 2,6 nM zeugt von einer sehr guten Affinität zum ÜZA. Hydrolytisch aktiv waren nur Antikörper, die gegen das Übergangszustandsanalogon Hei3 hergestellt worden waren. Es wird vermutet, dass die Hydrolyse der Benzylphenylcarbamate über einen Additions-Eliminierungsmechanismus unter Ausbildung eines tetraedrischen Übergangszustandes verläuft, dessen analoge Verbindung Hei3 ist. Im Rahmen der Generierung von Nachweisantikörpern zur Detektion der Substratabnahme bei der Hydrolyse wurden Anti-Diuron-Antikörper hergestellt. Einer der Antikörper (B91-CG5) ist spezifisch für das Herbizid Diuron und hat einen IC50-Wert von 0,19 µg/l und eine untere Nachweisgrenze von 0,04 µg/l. Ein anderer Antikörper (B91-KF5) reagiert kreuz mit einer Palette ähnlicher Herbizide. Mit diesen Antikörpern wurde ein empfindlicher Labortest, der ein Monitoring von Diuron auf Grundlage des durch die Trinkwasserverordnung festgeschriebenen Wertes für Pflanzenschutzmittel von 0,1 µg/l erlaubt, aufgebaut. Der Effekt der Anti-Diuron-Antikörper auf die Diuron-inhibierte Photosynthese wurde in vitro und in vivo untersucht. Es wurde nachgewiesen, dass sowohl in isolierten Thylakoiden, als auch in intakten Algen eine Vorinkubation der Anti-Diuron-Antikörper mit Diuron zur Inaktivierung seiner Photosynthese-hemmenden Wirkung führt. Wurde der Elektronentransport in den isolierten Thylakoiden oder in Algen durch Diuron unterbrochen, so führte die Zugabe der Anti-Diuron-Antikörper zur Reaktivierung der Elektronenübertragung. Attempts to produce catalytic antibodies for hydrolysis of arylcarbamates and arylureas: The aim of the investigations was to produce antibodies which are able to cleave herbicides resistant to naturally occuring enzymes. Structurally similar carbamate and urea derivatives were chosen for the experiments. Phosphonate derivatives were synthesized that mimick possible transition state analogues in structure and charge. Mice were immunized with 4 different derivatives after conjugating them to carrier proteins. 32 hybridomas were established that produce monoclonal antibodies binding to these derivatives. The possible cleavage of substrates was determined by immunoassays with monoclonal antibodies against the substrate and the products and with a photometric method based on dimethylaminocinammonaldehyde. The measuring of cleavage products was succeeded by an amperometric method. The enzyme sensor was based on immobilized tyrosinase which oxidizes p-chlorophenol and phenol. The antibodies N1-BC1-D11, N1-FA7-C4, N1-FA7-D12 und R3-LG2-F9 hydrolysed the benzylphenylcarbamates POCc18, POCc19 und Substance 27. The hydrolytic activity of these antibodies was also succeeded with HPLC. The catalytic antibody N1-BC1-D11 was investigated kinetically and thermodynamically. A Michaelis-Menten-Kinetic was observed (at pH 8.0 exhibited a Km 210 µM, a vmax 3 mM/min and a kcat 222 min-1). These values are in the range of the values obtained for the antibody-catalysed hydrolysis of diphenylcarbamates. The rate enhancement of N1-BC1 was 10. The reaction was completely inhibited by stoichiometric quantities of the transition state analogue Hei3. This is consistent with the affinity of the abzyme to Hei3 of 2.6 nM, determined by BIAcore assay. Only antibodies generated against Hei3 showed hydrolytic activity. The hydrolysis of benzylphenylcarbamates presumably occurs via an addition-elimination-Mechanism involving a tetrahedral intermediate. In summary, this work presents the first example of antibody-catalysed hydrolysis of benzylphenylcarbamates. Monoclonal anti-diuron antibodies were generated that bind to the herbicide diuron with an extremely low equilibrium dissociation constant. A sensitive immunoassay with a low detection limit of 0.2 nM for diuron was established. This is the most sensitive immunological method for detection of diuron known so far. These antibodies were also used in vitro and in vivo to prevent diuron-dependent inhibition of photosynthesis or to restore photosynthesis after inhibition. In isolated thylakoids prepared from spinach leaves (Spinacia oleracea L.) the diuron-inhibited Hill reaction was reconstituted immediately following the addition of the monoclonal antibodies. In an in vivo approach the photosynthetic oxygen evolution of the cell wall deficient mutant (cw 15) of the green alga Chlamydomonas reinhardtii Dangeard was monitored. The antibodies prevented the diuron-dependent inhibition of photosynthesis and restored photosynthesis after inhibition. Transgenic plants that synthesize and accumulate these antibodies or antibody fragments and are therefore diuron-resistant can be created.

Obituary: Hakki Ogelman (1940-2011)

NASA Astrophysics Data System (ADS)

Orio, Marina

2011-12-01

Hakki Boran Ögelman died in Austin, Texas, on September 4, 2011, after battling esophageal cancer for several months. Hakki was born in Ankara, Turkey, on July 8, 1940, and was the son of Salehettin Ögelman, a lawyer, and Vedya Özlem Ögelman, a schoolteacher. He had a sister, older by three years, the late Esen Yerliçi. Soon after his birth, the family moved to Istanbul, where Hakki attended the Robert College from sixth grade and obtained an international baccalaureate at age 17. In the same year, he moved to the United States to further his education at DePaw University in Indiana, where he obtained a Bachelor's Degree in three years and developed a strong passion for physics. He was accepted as a graduate student in physics at Cornell University, where he was fortunate to have such professors as Hans Bethe and Ed Salpeter, among others. Hakki's advisor, Kenneth Greisen, had worked on the Manhattan Project and was a leading expert in the study of charged particles from space and gamma rays from astronomical sources. For his Ph.D., Hakki flew a balloon experiment to measure gamma rays at the highest energy, deriving from the radioactive decay of elementary particles from space. Hakki received his Ph.D. from Cornell in February of 1966. After a postdoctoral year working on gamma ray astrophysics at the University of Sydney in Australia, Hakki accepted a fellowship at NASA's Goddard Space Flight Center where he became an expert on pulsars and wrote a series of articles published by Nature on astronomical sources of gamma rays. At age 30, Hakki declined the offer of a civil service position at NASA and left for Turkey, feeling he wanted to give back to his home country, which had given him a strong education and instilled in him core values. After a period in the military as an officer, he was offered a position at the Middle East Technical University (METU) of Ankara, an English speaking university. After becoming a full professor at METU and spending a sabbatical year back at Goddard, Hakki took leave from Ankara to help the development of a university in the rural area of Adana and became the Dean of Basic Sciences at Çukurova University. He established a group working on exploitation techniques of solar energy and planned for himself and his wife a solar house that was built on campus. Hakki was a member of the Turkish Academy of Sciences, served as a member of the Executive Science Board for the Scientific and Technical Research Council of Turkey from 1976-1984, and represented Turkey on international science councils and co-operations. Turkey during those years was in turmoil, first apparently on the brink of a civil war and later governed by a strict military regime. Upsetting personal experiences convinced Hakki that Turkey had become too difficult for a free intellectual person, so he took a prolonged sabbatical at the Max Planck Institute for Extraterrestrial Physics in Garching near Munich, where he had already spent several summers and kept in touch with an international and vibrant community of scientists working on high-energy astrophysics. What started as a sabbatical stretched into almost 8 years. From gamma rays he moved to lower energies, X-rays, and made several interesting discoveries first with EXOSAT, then with ROSAT, the second imaging telescope in X-rays. Hakki was broadly educated across many areas of physics, astronomy and science in general. He was very curious and an avid reader of science and non-science books and articles. Such broad horizons helped him think "outside the box." He was the first to observe novae as accreting and exploding white dwarfs in binary systems in X-rays, thereby observing the "naked white dwarf" to obtain clues on its mass, chemical composition and possible evolutionary path toward a supernova Ia explosion. Hakki's work on cooling neutron stars, pulsars and their nebulae (his main interest) was always innovative. One difficult riddle he hoped to solve was the relationship between the mass and radius of a neutron star in order to infer the equation of state of neutron stars and whether they contain exotic particles. He was particularly interested in the glitches of neutron stars (sudden small increases in the rotation speed) because these may be caused by transitions of vortices in the superfluid core of the star. Turkey recognized Hakki as an outstanding scientist, and he was awarded the Sedat Simavi Prize in 1988 and the Turkish Scientific and Technical Research Council Prize in 1991. Eventually, Hakki returned to the U.S. where he felt that scientific life was most lively and interesting. He accepted a position as professor of physics at the University of Wisconsin in Madison at the beginning of 1991. Working with ROSAT, he made new discoveries related to neutron stars and novae. He mentored five successful graduate students and a post-doctoral associate, worked with countless collaborators, and was loved by his students in Wisconsin. He bought a house on Lake Monona in Madison because "being on water was important to him and reminded him of the Bosphorus." He visited Turkey for a long time every summer, worked with students and collaborators there, and was instrumental in establishing the Turkish National Observatory. In 1996, while he was at the peak of his career and his third son was just a year and a half old, Hakki's life was disrupted by a massive stroke. He became physically handicapped and had to slow his pace somewhat. He was able to go back to teaching and still carried on independent and original research, but he had to take time to rest after each activity. He taught at the University of Wisconsin until March of 2011, even after heart surgery a year earlier. Eventually, an aggressive form of cancer caught up with his energy and love of science and life. Hakki had been married three times, each marriage lasting for more than 10 years. He is survived by three sons and a daughter-in-law, Kenan Ögelman of Austin, Texas, Nedim and Laura Ögelman of Alexandria, Virginia, and Roberto Ögelman of Madison, Wisconsin, and two grandsons, Anders and Soren Ögelman, of Alexandria, Virginia. His family, friends and colleagues will miss Hakki's inquisitive spirit.

Interplanetary Dust Particles

NASA Astrophysics Data System (ADS)

Bradley, J. P.

2003-12-01

One of the fundamental goals of the study of meteorites is to understand how the solar system and planetary systems around other stars formed. It is known that the solar system formed from pre-existing (presolar) interstellar dust grains and gas. The grains originally formed in the circumstellar outflows of other stars. They were modified to various degrees, ranging from negligible modification to complete destruction and reformation during their ˜108 yr lifetimes in the interstellar medium (ISM) (Seab, 1987; Mathis, 1993). Finally, they were incorporated into the solar system. Submicrometer-sized silicates and carbonaceous material are believed to be the most common grains in the ISM ( Mathis, 1993; Sandford, 1996), but it is not known how much of this presolar particulate matter was incorporated into the solar system, to what extent it has survived, and how it might be distinguished from solar system grains. In order to better understand the process of solar system formation, it is important to identify and analyze these solid grains. Since all of the alteration processes that modified solids in the solar nebula presumably had strong radial gradients, the logical place to find presolar grains is in small primitive bodies like comets and asteroids that have undergone little, if any, parent-body alteration.Trace quantities of refractory presolar grains (e.g., SiC and Al2O3) survive in the matrices of the most primitive carbon-rich chondritic meteorites (Anders and Zinner, 1993; Bernatowicz and Zinner, 1996; Bernatowicz and Walker, 1997; Hoppe and Zinner, 2000; see Chapter 1.02). Chondritic meteorites are believed to be from the asteroid belt, a narrow region between 2.5 and 3.5 astronomical units (AU) that marks the transition from the terrestrial planets to the giant gas-rich planets. The spectral properties of the asteroids suggest a gradation in properties with some inner and main belt C and S asteroids (the source region of most meteorites and polar micrometeorites) containing layer silicates indicative of parent-body aqueous alteration and the more distant anhydrous P and D asteroids exhibiting no evidence of (aqueous) alteration (Gradie and Tedesco, 1982). This gradation in spectral properties presumably extends several hundred AU out to the Kuiper belt, the source region of most short-period comets, where the distinction between comets and outer asteroids may simply be one of the orbital parameters ( Luu, 1993; Brownlee, 1994; Jessberger et al., 2001). The mineralogy and petrography of meteorites provides direct confirmation of aqueous alteration, melting, fractionation, and thermal metamorphism among the inner asteroids ( Zolensky and McSween, 1988; Farinella et al., 1993; Brearley and Jones, 1998). Because the most common grains in the ISM (silicates and carbonaceous matter) are not as refractory as those found in meteorites, it is unlikely that they have survived in significant quantities in meteorites. Despite a prolonged search, not a single presolar silicate grain has yet been identified in any meteorite.Interplanetary dust particles (IDPs) are the smallest and most fine-grained meteoritic objects available for laboratory investigation (Figure 1). In contrast to meteorites, IDPs are derived from a broad range of dust-producing bodies extending from the inner main belt of the asteroids to the Kuiper belt (Flynn, 1996, 1990; Dermott et al., 1994; Liou et al., 1996). After release from their asteroidal or cometary parent bodies the orbits of IDPs evolve by Poynting-Robertson (PR) drag (the combined influence of light pressure and radiation drag) ( Dermott et al., 2001). Irrespective of the location of their parent bodies nearly all IDPs under the influence of PR drag can eventually reach Earth-crossing orbits. IDPs are collected in the stratosphere at 20-25 km altitude using NASA ER2 aircraft ( Sandford, 1987; Warren and Zolensky, 1994). Laboratory measurements of implanted rare gases, solar flare tracks ( Figure 2), and isotope abundances have confirmed that the collected particles are indeed extraterrestrial and that, prior to atmospheric entry, they spent 104-105 yr as small particles orbiting the Sun (Rajan et al., 1977; Hudson et al., 1981; Bradley et al., 1984a; McKeegan et al., 1985; Messenger, 2000). (21K)Figure 1. (a)-(c) Secondary electron images. (a) Anhydrous CP IDP. (b) Hydrated CS IDP (RB12A44). (c) Single-mineral forsterite grain with adhering chondritic material. (d) Optical micrograph (transmitted light) of giant cluster IDP (U220GCA) in silicone oil on ER2 collection flag. (14K)Figure 2. Darkfield transmission electron micrographs. (a) Solar-wind sputtered rim on exterior surface plus implanted solar flare tracks in chondritic IDP U220A19 (from Bradley and Brownlee, 1986). (b) Solar flare tracks in a forsterite crystal in chondritic IDP U220B11 (from Bradley et al., 1984a). The track densities in both IDPs are ˜1010-1011 cm2 corresponding to an orbital exposure age of ˜104yr. During atmospheric entry most IDPs are frictionally heated to within 100 °C of their peak heating temperature for ˜1 s and, to a first-order approximation, the smallest particles are the least strongly heated. Although some IDPs may experience thermal pulses in excess of 1,000 °C for up to 10 s (depending on particle size, mass, entry angle, and speed) (Love and Brownlee, 1991, 1996), the presence of solar flare tracks in an IDP establishes that it was not heated above ˜650 °C ( Bradley et al., 1984a). Since IDPs decelerate from cosmic velocities at altitudes >90 km, where the maximum aerodynamic ram pressure is a factor of ˜103 less than that exerted on conventional meteorites, extremely fragile meteoritic materials that cannot survive as large objects can survive as small IDPs (Figure 1(a)) ( Brownlee, 1994). Such fragile materials are suspected to be among the most primitive objects and potentially the most informative regarding early solar system and presolar processes. (Conventional meteorites penetrate deep into the atmosphere such that only relatively well-indurated rocks can survive.) Collected IDPs are briefly exposed to the terrestrial environment but since their residence time in the stratosphere is short (˜2 weeks), they are not subjected to longer-term weathering that affects the surfaces of most meteorites (Flynn, 1994a).This chapter examines the compositions, mineralogy, sources, and geochemical significance of IDPs. Additional reading can be found in reviews by Fraundorf (1981), Brownlee (1985), Sandford (1987), Bradley et al. (1988), Jessberger et al. (2001), Rietmeijer (1998), and the book edited by Zolensky et al. (1994). Despite their micrometer-scale dimensions and nanogram masses it is now possible, primarily as a result of advances in small particle handling techniques and analytical instrumentation, to examine IDPs at close to atomic-scale resolution. The most widely used instruments for IDP studies are presently the analytical electron microscope, synchrotron facilities, and the ion microprobe. These laboratory analytical techniques are providing fundamental insights about IDP origins, mechanisms of formation, and grain processing phenomena that were important in the early solar system and presolar environments. At the same time, laboratory data from IDPs are being compared with astronomical data from dust in comets, circumstellar disks, and the ISM. The direct comparison of grains in the laboratory with grains in astronomical environments defines the new discipline of "astromineralogy" ( Jaeger et al., 1998; Bradley et al., 1999a, b; Molster et al., 2001; Keller et al., 2001; Flynn et al., 2002). ,

Change in genetic correlation due to selection using animal model evaluation.

PubMed

Strandén, I; Mäntysaari, E A; Mäki-Tanila, A

1993-01-12

Monte Carlo simulation and analytical calculations were used to study the effect of selection on genetic correlation between two traits. The simulated breeding program was based on a closed adult multiple ovulation and embryo transfer nucleus breeding scheme. Selection was on an index calculated using multi-trait animal model (AM). Analytical formulae applicable to any evaluation method were derived to predict change in genetic (co)variance due to selection under multi-trait selection using different evaluation methods. Two formulae were investigated, one assuming phenotypic selection and the other based on a recursive two-generation AM selection index. The recursive AM method approximated information due to relatives by a relationship matrix of two generations. Genetic correlation after selection was compared under different levels of initial genetic and environmental correlations with two different selection criteria. Changes in genetic correlation were similar in simulation and analytical predictions. After one round of selection the recursive AM method and the simulation gave similar predictions while the phenotypic selection predicted usually more change in genetic correlation. After several rounds of selection both analytical formulae predicted more change in genetic correlation than the simulation. ZUSAMMENFASSUNG: Änderung der genetischen Korrelation bei Selektion mit einem Tiermodell Der Selektionseffekt auf die genetische Korrelation zwischen zwei Merkmalen wurde mit Hilfe von Monte Carlo-Simulation und analytischen Berechnungen untersucht. Ein geschlossener Adulter - MOET (Multiple Ovulation and Embryo Transfer) Zuchtplan wurde simuliert. Die Selektion gründete sich auf einen Index, der die Zuchtwertschätzung des Mehrmerkmals-Tiermodells benutzte. Analytische Formeln für die Voraussage der Änderung der genetischen (Ko)varianz unter multivariate Selektion für verschiedene Zuchtwertschätzungsmethode wurden deduziert. Zwei Formeln wurden studiert, die erste nahm phänotypische Auswahl an und die andere gründete sich auf ein wiederholte Mehrmerkmals-Tiermodell von zwei Generationen. Das wiederholte Mehrmerkmals-Tiermodell approximierte die Information aus den Verwandten mit Hilfe einer Verwandtschaftsmatrix der zwei Generationen. Die genetische Korrelation nach der Selektion aus der Simulation und den analytischen Formeln wurde mit verschiedenen reellen genetischen und umweltbedingten Korrelationen mit zwei Selektionskriterien verglichen. Sie änderte sich ähnlich bei Simulation und analytischen Formeln. Nach einem Selektionszyklus kamen das wiederholte Mehrmerkmals-Tiermodell und die Simulation zu gleichen Voraussagen, aber die phänotypische Selektion sagte mehr Änderung voraus. Nach mehreren selektierten Generationen sagten die beiden analytischen Formeln mehr Änderung in der genetischen Korrelation voraus als die Simulation. RÉSUMÉ: Changement de corrélation génétique du à la sélection en utilisant une évaluation de type modèle animal Une simulation Monte Carlo et des calculs analytiques ont été utilisés pour étudier l'effet de la sélection sur la corrélation génétique entre deux caractères. Le programme de sélection simulé a été basé sur le schéma d'un noyau de sélection adulte et fermé avec superovulation et transfert embryonnaire. La sélection portait sur un indice calculé à partir d'un modèle animal multicaractères (AM). Des formules analytiques applicables à n'importe quelle méthode d'évaluation ont été développées pour prédire le changement de (co)variance génétique du à la sélection multicaractères en utilisant différentes méthodes d'évaluation. Deux formules ont été étudiées, l'une supposant une sélection phénotypique et l'autre basée sur un index de sélection de type AM sur deux générations. La méthode AM récurrente prenait en compte l'information des apparentés de manière approximative à travers la matrice de parenté sur deux générations. La corrélation génétique après sélection a été comparée à différents niveaux de corrélations génétique et environnementale pour deux critères de sélection différents. Les changements de corrélation génétique étaient similaires dans les simulations et les prédictions analytiques. Après un cycle de sélection, la méthode récurrente AM et la simulation donnaient les prédictions similaires alors que la sélection phénotypique prédisait habituellement des changements de corrélations génétiques plus importants. Après plusieurs cycles de sélection, les deux formules analytiques prédisaient des changements de corrélation plus importants que la simulation. RÉSUMÉ: Cambio en la correlación genética debido a selección usando evaluaciones con modelo animal Se estudió el efecto de la selección sobre la correlación genética entre dos caracteres utilizando simulación de Monte Carlo y cálculos analíticos. El esquema de selección simulado estuvo basado en un núcleo adulto y cerrado de ovulación multiple y transferencia de embriones. El criterio de selección fue un indice calculado a partir de un modelo animal multicarácter (AM). Se derivaron fórmulas analíticas aplicables a cualquier método de evaluación para predecir cambios debidos a selección en las (co)varianzas genéticas bajo selección multicarácter usando distintos métodos de valoración. Se investigaron dos fórmulas, una que asumía selección fenotípica y la otra basada en un índice de selección AM recurrente con dos generaciones. El método AM recurrente aproximaba la información de parientes a través de una matriz de relaciones aditivas que contemplaba dos generaciones. La correlación genética tras la selección fue comparada bajo distintos niveles de correlación genética y ambiental iniciales con dos criterios de selección diferentes. Los cambios en correlatión genética fueron similares en las predicciones analíticas y con simulación. Tras un ciclo de selección, el método AM recurrente y la simulación produjeron predicciones similares mientras que la selección fenotípica predijo, generalmente, más cambio en la correlación genética. Después de varios ciclos de selección, las dos fórmulas analíticas predijeron más cambios en la correlación genética que la simulación. 1993 Blackwell Verlag GmbH.

Electron acceleration at localized wave structures in the solar corona (German Title: Elektronenbeschleunigung an lokalen Wellenstrukturen in der Sonnenkorona)

NASA Astrophysics Data System (ADS)

Miteva, Rositsa Stoycheva

2007-07-01

Our dynamic Sun manifests its activity by different phenomena: from the 11-year cyclic sunspot pattern to the unpredictable and violent explosions in the case of solar flares. During flares, a huge amount of the stored magnetic energy is suddenly released and a substantial part of this energy is carried by the energetic electrons, considered to be the source of the nonthermal radio and X-ray radiation. One of the most important and still open question in solar physics is how the electrons are accelerated up to high energies within (the observed in the radio emission) short time scales. Because the acceleration site is extremely small in spatial extent as well (compared to the solar radius), the electron acceleration is regarded as a local process. The search for localized wave structures in the solar corona that are able to accelerate electrons together with the theoretical and numerical description of the conditions and requirements for this process, is the aim of the dissertation. Two models of electron acceleration in the solar corona are proposed in the dissertation: I. Electron acceleration due to the solar jet interaction with the background coronal plasma (the jet--plasma interaction) A jet is formed when the newly reconnected and highly curved magnetic field lines are relaxed by shooting plasma away from the reconnection site. Such jets, as observed in soft X-rays with the Yohkoh satellite, are spatially and temporally associated with beams of nonthermal electrons (in terms of the so-called type III metric radio bursts) propagating through the corona. A model that attempts to give an explanation for such observational facts is developed here. Initially, the interaction of such jets with the background plasma leads to an (ion-acoustic) instability associated with growing of electrostatic fluctuations in time for certain range of the jet initial velocity. During this process, any test electron that happen to feel this electrostatic wave field is drawn to co-move with the wave, gaining energy from it. When the jet speed has a value greater or lower than the one, required by the instability range, such wave excitation cannot be sustained and the process of electron energization (acceleration and/or heating) ceases. Hence, the electrons can propagate further in the corona and be detected as type III radio burst, for example. II. Electron acceleration due to attached whistler waves in the upstream region of coronal shocks (the electron--whistler--shock interaction) Coronal shocks are also able to accelerate electrons, as observed by the so-called type II metric radio bursts (the radio signature of a shock wave in the corona). From in-situ observations in space, e.g., at shocks related to co-rotating interaction regions, it is known that nonthermal electrons are produced preferably at shocks with attached whistler wave packets in their upstream regions. Motivated by these observations and assuming that the physical processes at shocks are the same in the corona as in the interplanetary medium, a new model of electron acceleration at coronal shocks is presented in the dissertation, where the electrons are accelerated by their interaction with such whistlers. The protons inflowing toward the shock are reflected there by nearly conserving their magnetic moment, so that they get a substantial velocity gain in the case of a quasi-perpendicular shock geometry, i.e, the angle between the shock normal and the upstream magnetic field is in the range 50--80 degrees. The so-accelerated protons are able to excite whistler waves in a certain frequency range in the upstream region. When these whistlers (comprising the localized wave structure in this case) are formed, only the incoming electrons are now able to interact resonantly with them. But only a part of these electrons fulfill the the electron--whistler wave resonance condition. Due to such resonant interaction (i.e., of these electrons with the whistlers), the electrons are accelerated in the electric and magnetic wave field within just several whistler periods. While gaining energy from the whistler wave field, the electrons reach the shock front and, subsequently, a major part of them are reflected back into the upstream region, since the shock accompanied with a jump of the magnetic field acts as a magnetic mirror. Co-moving with the whistlers now, the reflected electrons are out of resonance and hence can propagate undisturbed into the far upstream region, where they are detected in terms of type II metric radio bursts. In summary, the kinetic energy of protons is transfered into electrons by the action of localized wave structures in both cases, i.e., at jets outflowing from the magnetic reconnection site and at shock waves in the corona. Die Sonne ist ein aktiver Stern, was sich nicht nur in den allseits bekannten Sonnenflecken, sondern auch in Flares manifestiert. Während Flares wird eine große Menge gespeicherter, magnetischer Energie in einer kurzen Zeit von einigen Sekunden bis zu wenigen Stunden in der Sonnenkorona freigesetzt. Dabei werden u.a. energiereiche Elektronen erzeugt, die ihrerseits nichtthermische Radio- und Röntgenstrahlung, wie sie z.B. am Observatorium für solare Radioastronomie des Astrophysikalischen Instituts Potsdam (AIP) in Tremsdorf und durch den NASA-Satelliten RHESSI beobachtet werden, erzeugen. Da diese Elektronen einen beträchtlichen Anteil der beim Flare freigesetzten Energie tragen, ist die Frage, wie Elektronen in kurzer Zeit auf hohe Energien in der Sonnenkorona beschleunigt werden, von generellem astrophysikalischen Interesse, da solche Prozesse auch in anderen Sternatmosphären und kosmischen Objekten, wie z.B. Supernova-Überresten, stattfinden. In der vorliegenden Dissertation wird die Elektronenbeschleunigung an lokalen Wellenstrukturen im Plasma der Sonnenkorona untersucht. Solche Wellen treten in der Umgebung der magnetischen Rekonnektion, die als ein wichtiger Auslöser von Flares angesehen wird, und in der Nähe von Stoßwellen, die infolge von Flares erzeugt werden, auf. Generell werden die Elektronen als Testteilchen behandelt. Sie werden durch ihre Wechselwirkung mit den elektrischen und magnetischen Feldern, die mit den Plasmawellen verbunden sind, beschleunigt. Infolge der magnetischen Rekonnektion als Grundlage des Flares werden starke Plasmaströmungen (sogenannte Jets) erzeugt. Solche Jets werden im Licht der weichen Röntgenstrahlung, wie z.B. durch den japanischen Satelliten YOHKOH, beobachtet. Mit solchen Jets sind solare Typ III Radiobursts als Signaturen von energiereichen Elektronenstrahlen in der Sonnenkorona verbunden. Durch die Wechselwirkung eines Jets mit dem umgebenden Plasma werden lokal elektrische Felder erzeugt, die ihrerseits Elektronen beschleunigen können. Dieses hier vorgestellte Szenarium kann sehr gut die Röntgen- und Radiobeobachtungen von Jets und den damit verbundenen Elektronenstrahlen erklären. An koronalen Stoßwellen, die infolge Flares entstehen, werden Elektronen beschleunigt, deren Signatur man in der solaren Radiostrahlung in Form von sogenannten Typ II Bursts beobachten kann. Stoßwellen in kosmischen Plasmen können mit Whistlerwellen (ein spezieller Typ von Plasmawellen) verbunden sein. In der vorliegenden Arbeit wird ein Szenarium vorgestellt, das aufzeigt, wie solche Whistlerwellen an koronalen Stoßwellen erzeugt werden und durch ihre resonante Wechselwirkung mit den Elektronen dieselben beschleunigen. Dieser Prozess ist effizienter als bisher vorgeschlagene Mechanismen und kann deshalb auch auf andere Stoßwellen im Kosmos, wie z.B. an Supernova-Überresten, zur Erklärung der dort erzeugten Radio- und Röntgenstrahlung dienen.

News and Announcements

NASA Astrophysics Data System (ADS)

1999-05-01

Supplementary Materials The number of supplementary materials that accompany print articles has grown and also become more varied. The new guidelines for lab experiments call for supplementary materials in most cases, so that the actual materials used in lab can be made available. The From Past Issues column edited by Kathryn Williams and many of the technology columns frequently have supplements for JCE Online. An especially interesting supplement that we would like to call to the attention of readers is a collection of videos from the E. O. Lawrence Berkeley National Laboratory, based on interviews with nuclear chemists who have discovered and studied the heaviest elements. These movies accompany the Viewpoints article, "Chemistry of the Heaviest Elements-One Atom at a Time" by Darleane C. Hoffman and Diana M. Lee. The titles of the movies are listed below; illustrative stills are shown at the bottom of the page. Researchers involved with the segments about Lawrencium include Robert Silva, Torbjorn Sikkeland, Matti Nurmia, Robert Latimer, and Albert Ghiorso, all of whom are from the Lawrence Berkeley Laboratory. (QuickTime 3 is needed in order to view the videos; it can be downloaded free from http://www.apple.com.)

• A Brief Note about Plutonium, by Glenn Seaborg
• Plutonium and Why It Was Kept a Secret
• The Prediction of the Actinide Series, by Glenn Seaborg
• First Chemical Separation of Lawrencium at Lawrence Radiation Laboratory in 1970
• The HILAC or Heavy-Ion Linear Accelerator
• Discovery of Lawrencium
• How To Collect Lawrencium Atoms
• The Discovery of Element 106-Finally
• The Naming of Element 106
• The Limits of Discovering the Heavy Elements
• What Good Is a Heavy Element?

June 16-19: TBA, Minneapolis, MN June 23-26: Southwest Texas State Univ., San Marcos, TX July 7-10: University of Nevada-Reno, Reno, NV July 14-17: Northeastern University, Boston, MA August 3-6: College of Charleston, Charleston, SC August 16-19: TBA, Seattle, WA

• Course, Curriculum, and Laboratory Improvement (CCLI) June 7, 1999
• NSF Collaboratives for Excellence in Teacher Preparation (CETP) Preliminary proposals, Track 1 May 1, 1999 Formal proposals, Track 1 September 1, 1999
• DUE online 1999 guidelines, NSF 99-53 available at http://www.nsf.gov/cgi-bin/getpub?nsf9953

• Camille Dreyfus Teacher-Scholar Awards Program: November 16, 1998
• Henry Dreyfus Teacher-Scholar Awards Program: July 1, 1999
• New Faculty Awards Program: May 14, 1999
• Faculty Start-up Grants for Undergraduate Institutions: May 14, 1999
• Scholar/Fellow Program for Undergraduate Institutions: July 1, 1999
• Special Grant Program in the Chemical Sciences: July 15, 1999
• Postdoctoral Program in Environmental Chemistry: February 26, 1999

• Cottrell College Science Awards: May 15 and November 15
• Cottrell Scholars: First regular business day in September
• Partners in Science: December 1 (the final year for this program is summer 1999)
• Research Opportunity Awards: May 1 and October 1
• Research Innovation Awards: May 1

FOREWORD: The 70th birthday of Professor Stig Stenholm The 70th birthday of Professor Stig Stenholm

NASA Astrophysics Data System (ADS)

Suominen, Kalle-Antti

2010-09-01

It is not easy to assess, or even to describe correctly a long and distinguished career that started about the time when I was born. In 1964 Stig Stenholm got both an engineering degree at the Helsinki University of Technology (HUT), and an MSc degree (in Mathematics) at the University of Helsinki. The two degrees demonstrate Stig's ability to understand both complex mathematics and experimental physics. Statistical physics or rather, quantum liquids, was the field in which Stig got his DPhil at Oxford in 1967, under the guidance of Dirk ter Haar. It is interesting that together they worked on studying fermions in a bosonic background [1]; at the time this meant, of course, 3He atoms as impurities in 4He liquid, but nowadays one would immediately connect such systems to the physics of cold atomic gases. The postdoctoral period in 1967-1968 at Yale University brought Stig in contact with Willis Lamb and laser physics [2]. Back in Finland, Stig's career in the 1970s was dominated by theoretical studies of gas lasers, especially pressure and collision effects on spectral lines and saturation spectroscopy, together with his first PhD student, Rainer Salomaa. A professorship at the University of Helsinki came in 1974, and in 1980 an important era started as Stig became the scientific director of the Research Institute for Theoretical Physics (TFT). At that time he also developed the semiclassical theory of laser cooling especially with Juha Javanainen. The laser spectroscopy work led to a textbook in 1984 [3], and the semiclassical laser cooling theory was summarized in a review article in 1986 [4]. These were not, of course, his only interests, as he also worked on free-electron lasers, ring-laser gyroscopes, multiphoton processes and quantum amplifiers. In an article written in 1990 in honour of Olli Lounasmaa [5], the founder of the famous Low Temperature Laboratory at HUT, Stig mentions that one of his most memorable achievements was acting as a bridge between the Western and Soviet laser cooling communities. In neutral Finland, accessible to both parties, he organized informal workshops that crucially sped the development of laser cooling. The importance of these meetings is highlighted in Bill Phillips' Nobel lecture in 1997 [6]. However, as the emphasis in laser cooling moved from a semiclassical description to quantum theory, Stig started to look for new avenues of research. My contact with Stig came when I went to see him for an MSc thesis topic. This involved polarization spectroscopy and modelling of an experiment performed by the laser spectroscopy group (Birger Ståhlberg) at the University of Helsinki. Without knowing anything about quantum optics I then found myself immediately in one of the Finnish-Soviet workshops on quantum electronics in the small town of Porvoo slightly east of Helsinki. There I met people like Juha Javanainen, Peter Knight, Axel Schenzle and Vladimir Chebotayev, and my own career in quantum optics began, working on the mathematics of the Landau-Zener model and how to apply it and other such models in molecular excitation by femtosecond pulses for my PhD thesis. This work was done together with Barry Garraway, who was a postdoc in Helsinki in the early 1990s. The Finnish-Soviet meetings continued for a while, and in 1990 we even got to travel to Novosibirsk (and back, too). During its existence (1964-1996), the Research Institute of Theoretical Physics (TFT) had a tremendous impact on physics in Finland. Short and long stays by visitors provided a unique and high-level environment for local researchers, the research fields covered a wide range of physics, and for many Finns returning from abroad it provided a place to stay until something more permanent turned up. Thus many researchers who later became professors had, at some point in their career, a connection with TFT. As a director Stig was very broad-minded and without this the happy atmosphere of TFT could not have existed. In the 1980s young researchers such as Marc-Andre Dupertuis and Steve Barnett worked with Stig at TFT, and in the 1990s it was the turn of Barry Garraway, Ilkka Tittonen and Nikolay Vitanov among others. For his work in 1992-1997 Stig Stenholm received the prestigious Academy of Finland Professorship which provided him with valuable research funds. My graduation in 1992 was followed by Mackillo Kira in 1995 and Päivi Törmä in 1996. Following developments in the field, in the mid-1990s Stig started to work on Bose-Einstein condensation and quantum information. Later he had a Humboldt fellowship, with stays in Germany shared by the Universities at Konstanz (Jürgen Mlynek) and Ulm (Wolfgang Schleich). Unfortunately, the University of Helsinki decided to replace TFT and a corresponding experimental particle physics institute with a new institute, which was mostly seen as the Finnish front-end for CERN collaboration; in 1997 the Helsinki Institute of Physics (HIP) was started. Although the activities of TFT still existed in the theory section of HIP, many things and especially the atmosphere were changed and in 1997 this partly led Stig to accept a position at the Royal Institute of Technology in Stockholm, Sweden, where two of his Finnish students, Patrik Öhberg and Erika Andersson graduated shortly after the move. I moved to HIP at the time, but left for a position in Turku in 2000, and the quantum optics project was finally switched off at HIP in 2003—only later it was found that quantum optics had provided the Institute with its most cited papers, propelling it into the top 5 percent most cited institutes in its field (especially thanks to Norbert Lütkenhaus and his work on quantum cryptography). The time in Stockholm was fruitful for Stig scientifically, but he also became a member of the Royal Swedish Academy of Sciences, and although Nobel committee papers remain secret for 50 years, it is likely that he had a hand in its activities. In 2005 we jointly published a textbook on quantum information [7] and in Stockholm he had, again, very successful postdocs such as Ulf Leonhardt. Finally, in 2005, Stig Stenholm retired, although he is still active, writing papers, taking part in conferences and making research visits. We honoured his 70th birthday at the CEWQO2009 conference, and hope that the future provides us with further opportunities for such events. Looking at the obituary of Dirk ter Haar, I see that his style with students reminds me of Stig's approach. In my opinion, Stig expects independence and initiative from a student, giving perhaps a broad topic in which the student is expected to find his or her own way, whilst working perhaps with a postdoc. Juha Javanainen has talked about the 'sink or swim' style (not referring to Stig, though). There is a famous series of children's books about Moomin trolls by Tove Jansson (another Swedish-speaking Finn like Stig). In one of them, the Moomin find in early spring a small flower in a patch of land uncovered by snow, pushing its way up. One of them wants to cover it against frost during the night, but another says 'Don't, it'll fare better later if it has some difficulties at first'. At CEWQO2009 Stig gave the full list of his finished PhD students: Rainer Salomaa (1973), Temba Dlodlo (1980), Juha Javanainen (1980), Markus Lindberg (1985), Matti Kaivola (1985), Birger Ståhlberg (1985), Kalle-Antti Suominen (1992), Mackillo Kira (1995), Päivi Törmä (1996), Asta Paloviita (1997), Patrik Öhberg (1998), Martti Havukainen (1999), Erika Andersson (2000), Pawel Piwnicki (2001), Åsa Larson (2001), Markku Jääskeläinen (2003), and Jonas Larson (2005). One should also mention Erkki Kyrölä, who eventually graduated at Rochester and Olli Serimaa, who never graduated but published some important early-stage laser cooling work. As a final note I must mention a passion that Stig and I share, namely books. I have nearly 400 professional physics and mathematics books, but I am certain that the size of Stig's library exceeds this by far. And this passion is not solely limited to professional books, as one can see, for example, from the references in Stig's article for these proceedings. His interests cover philosophy, history, science fiction and many other topics, and more importantly, the books in his library also get read. In modern times of narrow specialization, high efficiency and h-index, his approach to science and culture sets an example that is worth following. References [1] Stenholm S and ter Haar D 1968 Dilute mixtures of 3He in superfluid 4He Physica 38 133 [2] Stenholm S and Lamb W E 1969 Semiclassical theory of a high-intensity laser Phys. Rev. 181 618 [3] Stenholm S 1984 The Foundations of Laser Spectroscopy (New York: Wiley) [4] Stenholm S 1986 The semiclassical theory of laser cooling Rev. Mod. Phys. 58 699 [5] Stenholm S 1998 Physics that matters Arkhimedes 42 197 [6] Phillips W D 1990 Nobel lecture: laser cooling and trapping of neutral atoms Rev. Mod. Phys. 70 721 [7] Stenholm S and Suominen K-A 2005 Quantum Approach to Informatics (New York: Wiley)

The Moon

NASA Astrophysics Data System (ADS)

Warren, P. H.

2003-12-01

Oxygen isotopic data suggest that there is a genetic relationship between the constituent matter of the Moon and Earth (Wiechert et al., 2001). Yet lunar materials are obviously different from those of the Earth. The Moon has no hydrosphere, virtually no atmosphere, and compared to the Earth, lunar materials uniformly show strong depletions of even mildly volatile constituents such as potassium, in addition to N2, O2, and H2O (e.g., Wolf and Anders, 1980). Oxygen fugacity is uniformly very low ( BVSP, 1981) and even the earliest lunar magmas seem to have been virtually anhydrous. These features have direct and far-reaching implications for mineralogical and geochemical processes. Basically, they imply that mineralogical diversity and thus variety of geochemical processes are subdued; a factor that to some extent offsets the comparative dearth of available data for lunar geochemistry.The Moon's gross physical characteristics play an important role in the more limited range of selenochemical compared to terrestrial geochemical processes. Although exceptionally large (radius=1,738 km) in relation to its parent planet, the Moon is only 0.012 times as massive as Earth. By terrestrial standards, pressures inside the Moon are feeble: the upper mantle gradient is 0.005 GPa km -1 (versus 0.033 GPa km -1 in Earth) and the central pressure is slightly less than 5 GPa. However, lunar interior pressures are sufficient to profoundly influence igneous processes (e.g., Warren and Wasson, 1979b; Longhi, 1992, 2002), and in this sense the Moon more resembles a planet than an asteroid.Another direct consequence of the Moon's comparatively small size was early, rapid decay of its internal heat engine. But the Moon's thermal disadvantage has resulted in one great advantage for planetology. Lunar surface terrains, and many of the rock samples acquired from them, retain for the most part characteristics acquired during the first few hundred million years of solar system existence. The Moon can thus provide crucial insight into the early development of the Earth, where the direct record of early evolution was effectively destroyed by billions of years of geological activity. Lunar samples show that the vast majority of the craters that pervade the Moon's surface are at least 3.9 Gyr old (Dalrymple and Ryder, 1996). Impact cratering has been a key influence on the geochemical evolution of the Moon, and especially the shallow Moon.The uppermost few meters of the lunar crust, from which all lunar samples are derived, is a layer of loose, highly porous, fine impact-generated debris - regolith or lunar "soil." Processes peculiar to the surface of an atmosphereless body, i.e., effects of exposure to solar wind, cosmic rays, and micrometeorite bombardment, plus spheroidal glasses formed by in-flight quenching of pyroclastic or impact-generated melt splashes, all are evident in any reasonably large sample of lunar soil (Lindsay, 1992; Keller and McKay, 1997; Eugster et al., 2000). The lunar regolith is conventionally envisaged as having a well-defined lower boundary, typically 5-10 m below the surface ( McKay et al., 1991); below the regolith is either (basically) intact rock, or else a somewhat vaguely defined "megaregolith" of loose but not so finely ground material. Ancient highland terrains tend to have a regolith roughly 2-3 times than that of the maria ( Taylor, 1982). However, in much of the highlands the regolith/megaregolith "boundary" may be gradational. The growth of a regolith can approach a steady-state thickness by shielding its substrate against further impacts ( Quaide and Oberbeck, 1975), but there is no reason to believe that the size-frequency spectrum of impactors bombarding the Moon ( Melosh, 1989; Neukum et al., 2001) features a discontinuity at whatever size (of order 1-10 m) would be necessary to limit disintegration to ˜10 m.All lunar samples are from the regolith, so the detailed provenance of any individual lunar sample is rarely obvious; and for ancient highland samples, never obvious. The closest approach toin situ sampling of bedrock came on the Apollo 15 mission. The regolith is very thin near the edge of the Hadley Rille, and many samples of clearly comagmatic basalts were acquired within meters of their 3.3 Ga "young," nearly intact, lava flow, so that their collective provenance is certain (Ryder and Cox, 1996). Even the regional provenance of any individual lunar sample is potentially allocthonous. However, most lunar rocks, even ancient highland rocks, are found within a few hundred kilometers of their original locations. This conclusion stems from theoretical modeling of cratered landscapes ( Shoemaker et al., 1970; Melosh, 1989), plus observational evidence such as the sharpness of geochemical boundaries between lava-flooded maria and adjacent highlands (e.g., Li and Mustard, 2000).Besides breaking up rock into loose debris, impacts create melt. Traces of melt along grain boundaries may suffice to produce new rock out of formerly loose debris; the resultant rock would be classified as either regolith breccia or fragmental breccia, depending upon whether surface fines were important, or not, respectively, in the precursor matter (Stöffler et al., 1980). Features diagnostic of a surface component include the presence of glass spherules (typically a mix of endogenous mare-pyroclastic glasses and impact-splash glasses) or abundant solar-wind-implanted noble gases (e.g., Eugster et al., 2000).Elsewhere, especially in the largest events in which a planet's gravitational strength limits displacement and the kinetic energy of impact is mainly partitioned into heat (Melosh, 1989), impact melt may constitute a major fraction of the volume of the material that becomes new rock. Rocks formed in this manner are classified as impact-melt breccias and subclassified based on whether they are clast-poor or clast-rich, and whether their matrix is crystalline or glassy ( Stöffler et al., 1980). Obvious lithic and mineral clasts are very common in impact-melt breccias, although the full initial proportion of clasts may not be evident in the final breccia. Some of the clasts may be so pulverized, especially in large impact events ( Schultz and Mendell, 1978), that they are "lost" by digestion into comingled superheated impact melt ( Simonds et al., 1976). By some definitions, the term impact-melt breccia may be applied to products of melt plus clast mixtures with initial melt proportion as low as 10 wt.% ( Simonds et al., 1976; Papike et al., 1998).A few impactites feature a recrystallized texture, i.e., they consist dominantly of a mosaic of grains meeting at ˜120° triple junctions. These metamorphic rocks, termed granulitic breccias, may form from various precursor igneous or impactite rocks, and the heat source may be regional (burial) or local, such as a nearby impact melt (Stöffler et al., 1980). But lunar granulitic breccias are almost invariably fine grained, and they tend to be "contaminated" with meteoritic siderophile elements (e.g., M. M. Lindstrom and D. J. Lindstrom, 1986; Warren et al., 1991; Cushing et al., 1999), implying that the precursor rocks were probably mostly shallow impact breccias (brecciation and siderophile-element contamination being concentrated near the surface), and the heat source was probably most often a proximal mass of impact melt.Besides impactites, which are predominant near the bombarded surface, virtually all other lunar crustal rocks are igneous or annealed-igneous. The super-arid Moon has never produced (by any conventional definition) sedimentary rock, and most assuredly has never hosted life. Even metamorphism is of reduced scope, with scant potential for fluid-driven metasomatism. Evidence for metamorphism among returned lunar samples is mostly confined to impact shock and thermal effects. Although regional burial metamorphism may occur (Stewart, 1975), deeply buried materials seldom find their way into the surface regolith, whence all samples come. Annealing of lunar rocks is more likely a product of simple postigneous slow cooling (at significant original depth), dry baking in proximity to an intrusion, or baking within a zone of impact heating.The Moon's repertoire of geochemical processes may seem limited, but it represents a key link between the sampled asteroids (see Chapters 1.05 and 1.11) and the terrestrial planets. Four billion years ago, at a time when all but monocrystalline bits of Earth's dynamic crust were fated for destruction, most of the Moon's crust had already achieved its final configuration. The Moon thus represents a unique window into the early thermal and geochemical state of a moderately large object that underwent igneous differentiation in the inner solar system, and into the cratering history of near-Earth space.

EDITORIAL: Special issue on optical neural engineering: advances in optical stimulation technology Special issue on optical neural engineering: advances in optical stimulation technology

NASA Astrophysics Data System (ADS)

Shoham, Shy; Deisseroth, Karl

2010-08-01

Neural engineering, itself an 'emerging interdisciplinary research area' [1] has undergone a sea change over the past few years with the emergence of exciting new optical technologies for monitoring, stimulating, inhibiting and, more generally, modulating neural activity. To a large extent, this change is driven by the realization of the promise and complementary strengths that emerging photo-stimulation tools offer to add to the neural engineer's toolbox, which has been almost exclusively based on electrical stimulation technologies. Notably, photo-stimulation is non-contact, can in some cases be genetically targeted to specific cell populations, can achieve high spatial specificity (cellular or even sub-cellular) in two or three dimensions, and opens up the possibility of large-scale spatial-temporal patterned stimulation. It also offers a seamless solution to the problem of cross-talk generated by simultaneous electrical stimulation and recording. As in other biomedical optics phenomena [2], photo-stimulation includes multiple possible modes of interaction between light and the target neurons, including a variety of photo-physical and photo-bio-chemical effects with various intrinsic components or exogenous 'sensitizers' which can be loaded into the tissue or genetically expressed. Early isolated reports of neural excitation with light date back to the late 19th century [3] and to Arvanitaki and Chalazonitis' work five decades ago [4]; however, the mechanism by which these and other direct photo-stimulation, inhibition and modulation events [5-7] took place is yet unclear, as is their short- and long-term safety profile. Photo-chemical photolysis of covalently 'caged' neurotransmitters [8, 9] has been widely used in cellular neuroscience research for three decades, including for exciting or inhibiting neural activity, and for mapping neural circuits. Technological developments now allow neurotransmitters to be uncaged with exquisite spatial specificity (down to a single spine, with two-photon uncaging) and in rapid, flexible spatial-temporal patterns [10-14]. Nevertheless, current technology generally requires damaging doses of UV or violet illumination and the continuous re-introduction of the caged compound, which, despite interest, makes for a difficult transition beyond in vitro preparations. Thus, the tremendous progress in the in vivo application of photo-stimulation tools over the past five years has been largely facilitated by two 'exciting' new photo-stimulation technologies: photo-biological stimulation of a rapidly increasing arsenal of light-sensitive ion channels and pumps ('optogenetic' probes[15-18]) and direct photo-thermal stimulation of neural tissue with an IR laser [19-21]. The Journal of Neural Engineering has dedicated a special section in this issue to highlight advances in optical stimulation technology, which includes original peer-reviewed contributions dealing with the design of modern optical systems for spatial-temporal control of optical excitation patterns and with the biophysics of neural-thermal interaction mediated by electromagnetic waves. The paper by Nikolenko, Peterka and Yuste [22] presents a compact design of a microscope-photo-stimulator based on a transmissive phase-modulating spatial-light modulator (SLM). Computer-generated holographic photo-stimulation using SLMs [12-14, 23] allows the efficient parallel projection of intense sparse patterns of light, and the welcome development of compact, user-friendly systems will likely reduce the barrier to its widespread adoption. The paper by Losavio et al [24] presents the design and functional characteristics of their acousto-optical deflector (AOD) systems for studying spatial-temporal dendritic integration in single neurons in vitro. Both single-photon (UV) and two-photon (femtosecond pulsed IR) AOD uncaging systems are described in detail. The paper presents an excellent overview of the current state of the art and limitations of this technology, which is increasingly being applied for both photo- stimulation and imaging [25, 26]. Finally, the paper by Pikov et al [27] studies the modulatory biophysical effects exerted by low power millimeter waves on neuronal excitability and membrane properties of cortical pyramidal neurons in vitro. These extensive neuro-modulatory effects seem to include a thermal component (related to the photo-thermal effects observed under laser illumination [28]) as well as a more specific effect exerted by these lower frequency (sub-THz) electromagnetic waves. These new contributions augment five previous manuscripts published by the journal on optical stimulation technology, which reported the development of a fiber-based system for in vivo optogenetic cortical stimulation [29], patterned stimulation systems based on computer-generated holography [23] and on arrays of micro-LEDs [30] designed for an optical retina neuroprosthetic [31], and an integrated system for optical stimulation with microelectrode array recording [32]. Without doubt, many more will quickly follow as neural engineers and neuroscientists increasingly tackle the many challenges that this exciting area poses. We can all expect to hear much more in the near future about the biophysics and implementation of photo-physical neural-interaction mechanisms, the design of new optogenetic probes and patterned-stimulation systems (including stand-alone and implantable systems), further integration of electrodes and optical components into electro-optical neurostimulation systems, and rapid progress towards multiple medical applications for alleviating neurological disabilities and improving human health. References [1] Durand D M 2006 What is neural engineering? J. Neural Eng. 4 (4) [2] Niemz M H 2007 Laser-Tissue Interactions: Fundamentals and Applications 3rd edn (Berlin: Springer) [3] Arsonval A D 1891 La fibre musculaire est directement excitable par la lumiere C. R. Soc. Biol. 43 318-20 [4] Arvanitaki A and Chalazonitis N 1961 Excitatiory and inhibitory processes initiated by light and infra-red radiations in single identifiable nerve cells Nervous Inhibition ed. E Florey (New York: Pergamon) pP 194-231 [5] Fork R L 1971 Laser stimulation of nerve cells in Aplysia Science 171 907-8 [6] Allegre G, Avrillier S and Albe-Fessard D 1994 Stimulation in the rat of a nerve fiber bundle by a short UV pulse from an excimer laser Neurosci. Lett. 180 261-4 [7] Hirase H, Nikolenko V, Goldberg J H and Yuste R 2002 Multiphoton stimulation of neurons J. Neurobiol. 51 237-47 [8] Callaway E M and Yuste R 2002 Stimulating neurons with light Curr. Opin. Neurobiol. 12 587-92 [9] Ellis-Davies G C 2007 Caged compounds: photorelease technology for control of cellular chemistry and physiology Nat. Methods 4 619-28 [10] Shoham S, O'Connor D H, Sarkisov D V and Wang S S 2005 Rapid neurotransmitter uncaging in spatially defined patterns Nat. Methods 2 837-43 [11] Nikolenko V, Poskanzer K E and Yuste R 2007 Two-photon photostimulation and imaging of neural circuits Nat. Methods 4 943-50 [12] Lutz C, Otis T S, DeSars V, Charpak S, DiGregorio D A and Emiliani V 2008 Holographic photolysis of caged neurotransmitters Nat. Methods 5 821-7 [13] Nikolenko V, Watson B O, Araya R, Woodruff A, Peterka D S and Yuste R 2008 SLM microscopy: scanless two-photon imaging and photostimulation with spatial light modulators Front. Neural Circuits 2 5 [14] Zahid M, Velez-Fort M, Papagiakoumou E, Ventalon C, Angulo M C and Emiliani V Holographic photolysis for multiple cell stimulation in mouse hippocampal slices PLoS One 5 e9431 [15] Boyden E S, Zhang F, Bamberg E, Nagel G and Deisseroth K 2005 Millisecond-timescale, genetically targeted optical control of neural activity Nat. Neurosci. 8 1263-8 [16] Zhang F, Aravanis A M, Adamantidis A, de Lecea L and Deisseroth K 2007 Circuit-breakers: optical technologies for probing neural signals and systems Nat. Rev. Neurosci. 8 577-81 [17] Gradinaru V, Zhang F, Ramakrishnan C, Mattis J, Prakash R, Diester I, Goshen I, Thompson K R, Deisseroth K 2010 Molecular and cellular approaches for diversifying and extending optogenetics Cell 141 154-65 [18] Zhang F, Gradinaru V, Adamantidis A R, Durand R, Airan R D, de Lecea L and Deisseroth K 2010 Optogenetic interrogation of neural circuits: technology for probing mammalian brain structures Nat. Protoc. 5 439-56 [19] Wells J, Kao C, Mariappan K, Albea J, Duco Jansen E, Konrad P and Mahadevan-Jansen A 2005 Optical stimulation of neural tissue in vivo Opt. Lett. 30 504-6 [20] Izzo A D, Richter C P, Jansen E D and Walsh J T Jr 2006 Laser stimulation of the auditory nerve Lasers Surg. Med. 38 745-53 [21] Richter C P, Izzo A D, Wells J, Jansen E D and Walsh J T Jr 2010 Neural stimulation with optical radiation Laser Photonics Rev. available at doi:10.1002/lpor.200900044 [22] Nikolenko V, Peterka D S and Yuste R 2010 A portable laser photostimulation and imaging microscope J. Neural Eng. 7 045001 [23] Golan L, Reutsky I, Farah N and Shoham S 2009 Design and characteristics of holographic neural photo-stimulation systems J. Neural Eng. 6 066004 [24] Losavio B E, Iyer V, Patel S and Saggau P 2010 Acousto-optical laser scanning for multi-site photo-stimulation of single neurons in vitro J. Neural Eng. 7 045002 [25] Duemani Reddy G, Kelleher K, Fink R and Saggau P 2008 Three-dimensional random access multiphoton microscopy for functional imaging of neuronal activity Nat. Neurosci. 11 713-20 [26] Grewe B F, Langer D, Kasper H, Kampa B M and Helmchen F 2010 High-speed in vivo calcium imaging reveals neuronal network activity with near-millisecond precision Nat. Methods 7 399-405 [27] Pikov V, Arakaki X, Harrington M, Fraser S E and Siegel P H 2010 Modulation of neuronal activity and plasma membrane propertiess with low-power millimeter waves in organotypic cortical slices J. Neural Eng. 7 045003 [28] Liang S et al 2009 Temperature-dependent activation of neurons by continuous near-infrared laser Cell Biochem. Biophys. 53 33-42 [29] Aravanis A M, Wang L-P, ZhangF, Meltzer L A, Mogri M Z, Schneider M B and Deisseroth K 2007 An optical neural interface: in vivo control of rodent motor cortex with integrated fiberoptic and optogenetic technology J. Neural Eng. 4 S143-56 [30] Grossman N et al 2010 Multi-site optical excitation using ChR2 and micro-LED array J. Neural Eng. 7 016004 [31] Degenaar P, Grossman N, Memon M A, Burrone J, Dawson M, Drakakis E, Neil M and Nikolic K 2009 Optobionic vision—a new genetically enhanced light on retinal prosthesis J. Neural Eng. 6 035007 [32] Zhang J et al 2009 Integrated device for optical stimulation and spatiotemporal electrical recording of neural activity in light-sensitized brain tissue J. Neural Eng. 6 055007

New Observations of Comet Hale-Bopp from La Silla

NASA Astrophysics Data System (ADS)

1998-10-01

Methanol and Hydrogen Cyanide Detected at Record Distance Observations of famous Comet Hale-Bopp continue with the 15-m Swedish-ESO Submillimetre Telescope (SEST) at the La Silla Observatory. They show amazingly strong activity of this unusual object, also at the present, very large distance from the Sun. The radio observations document in detail the release of various molecules from the comet's icy nucleus. Of particular interest is the observed emission from methanol ( CH 3 OH ) and hydrogen cyanide ( HCN ) molecules, never before detected in any comet this far away. Comet Hale-Bopp still going strong Just over 18 months after its perihelion passage on April 1, 1997, Comet Hale-Bopp (official designation C/1995 O1 ) is continuing its outward journey through the Solar System. It is now about 1,000 million kilometres (6.7 AU) from the Sun and the Earth, i.e. almost at the same distance as when it was first discovered in July 1995. After having traversed the northern sky in 1996 and 1997, the comet passed the celestial equator in late June 1997 and is now seen in the southern constellation Volans (The Flying Fish), i.e. just east of the Large Magellanic Cloud. It can only be observed from southern latitudes. The comet's brightness has decreased by a factor of more than 10,000 since it was at its brightest in March 1997, just before perihelion. However, the magnitude is still around 9 - 10, or only about 20-40 times fainter than what can be seen with the unaided eye. Hale-Bopp is therefore visible in binoculars to southern observers as a fuzzy object with a diameter of a few arcminutes. New observations from La Silla Several telescopes at La Silla are following the evolution of the activity of Comet Hale-Bopp as it recedes from the Sun. In particular, the comet is observed monthly with SEST , a 15-m diameter submillimetre telescope operated jointly by the Onsala Space Observatory (OSO, Chalmers University of Technology, Gothenburg, Sweden) and ESO; it is the only telescope of its type in the southern hemisphere. Alternating each month, a Swedish team (headed by Anders Winnberg , OSO) and a European team (headed by Dominique Bockelée-Morvan , Observatoire de Paris) observe emission lines in the radio region of the spectrum from some of the molecules in the comet's coma (the cloud of gas and dust around the cometary "dirty-snowball" nucleus). These data are of great importance for understanding the mechanisms that are responsible for the outgassing (sublimation) of ices inside the nucleus of Comet Hale-Bopp. The observations began at SEST in September 1997 and constitute a follow-up programme of a long-term monitoring project at radio wavelengths that was started in August 1995 at the telescopes of the Institut de RadioAstronomie Millimétrique (IRAM) , the James Clerk Maxwell Telescope (JCMT) , the Caltech Submillimeter Observatory (CSO) and the Nançay radio telescope by several teams of astronomers in Europe and US [1]. Radio emission from nine molecules in the coma were studied: H 2 O (water; by means of observations of the radical OH ), CO (carbon monoxide), CH 3 OH (methanol), H 2 CO (formaldehyde), HCN (hydrogen cyanide), HNC (isomeric hydrogen cyanide), CH 3 CN (methyl cyanide), H 2 S (hydrogen sulphide) and CS (carbon sulphide). Detection of methanol and hydrogen cyanide at record distance ESO PR Photo 40a/98 ESO PR Photo 40a/98 [Preview - JPEG: 800 x 911 pix - 264k] [High-Res - JPEG: 3000 x 3415 pix - 1.6Mb] PR Photo 40a/98 displays a part of the radio spectrum with emission from CH 3 OH molecules in the coma of Comet Hale-Bopp, as observed with the 15-m SEST telescope at La Silla from August 16 to 19, 1998. Three lines of this molecule were detected at 145.0938, 145.0974 and 145.1032 GHz, respectively. The total integration (exposure) time is 708 min. The intensity is indicated in units of antenna temperature. Observations at SEST were performed in July and August 1998 by Emmanuel Lellouch (Observatoire de Paris) and Marcus Gunnarsson (Uppsala Astronomiska Observatorium, Sweden), respectively. Three molecules were still detected : carbon monoxide ( CO ) at 230 GHz, hydrogen cyanide ( HCN ) at 89 GHz and methanol ( CH 3 OH ) at 145 GHz. On August 11, when Hale-Bopp was just over 900 million km (6 AU) from the Sun, no less than 2.4 · 10 28 CO molecules were released by the comet per second, corresponding to 1100 kg per second. The measured production rates of HCN and CH 3 OH were about 200 and 20 times smaller, respectively. The observations of these two organic species at SEST constitute the most distant detections ever made in any comet. The sublimation of water, the main constituent of cometary ices, is responsible for cometary activity within 3-4 AU from the Sun. However, at larger distances, this process ceases, due to the low temperature of the nucleus. At the present large distance from the Sun, the CO molecule is now the prime source of activity of Hale-Bopp. When Comet Hale-Bopp was approaching the Sun before perihelion passage in 1997, the long-term monitoring programmes - in the radio wavelength region as well as in other spectral domains - clearly showed the transition from a CO - to a water-dominated coma, at about the time the comet came within 3-4 AU from the Sun. The CO -production rate now measured at SEST at 6 AU on the outward leg is about 100 times less than that at perihelion, and close to the value measured at the same distance from the Sun before perihelion. While CO was first detected in Hale-Bopp in September 1995 at 6.8 AU from the Sun, only a few weeks after the discovery, HCN and CH 3 OH were not detected until a few months later, when the comet had approached to within 4.8-4.9 AU. It is likely that the convincing detection of these two molecules in August 1998 (cf., e.g., PR Photo 40a/98 ) benefitted from an outburst (a sudden release of material from the nucleus) on August 15-19. Some other species were observed at SEST out to a distance of 3-4 AU ( H 2 S, CS, H 2 CO ), but they are no longer easily detectable due to low production rates and the SEST sensitivity limit. New data may provide a "look into the nucleus" ESO PR Photo 40b/98 ESO PR Photo 40b/98 [Preview - JPEG: 800 x 1062 pix - 357k] [High-Res - JPEG: 3000 x 3981 pix - 2.1Mb] PR Photo 40b/98 displays Hale-Bopp gas production curves (quantity of released gas as a function of heliocentric distance) from radio observations at the IRAM, JCMT, CSO, SEST and Nançay telescopes. Pre-perihelion data are shown on the left, post-perihelion data on the right. Adapted from a figure prepared by Nicolas Biver [2]. Comet Hale-Bopp provided the first opportunity in modern times to follow the activity of a comet over a very large range of heliocentric distances, cf. PR Photo 40b/98 . The new data trace the gas release in some detail as the temperature and insolation change when the comet moves along its orbit. They show similarities and differences between individual molecules that in turn contain useful information about the physical state of cometary ices in the nucleus and its internal structure. Some of the current key questions in this research field are concerned with the degree of separation of different ices ("chemical differentiation") in the upper layers of the nucleus, the form under which these ices co-exist and, not least, the still not understood production mechanisms at large heliocentric distances. These new observations will provide very valuable support to the theoretical studies of the cometary nucleus, now being undertaken by several research groups around the world. The new observations of molecular lines in the radio spectral region also provide information about the temperature in the coma, if several lines of the same species are observed. Moreover, they serve to measure the expansion velocity of the gas and the outgassing pattern of the nucleus. For instance, the observations of CH 3 OH in August 1998 show that the coma is now very cold at about 16 K (-257 o C). At perihelion (0.9 AU from the Sun), the corresponding temperature was of the order of 110 K (-163 o C). The expansion velocity has also considerably decreased since perihelion, from 1.1 km/sec to 0.5 km/sec. There is also evidence of anisotropic outgassing : more gas is seen to be flowing out from the sunlit hemisphere of the nucleus. Observations continue The monitoring of Comet Hale-Bopp at the SEST telescope will continue, at least until March 1999. The comet will then be nearly 1,200 million km (7.9 AU) from the Sun. ESO PR Photo 40c/98 ESO PR Photo 40c/98 [Preview - JPEG: 800 x 933 pix - 432k] [High-Res - JPEG: 3000 x 3498 pix - 2.5Mb] PR Photo 40c/98 shows Comet Hale-Bopp, as imaged on October 19, 1998, in visible light and with the DFOSC instrument at the Danish 1.5-m telescope on La Silla. At this time, the comet was about 1,000 million kilometer (6.7 AU) from the Earth and the Sun. Although well beyond Jupiter's orbit, it is very obvious that strong nucleus activity is still present - the large coma extends well beyond the field of view (200 x 200 arcsec or about 1 million km at the distance of the comet). The image mostly depicts cometary dust that reflects the sunlight. The coma is very asymmetric with more material in the northern hemisphere (above). There are also some jets embedded in the coma which indicate that some of the dust is emitted from active regions on the surface of the nucleus. The background stars are slightly elongated since the telescope followed the motion of the comet in the sky during the exposure. Technical information : 5-min exposure through a broadband V-filtre. North is up, East is left. Observers: Kirsten Kraiberg Knudsen (Copenhagen University, Denmark) and Hermann Boehnhardt (ESO/Chile) Observations are also made from time to time with other telescopes at La Silla. As an example, Photo 40c/98 was obtained a few days ago with the Danish 1.5-m telescope. It shows that a very complex coma structure is still present. Due to the large size of the nucleus, probably 40 - 60 km in diameter, it will be possible to observe this comet with large optical telescopes for many years to come. Information about Hale-Bopp on the web Additional information about Comet Hale-Bopp is available on the web at many sites. Some of the most comprehensive websites may be accessed via the ESO Hale-Bopp site. Notes: [1] Other scientists involved in the long-term radio monitoring of Comet Hale-Bopp are Nicolas Biver (Institute for Astronomy, University of Hawaii, USA), Pierre Colom, Jacques Crovisier, Eric Gérard, Benoit Germain, Emmanuel Lellouch (Observatoire de Paris, France), Didier Despois (Observatoire de Bordeaux, France), Gabriel Paubert (IRAM, Granada, Spain), Raphael Moreno, Joern E. Wink (IRAM, Grenoble, France), John K. Davies (JAC, Hawaii, USA), William R.F. Dent (Royal Observatory, Edinburgh, UK), Hans Rickman, Marcus Gunnarsson (Uppsala Astronomiska Observatorium, Sweden), Per Bergman, Lars E.B. Johansson (OSO, Sweden), Fredrik Rantakyroe (SEST, La Silla), Darek C. Lis, David Mehringer, Dominic Benford, Martin Gardner, Tom G. Phillips (CSO, USA), Heike Rauer (DLR, Berlin, Germany). [2] The figure appears in N. Biver et al. : "Long-term Monitoring of the Outgassing of C/1995 O1 (Hale-Bopp) at Radio Wavelengths", a poster paper presented at the DPS meeting on October 11-16, 1998 (Madison, Wisconsin, USA) and to be published in Vol. 30 of the Bulletin of the American Astronomical Society . How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: http://www.eso.org ). ESO Press Photos may be reproduced, if credit is given to the European Southern Observatory.

Disappearance of the last lions and hyenas of Europe in the Late Quaternary - a chain reaction of large mammal prey migration, extinction and human antagonism

NASA Astrophysics Data System (ADS)

Diedrich, Cajus G.

2010-05-01

In the Eemian to Early/Middle Weichselian (Late Pleistocene), when the Scandinavian and Alpine Glaciers were still small, and northern Germany under mammoth steppe to taiga palaoenvironment conditions, Late Quaternary steppe lions were well distributed in northern to central Germany, whereas generally all over Central Europe bones and rarely articulated skeletons were found less at open air but mainly at cave sites (Diedrich 2007a, 2008a-b, 2009a-b, 2010a-c, k, in review a-b; Diedrich and Rathgeber in review). A similar distribution, but more dense, is reported for the Late Quaternary Ice Age spotted hyenas (Diedrich 2005, 2006, 2007b-c, 2008a, c, 2010f-j, in review c-d, Diedrich and Žák 2006). The last lions of northern Europe were thought to have reached into the final Magdalénan (cf. Musil 1980). This can be not concluded with a restudy of the bone material from the Late Magdalenian (V-VI) Teufelsbrücke stone arch site near Saalfeld (Thuringia, Central Germany) and many other Magdalenian stations (open air and caves) in northern to central Germany (Münsterland Bay, Sauerland Karst, Harz Mountain Karst, Thuringian Karst). None of those sites yield remains of final Upper Pleistocene spotted hyenas or steppe lion bones anymore, nor in the few preserved Late Magdalenian mobile art can those be recognized in those regions. The last lion remains seem to reach into the Aurignacian or possibly into the Early Gravettian (early Late Weichselian) documented especially at the cave bear den, hyena den and overlapping Neandertalian to Modern human camp site Balve Cave (Sauerland Karst, cf. archaeology in Günther 1964) where still a mammoth fauna is documented for that time (Diedrich 2010a). The last and by archaeological layers dated hyena remains were also found in the Balve Cave and are from the Late Middle Palaeolithic cave site reaching a maximum Aurignacian age documenting an overlapping of hyena den and human camp site use (Diedrich 2010a, b). In northern Germany there are no records of indirectly dated hyena and lion remains being younger then even Aurignacian/Early Gravettian (35.000-28.000 BP). Those largest Late Quaternary predators must have got extinct in northern Germany with the Late Weichselian/Wuermian extending Skandinavian Glacier, which reached northern Europe between Hamburg and Berlin its maximum extension about 24.000 BP (Skupin et al. 1993). The two largest predators of the Late Quaternary of Europe seem to have been well represented in the Gravettian and up to Magdalénian Late Palaeolithic of southern Europe, in which mainly lions, but only rarely hyenas are well documented within the cave and mobile art (e.g Breuil 1952, Begouen and Clottes 1987, Chauvet et al. 1995, Diedrich and Rathgeber in review, Diedrich 2005). Hyenas and lions must have been represented in the Gravettian, Early and Middle and possibly even ?Late Magdalenian in southern Europe, which must have resulted from a southern migration of those predators during the Late Weichselian/Wuermian together with the megafauna and humans. The disappearance of hyenas and lions also correlate with the extinction of mammoth and woolly rhinoceros in northern Germany. The large mammals such as elephants and rhinoceroses were highly important for hyenas and lions during the Late Quaternary. Hyenas had a systematic scavenging strategy on both large prey which was even "transferred" until today compared to modern spotted hyenas and lions of Africa (Diedrich 2010d, e, in prep). Where those Late Quaternary giant mammals such as woolly mammoth and woolly rhinoceros were absent in middle mountainous regions (e.g. Sauerland Karst, Harz Mountain Karst, Bohemian Karst, Thuringian Karst) those had to kill other medium sized animals such as horse or steppe bison and those in larger amounts (Diedrich 2008, 2010c). Woolly rhinoceros and woolly mammoth seem to be not known in northern Germany after Aurignacian/?Early Gravettian times (Sauerland Karst and Münsterland Bay, Harz Mountain Karst) such as humans (archaeology cf. Günther 1988) but there are also lacking radiocarbon dating series or new excavations. Humans must have been in antagonism to the large predators about their prey and also their Late Palaeolithic sanctuaries - the large caves especially in southern Europe, in which they left thousands of animal figurations mainly during the Gravettian to Late Magdalenian periods (e.g. Breuil 1952, Begouen and Clottes 1987, Chauvet et al. 1995). Therefore the extinction reason of the largest predators of the Late Quaternary seems to be a complex combination of climate change with resulting maximum glacier extension which finally caused a southern directed megafaunal migration and reduction of the available caves and habitat areas in general. Finally in those southern European regions a higher competition about larger caves as cave bear hibernation places, hyena den sites and human settlement/sanctuary sites must have happened. Therefore an active hunt onto lions and hyenas can not be excluded nor be proven well yet, even if there are finds of necklesses in Europe from Late Palaeolithic ages made of mainly carnivore teeth including rare lion and hyena teeth, which might have been only collected. The resettlement of the northern European region by humans and a reduced "reindeer fauna" and its main and largest predators such as wolves and wolverines after the maximum glacier extension in the middle Late Weichselian started not before the Late Magdalenian (Magdalénian V: e.g. Perick Caves, Martins Cave - Sauerland Karst; Rübeland Caves - Harz Mountain Karst, Teufelsbrücke stone arch - Thuringian Karst). Humans occupied at that post-maximum glaciation time many caves in the Sauerland Karst region and even at open air sites in the Münsterland Bay or central Germany (cf. Bosinski 1987, Günther 1988). Within this Late Magdalénian V-VI times in the record of ten thousands of bones from more then 100 sites no hyena or lion remains are recorded anymore in northern and central Germany, such as cave bears. References Begouen R. and Clottes J. 1987. Les Trois Frères after Breuil. Antiquity, 61: 180-187. Bosinski, G. 1987. Die große Zeit der Eiszeitjäger. Europa zwischen 40.000 und 10.000 v.Chr. Jahrbuch des Römisch-Germanischen Zentralmuseums, 34: 13-139. Breuil, H. 1952. Four Hundred Centuries of Cave Art. Montignac, Dordogne, 414 pp. Chauvet, J.-M., Deschamps B.E, and Hillaire C. 1995. Grotte Chauvet. Altsteinzeitliche Höhlenkunst im Tal der Ardèche. Thorbecke Speläo 1, Sigmaringen, 120 pp. Diedrich, C. 2005. Eine oberpleistozäne Population von Crocuta crocuta spelaea (GOLDFUSS 1823) aus dem eiszeitlichen Fleckenhyänenhorst Perick-Höhlen von Hemer (Sauerland, NW Deutschland) und ihr Kannibalismus. Philippia, 12 (2): 93-115, Kassel. Diedrich, C. 2006. The Crocuta crocuta spelaea (Goldfuss 1823) population from the early Upper Pleistocene hyena open air prey deposit site Biedensteg near Bad Wildungen (Hess, NW Germany) and the contribution to their phylogenetic position, coprolites and prey. Cranium, 23 (2): 39-53, Amsterdam. Diedrich, C. 2007a. Upper Pleistocene Panthera leo spelaea (Goldfuss 1810) skeleton remains from Praha-Podbaba and the contribution to other lion finds from loess and river terrace sites in Central Bohemia (Czech Republic). Bulletin of Geosciences, 82 (2), 99-117, Prague. Diedrich, C. 2007b. Crocuta crocuta spelaea (GOLDFUSS 1823) remains from the Upper Pleistocene hyaena Teufelskammer Cave den site near Hochdahl in the Neander valley (NRW, NW Germany). Cranium, 24 (2): 39-44, Amsterdam. Diedrich, C. 2007c. The Upper Pleistocene Crocuta crocuta spelaea (GOLDFUSS 1823) population and its prey from the gypsum karst den site Westeregeln near Magdeburg (Middle Germany). Abhandlungen und Berichte für Naturkunde, 30: 57-83, Magdeburg. Diedrich, C. 2008a. Late Pleistocene Hystrix (Acanthion) brachyura LINNAEUS 1758 from the Fuchsluken cave at the Rote Berg near Saalfeld (Thuringia, Germany) - a porcupine and hyena den and contribution to their palaeobiogeography. - The Open Palaeontological Journal, 2008 (1): 33-41. Diedrich, C. 2008b. The rediscovered holotypes of the Upper Pleistocene spotted hyena Crocuta crocuta spelaea (Goldfuss 1823) and the steppe lion Panthera leo spelaea (Goldfuss, 1810) and taphonomic discussion to the Zoolithen Cave hyena den at Geilenreuth (Bavaria, South-Germany). Zoological Journal of the Linnaean Society London, 154, 822-831. Diedrich, C. 2008c. Late Pleistocene hyenas Crocuta crocuta spelaea (GOLDFUSS 1823) from Upper Rhine valley open air sites and the contribution to skull shape variability. Cranium, 25-2: (in press), Amsterdam. Diedrich, C. 2009a. Upper Pleistocene Panthera leo spelaea (GOLDFUSS 1810) remains from the Bilstein Caves (Sauerland Karst) and contribution to the steppe lion taphonomy, palaeobiology and sexual dimorphism. Annales de Paléontologie, 95 (2009) 117-138, Amsterdam. Diedrich, C. 2009b. Steppe lion remains imported by Ice Age spotted hyenas into the Late Pleistocene Perick Caves hyena den in Northern Germany. Quaternary Research 71 (3): 361-374, Amsterdam. Diedrich, C. 2010a. Pleistocene Panthera leo spelaea (Goldfuss, 1810) remains from the Balve Cave (NW Germany) - a hyena den and Middle Palaeolithic human site. - International Journal of Osteoarchaeology (acepted). Diedrich, C. 2010b. Ein Skelett einer kranken Löwin Panthera leo spelaea (Goldfuss 1810) und andere männliche Löwenreste aus Neumark-Nord. - Archäologie in Sachsen-Anhalt, Sonderbad (accepted). Diedrich, C. 2010c. Late Pleistocene lion Panthera leo spelaea (GOLDFUSS 1810) remains from the Keppler Cave (Sauerland Karst, NW Germany). Cranium 26, Amsterdam (in press). Diedrich, C. 2010c. Specialized horse killers in Europe - foetal horse remains in the Late Pleistocene Srbsko Chlum-Komín Cave hyena den in the Bohemian Karst (Czech Republic) and actualistic comparisons to modern African spotted hyenas as zebra hunters. - Quaternary International. Diedrich, C. 2010d. Mammuthus primigenius (Blumenbach, 1799) carcass destructors, bone collectors, crackers and gnawers of the Late Pleistocene in Central Europe - the Ice Age spotted hyenas and their feeding strategies on their largest prey - the mammoth. Abstract Vth International Conference on Mammoths and their relatives, Le Puy-en-Velay, France. Diedrich, C. 2010e. Späteiszeiliche Fleckenhyänen-Fressstrategien und Steppenlöwen an ihrer größte Beute - dem Waldelefanten Palaeoloxodon antiquus Falconer & Cautley 1845 in Neumark-Nord. Archäologie in Sachsen-Anhalt, Sonderband (accepted). Diedrich, C. 2010f. Die späteiszeitlichen Fleckenhyänen und deren Exkremente aus Neumark-Nord. Archäologie in Sachsen-Anhalt, Sonderband (accepted). Diedrich, C. 2010g. Rare Upper Pleistocene Crocuta crocuta spelaea (GOLDFUSS 1823) remains from northern Czech Republic open air loess sites along the Elbe River. Cranium, (accepted). Diedrich, C. 2010h. Europe's first Upper Pleistocene Crocuta crocuta spelaea (GOLDFUSS 1823) skeleton from a small cannibalistic hyena population found in the main dome of the Koněprusy Caves - a hyena cave prey depot site in the Bohemian Karst (Czech Republic). Acta Palaeontologica Polonica (in review). Diedrich, C. 2010i. Periodical use of the Balve Cave (NW Germany) as a Late Pleistocene Crocuta crocuta spelaea (GOLDFUSS 1823) den - hyena occupations and bone accumulations versa human Middle Palaeolithic activity. Quaternary International. Diedrich, C. 2010j. The Crocuta crocuta spelaea (GOLDFUSS 1823) population from the Late Pleistocene Rösenbeck Cave den in NW Germany and contribution to the sexual dimorphism and palaeobiogeography of the last hyenas of Europe. Annales de Paléontologie. Diedrich, C. 2010k. Upper Pleistocene Panthera leo spelaea (Goldfuss 1810) remains from an open air loess bone accumulation site in Freyburg a. U. (Central Germany). Jahresschrift für mitteldeutsche Vorgeschichte (accepted). Diedrich, C. in prep. Coelodonta antiquitatis (Blumenbach 1799) hunters and scavengers - the Late Pleistocene spotted hyena Crocuta crocuta spelaea (Goldfuss 1823) and its feeding strategy on its most important prey in Europe. Diedrich, C. in review a. A diseased Panthera leo spelaea (Goldfuss, 1810) lioness from a forest elephant graveyard in the Late Pleistocene (Eemian) interglacial lake at Neumark-Nord, Central Germany. Quaternary International. Diedrich, C. in review b. Late Pleistocene steppe lion Panthera leo spelaea (Goldfuss, 1810) remains from the open air hyena den Emscher River terrace site Bottrop and other sites of northern Germany - new proves for hyena-lion antagonism. Palaeogeography, Palaeoclimatology, Palaeoecology. DIEDRICH, C. in review c. The Crocuta crocuta spelaea (GOLDFUSS 1823) population and its prey from the Upper Pleistocene Teufelskammer Cave hyena den site in the Neandertal (NRW, NW Germany). Annales de Paléontologie. Diedrich, C. in review d. The Late Pleistocene Crocuta crocuta spelaea (Goldfuss, 1823) population from the Late Pleistocene hyena open air Emscher River terrace den near Bottrop (NWGermany) and other sites in the Westphalian Bay and its mammoth and woolly rhinoceros prey. Quaternary International. Diedrich, C. and Rathgeber, T. in review. Late Pleistocene steppe lion Panthera leo spelaea (Goldfuss, 1810) skeleton remains of the Upper Rhine valley (SW Germany) and contribution to their palaeobiogeography, sexual dimorphism and palaeoecology. Palaeogeography Palaeoclimatology Palaeoecology. Diedrich, C. AND Žák, K. 2006. Prey deposits and den sites of the Upper Pleistocene hyena Crocuta crocuta spelaea (Goldfuss, 1823) in horizontal and vertical caves of the Bohemian Karst (Czech Republic). Bulletin of Geosciences, 81 (4), 237-276. Günther, K. 1964. Die altsteinzeitlichen Funde der Balve Höhle. Bodenaltertümer Westfalens, 8, 1-165. Günther, K. 1988. Alt- und Mittelsteinzeitliche Fundplätze in Westfalen. Teil 2. Einführung in die Vor- und Frühgeschichte Westfalens 6, 1-183. Musil, R. 1980. Die Großsäoger und Vögel der Teufelsbrücke. In: Feustel, R. Magdalénienstation Teufelsbrücke. II: Paläontologischer Teil. Weimarer Monographien zur Ur- und Frühgeschichte 3, 1-71. Skupin, K., Speetzen, E. and Zandstra, J.G. 1993. Die Eiszeit in Nordwestdeutschland. GLA Nordrhein-Westfalen, Krefeld, 143 pp.

"First Light" for the VLT Interferometer

NASA Astrophysics Data System (ADS)

2001-03-01

Excellent Fringes From Bright Stars Prove VLTI Concept Summary Following the "First Light" for the fourth of the 8.2-m telescopes of the VLT Observatory on Paranal in September 2000, ESO scientists and engineers have just successfully accomplished the next major step of this large project. On March 17, 2001, "First Fringes" were obtained with the VLT Interferometer (VLTI) - this important event corresponds to the "First Light" for an astronomical telescope. At the VLTI, it occurred when the infrared light from the bright star Sirius was captured by two small telescopes and the two beams were successfully combined in the subterranean Interferometric Laboratory to form the typical pattern of dark and bright lines known as " interferometric fringes ". This proves the success of the robust VLTI concept, in particular of the "Delay Line". On the next night, the VLTI was used to perform a scientific measurement of the angular diameter of another comparatively bright star, Alpha Hydrae ( Alphard ); it was found to be 0.00929±0.00017 arcsec . This corresponds to the angular distance between the two headlights of a car as seen from a distance of approx. 35,000 kilometres. The excellent result was obtained during a series of observations, each lasting 2 minutes, and fully confirming the impressive predicted abilities of the VLTI . This first observation with the VLTI is a monumental technological achievement, especially in terms of accuracy and stability . It crucially depends on the proper combination and functioning of a large number of individual opto-mechnical and electronic elements. This includes the test telescopes that capture the starlight, continuous and extremely precise adjustment of the various mirrors that deflect the light beams as well as the automatic positioning and motion of the Delay Line carriages and, not least, the optimal tuning of the VLT INterferometer Commissionning Instrument (VINCI). These initial observations prove the overall concept for the VLTI . It was first envisaged in the early 1980's and has been continuously updated, as new technologies and materials became available during the intervening period. The present series of functional tests will go on for some time and involve many different configurations of the small telescopes and the instrument. It is then expected that the first combination of light beams from two of the VLT 8.2-m telescopes will take place in late 2001 . According to current plans, regular science observations will start from 2002, when the European and international astronomical community will have access to the full interferometric facility and the specially developed VLTI instrumentation now under construction. A wide range of scientific investigations will then become possible, from the search for planets around nearby stars, to the study of energetic processes at the cores of distant galaxies. With its superior angular resolution (image sharpness), the VLT is now beginning to open a new era in observational optical and infrared astronomy. The ambition of ESO is to make this type of observations available to all astronomers, not just the interferometry specialists. Video Clip 03/01 : Various video scenes related to the VLTI and the "First Fringes". PR Photo 10a/01 : "First Fringes" from the VLTI on the computer screen. PR Photo 10b/01 : Celebrating the VLTI "First Fringes" . PR Photo 10c/01 : Overview of the VLT Interferometer . PR Photo 10d/01 : Interferometric observations: Fringes from two stars of different angular size . PR Photo 10e/01 : Interferometric observations: Change of fringes with increasing baseline . PR Photo 10f/01 : Aerial view of the installations for the VLTI on the Paranal platform. PR Photo 10g/01 : Stations for the VLTI Auxiliary Telescopes. PR Photo 10h/01 : A test siderostat in place for observations. PR Photo 10i/01 : A test siderostat ( close-up ). PR Photo 10j/01 : One of the Delay Line carriages in the Interferometric Tunnel. PR Photo 10k/01 : The VINCI instrument in the Interferometric Laboratory. PR Photo 10l/01 : The VLTI Control Room . "First Fringes at the VLTI": A great moment! First light of the VLT Interferometer - PR Video Clip 03/01 [MPEG - x.xMb] ESO PR Video Clip 03/01 "First Light of the VLT Interferometer" (March 2001) (5025 frames/3:21x min) [MPEG Video+Audio; 144x112 pix; 6.9Mb] [MPEG Video+Audio; 320x240 pix; 13.7Mb] [RealMedia; streaming; 34kps] [RealMedia; streaming; 200kps] ESO Video Clip 03/01 provides a quick overview of the various elements of the VLT Interferometer and the important achievement of "First Fringes". The sequence is: General view of the Paranal observing platform. The "stations" for the VLTI Auxiliary Telescopes. Statement by the Manager of the VLT project, Massimo Tarenghi . One of the VLTI test telescopes ("siderostats") is being readied for observations. The Delay Line carriages in the Interferometric Tunnel move. The VINCI instrument in the Interferometric Laboratory is adjusted. Platform at sunset, before the observations. Astronomers and engineers prepare for the first observations in the VLTI Control Room in the Interferometric Building. "Interferometric Fringes" on the computer screen. Concluding statements by Andreas Glindemann , VLTI Project Leader, and Massimo Tarenghi . Distant view of the installations at Paranal at sunset (on March 1, 2001). The moment of "First Fringes" at the VLTI occurred in the evening of March 17, 2001 . The bright star Sirius was observed with two small telescopes ("siderostats"), specially constructed for this purpose during the early VLTI test phases. ESO PR Video Clip 03/01 includes related scenes and is based on a more comprehensive documentation, now available as ESO Video News Reel No. 12. The star was tracked by the two telescopes and the light beams were guided via the Delay Lines in the Interferometric Tunnel to the VINCI instrument [1] at the Interferometric Laboratory. The path lengths were continuously adjusted and it was possible to keep them stable to within 1 wavelength (2.2 µm, or 0.0022 mm) over a period of at least 2 min. Next night, several other stars were observed, enabling the ESO astronomers and engineers in the Control Room to obtain stable fringe patterns more routinely. With the special software developed, they also obtained 'on-line' an accurate measurement of the angular diameter of a star. This means that the VLTI delivered its first valid scientific result, already during this first test . First observation with the VLTI ESO PR Photo 10a/01 ESO PR Photo 10a/01 [Preview - JPEG: 400 x 315 pix - 96k] [Normal - JPEG: 800 x 630 pix - 256k] [Hi-Res - JPEG: 3000 x 2400 pix - 1.7k] ESO PR Photo 10b/01 ESO PR Photo 10b/01 [Preview - JPEG: 400 x 218 pix - 80k] [Normal - JPEG: 800 x 436 pix - 204k] Caption : PR Photo 10a/01 The "first fringes" obtained with the VLTI, as seen on the computer screen during the observation (upper right window). The fringe pattern arises when the light beams from two small telescopes are brought together in the VINCI instrument. The pattern itself contains information about the angular extension of the observed object, here the bright star Sirius . More details about the interpretation of this pattern is given in Appendix A. PR Photo 10b/01 : Celebrating the moment of "First Fringes" at the VLTI. At the VLTI control console (left to right): Pierre Kervella , Vincent Coudé du Foresto , Philippe Gitton , Andreas Glindemann , Massimo Tarenghi , Anders Wallander , Roberto Gilmozzi , Markus Schoeller and Bill Cotton . Bertrand Koehler was also present and took the photo. Technical information about PR Photo 10a/01 is available below. Following careful adjustment of all of the various components of the VLTI, the first attempt to perform a real observation was initiated during the night of March 16-17, 2001. "Fringes" were actually acquired during several seconds, leading to further optimization of the Delay Line optics. The next night, March 17-18, stable fringes were obtained on the bright stars Sirius and Lambda Velorum . The following night, the first scientifically valid results were obtained during a series of observations of six stars. One of these, Alpha Hydrae , was measured twice, with an interval of 15 minutes between the 2-min integrations. The measured diameters were highly consistent, with a mean of 0.00929±0.00017 arcsec. This new VLTI measurement is in full agreement with indirect (photometric) estimates of about 0.009 arcsec. The overall performance of the VLTI was excellent already in this early stage. For example, the interferometric efficiency ('contrast' on a stellar point source) was measured to be 87% and stable to within 1.3% over several days. This performance will be further improved following additional tuning. The entire operation of the VLTI was performed remotely from the Control Room, as this will also be the case in the future. Another great advantage of the VLTI concept is the possibility to analyse the data at the control console. This is one of the key features of the VLTI that contributes to make it a very user-friendly facility. Overview of the VLT Interferometer ESO PR Photo 10c/01 ESO PR Photo 10c/01 [Preview - JPEG: 400 x 410 pix - 60k] [Normal - JPEG: 800 x 820 pix - 124k] [Hi-Res - JPEG: 3000 x 3074 pix - 680k] Caption : PR Photo 10c/01 Overview of the VLT Interferometer, with the various elements indicated. In this case, the light beams from two of the 8.2-m telescopes are combined. The VINCI instrument that was used for the present test, is located at the common focus in the Interferometric Laboratory. The interferometric principle is based on the phase-stable combination of light beams from two or more telescopes at a common interferometric focus , cf. PR Photo 10c/01 . The light from a celestial object is captured simultaneously by two or more telescopes. For the first tests, two "siderostats" with 40-cm aperture are used; later on, two or more 8.2-m Unit Telescopes will be used, as well as several moving 1.8-m Auxiliary Telescopes (ATs), now under construction at the AMOS factory in Belgium. Via several mirrors and through the Delay Line, that continuously compensates for changes in the path length introduced by the Earth's rotation as well as by other effects (e.g., atmospheric turbulence), the light beams are guided towards the interferometric instrument VINCI at the common interferometric focus. It is located in the subterranean Interferometric Laboratory , at the centre of the observing platform on the top of the Paranal mountain. Photos of some of the VLTI elements are shown in Appendix B. The interferometric technique allows achieving images, as sharp as those of a telescope with a diameter equivalent to the largest distance between the telescopes in the interferometer. For the VLTI, this distance is about 200 metres, resulting in a resolution of 0.001 arcsec in the near-infrared spectral region (at 1 µm wavelength), or 0.0005 arcsec in visual light (500 nm). The latter measure corresponds to about 2 metres on the surface of the Moon. The VLTI instruments The installation and putting into operation of the VLTI at Paranal is a gradual process that will take several years. While the present "First Fringe" event is of crucial importance, the full potential of the VLTI will only be reached some years from now. This will happen with the successive installation of a number of highly specialised instruments, like the near-infrared/red VLTI focal instrument (AMBER) , the Mid-Infrared interferometric instrument for the VLTI (MIDI) and the instrument for Phase-Referenced Imaging and Microarcsecond Astrometry (PRIMA). Already next year, the three 1.8-m Auxiliary Telescopes that will be fully devoted to interferometric observations, will arrive at Paranal. Ultimately, it will be possible to combine the light beams from all the large and small telescopes. Great research promises Together, they will be able to achieve an unprecedented image sharpness (angular resolution) in the optical/infrared wavelength region, and thanks to the great light-collecting ability of the VLT Unit Telescopes, also for observations of quite faint objects. This will make it possible to carry out many different front-line scientific studies, beyond the reach of other instruments. There are many promising research fields that will profit from VLTI observations, of which the following serve as particularly interesting examples: * The structure and composition of the outer solar system, by studies of individual moons, Trans-Neptunian Objects and comets. * The direct detection and imaging of exoplanets in orbit around other stars. * The formation of star clusters and their evolution, from images and spectra of very young objects. * Direct views of the surface structures of stars other than the Sun. * Measuring accurate distances to the most prominent "stepping stones" in the extragalactic distance scale, e.g., galactic Cepheid stars, the Large Magellanic Cloud and globular clusters. * Direct investigations of the physical mechanisms responsible for stellar pulsation, mass loss and dust formation in stellar envelopes and evolution to the Planetary Nebula and White Dwarf stages. * Close-up studies of interacting binary stars to better understand their mass transfer mechanisms and evolution. * Studies of the structure of the circum-stellar environment of stellar black holes and neutron stars. * The evolution of the expanding shells of unstable stars like novae and supernovae and their interaction with the interstellar medium. * Studying the structure and evolution of stellar and galactic nuclear accretion disks and the associated features, e.g., jets and dust tori. * With images and spectra of the innermost regions of the Milky Way galaxy, to investigate the nature of the nucleus surrounding the central black hole. Clearly, there will be no lack of opportunities for trailblazing research with the VLTI. The "First Fringes" constitute a very important milestone in this direction. Appendix A: How does it work? ESO PR Photo 10d/01 ESO PR Photo 10d/01 [Preview - JPEG: 400 x 290 pix - 24k] [Normal - JPEG: 800 x 579 pix - 68k] [Hi-Res - JPEG: 3000 x 2170 pix - 412k] ESO PR Photo 10e/01 ESO PR Photo 10e/01 [Preview - JPEG: 400 x 219 pix - 32k] [Normal - JPEG: 800 x 438 pix - 64k] [Hi-Res - JPEG: 3000 x 1644 pix - 336k] Caption : PR Photo 10d/01 demonstrates in a schematic way, how the images of two stars of different angular size (left) will look like, with a single telescope (middle) and with an interferometer like the VLTI (right). Whereas there is little difference with one telescope, the fringe patterns at the interferometer are quite different. Conversely, the appearance of this pattern provides a measure of the star's angular diameter. In PR Photo 10e/01 , interferometric observations of a single star are shown, as the distance between the two telescopes is gradually increased. The observed pattern at the focal plane clearly changes, and the "fringes" disappear completely. See the text for more details. The principle behind interferometry is the "coherent optical interference" of light beams from two or more telescopes, due to the wave nature of light. The above illustrations serve to explain what the astronomers observe in the simplest case, that of a single star with a certain angular size, and how this can be translated into a measurement of this size. In PR Photo 10d/01 , the difference between two stars of different diameter is illustrated. While the image of the smaller star displays strong interference effects (i.e., a well visible fringe pattern), those of the larger star are much less prominent. The "visibility" of the fringes is therefore a direct measure of the size; the stronger they appear (the "larger the contrast"), the smaller is the star. If the distance between the two telescopes is increased when a particular star is observed ( PR Photo 10e/01 ), then the fringes become less and less prominent. At a certain distance, the fringe pattern disppears completely. This distance is directly related to the angular size of the star. Appendix B: Elements of the VLT Interferometer Contrary to other large astronomical telescopes, the VLT was designed from the beginning with the use of interferometry as a major goal . For this reason, the four 8.2-m Unit Telescopes were positioned in a quasi-trapezoidal configuration and several moving 1.8-m telescopes were included into the overall VLT concept, cf. PR Photo 10f/01 . The photos below show some of the key elements of the VLT Interferometer during the present observations. They include the siderostats , 40-cm telescopes that serve to capture the light from a comparatively bright star ( Photos 10g-i/01 ), the Delay Lines ( Photo 10j/01 ), and the VINCI instrument ( Photo 10k/01) Earlier information about the development and construction of the individual elements of the VLTI is available as ESO PR 04/98 , ESO PR 14/00 and ESO PR Photos 26a-e/00.

The development of the Middle Triassic tectonical controlled Germanic Basin of Central Europe and the palaeoenvironmental related distribution of marine and terrestrial reptiles

NASA Astrophysics Data System (ADS)

Diedrich, Cajus G.

2010-05-01

Nine Middle Triassic paleogeographical maps comprising the uppermost Upper Bunter, Lower to Middle Muschelkalk and Upper Muschelkalk to Lower Keuper time frame (Diedrich 2008b) show the marine ingression and regression cycle of the Middle Triassic Germanic Basin (Diedrich 2010c). For bathymetrical and palaeoenvironmental interpretations especially reptiles and their footprints are used. This Germanic Basin as analogon for the Arabian Gulf (Knaust 1997), north of the Tethys, was under marine and finally terrestrial influenced sediments in a time frame (after Kozur and Bachmann 2008) between 247.2 My (Myophoria Fm, Aegean, Lower Anisian) to 237.9 My (Grabfeld Fm, Longobardian, Lower Ladinian). In a duration of 9.3 My the Germanic Basin was filled up mainly with marine carbonates and at the end by siliciclastics influenced by the northern Tethys through the Silesian, Carpathian and later the Burgundian Gates which connected the Germanic Basin to the Northern Tethys. With the marine ingression from the East via the Silesian Gate (Poland) a ten to hundred kilometers extended intertidal flat to sabkha facies belt surrounded first only the central and then the Western Germanic Basin (Winterswijk, Netherlands). Those intertidal zones were used mainly by two different small reptiles as their primary habitat. Hereby they left Millions of the small tom medium sized footprints of the ichnogenera Rhynchosauroides and Procolophonichnium (Diedrich 2005, 2008a). Larger terrestrial and beach and sabkha adapted reptiles were Tanystrophaeus antiquus and unknown archosaurs, which are recorded only by their footprints. At the beginning of the ingression at the uppermost Bunter a shallow marine invertebrate fauna and coastal reptiles appeared in the Germanic Basin which must have originated mainly from the Northern Tethys. Especially all marine reptiles immigrated from the Tethys which is proven not only by assamblaged Tethyan cephalopod Ceratite species (cf. Diedrich 2008a). The coastal intertidal zones appeared with mud cracked biolaminate and sabkha dolomites ("Biolaminate and Sabkha facies") and expanded further west and south within the Lower Muschelkalk Winterswijk Fm (Aegean/Bithynian boundary), Osnabrück Fm, and Jena Fm (Bithynian to Pelsonian) (Diedrich and Trostheide 2007, Diedrich 2008a). The intertidal zones changed their extensions several times in the Lower Muschalkalk due to the less eustatically and more tectonically controlled very shallow relief cratonic basin morphology and were more stable in the western part of the flat carbonate ramp basin (Winterswijk, Netherlands) and in coastal zones in general. In the Germanic Basin centre (Rüdersdorf to Gogolin, Germany/Poland) the conditions were all that time under very shallow carbonate sand barr (Oolithtic, Terebratula or Shell bioclastic facies) or shallow subtidal ("Wellenkalk facies") conditions, whereas even extended seagrass meadows in shallow carbonate facies types are indirectly proven by invertebrate communities, especially snails. Those algae attracted especially placodontids which were the "Triassic seacows" feeding on such algae (Diedrich, 2010a), which immigrated with Paraplacodus, Placodus and Cyamodus already with the first Lower Muschelkalk ingression sequence. Also other reptiles such as nothosaurs Nothosaurus (small species), Cymatosaurus, the pachypleurosaurids Dactylosaurus, Neusticosaurus or Serpianosaurus must have originated from the tethys and were shallow marine and even lagoonary adapted paraxial swimming smaller marine reptiles. This "Lower Muschelkalk" time was highly tectonically active represented by several seismic layers (slumps, sigmoidal shocked layers, etc.) (cf. Schwarz 1975, Rüffer 1996, Knaust 2000, Diedrich 2008a), which were also reaching the intertidal beach zones, possibly even with tsunamite hazard events (Diedrich 2008b, 2009b). Such tsunamis or quick floodings due to storm events must have had hazardous impacts on marine reptiles or fishes, and the beach inhabiting terrestrial reptiles, which could have been killed by high amounts which explains the presence of many skeletons, bonebeds, and footprint preservations in the Germanic Basin biolaminate and lagoonal facies. With a high seismic peak during the Middle Muschelkalk Karlstadt Fm (Pelsonian/Illyrian boundary) in the intertidal zones up to 19 tectonically shocked biolaminate layers (locality Bernburg, Central Germany, Diedrich 2009b) prove the beginning of the Alpine tectonics and its raise (fold belt structure: Müller et al. 1964), but also the opening of the Carpathian Gate (graben structure: Szulc 1998), from which the epicenters were estimated by two main slickenside directions. Those can be found all over the Germanic Basin "Lower Muschelkalk" sediments (Szulc 1998, Föhlisch 2007, Diedrich 2009b). This time period of the Pelsonian/Illyrian boundary gave even such extended intertidal zones, that reptiles left Millions of tracks all over those biolaminate facies types, allowing those to migrate and distribute East (Bohemian Island) - West (Rhenisch Massif, London-Brabant Massif) due to "intertidal flat bridges". Therefore chirotherid archosaur trackmakers left Chirotherium, Isochirotherium and Brachychirotherium trackways quite abundantly not anymore in the typical Bunter red sandstone facies; now they appeared in the new environments, the intertidal biolaminates such as well documented at Bernburg (Central Germany, Diedrich 2009b), but also on other Middle Triassic coast east of the Massif Central (Demathieu 1985) or the Alps (e.g. Avanzini 2002). The only surviving marine reptiles were smaller lagoonal adapted pachypleurosaurs such as the common Anarosaurus and smaller sized Nothosaurus. Placodontids disappeared with the loss of the palaeoenvironment of the macroalgae meadows and seem to have migrated to the Carpathian gate and northern Tethys, where those habitats were still present. The dramatical habitat change with terrestrial territory loss, and marginal marine beach zone extensions seem to be also the reason for the beginning of the dinosaur raise in the world. Within the Middle Muschelkalk Heilbronn and Diemel Formations a massive sea level fall caused a new extension of intertidal zones and sabkhas, but also halite and gypsum evaporates ("Domolite-evaporate facies") in the basin center including the southern Germanic Basin branch (region Tübingen/Stuttgart, Southwestern Germany). The "Middle Muschelkalk" shallow relief and lagoon to intertidal dominated period changed again drastically within a new tectonic active "Upper Muschelkalk" time and strong "ingression" of the northern Tethys into the Germanic Basin within the Illyrian time (Bad Sulza Fm, Trochitenkalk Fm). A shallow marine, with shallow water carbonates filled Germanic Basin developed again, but this time with different consequences onto the former coastal zones, in which intertidal biolaminated and sabkhas disappeared as a result of steeper coastal morphologies. Whereas in the first ingression a shallow marine reptile fauna was present (Nothosaur-Pachypleurosaur taphocoenosis, Lower Bad Sulza Fm, Diedrich in prep.). The fauna changed with the main transgression within the Upper Bad Sulza Fm to a Placodontid-Pistosaur taphocoenosis with more open marine adapted forms (Diedrich in prep.). At those time also crinoid bioherms developed massively all over the central and southern Germanic Basin in front of the costs at the "steeper coast margins" (which were still hot high angled), as a "crinoid belt" (e.g. Aigner and Bachmann 1991), which was responsible for massive crinoidal limestones (= "Trochitenkalk facies"). In this period again "Triassic seacows" seem to have populated well the entire Germanic Basin, and here again seagrass meadow areas documented by benthic invertebrate palaeocommunities (Diedrich 2009a, 2010a). The marine macroplants must have built extended meadows on the shallow marine and oxygen-rich seafloor conditions of the "Tonplatten facies" on which many different invertebrates settled in- or epifaunistic. This tectonical deepening controlled situation continued with the Meißner Fm and aequivalent Formations and its cephalopod Ceratite rich "Tonplatten facies", whereas the "maximum flooding" (if the term can be used here in a cratonic and tectonically controlled basin: cf. definition of marine cycles in: Aigner and Bachmann 1991) was in the compressus biozone (ceratite biozone, middle Meißner Fm, Anisian/Ladinian boundary, cf. Diedrich 2009a). The high stand is underlined by now full adapted marine reptiles such as nothosaurs (Nothosaurus mirabilis, Simosaurus gaillardodti), pistosaurs (Pistosaurus longaevus) and especially the open marine ichtyosaurs (Shastasaurus, Mixosaurus, Omphtalmosaurus) support the full marine and highest water level conditions. The "regression" or better suggested here "basin uplifting" started in the upper Meißner Fm with a reducing carbonate sedimentation which was overtaken slowly by terrestrial sediments already within the Warburg/Erfurt Formations (Fassanian/Longobardian boundary, Lower Ladinian). The fresh water and clay mineral influence caused a reduction of the marine benthic community biodiversity and the development of brackish lagoons, in which some invertebrate faunas and dominantly small marine reptiles pachypleurosaurs lived. At that time all placodontid reptiles disappeared, which must have been the chain reaction of the macroalgae loss and environmental changes. A change of terrestrial influence and periodic marine influence is documented in repeating intercalated massive dolomites (Alberti-Bed, Anthraconit-Bed and others) and clay layers of the Lower Keuper Erfurt and especially Grabfeld Fm (Longobardian). In this final period the Lower Keuper Germanic Basin was less and less marine influenced, finally dominated at that time on the limnic influenced costs by large amphibians such as Mastodonsaurus, Gerrhothorax or Plagiosuchus, which were found especially at southern German and Central german sites (Schoch and Wild 1999, Diedrich 2010b), including the famous southern German "Grenzbonebed" (Fassanian/Longobardian boundary) (Reif 1982, Hagdorn 1990). This bonebed already contains a strongly reduced marine reptile fauna with pachypleurosaurs and giant lagoon-adapted nothosaurs (N. giganteus, S. gaillardoti) and few marine hypersaline adapted shells such as Costatoria costata (cf. Hagdorn et al. 2009). The absence of cephalopod ceratites and rare nautilid presence are the last proves for the periodic restricted lagoon situations- being comparable in its facies and reptile fauna to the lagoon of the Northern Tethys Monte San Giorgio, Switzerland/Italy (e.g. De Zanche and Farabegoli 1988, Furrer 1995) to which the Germanic Basin was connected through the Burgundian Gate, France. The marine influence and marine sediment fill of the Germanic Basin stopped finally at the beginning of the Middle Keuper (lower Upper Triassic), diachronously more earlier in northern Germany (Warburg/Erfurt Fm, cf.: Kozur and Bachmann 2008, Diedrich 2010b) as in southern Germany (cf. Hagdorn et al. 2009) indicating a periodic marine influence from the Northern Tethys through the Burgundian Gate. At the final tectonical stage (last seismits in the Grabfeld Fm, Longobardian: cf. Bachmann and Aref 2005) no intertidal flats nor biolamnintes developed anymore in a low relief Germanic Basin morphology, which reason can be explained be the carbonate reduction, strong terrigenous clay input, and brakish-lagoonary conditions, in which cyanobacterial mats of the low-relief intertidal zones could not develop. References Aigner, T. and Bachmann, G.H. 1991. Sequence Stratigraphy of the German Muschelkalk. In: Hagdorn, H. and Seilacher, A. (Eds.): Muschelkalk. Schöntaler Symposium. 15-18. Goldschneck-Verlag, Stuttgart. Avanzini, M. 2002. Dinosauromorph tracks from the Middle Triassic (Anisian) of the Southern Alps (Valle di Non-Italy). Bolletino della Società Paleontologica Italiana, 41 (1), 37-40. Bachmann, G.H. and Aref, M.A.M., 2005. A seismite in Triassic gypsum deposits (Grabfeld Formation, Ladinian), Southwest Germany. Sedimentary Geology 180, 75-89. De Zanche, V. and Farabegoli, E. 1988. Anisian paleogeographic evolution in the Central-Western Southern Alps. Memoirs Scientifique Geologique 40, 399-411. Demathieu, G.R. 1985. Trace fossil assemblages in Middle Triassic marginal marine deposits, eastern border of the Massif Central, France. Societe Economie Paléontologie et Mineralogie, Special Publications, 35, 53-66. Diedrich, C. 2005. Actuopalaeontological trackway experiments with Iguana on intertidal flat carbonates of the Arabian Gulf - a comparison to fossil Rhynchosauroides tracks of Triassic carbonate tidal flat megatracksites in the European Germanic Basin. Senckenbergiana maritime, 35 (2), 203-220. Diedrich, C. 2008a. Millions of reptile tracks - Early to Middle Triassic carbonate tidal flat migration bridges of Central Europe. Palaeogeography, Palaeoclimatology, Palaeoecology, 259, 410-423. Diedrich, C. 2008b. Palaeogeographic evolution of the marine Middle Triassic marine Germanic Basin changements - with emphasis on the carbonate tidal flat and shallow marine habitats of reptiles in Central Pangaea. Global and Planetary Change, 65 (2009), 27-55. Diedrich, C. 2009a. The vertebrates of the Anisian/Ladinian boundary (Middle Triassic) from Bissendorf (NW Germany) and their contribution to the anatomy, palaeoecology, and palaeobiogeography of the Germanic Basin reptiles. Palaeogeography, Palaeoclimatology, Palaeoecology, 273 (2009), 1-16. Diedrich, C. 2009b. Die Saurierspuren-Grabung im basalen Mittleren Muschelkalk (Anis, Mitteltrias) von Bernburg (Sachsen-Anhalt). Archäologie in Sachsen-Anhalt, Sonderband 2009, 1-62. Diedrich, 2010a. Palaeoecology of Placodus gigas (Reptilia) and other placodontids - macroalgae feeder of the Middle Triassic in the Germanic Basin of Central Europe and comparison to convergent developed sirenia. Palaeogeography, Palaeoclimatology, Palaeoecology, (in review). Diedrich, 2010b. The vertebrate fauna of the Lower Ladinian (Middle Triassic) from Lamerden (Germany) and contribution to the palaeoecology, anatomy and palaeogeography of the Germanic Basin reptiles. Palaeogeography, Palaeoclimatology, Palaeoecology, (in review). Diedrich, 2010c. The palaeogeographic reconstructions of the Middle Triassic tectonical controlled carbonatic Germanic Basin of Central Europe - a northern Tethys connected cratonic marine Basin - coastal basin margin mappings by the use of reptile footprint rich intertidal and sabkha environments. Abstract, Fifth International Conference on the Geology of the Tethys Realm, Quena-Luxor,Egypt), 3-5. Diedrich, in prep. The shallow marine fish and sauropterygian reptile vertebrate fauna of the Germanic Basin from the atavus/pulcher Bonebeds in the Bad Sulza Fm (Illyrian, Middle Triassic) of Bad Sulza (Central Germany). Diedrich, C. and Trostheide, F. 2007. Auf den Spuren der terresten Muschelkalksaurier und aquatischen Sauropterygier vom obersten Röt bis zum Mittleren Muschelkalk (Unter-/Mitteltrias) von Sachsen-Anhalt. Abhandlungen und Berichte für Naturkunde, 30, 5-56. Föhlisch, K. 2007. Überlieferungen seismischer Aktivität im Unteren Muschelkalk. Beiträge zur Geologie Thüringens, N.F. 14, 55-83. Furrer, H. 1995. The Kalkschieferzone (Upper Meride estone Ladinian) near Meride (Canton Ticino, Southern Switzerland) and the evolution of a Middle Triassic intraplatform basin. Eclogae geolicae Helvetiae, 88(3), 827-852. Hagdorn, H. 1990. Das Muschelkalk/Keuper-Bonebed von Crailsheim. In: Weidert, W. K. (Ed.), Klassische Fundstellen der Paläontologie, Band 2. 78-88. Goldschneck-Verlag, Stuttgart. Hagdorn, H., E. Nitsch, Aigner, T. and Simon, T. 2009. Field guide 6th international Triassic field workshop (Pan-European Correlation of the Triassic) Triassic of Southwest Germany. September 7-11, 2009, www.stratigraphie.de/perm-trias_workshops.html, 1-72. Knaust, D. 1997. Die Karbonatrampe am SE-Rand des Persischen Golfes (Vereinigte Arabische Emirate) - rezentes Analogon für den Unteren Muschelkalk der Germanischen Trias? Greifswalder Geowissenschaftliche Beiträge, 5, 101-123. Knaust, D. 2000. Signatures of tectonically controlled sedimentation in Lower Muschelkalk carbonates (Middle Triassic) of the Germanic Basin. Zentralblatt für Geologie und Paläontologie, I, 1998 (9-10), 893-924. Kozur, H.W. and Bachmann, G.H. 2008. Updated correlation of the Germanic Triassic with the Tethyan scale and assigned numeric ages. Berichte der Geologischen Bundesanstalt Wien, 76, 53-58. Reif, W.E. 1982. Muschelkal/Keuper bone-beds (Middle Triassic, SW-Germany) - storm condensation in a regressive cycle. In: Einsele, G. and Seilacher, A. (Eds.), Cyclic and Event Stratification. 299-325. Springer-Verlag, Berlin-Heidelberg-New York. Müller, W. et al., 1964. Vulkanogene Lagen aus der Grenzbitumenzone (Mittlere Trias) des Monte San Giorgio in den Tessiner Kalkalpen. Eclogae geolicae Helvetiae, 57(2), 431-450. Rüffer, T. 1996. Seismite im Unteren Muschelkalk westlich von Halle (Saale). Hallesches Jahrbuch für Geowissenschaften, B 18, 119-130. Schoch, R. and Wild, R. 1999. Die Wirbeltiere des Muschelkalks unter besonderer Berücksichtigung Süddeutschlands. In: Hauschke, N. and Wilde, V. (Eds.), Trias eine ganz andere Welt. Europa im frühen Erdmittelalter. 331-342. Pfeil-Verlag, München. Schwarz, U. 1975. Sedimentary structures and facies analysis of shallow marine carbonates (Lower Muschelkalk, Middle Triassic, SW-Germany). Contributions to Sedimentology, 3, 1-100. Szulc, J. 1998. Anisian-Carnian evolution of the Germanic Basin and its eustatic, tectonic and climate controls. Zentralblatt für Geologie und Paläontologie, I, 7-8, 813-852.

hwhap_Ep30_Infamous Meteorites

NASA Image and Video Library

2018-02-01

Gary Jordan (Host): Houston, We Have A Podcast. Welcome to the official podcast of the NASA Johnson Space Center, Episode 30, Infamous Meteorites. I'm Gary Jordan, and I'll be your host today. So on this podcast, we bring in the experts, NASA scientists, engineers, astronauts, all to let you know the coolest stuff about what's going on right here at NASA. So today, we're talking about some of the more unique findings that have been discovered in meteorites with David Mittlefehldt, goes by Duck. He's a planetary scientist here at the NASA Johnson Space Center in Houston, Texas, and we had a great discussion about curious findings in meteorites, and the adventures that are endured to procure them. So, with no further delay, let's go lightspeed and jump right ahead to our talk with Dr. Duck Mittlefehldt. Enjoy! [ Music & Radio Transmissions ] Host: Duck, thanks for coming to the podcast today. I know we've -- we've talked about searching for life and meteorites before, and it's -- it's such a fascinating topic, but I really wanted to dive deeper, just into like the meteorites portion. We really -- we really actually had a great conversation with Dr. Aaron Burton and -- and Dr. Marc Fries, not too long ago, actually, about life, but really just about the meteorites themselves. There's a -- there's a big story there, and you're one of the explorers that are going down and actually finding these meteorites, huh? Dr. Duck Mittlefehldt: Yeah, yeah. I've done that on a number of occasions. Host: Yeah. And it's -- is it -- is it mostly in Antarctica, or are you going other places? Dr. Duck Mittlefehldt: Well, okay, so most of the times I've been searching for meteorites has been in Antarctica, so I've been down there five times, meteorite collecting expeditions, but I -- I've [pause] -- I was on vacation in Israel once, and I met up with a couple of geologists at a coffee house, and one of them had just published a paper where they -- he described, you know, old surfaces in the deserts of southern Israel that are, you know, have been stable for about 2 million years. And I'm thinking, you know, over 2 million years, you can accumulate a lot of meteorites, so, I actually went there the foll -- later that year, and met up with them again, and we searched some of these areas that are -- have very ancient pavements on the desert, and hunting for meteorites. We didn't find any, unfortunately, and, you know, I'm not quite sure why, there -- there should have been some there, but, you know, it was a small team searching large area over short time, so it may well be that they're there, but we just didn't find any, because the ones that, you know, are there are small. The other is there were a number of issues with that particular location. Meteorites, you know, when we find meteorites, they're typically black on the outside, because they've gone through the atmosphere and they're covered with this glassy, fusion crust, which is almost always black. The area we had searched in southern Israel actually had a number of dark rocks in it, as well. So, you know, the meteorites, if they were there, would not have stood out as -- like -- like, you know, the beacons that you see when you're in Antarctica, scooting across the bare ice, so. Host: I guess that -- is that the main reason why Antarctica is such a great place to find meteorites? Is because it's these black rocks against white snow? Dr. Duck Mittlefehldt: Well, that certainly makes it easy, because [Gary laughing] you -- you can see, you know, a rock, I'm going to use metric units because that's what I'm used to, I'll try and remember to throw in inches and feet as I can, but, so, you know, you can find a -- a black rock, a couple of centimeters across or about an inch across, from a great distance in Antarctica on the ice. And -- and, as you say, it's because you're looking at either pale blue ice or sometimes white snow, most of the meteorites we find are on the pale blue ice. But even so, it's very bright in comparison to rock. So they're easy to find there. The other thing is in Antarctica, we have a convenient concentration mechanism, which is the actual flow and ablation of the ice across the continent, and where we go to find them the meteorites is -- is actually in locations where the ice movement has been stalled, and ablation by the Antarctic winds and -- and warming by the Antarctic sun, allow a lag deposit to develop on the surface. So we're actually collecting meteorites that have been, you know, shoved from a great geographic area and then left behind in a smaller geographic area. So we have, you know, base -- we have both the easy-to-spot and -- and the concentration mechanism working in our favor. Host: Alright! Yeah, they're -- they're plentiful down there. So -- so you made quite a few trips. How many was it? You said five? Dr. Duck Mittlefehldt: Yeah, I've been down five times. The first time was in the '97, '98 field season. That was my first Antarctic experience, and I loved it so much I kept volunteering to go back again. Host: You loved Antarctica? Dr. Duck Mittlefehldt: Oh yeah [Gary laughing], I -- I love it, you know, just -- just last week, well, here in Houston, we had temperatures that Houstonians think of, or Texans think of as cold, but, me, I see that as maybe a cold fall day. Because I -- I was born and raised in western New York. Host: Alright. Dr. Duck Mittlefehldt: And at the same time, you know, my hometown was getting temperatures, okay, again, I've got to do some conversion here, about maybe, you know, between 0 and 5 degrees Fahrenheit. And, you know, that was the weather I grew up in winter, and I loved it. Winter was always my favorite season when I was a kid. Alright. So maybe it's a deep love of winter that really -- because I just came from this -- we're just coming back from the holidays now, and it was -- it was negative 2 in Pittsburgh when I -- when I was flying home, and, I mean, I was -- I was born and raised in Pennsylvania, moved around a lot, but I'm not used to it by any means. Like, I like the -- I like the, everyone, you know, saying, oh my gosh, 32 is really cold! And I'm like, [laughing], I'm okay with just that. Host: For me, I -- I loved the deep winter in western New York. Dr. Duck Mittlefehldt: Alright, a lot of snow there too. Host: So when was the last time you were down in Antarctica then? Dr. Duck Mittlefehldt: So I was down last year, 2016, 2017, it was kind of a disappointment for me, personally. Host: Oh. Dr. Duck Mittlefehldt: I -- I -- because of my experience, I've been down four times before, I -- I left early and was going to go out on a recon sweep with the -- the mountaineer field safety officer for the ANSMET program. ANSMET, by the way, stands for Antarctic Search for Meteorites, and that's the program that goes down to collect the rocks and has been doing so every year, but once, since 1976. Host: Alright! Dr. Duck Mittlefehldt: But, anyway, because of my experience, I was going to go down on this recon before the main season. We were going to go to one area, check it out for potential systematic work in a future season, and then stay for the first half of the main season, going to a location deep along the Antarctic, transAntarctic mountains. Well, it turns out logistics were badly broken last year. And partly because of weather, partly because of problems with the aircraft and so on, so I got out into the field for a week, in preseason, I got back to McMurdo Station while we were gearing up for the main season, but the logistics just broke and so they were not going to go out where they originally planned. The team ended up going to where I had been out on recon, but it was -- they got such a late start that it made more sense to ship me home early rather than, you know, go out for maybe a week and then come back into McMurdo and go home. Host: Yeah. Dr. Duck Mittlefehldt: So I -- I just spend one week out in the field last year. Host: Ahh... Dr. Duck Mittlefehldt: Much -- much to my chagrin. Host: [Laughing] So it was just the lack of time that you spent there, that was really the disappointment. Yeah, yeah, it was [inaudible] time, and, you know, in the brief time that John Scott [phonetic] and I, he's the mountaineer, were out on the ice, you know, we -- we'd spend a week in the field, two and a half days we were tent-bound because the weather was so bad, but even so, we found 46 meteorites in the short time we were there. Host: That's amazing! Yeah. Host: Wow. Dr. Duck Mittlefehldt: And -- and remind -- and remember, this was an area that had been heavily harvested back in the 80's, 70's and 80's, we were going to back to see whether there was still great potential for harvesting more meteorites there, and, in fact, I think last year they ended up coming -- picking up a total of 200 and some meteorites, even with, you know, going back to an area that had been searched before, and having a shortened season because the logistics. So, I mean, that -- that kind of shows you the -- the quality of Antarctica as a -- as a site for bringing back space rocks. It's just awesome! Host: Incredible! So is -- is that -- is it because there's just a fresh, I guess you could call it, supply of meteorites that are landing on the surface of Antarctica, or is it things are shifting? Dr. Duck Mittlefehldt: It's more things are shifting. In part, you know, deflation of the surface continues, as ablation goes on, and so new meteorites are poking through. In part, it's shifting winds blowing snow around, so an area that might have been snow covered earlier season, maybe now has been stripped bare and there's bare ice. And so that allows you to see things. So for a variety of reasons, you can go back to the same place you've searched once, and -- and still find meteorites out there. Host: Incredible. And hundreds of them, a little bit better than Israel, right? Dr. Duck Mittlefehldt: Yeah [laughter]. Might have been better than my experience trying to find meteorites in the Negev Desert. Host: [Laughing] So -- so you're saying a season. When you're going down to Antarctica, I'm assuming it's the summer there, right? Dr. Duck Mittlefehldt: Yeah, it's austral summer. Host: Yeah. So that means the sun is up 24/7, right? Dr. Duck Mittlefehldt: Right. Host: So you kind of have to deal with that when you're -- when you're down there, right? Dr. Duck Mittlefehldt: Yeah, you know, I've -- I've become accustomed to that. The first -- I was kind of -- there was a guy who used to work in our building who had been down I think a year or two before me, so I took advice from him, and he said, you know, one of the things is, you know, with the constant sunlight, sometimes sleep can be a problem. So I bought a heavy, black knit hat, and, you know, I just put that on as my sleep hat, and then pulled the brim over my eyes, and so everything was black. So I -- I could sleep fine down there. Host: Oh, nice! Dr. Duck Mittlefehldt: But the, you know, the main advantage is that because the sun's up 24/7, you're not really bound by the 9 to 5 time sequence. Host: Oh, yeah. Dr. Duck Mittlefehldt: So, as I said, when we -- when I was out last year in the -- in the recon site, we were there for a week, you know, we -- we landed, got our gear, and then went, spent a half a day out, then the -- the winds blew in, it was too windy and cold to go out, so the winds broke around noon one day, or a little bit after noon. We decided we would have an early supper and then go out and collect -- harvest meteorites. So that day, we ended up getting out of the tents maybe 5 o'clock in the evening, and we worked about till 30, 2 in the morning. Host: Woah! Dr. Duck Mittlefehldt: The sun was up, it was perfectly fine, it was just my age and body crapping out at 30 [Gary laughing]. I, you know, I just couldn't pick up another meteorite if -- if they beat me with a stick. You know, I was just so tired. But then, you know, that's -- that's something you can do down there that you can't do here. Host: Yeah, did you know the hours were going by, or did you have no sense of time with the -- with the sun being up? Dr. Duck Mittlefehldt: Well, you know, you can trace the sun, if you pay attention, you can get a sense of the day, because the sun does a lazy loop in the sky, and... Host: Oh. Dr. Duck Mittlefehldt:...and so, you know, once you've located yourself, you know where north, south is, [pause] there is still north and south, even that close to the pole. Host: Yeah. Dr. Duck Mittlefehldt: But, you know, you know at midnight, the sun is going to be, you know -- you know, at one -- at the one position, so. Host: Right. Dr. Duck Mittlefehldt: And it's kind of at the lowest point far north, and so, you know, you can track it that way, but basically I didn't pay attention. We were just so busy, you know, driving from place to place harvesting meteorites that, you know, it was just constantly moving, doing the next one, taking the data, collecting it, you know, cleanly and safely and getting it in the bag and moving on to the next location. Host: Oh, so are you -- are you not -- you're not stationary then when you -- when you kind of set up camp. Are you -- are you kind of mobile, like with your camp, and you just move it from one meteorite site? Dr. Duck Mittlefehldt: No, no. Host: Oh, okay. Dr. Duck Mittlefehldt: The camp is usually -- there are a couple -- there are a couple of ways that it is done. When we do systematic searching, the camp is stationary in one spot, perhaps for the whole field season, and you just go out, day-to-day, to different locations. And that's what we did here. We were on recon, so we -- we plunked the tent down, then we searched within easy skidoo range of the camp. Sometimes, and I've done this before, go down on a recon time, where -- where you go and you put camp down, you might prospect an area for two, three weeks, then you move camp to another area and prospect there for two or three weeks. So, there -- there are -- those -- there are those two types of scenarios, and even in the recon mode, you know, you're -- the tent -- the camp is stationary for two or three weeks, and you're skidooing all around that area to -- to search it, and then you only pick up tents and camp and move to a far distant area to recon that general region. Host: Alright! Alright, well I'm guessing, you know, going down there so many times, you're quite an expert in making sure that, you know, you can survive weeks and weeks and weeks in Antarctica. So, what are the -- some of the stuff that you're taking down there that I guess are unique to the Antarctic environment? Dr. Duck Mittlefehldt: Okay, so, most of the gear you get, you get in Christchurch, so, you know, living in Houston, I don't have a winter coat. Host: Oh! Dr. Duck Mittlefehldt: So, at -- at the clothing distribution center in Christchurch, you'll get outkitted -- outfitted with, you know, heavy -- heavy jackets, all the gloves you can want, thermal pants, fleece liners, boots, hats, everything you need to survive, and then in McMurdo Station, you actually get the camping gear, the tents, the cook stoves, the dishes, the food, sleeping bags, that sort of stuff. So all -- all the intrepid Antarctic explorer needs to take down with them are personal items, like I mentioned my knit hat, that -- that was mine, and that was because I knew I wanted something to sleep in. I, you know, I bought extra pairs of thermal underwear, because the first time I went down, you know, they -- they give you two sets, but you're out in the field for six or seven weeks, so you want to change, you know, once in a while. [Gary laughing] Other than that, you know, my glasses are prescription, and so I buy glasses that transition dark and sunlight, so I can just, you know, wear my normal glasses out on the skidoo, I have actually bought glacier glasses, so I have side shields and whatnot to block the light. You want to -- one of the things that really is critical down there is to block all light from your eyeballs, you know, other than what gets filtered through a dark lens, because, otherwise, snow blindness is a problem. Host: Oh, that's right! It's so bright down there, right? Yeah. Dr. Duck Mittlefehldt: So I do that, but, otherwise, you know, most of the gear they give you, they loan it to you for the time that you're out there, and -- and so, you know, you could survive on just what you get from the Antarctic program down in Antarctica. It wouldn't necessarily be entirely comfortable wearing the same clothes, you know, for seven weeks, but you could do it. Host: [Laughing] So -- so your -- this Antarctic program, that -- that's ANSMET, right? Dr. Duck Mittlefehldt: Right. Host: Okay, so what's the -- what's the relationship between ANSMET and NASA, and how that all works together? Dr. Duck Mittlefehldt: Well, originally, ANSMET was set up as a three agency agreement. So the -- the -- it was funded -- the actual Antarctic search for meteorites was funded through the National Science Foundation, because they have -- they do the scientific research in Antarctica. NASA funded the curation and allocation of meteorite samples here at NASA Johnson Space Center, and then the Smithsonian Institution did the initial classification and was the long-term repository for the meteorites collected in Antarctica. That, since -- since then, they've changed it, and now NASA actually funds the Antarctic, the ANSMET research component. NSF still supplies the logistics, but NASA pays NSF for those, those logistics, because they -- they are the, I mean, they have all the logistics in Antarctica. And -- and the rocks still go, ultimately, to the Smithsonian, a chip for initial classification, and rocks that are no longer actively being researched by scientists in the world end up being permanently curated at the Smithsonian Institution. So that is -- that is still the way things are run. Host: Alright. So -- so is the ones that people are researching, and actively studying, are all of them housed here at the Johnson Space Center? Dr. Duck Mittlefehldt: Yes. With some exceptions. We don't have the necessary facilities to easily deal with metal-rich meteorites. So iron meteorites, stony iron meteorites, automatically go, ah, nope, I'm going to pull that back. Iron meteorites automatically go to the Smithsonian Institution. Because they are equipped for -- to cut metal and -- and make samples available. We do do the stony meteorites here, I forgot about that, because I've gotten some from here. So those that have a significant stony component are still worked on here until they become no longer of scientific interest. But, you know, even though they go to the Smithsonian for permanent curation, they're -- they're not dead to science, so to speak. So I can request samples that have been housed at Johnson Space Center for years, and now transfer -- transformed permanently to the Smithsonian if -- if I find, you know, an interesting project to do on one of these old samples. And I actually have gotten, in the past, some samples from the Smithsonian that were originally from the Antarctic collection. Host: Wow. So back in Antarctica, when you're looking at these meteorites and you're trying to, you know, figure out what they are, are they, you know, more stony, more metal-rich, what are you using to -- to look at them, to find out more about them and say, yes, that's a meteorite that I want to get my hands on? How do you know what's the good stuff? Dr. Duck Mittlefehldt: Uh, decades of experience. Host: There you go [laughing]. Dr. Duck Mittlefehldt: So, I, you know, I can look at a rock in Antarctica, and I can already make a preliminary classification. Sometimes I'm wrong, and -- and, you know, the guy who has more experience than anyone is -- is our mountaineer field safety officer, John Scott, and, you know, he -- he can look at a rock, and, in many cases, give a pretty good guess as to what it's going to turn out to be. And, you know, I can do that with a lot of different types of rocks, especially those that I'm interested in, but all in all, there -- there are always those meteorites that come back that either no one has ever seen before, because it's totally new, or it's enough different from the norm for that class that it just doesn't -- doesn't appear to be what you think it is, in hand sample. So, and we don't -- and we don't, you know, in Antarctica, we don't do anymore than a very high-level classification. Yes, this is a stony meteorite, it's probably a chondrite, this is probably a carbonaceous chondrite, this is probably an achondrite, which is a type of meteorite that's been melted. This is probably a stony iron, an iron, and so forth. And, to some extent, we need to do that because certain types of meteorites have more scientific value than others. So -- so, for example, a very primitive carbonaceous chondrite is -- is probably going to get a lot of research attention when it's announced. And so we collect those in a special way to try and minimize contamination by organic compounds. And that's why we need to be able to say, oh, yeah, you know, stand back from this guy, we need to treat him differently than -- than this one over here. Host: Alright. And then, obviously, you know, knowing where to ship it too, right? Because some of the metals one have to go the Smithsonian...? Dr. Duck Mittlefehldt: So that -- no, that's all done here. Everything is shipped here to Johnson Space Center. Host: Oh, everything comes here, okay. Dr. Duck Mittlefehldt: And -- but the difference is when they -- when they open some that are listed in the -- in the notes as probably being iron meteorites, they -- they will warm them up in the dry nitrogen cabinets, look at them, and if they agree, you know, they'll do an external description, you know, this is a brown rock, you know, 10 centimeters in size and weigh so much, and we don't see anything in it, you know, out of the ordinary, from the outside, then the whole thing will -- then that whole rock will get shipped to the Smithsonian at that point, and there, they'll cut it open with a wire saw, if it's, you know, indeed, probably metal, and then make a polished mount and etch it to bring out the texture and so forth. Host: Alright! And then that's what you mean by the facilities, right? They have the -- the proper facilities to do that. So what about here? What kinds of equipment and facilities do we have to make sure that we're handling all of this properly? Dr. Duck Mittlefehldt: So, in the meteorite processing lab, we have [pause] -- we use tools of a very limited set of composition. So, typically, stainless steel hammers and chisels, and -- and the reason is, you know, no matter what we do with a rock from space, we're going to contaminate with something from earth. So the object is to, one, minimize that contamination. So we use materials that we know are not going to, you know, just shed particles everywhere, for example, but also if we -- we use always the tools of the same -- of a given composition so that we know that if we see something like this in the rock, oh yeah, that must have come from the tool. And, you know, I've seen this, rocks are hard to break, and so, you know, your -- your choices are to saw them open or to use a hammer and chisel, and I have seen on a rock that I've gotten, a flake from the chisel that rubbed off. Metal, you know, it's soft, even hardened steel will rub off on occasion. So, you know, I can see this, I can pull that contaminant off or isolate it, in the lab, but, you know, I know then I can do a simple test, yes, that's from the chisel, I don't have to worry about that. I've taken care of it, the rest of the sample is fine. So the object is to minimize contamination or to know what the potential contaminants are. And, you know, there's no way you know of getting -- there's -- with modern technology, we can't, you know, we don't have magnetic levitation devices that we then use a laser to slice them open cleanly. You know, we -- we do with what we got. This isn't Star Trek here yet. Host: [Laughing] We'll just stick with the hammer and chisel for now. So, I mean, when you're cutting these open, and you open them up, what -- what are you looking at? Are you looking at just the rock or are you taking even smaller chunks of that? How is that working? Dr. Duck Mittlefehldt: Well, that all depends on the question that you're trying to answer, and I've done both where I've asked for samples of a, what's called a bulk sample of the rock, so something as representative of the entire rock as possible, and I've looked for individual class in the rock, little fragments that are of a specific type within the rock. All of this is basic 19th century geology, in many respects. You know, in the 19th century, geologists would go out in the field with their hammers, they'd -- they'd beat on a rock and use a hands lens to look at the microscopic, yeah, microscopic texture, mineralogy in it, and, you know, a trained geologist can do the same with a meteorite, and say, yeah, okay, I can see -- I can see what this is, it's a certain type of rock type in there, and that's what I want, I don't want this part over here. So, you know, the traditional geologic methods,but with modern equipment, can be used, and -- and, you know, there's -- there's nothing like the human eye in the brain for sorting out who's who in the zoo. Host: [Laughing] So then how can you -- what -- what are some of the key differences for the -- for the non-geologically-trained eye for whenever you're looking at a rock and you can, you know, you cut it open and you look and you say, that's a meteorite, that's not from earth? Or, this is definitely from earth? Dr. Duck Mittlefehldt: Okay, the -- the first key is -- - is fusion crust. I mentioned this earlier. Host: Oh yeah. Dr. Duck Mittlefehldt: And that -- that's where, going through the atmosphere, friction with the air causes the outer surface to melt, and actually, you know, little bits are flying off all the time, the meteorite we get on the surface is just a small piece of what entered the atmosphere. Most -- sometimes the vast majority of it just ablated away in the atmosphere into little droplets or dust. Host: Wow. Dr. Duck Mittlefehldt: So, you know, if you see a fusion crust on the rock, right away, you know it's -- it's a meteorite, you don't have to go any farther than that. In terms of determining what type it is, more primitive meteorites, these are a type that still have textures and mineralogy that were inherited from condensation and accretion in the solar nebula, that's where individual mineral grains formed out of a gas that -- that was the nebula before the planets were around. And -- and then they glomerate together, these mineral grains, and in the -- in the solar nebula, the dust grains banged, you know, got melted into little, tiny objects which we call chondrules. So, these typical textures are plainly evident to the human eye, even without a microscope. But, you know, with a very low-power microscope you can see them quite easily. Most meteorites, especially primitive ones, contain iron metal, it's actually iron nickel metal. You know, you don't find that on earth except when humans have been involved in -- in smelting iron ore. But so iron metal in a -- in a rock is kind of an indicator that it's quite likely from outer space. Very few occurrences on earth of native metal in a rock. And then, as I said, in the dust in the solar nebula, went through periods of melting and formation of these little, round globules of basically melt globules, which we call chondrules, and -- and from that, we get the name chondrite for these primitive rocks. Well, those stand out in, you know, if you break open a rock, depending on -- on the type, you know, you can see those quite easily, and -- and that's a key. Host: And these have never -- they've been in space for all of time, right? They were formed in space and traveling through space, they've never -- they're not like from another planet or another, like, chipped off another...? Dr. Duck Mittlefehldt: Well, most...no, actually, all meteorites, the only way we get meteorites is for bad things to happen in the asteroid belt. Most meteorites are from asteroids, and when they collide, little fragments get knocked off, and it's -- it's from these fragments that we get meteorites. So they were originally on much larger bodies, I mean, much larger meaning asteroid size, not planet size. Host: Okay. Dr. Duck Mittlefehldt: And they were broken up and then distributed to the earth. You know, one of the, sorry, I'm going to -- I'm going to sort of go back into -- and get into my way back machine and go back to when I was a grad student. Host: Please do! Dr. Duck Mittlefehldt: When I -- you know, when I first started learning about meteorites, one of the mysteries at the time was there was a group of chondrite meteorites called the L chondrites, L was just the name, you know, the -- the name applied to them. That had ages on the order of 500 million years, and this was really odd, because all meteorites are about four and a half billion years old. Well these, they -- they -- these meteorites were originally about four and a half million -- billion years old, but were somehow affected by an event that reset the ages about 500 million years ago. Host: Woah. Dr. Duck Mittlefehldt: And so, you know, this was, you know, just kind of an anomaly. We knew something bad had happened to an asteroid then, about that time, well, fast forward to, I think the 90's, a Swedish geologist started finding in terrestrial sediments fossil meteorites. And, you know, all that's left is a few mineral grains. You -- you can tell, they were found in fine grain limestone, you know, formed on an ocean floor, and all that you could see was this halo of odd stuff, please a few mineral grains that remained from the original meteorite. Well, you know, this guy, and his compadres, studied these mineral grains and they -- they found out they were from the same type of meteorite as these chondrites that were about 500 million years old, and they were in layers in the rock of the earth that were about that age. So, sometime, 500 million years ago, you know, a couple of asteroids collided, and a whole rain of meteorites of this type hit the earth at about, you know, within a few million years when that occurred, and we can find them now. This layer in Sweden that's just chock full of these fossil meteorites. And, you know, to me, that's one of these really neat kind of science stories. Where everything starts tying together. And then to get even further, astronomers looking at what they call asteroid families, so they -- they find an asteroid, they find a whole bunch in orbits similar to it, spectroscopically, they all look to be about the same, and so they -- they figure out, well, these are all, you know, fragments of something that broke apart. Well, they found an asteroid that they figure, you know, based on the spectroscopy, it could be this type of, you know, that formed these L chondrites, and the -- they calculate the age of the family based on dispersion of the fragments, and it's about 500 million years. So, you know, between, you know, meteorite scientists, terrestrial geologists, and astronomers, we -- we've kind of got a neat picture of somehow, you know, about the time of dawn of -- of multicellular life on earth, two asteroids smashed together, and rained down on the earth, and we're still finding fragments coming down to earth now that we can confidently date when this happened in terrestrial laboratories. It's just kind of one of these things that, you know, I find fascinating! Host: [Laughing] I find it -- I mean, a lot of this is over my head, because I don't have the same background as you, but I just find it fascinating that you can look at these rocks and -- and get a story, get a story out of it, you know? Like the story of two asteroids around the time that cellular life was developing coming down to earth and raining down in these locations and telling their story, that's fantastic! Dr. Duck Mittlefehldt: Yeah, and multicellular. So this is when... Host: Multicellular. Dr. Duck Mittlefehldt: This is when, you know, fossils, shortly after the time when fossils started becoming really abundant in the terrestrial record. Host: Wow. Dr. Duck Mittlefehldt: So, yeah, it's just a neat story, and, you know, basically I think that's what got me into geology, originally, was, you know, all you've got is -- is a rock on the surface and somehow you can, you know, if you're smart enough and -- and do the right work, you can start to piece together an entire story of what the earth was like at that time, and so, you know, that's kind of what drew me into geology. Host: That's fantastic. I love it! Especially from -- from my background, marketing and journalistic sort of background, the story telling aspect is just fascinating to me. And that's kind of like, that, you know, the title of this episode is going to be, Infamous Meteorites, and that's kind of like what I really wanted to dive into is, you know, we've talked about where you're finding these meteorites, and then what you're doing with then, you're actually cracking them open and studying them, but then what are you finding? What are you finding inside of these meteorites? What stories? Dr. Duck Mittlefehldt: Yeah. Well, exactly! Host: Yeah, so, you know, one of the ones that I know that was brought to my attention was one of them called Allan Hills, and -- I'm going to -- is it 84001, or do you call it by something else? Dr. Duck Mittlefehldt: No, I call it that. Host: 84001? Okay. Dr. Duck Mittlefehldt: Sometimes it's simply referred to as that rock. Host: [Laughing] Because it's that infamous, huh? Wow! Alright, so what's the story behind -- behind this rock? Dr. Duck Mittlefehldt: Okay, so, this came -- this was found in Antarctica in 1984. And it -- it's [pause] -- it was originally classified as a -- as a type of asteroidal igneous rock that I, at the time, I was studying those -- those types of rocks. You know, my -- my background is heavily-weighted towards an interest in magnetic processes on the earth, the moon, Mars, and asteroids, and -- and so that's why this one was particularly of interest to me. So, I was studying that, along with a bunch of others, that were thought to be basically the same classification of rock, and, unfortunately, Allan Hill's had some puzzling features in it that were -- were a little bit off normal for -- for that rock type. But not so much so that I -- I really stayed up at night worrying about it. Host: [Gary laughing] Dr. Duck Mittlefehldt: And so I wrote a paper on -- on this group of rocks, finally, and sent it in, and one of the reviewers said, well, you know, you point out that there's this anomaly in this rock, and you really ought to try and chase down why it's -- what's going on there, why it's different. And, you know, being a -- a moderately good scientist, I said, okay. I, you know, he has pointed out, it's a problem, I knew it was a problem, but now I've really got to do something about it. So I started working at it, and, honestly, I -- I could not find out what was wrong with this particular rock. It -- it -- there was one mineral phase in it just did not match what anyone would expect for the class. Quite by chance, I got another sample of that rock for another reason. And but it really wasn't the sample I had asked for. So there was as mixup in the thin section. So a thin section is a very thin slice of a rock, it's about 30 microns thick, doubly polished on both sides, and it's used by people who look through microscopes to look at the minerals and textures in a rock, and then you can put that section into an electron microprobe and actually do analyses of the mineral phases in it. Host: Wow. Dr. Duck Mittlefehldt: And so I was -- that's what I was interested in. And this particular rock, which I thought I had, I was interested in the composition of sulfide phases in the rock. So I put the sample in the electron microprobe without actually looking at it in the microscope first, because I had seen this rock before, I knew what it was like, I knew what to expect, I just went straight to the electron microprobe, which actually probably was good because I may have turned the rock in and asked for a different one otherwise. But I'm getting -- I'm looking at it in the microprobe, looking for the mineral phases I'm looking for, and they just really aren't there in the abundance that I expected. Finally I found a grain and I'm -- I'm banging at it with the electron beam, collecting compositions, and the compositions weren't making sense. I was expecting it to be, so I was looking for sulfide phases, so I was expecting to have iron monosulfide, so one iron, one sulfur atom, and the composition that was coming out just was not right. And I checked the calibration, the calibration was perfect, so what's going on? I was looking at the data, not in atoms, but in mass, so weight percent. So when I converted it to atoms, I realized I had two sulfur atoms for every iron atom instead of one, and that's when it hit me what was wrong with this rock. I then backed off, looked at the -- looked at the texture in more detail in the electron microprobe, and realized I had a sample of Allan Hill's, not the meteorite that I thought I had, and I knew which type of rocks had pyrate, the iron disulfide, instead of the iron monosulfide, and I knew those were martian rocks. And so, you know, it was -- it was probably the most satisfying moment I've ever had in my life, excluding when my children were born, and -- and when I got married [Gary laughing], and if my wife listens to this, I hope she hears that, was, you know, suddenly it dawned on me that this was a martian rock that was totally unlike any other martian rock, except the key minerals were in it, and so, you know, it was just one of these aha moments that -- that you live for. And, you know, it was just so much fun. Host: Amazing. Dr. Duck Mittlefehldt: I tell you. Host: So what were those -- the key minerals? What -- what story did they tell? Dr. Duck Mittlefehldt: So the key was because it had the iron disulfide pyrate instead of the iron monosulfide troite, I knew it was martian, and it was a rock type not known amongst the martian meteorites. So what it meant was we had a new type of martian rock that was going to tell us even more about the geologic evolution of Mars then we already knew. And, you know, all of this hit me within like a fraction of a second when I realized what it was. Host: Wow! Dr. Duck Mittlefehldt: So, I mean, I immediately recognized it, it was an, you know, important meteorite. And that it would tell us big things, and, in fact, you know, it has opened up a whole host of, you know, basically this rock ultimately became a founding member of what you might consider astrobiology, and that came when my colleagues here at Johnson Space Center, Dave McKay, Edward Gibson, and Kathie Thomas and now Simon Clemett is at it, and then there were Simon's dissertation advisors, Stanford was on the paper and several other people, you know, they -- they proposed that a certain both mineralogical and compositional and textural objects in this rock were possibly signs of microscopic life that existed on Mars at one point. Host: Wow. Dr. Duck Mittlefehldt: And, you know, to some extent, then this really allowed the whole discipline of astrobiology to blossom because suddenly we had to figure out, you know, what -- how do we understand, how can we possibly search for life and other objects, other planets, you know, what do we need to look for? Because we're used to looking for life on earth, you know, it's -- it's simple. Just walking over here, I, you know, I had to wait while an opossum walked past me in front of, on the walkway. You know, life is everywhere on earth, whereas on Mars, you know, maybe it's not everywhere, and if it was there, how are we going to tell that it was there? What -- what do we need to do? So I would say the import of Allan Hill's not so much that it was hypothesized that life -- fossils of life are in that rock, but that it caused scientists to really take a much more rigorous look at how they will search for life other places of the universe. Host: Wow. And that's -- that's kind of, you know, like you said, the birth, maybe not the birth, but really the blossoming, and that was the word you used of, of astrobiology, life forming outside of earth. That's just a wild concept. How is that even possible? Dr. Duck Mittlefehldt: Yeah, and, you know, the other thing is it did, it was a strong impetus to driving NASA's Mars exploration program, you know, it is -- - a lot of it is geared towards finding evidence for habitability locations on Mars, and, ultimately, you know, from locations where we think there may have been a chance for life, you know, bringing back or -- or studying in situ samples for possible evidence of microbial or -- or larger life on Mars. Host: Yeah, and you said you were, before we started recording, you said you actually were working with Opportunity too, one of the rovers on Mars. Dr. Duck Mittlefehldt: Yeah. I, in 2005, I got attached to the Mars Exploration Rover mission. At the time, we had two rovers going, one Spirit in Gusev Crater, and the other, Opportunity, in Meridiani Planum. Subsequently, Spirit froze to death one winter. Basically, so Spirit lost mobility of one of its wheels, so we were driving backwards, dragging one of the front wheels like a boat anchor through the soil... Host: Oh, man. Dr. Duck Mittlefehldt: And we, you know, the Rover drivers and scientists are very careful. We drove over an area that looked like it was going to be solid, trafficable ground, but it turned out there was a basically a hardpan; layer on top of soil hardpan is kind of an indurated layer that's a little bit stiffer, so it didn't look like it was, you know, loose sand, but it turns out we broke through and got mired in a deep sandpit, basically, and we were unable to extract the rover from the sand, in spite of heroic efforts by the engineers, the Rover drivers at JPL, and the solar panel was tilted at a bad angle for, you know, the oncoming winter sun. So when the sun started getting lower and lower, relative to the tile of the -- of the solar panel, we -- we simply were not getting enough power to keep the rover going and although we tried to contact it again after that winter, we never heard from it again, so it basically just froze to death on Mars. Host: Oh, man, but is Opportunity its twin? Is it the... Dr. Duck Mittlefehldt: Yep, Opportunity is it's twin. Host: And that one's still going, right? Dr. Duck Mittlefehldt: And that one's still going. We're now so -- we're not -- what day is today? Host: The 8th. Yeah, we're now about two weeks away from the anniversary, the 16the anniversary of landing on Mars for Opportunity. Host: 14 years? Wow! Dr. Duck Mittlefehldt: It's still going strong, and we are still actively exploring the geology of Meridiani Planum. We don't have all the instruments we had when we landed, but we're still making great scientific discoveries, even with the limited rover ability. Host: How about that? So how is -- how was, you know, working with a rover on Mars different from looking at meteorites? Maybe even martian meteorites, like the Allan Hills, here on earth? How is that different? Well, so, you know, here on earth, I have the luxury of taking a sample into the lab and -- and using state-of-the-art scientific equipment to -- to tease out, tease out its story. On Mars, we have cameras that we can use to image the terrain. So right away, textures, and we have a microscopic camera, so textures allow us to, you know, make inferences about what the rock -- how the rock might have been formed. We have a camera with 13 color filters on it, so we can do some limited spectroscopy of the rock that helps us compare a limited set of mineralogical variations in the rocks, and then we have the alpha particle x-ray spectrometer, which allows us to do bulk compositions of surfaces. So, between them, we -- we can -- we can get a fairly good handle of the mineral -- well, mostly the textures and bulk composition, and, to some extent, neurology of a rock, and that helps us understand what processes might have formed the rock altogether. And, you know, to some extent, where Opportunity is a high-tech version of a 19th century terrestrial geologist. [Gary laughing] But, you know, the, obviously the spectrometer is better than what they had in the 19th century, and the chemical composition is as -- as good as we could do then and actually better for many elements, but we're still not at the cutting edge, as you -- as you could do if you had a, you know, a mobile laboratory up on Mars. Host: Yeah, definitely. And that's kind of your -- your trade-off, right? Is like, here, you know, you can bring into a lab with all the latest equipment and -- and study these meteorites, but, like you said before, like there's a certain amount of contamination that's going on with just the fact that a meteorite has come through the atmosphere and hit the -- hit the -- surface of the earth, you know, you have to deal with that, but then you have limited instruments right there on -- on Mars. So, I guess you just kind of have these tradeoffs [laughing]. Dr. Duck Mittlefehldt: Yep. Host: So another one that you mentioned, another infamous meteorite, was one called Orgueil, and that's one -- that one's much earlier than the Allan Hills one, right? Dr. Duck Mittlefehldt: So Orgueil fell in France in 1864, if I -- if I remember right, and what's key here is it's a -- it's a very primitive type of meteorite. It's a carbonaceous chondrite. The -- the two letter name for it is a CI carbonate -- chondrite. These are amongst the most primitive materials, primitive meteorites that we have for study. They're bulk compositions, basically are identical to what we see for the photosphere of the sun, excluding the most volatile elements like -- like helium, hydrogen, and oxygen and so forth, but if you could take the sun, you know, a cubic kilometer of the sun and condense out all the condensable matter, it would -- the composition would be very much like a carbonaceous, CI carbonaceous chondrite. So, these have always been the touchstone for understanding the chemical evolution of the solar system. They are our -- our basis for seeing who has varied from the original composition. But they're highly-altered, so they are almost completely made up of clays and other low-temperature alteration phases. So the original high-temperature phases have been replaced. So, at some point, these things were altered by water in their parent asteroid to the point where all that's left is -- is basically clay. This makes them [sigh] -- this made Orgueil susceptible to nefarious individual, tempting to prove something, what don't know, because we don't know who that individual was, but, you know, I would call Orgueil the Piltdown Man of meteorites. So Piltdown Man was -- was this fake fossil made in about 1912 I think to look like it had some of the attributes of an ape, but some of the attributes of a modern human, because someone that that's the way human evolution went, and they wanted to show that we had fossils that fit in within that theory. Well, Orgueil, at some point, was broken open, and it turns out, because this is clay, you can -- if you get it good and wet, you can kind of break it open like clay, and then they had stuffed in terrestrial seeds and plant fragments and coal, and then put it back together, and coated the outside with glue to make it look like it still had the fusion crust on it. Host: Oh my gosh! Dr. Duck Mittlefehldt: And then this sample was sealed in a bell jar in a museum from 1864, so apparently it happened very early, we don't know who did it, or why, you know, what were they trying to accomplish by this? Because it was going to be sealed in a bell jar, you know, did they think someone was going to then take it out and look at it, I don't know, but this -- this came to light in 1960's then. Host: Oh! Dr. Duck Mittlefehldt: And so, a well-known meteoriticist, by the name of Ed Anders, very famous, very smart man, he led a study that was published 100 years later, in 1964 in science, where he uncovered, you know, all of this forensic meteoritic work where he showed that, you know, the seeds were, you know, terrestrial seeds, the coal fragments were in there, that glue had been used to put it back together and make it look like it was whole, and -- and all of this, and -- and so that's why, you know, this is an infamous -- infamous meteorite for those who are in the know. Most people won't have heard of it, but, you know, like I said, it's kind of the Piltdown Man of meteoritics. Host: Wow! Dr. Duck Mittlefehldt: So someone had an agenda, they wanted -- they, for some reason, they wanted to show that life could form on an asteroid or -- or in space, or something, I don't know, but, obviously, they had -- they had some agenda when they did this. Host: Yeah, I know, but seeds and glue are not really a good way to convince people [laughter]. Dr. Duck Mittlefehldt: No. You know, back in the, you know, mid-19th century, you know, had it been opened up and studied then, maybe it would have caused quite a furor, but, as far as I know, this was only discovered in, you know, a century later. Host: Wow! A hundred years of people thinking this is some kind of like capsule of extraterrestrial life, how about that? So, you know, all of these kind of tell a story and, unfortunately, some of them, this [laughing] -- this particular one is a little bit of a lie, but, you know, we are cracking these open to search for evidence of -- of whatever we can find, right? Maybe -- maybe the formation of a planet, maybe the formation of solar system, maybe the formation of life. So, you know, what, in a perfect world, I guess, what would you like to do -- what would you like to study? What would you like to see and do to really maximize what you can find about learning more about our solar system and about life in the universe Dr. Duck Mittlefehldt: Well, I mean, that -- that's kind of a difficult question for a scientist to answer, because, you know, truth be told, we're all paid to pursue our hobbies, and so we all have our own hobby horses. So, as I -- as I mentioned, you know, my particular interests are in igneous processes, I, you know, on the earth, moon, Mars, asteroids, I -- I like magmatic rocks, and, you know, I couldn't tell you why, it's just the way I am [Gary laughing]. So, one of the things -- one of the things that's very curious about asteroidal igneous rocks is that asteroids were melted very early in the solar system, probably within a couple million years of the formation of the earliest-known solids in the solar system. So something had to heat up relatively small objects, maybe a few hundred kilometers, you know, 200 miles in -- or in radius, something like that, to the point where they were melted and then cooled down and then they completely shut off after that. So, it was a very, very intense heat source that acted early, died out, and then never came back. You know, we think we know what -- what caused this, but there, you know, and so the -- the leading contender is radioactive heating by a very short-lived isotope of aluminum. It has a half-life of about 730 million years, and so, and aluminum is a -- is a major element in rocks, so, if you -- if you accumulate an asteroid early enough, when there's this aluminum-27 still alive, you've, you know, -- you've then encapsulated a very potent heat source inside that rock. And so that's what we think happened, but, still, you know, we can admit, as scientists, we can imagine this process going on, but geology is always much more complicated than our imaginations. So there are things that I don't understand, things that, as far as I know, no one really understands about how asteroids went from being primitive objects that accumulated from minerals formed in the solar nebula to basically a molten ball that then crystallized out igneous magmatic rocks, similar to what we see on earth. I would desperately like to get, you know, be able to find out more about how -- what was going on, you know, what have we missed, because we, you know, we tend to think of things in -- in the simplest terms, you know, it was heated up, melted, crystallized, that's it, well, we know that -- that's not all the story. Host: Yeah. Dr. Duck Mittlefehldt: And I think all meteoriticists have, in the back of their minds, for their particular hobby horses, just things they don't quite understand. They know the -- the broader picture, but what are the finer details that went into -- to this. We -- we know we've got the basic story, but what are, you know, all the chapter and verse that go into this basic story? Host: Wow. Dr. Duck Mittlefehldt: So, you know, that's what drives me, and it's all -- it's all a matter of, you know, learning something new that -- that, you know, pushes forth human knowledge. You know, what I do is -- is nowhere near applied science. It's pure basic science. So I can't -- I can't talk to someone and say, you know, tomorrow, you're going to be able to have a better life because of what I do, only if, you know, unless you think a better life means knowing more [Gary laughing]. But you never know, because, in -- in general, a large fraction of basic research ultimately does find an application. Right now, I don't know what that application might be, but I won't say there's never going to be some application for what I do, but, for me, it's -- it's this sense of learning something that -- that drives me. Host: Yeah. Why learn if you don't think it's going to end up, you know, giving you a better life. I mean, honestly, like, you know, learning things kind of helps you understand things, helps things come together, to me, that makes me pretty happy. So I could see that, you know, better understanding, giving me a better life. Dr. Duck Mittlefehldt: Yeah, well, I mean, you know, humans have always been curious, and, you know, I suspect the reason we're curious is because it's beneficial for survival, because, you know, when -- when you're out on the savannah hunting lions, or hunting gazelles, if you see something moving the weeds over there, you know, okay, is that a gazelle or is that a lion about to eat me instead? So, you know, humans are geared to being curious about their environment, because it's a survival mechanism. Host: Yeah. Dr. Duck Mittlefehldt: And, for scientists, we have now transposed that, you know, away from worrying about whether we're going to be eaten to just, you know, a broad knowledge in general. Host: [Laughing] Well, I think last time we sat down with Dr. Burton, he said, he kept talking about this time machine, how easy it would be -- how nice it would be to just kind of hop in a time machine, watch these processes take place, and be like, ah [snapping fingers], that's how -- that's how it takes place. I mean, and then there's whole philosophical idea of, well, is that going to alter the universe if you go back in time and watch these things? So, you know, that was another tangient we could have gone on and we didn't, but [laughter], but it would be nice to, you know, for the, you know, to improve our knowledge a little bit of how all this stuff works and comes together. Alright, so, Duck, I think -- I think that about wraps it up for today. So, thank you so much for coming on the podcast and kind of... Dr. Duck Mittlefehldt: It's been a pleasure. I hope I've imparted something that makes sense to the listeners and -- and that they will find interesting. Host: It's actually you know, you know, we're talking about rocks, if you think about it, but it's absolutely fascinating, what you can found and the stories behind these rocks and what they tell you about the universe, and even just your trips to Antarctica are pretty fascinating as well, so, again, thanks so much for coming on and telling the stories of these beautiful rocks and your trips to Antarctica, and, yeah, hopefully we'll -- we'll find some cool evidence of life or, you know, you'll find that key ingredient as to why, you know, the asteroids did what they did. Dr. Duck Mittlefehldt: Yeah, well, I hope so, and thank you very much for the invite! Host: Absolutely. [ Music & Radio Transmissions ] Hey, thanks for sticking around. So, today, we talked with Dr. Duck Mittlefehldt about some of the cooler, infamous meteorites that have been discovered throughout the years, and then some interesting stories about Antarctica and how he's finding them, it's really a cool process, and he works with the ANSMET, it's the Antarctic Search for Meteorites. So if you want to learn more about ANSMET and some of the adventures that are going on in Antarctica, and some of the curious findings in these meteorites, especially some that may or may not be life, it turns out there was some, you know, fake meteorites at the end of there, which is kind of disappointing, but that's okay. You can go to ares.jsc.nasa.gov to get the full scoop on all of these cool meteorites, and -- and you can learn how to get your hands on one of these meteorite samples to study them. If you go to social media on the NASA Johnson Space Center accounts, or if you go to ARES, or astromaterials, NASA astromaterials, we got pages on Facebook, Twitter, and Instagram where we like to share these stories, just use the hashtag, ask NASA, on -- on your favorite platform to submit an idea, or if you have a question about meteorites, or if you want to submit a new topic for the show, to make sure to mention it's for, Houston, We Have A Podcast. So this podcast was recorded on January 8th, 2018. Thanks to Alex Perryman, Greg Wiseman, Tracy Calhoun, and Jenny Knots, and thanks again to Dr. Duck Mittlefehldt for coming on the show! We'll be back next week!