PREFACE 12th International Workshop on Slow Positron Beam Techniques
NASA Astrophysics Data System (ADS)
Buckman, Stephen; Sullivan, James; White, Ronald
2011-01-01
Preface These proceedings arose from the 12th International Workshop on Slow Positron Beam Techniques (SLOPOS12), which was held on Magnetic Island, North Queensland, Australia, between 1-6th August 2010. Meetings in the SLOPOS series are held (roughly) every three years and have now been held on (almost) all continents, indicating the truly international nature of the field. SLOPOS12 marked the second time that the Workshop had been held in the southern hemisphere, and the first time in Australia. SLOPOS12 attracted 122 delegates from 16 countries. Most encouraging was the attendance of 28 student delegates, and that about half of the overall delegates were early career researchers - a good sign for the future of our field. We also enjoyed the company of more than a dozen partners and families of delegates. In a slight departure from previous SLOPOS meetings, the International Advisory Committee approved a broader scope of scientific topics for inclusion in the program for the 2010 Workshop. This broader scope was intended to capture the applications of positrons in atomic, molecular and biomedical areas and was encapsulated in the byeline for SLOPOS-12: The 12th International Workshop on Slow Positron Beam Techniques for Solids, Surfaces, Atoms and Molecules. The scientific and social program for the meeting ran over 6 days with delegates gathering on Sunday August 1st and departing on August 6th. The scientific program included plenary, invited, contributed and student lectures, the latter being the subject of a student prize. In all there were 53 oral presentations during the week. There were also two poster sessions, with 63 posters exhibited, and a prize was awarded for the best poster by a student delegate. The standard of the student presentations, both oral and posters, was outstanding, so much so that the judging panel recommended an additional number of prizes be awarded. Topics that were the focus of invited presentations and contributed papers at SLOPOS-12 included: Positron Interactions with Surfaces Positron Beam and Detector Technology Positron Interactions with Atoms and Molecules Positronium Science Defects and Vacancies in Materials Porosity and Open Volume in Materials Antimatter in Biomedical Science Anti-hydrogen Studies Positron Transport Annihilation On a sad note, delegates paid tribute to the contributions of one of our colleagues, Chris Beling, who tragically passed away shortly before the meeting. Chris' contributions to positron science and to the education of young scientists were noted in a number of the invited presentations. It is an honour for our community to begin these proceedings with a short tribute to Chris' life by Professor Paul Coleman. The Workshop could not have occurred without the generous support of our sponsors: The ARC Centre for Antimatter-Matter Studies, The Australian National University, Flinders University, James Cook University, The Institute of Physics (UK) and the Australian Government's Department of Innovation, Industry, Science and Research. It would also not have been possible without the hard work of the Local and International Organising Committees and the friendly and efficient staff at the All Seasons Resort, Magnetic Island. We are most grateful for the on-site assistance of Gillian Drew, the CAMS student and postdoc team, the financial wizardry of Chris Kalos, and the post-Workshop editorial assistance of Julia Wee and Adam Edwards. Finally we would like to thank all of the attendees at SLOPOS12 for their scientific contributions to the Workshop, and for the warm spirit of engagement which characterised the scientific discussions and social occasions. SLOPOS13 will be held in Germany in 2013 and we all look forward to the occasion. Stephen Buckman, James Sullivan and Ronald White(Guest Editors) Local Organising CommitteeInternational Committee Stephen Buckman (Chair, ANU, Canberra)G Amarendra (India) James Sullivan (Secretary, ANU, Canberra)M-F Barthe (France) Ronald White (JCU, Townsville)C Beling (Hong Kong) Jim Williams (UWA, Perth)R Brusa (Italy) Suzanne Smith (ANSTO, Sydney)P Coleman (UK) Igor Bray (Curtin U., Perth)C Corbel (France) Casten Makochekanwa (ANU, Canberra)M Fujinami (Japan) Michael Went (ANU, Canberra)R Krause-Rehberg (Germany) Adric Jones (ANU, Canberra)K Lynn (USA) Peter Caradonna (ANU, Canberra)H Schut (Netherlands) Ryan Weed (ANU, Canberra)P Simpson (Canada) Jason Roberts (ANU, Canberra)R Suzuki (Japan) Josh Machacek (ANU, Canberra)F Tuomisto (Finland) A Weiss (USA) SLOPOS photo SLOPOS-12 Delegates, 1-6 August 2010, Magnetic Island, Australia SPONSORS SLOPOS sponsors
Kim, Sarang; Cherbuin, Nicolas; Anstey, Kaarin J
2016-06-01
To assess the reliability of short versions of the Australian National University Alzheimer's Disease Risk Index (ANU-ADRI). A short form of the ANU-ADRI (ANU-ADRI-SF) was developed by assessing risk and protective factors with single questions where possible and with short forms of sub-questionnaires where available. The tick box form of the ANU-ADRI (ANU-ADRI-TB) was developed with unique questions for each risk and protective factor for Alzheimer's disease. The short versions were evaluated in an independent community sample of 504 participants with a mean age of 45.01 (SD = 14.85, range = 18-81). The short versions demonstrated high reliabilities when compared with the ANU-ADRI. However, the proportion of misclassification was high for some risk factors and particularly for the ANU-ADRI-TB. The ANU-ADRI-SF may be considered if less reliable questions from the ANU-ADRI-SF can be replaced with more reliable questions from the ANU-ADRI for risk/protective factors with high misclassification.
Arabidopsis ANGULATA10 is required for thylakoid biogenesis and mesophyll development
Micol, José Luis
2014-01-01
The chloroplasts of land plants contain internal membrane systems, the thylakoids, which are arranged in stacks called grana. Because grana have not been found in Cyanobacteria, the evolutionary origin of genes controlling the structural and functional diversification of thylakoidal membranes in land plants remains unclear. The angulata10-1 (anu10-1) mutant, which exhibits pale-green rosettes, reduced growth, and deficient leaf lateral expansion, resulting in the presence of prominent marginal teeth, was isolated. Palisade cells in anu10-1 are larger and less packed than in the wild type, giving rise to large intercellular spaces. The ANU10 gene encodes a protein of unknown function that localizes to both chloroplasts and amyloplasts. In chloroplasts, ANU10 associates with thylakoidal membranes. Mutant anu10-1 chloroplasts accumulate H2O2, and have reduced levels of chlorophyll and carotenoids. Moreover, these chloroplasts are small and abnormally shaped, thylakoidal membranes are less abundant, and their grana are absent due to impaired thylakoid stacking in the anu10-1 mutant. Because the trimeric light-harvesting complex II (LHCII) has been reported to be required for thylakoid stacking, its levels were determined in anu10-1 thylakoids and they were found to be reduced. Together, the data point to a requirement for ANU10 for chloroplast and mesophyll development. PMID:24663344
Australian National University Science Extension Day
ERIC Educational Resources Information Center
Fletcher, Sarah
2016-01-01
The first Australian National University (ANU) Science Extension Day was held on September 8, 2015. The ANU Science Extension Day is a project that was initiated by Theodore Primary School (ACT) and developed by Theodore Primary, Calwell High School, Science Educators Association of the ACT (SEA*ACT), and the ANU. The project was developed with a…
Post-Doctoral Fellowship for Merton S. Krause. Final Report.
ERIC Educational Resources Information Center
Jackson, Philip W.
The final quarter of Krause's fellowship year was spent in completing his interviews with political socialization researchers in the eastern United States and his work on methodological problems. Krause also completed a long essay on the nature and implications of the "matrix perspective" for research planning, pursued his study of measurement…
Operator-sum representation for bosonic Gaussian channels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ivan, J. Solomon; Sabapathy, Krishna Kumar; Simon, R.
2011-10-15
Operator-sum or Kraus representations for single-mode bosonic Gaussian channels are developed, and several of their consequences explored. The fact that the two-mode metaplectic operators acting as unitary purification of these channels do not, in their canonical form, mix the position and momentum variables is exploited to present a procedure which applies uniformly to all families in the Holevo classification. In this procedure the Kraus operators of every quantum-limited Gaussian channel can be simply read off from the matrix elements of a corresponding metaplectic operator. Kraus operators are employed to bring out, in the Fock basis, the manner in which themore » antilinear, unphysical matrix transposition map when accompanied by injection of a threshold classical noise becomes a physical channel, denoted D({kappa}) in the Holevo classification. The matrix transposition channels D({kappa}), D({kappa}{sup -1}) turn out to be a dual pair in the sense that their Kraus operators are related by the adjoint operation. The amplifier channel with amplification factor {kappa} and the beam-splitter channel with attenuation factor {kappa}{sup -1} turn out to be mutually dual in the same sense. The action of the quantum-limited attenuator and amplifier channels as simply scaling maps on suitable quasiprobabilities in phase space is examined in the Kraus picture. Consideration of cumulants is used to examine the issue of fixed points. The semigroup property of the amplifier and attenuator families leads in both cases to a Zeno-like effect arising as a consequence of interrupted evolution. In the cases of entanglement-breaking channels a description in terms of rank 1 Kraus operators is shown to emerge quite simply. In contradistinction, it is shown that there is not even one finite rank operator in the entire linear span of Kraus operators of the quantum-limited amplifier or attenuator families, an assertion far stronger than the statement that these are not entanglement breaking channels. A characterization of extremality in terms of Kraus operators, originally due to Choi, is employed to show that all quantum-limited Gaussian channels are extremal. The fact that almost every noisy Gaussian channel can be realized as a product of a pair of quantum-limited channels is used to construct a discrete set of linearly independent Kraus operators for these noisy Gaussian channels, including the classical noise channel, and these Kraus operators have a particularly simple structure.« less
Kraus Operators for a Pair of Interacting Qubits: a Case Study
NASA Astrophysics Data System (ADS)
Arsenijević, M.; Jeknić-Dugić, J.; Dugić, M.
2018-04-01
The Kraus form of the completely positive dynamical maps is appealing from the mathematical and the point of the diverse applications of the open quantum systems theory. Unfortunately, the Kraus operators are poorly known for the two-qubit processes. In this paper, we derive the Kraus operators for a pair of interacting qubits, while the strength of the interaction is arbitrary. One of the qubits is subjected to the x-projection spin measurement. The obtained results are applied to calculate the dynamics of the entanglement in the qubits system. We obtain the loss of the correlations in the finite time interval; the stronger the inter-qubit interaction, the longer lasting entanglement in the system.
Kraus Operators for a Pair of Interacting Qubits: a Case Study
NASA Astrophysics Data System (ADS)
Arsenijević, M.; Jeknić-Dugić, J.; Dugić, M.
2018-06-01
The Kraus form of the completely positive dynamical maps is appealing from the mathematical and the point of the diverse applications of the open quantum systems theory. Unfortunately, the Kraus operators are poorly known for the two-qubit processes. In this paper, we derive the Kraus operators for a pair of interacting qubits, while the strength of the interaction is arbitrary. One of the qubits is subjected to the x-projection spin measurement. The obtained results are applied to calculate the dynamics of the entanglement in the qubits system. We obtain the loss of the correlations in the finite time interval; the stronger the inter-qubit interaction, the longer lasting entanglement in the system.
Continued-fraction representation of the Kraus map for non-Markovian reservoir damping
NASA Astrophysics Data System (ADS)
van Wonderen, A. J.; Suttorp, L. G.
2018-04-01
Quantum dissipation is studied for a discrete system that linearly interacts with a reservoir of harmonic oscillators at thermal equilibrium. Initial correlations between system and reservoir are assumed to be absent. The dissipative dynamics as determined by the unitary evolution of system and reservoir is described by a Kraus map consisting of an infinite number of matrices. For all Laplace-transformed Kraus matrices exact solutions are constructed in terms of continued fractions that depend on the pair correlation functions of the reservoir. By performing factorizations in the Kraus map a perturbation theory is set up that conserves in arbitrary perturbative order both positivity and probability of the density matrix. The latter is determined by an integral equation for a bitemporal matrix and a finite hierarchy for Kraus matrices. In the lowest perturbative order this hierarchy reduces to one equation for one Kraus matrix. Its solution is given by a continued fraction of a much simpler structure as compared to the non-perturbative case. In the lowest perturbative order our non-Markovian evolution equations are applied to the damped Jaynes–Cummings model. From the solution for the atomic density matrix it is found that the atom may remain in the state of maximum entropy for a significant time span that depends on the initial energy of the radiation field.
Searching for a Different Understanding of Operational Art
2016-05-26
that “hampered by 35 Bruce Menning, “Operational Art’s Origins,” in Historical Perspectives of the Operational Art, ed. Michael D. Krause and R. Cody...war or theater of 43 Clayton Newell, “Introduction,” in On Operational Art, ed. Clayton Newell and Michael Krause (Washington, DC: US Army Center of...Menning, Bruce. “Operational Art’s Origins.” In Historical Perspectives of the Operational Art, edited by Michael D. Krause and R. Cody Phillips, 3
Collisional Dynamics of the Rubidium 5(2)P Levels
1995-08-01
prepare the rubidium sample. This work established the cross-section for He collisions and bounded the cross-sections for Ne and Ar. Krause (49...continued the work by improving the measurement of the cross-sections and by adding the cross-sections for Kr, Xe and Rb collision partners. Krause ...number density of ,-r 1010 per cm 3 . This is an order of magnitude lower than the concentration reported by Krause (49) to prevent self trapping
1983-01-01
BLDGS 1,269 PHILLIPS SWAGER ASSOCIATES ILLINOIS ARMY A/E CONSTRUCTION /ADMIN 9 SVC BLDGS 174 QUINLIVIAN PIERIK KRAUSE ROBSON JV NEW YORK NAVY A/E...CONSTRUCTION /AIRFIELD & MSL FAC RANCORN WILDMAN & KRAUSE VIRGINIA NAVY A/E CONSTRUCTION /AIRFIELD & MSL FAC REED ALONZO B MASS ARMY A/E CONSTRUCTION...ARCHITECT/ENGINEER - GENERAL CONTRACTOR TOTAL OUADRA ENGINEERING INC ALASKA OCE ARCHITECT/ENGINEER - GENERAL QUINLIVAN PIERIK & KRAUSE MASS ARMY ARCHITECT
In the Middle of the Fight: An Assessment of Medium-Armored Forces in Past Military Operations
2008-01-01
U.S. World War II Tanks and Artillery, Iola, Wisc.: Krause Publications, 1994, pp. 15–33, 46–56; Roman Johann Jarymowycz, Tank Tactics: From...Colonel Michael Krause , believed “the army’s response in East Timor—weighted in favour of rapid deployability over firepower, pro- tection and close...Colonel Krause , however, indicated that he would have preferred to have had the Leopards in East Timor: [I]f it [the largely unopposed lodgements and
2007-06-01
Alexandra Krause , analyzing the EU’s role as an international actor in Africa, argues that the “policy of the EU towards sub-Saharan Africa – seen from a...Mwesiga Baregu and Christopher Landsberg (London, Boulder: Lynne Rienner Publishers, 2003), 301-316. 3 Alexandra Krause , “The European Union’s Africa...Intervening Variables,” in Krasner, ed. International Regimes, Ithaca: Cornell University Press, 1983. Krause , Alexandra. “Die EU als
Goldman, M E; Pearce, L A; Hart, R G; Zabalgoitia, M; Asinger, R W; Safford, R; Halperin, J L
1999-12-01
Stroke associated with atrial fibrillation (AF) is mainly due to embolism of thrombus formed during stasis of blood in the left atrial appendage (LAA). Pathophysiologic correlates of appendage flow velocity as assessed by transesophageal echocardiography (TEE) in patients with AF have not been defined. To evaluate the hypothesis that reduced velocity is associated with spontaneous echocardiographic contrast and thrombus in the LAA and with clinical embolic events, we measured LAA flow velocity by TEE in 721 patients with nonvalvular AF entering the Stroke Prevention in Atrial Fibrillation (SPAF-III) study. Patient features, TEE findings, and subsequent cardioembolic events were correlated with velocity by multivariate analysis. Patients in AF during TEE displayed lower peak antegrade (emptying) flow velocity (Anu(p)) than those with intermittent AF in sinus rhythm during TEE (33 cm/s vs 61 cm/s, respectively, P <.0001). Anu(p) < 20 cm/s was associated with dense spontaneous echocardiographic contrast (P <.001), appendage thrombus (P <.01), and subsequent cardioembolic events (P <.01). Independent predictors of Anu(p) < 20 cm/s included age (P =.009), systolic blood pressure (P <.001), sustained AF (P =.01), ischemic heart disease (P =.01), and left atrial area (P =.04). Multivariate analysis found both Anu(p) <20 cm/s (relative risk 2.6, P =.02) and clinical risk factors (relative risk 3.3, P =.002) independently associated with LAA thrombus. LAA Anu(p) is reduced in AF and associated with spontaneous echocardiographic contrast, appendage thrombus, and cardioembolic stroke. Systolic hypertension and aortic atherosclerosis, independent clinical predictors of stroke in patients with AF, also correlated with LAA Anu(p). Our results support the role of reduced LAA Anu(p) in the generation of stasis, thrombus formation, and embolism in patients with AF, although other mechanisms also contribute to stroke.
NASA Astrophysics Data System (ADS)
Xiang-Guo, Meng; Ji-Suo, Wang; Hong-Yi, Fan; Cheng-Wei, Xia
2016-04-01
We solve the fermionic master equation for a thermal bath to obtain its explicit Kraus operator solutions via the fermionic state approach. The normalization condition of the Kraus operators is proved. The matrix representation for these solutions is obtained, which is incongruous with the result in the book completed by Nielsen and Chuang [Quantum Computation and Quantum Information, Cambridge University Press, 2000]. As especial cases, we also present the Kraus operator solutions to master equations for describing the amplitude-decay model and the diffusion process at finite temperature. Project supported by the National Natural Science Foundation of China (Grant No. 11347026), the Natural Science Foundation of Shandong Province, China (Grant Nos. ZR2013AM012 and ZR2012AM004), and the Research Fund for the Doctoral Program and Scientific Research Project of Liaocheng University, Shandong Province, China.
Bizzaro, Nicola; Villalta, Danilo; Giavarina, Davide; Tozzoli, Renato
2012-12-01
Methods to detect anti-nucleosome antibodies (ANuA) have been available for more than 10 years and the test has demonstrated its good sensitivity and high specificity in diagnosing systemic lupus erythematosus (SLE). Despite these data produced through clinical and laboratory research, the test is little used. To verify the diagnostic performance of methods for measuring ANuA and to compare them with those for anti-dsDNA antibodies. A systematic review of English and non-English articles using MEDLINE and EMBASE with the search terms "nucleosome", "chromatin", "anti-nucleosome antibodies" and "anti-chromatin antibodies". Additional studies were identified checking reference lists in the selected articles. We selected studies reporting on anti-nucleosome tests performed by quantitative immunoassays, on patients with SLE as the index disease (sensitivity) and a control group (specificity). A total of 610 titles were initially identified with the search strategy described. 548 publications were subsequently excluded based on abstract and title. Full-text review was undertaken as the next step on 62 publications providing data on anti-nucleosome testing; 25 articles were then excluded because they did not include either SLE patients or a control group, and 37 articles were selected for the metanalysis. Finally, a sub-metanalysis study was conducted on the 26 articles providing data on both ANuA and anti-dsDNA antibody assays in the same series of patients. Extraction of data from selected articles was performed by two authors independently, using predefined criteria: the number of patients with SLE as the index case, and the number of healthy or diseased controls; specification of the analytical method used to detect anti-nucleosome and anti-dsDNA antibodies; the cut-off used in the study; and the sensitivity and specificity of the assay. Demographic and clinical data on the population investigated (adults or children; lupus patients with or without nephritis; patients with active or inactive disease) were also recorded and analyzed in a separate evaluation. The systematic review and metanalysis showed that the overall sensitivity of the ANuA assay is 61% (confidence interval-CI, 60-62) and the specificity 94% (CI, 94-95). The overall positive likelihood ratio is 13.81 (CI, 9.05-21.09) and the negative likelihood ratio 0.38 (CI, 0.33-0.44). The odds ratio for having SLE in ANuA-positive patients is 40.7. The comparative analysis on anti-dsDNA antibodies conducted on the 26 studies which provided data for both antibodies showed that ANuA have greater diagnostic sensitivity (59.9% vs 52.4%) and a specificity rating only slightly higher (94.9% vs 94.2%). The probability that a subject with positive ANuA have SLE is 41 times greater than a subject with negative ANuA, while for anti-dsDNA the probability is 28 times greater. These figures are even more impressive in children, in whom ANuA have an odds ratio for the diagnosis of SLE of 146, compared to 51 for anti-dsDNA antibodies. In selected studies, ANuA (p<0.0001) but not anti-dsDNA antibodies (p=0.256) were significantly associated with disease activity measured by the international score systems. However, neither antibody appears to correlate with kidney involvement. Data from the metanalysis have shown that ANuA have equal specificity but higher sensitivity and prognostic value than anti-dsDNA antibodies in the diagnosis of SLE. Despite a certain heterogeneity among the various studies, the use of ANuA appears more efficacious than anti-dsDNA. Copyright © 2012 Elsevier B.V. All rights reserved.
SATELLITE PLASMA SHEATH ANOMALIES,
Contents: Experimental Studies of the Kraus Effect Plasma Sheath and Screening around a Rapidly Moving Body Plasma Compression EEffects Produced...Kraus Effect Interaction of West Ford Needles with Earth’s Magnetosphere The Generation of Electromagnetic Waves in the Wake of a Satellite
Kraus Receives 2012 Mineral and Rock Physics Graduate Research Award
NASA Astrophysics Data System (ADS)
2013-08-01
Richard Kraus received the 2012 Mineral and Rock Physics Graduate Research Award, given annually to one or more promising young scientists for outstanding contributions achieved during their Ph.D. research. Recipients of this award are engaged in experimental and/or theoretical studies of Earth and planetary materials with the purpose of unraveling the physics and chemistry that govern their origins and physical properties. Kraus's thesis is entitled "On the thermodynamics of planetary impact events." He was formally presented with the award at the 2012 AGU Fall Meeting, held 3-7 December in San Francisco, Calif.
Muñoz-Nortes, Tamara; Pérez-Pérez, José Manuel; Ponce, María Rosa; Candela, Héctor; Micol, José Luis
2017-03-01
The characterization of mutants with altered leaf shape and pigmentation has previously allowed the identification of nuclear genes that encode plastid-localized proteins that perform essential functions in leaf growth and development. A large-scale screen previously allowed us to isolate ethyl methanesulfonate-induced mutants with small rosettes and pale green leaves with prominent marginal teeth, which were assigned to a phenotypic class that we dubbed Angulata. The molecular characterization of the 12 genes assigned to this phenotypic class should help us to advance our understanding of the still poorly understood relationship between chloroplast biogenesis and leaf morphogenesis. In this article, we report the phenotypic and molecular characterization of the angulata7-1 (anu7-1) mutant of Arabidopsis thaliana, which we found to be a hypomorphic allele of the EMB2737 gene, which was previously known only for its embryonic-lethal mutations. ANU7 encodes a plant-specific protein that contains a domain similar to the central cysteine-rich domain of DnaJ proteins. The observed genetic interaction of anu7-1 with a loss-of-function allele of GENOMES UNCOUPLED1 suggests that the anu7-1 mutation triggers a retrograde signal that leads to changes in the expression of many genes that normally function in the chloroplasts. Many such genes are expressed at higher levels in anu7-1 rosettes, with a significant overrepresentation of those required for the expression of plastid genome genes. Like in other mutants with altered expression of plastid-encoded genes, we found that anu7-1 exhibits defects in the arrangement of thylakoidal membranes, which appear locally unappressed. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.
Smith, Julie; Javanparast, Sara; Craig, Lyn
2017-03-01
In 1999, two leading Australian academics challenged Australian universities to lead moves to better manage employees' maternity and breastfeeding needs, and 'bring babies and breasts into workplaces'. This paper addresses the question of how universities cope with the need for women to breastfeed, by exploring barriers facing women who combine breastfeeding and paid work at the Australian National University (ANU). Data were collected through online surveys in 2013 using mixed method, case study design, nested within a larger national study. Participants were 64 working mothers of children aged 0-2 years from the ANU community of employees and users of on-campus child care. Responses highlighted the ad hoc nature of support for breastfeeding at ANU. Lack of organisational support for breastfeeding resulted in adverse consequences for some ANU staff. These included high work-related stresses and premature cessation of breastfeeding among women who had intended to breastfeed their infants in line with health recommendations.
78 FR 44577 - Senior Executive Service Performance Review Board
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-24
..., William Tate, Cornelius F. Taylor, Charles Teets, Gregory L. Tennyson, Stephanie L. Thomas, Rob C.... Andrews, John Armstrong, Charles R. Armstrong, Sue Ayala, Janice Baer, Thomas Baran, Kathy Barber, Delores Baroukh, Nader Barrett, Lawrence Barrows, Angela Bartoldus, Charles Batkin, Joshua C. Bauhs, Kimberlyn J...
Oliveira, Rodrigo C.; Oliveira, Isabela S.; Santiago, Mittermayer B.; Sousa Atta, Maria L. B.; Atta, Ajax M.
2015-01-01
We investigated in Brazilian women with SLE the prevalence and levels of high avidity (HA) dsDNA antibodies and tested their correlation with lupus activity and biomarkers of renal disease. We also compared these correlations to those observed with total dsDNA antibodies and antibodies against nucleosome (ANuA). Autoantibodies were detected by ELISA, while C3 and C4 levels were determined by nephelometry. Urine protein/creatinine ratio was determined, and lupus activity was measured by SLEDAI-2K. The prevalence of total and HA dsDNA antibodies was similar to but lower than that verified for ANuA. The levels of the three types of antibodies were correlated, but the correlation was more significant between HA dsDNA antibodies and ANuA. High avidity dsDNA antibodies correlated positively with ESR and SLEDAI and inversely with C3 and C4. Similar correlations were observed for ANuA levels, whereas total dsDNA antibodies only correlated with SLEDAI and C3. The levels of HA dsDNA antibodies were higher in patients with proteinuria, but their levels of total dsDNA antibodies and ANuA were unaltered. High avidity dsDNA antibodies can be found in high prevalence in Brazilian women with SLE and are important biomarkers of active disease and kidney dysfunction. PMID:26583157
Oliveira, Rodrigo C; Oliveira, Isabela S; Santiago, Mittermayer B; Sousa Atta, Maria L B; Atta, Ajax M
2015-01-01
We investigated in Brazilian women with SLE the prevalence and levels of high avidity (HA) dsDNA antibodies and tested their correlation with lupus activity and biomarkers of renal disease. We also compared these correlations to those observed with total dsDNA antibodies and antibodies against nucleosome (ANuA). Autoantibodies were detected by ELISA, while C3 and C4 levels were determined by nephelometry. Urine protein/creatinine ratio was determined, and lupus activity was measured by SLEDAI-2K. The prevalence of total and HA dsDNA antibodies was similar to but lower than that verified for ANuA. The levels of the three types of antibodies were correlated, but the correlation was more significant between HA dsDNA antibodies and ANuA. High avidity dsDNA antibodies correlated positively with ESR and SLEDAI and inversely with C3 and C4. Similar correlations were observed for ANuA levels, whereas total dsDNA antibodies only correlated with SLEDAI and C3. The levels of HA dsDNA antibodies were higher in patients with proteinuria, but their levels of total dsDNA antibodies and ANuA were unaltered. High avidity dsDNA antibodies can be found in high prevalence in Brazilian women with SLE and are important biomarkers of active disease and kidney dysfunction.
Race Differences and Type II Errors: A Comment on Borkowski and Krause.
ERIC Educational Resources Information Center
Jensen, Arthur R.
1985-01-01
Borkowski and Krause (1983) concluded that the locus of black-white intelligence differences lies in metaprocesses not elementary cognitive processes. However, some variables were difference scores with unacceptably low reliability. Magnitude comparisons of racial differences give a different picture of results; comparable differences in measures…
Sensor Selection from Independence Graphs using Submodularity
2017-02-01
Krause , B. McMahan, Guestrin C., and Gupta A., “Robust sub- modular observation selection,” Journal of Machine Learning Research (JMLR), vol. 9, pp. 2761...235–257. Springer Berlin Heidelberg, 1983. [10] A. Krause , “SFO: A toolbox for submodular function optimization,” J. Mach. Learn. Res., vol. 11, pp
Fulfilling Dreams: Transitions into an ECE Online Preservice Teacher Education Degree
ERIC Educational Resources Information Center
Taylor, Pauline
2009-01-01
There is increased attention on the first year experience at universities generally as a result of the Australian federal government's focus on increased accountability for universities and widening participation in further education (DEST, 2003; Jardine & Krause, 2005; Kift, 2005; Krause, Hartley, James & McInnes, 2005). However, these…
1988-04-01
HABILITATION ) AS WELL AS FOR DIVERS. KRAUSE P C & ASSOCS INC 1414 RAVINIA RD WEST LAFAYETTE, IN 47906 CONTRACT NUMBER: PAUL C KRAUSE TITLE: MODELING OF SHIPBOARD...ELECTRONIC, HYDRODYNAMIC AND CON- TROL SYSTEM CHARACTERISTICS OF A SUITABLE SUBSEA ROBOT. IT WILL ALSO DESCRIBE THE SENSORY DEVICES, ACOUSTIC, VIDEO
Autoantibodies in SLE but not in scleroderma react with protein-stripped nucleosomes.
Suer, Waltraud; Dähnrich, Cornelia; Schlumberger, Wolfgang; Stöcker, Winfried
2004-06-01
Autoantibodies against nucleosomes (ANuA) are known to be sensitive markers for systemic lupus erythematosus (SLE), but their clinical relevance seemed to be limited because sera from patients with progressive systemic sclerosis (PSS) also showed positive reactions with conventional ANuA ELISA test systems (anti-Nu1 ELISA). It was generally assumed thatANuA were associated with both diseases. Using discontinuous sucrose gradient centrifugation to generate pure nucleosomes, we discovered by chance that at the 30-50% sucrose interface an antigen (Nu2) banded which was demonstrably free of non-histone components and histone H1. The two different nucleosome preparations, Nu1 and Nu2, were used in parallel as antigenic substrates in standardised ELISA tests to analyse sera from SLE (295 patients), PSS (119) and patients with other rheumatic diseases (101). With Nu1, 62% of the SLE and 52% of the PSS sera showed positive reactions. Two sera from patients suffering from Sjögren's syndrome (SS) and one from polymyositis were also positive. Using the Nu2 preparation, 58% of the SLE but none of the PSS sera showed a positive reaction. One serum from a patient with SS was also positive. It could be shown that it was the PSS-specific autoantigen Scl-70 in the nucleosome preparation (Nu1) which contributed to the positive reactions of the PSS sera in conventional ANuA test systems, whereas in the Nu2 preparation no remaining Scl-70 was detectable. The present study definitely proved that ANuA are highly and specifically associated with SLE but not with PSS.
A Personal Memoir of Policy Failure: The Failed Merger of ANU and the Canberra CAE
ERIC Educational Resources Information Center
Scott, Roger
2004-01-01
The more immediate context of the events the author describes in this article is needed in order to identify the policy framework within which the Australian National University (ANU)-Canberra CAE (CCAE) merger was placed as a component of a wider public policy initiative undertaken by John Dawkins. There were four major components in that wider…
2013-02-15
Matthew James, Andre Carvalho and Michael Hush completed some work analyzing cross-phase modulation using single photon quantum filtering techniques...ANU Michael Hush January – June, 2012, Postdoc, ANU Matthew R. James Professor, Australian National University Ian R. Petersen Professor...appear, IEEE Trans. Aut. Control., 2013. A. R. R. Carvalho, M. R. Hush , and M. R. James, “Cavity driven by a single photon: Conditional dynamics and
NASA Astrophysics Data System (ADS)
Schmidt, Peter; Lund, Björn; Näslund, Jens-Ove; Fastook, James
2014-05-01
Observations of glacial isostatic adjustment (GIA) have been used both to study the mechanical properties of the Earth and to invert for Northern Hemisphere palaeo-ice-sheets. This is typically done by solving the sea-level equation using simplified scaling laws to control ice-sheet thickness. However, past ice-sheets can also be reconstructed based on thermo-mechanical modelling driven by palaeo-climate data, invoking simple analytical models to account for the Earth's response. Commonly, both approaches use dated geological markers to constrain the ice-sheet margin location. Irrespective of the approach, the resulting ice-sheet reconstruction depends on the earth response, although the interdependence between the ice model and the earth model differs and therefore the two types of reconstructions could provide complementary information on Earth properties. We compare a thermo-mechanical reconstruction of the Weichselian ice-sheet using the UMISM model (Näslund, 2010) to two GIA driven reconstructions, ANU (Lambeck et al., 2010) and ICE-5G (Peltier & Fairbanks, 2006), commonly used in GIA modelling. We evaluate the three reconstructions both in terms of ice-sheet configurations and predicted Fennoscandian surface deformation ICE-5G comprise the largest reconstructed ice-sheet whereas ANU and UMISM are more similar in volume and areal extent. Significant differences still exists between ANU and UMISM, especially during the final deglaciation phase. Prior to the final retreat of the ice-sheet, ICE-5G is displays a massive and more or less constant ice-sheet configuration, while both ANU and UMISM fluctuates with at times almost ice-free conditions, such as during MIS3. This results in ICE-5G being close to isostatic equilibrium at LGM, whereas ANU and UMISM are not. Hence, the pre-LGM evolution of the Weichselian ice-sheet needs to be considered in GIA studies. For example, perturbing the ANU or UMISM reconstructions we find that changes more recent than 36 kyr BP may change the predicted uplift velocities by more than 0.1 mm/yr, while changes more recent than 55 kyr BP may change the predicted uplift 10 kyr ago by more than 5 m. Despite their differences we find that all three reconstructions can equally well fit observations of the present day uplift in Fennoscandia, as well as the observed sea-level curve along the Ångerman river, Sweden, albeit with different optimal earth models. However, only for ANU can a single optimal earth model be determined as a bifurcation in the optimal viscosity arises from the generally faster present day rebound rates in ICE-5G and UMISM, resulting in a range of well-fitting earth models for the latter reconstructions. Studying models with a reasonable fit to observed present day uplift velocities we find general trends of over- and under-prediction, indicating that all three ice-sheet reconstructions need improvement. In general, all three reconstructions tend to over-predict the uplift rates in southwestern Fennoscandia, whereas over Finland ICE-5G generally over-predicts and ANU generally under-predicts the uplift rates. UMISM tend to under-predict the velocities over central to northern Sweden and similar trends can also be seen in ANU and ICE-5G.
NASA Astrophysics Data System (ADS)
Schmidt, P.; Lund, B.; Näslund, J.-O.
2013-12-01
In this study we compare a recent reconstruction of the Weichselian ice-sheet as simulated by the University of Main ice-sheet model (UMISM) to two reconstructions commonly used in glacial isostatic adjustment (GIA) modeling: ICE-5G and ANU (also known as RSES). The UMISM reconstruction is carried out on a regional scale based on thermo-mechanical modelling whereas ANU and ICE-5G are global models based on the sea-level equation. The Weichselian ice-sheet in the three models are compared directly in terms of ice volume, extent and thickness, as well as in terms of predicted glacial isostatic adjustment in Fennoscandia. The three reconstructions display significant differences. UMISM and ANU includes phases of pronounced advance and retreat prior to the last glacial maximum (LGM), whereas the thickness and areal extent of the ICE-5G ice-sheet is more or less constant up until LGM. The final retreat of the ice-sheet initiates at earliest time in ICE-5G and latest in UMISM, while ice free conditions are reached earliest in UMISM and latest in ICE-5G. The post-LGM deglaciation style also differs notably between the ice models. While the UMISM simulation includes two temporary halts in the deglaciation, the later during the Younger Dryas, ANU only includes a decreased deglaciation rate during Younger Dryas and ICE-5G retreats at a relatively constant pace after an initial slow phase. Moreover, ANU and ICE-5G melt relatively uniformly over the entire ice-sheet in contrast to UMISM which melts preferentially from the edges. We find that all three reconstructions fit the present day uplift rates over Fennoscandia and the observed relative sea-level curve along the Ångerman river equally well, albeit with different optimal earth model parameters. Given identical earth models, ICE-5G predicts the fastest present day uplift rates and ANU the slowest, ANU also prefers the thinnest lithosphere. Moreover, only for ANU can a unique best fit model be determined. For UMISM and ICE-5G there is a range of earth models that can reproduce the present day uplift rates equally well. This is understood from the higher present day uplift rates predicted by ICE-5G and UMISM, which results in a bifurcation in the best fit mantle viscosity. Comparison of the uplift histories predicted by the ice-sheets indicate that inclusion of relative sea-level data in the data fit can reduce the observed ambiguity. We study the areal distributions of present day residual surface velocities in Fennoscandia and show that all three reconstructions generally over-predict velocities in southwestern Fennoscandia and that there are large differences in the fit to the observational data in Finland and northernmost Sweden and Norway. These difference may provide input to further enhancements of the ice-sheet reconstructions.
Final Report: PAGE: Policy Analytics Generation Engine
2016-08-12
develop a parallel framework for it. We also developed policies and methods by which a group of defensive resources (e.g. checkpoints) could be...Sarit Kraus. Learning to Reveal Information in Repeated Human -Computer Negotiation, Human -Agent Interaction Design and Models Workshop 2012. 04-JUN...Joseph Keshet, Sarit Kraus. Predicting Human Strategic Decisions Using Facial Expressions, International Joint Conference on Artificial
Development of Respiratory Sampling to Assess Stress Responses in North Atlantic Right Whales
2012-09-30
blow: It is possible. Marine Mammal Science 25(3):605-618. Hunt KE, Rolland RM, Kraus SD, Wasser SK. 2006. Analysis of fecal glucocorticoids in the...5 November 2009. Rolland RM, Hunt KE, Kraus SD, Wasser SK. 2005. Assessing reproductive status of right whales (Eubalaena glacialis) using fecal hormone metabolites. General and Comparative Endocrinology 142:308-317.
Cherbuin, Nicolas; Shaw, Marnie E; Walsh, Erin; Sachdev, Perminder; Anstey, Kaarin J
2017-12-14
Strong evidence is available suggesting that effective reduction of exposure to demonstrated modifiable risk factors in mid-life or before could significantly decrease the incidence of Alzheimer's disease (AD) and delay its onset. A key ingredient to achieving this goal is the reliable identification of individuals at risk well before they develop clinical symptoms. The aim of this study was to provide further neuroimaging evidence of the effectiveness of a validated tool, the ANU Alzheimer's Disease Risk Index, for the assessment of future risk of cognitive decline. Participants were 461 (60-64 years, 48% female) community-living individuals free of dementia at baseline. Associations between risk estimates obtained with the ANU-ADRI, total and regional brain volumes including in the default mode network (DMN) measured at the same assessment and diagnosis of MCI/dementia over a 12-year follow-up were tested in a large sample of community-living individuals free of dementia at baseline. Higher risk estimates on the ANU-ADRI were associated with lower cortical gray matter and particularly in the DMN. Importantly, difference in participants with high and low risk scores explained 7-9% of the observed difference in gray matter volume. In this sample, every one additional risk point on the ANU-ADRI was associated with an 8% increased risk of developing MCI/dementia over a 12-year follow-up and this association was partly mediated by a sub-region of the DMN. Risk of cognitive decline assessed with a validated instrument is associated with gray matter volume, particularly in the DMN, a region known to be implicated in the pathological process of the disease.
Air & Space Power Journal. Volume 18, Number 3, Fall 2004
2004-09-01
110 Martin W. Bowman Reviewer: Col (sel) Merrick E. Krause , USAF History of the... Krause Special Assistant to the Chairman, Joint Chiefs of Staff Dr. Charles Krupnick US Army War College Dr. Benjamin S. Lambeth RAND Lt Col David...in prepara tion for the summit. Thus, the WPC worked in conjunction with the AIRNORTH tactical evaluation (TacEval) office of Lt Col Wolfgang
Development of Respiratory Sampling to Assess Stress Responses in North Atlantic Right Whales
2011-09-30
hormones in whale blow: It is possible. Marine Mammal Science 25(3):605-618. Hunt K.E., Rolland R.M., Kraus S.D., and Wasser S.K. 2006. Analysis of...Hunt, K.E., Kraus, S.D. and Wasser , S.K. 2005. Assessing reproductive status of right whales (Eubalaena glacialis) using fecal hormone metabolites. General and Comparative Endocrinology 142:308-317.
VizieR Online Data Catalog: Late-type targets in Taurus, Cha I, and Upper Sco (Todorov+, 2014)
NASA Astrophysics Data System (ADS)
Todorov, K. O.; Luhman, K. L.; Konopacky, Q. M.; McLeod, K. K.; Apai, D.; Ghez, A. M.; Pascucci, I.; Robberto, M.
2017-07-01
To characterize the multiplicity of low-mass stars and brown dwarfs in Taurus and Chamaeleon I, we combine the results from our survey with those from previous high-resolution images in these regions. The latter were collected with WFPC2 (Kraus et al. 2006ApJ...649..306K), Keck speckle imaging (Konopacky et al. 2007ApJ...663..394K), and Keck AO imaging (Kraus & Hillenbrand 2012, J/ApJ/757/141) in Taurus and with WFPC2 (Neuhauser et al. 2002A&A...384..999N), the Advanced Camera for Surveys on Hubble (Luhman 2007, J/ApJS/173/104), and AO at the Very Large Telescope (Ahmic et al. 2007ApJ...671.2074A; Lafreniere et al. 2008ApJ...683..844L) in Chamaeleon I. For comparison to these two regions, we also have compiled binary data measured for late-type members of the Upper Sco association ({tau}~11 Myr; Pecaut et al. 2012, J/ApJ/746/154) with WFPC2 and Keck AO (Kraus et al. 2005ApJ...633..452K; Biller et al. 2011ApJ...730...39B; Kraus & Hillenbrand 2012, J/ApJ/757/141). (1 data file).
1942-05-01
2000 rpm and 160° E Inlet==Air Temperature ?erformanoe Of.zeferenoe fuels,- When teeted at 2000 rpm aad 150° ~ Inlet-air temperatu ~e, the referenoe...naphtha 70 peroent phosphorlo acid iso-ootane in 15 percent light naphtha and 15 percent benzene 56 percent aviation alkyl- ate and 9 percent hydro
1989-01-01
Calculations and Experiments (B.van den Berg/ D.A. Humphreysl E. Krause /J.P. F. Lindhout) Volume 20 Proceedings of the Seventh GAMM-Conference on...GRID METHODS FOR HYPERBOLIC PROBLEMS Wolfgang Hackbusch Sigrid Hagemann Institut fUr Informatik und Praktische Mathematik Christian-Albrechts...Euler Equations. Proceedings of the 8th Inter- national Conference on Numerical Methods in Fluid Dynamics (E. Krause , ed.), Aachen, 1988. Springer
NASA Astrophysics Data System (ADS)
Schmidt, P.; Lund, B.; Näslund, J.-O.; Fastook, J.
2014-05-01
In this study we compare a recent reconstruction of the Weichselian Ice Sheet as simulated by the University of Maine ice sheet model (UMISM) to two reconstructions commonly used in glacial isostatic adjustment (GIA) modelling: ICE-5G and ANU (Australian National University, also known as RSES). The UMISM reconstruction is carried out on a regional scale based on thermo-mechanical modelling, whereas ANU and ICE-5G are global models based on the sea level equation. The three models of the Weichselian Ice Sheet are compared directly in terms of ice volume, extent and thickness, as well as in terms of predicted glacial isostatic adjustment in Fennoscandia. The three reconstructions display significant differences. Whereas UMISM and ANU includes phases of pronounced advance and retreat prior to the last glacial maximum (LGM), the thickness and areal extent of the ICE-5G ice sheet is more or less constant up until the LGM. During the post-LGM deglaciation phase ANU and ICE-5G melt relatively uniformly over the entire ice sheet in contrast to UMISM, which melts preferentially from the edges, thus reflecting the fundamental difference in the reconstruction scheme. We find that all three reconstructions fit the present-day uplift rates over Fennoscandia equally well, albeit with different optimal earth model parameters. Given identical earth models, ICE-5G predicts the fastest present-day uplift rates, and ANU the slowest. Moreover, only for ANU can a unique best-fit model be determined. For UMISM and ICE-5G there is a range of earth models that can reproduce the present-day uplift rates equally well. This is understood from the higher present-day uplift rates predicted by ICE-5G and UMISM, which result in bifurcations in the best-fit upper- and lower-mantle viscosities. We study the areal distributions of present-day residual surface velocities in Fennoscandia and show that all three reconstructions generally over-predict velocities in southwestern Fennoscandia and that there are large differences in the fit to the observational data in Finland and northernmost Sweden and Norway. These difference may provide input to further enhancements of the ice sheet reconstructions.
Determinants and Politics of German Military Transformation in the Post-Cold War Era
2011-06-01
Jahrhundert, eds. Joachim Krause and Jan C. Irlenkaeuser (Opladen: Verlag Barbara Budrich, 2006), 97. 2 military changed after the end of the Cold...Anforderungen an deutsche Streitkräfte im 21. Jahrhundert, eds. Joachim Krause and Jan C. Irlenkaeuser (Opladen: Verlag Barbara Budrich, 2006), 182. 12...2007), 763–778; Svenja Sinjen and Johannes Varwick, 101-106; Wolfgang Wagner, ―Die Außen-, Sicherheits- und Verteidigungspolitik der Europäischen
2014-09-01
for the different motives of proliferators.145 Joachim Krause wrote in 2007 that some members of the Clinton administration believed that they...preventing WMD use, which effectively linked deterrence to counterproliferation. 146 Joachim Krause , “Enlightenment and Nuclear Order,” International...173 Despite the concerns of some commentators, such as Daryl Kimball and Wolfgang Panofsky, Keith Payne argued that assurance was a necessary defense
Coalition Logistics: A Case Study in Operation Restore Hope
1994-06-03
coalition operations."° In Seland’s interview with Colonel Wolfgang Kopp, chief of staff, German/Franco Brigade, Colonel Kopp stated that key members...February 1994. 21William G. Pagonis and Michael D. Krause , "Operational Logistics and the Gulf War," The Institute of Land Warfare: The Land Warfare...Headquarters, 1989. Pagonis, William G. and Michael D. Krause . "Operational Logistics and the Gulf War." The Land Warfare Paper No. 13. Arlington, Virginia
The Tumor Suppressor Actions of the Vitamin D Receptor in Skin
2013-08-01
S. Yu, et al., Basal cell carcinomas inmiceoverexpressing Gli2 in skin, Nature Genetics 24 (3) (2000) 216–217. 61] M. Nilsson, A.B. Unden, D. Krause ...Meineke V, Gartner BC, Wolfgang T, Holick MF, Reichrath J. Analysis of the vitamin D system in cutaneous malignancies. Recent Results Cancer Res...10700170] 63. Nilsson M, Unden AB, Krause D, Malmqwist U, Raza K, Zaphiropoulos PG, Toftgard R. Induction of basal cell carcinomas and trichoepitheliomas
2011-09-30
by Rosalind M. Rolland, Susan E. Parks, Kathleen E. Hunt, Manuel Castellote, Peter J. Corkeron, Douglas P. Nowacek, Samuel K. Wasser and Scott D...Partitioning. Journal of Computational and Graphical Statistics. 15(3): 651-674. Hunt KE, Rolland RM, Kraus SD, Wasser SK. 2006. Analysis of fecal...KE, Kraus SD, Wasser SK. 2005. Assessing reproductive status of right whales (Eubalaena glacialis) using fecal hormone metabolites. General and
Robledo, M; Rivera, L; Jiménez-Zurdo, Jose I; Rivas, R; Dazzo, F; Velázquez, E; Martínez-Molina, E; Hirsch, Ann M; Mateos, Pedro F
2012-09-12
The synthesis of cellulose is among the most important but poorly understood biochemical processes, especially in bacteria, due to its complexity and high degree of regulation. In this study, we analyzed both the production of cellulose by all known members of the Rhizobiaceae and the diversity of Rhizobium celABC operon predicted to be involved in cellulose biosynthesis. We also investigated the involvement in cellulose production and biofilm formation of celC gene encoding an endoglucanase (CelC2) that is required for canonical symbiotic root hair infection by Rhizobium leguminosarum bv. trifolii. ANU843 celC mutants lacking (ANU843ΔC2) or overproducing cellulase (ANU843C2+) produced greatly increased or reduced amounts of external cellulose micro fibrils, respectively. Calcofluor-stained cellulose micro fibrils were considerably longer when formed by ANU843ΔC2 bacteria rather than by the wild-type strain, in correlation with a significant increase in their flocculation in batch culture. In contrast, neither calcofluor-stained extracellular micro fibrils nor flocculation was detectable in ANU843C2+ cells. To clarify the role of cellulose synthesis in Rhizobium cell aggregation and attachment, we analyzed the ability of these mutants to produce biofilms on different surfaces. Alteration of wild-type CelC2 levels resulted in a reduced ability of bacteria to form biofilms both in abiotic surfaces and in planta. Our results support a key role of the CelC2 cellulase in cellulose biosynthesis by modulating the length of the cellulose fibrils that mediate firm adhesion among Rhizobium bacteria leading to biofilm formation. Rhizobium cellulose is an essential component of the biofilm polysaccharidic matrix architecture and either an excess or a defect of this "building material" seem to collapse the biofilm structure. These results position cellulose hydrolytic enzymes as excellent anti-biofilm candidates.
2012-01-01
Background The synthesis of cellulose is among the most important but poorly understood biochemical processes, especially in bacteria, due to its complexity and high degree of regulation. In this study, we analyzed both the production of cellulose by all known members of the Rhizobiaceae and the diversity of Rhizobium celABC operon predicted to be involved in cellulose biosynthesis. We also investigated the involvement in cellulose production and biofilm formation of celC gene encoding an endoglucanase (CelC2) that is required for canonical symbiotic root hair infection by Rhizobium leguminosarum bv. trifolii. Results ANU843 celC mutants lacking (ANU843ΔC2) or overproducing cellulase (ANU843C2+) produced greatly increased or reduced amounts of external cellulose micro fibrils, respectively. Calcofluor-stained cellulose micro fibrils were considerably longer when formed by ANU843ΔC2 bacteria rather than by the wild-type strain, in correlation with a significant increase in their flocculation in batch culture. In contrast, neither calcofluor-stained extracellular micro fibrils nor flocculation was detectable in ANU843C2+ cells. To clarify the role of cellulose synthesis in Rhizobium cell aggregation and attachment, we analyzed the ability of these mutants to produce biofilms on different surfaces. Alteration of wild-type CelC2 levels resulted in a reduced ability of bacteria to form biofilms both in abiotic surfaces and in planta. Conclusions Our results support a key role of the CelC2 cellulase in cellulose biosynthesis by modulating the length of the cellulose fibrils that mediate firm adhesion among Rhizobium bacteria leading to biofilm formation. Rhizobium cellulose is an essential component of the biofilm polysaccharidic matrix architecture and either an excess or a defect of this “building material” seem to collapse the biofilm structure. These results position cellulose hydrolytic enzymes as excellent anti-biofilm candidates. PMID:22970813
Rubidium Recycling in a High Intensity Short Duration Pulsed Alkali Laser
2010-03-01
16. C. Ottinger, R. Scheps, G. W. York, and A. Gallagher, Physical Review A 11:1815, 1975. 17. Nathan D. Zameroski, Wolfgang Rudolph, Gordon D...Lijnse, P. J. Th. Zeegers, and C. Th. J. Alkemade, J. Quant. Spectrosc. Radiat. Transf. 13:1033, 1973. 21. E. S. Hrysyshyn and L. Krause . Can. J...Phys 48:2761, 1970. 22. J. A. Bellisio, P. Davidovits, and P. J. Kindlmann. J. Chem. Phys. 48:2376, 1968. 23. R. A. Phaneuf and L. Krause . Can J
On Contemporary War and the German Armed Forcs: The Afghan War and and Its Consequenes
2014-06-01
Minister of Defense Volker Rühe, and in 2008 amended during the term of office of Minister of Defense Dr. Jung, it 38 Wolfgang Schneiderhahn, “Das Bild... Krause (Opladen: Verlag Barbara Budrich, 2006), 233. 134 Reiner Pommerin, “Vom ‘Kalten Krieg’ zu globaler Konfliktverhütung und Krisenbewältigung...Jahrhundert [Bundeswehr: The Next 50 Years, Demands on German Forces in the 21st Century], edited by Jan C. Irlenkaeuser, Joachim Krause . Opladen
1982-01-15
Systems U. HEILEVANN, Cyclical Taxonomy and Large Econometic Models D. HINRICHSEN, U. KRAUSE , Triangulation of Convex Polyhedra with an Application to...Classification of Economic Fluctua- tions, "Explorations in Economic Research", vol.2 (1975), pp. 167-2o2. -196- D. Hinrich3en and U. Krause Department...d’opti- misation de structures, Those de doctuer ingenieur, Universit6 de Paris VI, 1976. -211- - *. ____________________ -__-____- Wolfgang Nooss
Friends Indeed? Coalition Burden Sharing and the War In Iraq. Volume 1
2008-08-05
Malici, "Germans as Venutians: The Culture of German Foreign Policy Behavior." 36 Joachim Krause , "The Role of the Bundestag in German Foreign Policy...Hampshire ; New York: Palgrave, 2001), 159. 37 Erb, German Foreign Policy: Navigating a New Era, 191. 38 Krause , "The Role of the Bundestag in German...policy expert Wolfgang Schaeuble accused the German government of “creating a bogey” and weakening the United Nations in the Iraq debate for its
Characterizing avulsion stratigraphy in ancient alluvial deposits
NASA Astrophysics Data System (ADS)
Jones, H. L.; Hajek, E. A.
2007-11-01
Guidelines for identifying ancient avulsion deposits were set forth by Kraus and Wells [Kraus, M.J., Wells, T.M., 1999. Recognizing avulsion deposits in the ancient stratigraphical record. In: Smith, N.D., Rogers, J. (Eds.), Fluvial Sedimentology VI, Special Publication of the International Association of Sedimentologists, vol. 28, pp. 251-268], building on the study by Smith et al. [Smith, N.D., Cross, T.A., Dufficy, J.P., Clough, S.R., 1989. Anatomy of an avulsion. Sedimentology 36, 1-23] of the modern Saskatchewan River system (Cumberland Marshes, central Canada), and serve to characterize avulsion depositional sequences in the ancient Willwood and Fort Union Formations (Paleogene, Bighorn Basin, NW Wyoming, USA). We recognize, however, that the model is not universally applicable to avulsion-dominated successions, specifically systems which lack defining "heterolithic avulsion deposits", set forth by Kraus and Wells [Kraus, M.J., Wells, T.M., 1999. Recognizing avulsion deposits in the ancient stratigraphical record. In: Smith, N.D., Rogers, J. (Eds.), Fluvial Sedimentology VI, Special Publication of the International Association of Sedimentologists, vol. 28, pp. 251-268]. Observations in several fluvial intervals suggest that the avulsion stratigraphy outlined by Kraus and Wells [Kraus, M.J., Wells, T.M., 1999. Recognizing avulsion deposits in the ancient stratigraphical record. In: Smith, N.D., Rogers, J. (Eds.), Fluvial Sedimentology VI, Special Publication of the International Association of Sedimentologists, vol. 28, pp. 251-268] represents one category of avulsion stratigraphy found in the rock record, but does not capture the nature of avulsion deposits everywhere. Based on observations (using measured sections, outcrop photo-panels, and aerial photographs) in the Willwood Formation (Eocene, Wyoming) and Ferris Formation (Cretaceous/Paleogene, Wyoming), we present two end-member categories of avulsion stratigraphy in ancient deposits; stratigraphically abrupt, when a main paleochannel is stratigraphically juxtaposed directly atop floodplain/overbank deposits, and stratigraphically transitional, where crevasse splays and other non-floodplain/-overbank deposits stratigraphically precede a main paleochannel. This characterization provides a broader, more inclusive way to recognize and describe avulsion stratigraphy in ancient deposits and may be an important factor to consider when modeling connectivity in fluvial reservoirs. Furthermore, our observations show that one type of avulsion channel stratigraphy may prevail over another within an ancient basin, suggesting that system-wide factors such as splay-proneness or avulsion style (i.e. aggradational, incisional, etc.; [Slingerland, R., Smith, N.D., 2004. River avulsions and their deposits. Annual Review of Earth and Planetary Sciences 32, 257-285]) may be primary controls on the type of avulsion stratigraphy deposited and preserved in ancient basin-fills.
NASA Astrophysics Data System (ADS)
Kohler, Susanna
2017-10-01
Growing a planet from a dust grain is hard work! A new study explores how vortices in protoplanetary disks can assist this process.When Dust Growth FailsTop: ALMA image of the protoplanetary disk of V1247 Orionis, with different emission components labeled. Bottom: Synthetic image constructed from the best-fit model. [Kraus et al. 2017]Gradual accretion onto a seed particle seems like a reasonable way to grow a planet from a grain of dust; after all, planetary embryos orbit within dusty protoplanetary disks, which provides them with plenty of fuel to accrete so they can grow. Theres a challenge to this picture, though: the radial drift problem.The radial drift problem acknowledges that, as growing dust grains orbit within the disk, the drag force on them continues to grow as well. For large enough dust grains perhaps around 1 millimeter the drag force will cause the grains orbits to decay, and the particles drift into the star before they are able to grow into planetesimals and planets.A Close-Up Look with ALMASo how do we overcome the radial drift problem in order to form planets? A commonly proposed mechanism is dust trapping, in which long-lived vortices in the disk trap the dust particles, preventing them from falling inwards. This allows the particles to persist for millions of years long enough to grow beyond the radial drift barrier.Observationally, these dust-trapping vortices should have signatures: we would expect to see, at millimeter wavelengths, specific bright, asymmetric structures where the trapping occurs in protoplanetary disks. Such disk structures have been difficult to spot with past instrumentation, but the Atacama Large Millimeter/submillimeter Array (ALMA) has made some new observations of the disk V1247 Orionis that might be just what were looking for.Schematic of the authors model for the disk of V1247 Orionis. [Kraus et al. 2017]Trapped in a Vortex?ALMAs observations of V1247 Orionis are reported by a team of scientists led by Stefan Kraus (University of Exeter) in a recent publication. Kraus and collaborators show that the protoplanetary disk of V1247 Orionis contains a ring-shaped, asymmetric inner disk component, as well as a sharply confined crescent structure. These structures are consistent with the morphologies expected from theoretical models of vortex formation in disks.Kraus and collaborators propose the following picture: an early planet is orbiting at 100 AU within the disk, generating a one-armed spiral arm as material feeds the protoplanet. As the protoplanet orbits, it clears a gap between the ring and the crescent, and it simultaneously triggers two vortices, visible as the crescent and the bright asymmetry in the ring. These vortices are then able to trap millimeter-sized particles.Gas column density of the authors radiation-hydrodynamic simulation of V1247 Orioniss disk. [Kraus et al. 2017]The authors run detailed hydrodynamics simulations of this scenario and compare them (as well as alternative theories) to the ALMA observations of V1247 Orionis. The simulations support their model, producing sample scattered-light images thatmatchwell the one-armed spiral observed in previous scattered-light images of the disk.How can we confirm V1247 Orionis providesan example of dust-trapping vortices? One piece of supporting evidence would be the discovery of the protoplanet that Kraus and collaborators theorize triggered the potential vortices in this disk. Future deeper ALMA imaging may make this possible, helping to confirm our picture of how dust builds into planets.CitationStefan Kraus et al 2017 ApJL 848 L11. doi:10.3847/2041-8213/aa8edc
2012-09-30
potentially providing information on nutritional state and chronic stress ( Wasser et al., 2010). We tested both T3 and T4 assays for parallelism.The...EconPapers.RePEc.org/RePEc:inn:wpaper:2011-20 Hunt K.E., Rolland R.M., Kraus S.D., Wasser S.K. 2006. Analysis of fecal glucocorticoids in the North Atlantic right...version 1.2.5. http://CRAN.R-project.org/package=doMC Rolland R.M., Hunt K.E., Kraus S.D., Wasser S.K. 2005. Assessing reproductive status of right
Lee, Yin Huey; Barnard, Amanda; Owen, Cathy
2011-01-01
Rural health workforce issues are a priority area for the Australian Government and substantial funding has been provided for rural education programs to address health workforce disparities across Australia's rural and remote communities. The Australian Government established a Rural Health Strategy in 2001 and as a result there are now 14 rural clinical schools in Australia. The 2008 Urbis Report highlighted the lack of research on rural programs and workforce outcomes, essential to ensuring that educational efforts, resources and funding are being concentrated appropriately. This study examined the Australian National University (ANU) Medical School's 4 year rural program to identify the impact of elective and compulsory program components on student intentions to practice in a rural and remote location post-graduation. The study also explores factors that affect student decisions to apply for year-long rural placements. METHODS; ANU Medical School's graduating cohort of 2008 fourth year medical students completed an anonymous and voluntary online survey questionnaire. Survey sections included student demographics, compulsory and elective components of the ANU rural program, and an overall evaluation of the ANU rural curriculum. The survey contained a mixture of forced-answer questions and open-ended commentary. Quantitative data were analyzed for descriptive and frequency statistics using EpiInfo V3.5.1 (http://wwwn.cdc.gov/epiinfo/). Qualitative data were reviewed and consistent themes among responses extracted. In total, 40 students from a cohort of 88 (45%) responded, with 26 respondents (65%) indicating that at medical school commencement they considered working in a rural or remote area. At the end of their medical education, 33 respondents (82%) indicated their intention to spend some time in their careers working in a rural or remote area. Students from non-rural backgrounds had greater positive change in their intentions to practice rurally as a direct effect of ANU rural programs when compared with students from rural backgrounds. More than 70% of students believed the amount of rural focus in the curriculum was correct, 75% believed that they will be better medical practitioners because of the program, and 85% found the curriculum was delivered effectively. Students who undertook elective rural programs such as a year-long rural placement were more likely to have future rural career intentions when compared with students undertaking compulsory rural components. Compulsory components, however, had a strong influence on students applying for elective programs. Regarding application for the year-long rural placement, students reported clinical exposure was the most encouraging factor, and time away from family and friends, and lack of spousal and family support were the most discouraging factors. Rural programs at the ANU, and medical school exposure to rural health experiences is important in influencing students' perceptions of a career in rural and remote health. This study provides evidence that both compulsory and elective components contribute to a successful holistic rural program which nurtures the rural interest of all students. Overall, students at the ANU medical school were satisfied with the rural curriculum. The results confirm that there is difficulty in recruiting students with family commitments into year-long rural placement programs, despite incentives. Those students who select long-term rural study for reasons other than an interest in a career in rural health end the program with positive rural intentions.
Wind-Tunnel Investigation of Rear Underslung Fuselage Ducts
1943-09-01
reqfiring them for the wu effort. They were pre- viously held under a security status but are now unclassified. Some of these reports were not tech ...boundary layer away from the main cooling duet. Good pressuro reoovsries were obtained Zn the duets with tho use of either the inlet gutd-vane...below trailing edge of outlet guide vane APPARATUS AED 5!ES2S A description of the MACA full-scale tunnel and the equipment used for the teete is
1994-03-01
Oft-«) D-mt) Munich 50 Prof. Dring. Wolfgang Braig Universität Stuttgart Institut für Luftfahrtantriebe Pfaffenwaldring 6 D-7000 Stuttgart 80...Symposium, May, 1977. 3.20 MQff»t,R.J., Designing Thermocouples for Response Rate, ASME Paper No. 57-CTP-8. 3.21 Glawe, G.E., Holanda, R., and Krause ...Science and Industry, Vol.3, Part 2, 1962. 4.3.3 Glawe, G.E., Holanda, R., Krause , L.N., Recovery and Radiation Corrections and Time Constants of
1980-09-01
GRHI78 de Grande and Hirsch (1978) JOHN70 Johnston (1970) LAL071 Larsson (1974) 0254 LOHM73 Lohmann (1973) MUKR79 M6ller and Krause (1979) PIDU74 Pierce...motion," Dissertation, University of Connecticut. MUller, U., and E. Krause (1979). "Measurements of mean velocities and Reynolds stresses in an...Chairman Dr. P. J. Roache 4925 Kathryn Circle S.E. Eval. Comm.; Albuquerque, NM 87108 Compt’..or A.63 Dr. Wolfgang Rodi Sonderforschungsbereich 80 Data Eval
Laplace approximation for Bessel functions of matrix argument
NASA Astrophysics Data System (ADS)
Butler, Ronald W.; Wood, Andrew T. A.
2003-06-01
We derive Laplace approximations to three functions of matrix argument which arise in statistics and elsewhere: matrix Bessel A[nu]; matrix Bessel B[nu]; and the type II confluent hypergeometric function of matrix argument, [Psi]. We examine the theoretical and numerical properties of the approximations. On the theoretical side, it is shown that the Laplace approximations to A[nu], B[nu] and [Psi] given here, together with the Laplace approximations to the matrix argument functions 1F1 and 2F1 presented in Butler and Wood (Laplace approximations to hyper-geometric functions with matrix argument, Ann. Statist. (2002)), satisfy all the important confluence relations and symmetry relations enjoyed by the original functions.
Optical and Infrared Photometry of SN 2005df
NASA Astrophysics Data System (ADS)
Krisciunas, Kevin; Suntzeff, Nicholas B.; Espinoza, Juan; Gonzalez, David; Miranda, Alberto; Sanhueza, Pedro
2017-12-01
We present optical BVRI and near-infrared YJHK_s photometry of the normal Type Ia supernova 2005df, obtained with the CTIO 1.3-m and 0.9-m telescopes. The B- and V-band photometry, S-corrected to the filter prescriptions of Bessell(1990), matches the corresponding photometry from the ANU published by Milne et al. (2010). The R-band photometry from CTIO and ANU matches well without any corrections. A combination of V-band and near-IR photometry shows that SN 2005df is unreddened in its host galaxy. Spectropolarimetry of this supernova was obtained with the VLT, and the distance to the host galaxy is being determined from observations of Cepheids using the Hubble Space Telescope.
de Chambrier, Alain; Coquille, Sandrine C; Mariaux, Jean; Tkach, Vasyl
2009-05-01
Testudotaenia testudo (Magath, 1924) is redescribed from the intestine of the softshell turtle Apalone spinifera (Le Sueur) (Trionychidae) and the bowfin Amia calva Linnaeus (Amiidae) from Reelfoot Lake, Tennessee, United States. A new subfamily, the Testudotaeniinae, is erected. The new taxon differs from all proteocephalidean subfamilies in the position of the genital organs in relation to the longitudinal internal musculature, i.e. the testes are cortical, rarely medullary; the ovary is partly medullary, with cortical lobes; the vitelline follicles are mainly medullary, with some follicles in the cortex; and the uterus is cortical. A key to the subfamilies of the order Proteocephalidea Mola, 1928 is provided. The most characteristic features of T. testudo are the precocious uterine aperture, the presence of internal uterine pores (as previously described for Proteocephalus paraguayensis (Rudin, 1917)), the eggs laid unripe, the very long strobila (up to 970 mm), and the presence of an anterior circular musculature in the suckers, which is considered as a good differential character. Three other species were found in Amia calva: Proteocephalus perplexus La Rue, 1911, P. ambloplitis (Leidy, 1887) and a new, undescribed form. Sequences of the partial nuclear 28S rRNA gene of specimens of T. testudo from Apalone spinulifera and Amia calva confirm the conspecificity of samples from these two very distinct hosts, which may represent a capture phenomenon. As the subfamily Adenobrechmoinae Bursey, Goldberg & Kraus, 2006 and the genus Adenobrechmos Bursey, Goldberg & Kraus, 2006 are based on the presence of an apical organ, a character which reflects a rather common convergence, we consider the Adenobrechmoinae to be a junior synonym of the Proteocephalinae La Rue, 1911 and Adenobrechmos a junior synonym of Ophiotaenia La Rue, 1911. Adenobrechmos greeri Bursey, Goldberg & Kraus, 2006 thus becomes Ophiotaenia greeri (Bursey, Goldberg & Kraus, 2006) n. comb.
Borges, Marcus Kiiti; Jacinto, Alessandro Ferrari; Citero, Vanessa de Albuquerque
2017-01-01
Alzheimer's disease (AD) represents a major public health problem and it is therefore crucial that modifiable risk factors be known prior to onset of dementia in late-life. The "Australian National University - Alzheimer's Disease Risk Index" (ANU-ADRI) is one of the potential tools for primary prevention of the disease. Objective The aim of this study was to devise an adapted version of the ANU-ADRI for use in Brazil. Methods The instrument was translated from its original language of English into Portuguese and then back-translated into English by bilingual translators. It was subsequently reviewed and evaluated as to the degree of translation issues and equivalence. In this study, the ANU-ADRI was applied using individual (face-to-face) interviews in a public hospital, unlike the original version which is applied online by self-report. The final version (pretest) was evaluated in a sample of 10 participants with a mean age of 60 years (±11.46) and mean education of 11 years (±6.32). Results The intraclass correlation coefficient (ICC) (inter-rater) was 0.954 (P<0.001 for a confidence interval (CI) of 95%=[0.932; 0.969]). Cultural equivalence was performed without the need for a second instrument application step. Conclusion After cross-cultural adaptation, the language of the resultant questionnaire was deemed easily understandable by the Brazilian population. PMID:29213508
Borges, Marcus Kiiti; Jacinto, Alessandro Ferrari; Citero, Vanessa de Albuquerque
2017-01-01
Alzheimer's disease (AD) represents a major public health problem and it is therefore crucial that modifiable risk factors be known prior to onset of dementia in late-life. The "Australian National University - Alzheimer's Disease Risk Index" (ANU-ADRI) is one of the potential tools for primary prevention of the disease. The aim of this study was to devise an adapted version of the ANU-ADRI for use in Brazil. The instrument was translated from its original language of English into Portuguese and then back-translated into English by bilingual translators. It was subsequently reviewed and evaluated as to the degree of translation issues and equivalence. In this study, the ANU-ADRI was applied using individual (face-to-face) interviews in a public hospital, unlike the original version which is applied online by self-report. The final version (pretest) was evaluated in a sample of 10 participants with a mean age of 60 years (±11.46) and mean education of 11 years (±6.32). The intraclass correlation coefficient (ICC) (inter-rater) was 0.954 (P<0.001 for a confidence interval (CI) of 95%=[0.932; 0.969]). Cultural equivalence was performed without the need for a second instrument application step. After cross-cultural adaptation, the language of the resultant questionnaire was deemed easily understandable by the Brazilian population.
Nasofacial defect following fibrosarcoma excision and radiotherapy.
Burget, G L; Panje, W R; Krause, C J
1988-01-01
For initial reconstruction, Dr. Burget suggests that he would have advanced the cheek flap medially toward the nasal septum and, subsequently, reconstructed the missing right half of the nose with a forehead flap and cartilage grafts. Dr. Panje suggested early prosthetic rehabilitation, while Dr. Krause's concepts were similar to Dr. Burget's, with forehead flap nasal reconstruction, after cheek reconstruction to the nasofacial and nasolabial lines with a medially advanced cheek flap. Dr. Panje recommended an immediate maxillary denture prosthesis, as did Dr. Krause (who supplemented this with foam rubber). Dr. Burget placed the prosthesis 3 weeks after tumor ablation. For skin grafts, Drs. Panje and Burget suggested split thickness grafts to all new surfaces to decrease wound contracture, while Dr. Krause used dermis grafts for the same purpose. Other reconstructive methods mentioned were the (1) cervical tubed flap, (2) free scapular flap, (3) Washio flap, (4) tissue expansion, and (5) nasolabial flap. Suggestions for isolated defects included: Lower eyelid--increase internal support by building up the prosthesis; release lower lid from deltopectoral flap and V-Y advancement; support graft or irradiated cartilage (1-2 mm sheet) under orbicularis oculi. Nasal ala--bring present ala down and insert cartilage graft; turn internal skin down and fill the resulting defect with a composite graft. Upper lip--multiple Z-plasty. Retrodisplacement of cheek due to maxillectomy--release buccal scar; skin graft the raw internal surface and build up prosthesis.
Sorokin, Vladislav V; Belyaeva, Inna A; Shamonin, Mikhail; Kramarenko, Elena Yu
2017-06-01
The dynamic shear modulus of magnetoactive elastomers containing 70 and 80 mass % of carbonyl iron microparticles is measured as a function of strain amplitude via dynamic torsion oscillations in various magnetic fields. The results are presented in terms of the mechanical energy density and considered in the framework of the conventional Kraus model. The form exponent of the Kraus model is further related to a physical model of Huber et al. [Huber et al., J. Phys.: Condens. Matter 8, 409 (1996)10.1088/0953-8984/8/29/003] that uses a realistic representation for the cluster network possessing fractal structure. Two mechanical loading regimes are identified. At small strain amplitudes the exponent β of the Kraus model changes in an externally applied magnetic field due to rearrangement of ferromagnetic-filler particles, while at large strain amplitudes, the exponent β seems to be independent of the magnetic field. The critical mechanical energy characterizing the transition between these two regimes grows with the increasing magnetic field. Similarities between agglomeration and deagglomeration of magnetic filler under simultaneously applied magnetic field and mechanical shear and the concept of jamming transition are discussed. It is proposed that the magnetic field should be considered as an additional parameter to the jamming phase diagram of rubbers filled with magnetic particles.
1993-03-25
manually . M2F=3.28083989 A=size( HTP ); TO= HTP (I,2)+273.15; PO= HTP (I,3); H0= HTP (1,1); R=287.04; GSL=9.7957; H=[]; P3=0; RAD=20820807; axis((0,5000,0,30...contributed, but I would especially like to acknowledge Bob Nagy of the Geophysics Department for his assistance in providing, and interpreting the...teet to under 250 feet at an altitude of 30,000 feet. The method does require the sounding data to be manually examined to pick out the layer. When a
Genetics Home Reference: myoclonus-dystonia
... Page Esapa CT, Waite A, Locke M, Benson MA, Kraus M, McIlhinney RA, Sillitoe RV, Beesley PW, ... PubMed Gerrits MC, Foncke EM, Koelman JH, Tijssen MA. Pediatric writer's cramp in myoclonus-dystonia: maternal imprinting ...
Connected components of irreducible maps and 1D quantum phases
DOE Office of Scientific and Technical Information (OSTI.GOV)
Szehr, Oleg, E-mail: oleg.szehr@posteo.de; Wolf, Michael M., E-mail: wolf@ma.tum.de
We investigate elementary topological properties of sets of completely positive (CP) maps that arise in quantum Perron-Frobenius theory. We prove that the set of primitive CP maps of fixed Kraus rank is path-connected and we provide a complete classification of the connected components of irreducible CP maps at given Kraus rank and fixed peripheral spectrum in terms of a multiplicity index. These findings are then applied to analyse 1D quantum phases by studying equivalence classes of translational invariant matrix product states that correspond to the connected components of the respective CP maps. Our results extend the previously obtained picture inmore » that they do not require blocking of physical sites, they lead to analytic paths, and they allow us to decompose into ergodic components and to study the breaking of translational symmetry.« less
1985-10-31
7 oat s LinkI . . - P Comments: ~ y V ,~o.*.-’ ,. 157q Pk: 6ETtC*6L- - ’ . */-’-..- -,.-., Oats Teet Poit c C 2 b AmplifI481OS’ dS Attenuaio 2-4D dB...Puleer Level * Data LinkI Comments: /:2- VO%’ a*1 Date/3 - Attenuaion dS HMmontai na/dIv I Vertial mnV/div I s. Horizontal g n a/div 2 Vertical IV
ERIC Educational Resources Information Center
Lozada, Marlene; And Others
1996-01-01
Profiles the American Vocational Association vocational teacher of the year, Rebecca Rhodes, in "Coming Full Circle" (Lozada); the outstanding vocational educator, Roy Peters, Jr., in "The Shoes Fit" (Dykman); and the outstanding new vocational teacher, Ann Krause, in "First Love" (Vo). (SK)
76 FR 23571 - Marine Mammals and Endangered Species; File Nos. 15415 and 14622
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-27
... border. Dr. Kraus is authorized to conduct control and experimental visual trials to determine if right... during non-linear transect surveys and hand capture loggerhead, Kemp's ridley, and hawksbill sea turtles...
[Jena philosophies of nature around 1800].
Breidbach, O
2000-01-01
This paper describes the situation and the outline of positions in philosophy of nature in Jena about 1800, in focusing on research other than the key figures Schelling and Hegel. In 1789, Schelling introduced philosophy of nature into the course program of Jena University. Already in 1800, two young scientists--a mathematician (Fischer) and a physiologist--reacted, announcing lectures on Schellingian topics. But only in late 1802, younger philosophers offered courses on those topics. From 1802 onwards, lectures were announced by Schad, Krause, Henrici, Hegel, Oken and the botanist Schelver. Apart from the Fisher lecture from 1800, the program of these presentations was based on Schellingian principles. Analyses of the ideas of Schad, Krause and Schelver show that, about 1800, philosophy of nature in Jena conserved basic ideas of the early philosophy of nature of Schelling. Thus, philosophy of nature in this period of Jena University seemed to follow just one line of reasoning.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Akibue, Seiseki; Murao, Mio
2014-12-04
We investigate distributed implementation of two-qubit unitary operations over two primitive networks, the butterfly network and the ladder network, as a first step to apply network coding for quantum computation. By classifying two-qubit unitary operations in terms of the Kraus-Cirac number, the number of non-zero parameters describing the global part of two-qubit unitary operations, we analyze which class of two-qubit unitary operations is implementable over these networks with free classical communication. For the butterfly network, we show that two classes of two-qubit unitary operations, which contain all Clifford, controlled-unitary and matchgate operations, are implementable over the network. For the laddermore » network, we show that two-qubit unitary operations are implementable over the network if and only if their Kraus-Cirac number do not exceed the number of the bridges of the ladder.« less
Collective motion in animal groups
NASA Astrophysics Data System (ADS)
Couzin, Iain
2004-03-01
In recent years there has been a growing interest in the relationship between individual behavior and population-level properties in animal groups. One of the fundamental problems is related to spatial scale; how do interactions over a local range result in population properties at larger, averaged, scales, and how can we integrate the properties of aggregates over these scales? Many group-living animals exhibit complex, and coordinated, spatio-temporal patterns which despite their ubiquity and ecological importance are very poorly understood. This is largely due to the difficulties associated with quantifying the motion of, and interactions among, many animals simultaneously. It is on how these behaviors scale to collective behaviors that I will focus here. Using a combined empirical approach (using novel computer vision techniques) and individual-based computer models, I investigate pattern formation in both invertebrate and vertebrate systems, including - Collective memory and self-organized group structure in vertebrate groups (Couzin, I.D., Krause, J., James, R., Ruxton, G.D. & Franks, N.R. (2002) Journal of Theoretical Biology 218, 1-11. (2) Couzin, I.D. & Krause, J. (2003) Advances in the Study of Behavior 32, 1-75. (3) Hoare, D.J., Couzin, I.D. Godin, J.-G. & Krause, J. (2003) Animal Behaviour, in press.) - Self-organized lane formation and optimized traffic flow in army ants (Couzin, I.D. & Franks, N.R. (2003) Proceedings of the Royal Society of London, Series B 270, 139-146) - Leadership and information transfer in flocks, schools and swarms. - Why do hoppers hop? Hopping and the generation of long-range order in some of the largest animal groups in nature, locust hopper bands.
A Theoretical Model Analysis of Absorption of a Three level Diode Pumped Alkali Laser
2009-03-01
2.10) 103 Bibliography Demtroder, Wolfgang . Laser Spectroscopy: Basic Concepts and Instrumentation. Berlin: Springer...Konefal Z., “Observation of collision induced processes in rubidium-ethane vapour,” Optics Communication, 164:95-105 (1999). Krause , L
77 FR 2083 - Notice of Inventory Completion: Minnesota Indian Affairs Council, Bemidji, MN
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-13
... the north side of Height of Land Lake, site 21BK48, by Mr. William Krause during road construction and... near Ice Cracking Lake during road construction and donated to the Becker County Historical Society (HR...
Identification of significant E0 strength in the 22+ → 21+ transitions of 58,60,62Ni
NASA Astrophysics Data System (ADS)
Evitts, L. J.; Garnsworthy, A. B.; Kibédi, T.; Smallcombe, J.; Reed, M. W.; Brown, B. A.; Stuchbery, A. E.; Lane, G. J.; Eriksen, T. K.; Akber, A.; Alshahrani, B.; de Vries, M.; Gerathy, M. S. M.; Holt, J. D.; Lee, B. Q.; McCormick, B. P.; Mitchell, A. J.; Moukaddam, M.; Mukhopadhyay, S.; Palalani, N.; Palazzo, T.; Peters, E. E.; Ramirez, A. P. D.; Stroberg, S. R.; Tornyi, T.; Yates, S. W.
2018-04-01
The E0 transition strength in the 22+ →21 + transitions of 58,60,62Ni have been determined for the first time following a series of measurements at the Australian National University (ANU) and the University of Kentucky (UK). The CAESAR Compton-suppressed HPGe array and the Super-e solenoid at ANU were used to measure the δ (E 2 / M 1) mixing ratio and internal conversion coefficient of each transition following inelastic proton scattering. Level half-lives, δ (E 2 / M 1) mixing ratios and γ-ray branching ratios were measured at UK following inelastic neutron scattering. The new spectroscopic information was used to determine the E0 strengths. These are the first 2+ →2+E0 transition strengths measured in nuclei with spherical ground states and the E0 component is found to be unexpectedly large; in fact, these are amongst the largest E0 transition strengths in medium and heavy nuclei reported to date.
VizieR Online Data Catalog: Activity and rotation in Praesepe and the Hyades (Douglas+, 2014)
NASA Astrophysics Data System (ADS)
Douglas, S. T.; Agueros, M. A.; Covey, K. R.; Bowsher, E. C.; Bochanski, J. J.; Cargile, P. A.; Kraus, A.; Law, N. M.; Lemonias, J. J.; Arce, H. G.; Fierroz, D. F.; Kundert, A.
2017-05-01
Kraus & Hillenbrand (2007, J/AJ/134/2340) calculated proper motions and photometry for several million objects within 7° of the center of Praesepe. The resulting catalog includes 1128 candidate cluster members with membership probabilities Pmem>50%. As in Paper I (Agueros et al. 2011ApJ...740..110A), we supplement this catalog with 41 known members that are too bright to be identified as members by Kraus & Hillenbrand (2007, J/AJ/134/2340). For the Hyades, we adopt the Roser et al. (2011, J/A+A/531/A92) membership catalog. These authors identified candidate Hyades members via the convergent point method and confirmed membership using photometry. We used the MDM Observatory Modular Spectrograph (ModSpec) on the Hiltner 2.4 m telescope to obtain spectra of stars in Praesepe and the Hyades over the course of five multi-night runs between 2010 December 2 and 2012 November 14. (2 data files).
KEGS Transients Discovered by a Pan-STARRS1 Search of the Kepler Campaign 16 Field
NASA Astrophysics Data System (ADS)
Smith, K. W.; Rest, A.; Tucker, B. E.; Garnavich, P. M.; Margheim, S.; Kasen, D.; Olling, R.; Shaya, E.; Narayan, G.; Villar, A.; Forster, F.; Mushotzky, R.; Zenteno, A.; James, D.; Smith, R. Chris; Dotson, J. L.; Barentsen, G.; Gully-Santiago, M.; Smartt, S. J.; Wright, D. E.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Schultz, A.; Magnier, E.; Waters, C.; Bulger, J.; Wainscoat, R. J.
2018-01-01
We report the following transients discovered by Pan-STARRS1 during a targeted search of the Kepler Campaign 16 field as part of the K2 Extragalactic Survey (KEGS) for Transients (see http://www.mso.anu.edu.au/kegs/).
Air Force Academy Aeronautics Digest.
1985-04-01
7964, 1964. 10. Dudzinski, J.T. and L.N. Krause , Flow Direction Measurement with Fixed-Position Probes, NASA TMX-1904, 1969. 11. Beecham, L.J. and...Bob Hatfield in instrumenting the hot-wire airfoil model and refurbishing the pitching mechanism, Mr Russ Me inzer and Mr. Wolfgang Bank of the
2007-01-01
Cognition, 19, 229–240. Salladay, S. A. (1982). In the event of death. Omega - Journal of Death & Dying, 13, 1–11. Salo, S., Krause , K...Psychoenergetic Systems, 1, 87–89. Wolfgang , A. (1973). A cross-cultural comparison of locus of control, optimism toward the future and time horizon
1993-02-01
Engineer Waterways Experiment Station, Vicksburg, MS, POC: Dr. Nicholas Kraus, (601) 634- 2018 . ______________’I.9 DRP Technical Area 1 workshop scheduled...I uold ask you is, ’What are which has been the " bible "of coastal en- videotape to reaffirm my commitment to the avenues we should pursue in this
KEGS Discovery of 28 Supernova Candidates in the K2 Campaign 17 Field with DECam
NASA Astrophysics Data System (ADS)
Narayan, G.; Rest, A.; Strampelli, G. M.; Zenteno, A.; James, D. J.; Smith, R. C.; Tucker, B. E.; Garnavich, P.; Margheim, S.; Kasen, D.; Olling, R.; Shaya, E.; Buron, F. Forster; Villar, V. A.
2018-05-01
The Kepler Extra-Galactic Survey (KEGS, see http://www.mso.anu.edu.au/kegs/ ) reports the discovery of 28 supernova candidates with the Dark Energy Camera (DECam, NOAO 2017B-0285) on the 4m Blanco Telescope at Cerro Tololo Inter-American Observatory (CTIO).
Hall devices improve electric motor efficiency
NASA Technical Reports Server (NTRS)
Haeussermann, W.
1979-01-01
Efficiency of electric motors and generators is reduced by radial magnetic forces created by symmetric fields within device. Forces are sensed and counteracted by Hall devices on excitation or control windings. Hall generators directly measure and provide compensating control of anu asymmetry, eliminating additional measurements needed for calibration feedback control loop.
Meeting the Needs and Interests of Today's High School Student
ERIC Educational Resources Information Center
Krause, Tracy
2014-01-01
This article describes how the physical educators at Tahoma High School, in a community in Washington state's Cascade Mountains, surveyed their students, reached out to the community, integrated physical education and academics, and established a school-wide focus on wellness. Tracy Krause writes that the three "Rs"--relationships,…
An Update on Teaching the Employment Search.
ERIC Educational Resources Information Center
Andrews, Deborah, Ed.; Dyrud, Marilyn A., Ed.
1997-01-01
Presents five articles dealing with teaching job search strategies: (1) "Preparing a Scannable Resume" (Carol Roever); (2) "Preparing an Online Resume" (Tim Krause); (3) "Using the World Wide Web to Teach Employment Communication" (K. Virginia Hemby); (4) "A Visual Heuristic for Promoting a Rhetorically Based Job Search" (Helen Foster); and (5)…
Student Engagement and Making Community Happen
ERIC Educational Resources Information Center
McGowan, Wayne S.; Partridge, Lee
2014-01-01
Student engagement and making community happen is a policy manoeuvre that shapes the political subjectivity of the undergraduate student In Australia, making community happen as a practice of student engagement is described as one of the major challenges for policy and practice in research-led universities (Krause, 2005). Current efforts to meet…
Multi-Target Tracking for Swarm vs. Swarm UAV Systems
2012-09-01
Uhlmann, “Using covariance intersection for SLAM,” Robotics and Autonomous Systems, vol. 55, pp. 3–20, Jan. 2007. [10] R. B. G. Wolfgang Niehsen... Krause , J. Leskovec, and C. Guestrin, “Data association for topic intensity track- ing,” Proceedings of the 23rd international conference on Machine
Air and Space Power Joumal. Volume 25, Number 3, Fall 2011
2011-01-01
Navarre, Florida Mr. Charles Tustin Kamps USAF Air Command and Staff College Dr. Tom Keaney Johns Hopkins University Col Merrick E. Krause , USAF, Retired...fighter pilots such as Wolfgang Falck, Hajo Herrmann, and Hans-Joachim Jabs. In this aspect, Heaton (a professor at the American Military University
Administrative Training: What Really Prepares Administrators for the Job?
ERIC Educational Resources Information Center
Kraus, Christine M.
This paper describes part of a study (Kraus 1996) involving 25 school administrators who attended one of five administrator preparation programs at four New England universities. The study addressed research questions regarding perceptions of administrators' job preparedness and how components of formal training programs (i.e., internships,…
Development of a Mechanically Mediated RF to Optical Transducer
2017-05-22
in radio astronomy receivers could be replaced by this noise- tolerant transducer, thus dramatically reducing the system’s size and cost [7]. Such a...conversion between microwave and optical light. Nat. Phys. 10, 321-326 (2014). [7] Kraus, J.D., Radio Astronomy (McGraw, 1966). [8] DARPA Optical Radiation
Genetics Home Reference: vitelliform macular dystrophy
... Bird TD, Ledbetter N, Mefford HC, Smith RJH, Stephens K, editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2017. Available from http://www.ncbi.nlm.nih.gov/books/NBK1167/ Citation on PubMed Renner AB, Tillack H, Kraus H, Kohl S, Wissinger B, Mohr N, Weber ...
Flight Test Experiments Foreseen for USV
2005-10-01
USA W.T. - Japan W .T. - Australia: ANU ( National University) W .T. - USA: NASA , AEDC, CALTEC, CUBRC W .T. - Japan: NAL 1.0E-05 1.0E-04... reflectometry ”. • Active (TX / RX) / passive (RX only) mode experiments • Main on-board elements: • RX • TX (possibly shared with system TX) • antennas
Leading Change: Applying Change Management Approaches to Engage Students in Blended Learning
ERIC Educational Resources Information Center
Quinn, Diana; Amer, Yousef; Lonie, Anne; Blackmore, Kim; Thompson, Lauren; Pettigrove, Malcolm
2012-01-01
The Australian National University (ANU) and the University of South Australia (UniSA) have embarked on Federally-funded project to collaborate in the design, development and delivery of a range of undergraduate and postgraduate courses in engineering. The collaboration investigates new ways to bring together the strengths and discipline expertise…
Peakall, Rod; Smouse, Peter E
2012-10-01
GenAlEx: Genetic Analysis in Excel is a cross-platform package for population genetic analyses that runs within Microsoft Excel. GenAlEx offers analysis of diploid codominant, haploid and binary genetic loci and DNA sequences. Both frequency-based (F-statistics, heterozygosity, HWE, population assignment, relatedness) and distance-based (AMOVA, PCoA, Mantel tests, multivariate spatial autocorrelation) analyses are provided. New features include calculation of new estimators of population structure: G'(ST), G''(ST), Jost's D(est) and F'(ST) through AMOVA, Shannon Information analysis, linkage disequilibrium analysis for biallelic data and novel heterogeneity tests for spatial autocorrelation analysis. Export to more than 30 other data formats is provided. Teaching tutorials and expanded step-by-step output options are included. The comprehensive guide has been fully revised. GenAlEx is written in VBA and provided as a Microsoft Excel Add-in (compatible with Excel 2003, 2007, 2010 on PC; Excel 2004, 2011 on Macintosh). GenAlEx, and supporting documentation and tutorials are freely available at: http://biology.anu.edu.au/GenAlEx. rod.peakall@anu.edu.au.
Basic data for some recent Australian heat-flow measurements
Munroe, Robert J.; Sass, J.H.; Milburn, G.T.; Jaeger, J.C.; Tammemagi, H.Y.
1975-01-01
This report has been compiled to provide background information and detailed temperature and thermal conductivity data for the heat-flow values reported in Sass, Jaeger, and Munroe (in press). The data were collected as part of a joint heat-flow study by the Australian National University (ANU) and the U.S. Geological Survey (USGS) under the direction of J. C. Jaeger (ANU) and J. H. Sass (USGS). The format is similar to that used for basic data from United States heat-flow determinations (Sass and Munroe, 1974). Each section contains a state map showing the geographic distribution of heat-flow data followed by tables which list individual temperatures, thermal conductivities, and radiogenic heat production values. A companion volume (Bunker and others, 1975) gives details of the heat-production measurements together with individual radioelement concentrations. Localities are arranged in alphabetical order within each state. The methods and techniques of measurements have been described by Sass and others (1971a, b). Unusual methods or procedures which differ markedly from these techniques are noted and described in the comments sections of the tables.
Cued Speech Transliteration: Effects of Accuracy and Lag Time on Message Intelligibility
ERIC Educational Resources Information Center
Krause, Jean C.; Lopez, Katherine A.
2017-01-01
This paper is the second in a series concerned with the level of access afforded to students who use educational interpreters. The first paper (Krause & Tessler, 2016) focused on factors affecting accuracy of messages produced by Cued Speech (CS) transliterators (expression). In this study, factors affecting intelligibility (reception by deaf…
Workplace Discrimination Outcomes and Their Predictive Factors for Adults with Multiple Sclerosis
ERIC Educational Resources Information Center
Roessler, Richard T.; Neath, Jeanne; McMahon, Brian T.; Rumrill, Phillip D.
2007-01-01
Because employment is a significant predictor of the quality of life of people with disabilities (Rumrill, Roessler, & Fitzgerald, 2004; Viermo & Krause, 1998), discrimination in the workplace that interferes with successful job acquisition or retention is a serious matter. Unfortunately, this type of discrimination is all too prevalent.…
Air and Space Power Journal. Volume 25, Number 3, Fall 2011
2011-01-01
Charles Tustin Kamps USAF Air Command and Staff College Dr. Tom Keaney Johns Hopkins University Col Merrick E. Krause , USAF, Retired Department of Homeland...conducted face-to-face interviews with many of the air war leaders and noble night-fighter pilots such as Wolfgang Falck, Hajo Herrmann, and Hans
University Curricula in the Marine Sciences and Related Fields. Academic Years 1969-70 and 1970-71.
1971-01-01
Associate Professor Krause , Dale C., Associate Professor 112 McMaster, Robert L., Ph.D., Associate Professor Smayda, Theodore J., Dr., Philos...Associate Professor of Zoology Division of Physical Sciences Allison, Edwin C., Ph.D., Professor of Geology Berger, Wolfgang , Ph.D., Assistant Professor of
2010-09-01
Austin Long, Daniel Altman, Gautam Mukunda, Ben Friedman, Peter Krause , Kelly Grieco, Brendan Green, Negeen Paghadi, and Jill Hazelton. A special thanks...Times, Saxon, Wolfgang (28 December 1985) "Airport Attacks Widely Deplored" New York Times 770 Reagan did not freeze Libyan financial assets and
Ocean Circulation and Dynamics on the West Antarctic Peninsula Continental Shelf
2007-09-01
Physical Oceanography, and Wolfgang Schneider, Renato Quifiones, Silvio Pantoja, Samuel Hormaz6bal and Oscar Pizarro all helped me learn more about how to be...Rohardt, G., Krause , G., 1992. The Antarctic coastal current in the southeastern Weddell Sea. Polar Biology 12 (2), 171-182. 178 Flagg, C. N
An Analysis of Female Representation and Marines Performance in Aviation and Logistics Occupations
2016-02-01
Parcell, Ann D., Apriel K. Hodari, and Robert W. Shuford. 2003. Predictors of Officer Success. CNA Corporation. CRM D0007437.A2/Final. [18] Kraus...Shuford. 2007. Black and Hispanic Marines: Their Accessions, Representation, Success, and Retention in the Corps. CNA Corporation. CRM D0016910.A1/Final
Math Anxiety, Working Memory, and Math Achievement in Early Elementary School
ERIC Educational Resources Information Center
Ramirez, Gerardo; Gunderson, Elizabeth A.; Levine, Susan C.; Beilock, Sian L.
2013-01-01
Although math anxiety is associated with poor mathematical knowledge and low course grades (Ashcraft & Krause, 2007), research establishing a connection between math anxiety and math achievement has generally been conducted with young adults, ignoring the emergence of math anxiety in young children. In the current study, we explored whether…
ERIC Educational Resources Information Center
Galilee-Belfer, Mika
2012-01-01
While research on barriers to full participation for those with learning and other disabilities has focused largely on structural and institutional obstacles to work and education (Swain, French, & Cameron, 2005; Jones, 1996; Watson, 2002), the recognition of disability as a social justice issue is gaining currency (Kraus, 2008). Expensive,…
ERIC Educational Resources Information Center
Gray, Howard R., Comp.; And Others
The following lectures are presented in this publication: (1) "The Dynamics of Recreation" (Betty Van der Smissen); (2) "Recreation Prospects" (Edith L. Ball); (3) "A View of the Past--A Bridge to the Future" (Allen V. Sapora); (4) "Coming to Grips with the New Leisure" (Richard G. Kraus); (5) "The Mild Blue Yonder--Changing Lifestyles and…
Band-aid for information loss from black holes
NASA Astrophysics Data System (ADS)
Israel, Werner; Yun, Zinkoo
2010-12-01
We summarize, simplify and extend recent work showing that small deviations from exact thermality in Hawking radiation, first uncovered by Kraus and Wilczek, have the capacity to carry off the maximum information content of a black hole. This goes a considerable way toward resolving a long-standing “information loss paradox.”
Sociophysics simulations II: opinion dynamics
NASA Astrophysics Data System (ADS)
Stauffer, Dietrich
2005-07-01
Individuals have opinions but can change them under the influence of others. The recent models of Sznajd (missionaries), of Deffuant et al. (negotiators), and of Krause and Hegselmann (opportunists) are reviewed here, while the voter and Ising models, Galam's majority rule and the Axelrod multicultural model were dealt with by other lecturers at this 8th Granada Seminar.
Model and simulation of Krause model in dynamic open network
NASA Astrophysics Data System (ADS)
Zhu, Meixia; Xie, Guangqiang
2017-08-01
The construction of the concept of evolution is an effective way to reveal the formation of group consensus. This study is based on the modeling paradigm of the HK model (Hegsekmann-Krause). This paper analyzes the evolution of multi - agent opinion in dynamic open networks with member mobility. The results of the simulation show that when the number of agents is constant, the interval distribution of the initial distribution will affect the number of the final view, The greater the distribution of opinions, the more the number of views formed eventually; The trust threshold has a decisive effect on the number of views, and there is a negative correlation between the trust threshold and the number of opinions clusters. The higher the connectivity of the initial activity group, the more easily the subjective opinion in the evolution of opinion to achieve rapid convergence. The more open the network is more conducive to the unity of view, increase and reduce the number of agents will not affect the consistency of the group effect, but not conducive to stability.
Adaptive recurrence quantum entanglement distillation for two-Kraus-operator channels
NASA Astrophysics Data System (ADS)
Ruan, Liangzhong; Dai, Wenhan; Win, Moe Z.
2018-05-01
Quantum entanglement serves as a valuable resource for many important quantum operations. A pair of entangled qubits can be shared between two agents by first preparing a maximally entangled qubit pair at one agent, and then sending one of the qubits to the other agent through a quantum channel. In this process, the deterioration of entanglement is inevitable since the noise inherent in the channel contaminates the qubit. To address this challenge, various quantum entanglement distillation (QED) algorithms have been developed. Among them, recurrence algorithms have advantages in terms of implementability and robustness. However, the efficiency of recurrence QED algorithms has not been investigated thoroughly in the literature. This paper puts forth two recurrence QED algorithms that adapt to the quantum channel to tackle the efficiency issue. The proposed algorithms have guaranteed convergence for quantum channels with two Kraus operators, which include phase-damping and amplitude-damping channels. Analytical results show that the convergence speed of these algorithms is improved from linear to quadratic and one of the algorithms achieves the optimal speed. Numerical results confirm that the proposed algorithms significantly improve the efficiency of QED.
Ellersieck, Mark R., Amha Asfaw, Foster L. Mayer, Gary F. Krause, Kai Sun and Gunhee Lee. 2003. Acute-to-Chronic Estimation (ACE v2.0) with Time-Concentration-Effect Models: User Manual and Software. EPA/600/R-03/107. U.S. Environmental Protection Agency, National Health and Envi...
1992-08-20
NAVAL STTRFACE WARFARE CENTER MR. KRATOVIL EDWARD NAVAL SEA SYSTEMS COMMAND MR KRAUSE WILLIAM UNITED TECHNOLOGIES-ASD MR. KRAUTHAMMER THEODOR PENN...ARMY DEPOT MR. WOLFGANG GARY OLIN ORDNANCE MR. WOOD RANDALL EG&G MOUND APPLIED TECHNOLOGIES MR. WOOD SCOTT NAVAL WEAPONS STATION - SEAL BEACH MR
Big Five Lessons for Today and Tomorrow
2012-05-29
55 i x Figure 39. MIM-14 Nike Hercules...Jane’s Pub Inc ., 2012). 24 http://www.army.mil/factfiles/equipment/tracked/abrams.html. Figure 9. Description of the Abrams Main Battle Tank 24...Vehicles, (Iola, WI: Krause Publications, 2003), 322. 31 Jane’s Armour and Artillery 1979-80, (New York: Jane’s Pub Inc ., 1980). XM765 Figure 14
Peakall, Rod; Smouse, Peter E.
2012-01-01
Summary: GenAlEx: Genetic Analysis in Excel is a cross-platform package for population genetic analyses that runs within Microsoft Excel. GenAlEx offers analysis of diploid codominant, haploid and binary genetic loci and DNA sequences. Both frequency-based (F-statistics, heterozygosity, HWE, population assignment, relatedness) and distance-based (AMOVA, PCoA, Mantel tests, multivariate spatial autocorrelation) analyses are provided. New features include calculation of new estimators of population structure: G′ST, G′′ST, Jost’s Dest and F′ST through AMOVA, Shannon Information analysis, linkage disequilibrium analysis for biallelic data and novel heterogeneity tests for spatial autocorrelation analysis. Export to more than 30 other data formats is provided. Teaching tutorials and expanded step-by-step output options are included. The comprehensive guide has been fully revised. Availability and implementation: GenAlEx is written in VBA and provided as a Microsoft Excel Add-in (compatible with Excel 2003, 2007, 2010 on PC; Excel 2004, 2011 on Macintosh). GenAlEx, and supporting documentation and tutorials are freely available at: http://biology.anu.edu.au/GenAlEx. Contact: rod.peakall@anu.edu.au PMID:22820204
Orgambide, G G; Huang, Z H; Gage, D A; Dazzo, F B
1993-11-01
The phospholipid and associated fatty acid compositions of the bacterial symbiont of clover, Rhizobium leguminosarum biovar trifolii wild-type ANU843, was analyzed by two-dimensional silica thin-layer chromatography, fast atom bombardment-mass spectrometry, flame-ionization detection gas-liquid chromatography and combined gas-liquid chromatography/mass spectrometry. The phospholipid composition included phosphatidylethanolamine (15%), N-methylphosphatidylethanolamine (47%), N,N-dimethylphosphatidylethanolamine (9%), phosphatidylglycerol (19%), cardiolipin (5%) and phosphatidylcholine (2%). Fatty acid composition included predominantly cis-11-octadecenoic acid, lower levels of cis-9-hexadecenoic acid, hexadecanoic acid, 11-methyl-11-octadecenoic acid, octadecanoic acid, 11,12-methyleneoctadecanoic acid, eicosanoic acid and traces of branched, and di- and triunsaturated fatty acids. The influence of expression of the "nodulation" genes encoding symbiotic functions on the composition of these membrane lipids was examined in wild-type cells grown with or without the flavone inducer, 4',7-dihydroxyflavone and in mutated cells lacking the entire symbiotic plasmid where these genes reside, or containing single transposon insertions in selected nodulation genes. No significant changes in phospholipid or associated fatty acid compositions were detected by the above methods of analysis.
Learning Theory Expertise in the Design of Learning Spaces: Who Needs a Seat at the Table?
ERIC Educational Resources Information Center
Rook, Michael M.; Choi, Koun; McDonald, Scott P.
2015-01-01
This study highlights the impact of including stakeholders with expertise in learning theory in a learning space design process. We present the decision-making process during the design of the Krause Innovation Studio on the campus of the Pennsylvania State University to draw a distinction between the architect and faculty member's decision-making…
Imagination and the Humanities in Honors across the Disciplines at a Jesuit University
ERIC Educational Resources Information Center
Kraus, Joe
2015-01-01
Not every student has done honors work in the humanities, but all students experience research at a human level that necessarily recalls the work of the humanities. This article describes how Joe Kraus, a professor of literature at the University of Scranton, was inspired to see applied humanities in stories of human experiences, which helped him…
1958-2008: 50 Years of Youth Fitness Tests in the United States
ERIC Educational Resources Information Center
Morrow, James R., Jr.; Zhu, Weimo; Franks, B. Don; Meredith, Marilu D.; Spain, Christine
2009-01-01
The AAHPER Youth Fitness Test, the first U.S. national fitness test, was published 50 years ago. The seminal work of Krause and Hirschland influenced the fitness world and continues to do so today. Important youth fitness test initiatives in the last half century are summarized. Key elements leading to continued interest in youth fitness testing…
NASA Astrophysics Data System (ADS)
Salprima Yudha, S.; Angasa, Eka; Suharto, Totok Eka; Nishina, Yuta; Mardlia, Zulfikri Achid; Sipriyadi
2016-02-01
Many reports recently show that some plant and animal extracts were useful to prepare some desired materials. In line with the statement, this report will present a bioresources candidate that can be used for green preparation of gold nanoparticles. The Scaevola fruteschen (Mill.) Krause was obtained from Enggano island, Bengkulu Province, Indonesia. The current research include synthesis, characterization and application study of the obtained nanoparticles in their original medium/reduction system as antibacterial agent of Escherichia coli. Besides that, the interaction study of the nanoparticles solution with Pb2+ ions was also studied. The results, shows that the present reduction system (aqueous extract of the plant leaves) successfully reduced gold (III) ions to gold metals as shown by new peak at 544 nm in spectrophotometry analysis. The average nanopartiles size was 96 nm based on Particles Size Analyzer (PSA) result. The stability study revealed that the nanoparticles solution was not stable in the persence of Pb(OAc)2 at high concentration. The nanoparticles were effective enough toward E. coli as shown by inhibition zone that indicates the degree of sensitivity of bacteria to nanoparticles.
NASA Astrophysics Data System (ADS)
2008-01-01
Using ESO's Very Large Telescope Interferometer, astronomers have probed the inner parts of the disc of material surrounding a young stellar object, witnessing how it gains its mass before becoming an adult. ESO PR Photo 03/08 ESO PR Photo 03a/08 The disc around MWC 147 (Artist's Impression) The astronomers had a close look at the object known as MWC 147, lying about 2,600 light years away towards the constellation of Monoceros ('the Unicorn'). MWC 147 belongs to the family of Herbig Ae/Be objects. These have a few times the mass of our Sun and are still forming, increasing in mass by swallowing material present in a surrounding disc. MWC 147 is less than half a million years old. If one associated the middle-aged, 4.6 billion year old Sun with a person in his early forties, MWC 147 would be a 1-day-old baby [1]. The morphology of the inner environment of these young stars is however a matter of debate and knowledge of it is important to better understand how stars and their cortège of planets form. The astronomers Stefan Kraus, Thomas Preibisch, and Keiichi Ohnaka have used the four 8.2-m Unit Telescopes of ESO's Very Large Telescope to this purpose, combining the light from two or three telescopes with the MIDI and AMBER instruments. "With our VLTI/MIDI and VLTI/AMBER observations of MWC147, we combine, for the first time, near- and mid-infrared interferometric observations of a Herbig Ae/Be star, providing a measurement of the disc size over a wide wavelength range [2]," said Stefan Kraus, lead-author of the paper reporting the results. "Different wavelength regimes trace different temperatures, allowing us to probe the disc's geometry on the smaller scale, but also to constrain how the temperature changes with the distance from the star." The near-infrared observations probe hot material with temperatures of up to a few thousand degrees in the innermost disc regions, while the mid-infrared observations trace cooler dust further out in the disc. The observations show that the temperature changes with radius are much steeper than predicted by the currently favoured models, indicating that most of the near-infrared emission emerges from hot material located very close to the star, that is, within one or two times the Earth-Sun distance (1-2 AU). This also implies that dust cannot exist so close to the star, since the strong energy radiated by the star heats and ultimately destroys the dust grains. ESO PR Photo 03/08 ESO PR Photo 03b/08 The Region Around MWC 147 "We have performed detailed numerical simulations to understand these observations and reached the conclusion that we observe not only the outer dust disc, but also measure strong emission from a hot inner gaseous disc. This suggests that the disc is not a passive one, simply reprocessing the light from the star," explained Kraus. "Instead, the disc is active, and we see the material, which is just transported from the outer disc parts towards the forming star." ESO PR Photo 03/08 ESO PR Photo 03c/08 Close-up on MWC 147 The best-fit model is that of a disc extending out to 100 AU, with the star increasing in mass at a rate of seven millionths of a solar mass per year. "Our study demonstrates the power of ESO's VLTI to probe the inner structure of discs around young stars and to reveal how stars reach their final mass," said Stefan Kraus. More Information The authors report their results in a paper in the Astrophysical Journal ("Detection of an inner gaseous component in a Herbig Be star accretion disk: Near- and mid-infrared spectro-interferometry and radiative transfer modeling of MWC 147", by Stefan Kraus, Thomas Preibisch, Keichii Ohnaka").
NASA Astrophysics Data System (ADS)
2008-01-01
Using ESO's Very Large Telescope Interferometer, astronomers have probed the inner parts of the disc of material surrounding a young stellar object, witnessing how it gains its mass before becoming an adult. ESO PR Photo 03/08 ESO PR Photo 03a/08 The disc around MWC 147 (Artist's Impression) The astronomers had a close look at the object known as MWC 147, lying about 2,600 light years away towards the constellation of Monoceros ('the Unicorn'). MWC 147 belongs to the family of Herbig Ae/Be objects. These have a few times the mass of our Sun and are still forming, increasing in mass by swallowing material present in a surrounding disc. MWC 147 is less than half a million years old. If one associated the middle-aged, 4.6 billion year old Sun with a person in his early forties, MWC 147 would be a 1-day-old baby [1]. The morphology of the inner environment of these young stars is however a matter of debate and knowledge of it is important to better understand how stars and their cortège of planets form. The astronomers Stefan Kraus, Thomas Preibisch, and Keiichi Ohnaka have used the four 8.2-m Unit Telescopes of ESO's Very Large Telescope to this purpose, combining the light from two or three telescopes with the MIDI and AMBER instruments. "With our VLTI/MIDI and VLTI/AMBER observations of MWC147, we combine, for the first time, near- and mid-infrared interferometric observations of a Herbig Ae/Be star, providing a measurement of the disc size over a wide wavelength range [2]," said Stefan Kraus, lead-author of the paper reporting the results. "Different wavelength regimes trace different temperatures, allowing us to probe the disc's geometry on the smaller scale, but also to constrain how the temperature changes with the distance from the star." The near-infrared observations probe hot material with temperatures of up to a few thousand degrees in the innermost disc regions, while the mid-infrared observations trace cooler dust further out in the disc. The observations show that the temperature changes with radius are much steeper than predicted by the currently favoured models, indicating that most of the near-infrared emission emerges from hot material located very close to the star, that is, within one or two times the Earth-Sun distance (1-2 AU). This also implies that dust cannot exist so close to the star, since the strong energy radiated by the star heats and ultimately destroys the dust grains. ESO PR Photo 03/08 ESO PR Photo 03b/08 The Region Around MWC 147 "We have performed detailed numerical simulations to understand these observations and reached the conclusion that we observe not only the outer dust disc, but also measure strong emission from a hot inner gaseous disc. This suggests that the disc is not a passive one, simply reprocessing the light from the star," explained Kraus. "Instead, the disc is active, and we see the material, which is just transported from the outer disc parts towards the forming star." ESO PR Photo 03/08 ESO PR Photo 03c/08 Close-up on MWC 147 The best-fit model is that of a disc extending out to 100 AU, with the star increasing in mass at a rate of seven millionths of a solar mass per year. "Our study demonstrates the power of ESO's VLTI to probe the inner structure of discs around young stars and to reveal how stars reach their final mass," said Stefan Kraus. More Information The authors report their results in a paper in the Astrophysical Journal ("Detection of an inner gaseous component in a Herbig Be star accretion disk: Near- and mid-infrared spectro-interferometry and radiative transfer modeling of MWC 147", by Stefan Kraus, Thomas Preibisch, Keichii Ohnaka").
ERIC Educational Resources Information Center
McNamara, Paul
2012-01-01
Two floors of the W. K. Hancock Library at the Australian National University (ANU) were refurbished in 2011 as part of a cooperative project between the library and the College of Science. The refurbishment, costing $5 million, was part of a much larger exercise involving the construction of four new science buildings around the Hancock Library.…
1994-07-01
Photo by Peter McGregor Comet Shoemaker-Levy 9 impacting Jupiter; impact of Fragment G of Comet Shoemaker-Levy on Jupiter. The fireball is seen 12 minutes after impact at 2.34 microns. The impact A site is seen on the oposite limb of the planet. Image at 2.34 microns with CASPIR by Peter McGregor ANU 2.3m telescope at Siding Spring. (JPL Ref; P-44419)
International Research and Development in Systems Biology
2005-10-01
Poolla K., P. Khargonekar, A. Tikku, J. Krause , and K. Nagpal. 1994. A Time-Domain Approach to Model Validation. IEEE Trans Automat Contr 39: 951...Another European researcher modeling chemotaxis and cell motility is Wolfgang Alt (Bonn, Germany), although the panel did not visit his laboratory...Center/Hepatocyte Project Heidelberg, Germany Otmar Wiestler, Siegfried Neumann, Ursula Klingmüller, Willi Jager, Wolfgang Driever, Matthias Reuss
Definition of Research Needs to Address Airport Pavement Distress in Cold Regions
1989-05-01
2318 RODNEY A. 03/04/85 ALLIANCE AIRPORT PO DRAWER D ALLIANCE NE 69301 ACE NC BAUER 308-762-5400 WOLFGANG 03/25/85 HALL COUNTY REGIONAL AIRPORT ROUTE 3...NW WINTER 206-346-7380 JEFF 03/05/85 SEA-TAC INT’L. AIRPORT SEATTLE WA 98188 ANN MW KRAUSE 206-433-5410 ART 03/05/85 GRANT COUNTY AIRPORT TERMINAL
1989-07-26
Results as ’Positive’ [A. Krause ; Vienna TV 12 Jul] 33 JPRS-TAC-89-030 26 JULY 1989 FEDERAL REPUBLIC OF GERMANY Foreign Minister Genscher Hails...member and Central Committee secretary, briefed Guenther Maleuda, chairman of the Democratic Peasants Party of Germany [DBD]; Wolfgang Heyl, deputy... Wolfgang Georgi commentary: "NATO and Nuclear Disarmament"] [Text] By accepting the U.S. proposal to carry out test inspections for the
Parallel and Distributed Systems for Probabilistic Reasoning
2012-12-01
work at CMU I had the opportunity to work with Andreas Krause on Gaussian process models for signal quality estimation in wireless sensor networks ...we reviewed the natural parallelization of the belief propagation algorithm using the synchronous schedule and demonstrated both theoretically and...problem is that the power-law sparsity structure, commonly found in graphs derived from natural phenomena (e.g., social networks and the web
WIS Implementation Study Report. Volume 2. Resumes.
1983-10-01
WIS modernization that major attention be paid to interface definition and design, system integra- tion and test , and configuration management of the...Estimates -- Computer Corporation of America -- 155 Test Processing Systems -- Newburyport Computer Associates, Inc. -- 183 Cluster II Papers-- Standards...enhancements of the SPL/I compiler system, development of test systems for the verification of SDEX/M and the timing and architecture of the AN/U YK-20 and
The Impact of Army and Family Factors on Individual Readiness
1993-08-01
families. While, in general , individual characteristics were more important in the determination of soldieL. readiness than famlily characteristics...affected indi- vidual readiness, in general , family-related variables had higher impact on soldier intention to remain in the Army after their cur- rent...installations. This survey was designed to provide information related to Army policy/program questions based on prior and current research anu to generate new
$200,000 Grants Awarded to CCR Researchers for HIV/AIDS Studies | Poster
By Nancy Parrish, Staff Writer Earlier this year, the Office of AIDS Research (OAR) awarded two, two-year grants of $200,000 each to Anu Puri, Ph.D., and Robert Blumenthal, Ph.D., both of the Center for Cancer Research (CCR) Nanobiology Program, and to Eric Freed, Ph.D., of the HIV Drug Resistance Program, for their research on potential new treatments for HIV.
A new fast-cycling system for AMS at ANU
NASA Astrophysics Data System (ADS)
De Cesare, M.; Fifield, L. K.; Weisser, D. C.; Tsifakis, D.; Cooper, A.; Lobanov, N. R.; Tunningley, T. B.; Tims, S. G.; Wallner, A.
2015-10-01
In order to perform higher precision measurements, an upgrade of the ANU accelerator is underway. Fast switching times on the low-energy side, with maximum settling times of 30 ms, are achieved by holding the injector magnet field constant while changing the energy of the different isotopes by changing the pre-acceleration voltage after the ion source. Because ions of the different isotopes then have different energies before injection, it is necessary to adjust the strength and steering of the electrostatic quadrupole lens that focusses the beam before entry into the accelerator. First tests of the low-energy system will be reported. At the high energy end, a larger vacuum box in the analyzing magnet has been designed, manufactured and installed to allow the transport of differences in mass as large as 10% at constant terminal voltage. For the cases where more than one isotope must be transported to the detector an additional refinement is necessary. If the accelerator voltage is to be kept constant, then the trajectories of the different isotopes around both the analyzing and switching magnets must be modified. This will be achieved using bounced electrostatic steerers before and after the magnets. Simulations have been performed with the ion optic code COSY Infinity to determine the optimal positions and sizes of these steerers.
Abundances of uranium, thorium, and potassium for some Australian crystalline rocks
Bunker, Carl Maurice; Bush, C.A.; Munroe, Robert J.; Sass, J.H.
1975-01-01
This report contains a tabulation of the basic radioelement and radiogenic heat data obtained during an Australian National University (ANU) - United States Geological Survey (USGS) heat-flow project, directed jointly by J. C. Jaeger (ANU) and J. H. Sass (USGS). Most samples were collected during the periods June through September, 1971 and 1972. The measurements were made subsequently by two of us (C. M. Bunker and C. A. Bush) using the gamma-ray spec trometric techniques described by Bunker and Bush (1966, 1967). Interpreting the spectra for quantitative analyses of the radioelements was accomplished with an iterative leastsquares computer program modified from one by Schonfeld (1966). Uranium content determined by gamma-ray spectrometry is based on a measurement of the daughter products of 226Ra. Equilibrium in the uranium-decay series was assumed for these analyses . Throughout the report, when U content is stated, radium-equivalent uranium is implied. The coefficient of variation for the accuracy of the radioelement data, when compared to ana lyses by isotope dilution and flame photometry is about 3 percent for radium-equivalent uranium and thorium and about 1 percent for potassium. These percentages are in addition to minimum standard deviations of about 0.05 ppm for U and Th, and about 0.03 percent for K.
1991-09-01
Maintaining Goal Congruence International Cooperation-the Next Generation ENDNOTES 1. Wolfgang Flume and David Swa, "British Aerospace-Leading...Program Management Questionnaire Report. Michael G. Krause , DSMC internal document, May 1989- 10. Bonn Seminar on Armaments cooperation, proceedings, w...Appendix K 154 International Cooperation-the Next Generation Dudney, Robert S., "The Electronics Industry Flume, Wolfgang , "Electronics for the Ger- Is
Points of Contact for Oceanographic Institutes in Europe and Russia
1993-05-20
Wolfgang dle Initial: t Name: Fennel Title: Dr. 40ompany: Institut fur Ostseeforschung Address 1: Warnemunde an der Universitat Rostock Address 2...Phone: Cellular: Category: physics Notes: fennel~physik iowarnemuende.dbp.de, Telex: 398516 do d Wolfgang Fijnaut Royal Netherlands Meteorological...34Phone: Fax: Home Phone: Cellular: Category: administration Notes: Head Krause AifredWegenerinstitut fur Polar u4p M_.peresforechun +49 (0) 471 4831 0
The Center of Gravity, Systemically Understood
2013-05-23
manner that gave him the time to pursue and destroy the retreating army. Centuries later, another great captain – Napoléon Bonaparte – employed...Jena-Auerstadt 1806 In 1806, Napoléon Bonaparte became the first operational artist in the history of modern war when he defeated the Prussian... Napoleon , Operational Art, and the Jena Campaign,” in Historical Perspectives of the Operational Art, ed. Michael D. Krause and R. Cody Phillips
An Annotated Reading List for Concurrent Engineering
1989-07-01
The seven tools are sometimes referred to as the seven old tools.) -9- Ishikawa , Kaoru , What is Total Quality Control? The Japanese Way, Prentice-Hall...some solutions. * Ishikawa (1982) presents a practical guide (with easy to use tools) for implementing qual- ity control at the working level...study of, :-, ieering for the last two years. Is..ikawa, Kaoru , Guide to Quality Control, Kraus International Publications, White Plains, NY, 1982. The
The Role of Concurrent Engineering in Weapons System Acquisition
1988-12-01
checx sheets, Pareto diagrams, graphs, control charts, and scatter diagrams. Kaoru Iskilkawa, Guide to Qualiy Conmi, Asian Productivity Organization...Dewing [3 !,Juran [141, and Ishikawa [l). Managers in the United States and Japan have used techniques of statistics to measure performance and they have...New York (1962). 15. Kaoru Ishkawa, Guide to Quall’y Control, KRAUS International Publications, White Plains, NY (1-982). 16. Robert H. Hayc,%. St
1983-05-13
Heincker Ernst H Jaeger AG1007 Rolf -Helmut Kraus Department Engineering Mechanics Messerschmitt Bolkow Blohm Bundesamt fur Wehrtechnik USAF Academy...Septenber 1981. I ii. Laboratory data is essential for (2) Dass, W.C., Merkle , D.H., a.nd Bratton, modeling soil, but it must be extrapolated to J.L
1997-04-01
m ^ also include the provision of care in combat or deployed situations. Patient Education (patient teaching): the process of influencing patient...make important contiibutions to cost containment in the area of health care (Damrosch, 1991). Patient education and tobacco cessation intervention...Krause, 1995; Pender & Pender, 1987; Sparics, 1995). For successful patient education to occur, motivational factors of the patient related to
2006-09-01
IMPLEMENTATION OF AN INTERACTIVE UNIFORM REGULATIONS MANUAL FOR THE UNITED STATES MARINE CORPS by Michael H. Villar Carsten Krause...SUBTITLE: Development and Implementation of an Interactive Uniform Regulations Manual for the United States Marine Corps 6. AUTHOR(S) Michael H. Villar...IMPLEMENTATION OF AN INTERACTIVE UNIFORM REGULATIONS MANUAL FOR THE UNITED STATES MARINE CORPS Michael H. Villar Major, United States Marine Corps B.A
Critical discussion on the "observed" water balances of five sub-basins in the Everest region
NASA Astrophysics Data System (ADS)
Chevallier, P.; Eeckman, J.; Nepal, S.; Delclaux, F.; Wagnon, P.; Brun, F.; Koirala, D.
2017-12-01
The hydrometeorological components of five Dudh Koshi River sub-basins on the Nepalese side of the Mount Everest have been monitored during four hydrological years (2013-2017), with altitudes ranging from 2000 m to Everest top, areas between 4.65 and 1207 km², and proportions of glaciated areas between nil and 45%. This data set is completed with glacier mass balance observations. The analysis of the observed data and the resulting water balances show large uncertainties of different types: aleatory, epistemic or semantic, following the classification proposed by Beven (2016). The discussion is illustrated using results from two modeling approaches, physical (ISBA, Noilhan and Planton, 1996) and conceptual (J2000, Krause, 2001), as well as large scale glacier mass balances obtained by the way of a recent remote sensing processing method. References: Beven, K., 2016. Facets of uncertainty: epistemic uncertainty, non-stationarity, likelihood, hypothesis testing, and communication. Hydrological Sciences Journal 61, 1652-1665. doi:10.1080/02626667.2015.1031761 Krause, P., 2001. Das hydrologische Modellsystem J2000: Beschreibung und Anwendung in groen Flueinzugsgebieten, Schriften des Forschungszentrum Jülich. Reihe Umwelt/Environment; Band 29. Noilhan, J., Planton, S., 1989. A single parametrization of land surface processes for meteorological models. Monthly Weather Review 536-549.
KEGS Discovery of 9 Supernova Candidates in the K2 Campaign 17 field with Pan-STARRS PS1
NASA Astrophysics Data System (ADS)
Smith, K. W.; Rest, A.; Tucker, B. E.; Garnavich, P. M.; Margheim, S.; Kasen, D.; Olling, R.; Shaya, E.; Narayan, G.; Villar, A.; Forster, F.; Mushotzky, R.; Zenteno, A.; James, D.; Smith, R. Chris; Dotson, J. L.; Barentsen, G.; Gully-Santiago, M.; Smartt, S. J.; Wright, D. E.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Schultz, A.; Magnier, E.; Waters, C.; Bulger, J.; Wainscoat, R. J.
2018-05-01
We report the following transients discovered by Pan-STARRS1 during a targeted search of the Kepler Campaign 17 field as part of the K2 Extragalactic Survey (KEGS) for Transients (see http://www.mso.anu.edu.au/kegs/ ) Information on the Pan-STARRS Survey for Transients is available at http://star.pst.qub.ac.uk/ps1threepi/ (see Huber et al. ATel #7153).
Deciphering the balkan Enigma: Using History to Inform Policy
1993-03-01
University Press, 1973. After long experience with German interference in Serbian/Yugoslav affairs (1878, 1908, 1914 - 1918 ) it should not be surprising that... 1914 - 1918 , ed. Djordjevicý, Santa Barbara: CLID Books, 1980. 151. James Gow, "Deconstructing Yugoslavia," Survival, Vol. 33, Nc. 4, July-August 1992, p...of political institutions witnin tine Balkans anu io0w these political dev, ’ýpments intluence current events. Historical perspective gained is used
2011-12-01
ofthe Operational Art, by Michael 0 . Krause and Cody R. Phillips (Washington D.C.: Center of Military History, 2007), 444. The level of multinational...Werner, and Wolfgang Fett. Bericht uber das gemeinsame Berliner Colloquium 2009 von Clausewitz-Gesellschafi und Bundesakademie fiir Sicherheilspolitik...Vol. 5, in Die Jahrbiicher der C/ausewitz-Gesellschafi e. V. - Jahrbuch 2009, by Werner Baach and Wolfgang Fett, 13-24. Hamburg: C lausewitz
European Science Notes Information Bulletin Reports on Current European/Middle Eastern Science
1989-04-01
provided byJ. Kreuter (In- skin. The purpose was to minimize one of the problems stitutc for Pharmaceutical Chemistry, Johann Wolfgang associated with...robotics, and database issues. papers by general category. The organizer of the meeting was Professor Dr. Wolfgang Strasser of the Wilhelm Schickard...prob- dural Models" lems because the active points on the boundary arc more . N. Yaramanoglu (coauthors F.-L. Krause , M. Bienert, difficult to find. A
Managing the Reputation of DHS and its Components
2009-06-01
Neutral Reputations,” 129. 70 Ibid., 125. 71 Hans Krause Hansen, Roy Langer, and Dorte Salskov-Iversen, “Managing Political Communications...Rossow, “The Delphi Process in Marketing Decision Making,” Journal of Marketing Research 8, no. 4 (1971): 444. 153 Ibid. 154 Wolfgang Scholl...May 8, 2006): 45. Santoli, Michael. “They’ve Got Class.” Barron’s 87, no. 37 (September 10, 2007): 33-36. Scholl, Wolfgang , Christine Konig, Bertolt
Next Generation Nanotechnology Assembly Fabrication Methods: A Trend Forecast
2008-01-01
accessed: January 12, 2007. 33 Eck, Wolfgang , et al. “Generation of two- and three-dimensional nanostructures by electron beam lithography on self...nano/reports/mcr_05-0526_intpersp_nano.pdf, accessed on January 15, 2007. 62 Ibid. 63 Ibid. 64 Ibid. 65 Ibid. 66 Luther, Wolfgang ...Defense Merrick E. Krause , May 2002 29 Death by a Thousand Cuts: Micro-Air Vehicles in the Service of Air Force Missions Arthur F. Huber II, June
1981-09-01
247-1 Moffett Field, CA 94035li W. Kordulla "NASA-Ames Research Center Mail Stop 202A-1 "Moffett Field, CA 94035 -. E. Krause Aerodynamiaches Inatitut...University Stanford, CA 94305 Wolfgang Rodi SFB 80 Universitat Karlsruhe Kaiserstrasse 12 D-75 Karlsruhe 1, W. Germany Robert Rogallo NASA-Ames Research Cntr
Resource-Bounded Information Acquisition and Learning
2012-05-01
candidate features arrive one at a time, and the learner’s task is to select a ‘best so far’ set of features from streaming features. Krause et al...on Artificial Intelligence. [31] Gatterbauer, Wolfgang . Estimating required recall for successful knowledge acquisition from the web. In Proceedings of...the 15th international conference on World Wide Web (New York, NY, USA, 2006), WWW ’06, ACM, pp. 969– 970. [32] Gatterbauer, Wolfgang . Rules of thumb
European Science Notes Information Bulletin Reports on Current European/ Middle Eastern Science
1991-12-01
Symposium 89, F.-L. Krause , H. Jansen, eds., held in Berlin, NY:ASME. FRG November 1989. Hansmann, W. November. 1985. Interactiver entwurf und Nowacki, H...8217 Smoothing of Multipatch Bzier Surfaces - Curvature Approximation and Knot Removal for Wolfgang Schwarz, EDS GmbH, FRG (A). Handling Scattered Data - Bernd...Physical Oceanography research vessel. The Institute has three CTDs which have been used to obtain a very complete hydrographic series Dr. Wolfgang F
Practical Software Measurement: Measuring for Process Management and Improvement,
1997-04-01
Ishikawa , Kaoru . Guide to Quality Control, Second Revised Edition. White Plains, N.Y.: UNIPUB-Kraus International Publications, 1986. CMU/SEI-97...begin, you may want to assemble a group of people who work within the process to brainstorm possible reasons for the unusual behavior. Ishikawa charts...control limits and center line. • Cause-and-effect diagrams (also know as Ishikawa charts) allow you to probe for, map, and prioritize a set of factors
Assessing Stress Responses in Beaked and Sperm Whales in the Bahamas
2011-09-30
for T3 will follow Wasser et al. (2010). Fecal hormone assay results will be used to develop baseline levels for all five hormones in Blainville’s...Hunt K.E., Rolland R.M., Kraus S.D., and Wasser S.K. 2006. Analysis of fecal glucocorticoids in the North Atlantic right whale (Eubalaena glacialis... Wasser , S.K. 2005. Assessing reproductive status of right whales (Eubalaena glacialis) using fecal hormone metabolites. General and Comparative
Techniques for Exploiting Unlabeled Data
2008-10-01
Moore, Ar- jit Singh, Jure Leskovec, Stano Funiak, Andreas Krause, Gaurav Veda, John Lang- ford, R. Ravi, Peter Lee, Srinath Sridhar, Virginia Vassilevska...information. However, in the past few decades for many tasks the supply of information has outpaced our ability to effectively utilize it. For example in...function which contains kernel functions as a sub-class and show that effective learning can be done in this framework. Although the work in this area is
European Science Notes Information Bulletin.
1992-12-01
the rest from competitive research "not free" in their expression in or out of class, funded by Bonn or the EC. The one eastie I had a chance to talk...is a long way off because tions in Lead Time at Volvo Based on Restructur- the walls are high and people are hard to change. ing the Design Process...linked to each other. ( Energy flowing from Prof. Krause. out of one element can flow into
Inlet Reservoir Model. Part 2: PC-Interface
2011-12-01
2008); and Zarillo and Kraus (2003). Figure 1 shows a schematic of an inlet system within the IRM with various types of reservoirs (e.g., channel...ERDC/CHL CHETN-IV-xx 2 Knowledge of engineering activities within the inlet system (e.g., dredging of a deposition basin or dredged channel...there to the Shore, S. As the first reservoir in the system , E, fills and its volume increases closer to the equilibrium (identified for all
1999-06-01
Department of Biochemistry and Molecular Biology at Cornell University in Ithaca, NY. Dr. Gwendal Lazennec, a Postdoctoral Researcher on this work...Ph.D.) En, Julie Hoeksema, Jason Keller, Anne Kraus, William Lee (Ph.D.) Krueger, Kristopher Lazennec, Gwendal (Ph.D.) Mclnerney, Eileen (Ph.D...Receptors Containing Amino Acid Substitutions for Tyrosine 537 in the Receptor Protein Karen E. Weis, Kirk Ekena, James A. Thomas, Gwendal Lazennec
Delamuta, Jakeline Renata Marçon; Ribeiro, Renan Augusto; Gomes, Douglas Fabiano; Souza, Renata Carolina; Chueire, Ligia Maria Oliveira
2015-01-01
Bradyrhizobium pachyrhizi PAC48T has been isolated from a jicama nodule in Costa Rica. The draft genome indicates high similarity with that of Bradyrhizobium elkanii. Several coding sequences (CDSs) of the stress response might help in survival in the tropics. PAC48T carries nodD1 and nodK, similar to Bradyrhizobium (Parasponia) ANU 289 and a particular nodD2 gene. PMID:26383651
Two-Photon Porphyrin Core Dendrimers for Optical Power Limiting
2006-09-30
macrocycle as compared to centro- symmetric porphyrins. Lowering of the symmetry relaxes the parity selection rules for 2PA, thus making the Soret band...collection of information is estimated to average 1 hour per response, including the time for reviewing instr* - - a 9 www, yen. .c. my anu maintaining...and polymers [2]. 3. We have completed a detailed study of 2PA in symmetrical and asymmetrical (push-pull) phthalocyanines [3,4,5]. 4. We have
1974-07-01
elec- Materials se: trode materials and associ- operational ated conductors. 2.5.1 General. H" (02) Materials resources Technoeconomic analysis - None...Advanced Energy Systems Using New Fnels VIII Correlation and Analysis of Materials Requirements IX Research Recommendations and Priorities The authois...of government and industrial organizal ions who gave us the benefit of their knowledge and experience. iv VIII CORRELATION ANU ANALYSIS OF MATERIALS
1988-09-01
FishesS and Invertebrates (Pacific Southwest) CALIFORNIA SEA MUSSEL AND BAY MUSSEL Cn Coastal Ecology Group *Fish and Wildlife Service Waterways...September 1988 Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest) CALIFORNIA SEA MUSSEL...AND BAY MUSSEL by William N. Shaw Fred Telonicher Marine Laboratory Humboldt State University Trinidad, CA 95570 Thomas J. Hassler U.S. Fish anu
Effect of soiling in CPV systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vivar, M.; Herrero, R.; Anton, I.
2010-07-15
The effect of soiling in flat PV modules has been already studied, causing a reduction of the electrical output of 4% on average. For CPV's, as far as soiling produces light scattering at the optical collector surface, the scattered rays should be definitively lost because they cannot be focused onto the receivers again. While the theoretical study becomes difficult because soiling is variable at different sites, it becomes easier to begin the monitoring of the real field performance of concentrators and then raise the following question: how much does the soiling affect to PV concentrators in comparison with flat panels?'more » The answers allow to predict the PV concentrator electrical performance and to establish a pattern of cleaning frequency. Some experiments have been conducted at the IES-UPM and CSES-ANU sites, consisting in linear reflective concentration systems, a point focus refractive concentrator and a flat module. All the systems have been measured when soiled and then after cleaning, achieving different increases of I{sub SC}. In general, results show that CPV systems are more sensitive to soiling than flat panels, accumulating losses in I{sub SC} of about 14% on average in three different tests conducted at IES-UPM and CSES-ANU test sites in Madrid (Spain) and Canberra (Australia). Some concentrators can reach losses up to 26% when the system is soiled for 4 months of exposure. (author)« less
More Intelligent Gas Turbine Engines (Des turbomoteurs plus intelligents)
2009-04-01
Group 128. by Dennis Culley, NASA Glenn Research Center Sanjay Garg, NASA Glenn Research Center S.-J. Hiller, MTU Aero Engines GmbH Wolfgang Horn...in Swirled Gas Turbine Combustors”, AIAA-2005-116. [2.90] Seume, J.R., Vortmeyer, N., Krause , W., Hermann, J., Hantschk, C.-C., Zangl, P., Gleis, S...TR-AVT-128 8 - 1 Chapter 8 – SUMMARY AND RECOMMENDATIONS by Sanjay Garg (NASA Glenn Research Center), Wolfgang Horn and S.-J. Hiller (MTU
Theater Nuclear Force Modernization as an Issue in West German Politics, 1977-1980
1980-12-01
surrounding the deployment of the Davy Crockett provide a case in point. According to Wolfgang Heisenberg, these weapons 21 . -- ... would require quite...serving the SPD parliamentary group; the second was compiled by Wolfgang Pordzik of the Konrad Adenauer Foundation in Bonn, an organization associated...introduced in ’isarmmament talks. A number of other SPD members agreed with Bahr’s analysis. "Christian Krause wzote on the Soviet threat in Vorwarts
1985-01-01
CECOM, Ft. Monmouth, N.J. ".,.-- .,. Kurth Krause , Intermetrics, Inc., Huntington Beach, CA. Benjamin Martin, Atlanta University, Atlanta, GA. Isabel...Teledyne Brown, Tinton Falls, N.J. Paul Wolfgang , Computer Science Corp., Moorestown, N.J. - TECHNICAL SESSIONS - " Wednesday, March 20, 1985 9:00 am...STRATEGIES J. McGlynn, CENTACS, CECOM, Ft. Mon- AND TECHNIQUES mouth, NJ ............................. 178 Chairperson: Paul Wolfgang , Computer Science
Metal Injection Molding for Superalloy Jet Engine Components
2006-05-01
single vanes. The vanes are subject to high vibration stresses and thus require reliable fatigue strength. Therefore the quality of the material must meet...Injection Molding for Superalloy Jet Engine Components 9 - 12 RTO-MP-AVT-139 UNCLASSIFIED/UNLIMITED UNCLASSIFIED/UNLIMITED MTU AeroEngines copyright...Sikorski Max Kraus Dr. Claus Müller MTU Aero Engines GmbH Munich, Germany 15.05. - 17.05.2006 MTU AeroEngines copyright ©2 AVT – 139 on “Cost Effective
Transrectal Near-Infrared Optical Tomography for Prostate Imaging
2009-03-01
using a directional transurethral ultrasound applicator,” J Magn Reson Imaging., 15(4), 409-17. Iftimia N , and Jiang H (2000), “Quantitative... N , Carroll PR, Flax J, Blumenfeld W, and Folkman J (1993), "Tumor angiogenesis correlates with metastasis in invasive prostate carcinoma," Am J...34 JAMA. 281, 1591-1597 (1999). 6. A. C. Loch, A. Bannowsky, L. Baeurle, B. Grabski, B. König, G. Flier, O. Schmitz-Krause, U. Paul , and T. Loch
Examination of Various Methods Used in Support of Concurrent Engineering
1990-03-01
1989. F.Y.I. Drawing a2Ther Productivity. Industrial Engineering 21: 80. Ishi82 Ishikawa , Kaoru . 1982. Guide to Quality Control. White Plains, NY: Kraus...observe it in practice have an easier time identifying the different methods or tech- niques (such as the Ishikawa tools) used than understanding the...simple histogram to show what prob- lems should be attacked first. Cause and Effect Diagrams Sometimes called the fishbone or Ishikawa diagrams-a kind
Ultralow Loss Optomechanics Using Diagmagnetically Levitated Drops of Liquid Helium
2015-03-12
Instruments. The magnet coils ( crossed diagonal lines) enclose a bore that is a vacuum space, and can be accessed from room temperature. A similar magnet and...Review Letters 91, 130401 (2003). 5 Oriol Romero-Isart, Anika C. Pflanzer, Florian Blaser, Rainer Kaltenbaek, Nikolai Kiesel, Markus Aspelmeyer, J...State” Nature 475, 359 (2011). 8 Jasper Chan, T. P. Mayer Alegre, Amir H. Safavi-Naeini, Jeff T. Hill, Alex Krause, Simon Gröblacher, Markus Aspelmeyer
Post-Deployment Reintegration Measure: Psychometric Replication and Preliminary Validation Results
2006-02-01
soudain au pays et la reprise des fonctions et activités « normales » peuvent engendrer un stress significatif chez le personnel militaire. Notre...Contexte : Après un séjour prolongé outre-mer, le retour soudain aux fonctions et activités normales peut engendrer un stress significatif chez...Johnson et al ., 1997; Wilson & Krause, 1985). For instance, participants in a focus group study of Canadian Forces (CF) personnel indicated that it
Post-deployment Reintegration Measure: Psychometric Replication and Preliminary Validation Results
2006-02-01
soudain au pays et la reprise des fonctions et activités « normales » peuvent engendrer un stress significatif chez le personnel militaire. Notre...Contexte : Après un séjour prolongé outre-mer, le retour soudain aux fonctions et activités normales peut engendrer un stress significatif chez...Johnson et al ., 1997; Wilson & Krause, 1985). For instance, participants in a focus group study of Canadian Forces (CF) personnel indicated that it
2012-01-01
including; Alzheimer’s disease (Mac- cioni et al. 2009), Parkinson’s disease (Hirsch and Hunot 2009), spinal cord injury (Chan 2008), multiple sclerosis ...states such as multiple sclerosis (Kraus et al. 2000), human immunodeficiency virus dementia (Fischer- Smith et al. 2001), and meningitis (Cauwels et al...Immunologic mechanisms of multiple sclerosis . Neuroi- maging Clin. N. Am. 18, 577–588. Gaylord K. M. (2006) The psychosocial effects of combat: the frequently
An ecodesign method for reducing the effects of hazardous substances in the product lifecycle
NASA Astrophysics Data System (ADS)
Simanovska, J.; Valters, K.; Bažbauers, G.; Luttropp, C.
2012-10-01
Growing evidence on the indoor and outdoor pollution caused by the flow of man-made products urges that the content and leaching of hazardous substances from products be minimised. One of the ways to reduce the potential adverse impacts caused by these substances could be via ecodesign - i.e. through the consideration of lifecycle-related environmental aspects during the product development. The authors’ review of the existing ecodesign methods highlights the weakness of these methods in identifying and assessing the health-related and environmental impacts of hazardous substances contained in products, especially with regard to the exposure assessment. Therefore, a new, semi-quantitative screening ecodesign method applicable for different types of products has been developed. The method ranks the most severe hazards based on the classification according to the Globally Harmonised System together with the exposure evaluation as well as integrates the aspects of material efficiency. This method is suitable for use in the product development process, requiring decisions to be made based on limited information while integrating the main principles of a scientific risk assessment for chemicals. Application of the method is demonstrated with a case study on products made of plywood. The method makes it possible to identify the needs for and elaboration of ecodesign proposals, and fosters communication and information exchange throughout the supply chain.
Delamuta, Jakeline Renata Marçon; Ribeiro, Renan Augusto; Gomes, Douglas Fabiano; Souza, Renata Carolina; Chueire, Ligia Maria Oliveira; Hungria, Mariangela
2015-09-17
Bradyrhizobium pachyrhizi PAC48(T) has been isolated from a jicama nodule in Costa Rica. The draft genome indicates high similarity with that of Bradyrhizobium elkanii. Several coding sequences (CDSs) of the stress response might help in survival in the tropics. PAC48(T) carries nodD1 and nodK, similar to Bradyrhizobium (Parasponia) ANU 289 and a particular nodD2 gene. Copyright © 2015 Delamuta et al.
2006-07-27
9 10 Technical horizon sensors Over the past few years, a remarkable proliferation of designs for micro-aerial vehicles (MAVs) has occurred... photodiode Fig. 15 Fig. 14 Sky scans with a GaP UV pho to dio de a lo ng three vert ical paths. A ngle o f v iew 30 degrees, 50% clo ud co ver, sun at...Australia Email: gert.stange@anu.edu.au A biomimetic algorithm for flight stabilization in airborne vehicles , based on dragonfly ocellar vision
2011-03-09
anu.edu.au Nocturnal visual orientation in flying insects: a benchmark for the design of vision-based sensors in Micro-Aerial Vehicles Report...9 10 Technical horizon sensors Over the past few years, a remarkable proliferation of designs for micro-aerial vehicles (MAVs) has occurred...possible elevations, it may severely degrade the performance of sensors by local saturation. Therefore it is necessary to find a method whereby the effect
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shortis, M.R.; Johnston, G.H.G.
1996-08-01
Close range photogrammetry is a sensing technique that allows the three-dimensional coordinates of selected points on a surface of almost any dimension and orientation to be assessed. Surface characterizations of paraboloidal reflecting surfaces at the ANU using photogrammetry have indicated that three-dimensional coordinate precisions approach 1:20,000 are readily achievable using this technique. This allows surface quality assessments to be made of large solar collecting devices with a precision that is difficult to achieve with other methods.
Information Resource Management for Naval Shore Activities: Concepts and Implementation Strategy.
1984-09-01
with accurate inorl atn, at the right time and a the lowest cost. (Ref. 21: p. 15) *" managing the i0formation resource essentially means gathering...US Lf eczcJu 21 =guZ~wuLU Essential in the implementation of Information -" ]Resource anagement, is a clear understanding of the rela- tionships...of determins.ng the needs of the user of a structure anu then d9signing to meet those needs as effectively as possIble within ecnomic and
DOE Office of Scientific and Technical Information (OSTI.GOV)
Manikandan, M.; Santhosh, M.; Rajeswarapalanichamy, R., E-mail: rrpalanichamy@gmail.com
Ab initio calculations are performed to investigate the structural stability, electronic structure and mechanical properties of actinide carbides AnC (An=U, Np) for three different crystal structures, namely NaCl, CsCl and ZnS. Among the considered structures, NaCl structure is found to be the most stable structure for these carbides at normal pressure. A pressure induced structural phase transition from NaCl to ZnS is observed. The electronic structure reveals that these carbides are metals. The calculated elastic constants indicate that these carbides are mechanically stable at normal pressure.
1989-07-20
Krause , Phys. Stat. Sol. (a) 102, 443 (1987) 2) \\1. Tajima, in "Defects and Properties of Semiconductors: Defect Engineering", edited by J. Chikawa (Tokyo...illustrate that the newly developed electron optical column satisfies all the requirements for internal measurements on VLSI circuits. (1] E. Wolfgang ...JEME29, rue Jeanne Marvig 13397 MARSEILLE CEDE-X 13 31400 TOULOUSE FRANCE FRANCE PICQUERA-S Javier- SCHROTER Wolfgang Dpto de Fisica de Materiales IV
2003-08-01
Gerhard Braun, Dr. Rudolf Edse, Dr. Wolfgang Noeggerath, Hans Rister, and Dr. Theodor Zobel. (Dr. von Braun and the four other rocket specialists...Heinrich Albers, Herman Bottenhorn, Gerhard Krause , Dr. Ernst Kugel, and Hermann Nehlsen to Loewy Hydropress, Inc., in New York, while Dr. Claus...March 1948, Air Materiel Command maintained the Watson- and Cambridge-assigned German scientists at status quo, but added Dr. Wolfgang Pfister the next
1988-05-13
Encapsulants H6rnig, Jahanna Kron and Wolfgang Hepp 2:40 B41 Recent Advances in Organosiloxane Copolymers 3:00 BREAK James E. McGrath New Developments in the...Mobility of H2 ontaining Oligomeric Siloxanes by Si-NMR S 10:10 B48 Syntheses and Reactions N. Heo, R. Krause and R. Kos- of Uniform Size Poly...Technical University Graz Stremayrgasse 16 A-8010 Graz, Austria Kirsten Hinrichs Department of Chemistry University of Wisconsin-Madison Wolfgang
[Rudolf Krauss, Giovanni Noe and a flash of infectious diseases in Chile, 1930].
Ledermann, Walter
2015-06-01
When there were giants on the earth, two of them, Rudolf Kraus and Giovanni Noe, met at the ancient Bacteriological Institute of Chile, and founded together a journal representing the principles of the institution. A nostalgic glance over the papers published therein for these so named giants lets us know a little about the study of infectious diseases in the thirties, when tuberculosis and malaria were two of the biggest problems for the world's public health... then and now.
2012-10-23
Naeini A H, Hill J T, Krause A, Groblacher S, Aspelmeyer M and Painter O 2011 Nature 478 89 [14] Siegman A E 1986 Lasers (Sausalito, CA: University... laser rate equation theory and experimental verification 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...coherent mechanical oscillators: the laser rate equation theory and experimental verification J B Khurgin1, M W Pruessner2,3, T H Stievater2 and W S
Military Doctrine, and Maxims of Napoleon, A Bibliography of Periodical Articles.
1984-10-01
0041-770X. ....- S. . ..... -79 PART II - DOCTRINE -1. USA ANDERSON, NORMAN J. "A Statement of Doctrine," NCG, 47:10. November 1963. "Army 86...Process," MILRVW, 64:46-57, January 1984. KRAUSE, MICHAEL D..~ - "Arthur L. Wagner : Doctrine and Lessons from the Past," MILRVW, 58:53-9, November...June 1927. b. Democratic Republic of Germany (DDR). BELL, RAYMOND E. "Armor Development in the Weimar Republic," MILRVW, 47:12-7, March 1967. c
An Optimal Dissipative Encoder for the Toric Code
2014-01-16
Topological quantummemory J. Math. Phys. 43 4452–505 [6] Diehl S, Micheli A, Kantian A, Kraus B, Büchler H P and Zoller P 2008 Quantum states and phases in...Diehl S, Kantian A, Micheli A and Zoller P 2008 Preparation of entangled states by quantum Markov processes Phys. Rev. A 78 042307 [12] Marvian I 2013...Information Theory (Cambridge: Cambridge University Press) [20] Wolf M and Cirac J I 2008 Dividing quantum channels Commun. Math. Phys. 279 147 11
Compendium of Dental Residents’ Research Projects and Literature Reviews for 1989
1990-05-01
K. Krause, Major, USAF, DC The effectiveness of three immersion disinfectants: Chlorine dioxide, 2% glutaraldehyde, and 5.25% sodium hypochlorite was...5.25% sodium hypochlorite disinfectants also met the same standards of effectiveness at 10 and 5 minutes, respectively. 89 26 05 THE CLINICAL EFFECT...Solutions Time Temp Culture Culture Culture Sporicidin (Control) 10 min 240C 20 0 0 Sodium Hypochlorite 1 min 370C 20 0 0 Alcide Expore 2 min 370C 20 1
Solid Phase Synthesis of Polymacromer and Copolymacromer Brushes
2012-04-25
between immiscible polymers, which dictates the volume in which the interfacial reaction can occur, depends on the nature of thermodynamic interactions...Y.; Beers , K. L.; Byrd, H. C. M.; VanderHart, D. L.; Washburn, N. R. J. Am. Chem. Soc. 2004, 126, 3472−3476. (4) Merrifield, R. B. J. Am. Chem. Soc...Hartmann, L.; Krause, E.; Antonietti, M.; Boerner, H. G. Biomacromolecules 2006, 7, 1239−1244. (16) Mei, Y.; Beers , K. L.; Byrd, H. C. M.; VanderHart, D. L
2012-01-01
information-sharing and through systematic efforts to develop the supplier. These efforts can be direct involvement activities, such as kaizen events,24 24...Womack and Jones (1996) define kaizen as “Continuous, incremental improvement of an activity to create more value with less muda. Also called point... kaizen and process kaizen .” They define muda as “any activity that consumes resources but creates no value,” i.e., waste. Figure 2.2 Krause and
Laboratory Study on Macro-Features of Wave Breaking Over Bars and Artificial Reefs
1990-07-01
Prototype and Model Conditions of Case CE400 ( Pilot Test ) . 72 7 List of Design Parameters for Base Tests ... ........... . 72 8 List of Design Parameters...bar configurations, and the procedure was repeated. Pilot test 112. A pilot test was performed as a trial of the methodology and vali- dation of the...criterion on bar depth given by Larson and Kraus (1989) prior to actual testing . In this pilot test , the wave conditions and equilibrium bar formed in a
In vitro antiplasmodial activity of plants used in Benin in traditional medicine to treat malaria.
Bero, Joanne; Ganfon, Habib; Jonville, Marie-Caroline; Frédérich, Michel; Gbaguidi, Fernand; DeMol, Patrick; Moudachirou, Mansourou; Quetin-Leclercq, Joëlle
2009-04-21
The aim of the study was to evaluate the in vitro antiplasmodial activity of crude extracts of 12 plant species traditionally used in Benin for the treatment of malaria in order to validate their use. For each species, dichloromethane, methanol and total aqueous extracts were tested. The antiplasmodial activity of extracts was evaluated using the measurement of the plasmodial lactate dehydrogenase activity on chloroquine-sensitive (3D7) and resistant (W2) strains of Plasmodium falciparum. The selectivity of the different extracts was evaluated using the MTT test on J774 macrophage-like murine cells and WI38 human normal fibroblasts. The best growth inhibition of both strains of Plasmodium falciparum was observed with the dichloromethane extracts of Acanthospermum hispidum DC. (Asteraceae) (IC(50)=7.5 microg/ml on 3D7 and 4.8 microg/ml on W2), Keetia leucantha (K. Krause) Bridson (syn. Plectronia leucantha Krause) (Rubiaceae) leaves and twigs (IC(50)=13.8 and 11.3 microg/ml on 3D7 and IC(50)=26.5 and 15.8 microg/ml on W2, respectively), Carpolobia lutea G.Don. (Polygalaceae) (IC(50)=19.4 microg/ml on 3D7 and 8.1 microg/ml on W2) and Strychnos spinosa Lam. (Loganiaceae) leaves (IC(50)=15.6 microg/ml on 3D7 and 8.9 microg/ml on W2). All these extracts had a low cytotoxicity. Our study gives some justifications for the traditional uses of some investigated plants.
Adaptive Quantum Control of Charge Motion in Semiconductor Heterostructures
NASA Astrophysics Data System (ADS)
Reitze, David
1998-05-01
Quantum control of electronic wavepacket motion and interactions using ultrafast lasers has moved from the conceptual stage to reality, in large part driven by advances in quantum control theory (R. J. Gordon and S. A. Rice, Ann. Rev. Phys. Chem. (1997), in press.) (M. Shapiro and P. Brumer, J. Chem. Soc. Faraday Trans. V93, 1263 (1997).) (D. Neuhauser and H. Rabitz, Acc. Chem. Res. V26, 496 (1993).) and experimental pulse shaping methods (A. M. Weiner, D. E. Leaird, G. P. Wiederrecht, and K. A. Nelson, Science V247, 412 (1990).) (A. Efimov, C. Schaffer, and D. H. Reitze, J. Opt. Soc. Am VB12, 1968 (1995).). Here, we apply these methods to controlling charge motion in semiconductor heterostructures. Control of coherent charge dynamics in heterostructures enjoys an advantage in that spatial potential profiles can be adjusted almost arbitrarily. Thus, control of charge motion can be exerted by tailoring both the temporal and spatial interactions of the charges with the controlling optical and static fields. In this talk, we demonstrate an experimental feedback loop which adaptively shapes fs pulses in a quantum contol pump-probe experiment, apply it to the control of coherent wavepacket motion in DC-biased asymmetric double quantum well(ADQW) structures, and compare to theoretical predictions of quantum control in ADQWs (N. M. Beach, D. H. Reitze, and J. L. Krause, submitted to Opt. Exp.) (J. L. Krause, D. H. Reitze, G. D. Sanders, A. Kuznetsov, and C. J. Stanton, to appear in Phys. Rev. B).
NASA Astrophysics Data System (ADS)
Halliwell, George R.
Vertical coordinate and vertical mixing algorithms included in the HYbrid Coordinate Ocean Model (HYCOM) are evaluated in low-resolution climatological simulations of the Atlantic Ocean. The hybrid vertical coordinates are isopycnic in the deep ocean interior, but smoothly transition to level (pressure) coordinates near the ocean surface, to sigma coordinates in shallow water regions, and back again to level coordinates in very shallow water. By comparing simulations to climatology, the best model performance is realized using hybrid coordinates in conjunction with one of the three available differential vertical mixing models: the nonlocal K-Profile Parameterization, the NASA GISS level 2 turbulence closure, and the Mellor-Yamada level 2.5 turbulence closure. Good performance is also achieved using the quasi-slab Price-Weller-Pinkel dynamical instability model. Differences among these simulations are too small relative to other errors and biases to identify the "best" vertical mixing model for low-resolution climate simulations. Model performance deteriorates slightly when the Kraus-Turner slab mixed layer model is used with hybrid coordinates. This deterioration is smallest when solar radiation penetrates beneath the mixed layer and when shear instability mixing is included. A simulation performed using isopycnic coordinates to emulate the Miami Isopycnic Coordinate Ocean Model (MICOM), which uses Kraus-Turner mixing without penetrating shortwave radiation and shear instability mixing, demonstrates that the advantages of switching from isopycnic to hybrid coordinates and including more sophisticated turbulence closures outweigh the negative numerical effects of maintaining hybrid vertical coordinates.
NASA Astrophysics Data System (ADS)
Kondratjevs, K.; Zabasta, A.; Selmanovs-Pless, V.
2015-08-01
In the recent years, there has been significant research focus on the safety and reliability of data harvesting and optimal energy consuming by wireless sensor network nodes. If external electrical power fails, the node needs to be able to send notifications to the utility demanding the use of backup energy strategies. The authors of the research offer an approach that can help to use PV panels as an alternative power source for WSN nodes in particular irradiation conditions. Survey and testing of the main types of PV panels offered on the market in conditions closed to real ones, in which WSN nodes are maintained, have been implemented. Based on the test results, maximum power control module parameters can be calculated in order to achieve the best effectiveness of the power control system for a selected type of PV panel or panel group. The novelty of the research is an approach that includes an original test bed design for PV testing, PV testing method and selection of design and MPP control module parameters, which ensure maximum effectiveness of WSN node power feeding. Pēdējos gados vairāki pētījumi ir veltīti problēmām, kas ir saistītas ar enerģijas patēriņa mazināšanu un efektīvu izmantošanu bezvadu sensoru tīklu mezglos. Kad sensors mezgls ir izsmēlis enerģijas krājumu, tas vairs nefunkcionē un atslēdzas no kopēja tīkla, kas var būtiski ietekmēt visa tīkla veiktspēju. Šī pētījuma mērķis ir izveidot barošanas vadības moduli, lai nodrošinātu stabilu elektroapgādes spriegumu autonomi strādājošiem radio signāla atkārtotājiem, sensoriem vai vārtejām, kas darbojas bezvadu sensoru tīklos. Pētījuma ietvaros izstrādāta metode saules paneļu kvalitatīvai salīdzināšanai starp tehnoloģijām vai savā starpā, izvērtējot to atbilstību mērķa pielietojumam. Izstrādātā metode sniedz iespēju veikt kontrolētus testus pie variējošiem, simulētiem gaismas apstākļiem, ļauj prognozēt enerģijas resursus kontekstā ar reģionālajiem apstākļiem un aprēķināt darba režīmus bezvadu tīkla komponentēm vai pieņemt lēmumus par to funkcionalitātes pielāgošanu. Izstrādātais vadības modulis sastāv no saules paneļa fotoelementu moduļa, uzglabāšanas risinājuma (litija vai līdzvērtīgas baterijas) un elektroapgādes pārvaldības moduļa. Pētījuma novitāte ir elektroapgādes pārvaldības modulis, kas nodrošina stabilu un nepārtrauktu elektronisko iekārto darbību dažādos barošanas režīmos, dažādās situācijās, vienlaikus nodrošinot enerģijas saglabāšanu un moduļa sastāvdaļu ilgtspēju. Izstrādātais risinājums nodrošina nepārtrauktu 5V barošanu elektronikas shēmām bez strāvas pārtraukuma, kad notiek komutācija starp barošanas avotiem un enerģijas plūsmām dažādos virzienos. Elektroapgādes pārvaldības modulis nodrošina stabilu spriegumu mainīgos saules radiācijas apstākļos.
NASA Astrophysics Data System (ADS)
Fink, Manfred; Pfannschmidt, Kai; Knevels, Raphel; Fischer, Christian; Brenning, Alexander
2017-04-01
Decisions on measures for adapting to possible climate impacts are critical at both regional and local levels of authority. Currently, the data from EURO-CORDEX is only provided at resolutions (0.11 and 0.44 degrees) that are sufficient for climate analysis in larger scale regions. Therefore, there is a need for more detailed climate information that can assist decision making at the county and town levels. To tackle this challenge, we have developed a tool for the Just Another Modelling System (JAMS; Kralisch et al. 2007) that produces approx. 50 climate characterizing parameters (e.g. average temperature, ice days, climatic water balance, among others) for different time intervals. This tool is combined within the JAMS environment with the J2000g distributed conceptual hydrological model (Krause and Hanisch 2009) to additionally calculate hydro-meteorological parameters, such as actual evapotranspiration, ground water recharge and runoff generation. The resolution of the data was transformed to a higher resolution (250 m) by applying an inverse distance weights (IDW) interpolation. The IDW was combined with an altitude regression approach using digital elevation model data to represent more detailed information of the land surface. We applied this downscaling approach for the federal state of Thuringia, Germany, which is represented by 371206 model units. An ensemble of 10 different EURO-CORDEX models (0.11 degree resolution) in a time period from 1961 to 2100 and measured data from 1960 to 1990 were analyzed. The climate change impacts were estimated by analyzing the changes between historical periods (1960 - 1990) and future periods (2020 - 2050, 2070 -2100) within the modeled EURO-CORDEX ensemble members. We also improved our interpolation approach by replacing IDW with kriging; this approach was especially an advantage for the interpolation of irregularly distributed measurement stations. The results were used to estimate the effects of climate change for the federal state of Thuringia and to support Thuringian climate-change mitigation and adaptation strategies. Future work will concentrate on bias correction of the ensemble members using the measured data. References Kralisch, S., P. Krause, M. Fink, C. Fischer, and W. Flügel (2007): Component based environmental modelling using the JAMS framework, in Proceedings of the MODSIM 2007 International Congress on Modelling and Simulation, edited by D. Kulasiri and L. Oxley, Christchurch, New Zealand Krause P, Hanisch S (2009): Simulation and analysis of the impact of projected climate change on the spatially distributed water balance in Thuringia, Germany. Adv Geosci 21:33-48. doi:10.5194/adgeo-21-33-2009
Aircraft Configuration Noise Reduction. Volume 3. Computer Program Source Listing
1976-06-01
CAT GEN 11 12=1 1+11 CATGtN 32 0360 REAOIKI,10CENIj=4C)(OT(J),.I=11,I2) CATCEN 33 REAO(KI, 100) fDI (JbJ=I#Ii) CATGtkN 34 IF (EOF(KI)) 4C9 20 CATGEN...CORE ANu IURBINE CGNVk 1 COMMON/COREIN/T13,PP3,cMF3,EX3,oELT3,J83, CONVR 13 CONVR 1’ C =5 EXIT FANC .,NVx i COMMUN/FANUAT/NSIG45,NLET45,NAFT45,1CP45,N845
VizieR Online Data Catalog: Luminous of high-z QSOs with SDSS and WISE. II (Yang+, 2016)
NASA Astrophysics Data System (ADS)
Yang, J.; Wang, F.; Wu, X.-B.; Fan, X.; McGreer, I. D.; Bian, F.; Yi, W.; Yang, Q.; Ai, Y.; Dong, X.; Zuo, W.; Green, R.; Jiang, L.; Wang, S.; Wang, R.; Yue, M.
2018-03-01
Our SDSS+WISE selection technique and spectroscopic follow-up observations were discussed in detail in Wang et al. (2016, Cat. J/ApJ/819/24). Our spectroscopic follow-up campaign started in 2013 October with the Lijiang 2.4m telescope (LJT) and Xinglong 2.16m telescope in China, the Kitt Peak 2.3m Bok telescope and 6.5m MMT telescope in the U.S., as well as the 2.3m ANU telescope in Australia. (1 data file).
VizieR Online Data Catalog: SN2009ip UBVRI, UVOT and JHK light curves (Fraser+, 2013)
NASA Astrophysics Data System (ADS)
Fraser, M.; Inserra, C.; Jerkstrand, A.; Kotak, R.; Pignata, G.; Benetti, S.; Botticella, M.-T.; Bufano, F.; Childress, M.; Mattila, S.; Pastorello, A.; Smartt, S. J.; Turatto, M.; Yuan, F.; Anderson, J. P.; Bayliss, D. D. R.; Bauer, F. E.; Chen, T.-W.; Forster Buron, F.; Gal-Yam, A.; Haislip, J. B.; Knapic, C.; Le Guillou, L.; Marchi, S.; Mazzali, P.; Molinaro, M.; Moore, J. P.; Reichart, D.; Smareglia, R.; Smith, K. W.; Sternberg, A.; Sullivan, M.; Takats, K.; Tucker, B. E.; Valenti, S.; Yaron, O.; Young, D. R.; Zhou, G.
2014-11-01
Optical spectroscopic follow-up of SN 2009ip was chiefly obtained with the New Technology Telescope (NTT) + ESO Faint Object Spectrograph and Camera 2 (EFOSC2), as part of the Public European Southern Observatory (ESO) Spectroscopic Survey of Transient Objects (PESSTO). The PESSTO data were supplemented with data from the Telescopio Nazionale Galileo (TNG) + Device Optimized for the LOw RESolution (DOLORES), and the Australian National University (ANU) 2.3m telescope + Wide Field Spectrograph (WiFeS). (3 data files).
1983-01-01
C Z 5 2 2 5110 000 69 HAND TOOLS EDGED NONPOWERED 7 9 3 5 L 06 1 B 4 1 0 100 WAESCHEREI KRAUSE GERMANY 088616 0000 GY I L OJA37 2913 DAJA37-82-00210 B...0 27 WOLFGANG PRAYON GERMANY 090010 0000 GY I D OJA37 0369 DAJA37-82-DO261 B C 2 5 3 2 V212 000 S MOTOR PASSENGER SERVICE 7 9 4 5 L 06 1 B J 1 J 34
1983-01-01
GERMANY 55 55 KOHLEN GRUB GERMANY 9,706 9,706 KOLLER WOLFGANG GERMANY 28 28 KOLLSMANN 0MBN SYSTEM TECHN IK GERMANY 37 37 KONTRO#4 ELEKTRONI C GMBH... KRAUSE GERMANY 56 56 WAGNER GLAS UND GEBAEUDEREINIGUNG GERMANY 374 374 WAGNER GMSM GERMANY 138 136 WAGNER H GERMANY 570 570 WAGNER H a S GARTEN... WOLFGANG PRAYON GERMANY 34 34 WOLLERSHE I M ALFRED GERMANY 47 47 WORMSER AUIOBUSSETRI ED GERMANY 178 178 WUERSCHINGER HANS GERMANY 73 73 WUEST BAU
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beasley, Jonathan
2013-01-01
In this thesis, we explore both total syntheses and methodologies of several aromatic heterocyclic molecules. Extensions of the Kraus indole synthesis toward 2-substituted and 2,3-disubstituted indoles, as well as biologically attractive indolo[2,1-a]isoquinolines are described. Recent renewable efforts directed to commodity maleic acid and the first reported furan-based ionic liquids are described. Our total synthesis of mRNA aptamer ligand PDC-Gly, and its dye coupled forms, plus aminoglycoside dye coupled ligands used in molecular imaging, are described.
The Study of the Interaction between Silica Filler and Silicone Rubber
NASA Astrophysics Data System (ADS)
Liu, Jiesheng; Gong, Xiaoqiang; Zhang, Rongtang
2018-01-01
The interaction between silica filler and silicone rubber was studied by swelling ratio, Kraus curve and crosslinking density test. The results showed that lower values of Vro/Vrf and swelling ratio in modified filler system suggests good filler-matrix interactions. The composites with silane coupling agents show higher crosslink-density compared that of untreated ones. In the light of the above statement, it can be concluded that modification of filler is the crucial factor in creating a good interaction between the filler and silicone rubber.
2013-09-30
and Physiology a-Molecular & Integrative Physiology 161:388-394. Goldstein, T ., I . Mena, S. J. Anthony, R. Medina, P. W. Robinson, D. J. Greig, D. P...behaviour and foraging success in the northern elephant seal. Functional Ecology 27:1055-1063. Lyons, E. T ., T . A. Kuzmina , T . R. Spraker, N. Jaggi...Klanjšček, T ., Lusseau, D., Kraus, S., McMahon, C.R., Robinson, P. W., Schick, R., Schwarz, L.K., Simmons, S. E., Thomas, L., Tyack, P. and Harwood
Quantum Non-thermal Effect from Black Holes Surrounded by Quintessence
NASA Astrophysics Data System (ADS)
Gong, Tian-Xi; Wang, Yong-Jiu
2009-11-01
We present a short and direct derivation of Hawking radiation as a tunneling process across the horizon and compute the tunneling probability. Considering the self-gravitation and energy conservation, we use the Keskiy Vakkuri, Kraus, and Wilczek (KKW) analysis to compute the temperature and entropy of the black holes surrounded by quintessence and obtain the temperature and entropy are different from the Hawking temperature and the Bekenstein-Hawking entropy. The result we get can offer a possible mechanism to deal with the information loss paradox because the spectrum is not purely thermal.
[History of cranial surgery, cerebral tumor surgery and epilepsy surgery in Mexico].
Chico-Ponce de León, F
2009-08-01
The first report of intra-cerebral tumor surgery was provided by Bennett & Goodle, in London, 1884. Worldwide this kind of surgery was performed in France by Chipault, in Italy by Durante, in the United States by Keen and in Deutchland by Krause & Oppenheim. Lavista in Mexico City operated on intra-cerebral tumor in 1891, and the report was printed in 1892. In the same publication, Lavista exhibited the first cases of epilepsy surgery. Since now, it is the first report of this kind of surgery in the Spanish-speaking world.
Zhang, Yequn; Djordjevic, Ivan B; Gao, Xin
2012-08-01
Inspired by recent demonstrations of orbital angular momentum-(OAM)-based single-photon communications, we propose two quantum-channel models: (i) the multidimensional quantum-key distribution model and (ii) the quantum teleportation model. Both models employ operator-sum representation for Kraus operators derived from OAM eigenkets transition probabilities. These models are highly important for future development of quantum-error correction schemes to extend the transmission distance and improve date rates of OAM quantum communications. By using these models, we calculate corresponding quantum-channel capacities in the presence of atmospheric turbulence.
Classification of PSN J13505285-3017097 as an old Type Ia SN with WiFeS
NASA Astrophysics Data System (ADS)
Childress, M.; Scalzo, R.; Tucker, B.; Yuan, F.; Schmidt, B.; Klotz, A.; Conseil, E.
2013-06-01
We report spectroscopic classification of PSN J13505285-3017097 with the Wide Field Spectrograph (WiFeS - Dopita et al., 2007, ApSS, 310, 255) on the ANU 2.3m telescope at Siding Spring Observatory, NSW Australia, using the B3000/R3000 gratings (3500-9800 A, 1 A resolution). PSN J13505285-3017097 was discovered by Conseil on 2013 May 02.22 at mag 18.4 on TAROT images, and photometric follow up shows the light curve peaks in brightness at mag 16 on 2013 May 15.
High Voltage Design Guide for Airborne Equipment
1976-06-01
Capacitance (Capacity). That property of a system of conductors and dielec- trics which permits the storage of electricity when potential dii’ference exists...rjldtlve low prr•strPs ani’d t (.::;•t.rd t LJr e S Pol yI, rene. A thc r:".li1 ti c p!c.,duu.•’d by th [ olyref r i i it on of st yreute (vi nyl Poly i...by cutting continuous filaments, to short lengtn~s. Storage Life. The period nf time during .inich ,liquid re-i: or adi* dye ca3r. be sored anu remain
An Investigation of the Sound Generated by an Axisymmetric Jet Interacting with a Diffuser
1980-09-01
105. 120. J:’REt~U EN C Y, HZ ~OU~U PO~ER ZN’ChNSITY bEVEb,OB TOTA5 POdER ,DB C1/30CTAVK ~ANU) e.,n 209. 74.95 7o.u2 75.72 74.27 75.O7 2bO. 75.78...86.52 86.26 104.53 31500. 79.40 87.33 89.52 87.93 85.46 83.91 82.79 101.88 40000. 76.44 84.35 87.03 85.60 83.32 81.93 81.21 99.43 TOTAL POdER , DB
NASA Astrophysics Data System (ADS)
Henning, Th.; Mancini, L.; Sarkis, P.; Bakos, G. Á.; Hartman, J. D.; Bayliss, D.; Bento, J.; Bhatti, W.; Brahm, R.; Ciceri, S.; Csubry, Z.; de Val-Borro, M.; Espinoza, N.; Fulton, B. J.; Howard, A. W.; Isaacson, H. T.; Jordán, A.; Marcy, G. W.; Penev, K.; Rabus, M.; Suc, V.; Tan, T. G.; Tinney, C. G.; Wright, D. J.; Zhou, G.; Durkan, S.; Lazar, J.; Papp, I.; Sari, P.
2018-02-01
We report the discovery of four close-in transiting exoplanets (HATS-50b through HATS-53b), discovered using the HATSouth three-continent network of homogeneous and automated telescopes. These new exoplanets belong to the class of hot Jupiters and orbit G-type dwarf stars, with brightness in the range V = 12.5–14.0 mag. While HATS-53 has many physical characteristics similar to the Sun, the other three stars appear to be metal-rich ([{Fe}/{{H}}]=0.2{--}0.3), larger, and more massive. Three of the new exoplanets, namely HATS-50b, HATS-51b, and HATS-53b, have low density (HATS-50b: 0.39+/- 0.10 {M}{{J}}, 1.130+/- 0.075 {R}{{J}}; HATS-51b: 0.768+/- 0.045 {M}{{J}}, 1.41+/- 0.19 {R}{{J}}; HATS-53b: 0.595+/- 0.089 {M}{{J}}, 1.340+/- 0.056 {R}{{J}}) and similar orbital periods (3.8297 days, 3.3489 days, 3.8538 days, respectively). Instead, HATS-52b is more dense (mass 2.24+/- 0.15 {M}{{J}} and radius 1.382+/- 0.086 {R}{{J}}) and has a shorter orbital period (1.3667 days). It also receives an intensive radiation from its parent star and, consequently, presents a high equilibrium temperature ({T}{eq}=1834+/- 73 K). HATS-50 shows a marginal additional transit feature consistent with an ultra-short-period hot super Neptune (upper mass limit 0.16 {M}{{J}}), which will be able to be confirmed with TESS photometry. The HATSouth network is operated by a collaboration consisting of Princeton University (PU), the Max Planck Institute für Astronomie (MPIA), the Australian National University (ANU), and the Pontificia Universidad Católica de Chile (PUC). The station at Las Campanas Observatory (LCO) of the Carnegie Institute is operated by PU in conjunction with PUC, the station at the High Energy Spectroscopic Survey (H.E.S.S.) site is operated in conjunction with MPIA, and the station at Siding Spring Observatory (SSO) is operated jointly with ANU. Based in part on observations made with the ESO 3.6 m, the NTT, the MPG 2.2 m and Euler 1.2 m Telescopes at the ESO Observatory in La Silla. Based in part on observations made with the 3.9 m Anglo-Australian Telescope and the ANU 2.3 m Telescope, both at SSO. Based in part on observations made with the Keck I Telescope at Mauna Kea Observatory in Hawaii. Based in part on observations obtained with the facilities of the Las Cumbres Observatory Global Telescope and with the Perth Exoplanet Survey Telescope.
[A contribution to formation of artifacts in the autoradiography (author's transl)].
Gatzke, H D; Jennissen, J J
1976-01-01
KRAUS and GIESE - as proposed by O'CALLAGHAN, STEVENS and WOOD-- could prevent latent image fading throughout exposure with 89Sr/90 Y by addition of 10 mg KBr and 50 g Glucose per liter of water for flotation of stripping films. This method is not useful for the autoradiography of biological material labelled with tritium. Autoradiograms of rat brain slices were investigated after application 3H-leucine, 3H-methionine, 3H-asparagic-acid and 3H-histidine. By adding the above mentioned salts there was an increase of artifacts and a decrease in reproducibility.
Pappas, P W; Leiby, D A
1986-06-01
Four "strains" of Hymenolepis diminuta were examined for morphological variation. These included the ARME "strain" (currently maintained at the University of Keele, U.K.), the OSU "strain" (currently maintained at The Ohio State University) and the TOR (or UT) "strain" (currently maintained at the University of Toronto), all of which were derived from the parental RICE "strain," and the ANU "strain" (currently maintained at the Australian National University). Additionally, 2 separate "clonal" populations (populations derived from single cysticercoids) from both the OSU and ANU "strains" were examined. All "strains" and "clones" were maintained under identical conditions using Tenebrio molitor and male Sprague-Dawley rats as the intermediate and definitive hosts, respectively. The lengths and widths of eggs and larvae (oncospheres) passed in the hosts' feces, and the numbers and distributions of testes in proglottids were quantified and the data analyzed. Although analyses of the lengths and widths of eggs and larvae demonstrated significant differences among some "strains" and "clones," a discriminate analysis of the data indicated these parameters to be of questionable taxonomic significance. The eggs of all "strains" and "clones" consisted of 2 distinct populations differing in density and size but not infectivity; the relative proportions of eggs in the 2 populations were not determined. Considering all possible numbers and distributions of testes, 17 variations were seen in the strobilae of tapeworms. Analyses of the data demonstrated that the "strains" and "clones" could be differentiated clearly using only the frequencies of the 1p2a (1 poral and 2 aporal testes) or 1p3a distribution, or the frequencies of proglottids containing 3 or 4 testes; all other variations failed to clearly differentiate or group the various "strains" and "clones."(ABSTRACT TRUNCATED AT 250 WORDS)
Lee, Jung-Bok; Kim, Hyun Soo; Park, Youngjin
2017-02-01
Chitin synthase (CHS) is an important enzymatic component, which is required for chitin formation in the cuticles and cuticular linings of other tissues in insects. CHSs have been divided into two classes, classes A and B, based on their amino acid sequence similarities and functions. Class A CHS (CHS-A) is specifically expressed in the epidermis and related ectodermal cells such as tracheal cells, while class B CHS (CHS-B) is expressed in gut epithelial cells that produce peritrophic matrices. In this study, we cloned the CHS-A gene from the beet armyworm, Spodoptera exigua (SeCHS-A). The SeCHS-A contains an open reading frame of 4,698 nucleotides, encoding a protein of 1,565 amino acids with a predicted molecular mass of approximately 177.8 kDa. The SeCHS-A mRNA was expressed in all developmental stages and specifically in the epidermis and tracheae tissue by quantitative real-time-PCR analysis. Expression of SeCHS-A gene was suppressed by feeding double-stranded RNA (dsCHS-A, 400 ng/larva) in the third instar larvae of S. exigua. Suppression of the SeCHS-A gene expression significantly increased 35% of mortality on pupation of S. exigua. Also, the third instar larvae fed with dsCHS-A significantly increased susceptibility to entomopathogenic fungi, Beauveria bassiana ANU1 at 3 days after treatment. These results suggest that the SeCHS-A gene plays an important role in development of S. exigua and RNA interference may apply to effective pest control with B. bassiana. © 2017 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Zhang, X.
2017-12-01
Characterisation of an ion source on the Helix MC Plusnoble gas mass spectrometer - pressure dependent mass discrimination Xiaodong Zhang* dong.zhang@anu.edu.au Masahiko Honda Masahiko.honda@anu.edu.au Research School of Earth Sciences, The Australian National University, Canberra, Australia To obtain reliable measurements of noble gas elemental and isotopic abundances in a geological sample it is essential that the mass discrimination (instrument-induced isotope fractionation) of the mass spectrometer remain constant over the working range of noble gas partial pressures. It is known, however, that there are pressure-dependent variations in sensitivity and mass discrimination in conventional noble gas mass spectrometers [1, 2, 3]. In this study, we discuss a practical approach to ensuring that the pressure effect in the Helix MC Plus high resolution, multi-collector noble gas mass spectrometer is minimised. The isotopic composition of atmospheric Ar was measured under a range of operating conditions to test the effects of different parameters on Ar mass discrimination. It was found that the optimised ion source conditions for pressure independent mass discrimination for Ar were different from those for maximised Ar sensitivity. The optimisation can be achieved by mainly adjusting the repeller voltage. It is likely that different ion source settings will be required to minimise pressure-dependent mass discrimination for different noble gases. A recommended procedure for tuning an ion source to reduce pressure dependent mass discrimination will be presented. References: Honda M., et al., Geochim. Cosmochim. Acta, 57, 859 -874, 1993. Burnard P. G., and Farley K. A., Geochemistry Geophysics Geosystems, Volume 1, 2000GC00038, 2000. Mabry J., et al., Journal of Analytical Atomic Spectrometry, 27, 1012 - 1017, 2012.
An assessment of the ICE6G_C(VM5a) glacial isostatic adjustment model
NASA Astrophysics Data System (ADS)
Purcell, A.; Tregoning, P.; Dehecq, A.
2016-05-01
The recent release of the next-generation global ice history model, ICE6G_C(VM5a), is likely to be of interest to a wide range of disciplines including oceanography (sea level studies), space gravity (mass balance studies), glaciology, and, of course, geodynamics (Earth rheology studies). In this paper we make an assessment of some aspects of the ICE6G_C(VM5a) model and show that the published present-day radial uplift rates are too high along the eastern side of the Antarctic Peninsula (by ˜8.6 mm/yr) and beneath the Ross Ice Shelf (by ˜5 mm/yr). Furthermore, the published spherical harmonic coefficients—which are meant to represent the dimensionless present-day changes due to glacial isostatic adjustment (GIA)—contain excessive power for degree ≥90, do not agree with physical expectations and do not represent accurately the ICE6G_C(VM5a) model. We show that the excessive power in the high-degree terms produces erroneous uplift rates when the empirical relationship of Purcell et al. (2011) is applied, but when correct Stokes coefficients are used, the empirical relationship produces excellent agreement with the fully rigorous computation of the radial velocity field, subject to the caveats first noted by Purcell et al. (2011). Using the Australian National University (ANU) groups CALSEA software package, we recompute the present-day GIA signal for the ice thickness history and Earth rheology used by Peltier et al. (2015) and provide dimensionless Stokes coefficients that can be used to correct satellite altimetry observations for GIA over oceans and by the space gravity community to separate GIA and present-day mass balance change signals. We denote the new data sets as ICE6G_ANU.
Multidisciplinary studies of the dust storm that affected Sydney in September 2009
NASA Astrophysics Data System (ADS)
De Deckker, P.
2012-04-01
A major dust storm transgressed over southeastern Australia in September 2009 and continued as far as northern Queensland [to the north], New Zealand and New Caledonia [to the east] . We analysed samples of the dust for organic compounds, its microbiological composition, pollen, trace and rare earth elements as well as Sr and Nd isotopes. Grain size analysis was also performed on some of the samples. We also obtained information on the meteorological conditions that led to the large dust plume and its pathway. Our geochemical fingerprinting allowed us to determine the origin of the dust, and this was confirmed by meteorological observations and satellite imagery. As the pathway of the dust plume went over the city of Canberra, located to the southwest of Sydney, we were able to collect samples of dust that fell with rain, and the surprise was that the geochemical composition of the dust varied with time [and dust fall], identifying that as the dust plume transgressed over the landscape, it picked up additional material that was compositionally different from its point of origin. We also compared our data with those obtained from another major dust event that affected Canberra in October 2002, and a number of important differences are noted, particularly with respect of the microbiological composition of the dust, and its chemical composition. Collaborators on this project are: Chris Munday and Gwen Allison [microbiology]: Research School of Biology, ANU; Jochen Brocks and Janet Hope [organic chemistry] and Marc Norman [inorganic geochemistry]: Research School of Earth Sciences, ANU; Tadhg O'Loingsigh and Nigel Tapper [meteorology, satellite imagery] and Sander van der Kaars [palynology]: Geography and Environmental Science, Monash University; and J.-B. Stuut [grain size analysis], NIOZ.
PSN J11290437+1714095 is a Type Ia supernova (91T-like) near maximum light
NASA Astrophysics Data System (ADS)
Childress, M.; Owen, C.; Scalzo, R.; Yuan, F.; Schmidt, B.; Tucker, B.
2013-12-01
We report spectroscopic classification of PSN J11290437+1714095 with the Wide Field Spectrograph (WiFeS - Dopita et al., 2007, ApSS, 310, 255) on the ANU 2.3m telescope at Siding Spring Observatory, NSW Australia, using the B3000/R3000 gratings (3500-9800 A, 1 A resolution). PSN J11290437+1714095 was discovered by TAROT on 2013 Dec 11.09 at mag 15.9 in UGC 6483. A 20 minute spectrum of the SN on 2013 Dec 12.72 shows this to be a Type Ia supernova of the SN 1991T subclass near maximum light.
Seismology at the Australian National University; an interview with Anton L. Hales
Spall, H.
1980-01-01
Dr. Anton L. Hales is a leading seismologist who has just retired as Director of the Research School of Earth Sciences at the Australian National University (ANU), Canberra. Prior to that, he headed the Geosciences Division at the University of Texas at Dallas, and, before that, he was Director of the Bernard Price Institute of Geophysical Research at the University of the Witwatersrand Johannesburg, South Africa. he is about to step down as President of the International Geodynamics Commission. Dr. Hales' research has involved marine geophysics, the travel times of seismic waves, and the structure of the Earth's crust and upper mantle.
Obituary: John Daniel Kraus, 1910-2004
NASA Astrophysics Data System (ADS)
Kraus, John D., Jr.; Marhefka, Ronald J.
2005-12-01
John Daniel Kraus, 94, of Delaware, Ohio, director of the Ohio State University "Big Ear" Radio Observatory, physicist, inventor, and environmentalist died 18 July 2004 at his home in Delaware, Ohio. He was born on 28 June 1910 in Ann Arbor, Michigan. He received a Bachelor of Science in 1930, a Master of Science in 1931, and a PhD in physics in 1933 (at 23 years of age), all from the University of Michigan, Ann Arbor. During the 1930s at Michigan, he was involved in physics projects, antenna consulting, and in atomic-particle-accelerator research using the University of Michigan's premier cyclotron. Throughout the late 1920s and the 1930s, John was an avid radio amateur with call sign W8JK. He was back on the air in the 1970s. In 2001 the amateur radio magazine CQ named him to the inaugural class of its Amateur Radio Hall of Fame. He developed many widely used innovative antennas. The "8JK closely spaced array" and the "corner reflector" were among his early designs. Edwin H. Armstrong wrote John in July 1941 indicating in part, "I have read with interest your article in the Proceedings of the Institute on the corner reflector...Please let me congratulate you on a very fine piece of work." Perhaps John's most famous invention, and a product of his intuitive reasoning process, is the helical antenna, widely used in space communications, on global positioning satellites, and for other applications. During World War II, John was in Washington, DC as a civilian scientist with the U.S. Navy responsible for "degaussing" the electromagnetic fields of steel ships to make them safe from magnetic mines. He also worked on radar countermeasures at Harvard University's Radio Research Laboratory. He received the U.S. Navy Meritorious Civilian Service Award for his war work. In 1946 he took a faculty position at Ohio State University, becoming professor in 1949, and retiring in 1980 as McDougal Professor Emeritus of Electrical Engineering and Astronomy. Even so, he never retired. He was always working, researching, writing, and seeking new knowledge. He was active and vital to the end. Early on, John became fascinated by Karl Jansky's discoveries of radio noise from space and the potential to use radio waves rather than visible light to "see" the universe. He maintained contact with radio astronomy pioneer, Grote Reber. John pursued radio-astronomy research in parallel with textbook writing and his OSU teaching responsibilities. By 1953 he was observing with a 96 helix antenna and had produced one of the first maps of the radio sky. This was followed by his design and construction of the innovative, 110-meter, "Big Ear" Radio Telescope - a tiltable, flat reflector joined to a fixed, standing, paraboloidal reflector. Observations began in the mid-1960s. Interspersed with this work were radio observations of Jupiter, Mars, and Venus as well as of the ionized trails of the Sputniks and U.S. satellites. John and his radio astronomy team discovered some of the most distant known objects at the edge of the universe and produced one of the most complete surveys of the radio sky. As he stated, "The radio sky is no carbon copy of the visible; it is a new and different firmament." He was closely identified with efforts and activities related to the Search for Extraterrestrial Intelligence or SETI. He edited and published the first magazine on the subject called Cosmic Search. The now famous "WOW!" signal, of possible extraterrestrial origin, was detected by "Big Ear" in 1977. He was the author of hundreds of technical articles and the holder of many patents. John was a dedicated educator and inspiring teacher, renown for providing plain English solutions to complicated problems. He was thesis advisor to 58 PhD and Master's candidates. His textbooks made complex subjects accessible to many readers. They have been widely used throughout the world and include "Antennas" (McGraw-Hill: 1950, 1988, 2002) and "Electromagnetics" (McGraw-Hill: 1953, 1973, 1984, 1992, 1999) and "Radio Astronomy" (McGraw-Hill: 1966; Cygnus-Quasar: 1986). They have appeared in Chinese, Japanese, Korean, Spanish, Russian, and Portuguese. He also wrote popular books, including the autobiographical "Big Ear" and "Big Ear Two" (Cygnus-Quasar: 1976, 1995), and the instructional "Our Cosmic Universe" (Cygnus-Quasar: 1980). His professional memberships included the American Astronomical Society, election to the National Academy of Engineering (1972), and Fellow of the Institute of Electrical and Electronic Engineers. He received the Centennial Medal (1984), the Edison Medal (1985), and the Heinrich Hertz Medal (1990) from the IEEE. The Antenna and Propagation Society of IEEE twice awarded him its Distinguished Achievement Award, the last in 2003. He was awarded the Sullivant Medal (1970) from the Ohio State University and the Outstanding Achievement Award (1981) from the University of Michigan. John and his wife, Alice Nelson Kraus, whom he married in 1941, were committed environmentalists. Alice and he donated the 80-acre Kraus Wilderness Preserve to the Ohio Wesleyan University in 1976. They also endowed scholarships to enhance environmental learning for students at Ohio Wesleyan and OSU. In addition, John was a passionate advocate of metrification in the USA. Predeceased in 2002 by his beloved wife, he is survived by two sons, John D. Kraus, Jr., and Nelson H. Kraus, and five grandchildren. His professional and personal papers are housed at the National Radio Astronomy Observatory archives in Charlottesville, Virginia. John was viewed by many as a last living link to many of the astonishing scientific discoveries of the 20th century. He valued an open mind and direct physical insights and was of a by-gone era of hands-on invention, empirical testing, and observational research. Yet, he commanded an insightful grasp of the theory, which he could translate into thought provoking learning experiences for students and working engineers alike. In his epilogue to "Big Ear", John said, "I haven't discovered the ultimate truths of the universe but I have experienced the thrill and excitement of playing a small part in the adventure of exploring the astounding, baffling, stranger-than-fiction cosmos in which we dwell."
Quantum Fisher information of the Greenberg-Horne-Zeilinger state in decoherence channels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma Jian; Huang Yixiao; Wang Xiaoguang
2011-08-15
Quantum Fisher information of a parameter characterizes the sensitivity of the state with respect to changes of the parameter. In this article, we study the quantum Fisher information of a state with respect to SU(2) rotations under three decoherence channels: the amplitude-damping, phase-damping, and depolarizing channels. The initial state is chosen to be a Greenberg-Horne-Zeilinger state of which the phase sensitivity can achieve the Heisenberg limit. By using the Kraus operator representation, the quantum Fisher information is obtained analytically. We observe the decay and sudden change of the quantum Fisher information in all three channels.
Fractional discrete-time consensus models for single- and double-summator dynamics
NASA Astrophysics Data System (ADS)
Wyrwas, Małgorzata; Mozyrska, Dorota; Girejko, Ewa
2018-04-01
The leader-following consensus problem of fractional-order multi-agent discrete-time systems is considered. In the systems, interactions between opinions are defined like in Krause and Cucker-Smale models but the memory is included by taking the fractional-order discrete-time operator on the left-hand side of the nonlinear systems. In this paper, we investigate fractional-order models of opinions for the single- and double-summator dynamics of discrete-time by analytical methods as well as by computer simulations. The necessary and sufficient conditions for the leader-following consensus are formulated by proposing a consensus control law for tracking the virtual leader.
PSN J02455988-0734270 in NGC 1084 is a young type II-P SN
NASA Astrophysics Data System (ADS)
Childress, M.; Scalzo, R.; Yuan, F.; Schmidt, B.
2012-08-01
We report the spectroscopic classification of the optical transient PSN J02455988-0734270 in NGC 1084 (disc. 2012-08-11.039 by B. Monard) based on an optical spectrum taken with the Wide Field Spectrograph (WiFeS - Dopita et al., 2007, ApSS, 310, 255) on the ANU 2.3m telescope at Siding Spring Observatory, NSW Australia, using the B3000/R3000 gratings (3600-10000, 1A resolution). The transient spectrum was compared to supernova spectral templates using SNID (Blondin & Tonry, 2007, ApJ, 666, 1024) indicating it to be a supernova of type II-P at a very young age, perhaps only a few days after explosion.
NASA Astrophysics Data System (ADS)
Kraus, D.; Hartley, N. J.; Frydrych, S.; Schuster, A. K.; Rohatsch, K.; Rödel, M.; Cowan, T. E.; Brown, S.; Cunningham, E.; van Driel, T.; Fletcher, L. B.; Galtier, E.; Gamboa, E. J.; Laso Garcia, A.; Gericke, D. O.; Granados, E.; Heimann, P. A.; Lee, H. J.; MacDonald, M. J.; MacKinnon, A. J.; McBride, E. E.; Nam, I.; Neumayer, P.; Pak, A.; Pelka, A.; Prencipe, I.; Ravasio, A.; Redmer, R.; Saunders, A. M.; Schölmerich, M.; Schörner, M.; Sun, P.; Turner, S. J.; Zettl, A.; Falcone, R. W.; Glenzer, S. H.; Döppner, T.; Vorberger, J.
2018-05-01
Diamond formation in polystyrene (C8H8)n, which is laser-compressed and heated to conditions around 150 GPa and 5000 K, has recently been demonstrated in the laboratory [Kraus et al., Nat. Astron. 1, 606-611 (2017)]. Here, we show an extended analysis and comparison to first-principles simulations of the acquired data and their implications for planetary physics and inertial confinement fusion. Moreover, we discuss the advanced diagnostic capabilities of adding high-quality small angle X-ray scattering and spectrally resolved X-ray scattering to the platform, which shows great prospects of precisely studying the kinetics of chemical reactions in dense plasma environments at pressures exceeding 100 GPa.
NASA Astrophysics Data System (ADS)
Brahm, R.; Hartman, J. D.; Jordán, A.; Bakos, G. Á.; Espinoza, N.; Rabus, M.; Bhatti, W.; Penev, K.; Sarkis, P.; Suc, V.; Csubry, Z.; Bayliss, D.; Bento, J.; Zhou, G.; Mancini, L.; Henning, T.; Ciceri, S.; de Val-Borro, M.; Shectman, S.; Crane, J. D.; Arriagada, P.; Butler, P.; Teske, J.; Thompson, I.; Osip, D.; Díaz, M.; Schmidt, B.; Lázár, J.; Papp, I.; Sári, P.
2018-03-01
We report the discovery of four short-period extrasolar planets transiting moderately bright stars from photometric measurements of the HATSouth network coupled to additional spectroscopic and photometric follow-up observations. While the planet masses range from 0.26 to 0.90 {M}{{J}}, the radii are all approximately a Jupiter radii, resulting in a wide range of bulk densities. The orbital period of the planets ranges from 2.7 days to 4.7 days, with HATS-43b having an orbit that appears to be marginally non-circular (e = 0.173 ± 0.089). HATS-44 is notable for having a high metallicity ([{Fe}/{{H}}] = 0.320 ± 0.071). The host stars spectral types range from late F to early K, and all of them are moderately bright (13.3 < V < 14.4), allowing the execution of future detailed follow-up observations. HATS-43b and HATS-46b, with expected transmission signals of 2350 ppm and 1500 ppm, respectively, are particularly well suited targets for atmospheric characterization via transmission spectroscopy. The HATSouth network is operated by a collaboration consisting of Princeton University (PU), the Max Planck Institute für Astronomie (MPIA), the Australian National University (ANU), and the Pontificia Universidad Católica de Chile (PUC). The station at Las Campanas Observatory (LCO) of the Carnegie Institute is operated by PU in conjunction with PUC, the station at the High Energy Spectroscopic Survey (H.E.S.S.) site is operated in conjunction with MPIA, and the station at Siding Spring Observatory (SSO) is operated jointly with ANU. This paper includes data gathered with the MPG 2.2 m and ESO 3.6 m telescopes at the ESO Observatory in La Silla. This paper includes data gathered with the 6.5 meter Magellan Telescopes located at Las Campanas Observatory, Chile.
It Takes A 'Village of Partnerships' To Raise A 'Big Data Facility' In A 'Big Data World'.
NASA Astrophysics Data System (ADS)
Evans, B. J. K.; Wyborn, L. A.
2015-12-01
The National Computational Infrastructure (NCI) at the Australian National University (ANU) has collocated a priority set of national and international data assets that span a wide range of domains from climate, oceans, geophysics, environment, astronomy, bioinformatics and the social sciences. The data are located on a 10 PB High Performance Data (HPD) Node that is integrated with a High Performance Computing (HPC) facility to enable a new style of Data-intensive in-situ analysis. Investigators can either log in via direct access to the data collections: access is also provided via modern standards-based web services. The NCI integrated HPD/HPC facility is supported by a 'village' of partnerships. NCI itself operates as a formal partnership between the ANU and three major National Scientific Agencies: CSIRO, the Bureau of Meteorology (BoM) and Geoscience Australia (GA). These same agencies are also the custodians of many of the national data collections hosted at NCI, and in partnership with other collaborating national and overseas organisations have agreed to work together to develop a shared data environment and use standards that enable interoperability between the collections, rather than isolating their collections as separate entities that each agency runs independently. To effectively analyse these complex and large volume data sets, NCI has entered into a series of national and national partnerships with international agencies to provide world-class digital analytical environments that allow computational to be conducted and shared. The ability for government and research to work in partnership at the NCI has been well established over the last decade, mainly with BoM, CSIRO, and GA. New emerging industry linkages are now being encouraged by revised government agendas and these promises to foster a new series of partnerships that will increase uptake of this major government funded infrastructure and promise to foster further collaboration and innovation.
HATS-1b: The First Transiting Planet Discovered by the HATSouth Survey
NASA Astrophysics Data System (ADS)
Penev, K.; Bakos, G. Á.; Bayliss, D.; Jordán, A.; Mohler, M.; Zhou, G.; Suc, V.; Rabus, M.; Hartman, J. D.; Mancini, L.; Béky, B.; Csubry, Z.; Buchhave, L.; Henning, T.; Nikolov, N.; Csák, B.; Brahm, R.; Espinoza, N.; Conroy, P.; Noyes, R. W.; Sasselov, D. D.; Schmidt, B.; Wright, D. J.; Tinney, C. G.; Addison, B. C.; Lázár, J.; Papp, I.; Sári, P.
2013-01-01
We report the discovery of HATS-1b, a transiting extrasolar planet orbiting the moderately bright V = 12.05 G dwarf star GSC 6652-00186, and the first planet discovered by HATSouth, a global network of autonomous wide-field telescopes. HATS-1b has a period of P ≈ 3.4465 days, mass of Mp ≈ 1.86 M J, and radius of Rp ≈ 1.30 R J. The host star has a mass of 0.99 M ⊙ and radius of 1.04 R ⊙. The discovery light curve of HATS-1b has near-continuous coverage over several multi-day timespans, demonstrating the power of using a global network of telescopes to discover transiting planets. The HATSouth network is operated by a collaboration consisting of Princeton University (PU), the Max Planck Institute für Astronomie (MPIA), and the Australian National University (ANU). The station at Las Campanas Observatory (LCO) of the Carnegie Institute, is operated by PU in conjunction with collaborators at the Pontificia Universidad Católica de Chile (PUC), the station at the High Energy Spectroscopic Survey (HESS) site is operated in conjunction with MPIA, and the station at Siding Spring Observatory (SSO) is operated jointly with ANU. Based in part on observations made with the Nordic Optical Telescope, operated on the island of La Palma in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. Based on observations made with the MPG/ESO 2.2 m Telescope at the ESO Observatory in La Silla. FEROS ID programmes: P087.A-9014(A), P088.A-9008(A), P089.A-9008(A), P087.C-0508(A). GROND ID programme: 089.A-9006(A). This paper uses observations obtained with facilities of the Las Cumbres Observatory Global Telescope.
Iceless Icy Moons: Is the Nice Model In Trouble?
NASA Astrophysics Data System (ADS)
Dones, Henry C. Luke; Levison, H. F.
2012-05-01
Nimmo and Korycansky (2012; henceforth NK12) stated that if the outer Solar System underwent a Late Heavy Bombardment (LHB) in the Nice model, the mass striking the icy satellites at speeds up to tens of km/s would have vaporized so much ice that moons such as Mimas, Enceladus, and Miranda would have been devolatilized. NK12's possible explanations of this apparent discrepancy with observations include (1) the mass influx was a factor of 10 less than that in the Nice model; (2) the mass distribution of the impactors was top-heavy, so that luck might have saved some of the moons from suffering large, vapor-removing impacts; or (3) the inner moons formed after the LHB. NK12 calculated the mass influx onto the satellites from the lunar impact rate estimated by Gomes et al. (2005) and scaling factors calculated by Zahnle et al. (1998, 2003; also see Barr and Canup 2010). Production of vapor in hypervelocity impacts is calculated from Kraus et al. (2011). Our preliminary results show that there is about an order-of-magnitude uncertainty in the mass striking the satellites during the LHB, with NK12's estimate at the upper end of the range. We will discuss how the mass influx depends on the velocity and mass distributions of the impactors. The Nice model lives. We thank the NASA Lunar Science Institute (http://lunarscience.nasa.gov/) for support. Barr, A.C., Canup, R.M., Nature Geoscience 3, 164-167 (2010). Gomes, R., Levison, H.F., Tsiganis, K., Morbidelli, A., Nature 435, 466-469 (2005). Kraus, R.G., Senft, L.E., Stewart, S.T., Icarus 214, 724-738 (2011). Nimmo, F., Korycansky, D.G., Icarus, in press, http://www.sciencedirect.com/science/article/pii/S0019103512000310 (2012). Zahnle, K., Dones, L., Levison, H.F., Icarus 136, 202-222 (1998). Zahnle, K., Schenk, P., Levison, H.F., Dones, L., Icarus 163, 263-289 (2003).
Development of Flight-Safety Prediction Methodology for U.S. Naval Safety Center
1969-06-01
i~.n~. I ShS81.ib A m, fOP i WY ii W i i A (G Wr aft sod Nabe ~reaeded by n or 6n/ai*rgtan e e *SN ONIa "N I a)M ) ) ()Function or Equipment Name...110.1 PE99. SYSTfM D1.60ANU Y 1ET 4333 Chet A 4 0 BILOWS IIL A.134 11 VEIL SY STE BlNCS 14314 121k A OVISC0$J6 OAMPIMS Cho tic 013121230 SUNS viscous...02113 PN64*0 SPOILER P841 CYL 14212 KEA6 OUTBYOARD SPOILER PWR CYL 14252 *CC@& SPOILER FOLLOW Up Roo A1S 1425 RI ~ A FOLLOW UP TORfiJ tUsk Sy 1421. CSI5
1990-03-01
rare in Missouri. The record is from 1987. Red berried elder ( Sambucus pubens) occurs within 1.0 miles of the project area. This plant is endangered...hIALLARD IYPIACTS AAHU’x r U rr PLAN Figure 1- Plan Comparisons A-19 Note that Plan C (sediment deflection) would provide essentially no benefits to...S TA.T$ OIL UTAILS jfy 9.LE.CTtICA.l. 0 BasMW6 WORN Mfaiss wo1nu SYSTEM ,mW30mmoRALummAnuGiWEN PinOain =1~ POOL sIKIrval wLI $11 t PLATE I 44 D ~SAY8
150 kW Class Solar Electric Propulsion Spacecraft Power Architecture Model
NASA Technical Reports Server (NTRS)
Csank, Jeffrey T.; Aulisio, Michael V.; Loop, Benjamin
2017-01-01
The National Aeronautics and Space Administration (NASA) Solar Electric Propulsion Technology Demonstration Mission in conjunction with PC Krause and Associates has created a Simulink-based power architecture model for a 50 kilo-Watt (kW) solar electric propulsion system. NASA has extended this model to investigate 150 kW solar electric propulsion systems. Increasing the power system capability from 50 kW to 150 kW better aligns with the anticipated power requirements for Mars and other deep space explorations. The high-power solar electric propulsion capability has been identified as a critical part of NASAs future beyond-low-Earth-orbit for human-crewed exploration missions. This paper presents multiple 150 kW architectures, simulation results, and a discussion of their merits.
Charged structure constants from modularity
NASA Astrophysics Data System (ADS)
Das, Diptarka; Datta, Shouvik; Pal, Sridip
2017-11-01
We derive a universal formula for the average heavy-heavy-light structure constants for 2 d CFTs with non-vanishing u(1) charge. The derivation utilizes the modular properties of one-point functions on the torus. Refinements in N=2 SCFTs, show that the resulting Cardy-like formula for the structure constants has precisely the same shifts in the central charge as that of the thermodynamic entropy found earlier. This analysis generalizes the recent results by Kraus and Maloney for CFTs with an additional global u(1) symmetry [1]. Our results at large central charge are also shown to match with computations from the holographic dual, which suggest that the averaged CFT three-point coefficient also serves as a useful probe of detecting black hole hair.
Towards the SQL: Status of the direct thermal-noise measurements at the ANU
NASA Astrophysics Data System (ADS)
Mow-Lowry, C. M.; Goßler, S.; Slagmolen, B. J. J.; Cumpston, J.; Gray, M. B.; McClelland, D. E.
2006-03-01
We present the preliminary results for an experiment that aims to perform direct measurements of suspension thermal noise. The experiment is based on a niobium flexure membrane approximately 200 µm thickness that is operated as a stable inverted pendulum. A 0.25 g mirror suspended by this flexure membrane is used as the end mirror of a Fabry-Perot test cavity. This test cavity has a length of 12mm and a finesse of about 800. It is mounted at the lowest stage of a quadruple cascaded pendulum suspension, enclosed in a high-vacuum envelope. The length of test cavity is stabilized with 1Hz bandwidth to a Nd:YAG laser, which itself is stabilized with high bandwidth to the length of a suspended Zerodur reference cavity of finesse 6000.
Quantum Consciousness - The Road to Reality
NASA Astrophysics Data System (ADS)
Goradia, Shantilal
Per Einstein's theory mass tells space how to curve and space tells mass how to move. How do they tell\\x9D? The question boils down to information created by quantum particles blinking ON and OFF analogous to 'Ying and Yang' or some more complex ways that may include dark matter. Consciousness, dark matter, quantum physics, uncertainty principle, constants of nature like strong coupling, fine structure constant, cosmological constant introduced by Einstein, information, gravitation etc. are fundamentally consequences of that ONE TOE. Vedic philosophers, who impressed Schrodinger so much, called it ATMA split in the categories of AnuAtma (particle soul), JivAtma (life soul) and ParamAtma (Omnipresent soul) which we relate to quantum physics, biology and cosmology. There is no separate TOE (Theory of Everything) for any one thing.
NASA Astrophysics Data System (ADS)
Gajek, Z.
2004-05-01
The electronic properties of the actinide ions in the series of semi-conducting, antiferromagnetic compounds: dioxides, AnO2 and oxychalcogenides, AnOY, where An=U, Np and Y=S, Se, are re-examined from the point of view of the consistency of the crystal field (CF) model. The discussion is based on the supposition that the effective metal-ligand interaction solely determines the net CF effect in non-metallic compounds. The main question we address here is, whether a reliable, consistent description of the CF effect in terms of the intrinsic parameters can be achieved for this particular family of compounds. Encouraging calculations reported previously for the AnO2 and UOY series serve as a reference data in the present estimation of electronic structure parameters for neptunium oxychalcogenides.
Avalanche photo diodes in the observatory environment: lucky imaging at 1-2.5 microns
NASA Astrophysics Data System (ADS)
Vaccarella, A.; Sharp, R.; Ellis, M.; Singh, S.; Bloxham, G.; Bouchez, A.; Conan, R.; Boz, R.; Bundy, D.; Davies, J.; Espeland, B.; Hart, J.; Herrald, N.; Ireland, M.; Jacoby, G.; Nielsen, J.; Vest, C.; Young, P.; Fordham, B.; Zovaro, A.
2016-08-01
The recent availability of large format near-infrared detectors with sub-election readout noise is revolutionizing our approach to wavefront sensing for adaptive optics. However, as with all near-infrared detector technologies, challenges exist in moving from the comfort of the laboratory test-bench into the harsh reality of the observatory environment. As part of the broader adaptive optics program for the GMT, we are developing a near-infrared Lucky Imaging camera for operational deployment at the ANU 2.3 m telescope at Siding Spring Observatory. The system provides an ideal test-bed for the rapidly evolving Selex/SAPHIRA eAPD technology while providing scientific imaging at angular resolution rivalling the Hubble Space Telescope at wavelengths λ = 1.3-2.5 μm.
Wear Calculation for Sliding Friction Pairs
NASA Astrophysics Data System (ADS)
Springis, G.; Rudzitis, J.; Avisane, A.; Leitans, A.
2014-04-01
One of the principal objectives of modern production process is the improvement of quality level; this means also guaranteeing the required service life of different products and increase in their wear resistance. To perform this task, prediction of service life of fitted components is of crucial value, since with the development of production technologies and measuring devices it is possible to determine with ever increasing precision the data to be used also in analytical calculations. Having studied the prediction theories of wear process that have been developed in the course of time and can be classified into definite groups one can state that each of them has shortcomings that might strongly impair the results thus making unnecessary theoretical calculations. The proposed model for wear calculation is based on the application of theories from several branches of science to the description of 3D surface micro-topography, assessing the material's physical and mechanical characteristics, substantiating the regularities in creation of the material particles separated during the wear process and taking into consideration definite service conditions of fittings. ums Mūsdienu ražošanas procesa viens no pamatmērķiem ir produkcijas kvalitātes līmeņa paaugstināšana, tas nozīmē arī dažādu izstrādājumu nepieciešamā kalpošanas laika nodrošināšanu un nodilumizturības palielināšanu. Svarīga loma šī uzdevuma sasniegšanā ir salāgojamo detaļu kalpošanas laika prognozēšanai, kas ir ļoti aktuāls jautājums, jo attīstoties dažādām ražošanas, kā arī mēriekārtu tehnoloģijām, kļūst iespējams arvien precīzāk noteikt nepieciešamos datus, kuri vēlāk tiek izmantoti arī analītiskajos aprēķinos. Apskatot laika gaitā izstrādātās dilšanas procesa prognozēšanas teorijas, kuras var klasificēt, apkopojot tās noteiktās grupās, ņemot par pamatu līdzīgas teorētiskās pieejas, jāsaka, ka katrai no tām piemīt dažādi trūkumi, kuri var ietekmēt rezultātu precizitāti, neievērtējot svarīgus pamatparametrus, kā arī radīt nepieciešamību pēc nelietderīgiem papildus praktiskajiem eksperimentiem, kā rezultātā zūd nepieciešamība pēc teorētiskā aprēķina. Piedāvātais dilšanas procesa aprēķinu modelis ir balstīts uz vairāku zinātnes nozaru teoriju pielietošanu, piemērojot šīs teorijas 3D virsmas mikrotopogrāfijas aprakstā, ievērtējot materiāla fizikāli-mehāniskos raksturlielumus, pamatojot dilšanas procesā radušos atdalīto materiāla daļiņu rašanās likumsakarības un ņemot vērā konkrētus salāgojuma ekspluatācijas apstākļus.
150 kW Class Solar Electric Propulsion Spacecraft Power Architecture Model
NASA Technical Reports Server (NTRS)
Csank, Jeffrey T.; Aulisio, Michael V.; Loop, Benjamin
2017-01-01
The National Aeronautics and Space Administration (NASA) Solar Electric Propulsion Technology Demonstration Mission (SEP TDM), in conjunction with PC Krause and Associates, has created a Simulink-based power architecture model for a 50 kilo-Watt (kW) solar electric propulsion system. NASA has extended this model to investigate 150 kW solar electric propulsion systems. Increasing the power capability to 150 kW is an intermediate step to the anticipated power requirements for Mars and other deep space applications. The high-power solar electric propulsion capability has been identified as a critical part of NASA’s future beyond-low-Earth-orbit for human-crewed exploration missions. This paper presents four versions of a 150 kW architecture, simulation results, and a discussion of their merits.
The salinity effect in a mixed layer ocean model
NASA Technical Reports Server (NTRS)
Miller, J. R.
1976-01-01
A model of the thermally mixed layer in the upper ocean as developed by Kraus and Turner and extended by Denman is further extended to investigate the effects of salinity. In the tropical and subtropical Atlantic Ocean rapid increases in salinity occur at the bottom of a uniformly mixed surface layer. The most significant effects produced by the inclusion of salinity are the reduction of the deepening rate and the corresponding change in the heating characteristics of the mixed layer. If the net surface heating is positive, but small, salinity effects must be included to determine whether the mixed layer temperature will increase or decrease. Precipitation over tropical oceans leads to the development of a shallow stable layer accompanied by a decrease in the temperature and salinity at the sea surface.
Damage spreading and opinion dynamics on scale-free networks
NASA Astrophysics Data System (ADS)
Fortunato, Santo
2005-03-01
We study damage spreading among the opinions of a system of agents, subjected to the dynamics of the Krause-Hegselmann consensus model. The damage consists in a sharp change of the opinion of one or more agents in the initial random opinion configuration, supposedly due to some external factors and/or events. This may help to understand for instance under which conditions special shocking events or targeted propaganda are able to influence the results of elections. For agents lying on the nodes of a Barabási-Albert network, there is a damage spreading transition at a low value εd of the confidence bound parameter. Interestingly, we find as well that there is some critical value εs above which the initial perturbation manages to propagate to all other agents.
Evolution of the squeezing-enhanced vacuum state in the amplitude dissipative channel
NASA Astrophysics Data System (ADS)
Ren, Gang; Du, Jian-ming; Zhang, Wen-hai
2018-05-01
We study the evolution of the squeezing-enhanced vacuum state (SEVS) in the amplitude dissipative channel by using the two-mode entangled state in the Fock space and Kraus operator. The explicit formulation of the output state is also given. It is found that the output state does not exhibit sub-Poissonian behavior for the nonnegative value of the Mandel's Q-parameters in a wide range of values of squeezing parameter and dissipation factor. It is interesting to see that second-order correlation function is independent of the dissipation factor. However, the photon-number distribution of the output quantum state shows remarkable oscillations with respect to the dissipation factor. The shape of Wigner function and the degree of squeezing show that the initial SEVS is dissipated by the amplitude dissipative channel.
HATS-17b: A Transiting Compact Warm Jupiter in a 16.3 Day Circular Orbit
NASA Astrophysics Data System (ADS)
Brahm, R.; Jordán, A.; Bakos, G. Á.; Penev, K.; Espinoza, N.; Rabus, M.; Hartman, J. D.; Bayliss, D.; Ciceri, S.; Zhou, G.; Mancini, L.; Tan, T. G.; de Val-Borro, M.; Bhatti, W.; Csubry, Z.; Bento, J.; Henning, T.; Schmidt, B.; Rojas, F.; Suc, V.; Lázár, J.; Papp, I.; Sári, P.
2016-04-01
We report the discovery of HATS-17b, the first transiting warm Jupiter of the HATSouth network. HATS-17b transits its bright (V = 12.4) G-type ({M}\\star = 1.131+/- 0.030 {M}⊙ , {R}\\star = {1.091}-0.046+0.070 {R}⊙ ) metal-rich ([Fe/H] = +0.3 dex) host star in a circular orbit with a period of P = 16.2546 days. HATS-17b has a very compact radius of 0.777+/- 0.056 {R}{{J}} given its Jupiter-like mass of 1.338+/- 0.065 {M}{{J}}. Up to 50% of the mass of HATS-17b may be composed of heavy elements in order to explain its high density with current models of planetary structure. HATS-17b is the longest period transiting planet discovered to date by a ground-based photometric survey, and is one of the brightest transiting warm Jupiter systems known. The brightness of HATS-17 will allow detailed follow-up observations to characterize the orbital geometry of the system and the atmosphere of the planet. The HATSouth network is operated by a collaboration consisting of Princeton University (PU), the Max Planck Institute für Astronomie (MPIA), the Australian National University (ANU), and the Pontificia Universidad Católica de Chile (PUC). The station at Las Campanas Observatory (LCO) of the Carnegie Institute is operated by PU in conjunction with PUC, the station at the High Energy Spectroscopic Survey (H.E.S.S.) site is operated in conjunction with MPIA, and the station at Siding Spring Observatory (SSO) is operated jointly with ANU. This paper includes data gathered with the MPG 2.2 m telescope at the ESO Observatory in La Silla and with the 3.9 m AAT in Siding Spring Observatory. This paper uses observations obtained with facilities of the Las Cumbres Observatory Global Telescope. Based on observations taken with the HARPS spectrograph (ESO 3.6 m telescope at La Silla) under programme 097.C-0571.
HATS-31b through HATS-35b: Five Transiting Hot Jupiters Discovered By the HATSouth Survey
NASA Astrophysics Data System (ADS)
de Val-Borro, M.; Bakos, G. Á.; Brahm, R.; Hartman, J. D.; Espinoza, N.; Penev, K.; Ciceri, S.; Jordán, A.; Bhatti, W.; Csubry, Z.; Bayliss, D.; Bento, J.; Zhou, G.; Rabus, M.; Mancini, L.; Henning, T.; Schmidt, B.; Tan, T. G.; Tinney, C. G.; Wright, D. J.; Kedziora-Chudczer, L.; Bailey, J.; Suc, V.; Durkan, S.; Lázár, J.; Papp, I.; Sári, P.
2016-12-01
We report the discovery of five new transiting hot-Jupiter planets discovered by the HATSouth survey, HATS-31b through HATS-35b. These planets orbit moderately bright stars with V magnitudes within the range of 11.9-14.4 mag while the planets span a range of masses of 0.88-1.22 {M}{{J}} and have somewhat inflated radii between 1.23 and 1.64 {R}{{J}}. These planets can be classified as typical hot Jupiters, with HATS-31b and HATS-35b being moderately inflated gas giant planets with radii of 1.64+/- 0.22 {R}{{J}} and {1.464}-0.044+0.069 {R}{{J}}, respectively, that can be used to constrain inflation mechanisms. All five systems present a higher Bayesian evidence for a fixed-circular-orbit model than for an eccentric orbit. The orbital periods range from 1.8209993+/- 0.0000016 day for HATS-35b) to 3.377960+/- 0.000012 day for HATS-31b. Additionally, HATS-35b orbits a relatively young F star with an age of 2.13+/- 0.51 Gyr. We discuss the analysis to derive the properties of these systems and compare them in the context of the sample of well-characterized transiting hot Jupiters known to date. The HATSouth network is operated by a collaboration consisting of Princeton University (PU), the Max Planck Institute für Astronomie (MPIA), the Australian National University (ANU), and the Pontificia Universidad Católica de Chile (PUC). The station at Las Campanas Observatory (LCO) of the Carnegie Institute is operated by PU in conjunction with PUC, the station at the High Energy Spectroscopic Survey (H.E.S.S.) site is operated in conjunction with MPIA, and the station at Siding Spring Observatory (SSO) is operated jointly with ANU. Based in part on data collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Based in part on observations made with the MPG 2.2 m and Euler1.2 m Telescopes at the ESO Observatory in La Silla. This paper uses observations obtained with facilities of the Las Cumbres Observatory Global Telescope.
NASA Astrophysics Data System (ADS)
Wyborn, L. A.; Evans, B. J. K.; Pugh, T.; Lescinsky, D. T.; Foster, C.; Uhlherr, A.
2014-12-01
The National Computational Infrastructure (NCI) at the Australian National University (ANU) is a partnership between CSIRO, ANU, Bureau of Meteorology (BoM) and Geoscience Australia. Recent investments in a 1.2 PFlop Supercomputer (Raijin), ~ 20 PB data storage using Lustre filesystems and a 3000 core high performance cloud have created a hybrid platform for higher performance computing and data-intensive science to enable large scale earth and climate systems modelling and analysis. There are > 3000 users actively logging in and > 600 projects on the NCI system. Efficiently scaling and adapting data and software systems to petascale infrastructures requires the collaborative development of an architecture that is designed, programmed and operated to enable users to interactively invoke different forms of in-situ computation over complex and large scale data collections. NCI makes available major and long tail data collections from both the government and research sectors based on six themes: 1) weather, climate and earth system science model simulations, 2) marine and earth observations, 3) geosciences, 4) terrestrial ecosystems, 5) water and hydrology and 6) astronomy, bio and social. Collectively they span the lithosphere, crust, biosphere, hydrosphere, troposphere, and stratosphere. Collections are the operational form for data management and access. Similar data types from individual custodians are managed cohesively. Use of international standards for discovery and interoperability allow complex interactions within and between the collections. This design facilitates a transdisciplinary approach to research and enables a shift from small scale, 'stove-piped' science efforts to large scale, collaborative systems science. This new and complex infrastructure requires a move to shared, globally trusted software frameworks that can be maintained and updated. Workflow engines become essential and need to integrate provenance, versioning, traceability, repeatability and publication. There are also human resource challenges as highly skilled HPC/HPD specialists, specialist programmers, and data scientists are required whose skills can support scaling to the new paradigm of effective and efficient data-intensive earth science analytics on petascale, and soon to be exascale systems.
Imaging photomultiplier array with integrated amplifiers and high-speed USB interfacea)
NASA Astrophysics Data System (ADS)
Blacksell, M.; Wach, J.; Anderson, D.; Howard, J.; Collis, S. M.; Blackwell, B. D.; Andruczyk, D.; James, B. W.
2008-10-01
Multianode photomultiplier tube (PMT) arrays are finding application as convenient high-speed light sensitive devices for plasma imaging. This paper describes the development of a USB-based "plug-n-play" 16-channel PMT camera with 16bits simultaneous acquisition of 16 signal channels at rates up to 2MS/s per channel. The preamplifiers and digital hardware are packaged in a compact housing which incorporates magnetic shielding, on-board generation of the high-voltage PMT bias, an optical filter mount and slits, and F-mount lens adaptor. Triggering, timing, and acquisition are handled by four field-programmable gate arrays (FPGAs) under instruction from a master FPGA controlled by a computer with a LABVIEW interface. We present technical design details and specifications and illustrate performance with high-speed images obtained on the H-1 heliac at the ANU.
Imaging photomultiplier array with integrated amplifiers and high-speed USB interface.
Blacksell, M; Wach, J; Anderson, D; Howard, J; Collis, S M; Blackwell, B D; Andruczyk, D; James, B W
2008-10-01
Multianode photomultiplier tube (PMT) arrays are finding application as convenient high-speed light sensitive devices for plasma imaging. This paper describes the development of a USB-based "plug-n-play" 16-channel PMT camera with 16 bits simultaneous acquisition of 16 signal channels at rates up to 2 MSs per channel. The preamplifiers and digital hardware are packaged in a compact housing which incorporates magnetic shielding, on-board generation of the high-voltage PMT bias, an optical filter mount and slits, and F-mount lens adaptor. Triggering, timing, and acquisition are handled by four field-programmable gate arrays (FPGAs) under instruction from a master FPGA controlled by a computer with a LABVIEW interface. We present technical design details and specifications and illustrate performance with high-speed images obtained on the H-1 heliac at the ANU.
VizieR Online Data Catalog: Cobalt emission in nebular phase spectra (Childress+, 2015)
NASA Astrophysics Data System (ADS)
Childress, M. J.; Hillier, D. J.; Seitenzahl, I.; Sullivan, M.; Maguire, K.; Taubenberger, S.; Scalzo, R.; Ruiter, A.; Blagorodnova, N.; Camacho, Y.; Castillo, J.; Elias-Rosa, N.; Fraser, M.; Gal-Yam, A.; Graham, M.; Howell, D. A.; Inserra, C.; Jha, S. W.; Kumar, S.; Mazzali, P. A.; McCully, C.; Morales-Garoffolo, A.; Pandya, V.; Polshaw, J.; Schmidt, B.; Smartt, S.; Smith, K. W.; Sollerman, J.; Spyromilio, J.; Tucker, B.; Valenti, S.; Walton, N.; Wolf, C.; Yaron, O.; Young, D. R.; Yuan, F.; Zhang, B.
2018-01-01
The analysis in this work relies on a compilation of SN Ia nebular spectra from the literature as well as new observations. We obtained new late-phase (+50=
VizieR Online Data Catalog: The Taurus-Auriga ecosystem. I. (Kraus+, 2017)
NASA Astrophysics Data System (ADS)
Kraus, A. L.; Herczeg, G. J.; Rizzuto, A. C.; Mann, A. W.; Slesnick, C. L.; Carpenter, J. M.; Hillenbrand, L. A.; Mamajek, E. E.
2017-11-01
High-resolution spectroscopic observations for 35 candidates from the surveys of Slesnick+ (2006, J/AJ/132/2665) and Li & Hu (1998, J/A+AS/132/173) were previously obtained with Keck/HIRES on 2006 December 12 and 13 (PIs Carpenter and Slesnick). We downloaded these observations, extracted the spectra, and analyzed them to measure the radial velocity, Hα equivalent width, and Li equivalent width for each object. We observed 32 candidates with the SuperNova Integral Field Spectrograph (SNIFS) on the University of Hawaii 2.2m telescope between 2014 November and 2015 January (PIs Herczeg and Mann). These observations (R~1000) are similar to those described by Mann+ (2015, J/ApJ/804/64), who describe some of the observations and reductions in more detail. See section 3 for further details. (9 data files).
Calypso: a user-friendly web-server for mining and visualizing microbiome-environment interactions.
Zakrzewski, Martha; Proietti, Carla; Ellis, Jonathan J; Hasan, Shihab; Brion, Marie-Jo; Berger, Bernard; Krause, Lutz
2017-03-01
Calypso is an easy-to-use online software suite that allows non-expert users to mine, interpret and compare taxonomic information from metagenomic or 16S rDNA datasets. Calypso has a focus on multivariate statistical approaches that can identify complex environment-microbiome associations. The software enables quantitative visualizations, statistical testing, multivariate analysis, supervised learning, factor analysis, multivariable regression, network analysis and diversity estimates. Comprehensive help pages, tutorials and videos are provided via a wiki page. The web-interface is accessible via http://cgenome.net/calypso/ . The software is programmed in Java, PERL and R and the source code is available from Zenodo ( https://zenodo.org/record/50931 ). The software is freely available for non-commercial users. l.krause@uq.edu.au. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.
VizieR Online Data Catalog: Praesepe members rotational periods from K2 LCs (Douglas+, 2017)
NASA Astrophysics Data System (ADS)
Douglas, S. T.; Agueros, M. A.; Covey, K. R.; Kraus, A.
2018-01-01
We continue to use the Praesepe membership catalog presented in PaperII (Douglas+, 2014, J/ApJ/795/161), which includes 1130 cluster members with membership probabilities Pmem>=50% as calculated by Kraus & Hillenbrand (2007, J/AJ/134/2340) and 39 previously identified members too bright to be included by those authors in their catalog for the cluster. We assign these bright stars Pmem=100%. We also continue to use the photometry and stellar masses presented in Table 5 of Paper II. For most of our analysis, as in that work, we include only the 1099 stars with Pmem>=70%. K2 targeted Praesepe in its Campaign 5. We analyze the resulting long-cadence data for 794 Praesepe members. We present Prot for 677 K2 targets. Of these, 471 are new measurements. (3 data files).
Hawking radiation as tunneling in Schwarzschild anti-de Sitter black hole
NASA Astrophysics Data System (ADS)
Sefiedgar, A. S.; Ashrafinejad, A.
2017-08-01
The Hawking radiation from a (d+1) -dimensional Schwarzschild Anti-de Sitter (SAdS) black hole is investigated within rainbow gravity. Based on the method proposed by Kraus, Parikh and Wilczek, the Hawking radiation is considered as a tunneling process across the horizon. The emission rate of massless particles which are tunneling across the quantum-corrected horizon is calculated. Enforcing the energy conservation law leads to a dynamical geometry. Both the dynamical geometry and the quantum effects of space-time yield some corrections to the emission rate. The corrected radiation spectrum is not purely thermal. The emission rate is related to the changes of modified entropy in rainbow gravity and the corrected thermal spectrum may be consistent with an underlying unitary quantum theory. The correlations between emitted particles are also investigated in order to address the recovery of information.
Optimal joint remote state preparation in the presence of various types of noises
NASA Astrophysics Data System (ADS)
Hop Nguyen, Van; Bich Cao, Thi; Nguyen, Ba An
2017-03-01
A main obstacle faced by any quantum information processing protocol is the noise that degrades the desired coherence/entanglement. In this work we study by means of Kraus operators the effect of four typical types of noises on the quality of joint remote state preparation of a single-qubit state using a three-qubit Greenberger-Horne-Zeilinger-type state as the initial quantum channel. Assuming that two of the three involved qubits independently suffer a type of noise, we derive analytical expressions not only for the optimal averaged fidelities but also for the boundaries in phase space of the domains in which the joint remote state preparation protocol outperforms the classical one. Detailed discussion is given for each of the total 16 noisy scenarios. We also provide physical interpretation for the obtained results and outline possible future topics.
Gleason-Busch theorem for sequential measurements
NASA Astrophysics Data System (ADS)
Flatt, Kieran; Barnett, Stephen M.; Croke, Sarah
2017-12-01
Gleason's theorem is a statement that, given some reasonable assumptions, the Born rule used to calculate probabilities in quantum mechanics is essentially unique [A. M. Gleason, Indiana Univ. Math. J. 6, 885 (1957), 10.1512/iumj.1957.6.56050]. We show that Gleason's theorem contains within it also the structure of sequential measurements, and along with this the state update rule. We give a small set of axioms, which are physically motivated and analogous to those in Busch's proof of Gleason's theorem [P. Busch, Phys. Rev. Lett. 91, 120403 (2003), 10.1103/PhysRevLett.91.120403], from which the familiar Kraus operator form follows. An axiomatic approach has practical relevance as well as fundamental interest, in making clear those assumptions which underlie the security of quantum communication protocols. Interestingly, the two-time formalism is seen to arise naturally in this approach.
Relative L-shell X-ray intensities of Pt, Pb and Bi following ionization by 59.54 keV γ-rays
NASA Astrophysics Data System (ADS)
Dhal, B. B.; Padhi, H. C.
1994-12-01
Relative L-shell X-ray intensities of Pt, Pb and Bi have been measured following ionization by 59.54 keV photons from an 241 Am point source. The measured ratios have been compared with the theoretical ratios estimated using the photoionization cross-sections of Scofield and different decay yield data. The comparison shows good agreement for Pb and Bi with the decay yield data of Krause, but the decay yield data of Xu and Xu overestimates the ratios, particularly for the {I γ}/{I α} ratio. Our results for Pb and Bi with improved error limits also agree with the previous experimental results of Shatendra et al. For Pt our present results are found to lie between the two theoretical results obtained by using different sets of decay yield data.
CICADA -- Configurable Instrument Control and Data Acquisition
NASA Astrophysics Data System (ADS)
Young, Peter J.; Roberts, William H.; Sebo, Kim M.
CICADA (Young et al. 1997) is a multi-process, distributed application for the control of astronomical data acquisition systems. It comprises elements that control the operation of, and data flow from CCD camera systems; and the operation of telescope instrument control systems. CICADA can be used to dynamically configure support for astronomical instruments that can be made up of multiple cameras and multiple instrument controllers. Each camera is described by a hierarchy of parts that are each individually configured and linked together. Most of CICADA is written in C++ and much of the configurability of CICADA comes from the use of inheritance and polymorphism. An example of a multiple part instrument configuration -- a wide field imager (WFI) -- is described here. WFI, presently under construction, is made up of eight 2k x 4k CCDs with dual SDSU II controllers and will be used at Siding Spring's ANU 40in and AAO 3.9m telescopes.
[1400 hours of analysis with Freud: Viktor von Dirsztay. A biographical sketch].
May, Ulrike
2010-01-01
On the basis of mostly unpublished sources, the author reconstructs the life of the Hungarian writer Viktor von Dirsztay (1884?-1935) who was personally acquainted with many expressionist artists and writers, e. g. with Karl Kraus, Oskar Kokoschka, Herwarth Walden, Walter Hasenclever, Hermann Broch and Arthur Schnitzler. This association puts Freud into closer proximity with the cultural avantgarde of his times than previously realized. Between 1910 and 1920 Dirsztay underwent several phases of analysis with Freud; then he was treated by Theodor Reik. The overall length of his analysis with Freud is almost unparalleled. The article discusses whether and in which way Dirsztay's writings might have been influenced by his analyses and how Freud and Reik might have drawn upon their experiences with this patient. It is argued that likely references can be discovered in both authors' theories of masochism. There is an intriguing late remark of Dirsztay's that he was "ruined by analysis".
Tycho's Star Shines in Gamma Rays
2017-12-08
NASA image relase December 13, 2011 Gamma-rays detected by Fermi's LAT show that the remnant of Tycho's supernova shines in the highest-energy form of light. This portrait of the shattered star includes gamma rays (magenta), X-rays (yellow, green, and blue), infrared (red) and optical data. Credit: Gamma ray, NASA/DOE/Fermi LAT Collaboration; X-ray, NASA/CXC/SAO; Infrared, NASA/JPL-Caltech; Optical, MPIA, Calar Alto, O. Krause et al. and DSS To read more go to: www.nasa.gov/mission_pages/GLAST/news/tycho-star.html 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 Astrophysics Data System (ADS)
Ren, Chunye; Parel, Jean-Marie A.
1993-06-01
Scientists have searched every discipline to find effective methods of treating blindness, such as using aids based on conversion of the optical image, to auditory or tactile stimuli. However, the limited performance of such equipment and difficulties in training patients have seriously hampered practical applications. A great edification has been given by the discovery of Foerster (1929) and Krause & Schum (1931), who found that the electrical stimulation of the visual cortex evokes the perception of a small spot of light called `phosphene' in both blind and sighted subjects. According to this principle, it is possible to invite artificial vision by using stimulation with electrodes placed on the vision neural system, thereby developing a prosthesis for the blind that might be of value in reading and mobility. In fact, a number of investigators have already exploited this phenomena to produce a functional visual prosthesis, bringing about great advances in this area.
NASA Astrophysics Data System (ADS)
Dietz, Laura
The Science Teaching Advancement through Modeling Physical Science (STAMPS) professional development workshop was evaluated for effectiveness in improving teachers' and students' content knowledge. Previous research has shown modeling to be an effective method of instruction for improving student and teacher content knowledge, evidenced by assessment scores. Data includes teacher scores on the Force Concept Inventory (FCI; Hestenes, Wells, & Swackhamer, 1992) and the Chemistry Concept Inventory (CCI; Jenkins, Birk, Bauer, Krause, & Pavelich, 2004), as well as student scores on a physics and chemistry assessment. Quantitative data is supported by teacher responses to a post workshop survey and classroom observations. Evaluation of the data shows that the STAMPS professional development workshop was successful in improving both student and teacher content knowledge. Conclusions and suggestions for future study are also included.
Divergence-free approach for obtaining decompositions of quantum-optical processes
NASA Astrophysics Data System (ADS)
Sabapathy, K. K.; Ivan, J. S.; García-Patrón, R.; Simon, R.
2018-02-01
Operator-sum representations of quantum channels can be obtained by applying the channel to one subsystem of a maximally entangled state and deploying the channel-state isomorphism. However, for continuous-variable systems, such schemes contain natural divergences since the maximally entangled state is ill defined. We introduce a method that avoids such divergences by utilizing finitely entangled (squeezed) states and then taking the limit of arbitrary large squeezing. Using this method, we derive an operator-sum representation for all single-mode bosonic Gaussian channels where a unique feature is that both quantum-limited and noisy channels are treated on an equal footing. This technique facilitates a proof that the rank-1 Kraus decomposition for Gaussian channels at its respective entanglement-breaking thresholds, obtained in the overcomplete coherent-state basis, is unique. The methods could have applications to simulation of continuous-variable channels.
2013-01-01
Background Disappointing results from clinical trials of disease-modifying interventions for Alzheimer’s dementia (AD), along with reliable identification of modifiable risk factors in mid life from epidemiological studies, have contributed to calls to invest in risk-reduction interventions. It is also well known that AD-related pathological processes begin more than a decade before the development of clinical signs. These observations suggest that lifestyle interventions might be most effective when targeting non-symptomatic adults at risk of AD. To date, however, the few dementia risk-reduction programs available have targeted individual risk factors and/or were restricted to clinical settings. The current study describes the development of an evidence-based, theoretically-driven multidomain intervention to reduce AD risk in adults at risk. Method The design of Body Brain Life (BBL) is a randomized controlled trial (RCT) to evaluate a 12-week online AD risk-reduction intervention. Eligible participants with several modifiable risk factors on the Australian National University (ANU) AD Risk Index (ANU-ADRI) are randomly allocated to an online only group, an online and face-to-face group, or an active control group. We aim to recruit 180 participants, to undergo a comprehensive cognitive and physical assessment at baseline, post-intervention, and 6-month follow-up assessment. The intervention comprises seven online modules (dementia literacy, risk factor education, engagement in physical, social, and cognitive lifestyles, nutrition, and health monitoring) designed using contemporary models of health behavior change. Discussion The BBL program is a novel online intervention to reduce the risk of AD in middle-aged adults at risk. The trial is currently under way. It is hypothesized that participants in the intervention arms will make lifestyle changes in several domains, and that this will lead to a reduction in their AD risk profile. We also expect to show that health behavior change is underpinned by changes in psychological determinants of behavior. If successful, the findings will contribute to the development of further dementia risk reduction interventions, and thus contribute to the urgent need to lower dementia risk factors in the population to alter future projections of disease prevalence. Longer follow-up of BBL participants and replications using large samples are required to examine whether reduction in AD risk factors will be associated with reduced prevalence. Trial registration Reg. no. ACTRN12612000147886 PMID:23442574
Geomagnetic Workshop, Canberra
NASA Astrophysics Data System (ADS)
Barton, C. E.; Lilley, F. E. M.; Milligan, P. R.
On May 14-15, 1985, 63 discerning geomagnetists flocked to Canberra to attend the Geomagnetic Workshop coorganized by the Australian Bureau of Mineral Resources (BMR) and the Research School of Earth Sciences, Australian National University (ANU). With an aurorally glowing cast that included an International Association of Geomagnetism and Aeronomy (IAGA) president, former president, and division chairman, the Oriental Magneto-Banquet (which was the center of the meeting), was assured of success. As a cunning ploy to mask the true nature of this gastronomic extravagance from the probings of income tax departments, a presentation of scientific papers on Australian geomagnetism in its global setting was arranged.The Australian region, including New Zealand, Papua New Guinea, Indonesia, and a large sector of the Antarctic, covers one eighth of the Earth's surface and historically has played an important role in the study of geomagnetism. The region contains both the south magnetic and geomagnetic poles, and two Australian Antarctic stations (Casey and Davis) are situated in the region of the south polar cusp (see Figure 1).
Low Energy Positron Scattering, Transport, and Applications
NASA Astrophysics Data System (ADS)
Buckman, Stephen
2017-04-01
Relatively intense, high energy-resolution beams of low-energy positrons are now available through the use of buffer-gas (Surko) traps. These have led to measurements of interaction cross sections for a broad range of atoms and molecules, including molecules of biological interest. The increased energy resolution, and experimental techniques developed for scattering in strong magnetic fields has also enabled highly accurate measurements of discrete excitation processes such as electronic and vibrational excitation, positronium formation and ionization in a range of atomic and molecular species. This talk will review some of these measurements and discuss their application in new and sophisticated models of positron transport which aim, for example, to provide a better understanding of the atomic and molecular processes which occur when positrons are emitted in the body during a Positron Emission Tomography scan. This work is part of a broad collaboration between the ANU (James Sullivan, Joshua Machacek), Flinders University (Michael Brunger), James Cook University (Ronald White and co-workers) CSIC Madrid (Gustavo Garcia) and the Institute of Physics, Belgrade (Zoran Petrovic and colleagues).
Quantum Cause of Gravity Waves and Dark Matter
NASA Astrophysics Data System (ADS)
Goradia, Shantilal; Goradia Team
2016-09-01
Per Einstein's theory mass tells space how to curve and space tells mass how to move. How do they tell''? The question boils down to information created by quantum particles blinking ON and OFF analogous to `Ying and Yang' or some more complex ways that may include dark matter. If not, what creates curvature of space-time? Consciousness, dark matter, quantum physics, uncertainty principle, constants of nature like strong coupling, fine structure constant, cosmological constant introduced by Einstein, information, gravitation etc. are fundamentally consequences of that ONE TOE. Vedic philosophers, who impressed Schrodinger so much, called it ATMA split in the categories of AnuAtma (particle soul), JivAtma (life soul) and ParamAtma (Omnipresent soul) which we relate to quantum physics, biology and cosmology. There is no separate TOE for any one thing. The long range relativistic propagations of the strong and weak couplings of the microscopic black holes in are just gravity waves. What else could they be?
NASA Astrophysics Data System (ADS)
Sydoff, Marie; Stenström, Kristina
2010-04-01
The Department of Physics at Lund University is participating in a European Union project called EUMAPP (European Union Microdose AMS Partnership Programme), in which sample preparation and accelerator mass spectrometry (AMS) measurements of biological samples from microdosing studies have been made. This paper describes a simplified method of converting biological samples to solid graphite for 14C analysis with AMS. The method is based on online combustion of the samples, and reduction of CO 2 in septa-sealed vials. The septa-sealed vials and disposable materials are used to eliminate sample cross-contamination. Measurements of ANU and Ox I standards show deviations of 2% and 3%, respectively, relative to reference values. This level of accuracy is sufficient for biological samples from microdosing studies. Since the method has very few handling steps from sample to graphite, the risk of failure during the sample preparation process is minimized, making the method easy to use in routine preparation of samples.
New Proposal of Setal Homology in Schizomida and Revision of Surazomus (Hubbardiidae) from Ecuador.
Manzanilla, Osvaldo Villarreal; de Miranda, Gustavo Silva; Giupponi, Alessandro Ponce de Leão
2016-01-01
The homology of three somatic systems in Schizomida is studied yielding the following results: (1) proposal of homology and chaetotaxy of abdominal setae in Surazomus; (2) revision of the cheliceral chaetotaxy in Schizomida, with suggestion of new homology scheme between Hubbardiidae and Protoschizomidae, description of a new group of setae in Hubbardiinae (G7), and division of setae group 5 in two subgroups, G5A and G5B; (3) proposal of segmental homology between trimerous and tetramerous female flagellum in Hubbardiinae with association of segment III of tri-segmented species to segments III + IV of tetra-segmented species. Considerations about the dorsal microsetae on the male flagellum are made. The genus Surazomus in Ecuador is revised. The sympatric species Surazomus palenque sp. nov. and S. kitu sp. nov. (Ecuador, Pichincha) are described and illustrated. The female of S. cuenca (Rowland and Reddell, 1979) is described, with two new distributional records for the species. Surazomus cumbalensis (Kraus, 1957) is recorded for the first time from Ecuador (Pichincha).
Parametric Quantum Search Algorithm as Quantum Walk: A Quantum Simulation
NASA Astrophysics Data System (ADS)
Ellinas, Demosthenes; Konstandakis, Christos
2016-02-01
Parametric quantum search algorithm (PQSA) is a form of quantum search that results by relaxing the unitarity of the original algorithm. PQSA can naturally be cast in the form of quantum walk, by means of the formalism of oracle algebra. This is due to the fact that the completely positive trace preserving search map used by PQSA, admits a unitarization (unitary dilation) a la quantum walk, at the expense of introducing auxiliary quantum coin-qubit space. The ensuing QW describes a process of spiral motion, chosen to be driven by two unitary Kraus generators, generating planar rotations of Bloch vector around an axis. The quadratic acceleration of quantum search translates into an equivalent quadratic saving of the number of coin qubits in the QW analogue. The associated to QW model Hamiltonian operator is obtained and is shown to represent a multi-particle long-range interacting quantum system that simulates parametric search. Finally, the relation of PQSA-QW simulator to the QW search algorithm is elucidated.
Modeling Planet-Building Stellar Disks with Radiative Transfer Code
NASA Astrophysics Data System (ADS)
Swearingen, Jeremy R.; Sitko, Michael L.; Whitney, Barbara; Grady, Carol A.; Wagner, Kevin Robert; Champney, Elizabeth H.; Johnson, Alexa N.; Warren, Chelsea C.; Russell, Ray W.; Hammel, Heidi B.; Lisse, Casey M.; Cure, Michel; Kraus, Stefan; Fukagawa, Misato; Calvet, Nuria; Espaillat, Catherine; Monnier, John D.; Millan-Gabet, Rafael; Wilner, David J.
2015-01-01
Understanding the nature of the many planetary systems found outside of our own solar system cannot be completed without knowledge of the beginnings these systems. By detecting planets in very young systems and modeling the disks of material around stars from which they form, we can gain a better understanding of planetary origin and evolution. The efforts presented here have been in modeling two pre-transitional disk systems using a radiative transfer code. With the first of these systems, V1247 Ori, a model that fits the spectral energy distribution (SED) well and whose parameters are consistent with existing interferometry data (Kraus et al 2013) has been achieved. The second of these two systems, SAO 206462, has presented a different set of challenges but encouraging SED agreement between the model and known data gives hope that the model can produce images that can be used in future interferometry work. This work was supported by NASA ADAP grant NNX09AC73G, and the IR&D program at The Aerospace Corporation.
Duality quantum algorithm efficiently simulates open quantum systems
Wei, Shi-Jie; Ruan, Dong; Long, Gui-Lu
2016-01-01
Because of inevitable coupling with the environment, nearly all practical quantum systems are open system, where the evolution is not necessarily unitary. In this paper, we propose a duality quantum algorithm for simulating Hamiltonian evolution of an open quantum system. In contrast to unitary evolution in a usual quantum computer, the evolution operator in a duality quantum computer is a linear combination of unitary operators. In this duality quantum algorithm, the time evolution of the open quantum system is realized by using Kraus operators which is naturally implemented in duality quantum computer. This duality quantum algorithm has two distinct advantages compared to existing quantum simulation algorithms with unitary evolution operations. Firstly, the query complexity of the algorithm is O(d3) in contrast to O(d4) in existing unitary simulation algorithm, where d is the dimension of the open quantum system. Secondly, By using a truncated Taylor series of the evolution operators, this duality quantum algorithm provides an exponential improvement in precision compared with previous unitary simulation algorithm. PMID:27464855
Krysko, Kenneth L.; Hart, Kristen M.; Smith, Brian J.; Selby, Thomas H.; Cherkiss, Michael S.; Coutu, Nicholas T.; Reichart, Rebecca M.; Nuñez, Leroy P.; Mazzotti, Frank J.; Snow, Ray W.
2012-01-01
The Burmese Python, Python bivittatus Kuhl 1820 (Squamata: Pythonidae), is indigenous to northern India,east to southern China, and south to Vietnam and a few islands in Indonesia (Barker and Barker 2008, Reed and Rodda 2009). This species has been introduced since at least 1979 in southern Florida, USA, where it likely began reproducing and became established during the 1980s (Meshaka et al. 2000, Snowet al. 2007b,Kraus 2009, Krysko et al. 2011, Willson et al. 2011). Python bivittatus has been documented in Florida consuming a variety of mammals and birds, and the American Alligator(Alligator mississippiensis) (Snowet al. 2007a, 2007b; Harvey et al. 2008; Rochford et al. 2010b; Holbrook and Chesnes 2011), many of which are protected species. Herein, we provide details on two of the largest known wild P. bivittatus in Florida to date, including current records on length,mass,clutch size, and diet.
NASA Astrophysics Data System (ADS)
Liu, Molin; Lu, Junwang
2011-05-01
Motivated by recent logarithmic entropy of Hořava-Lifshitz gravity, we investigate Hawking radiation for Kehagias-Sfetsos black hole from tunneling perspective. After considering the effect of self-gravitation, we calculate the emission rate and entropy of quantum tunneling by using Kraus-Parikh-Wilczek method. Meanwhile, both massless and massive particles are considered in this Letter. Interestingly, two types tunneling particles have the same emission rate Γ and entropy Sb whose analytical formulae are Γ=exp[π(rin2-rout2)/2+π/αln rin/rout] and Sb=A/4+π/αln(A/4), respectively. Here, α is the Hořava-Lifshitz field parameter. The results show that the logarithmic entropy of Hořava-Lifshitz gravity could be explained well by the self-gravitation, which is totally different from other methods. The study of this semiclassical tunneling process may shed light on understanding the Hořava-Lifshitz gravity.
NASA Astrophysics Data System (ADS)
Benson, S. M.; Hingerl, F.; Pini, R.
2013-12-01
New imaging techniques and approaches are providing unparalleled insight into the influence of sub-core scale heterogeneities on single and multiphase flows. Quantification of sub core-scale porosity, permeability, and even capillary pressure curves at a spatial scale of about 1-10 cubic millimeters is now possible. This scale provides a critical link in the continuum of spatial scales needed to link pore-scale processes to core-scale and field scale flow and transport. Data from such studies can be used to directly test the veracity of models for flow and transport in heterogeneous rocks, provide data for multi-stage upscaling, and reveal insights about physical/chemical processes heretofore neglected. Here we present data from three emerging techniques capable of imaging and quantifying transport properties and phenomena at the sub-core scale: magnetic resonance imaging (MRI); positron emission tomography (PET); and X-Ray CT scanning. Direct imaging of spatially resolved fluid velocities and porosity is possible with MRI (Romanenko et al., 2012). These data can be inverted to provide permeability and porosity maps at a spatial scale of ~10 cubic millimeter. PET imaging can be used to track movement of a radioactive tracer through a rock and simultaneously measure effluent tracer concentrations at a similar resolution (Boutchko et al., 2012). X-ray CT scanning of multiphase flow experiments can be used to measure capillary pressure curves and through scaling relationships, to calculate permeability at a scale of about 1 cubic millimeters(Krause et al., 2011; Pini et al., 2013). Strengths and shortcomings of these techniques are discussed--along with the benefits of combining them. Together these techniques provide a new platform from which to probe more deeply the ubiquitous influence of heterogeneity on subsurface flow and transport processes, and ultimately improve predictions of subsurface transport. Boutchk et al., 2012. Imaging and modeling of flow in porous media using clinical nuclear emission tomography systems and computational fluid dynamics. Journal of Applied geophysics, 76, 74-81. Krause, M.H., J.C. Perrin, and S.M. Benson, 2011. Modeling permeability distributions in a sandstone core for history matching core flood experiments, SPE Journal, 16, 768-777. Pini R. and Benson S., Characterization and scaling of meso-scale heterogeneities in sandstones. Geophysical Research Letters, 2013, 40. Romanenko, K., and Balscom, Permeability mapping in naturally heterogeneous sandstone cores with magnetization prepared SPRITE, 2012, 58, 3916-3926.
Could the Craters on the Mid-Sized Moons of Saturn Have Been Made by Satellite Debris?
NASA Astrophysics Data System (ADS)
Dones, Henry C. Luke; Alvarellos, Jose; Bierhaus, Edward B.; Bottke, William; Cuk, Matija; Hamill, Patrick; Nesvorny, David; Robbins, Stuart J.; Zahnle, Kevin
2016-10-01
Saturn's mid-sized moons have usually been assumed to be primordial. However, Charnoz et al. (2011) and Crida and Charnoz (2012) showed that the steep trend of mass vs. distance of the moons out to Rhea is consistent with the spreading of an early massive ring (e.g., Canup 2010) beyond Saturn's Roche limit. In this model, these moons would be billions of years old, but with Mimas forming perhaps 1 Gyr after Rhea.Cuk et al. (2016) investigated the dynamical evolution of the, mid-sized saturnian moons due to tides. They infer that the moons have migrated little. Tethys and Dione probably did not cross their 3:2 resonance, but the system likely did cross a Dione-Rhea 5:3 resonance and a Tethys-Dione secular resonance. These crossings would have happened recently; for Q = 1500 (Lainey et al. 2012), within the past 100 Myr. Cuk et al. suggested that a previous generation of moons underwent an orbital instability, perhaps due to a solar evection resonance, leading to catastrophic collisions between them (Movshovitz et al. 2016). Today's moons would have reaccreted from the debris. This model implies that most craters on the moons were formed by this debris, with impacts taking place at much lower speeds than applies for impacts by comets.Many crater properties, such as the depth-to-diameter ratio (Bray and Schenk 2015) and the amount of melting and vaporization (Kraus et al. 2011), depend on the impact velocity. We will discuss how measurements of craters in Cassini images of saturnian moons can be used to distinguish between the Cuk et al. scenario and the view in which the largest craters are made by comets and planetocentric debris makes only smaller craters (Alvarellos et al. 2005).We thank the Cassini Data Analysis Program for support and Amy Barr Mlinar for discussions.Alvarellos, J.L., Zahnle, K.J., Dobrovolskis, A.R., Hamill,P. (2005). Icarus 178, 104Bray, V.J., Schenk, P.M. (2015). Icarus 246, 156Canup, R.M. (2010). Nature 468, 943Charnoz, S., et al. (2011). Icarus 216, 535Crida, A., Charnoz, S. (2012). Science 338, 1196Cuk, M., Dones, L., Nesvorny, D. (2016). Astrophys. J. 820:97Kraus, R.G., Senft, L.E., Stewart, S.T. (2011). Icarus 214, 724Lainey, V., et al. (2012). Astrophys. J. 752:14Movshovitz, N., et al. (2016). Icarus 275, 85
NASA Astrophysics Data System (ADS)
Gravitis, J.; Abolins, J.
2013-10-01
Exhausting of world resources, increasing pollution, and climate change are compelling the shift of the world economy from continuous growth to a kind of economy based on integration of technologies into zero emissions production systems. Transition from non-renewable fossil resources to renewable resources provided by solar radiation and the current processes in biosphere is seen in the bio-refinery approach - replacing crude oil refineries by biomass refineries. Biotechnology and nano-technologies are getting accepted as important players along with conventional biomass refinery technologies. Systems design is a significant element in the integration of bio-refinery technologies in clusters. A number of case-studies, steam explosion auto-hydrolysis (SEA) in particular, are reviewed to demonstrate conversion of biomass into value-added chemicals and fuels. Analysis of energy flows is made as part of modelling the SEA processes, the eMergy (energy memory) approach and sustainability indices being applied to assess environmental impacts. Resursu izsīkums, vides piesārņojums un globāla mēroga klimatiskās izmaiņas ir civilizācijas izdzīvošanai būtiski faktori, kas virza pasaules ekonomikas pārmaiņas, atsakoties no nepārtrauktas izaugsmes idejas par labu tādai ekonomikai, kas balstās uz atjaunojošamies resursiem un dažādu tehnoloģiju integrācijemisiju principam atbilstošās ražošanas sistēmās. Saules radiācijas ierosinātajos planētas biosfērā notiekošajos procesos radīto organisko vielu pārstrādes kompleksi, kas operē ievērojot sabalansētu nulles emisiju principu, tiek uzlūkoti kā tās ekonomiskās (ražošanas) struktūras, kurām jānodrošina pāreja uz atjaunojošos resursu izmantošanu, aizstājot esošās fosilo resursu (naftas, ogļu) pārstrādes rūpnīcas. Līdzās jau apgūtajām biomasas rafinēšanas tehnoloģijām svarīga un pieaugoša loma ekonomiskās sistēmas resursu bāzes nomaiņā ir bio- un nanotehnoloģijām, bet ražošanas sistēmu projektēšanai - biomasas konversijas tehnoloģiju klasterizācijā. Aplūkojot virkni konkrētu tehnoloģisko risinājumu, TSA - biomasas autohidrolīzi tvaika sprādzienā tai skaitā, iztirzātas ar biomasas konversiju, izmantošanu un augstas pievienotās vērtības produktiem - ķīmiskiem savienojumiem un degvielām, saistītās ekololoģiskās un energoefektivitātes problēmas. Uzsverot biomasas TSA pirmapstrādes universālo nozīmi dažādo tehnoloģisko kompleksu struktūrā, aplūkota TSA ietekme uz vidi, demonstrējot eMerģijas (enerģētiskās atmiņas) pieeju un "ilgtspējas" indeksu izmantošanu. Lai gan pie sasniegtā tehnoloģiskās attīstības līmeņa un patreizējiem fosilo enerģijas nesēju patēriņa tempiem nav iespējams tos pilnībā aizstāt ar bioenerģiju, bioenerģijas sektora tehnoloģiju pilnveidošana ir svarīga arī bioresursu racionālas izmantošanas un citos aspektos. Latvijas enerģētiskās neatkarības kontekstā būtiska nozīme ir tradicionālo bioenerģijas resursu izmantošanas efektivitātes celšanai un inovatīvo bioenerģijas tehnoloģiju valstiskam atbalstam.u nulles
Obituary: James C. Kemp, 1927-1988
NASA Astrophysics Data System (ADS)
Milone, E. F.
2009-01-01
James C. Kemp was born in Detroit, Michigan on 9 February 1927, and died in Eugene, Oregon, on 29 March 1988. He went to high school in Mexico City and did undergraduate studies at the University of Michigan and University of California at Berkeley. Kemp was an active observational astronomer, having migrated from earlier interests in Slavic languages, in which he majored, electrical engineering, and physics. He obtained a PhD in electrical engineering at Berkeley in 1960 and did post-doctoral work there with Erwin Hahn on spin resonance. He went to the University of Oregon in 1961 and conducted research in magneto-optics, developing, in the process, a piezo-optical birefringence modulator to measure circular polarization. The modulator is described by Tinbergen (1996). Kemp explored new areas as he measured magnetic fields in the sunspots with polarized infrared light, and developed polarimeters and photometers to study the behavior of such astronomical sources as white dwarfs, the relativistic jets of binary SS 433, the x-ray binary Cyg X-1, and the bright eclipsing binaries Algol and e Aurigae on the 61- and, later, 81-cm telescope at the Pine Mountain Observatory, of which Kemp was director until his death from cancer. His measurement of circularly polarization in the continuum light of the white dwarf GJ 742 (Grw +70∘ 8247, Kemp et al. 1970b) was an important discovery, and through his study of Algol (Kemp et al. 1983; Wilson & Liou 1993), he appears to have been the first to discover the limb polarization in eclipsing binaries predicted by Chandrasekhar (1946ab). Although it has taken twenty years for the BAAS to publish his obituary notice, it is somewhat appropriate that his former student, Gary Henson, who provided much of the background for this article, is involved with a polarimetry team to observe and analyze data from e Aurigae, as it approaches ingress of the next primary minimum beginning summer, 2009. The author acknowledges with gratitude the additional assistance of T. A. Clark and R. E. Wilson in preparing this article. Representative Publications and References: Chandrasekhar, S. 1946a, ApJ, 103, 361. Chandrasekhar, S. 1946b, ApJ, 104, 110. Donnelly, R. J. 1989, "James C. Kemp," Physics Today, 42, 94. Henson, G. D. 2008, private communication. Kemp, J. C., 1969, "Piezo-optical birefringence modulators: new use for a long-known effect," J. Opt. Soc. Am., 59, 950. Kemp, J. C. and Henson, G. D., 1983, "Broad-band circular polarization of sunspots, 0.27-4.5 microns," ApJ, 266, L69. Kemp, J. C., Macek, J. H., Nehring, F. W. 1984, "Induced atomic orientation, an efficient mechanism for magnetic circular polarization," ApJ, 278, 863. Kemp, J. C., Swedlund, J. B., and Evans, B. D. 1970a, "Magnetoemission from incandescent sources," Phys. Rev. Let., 24, 1211. Kemp. J. C., Swedlund, J. B., Landstreet, J. D., and Angel, J. R. P. 1970b, "Discovery of Circularly Polarized Light from a White Dwarf," ApJL, 161, L77. Kemp, J. C., Henson, G. D., Steiner, C. T., Powell, E. R. 1987, "The optical polarization of the Sun measured at a sensitivity of parts in ten million," Nature, 326, 270. Kemp, J. C., Henson, G. D., Barbour, M. S., Kraus, D. J., and Collins, G. W. 1983, "Discovery of Eclipse Polarization in Algol," ApJ, 273, L85. Kemp, J. C., Henson, G. D., Kraus, D. J., Beardsley, I. S., Carroll, L. C., Ake, T. B., Simon, T., and Collins, G. W. 1986, "Epsilon Aurigae: Polarization, Light Curves, and Geometry of the 1982-1984 Eclipse," ApJL, 300, L11. Kemp, J. C., Henson, G. D., Kraus, D. J., Carroll, L. C., Beardsley, I. S., Takagishi, K., Jugaku, J., Matsuoka, M., Leibowitz, E. M., Mazeh, T., and Mendelson, H. 1986, "SS 433: A 6 Year Photometric Record," ApJ, 305, 805. Tinbergen, J. 1996, Astronomical Polarimetry, (Cambridge: Cambridge University Press), pp. 95-96. Wilson, R. E., and Liou, J.-C. 1993, ApJ, 413, 670.
Imin, Nijat; De Jong, Femke; Mathesius, Ulrike; van Noorden, Giel; Saeed, Nasir A; Wang, Xin-Ding; Rose, Ray J; Rolfe, Barry G
2004-07-01
Using a combination of two-dimensional gel electrophoresis (2-DE) protein mapping and mass spectrometry (MS) analysis, we have established proteome reference maps of Medicago truncatula embryogenic tissue culture cells. The cultures were generated from single protoplasts, which provided a relatively homogeneous cell population. We used these to analyze protein expression at the globular stages of somatic embryogenesis, which is the earliest morphogenetic embryonic stage. Over 3000 proteins could reproducibly be resolved over a pI range of 4-11. Three hundred and twelve protein spots were extracted from colloidal Coomassie Blue-stained 2-DE gels and analyzed by matrix-assisted laser desorption/ionization-time of flight MS analysis and tandem MS sequencing. This enabled the identification of 169 protein spots representing 128 unique gene products using a publicly available expressed sequence tag database and the MASCOT search engine. These reference maps will be valuable for the investigation of the molecular events which occur during somatic embryogenesis in M. truncatula. The proteome reference maps and supplementary materials will be available and updated for public access at http://semele.anu.edu.au/.
Helicons, History, High Technology and Heliacs
NASA Astrophysics Data System (ADS)
Boswell, Rod
1998-11-01
Helicon waves depend basically on the Hall effect and propagate between the ion and electron gyro frequencies: they are whistlers masquerading under another name hence their history goes back to the great war and subsequently involved such people as Appleton, Hartree and Storey. Considerable experimental and theoretical research was carried out on linear propagation during the 1960's and at the end of the decade it was discovered that the wave could actually heat the plasma electrons and increase the ionisation rate considerably. Nothing much happened during the 1970's but in the early 1980's it was realised that this high density source could be used for processing thin films and an increasing number of papers were published, which continues to this day. The first experiments on using helicons to create and heat toroidal plasmas were carried out at the end of the 1980's in a small heliac. Recent experiments with helicon excitation in the large heliac H1 at the ANU have shown that the ion temperature increases with the wave power. This mystery is being actively investigated.
NASA Astrophysics Data System (ADS)
Gibson, Stephen; Laws, Benjamin; Suits, Arthur; Fernando, Ravin; Field, Robert W.
2015-06-01
In 1989 the Lineberger group observed S0 vinylidene in the negative ion photoelectron spectrum. Excess widths were interpreted by some as indicating a sub-picosecond lifetime for vinylidene. 1998 Coulomb explosion experiments showed that vinylidene character survives for at least 3.5 μs. Chirped Pulse mm-Wave spectra showed that 193 nm photolysis of Vinyl Cyanide produces many vibrational levels of HCN and HNC but no trace of vinylidene or local-bender excited acetylene. David Perry's and Michel Herman's effective Hamiltonian model for local-bender acetylene showed that IVR is complete at J approximately 100. Observation of long-lived vinylidene requires formation at low-J. Photodetachment of an electron from the Vinylidene negative ion deposits negligible angular momentum in the C2H2 moiety. The high-resolution negative-ion Photoelectron Velocity Map Imaging spectrometer at ANU reveals vinylidene with strongly vibration-dependent β asymmetry parameters. Infrared Multi-Photon Dissociation of Vinyl Chloride in the Wayne State Velocity Map Imaging spectrometer reveals rotationally and vibrationally cold HCl, presumably the 3-center photofragmentation co-product of rotationally cold vinylidene. The mechanism of vinylidene-acetylene isomerization is emerging...
Mass media and heterogeneous bounds of confidence in continuous opinion dynamics
NASA Astrophysics Data System (ADS)
Pineda, M.; Buendía, G. M.
2015-02-01
This work focuses on the effects of an external mass media on continuous opinion dynamics with heterogeneous bounds of confidence. We modified the original Deffuant et al. and Hegselmann and Krause models to incorporate both, an external mass media and a heterogeneous distribution of confidence levels. We analysed two cases, one where only two bounds of confidence are taken into account, and other where each individual of the system has her/his own characteristic level of confidence. We found that, in the absence of mass media, diversity of bounds of confidence can improve the capacity of the systems to reach consensus. We show that the persuasion capacity of the external message is optimal for intermediate levels of heterogeneity. Our simulations also show the existence, for certain parameter values, of a counter-intuitive effect in which the persuasion capacity of the mass media decreases if the mass media intensity is too large. We discuss similarities and differences between the two heterogeneous versions of these continuous opinion dynamic models under the influence of mass media.
Moras, Karla
2005-03-01
Recent growth of "managed" mental health care in the United States has spawned huge demand for products that draw on one of psychology's most well developed subdisciplines, tests and measurement. The commercial potential of mental health assessment instruments intended for widespread use, to meet what Kraus, Seligman, and Jordan (this volume) describe as "an industry-wide surge in outcome evaluations in naturalistic ... settings," necessarily raises conflict of interest dilemmas for those who develop and market them. The American Psychological Association has devoted intensive effort to the preceding issue as it pertains to other aspects of the science and practice of clinical psychology. Comparable attention has not been focused recently on the development and marketing of assessment instruments. This Comment highlights the issue and suggests types of self-regulatory actions that might be taken, e.g., requiring and publishing full disclosure statements of authors' relationships to companies that market instruments like the Treatment Outcome Package in psychometric articles in which they are evaluated. 2004 Wiley Periodicals, Inc.
Plasma versus Drude Modeling of the Casimir Force: Beyond the Proximity Force Approximation
NASA Astrophysics Data System (ADS)
Hartmann, Michael; Ingold, Gert-Ludwig; Neto, Paulo A. Maia
2017-07-01
We calculate the Casimir force and its gradient between a spherical and a planar gold surface. Significant numerical improvements allow us to extend the range of accessible parameters into the experimental regime. We compare our numerically exact results with those obtained within the proximity force approximation (PFA) employed in the analysis of all Casimir force experiments reported in the literature so far. Special attention is paid to the difference between the Drude model and the dissipationless plasma model at zero frequency. It is found that the correction to PFA is too small to explain the discrepancy between the experimental data and the PFA result based on the Drude model. However, it turns out that for the plasma model, the corrections to PFA lie well outside the experimental bound obtained by probing the variation of the force gradient with the sphere radius [D. E. Krause et al., Phys. Rev. Lett. 98, 050403 (2007), 10.1103/PhysRevLett.98.050403]. The corresponding corrections based on the Drude model are significantly smaller but still in violation of the experimental bound for small distances between plane and sphere.
Neolithic and Medieval virus genomes reveal complex evolution of Hepatitis B.
Krause-Kyora, Ben; Susat, Julian; Key, Felix M; Kühnert, Denise; Bosse, Esther; Immel, Alexander; Rinne, Christoph; Kornell, Sabin-Christin; Yepes, Diego; Franzenburg, Sören; Heyne, Henrike O; Meier, Thomas; Lösch, Sandra; Meller, Harald; Friederich, Susanne; Nicklisch, Nicole; Alt, Kurt W; Schreiber, Stefan; Tholey, Andreas; Herbig, Alexander; Nebel, Almut; Krause, Johannes
2018-05-10
The hepatitis B virus (HBV) is one of the most widespread human pathogens known today, yet its origin and evolutionary history are still unclear and controversial. Here, we report the analysis of three ancient HBV genomes recovered from human skeletons found at three different archaeological sites in Germany. We reconstructed two Neolithic and one medieval HBV genomes by de novo assembly from shotgun DNA sequencing data. Additionally, we observed HBV-specific peptides using paleo-proteomics. Our results show that HBV circulates in the European population for at least 7000 years. The Neolithic HBV genomes show a high genomic similarity to each other. In a phylogenetic network, they do not group with any human-associated HBV genome and are most closely related to those infecting African non-human primates. These ancient virus forms appear to represent distinct lineages that have no close relatives today and possibly went extinct. Our results reveal the great potential of ancient DNA from human skeletons in order to study the long-time evolution of blood borne viruses. © 2018, Krause-Kyora et al.
1958-2008: 50 years of youth fitness tests in the United States.
Morrow, James R; Zhu, Weimo; Franks, B Don; Meredith, Marilu D; Spain, Christine
2009-03-01
The AAHPER Youth Fitness Test, the first U.S. national fitness test, was published 50 years ago. The seminal work of Krause and Hirschland influenced the fitness world and continues to do so today. Important youth fitness test initiatives in the last half century are summarized. Key elements leading to continued interest in youth fitness testing at the start of the 21st century include (a) concerns about children and youth fitness levels, (b) AAHPER(D)-led youth fitness battery development, (c) differentiation between performance-related and health-related fitness testing, (d) the numerous youth fitness tests developed, (e) collaborative discussions on development and adoption of a unified national youth fitness battery, (f) computerization of youth fitness test results, (g) differentiation between norm-referenced and criterion-referenced evaluation of student results, and (h) concern about youth fitness levels (again, but with a focus on health). We have come full circle on youth fitness interests. This article summarizes the key youth fitness tests in the second half of the 20th century and projects future considerations.
2017-12-08
NASA's Fermi Closes on Source of Cosmic Rays New images from NASA's Fermi Gamma-ray Space Telescope show where supernova remnants emit radiation a billion times more energetic than visible light. The images bring astronomers a step closer to understanding the source of some of the universe's most energetic particles -- cosmic rays. This composite shows the Cassiopeia A supernova remnant across the spectrum: Gamma rays (magenta) from NASA's Fermi Gamma-ray Space Telescope; X-rays (blue, green) from NASA's Chandra X-ray Observatory; visible light (yellow) from the Hubble Space Telescope; infrared (red) from NASA's Spitzer Space Telescope; and radio (orange) from the Very Large Array near Socorro, N.M. Credit: NASA/DOE/Fermi LAT Collaboration, CXC/SAO/JPL-Caltech/Steward/O. Krause et al., and NRAO/AUI For more information: www.nasa.gov/mission_pages/GLAST/news/cosmic-rays-source.... NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe. Follow us on Twitter Join us on Facebook
Kraus, Robert H S; van Hooft, Pim; Waldenström, Jonas; Latorre-Margalef, Neus; Ydenberg, Ronald C; Prins, Herbert H T
2011-08-02
Avian Influenza Viruses (AIVs) infect many mammals, including humans(1). These AIVs are diverse in their natural hosts, harboring almost all possible viral subtypes(2). Human pandemics of flu originally stem from AIVs(3). Many fatal human cases during the H5N1 outbreaks in recent years were reported. Lately, a new AIV related strain swept through the human population, causing the 'swine flu epidemic'(4). Although human trading and transportation activity seems to be responsible for the spread of highly pathogenic strains(5), dispersal can also partly be attributed to wild birds(6, 7). However, the actual reservoir of all AIV strains is wild birds. In reaction to this and in face of severe commercial losses in the poultry industry, large surveillance programs have been implemented globally to collect information on the ecology of AIVs, and to install early warning systems to detect certain highly pathogenic strains(8-12). Traditional virological methods require viruses to be intact and cultivated before analysis. This necessitates strict cold chains with deep freezers and heavy biosafety procedures to be in place during transport. Long-term surveillance is therefore usually restricted to a few field stations close to well equipped laboratories. Remote areas cannot be sampled unless logistically cumbersome procedures are implemented. These problems have been recognised(13, 14) and the use of alternative storage and transport strategies investigated (alcohols or guanidine)(15-17). Recently, Kraus et al.(18) introduced a method to collect, store and transport AIV samples, based on a special filter paper. FTA cards(19) preserve RNA on a dry storage basis(20) and render pathogens inactive upon contact(21). This study showed that FTA cards can be used to detect AIV RNA in reverse-transcription PCR and that the resulting cDNA could be sequenced and virus genes and determined. In the study of Kraus et al.(18) a laboratory isolate of AIV was used, and samples were handled individually. In the extension presented here, faecal samples from wild birds from the duck trap at the Ottenby Bird Observatory (SE Sweden) were tested directly to illustrate the usefulness of the methods under field conditions. Catching of ducks and sample collection by cloacal swabs is demonstrated. The current protocol includes up-scaling of the work flow from single tube handling to a 96-well design. Although less sensitive than the traditional methods, the method of FTA cards provides an excellent supplement to large surveillance schemes. It allows collection and analysis of samples from anywhere in the world, without the need to maintaining a cool chain or safety regulations with respect to shipping of hazardous reagents, such as alcohol or guanidine.
DWH MC 252: Subsurface Oil Transport
NASA Astrophysics Data System (ADS)
Beegle-Krause, C. J.; Boyer, T.; Murray, D.
2010-12-01
Before reaching the ocean surface, the oil and gas released from the DWH MC 252 blowout at 1500 m moves as a buoyant plume until the trapping depth and plume transition point are reached (Zheng et al 2002). At the transition point, the oil droplets and bubbles move independently of each other, and rise at a rate related to their diameter. The oil density, droplet size distribution and currents primarily determine the distribution of the oil between: Large droplets that rise quickly and create a surface expression of the oil. Moderate size droplets that rise over the course of days, and so spread out quite differently than the surface oil, and commonly do not reach the surface in large enough quantities to create a surface sheen. These droplets separate in the currents, particularly in the strong current shear in upper 500 m currents. Very tiny droplets that rise very slowly, over the course or weeks to months, and may be removed by dissolution, biodegradation or marine snow before ever reaching the surface. Modeling and observations (Joint Analysis Group, 2010) confirm the presence of a deep layer of oil and gas between approximately 1100 and 1300 m over the release location and spreading out along the isopycnal surfaces. Later in the event, a small oxygen depression was a proxy for where oil and gas had been. The DWH MC252 well is located at intermediate depth in the Gulf of Mexico (GoM). The water mass is Antarctic Intermediate Water, which enters and exits the GoM through the Yucatan Straits. Surface influences, such as Loop Current Frontal Eddies (e.g. Berger et al 2000) can reach down to these depths, and alter the flow within De Soto Canyon. The water mass containing the deep layer of oil droplets changes depth within the GoM, but does not reach above a depth of about 900 m. There are no physical processes that could cause this deep layer of oil to reach the continental shelf or the Florida Straits. Observed and historical hydrographic data, observations, previous research and modeling were combined to tell the story of the DWH MC 252 from the subsurface perspective. The Comprehensive Deepwater Oil and Gas model (CDOG, Yapa and Xie, 2005), and the General NOAA Operational Modeling Environment (GNOME, Beegle-Krause, 1999) were used with the NOAA Gulf of Mexico Model nowcast/forecast model to understand the 3D evolution of the subsurface spill. Model/observational comparisons are favorable, though limitations of the available models are apparent. Historical perspective on Thunder Horse (a deepwater well incident that was a dress-rehearsal for the DWH MC 252, Beegle-Krause and Walton, 2004), transitioning models from research to operations, and research needs will also be discussed.
Mars Exploration Rover Landing Site Hectometer Slopes
NASA Astrophysics Data System (ADS)
Haldemann, A. F.; Anderson, F. S.
2002-12-01
The Mars Exploration Rover (MER) airbag landing system imposes a maximum slope of 5 degrees over 100 m length-scales. This limit avoids dangerous changes in elevation over the horizontal travel distance of the lander on its parachute between the time of the last radar altimeter detection of the surface and the time the retro-rockets fire and the bridle to the airbags is cut. Stereo imagery from the MGS MOC can provide information at this length scale, but MOC stereo coverage is sparse, even when targeted to MER landing sites. Additionally, MGS spacecraft stability issues affect the DEMs at precisely the hectometric length-scale1. The MOLA instrument provides global coverage pulse-width measurements2 over a single MOLA-pulse footprint, which is about 100 m in diameter. However, the pulse spread only provides an upper bound on the 100 m slope. We chose another approach. We sample the inter-pulse root-mean-square (RMS) height deviations for MOLA track segments restricted to pixels of 0.1 deg latitude by 0.1 deg longitude. Then, under the assumption of self-affine topography, we determine the scale-dependence of the RMS deviations and extrapolate that behavior over the range of 300 m to 1.2 km downward to the 100 m scale. Shepard et al.3 clearly summarize the statistical properties of the RMS deviation (noting that it also goes by the name structure function, variogram or Allan deviation), and we follow their nomenclature. The RMS deviation is a useful measure in that it can be directly converted to RMS-slope for a given length-scale. We map the results of this self-affine extrapolation method for each of the proposed MER landing sites as well as Viking Lander 1 (VL1) and Pathfiner (MPF). In order of decreasing average hectometer RMS-slopes, Melas (about 4.5 degrees) > Elysium EP80 > Gusev > MPF > Elysium EP78 > VL1 > Athabasca > Isidis > Hematite (about 1 degree). We also map the scaling parameter (Hurst exponent); its behavior in the MER landing site regions is interesting in how it ties together the regional behavior of kilometer slopes (directly measured with MOLA) with the decameter and meter slopes (locally derived from stereo image analysis or radar scattering). 1Kirk, R. L., E. Howington-Kraus, and B. A. Archinal, Int. Arch. Photogramm. Remote Sens., XXVIII(B4), 476 (CD-ROM), 2001; Kirk, R. L., E. Howington-Kraus, and B. A. Archinal, Lunar Planet Sci., XXXIII, abs 1988, 2002. 2Garvin, J. B., and J. J. Frawley, Lunar Planet. Sci., XXXI, abs 1884, 2000. 3Shepard, M. K., R. A. Brackett, and R. E. Arvidson, J. Geophys. Res., 100, 11709-11718, 1995.; Shepard, M. K., et al., J. Geophys. Res., 106, 32777-32796, 2001.
Kraus, Robert H.S.; van Hooft, Pim; Waldenström, Jonas; Latorre-Margalef, Neus; Ydenberg, Ronald C.; Prins, Herbert H.T.
2011-01-01
Avian Influenza Viruses (AIVs) infect many mammals, including humans1. These AIVs are diverse in their natural hosts, harboring almost all possible viral subtypes2. Human pandemics of flu originally stem from AIVs3. Many fatal human cases during the H5N1 outbreaks in recent years were reported. Lately, a new AIV related strain swept through the human population, causing the 'swine flu epidemic'4. Although human trading and transportation activity seems to be responsible for the spread of highly pathogenic strains5, dispersal can also partly be attributed to wild birds6, 7. However, the actual reservoir of all AIV strains is wild birds. In reaction to this and in face of severe commercial losses in the poultry industry, large surveillance programs have been implemented globally to collect information on the ecology of AIVs, and to install early warning systems to detect certain highly pathogenic strains8-12. Traditional virological methods require viruses to be intact and cultivated before analysis. This necessitates strict cold chains with deep freezers and heavy biosafety procedures to be in place during transport. Long-term surveillance is therefore usually restricted to a few field stations close to well equipped laboratories. Remote areas cannot be sampled unless logistically cumbersome procedures are implemented. These problems have been recognised13, 14 and the use of alternative storage and transport strategies investigated (alcohols or guanidine)15-17. Recently, Kraus et al.18 introduced a method to collect, store and transport AIV samples, based on a special filter paper. FTA cards19 preserve RNA on a dry storage basis20 and render pathogens inactive upon contact21. This study showed that FTA cards can be used to detect AIV RNA in reverse-transcription PCR and that the resulting cDNA could be sequenced and virus genes and determined. In the study of Kraus et al.18 a laboratory isolate of AIV was used, and samples were handled individually. In the extension presented here, faecal samples from wild birds from the duck trap at the Ottenby Bird Observatory (SE Sweden) were tested directly to illustrate the usefulness of the methods under field conditions. Catching of ducks and sample collection by cloacal swabs is demonstrated. The current protocol includes up-scaling of the work flow from single tube handling to a 96-well design. Although less sensitive than the traditional methods, the method of FTA cards provides an excellent supplement to large surveillance schemes. It allows collection and analysis of samples from anywhere in the world, without the need to maintaining a cool chain or safety regulations with respect to shipping of hazardous reagents, such as alcohol or guanidine. PMID:21847074
Performance Comparison of SDN Solutions for Switching Dedicated Long-Haul Connections
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rao, Nageswara S
2016-01-01
We consider scenarios with two sites connected over a dedicated, long-haul connection that must quickly fail-over in response to degradations in host-to-host application performance. We present two methods for path fail-over using OpenFlowenabled switches: (a) a light-weight method that utilizes host scripts to monitor the application performance and dpctl API for switching, and (b) a generic method that uses two OpenDaylight (ODL) controllers and REST interfaces. The restoration dynamics of the application contain significant statistical variations due to the controllers, north interfaces and switches; in addition, the variety of vendor implementations further complicates the choice between different solutions. We presentmore » the impulse-response method to estimate the regressions of performance parameters, which enables a rigorous and objective comparison of different solutions. We describe testing results of the two methods, using TCP throughput and connection rtt as main parameters, over a testbed consisting of HP and Cisco switches connected over longhaul connections emulated in hardware by ANUE devices. The combination of analytical and experimental results demonstrates that dpctl method responds seconds faster than ODL method on average, while both methods restore TCP throughput.« less
The 6dF Galaxy Survey: Mass and Motions in the Local Universe
NASA Astrophysics Data System (ADS)
Colless, M.; Jones, H.; Campbell, L.; Burkey, D.; Taylor, A.; Saunders, W.
2005-01-01
The 6dF Galaxy Survey will provide 167000 redshifts and about 15000 peculiar velocities for galaxies over most of the southern sky out to about cz = 30000 km/s. The survey is currently almost half complete, with the final observations due in mid-2005. An initial data release was made public in December 2002; the first third of the dataset will be released at the end of 2003, with the remaining thirds being released at the end of 2004 and 2005. The status of the survey, the survey database and other relevant information can be obtained from the 6dFGS web site at http://www.mso.anu.edu.au/6dFGS. In terms of constraining cosmological parameters, combining the 6dFGS redshift and peculiar velocity surveys will allow us to: (1) break the degeneracy between the redshift-space distortion parameter beta = Omega_m0.6b/b and the galaxy-mass correlation parameter rg; (2) measure the four parameters Ag, Gamma, beta and rg with precisions of between 1% and 3%; (3) measure the variation of rg and b with scale to within a few percent over a wide range of scales.
Operation of the “Small” BioAMS spectrometers at CAMS: Past and future prospects
Ognibene, T. J.; Haack, K. W.; Bench, G.; ...
2015-05-26
A summary of results from the solid samples run on our compact 1 MV AMS system over its 13.5 years of operation is presented. On average 7065 samples per year were measured with that average dropping to 3278 samples per year following the deployment of our liquid sample capability. Although the dynamic range of our spectrometer is 4.5 orders in magnitude, most of the measured graphitic samples had 14C/C concentrations between 0.1 and 1 modern. Furthermore, the measurements of our ANU sucrose standard followed a Gaussian distribution with an average of 1.5082 ± 0.0134 modern. The LLNL biomedical AMS programmore » supported many different types of experiments, however, the large majority of samples measured were derived from animal model systems. We have transitioned all of our biomedical AMS measurements to the recently installed 250 kV SSAMS instrument with good agreement compared in measured 14C/C isotopic ratios between sample splits. We then present results from replacement of argon stripping gas with helium in the SSAMS with a 22% improvement in ion transmission through the accelerator and high-energy analyzing magnet.« less
Operation of the “Small” BioAMS Spectrometers at CAMS: Past and Future Prospects
Ognibene, T.J.; Haack, K.W.; Bench, G.; Brown, T.A.; Turteltaub, K.W.
2015-01-01
A summary of results from the solid samples run on our compact 1 MV AMS system over its 13.5 years of operation is presented. On average 7065 samples per year were measured with that average dropping to 3278 samples per year following the deployment of our liquid sample capability. Although the dynamic range of our spectrometer is 4.5 orders in magnitude, most of the measured graphitic samples had 14C/C concentrations between 0.1 and 1 modern. The measurements of our ANU sucrose standard followed a Gaussian distribution with an average of 1.5082 ± 0.0134 modern. The LLNL biomedical AMS program supported many different types of experiments, however, the large majority of samples measured were derived from animal model systems. We have transitioned all of our biomedical AMS measurements to the recently installed 250 kV SSAMS instrument with good agreement compared in measured 14C/C isotopic ratios between sample splits. Finally, we present results from replacement of argon stripping gas with helium in the SSAMS with a 22% improvement in ion transmission through the accelerator and high-energy analyzing magnet. PMID:26456990
Continuous Opinion Dynamics Under Bounded Confidence:. a Survey
NASA Astrophysics Data System (ADS)
Lorenz, Jan
Models of continuous opinion dynamics under bounded confidence have been presented independently by Krause and Hegselmann and by Deffuant et al. in 2000. They have raised a fair amount of attention in the communities of social simulation, sociophysics and complexity science. The researchers working on it come from disciplines such as physics, mathematics, computer science, social psychology and philosophy. In these models agents hold continuous opinions which they can gradually adjust if they hear the opinions of others. The idea of bounded confidence is that agents only interact if they are close in opinion to each other. Usually, the models are analyzed with agent-based simulations in a Monte Carlo style, but they can also be reformulated on the agent's density in the opinion space in a master equation style. The contribution of this survey is fourfold. First, it will present the agent-based and density-based modeling frameworks including the cases of multidimensional opinions and heterogeneous bounds of confidence. Second, it will give the bifurcation diagrams of cluster configuration in the homogeneous model with uniformly distributed initial opinions. Third, it will review the several extensions and the evolving phenomena which have been studied so far, and fourth it will state some open questions.
Groundbreaking for the NACA’s Aircraft Engine Research Laboratory
1941-01-21
Local politicians and National Advisory Committee for Aeronautics (NACA) officials were on hand for the January 23, 1941 groundbreaking for the NACA’s Aircraft Engine Research Laboratory (AERL). The NACA was established in 1915 to coordinate the nation’s aeronautical research. The committee opened a research laboratory at Langley Field in 1920. By the late 1930s, however, European nations, Germany in particular, were building faster and higher flying aircraft. The NACA decided to expand with a new Ames Aeronautical Laboratory dedicated to high-speed flight and the AERL to handle engine-related research. The NACA examined a number of Midwest locations for its new engine lab before deciding on Cleveland. At the time, Cleveland possessed the nation’s most advanced airport, several key aircraft manufacturing companies, and was home to the National Air Races. Local officials were also able to broker a deal with the power company to discount its electricity rates if the large wind tunnels were operated overnight. The decision was made in October 1940, and the groundbreaking alongside the airport took place on January 23, 1941. From left to right: William Hopkins, John Berry, Ray Sharp, Frederick Crawford, George Brett, Edward Warner, Sydney Kraus, Edward Blythin, and George Lewis
NASA Astrophysics Data System (ADS)
Baltz, Anthony J.
2002-10-01
Theoretical predictions for a number of electromagnetically induced reactions have been compared with available ultrarelativistic heavy ion data. Calculations for three atomic process have been confronted with CERN SPS data. Theoretically predicted rates are in good agreement with data[1] for bound-electron positron pairs and ionization of single electron heavy ions. Furthermore, the exact solution of the semi-classical Dirac equation in the ultrarelativistic limit reproduces the perturbative scaling result seen in data[2] for continuum pairs (i.e. cross sections go as Z_1^2 Z_2^2). In the area of electromagnetically induced nuclear and hadronic physics, mutual Coulomb dissociation predictions are in good agreement with RHIC Zero Degree Calorimeter measurements[3], and calculations of coherent vector meson production accompanied by mutual Coulomb dissociation[4] are in good agreement with RHIC STAR data[5]. [1] H. F. Krause et al., Phys. Rev. Lett., 80, 1190 (1998). [2] C. R. Vane et al., Phys. Rev. A 56, 3682 (1997). [3] Mickey Chiu et al., Phys. Rev. Lett. 89, 012302 (2002). [4] Anthony J. Baltz, Spencer R. Klein, and Joakim Nystrand, Phys. Rev. Lett. 89, 012301 (2002). [5] C. Adler et al., STAR Collaboration, arXiv:nucl-ex/206004.
Efficient universal quantum channel simulation in IBM's cloud quantum computer
NASA Astrophysics Data System (ADS)
Wei, Shi-Jie; Xin, Tao; Long, Gui-Lu
2018-07-01
The study of quantum channels is an important field and promises a wide range of applications, because any physical process can be represented as a quantum channel that transforms an initial state into a final state. Inspired by the method of performing non-unitary operators by the linear combination of unitary operations, we proposed a quantum algorithm for the simulation of the universal single-qubit channel, described by a convex combination of "quasi-extreme" channels corresponding to four Kraus operators, and is scalable to arbitrary higher dimension. We demonstrated the whole algorithm experimentally using the universal IBM cloud-based quantum computer and studied the properties of different qubit quantum channels. We illustrated the quantum capacity of the general qubit quantum channels, which quantifies the amount of quantum information that can be protected. The behavior of quantum capacity in different channels revealed which types of noise processes can support information transmission, and which types are too destructive to protect information. There was a general agreement between the theoretical predictions and the experiments, which strongly supports our method. By realizing the arbitrary qubit channel, this work provides a universally- accepted way to explore various properties of quantum channels and novel prospect for quantum communication.
Leader's opinion priority bounded confidence model for network opinion evolution
NASA Astrophysics Data System (ADS)
Zhu, Meixia; Xie, Guangqiang
2017-08-01
Aiming at the weight of trust someone given to participate in the interaction in Hegselmann-Krause's type consensus model is the same and virtual social networks among individuals with different level of education, personal influence, etc. For differences between agents, a novelty bounded confidence model was proposed with leader's opinion considered priority. Interaction neighbors can be divided into two kinds. The first kind is made up of "opinion leaders" group, another kind is made up of ordinary people. For different groups to give different weights of trust. We also analyzed the related characteristics of the new model under the symmetrical bounded confidence parameters and combined with the classical HK model were analyzed. Simulation experiment results show that no matter the network size and initial view is subject to uniform distribution or discrete distribution. We can control the "opinion-leader" good change the number of views and values, and even improve the convergence speed. Experiment also found that the choice of "opinion leaders" is not the more the better, the model well explain how the "opinion leader" in the process of the evolution of the public opinion play the role of the leader.
Effects of fixture rotation on coating uniformity for high-performance optical filter fabrication
NASA Astrophysics Data System (ADS)
Rubin, Binyamin; George, Jason; Singhal, Riju
2018-04-01
Coating uniformity is critical in fabricating high-performance optical filters by various vacuum deposition methods. Simple and planetary rotation systems with shadow masks are used to achieve the required uniformity [J. B. Oliver and D. Talbot, Appl. Optics 45, 13, 3097 (2006); O. Lyngnes, K. Kraus, A. Ode and T. Erguder, in `Method for Designing Coating Thickness Uniformity Shadow Masks for Deposition Systems with a Planetary Fixture', 2014 Technical Conference Proceedings, Optical Coatings, August 13, 2014, DOI: 10.14332/svc14.proc.1817.]. In this work, we discuss the effect of rotation pattern and speed on thickness uniformity in an ion beam sputter deposition system. Numerical modeling is used to determine statistical distribution of random thickness errors in coating layers. The relationship between thickness tolerance and production yield are simulated theoretically and demonstrated experimentally. Production yields for different optical filters produced in an ion beam deposition system with planetary rotation are presented. Single-wavelength and broadband optical monitoring systems were used for endpoint monitoring during filter deposition. Limitations of thickness tolerances that can be achieved in systems with planetary rotation are shown. Paths for improving production yield in an ion beam deposition system are described.
Synthetic Survey of the Kepler Field
NASA Astrophysics Data System (ADS)
Wells, Mark; Prša, Andrej
2018-01-01
In the era of large scale surveys, including LSST and Gaia, binary population studies will flourish due to the large influx of data. In addition to probing binary populations as a function of galactic latitude, under-sampled groups such as low mass binaries will be observed at an unprecedented rate. To prepare for these missions, binary population simulations need to be carried out at high fidelity. These simulations will enable the creation of simulated data and, through comparison with real data, will allow the underlying binary parameter distributions to be explored. In order for the simulations to be considered robust, they should reproduce observed distributions accurately. To this end we have developed a simulator which takes input models and creates a synthetic population of eclipsing binaries. Starting from a galactic single star model, implemented using Galaxia, a code by Sharma et al. (2011), and applying observed multiplicity, mass-ratio, period, and eccentricity distributions, as reported by Raghavan et al. (2010), Duchêne & Kraus (2013), and Moe & Di Stefano (2017), we are able to generate synthetic binary surveys that correspond to any survey cadences. In order to calibrate our input models we compare the results of our synthesized eclipsing binary survey to the Kepler Eclipsing Binary catalog.
Mass Mapping Abell 2261 with Kinematic Weak Lensing: A Pilot Study for NASAs WFIRST mission
NASA Astrophysics Data System (ADS)
Eifler, Tim
2015-02-01
We propose to investigate a new method to extract cosmological information from weak gravitational lensing in the context of the mission design and requirements of NASAs Wide-Field Infrared Survey Telescope (WFIRST). In a recent paper (Huff, Krause, Eifler, George, Schlegel 2013) we describe a new method for reducing the shape noise in weak lensing measurements by an order of magnitude. Our method relies on spectroscopic measurements of disk galaxy rotation and makes use of the well-established Tully-Fisher (TF) relation in order to control for the intrinsic orientations of galaxy disks. Whereas shape noise is one of the major limitations for current weak lensing experiments it ceases to be an important source of statistical error in our new proposed technique. Specifically, we propose a pilot study that maps the projected mass distribution in the massive cluster Abell 2261 (z=0.225) to infer whether this promising technique faces systematics that prohibit its application to WFIRST. In addition to the cosmological weak lensing prospects, these measurements will also allow us to test kinematic lensing in the context of cluster mass reconstruction with a drastically improved signal-to-noise (S/N) per galaxy.
NASA Astrophysics Data System (ADS)
Segler, Kurt; Williams, W.; Siegel, E.
2010-03-01
Detailed are old blowpipe[Kraus,Hunt,Ramsdell, Mineralogy (1936)] new applications:charcoal-block reduction of borates to yield (``N-NW'' of MgB2) Overhauser-[PR 35,1,411(1987); Intl.J.Mod.Phys.1,2 & 4,927(1987)]-``land'' predicted high-EST- POSSIBLE Tc SC ˜ ``LiD2''; very-early: Siegel[Phys.Stat.Sol.(a) 11,45(1972);Semiconductors & Insulators 5: 39,47,62(1979)] carb- IDES SOLID-state phase-TRANSITIONED CHEMICALLY-REDOX"-REACTED STABLE PERMANENT LONG-term STRATEGY, NOT ``CO2" BUT NON-gas Carbon-``ELEMENT"-sequestration: PROFITABLE MARKETABLE SALEABLE VALUABLE USEFUL ``Grab and Sell" TRUMPS ``cap and trade"!!!; Mott alloying/vertical metal-insulator transitions in ``borax-(GLASS)- beads"; and very-early Siegel [3rd Intl.Conf.Alt.Energy,Hemi- sphere/Springer(1980)-vol.5/p.459] ``FLYING-WATER" ``Hindenberg- effect"(H2-UP;H2O-DOWN) via H2-maximal-Archimedes-buoyancy ``chemical-rain-in-piplines", only via Siegel GMR enabled diffusive-magnetoresistance(DMR)enabled Siegel proprietary ``magnetic-H-valve": Renewables-H2-H2O purposely flexible versatile agile scaleable retrofitable integrated operating- system for PERMANENT drought(s)-elimination FOREVER!!!
NASA Astrophysics Data System (ADS)
Chauhan, Yogeshwar; Tiwari, M. K.; Puri, Sanjiv
2008-01-01
The L k ( k = l, α, β 1,4, β 3,6, β 2,15,9,10,7, γ 1,5 and γ 2,3,4) X-ray production (XRP) cross sections have been measured for six elements with 56 ⩽ Z ⩽ 68 at 22.6 keV incident photon energy using the EDXRF spectrometer. The incident photon intensity, detector efficiency and geometrical factors have been determined from the K X-ray yields emitted from elemental targets with 22 ⩽ Z ⩽ 42 in the same geometrical setup and from knowledge of the K XRP cross sections. The L 1 and L 2 subshell fluorescence yields have been deduced from the present measured L k XRP cross sections using the relativistic Hartree-Fock-Slater (HFS) model based photoionization cross sections. The present deduced ω1 (exp) values have been found to be, on an average, higher by 15% and 20% than those based on the Dirac-Hartree-Slater (DHS) model and the semi-empirical values compiled by Krause, respectively, for elements with 60 ⩽ Z ⩽ 68.
Invasive reptiles and amphibians: global perspectives and local solutions
Reed, R.N.; Kraus, F.
2010-01-01
In the annals of invasive species biology, higher taxa such asmammals, plants and insects have received the lion’s shareof research attention, largely because many of these invadershave demonstrated a remarkable ability to degrade ecosys-tems and cause economic harm. Interest in invasive reptilesand amphibians (collectively ‘herpetofauna’, colloquially‘herps’) has historically lagged but is now garnering in-creased scrutiny as a result of their escalating pace ofinvasion. A few herpetofaunal invaders have received con-siderable attention in scientific and popular accounts, in-cluding the brown treesnakeBoiga irregularison Guam,Burmese pythonPython molurusin Florida, Coqu´ıEleutherodactylus coquiin Hawaii and cane toadBufomarinusin Australia. However, relatively few are aware ofmany emerging and potentially injurious herpetofaunalinvaders, such as Nile monitorsVaranus niloticusin Flor-ida, common kingsnakesLampropeltis getulain the CanaryIslands, boa constrictorsBoa constrictoron Aruba andCozumel, or a variety of giant constrictor snakes in PuertoRico. For the vast majority of the most commonlyintroduced species, real or potential impacts to nativeecosystems or human economic interests are poorly under-stood and incompletely explored; major pathways of intro-duction have only recently been elucidated, and effectivemanagement interventions have been limited (Kraus, 2009).
NASA Astrophysics Data System (ADS)
Barmina, I.; Līckrastiņa, A.; Valdmanis, J.; Valdmanis, R.; Zaķe, M.; Arshanitsa, A.; Telysheva, G.; Solodovnik, V.
2013-08-01
To effectively produce clean heat energy from biomass, microwave (mw) pre-processing of its different types - pelletized wood (spruce), herbaceous biomass (reed canary grass) and their mixture (50:50) - was carried out at the 2.45 GHz frequency with different durations of biomass exposure to high-frequency oscillations. To estimate the mw pre-processing effect on the structure, composition and fuel characteristics of biomass, its thermogravimetric (TG), infrared spectroscopy (FTIR) measurements and elemental analysis were made. The pre-processing is shown to enhance the release of moisture and low-calorific volatiles and the partial destruction of biomass constituents (hemicelluloses, cellulose), promoting variations in the elemental composition and heating values of biomass. The field-enhanced variations of biomass characteristics and their influence on its gasification and combustion were studied using an integrated system of a biomass gasifier and a combustor with swirl-enhanced stabilization of the flame reaction zone. The results show that the mw pre-processing of biomass pellets provides a faster weight loss at the gasification, and, therefore, faster ignition and combustion of the activated pellets along with increased output of heat energy at their burnout Veikti kompleksi eksperimentālie pētījumi par mikroviļņu (2,45 GHz) priekšapstrādes ietekmi uz dažādas izcelsmes biomasas granulu (egles, miežabrāļa un to maisījumu 50:50) gazifikācijas un degšanas procesiem. Pētījumi apvieno granulētās biomasas elementārā sastāva un termogravimetriskos mērījumus, kā arī granulētās biomasas gazifikācijas un degšanas procesu kompleksu izpēti, apvienojot biomasas svara izmaiņu kinētiskos mērījumus ar degšanas zonas temperatūras, iekārtas jaudas un degšanas produktu sastāva kinētiskiem mērījumiem. Pētījumiem izmantota mazas jaudas eksperimentālā iekārta (līdz 2,5 kW), kuru veido integrēts gazifikātors un degšanas kamera. Pētījumu rezultātā konstatēts, ka mikroviļņu priekšapstrāde nodrošina intensīvāku biomasas gazifikāciju, ātrāku gaistošo savienojumu veidošanos, uzliesmošanu un pilnīgāku sadedzināšanu ar sekojošu saražotās īpatnējā siltuma enerģijas pieaugumu
NASA Astrophysics Data System (ADS)
Nakada, Masao; Okuno, Jun'ichi; Lambeck, Kurt; Purcell, Anthony
2015-08-01
We examine the geodetically derived rotational variations for the rate of change of degree-two harmonics of Earth's geopotential, skew5dot J_2, and true polar wander, combining a recent melting model of glaciers and the Greenland and Antarctic ice sheets taken from the IPCC 2013 Report (AR5) with two representative GIA ice models describing the last deglaciation, ICE5G and the ANU model developed at the Australian National University. Geodetically derived observations of skew4dot J_2 are characterized by temporal changes of -(3.7 ± 0.1) × 10-11 yr-1 for the period 1976-1990 and -(0.3 ± 0.1) × 10-11 yr-1 after ˜2000. The AR5 results make it possible to evaluate the recent melting of the major ice sheets and glaciers for three periods, 1900-1990, 1991-2001 and after 2002. The observed skew4dot J_2 and the component of skew4dot J_2 due to recent melting for different periods indicate a long-term change in skew4dot J_2-attributed to the Earth's response to the last glacial cycle-of -(6.0-6.5) × 10-11 yr-1, significantly different from the values adopted to infer the viscosity structure of the mantle in most previous studies. This is a main conclusion of this study. We next compare this estimate with the values of skew4dot J_2 predicted by GIA ice models to infer the viscosity structure of the mantle, and consequently obtain two permissible solutions for the lower mantle viscosity (ηlm), ˜1022 and (5-10) × 1022 Pa s, for both adopted ice models. These two solutions are largely insensitive to the lithospheric thickness and upper mantle viscosity as indicated by previous studies and relatively insensitive to the viscosity structure of the D″ layer. The ESL contributions from the Antarctic ice sheet since the last glacial maximum (LGM) for ICE5G and ANU are about 20 and 30 m, respectively, but glaciological reconstructions of the Antarctic LGM ice sheet have suggested that its ESL contribution may have been less than ˜10 m. The GIA-induced skew4dot J_2 for GIA ice models with an Antarctic ESL component of ˜10 m suggests two permissible lower mantle viscosity solutions of ηlm ˜ 2 × 1022 and ˜5 × 1022 Pa s or one solution with (2-5) × 1022 Pa s. These results suggest that the effective lower mantle viscosity is larger than ˜1022 Pa s regardless of the uncertainties for an Antarctic ESL component. We also examine the polar wander due to recent melting and GIA processes, suggesting that the observed polar wander may be significantly attributed to convection motions in the mantle and/or another cause, particularly for permissible lower mantle viscosity solution of (5-10) × 1022 Pa s.
Bergamaschi, Brian A.; Downing, Bryan D.; Kraus, Tamara E.C.; Pellerin, Brian A.
2017-07-11
Executive SummaryThis report is the third in a series of three reports that provide information about how high-frequency (HF) nutrient monitoring may be used to assess nutrient inputs and dynamics in the Sacramento–San Joaquin Delta, California (Delta). The purpose of this report is to provide the background, principles, and considerations for designing an HF nutrient-monitoring network for the Delta to address high-priority, nutrient-management questions. The report starts with discussion of the high-priority management questions to be addressed, continues through discussion of the questions and considerations that place demands and constraints on network design, discusses the principles applicable to network design, and concludes with the presentation of three example nutrient-monitoring network designs for the Delta. For three example network designs, we assess how they would address high-priority questions that have been identified by the Delta Regional Monitoring Program (Delta Regional Monitoring Program Technical Advisory Committee, 2015).This report, along with the other two reports of this series (Kraus and others, 2017; Downing and others, 2017), was drafted in cooperation with the Delta Regional Monitoring Program to help scientists, managers, and planners understand how HF data improve our understanding of nutrient sources and sinks, drivers, and effects in the Delta. The first report in the series (Kraus and others, 2017) provides an introduction to the reasons for and fundamental concepts behind using HF monitoring measurements, including a brief summary of nutrient status and trends in the Delta and an extensive literature review showing how and where other research and monitoring programs have used HF monitoring to improve our understanding of nutrient cycling. The report covers the various technologies available for HF nutrient monitoring and presents the different ways HF monitoring instrumentation may be used for both fixed station and spatial assessments. Finally, it presents numerous examples of how HF measurements are currently (2017) being used in the Delta to examine how nutrients and nutrient cycling are related to aquatic habitat conditions.The second report in the series (Downing and others, 2017) summarizes information about HF nutrient and associated biogeochemical monitoring in the north Delta. The report synthesizes data available from the nutrient and water quality monitoring network currently (2017) operated by the U.S. Geological Survey in this ecologically important region of the Delta. In the report, we present and discuss the available data at various timescales—first at the monthly, seasonal, and inter-annual timescales; and, second, for comparison, at the tidal and event timescales. As expected, we determined that there is substantial variability in nitrate concentrations at short timescales, such as within a few hours, but also significant variability at longer timescales such as months or years. This high variability affects calculation of fluxes and loads, indicating that HF monitoring is necessary for understanding and assessing flux-based processes and outcomes in Delta tidal environments.
NASA Technical Reports Server (NTRS)
Lambert, Winifred C.; Merceret, Francis J. (Technical Monitor)
2002-01-01
This report describes the results of the ANU's (Applied Meteorology Unit) Short-Range Statistical Forecasting task for peak winds. The peak wind speeds are an important forecast element for the Space Shuttle and Expendable Launch Vehicle programs. The Keith Weather Squadron and the Spaceflight Meteorology Group indicate that peak winds are challenging to forecast. The Applied Meteorology Unit was tasked to develop tools that aid in short-range forecasts of peak winds at tower sites of operational interest. A 7 year record of wind tower data was used in the analysis. Hourly and directional climatologies by tower and month were developed to determine the seasonal behavior of the average and peak winds. In all climatologies, the average and peak wind speeds were highly variable in time. This indicated that the development of a peak wind forecasting tool would be difficult. Probability density functions (PDF) of peak wind speed were calculated to determine the distribution of peak speed with average speed. These provide forecasters with a means of determining the probability of meeting or exceeding a certain peak wind given an observed or forecast average speed. The climatologies and PDFs provide tools with which to make peak wind forecasts that are critical to safe operations.
The 6dF Galaxy Survey: First Data Release
NASA Astrophysics Data System (ADS)
Jones, H.; Saunders, W.; Colless, M.; Read, M.; Parker, Q.; Watson, F.; Campbell, L.
2005-06-01
The 6dF Galaxy Survey (6dFGS) is currently measuring the redshifts of around 170 000 galaxies and the peculiar velocities of a 15 000-member sub-sample. It will be the largest redshift survey of the local universe and more than an order of magnitude larger than any peculiar velocity survey to date. When complete, it will cover essentially the entire southern sky around a mean redshift of z = 0.05. Central to the survey is the Six-Degree Field (6dF) multi-fibre spectrograph, an instrument able to record 150 simultaneous spectra over the 5.7°-field of the UK Schmidt Telescope. Targets have been drawn from the 2MASS Extended Source Catalog (XSC) to include all galaxies brighter than Ktot = 12.75, supplemented by 2MASS and SuperCOSMOS galaxies that complete the sample to limits of (H, J, rF, bJ) = (13.05, 13.75, 15.6, 16.75). Here we describe the implementation of the survey and the procedures used to select sources and determine redshifts. We also describe early results utilising the First Data Release of ˜ 45 000 redshifts. There is an online database of 6dFGS data accessible from the 6dFGS web site (http://www.mso.anu.edu.au/6dFGS).
NASA Astrophysics Data System (ADS)
Seitenzahl, Ivo R.; Vogt, Frédéric P. A.; Terry, Jason P.; Ghavamian, Parviz; Dopita, Michael A.; Ruiter, Ashley J.; Sukhbold, Tuguldur
2018-02-01
We study the optical emission from heavy element ejecta in the oxygen-rich young supernova remnant 1E 0102.2–7219 (1E 0102) in the Small Magellanic Cloud. We have used the Multi-Unit Spectroscopic Explorer optical integral field spectrograph at the Very Large Telescope on Cerro Paranal and the wide field spectrograph (WiFeS) at the ANU 2.3 m telescope at Siding Spring Observatory to obtain deep observations of 1E 0102. Our observations cover the entire extent of the remnant from below 3500 Å to 9350 Å. Our observations unambiguously reveal the presence of fast-moving ejecta emitting in [S II], [S III], [Ar III], and [Cl II]. The sulfur-rich ejecta appear more asymmetrically distributed compared to oxygen or neon, a product of carbon burning. In addition to the forbidden line emission from products of oxygen burning (S, Ar, Cl), we have also discovered Hα and Hβ emission from several knots of low surface brightness, fast-moving ejecta. The presence of fast-moving hydrogen points toward a progenitor that had not entirely shed its hydrogen envelope prior to the supernova. The explosion that gave rise to 1E 0102 is therefore commensurate with a Type IIb supernova.
Time Reversed Electromagnetics as a Novel Method for Wireless Power Transfer
NASA Astrophysics Data System (ADS)
Challa, Anu; Anlage, Steven M.; Tesla Team
Taking advantage of ray-chaotic enclosures, time reversal has been shown to securely transmit information via short-wavelength waves between two points, yielding noise at all other sites. In this presentation, we propose a method to adapt the signal-focusing technique to electromagnetic signals in order to transmit energy to portable devices. Relying only on the time-reversal invariance properties of waves, the technique is unencumbered by the inversely-proportional-to-distance path loss or precise orientation requirements of its predecessors, making it attractive for power transfer applications. We inject a short microwave pulse into a complex, wave-chaotic chamber and collect the resulting long time-domain signal at a designated transceiver. The signal is then time reversed and emitted from the collection site, collapsing as a time-reversed replica of the initial pulse at the injection site. When amplified, this reconstruction is robust, as measured through metrics of peak-to-peak voltage and energy transfer ratio. We experimentally demonstrate that time reversed collapse can be made on a moving target, and propose a way to selectively target devices through nonlinear time-reversal. University of Maryland Gemstone Team TESLA: Frank Cangialosi, Anu Challa, Tim Furman, Tyler Grover, Patrick Healey, Ben Philip, Brett Potter, Scott Roman, Andrew Simon, Liangcheng Tao, Alex Tabatabai.
Identification of an entomopathogenic bacterium, Serratia sp. ANU101, and its hemolytic activity.
Kim, Yonggyun; Kim, Keunseob; Seo, Jiae; Shrestha, Sony; Kim, Hosanna H; Nalini, Madanagopal; Yi, Youngkeun
2009-03-01
Four different bacterial colonies were isolated from an old stock of an entomopathogenic nematode, Steinernema monticolum. They all showed entomopathogenicity to final instar larvae of beet armyworm, Spodoptera exigua, by hemocoelic injection. However, they varied in colony form, susceptibility to antibiotics, and postmortem change of the infected host insects. Biolog microbial identification and 16S rDNA sequence analyses indicate that these are four different species classified into different bacterial genera. owing to high entomopathogenicity and a cadaver color of infected insect host, Serratia sp. was selected as a main symbiotic bacterial species and analyzed for its pathogenicity. Although no virulence of Serratia sp. was detected at oral administration, the bacteria gave significant synergistic pathogenicity to fifth instar S. exigua when it was treated along with a spore-forming entomopathogenic bacterium, Bacillus thuringiensis. The synergistic effect was explained by an immunosuppressive effect of Serratia sp. by its high cytotoxic effect on hemocytes of S. exigua, because Serratia sp. caused septicemia of S. exigua when the bacterial cells were injected into S. exigua hemocoel. The cytotoxic factor(s) was present in the culture medium because the sterilized culture broth possessed high potency in the cytotoxicity, which was specific to granular cells and plasmatocytes, two main immune-associated hemocytes in insects.
Electron impact excitation of NeIII intercombination lines
NASA Astrophysics Data System (ADS)
Daw, Adrian; McLaughlin, Brendan M.; Bell, Kenneth L.
2000-06-01
Observations on the spectra of doubly ionized neon (NeIII) have been recently recorded below 25O Å(A. E. Livington, R. Buttner, A. S. Zacarias, B. Kraus, K-H Schartner, F. Folkmann and P. H. Mokler, J. Opt. Soc. Am. B 14) 522-525 (1997).. This work together with previous studies give line intensies which may be used as density diagnostics but required accurate collision strengths and transition probabilities for their interpretation. Recent studies on electron collisions with NeIII ions using the R-matrix approach (B. M. McLaughlin and K. L. Bell, J. Phys. B. 33), 597 (2000). for Δ n=0 transitions, illustrated the importance of including n=3 and 4 levels in the calculations compared to previous work. (K. Butler and C. Mendoza, Mon. Not. R. Astr. Soc. 208), 17 (1984). Particular emphasis is now placed on transitions to the intercombination 2s^22p^3[^4S^o]3s ^3,5S^o levels and to the other n=3 levels where comparison can be made with previous distorted-wave work. The calculations of fine-structure transitions by electron impact, to and within these multiplets of NeIII provide much needed accurate data for astrophysical models. Further details and a comprehensive set of results will be presented at the meeting.
[President J. H. Brand and his medical history].
Retief, F P
1981-03-14
During his term of office of 25 years (1863-1888) Johannes Hendrikus Brand, fourth President of the Orange Free State, proved himself a remarkable statesman of international stature. Born in the Cape Town of Lord Charles Somerset he was educated in the British tradition, and later received knighthoods from both Portugal and Britain. However, in converting his young embryonic state into South Africa's 'Model Republic' he showed himself to be a staunch republican. Total loyalty towards his country of adoption was aptly demonstrated by his uncompromising stand over the British annexation of the diamond fields in 1871. While preparing to put his case before the Colonial Secretary in London, he developed Bright's disease at the age of 49 years in August 1872. After an extreme illness lasting 5 months he appeared to recover fully. His subsequent health was excellent up to the end of the next decade when he developed symptoms of heart failure, epistaxis and possibly a cerebrovascular incident. In March 1888 his two Bloemfontein doctors, C. J. G. Krause and B. O. Kellner, in consultation with Dr Leander Starr Jameson (of Jameson Raid fame) diagnosed a recurrence of his kidney ailment and progressive heart disease. His death on 14 July 1888 was probably due to acute left ventricular failure as a late hypertensive complication of glomerulonephritis.
Patients' webs of relations in the medical landscapes of Central Ukraine.
Kołodziejska-Degórska, Iwona
2016-08-01
Village dwellers in Central Ukraine have access to various types of therapy that comprise diverse medical landscapes. Patients' movements within these landscapes are possible thanks to each person's web of relations. Medical landscapes are not fixed, but vary and dynamically change for each person, depending on their fluid and interchanging, hierarchical webs of mutual relations with other people, personal bodies, institutions, discourses, political powers, other non-human organisms, or objects such as medicines. This paper was inspired by the medicoscape concept (Hörbst and Krause 2004 ) as well as Ingold's idea of meshwork analyses of relations between various actors: in this case, patients, healers, a weak state, official healthcare providers, pharmacists and medicinal plants, in the context of patients' therapeutic choices. Self-medication based on herbal remedies is a very important feature of people's medical landscapes in Central Ukraine and usually the first therapy choice for most interlocutors. That is why this paper is focused on the presentation of the means through which people acquire knowledge about medicinal plants, and the ways they interact with plants and plants interact with them. In this way, showing the complexity of villagers' webs of relations is possible. The analysis is based on ethnographic research conducted between 2009 and 2013 in the Vinnytsia region (Central Ukraine).
Numerical experiments with a wind- and buoyancy-driven two-and-a-half-layer upper ocean model
NASA Astrophysics Data System (ADS)
Cherniawsky, J. Y.; Yuen, C. W.; Lin, C. A.; Mysak, L. A.
1990-09-01
We describe numerical experiments with a limited domain (15°-67°N, 65° west to east) coarse-resolution two-and-a-half-layer upper ocean model. The model consists of two active variable density layers: a Niiler and Kraus (1977) type mixed layer and a pycnocline layer, which overlays a semipassive deep ocean. The mixed layer is forced with a cosine wind stress and Haney type heat and precipitation-evaporation fluxes, which were derived from zonally averaged climatological (Levitus, 1982) surface temperatures and salinities for the North Atlantic. The second layer is forced from below with (1) Newtonian cooling to climatological temperatures and salinities at the lower boundary, (2) convective adjustment, which occurs whenever the density of the second layer is unstable with respect to climatology, and (3) mass entrainment in areas of strong upwelling, when the deep ocean ventilates through the bottom surface. The sensitivity of this model to changes in its internal (mixed layer) and external (e.g., a Newtonian coupling coefficient) parameters is investigated and compared to the results from a control experiment. We find that the model is not overly sensitive to changes in most of the parameters that were tested, albeit these results may depend to some extent on the choice of the control experiment.
Hoarding behavior among young children with obsessive-compulsive disorder.
Frank, Hannah; Stewart, Elyse; Walther, Michael; Benito, Kristen; Freeman, Jennifer; Conelea, Christ; Garci, Abbe
2014-01-01
Previous research has shown that among the various subtypes of obsessive-compulsive disorder (OCD), adults (e.g. Frost, Krause & Steketee, 1996) and older children and adolescents (Bloch et al., 2009; Storch et al., 2007) with problematic hoarding have distinct features and a poor treatment prognosis. However, there is limited information on the phenomenology and prevalence of hoarding behaviors in young children. The present study characterizes children ages 10 and under who present with OCD and hoarding behaviors. Sixty-eight children received a structured interview-determined diagnosis of OCD. Clinician administered, parent-report, and child-report measures on demographic, symptomatic, and diagnostic variables were completed. Clinician ratings of hoarding symptoms and parent and child endorsement of the hoarding item on the CY-BOCS checklist (Scahill, Riddle, McSwiggin-Hardin, & Ort, 1997) determined inclusion in the hoarding group ( n =33). Compared to children without hoarding symptoms ( n =35), the presence of hoarding symptoms was associated with an earlier age of primary diagnosis onset and a higher proportion of ADHD and provisional anxiety diagnoses. These results are partially consistent with the adult literature and with findings in older children (Storch et al., 2007). Additional data on clinical presentation and phenomenology of hoarding are needed to form a developmentally appropriate definition of the behavior.
M, Bindu; G, Unnikrishnan
2017-09-27
We report the transport characteristics of silicone rubber/nano-hydroxylapatite (SR/n-HA) systems at room temperature with reference to the effects of n-HA loading, morphology and penetrant nature, using toluene, xylene, ethyl acetate and butyl acetate in the liquid phase and methanol, ethanol, 1-propanol, 2-propanol and butanol in the vapour phase as probe molecules. The interaction between the n-HA particles and SR matrix has been confirmed by FTIR analysis. As the n-HA content in the SR matrix increased, the penetrant uptake has been found to decrease. The observations have been correlated with the density and void content of the systems. Scanning electron microscopy images have been found to be complementary to the observed transport features. The reinforcement effect of n-HA particles on the SR matrix has been verified by Kraus equation. Molecular mass between the cross links has been observed to decrease with an increase in n-HA loading. The results have been compared with affine, phantom network, parallel, series and Maxwell models. The transport data have been complemented by observations on biological fluid uptake with urea, d-glucose, KI, saline water, phosphate buffer and artificial urine as the media.
Yoga Practice Increases Minimum Muscular Fitness in Children with Visual Impairment.
Mohanty, Soubhagyalaxmi; Venkata Ramana Murty, Peri; Pradhan, Balaram; Hankey, Alex
2015-12-01
Muscle strength, a component for balance, gait and functional mobility is vital for children with visual impairment. Yoga has frequently been demonstrated to improve physical and mental fitness in children. This study aimed to assess the effect of 16 weeks yoga training on muscular fitness in children with visual impairment. This was a wait-listed two-armed-matched case-control study. Eighty (41 yoga, 39 control) visual impairment students of both genders aged 9-16 years matched on age, gender and degree of blindness were assessed at pre, mid (after 8 weeks) and post (after 16 weeks) yoga intervention using the Kraus-Weber test. The percentage of students passed in yoga group were 12.2%, 43.9% and 68.3% whereas percentages in the control group were 23.1%, 30.8% and 30.8% in pre, mid, and post tests respectively. McNemar test showed significant differences between pre and mid, mid and post in the yoga group while those parameters were not significantly different in the control group. Yoga therapy seemed to have considerable benefits for the children's muscular fitness. The study suggests that yoga have considerable benefits for improvement of fitness level in children with visual impairment and may be recommended as and effective, alternative, inexpensive low risk training activity option for them.
Generalized Hofmann quantum process fidelity bounds for quantum filters
NASA Astrophysics Data System (ADS)
Sedlák, Michal; Fiurášek, Jaromír
2016-04-01
We propose and investigate bounds on the quantum process fidelity of quantum filters, i.e., probabilistic quantum operations represented by a single Kraus operator K . These bounds generalize the Hofmann bounds on the quantum process fidelity of unitary operations [H. F. Hofmann, Phys. Rev. Lett. 94, 160504 (2005), 10.1103/PhysRevLett.94.160504] and are based on probing the quantum filter with pure states forming two mutually unbiased bases. Determination of these bounds therefore requires far fewer measurements than full quantum process tomography. We find that it is particularly suitable to construct one of the probe bases from the right eigenstates of K , because in this case the bounds are tight in the sense that if the actual filter coincides with the ideal one, then both the lower and the upper bounds are equal to 1. We theoretically investigate the application of these bounds to a two-qubit optical quantum filter formed by the interference of two photons on a partially polarizing beam splitter. For an experimentally convenient choice of factorized input states and measurements we study the tightness of the bounds. We show that more stringent bounds can be obtained by more sophisticated processing of the data using convex optimization and we compare our methods for different choices of the input probe states.
Hoarding behavior among young children with obsessive-compulsive disorder
Frank, Hannah; Stewart, Elyse; Walther, Michael; Benito, Kristen; Freeman, Jennifer; Conelea, Christ; Garci, Abbe
2014-01-01
Previous research has shown that among the various subtypes of obsessive-compulsive disorder (OCD), adults (e.g. Frost, Krause & Steketee, 1996) and older children and adolescents (Bloch et al., 2009; Storch et al., 2007) with problematic hoarding have distinct features and a poor treatment prognosis. However, there is limited information on the phenomenology and prevalence of hoarding behaviors in young children. The present study characterizes children ages 10 and under who present with OCD and hoarding behaviors. Sixty-eight children received a structured interview-determined diagnosis of OCD. Clinician administered, parent-report, and child-report measures on demographic, symptomatic, and diagnostic variables were completed. Clinician ratings of hoarding symptoms and parent and child endorsement of the hoarding item on the CY-BOCS checklist (Scahill, Riddle, McSwiggin-Hardin, & Ort, 1997) determined inclusion in the hoarding group (n=33). Compared to children without hoarding symptoms (n=35), the presence of hoarding symptoms was associated with an earlier age of primary diagnosis onset and a higher proportion of ADHD and provisional anxiety diagnoses. These results are partially consistent with the adult literature and with findings in older children (Storch et al., 2007). Additional data on clinical presentation and phenomenology of hoarding are needed to form a developmentally appropriate definition of the behavior. PMID:24860725
Performances of a Compact, High-Power WB Source with Circular Polarization
NASA Astrophysics Data System (ADS)
Delmote, P.; Pinguet, S.; Bieth, F.
This paper presents the design and the performances of an embedded high-power microwave (HPM) wideband source, developed and built at the French-German Research Institute of Saint-Louis. The system was intended for dual use, homeland security, and military applications. It is powered by a 400 kV compact Marx generator with specificities in coaxial design and low energy. The slow monopolar signal from the Marx is sharpened using a pulse-forming stage, made of a switching module pressurized with nitrogen, followed by a monopulse-to-monocycle converter. The duration and rise times of this signal could be adjusted by varying the pressure and space between electrodes. Repetitive operations were performed up to 100 Hz during 10 s without a gas flow. Two kinds of antennas can be connected to the source. The first one is a TEM horn, with an optional dielectric lens, that radiates a vertically polarized UWB short pulse. The second one is a nine-turn helix, working in Kraus monopolar axial mode and radiating a circularly polarized wideband signal along the main axis. A dedicated conical reflector increases its directivity and bandwidth. The whole source is designed to be embedded inside an aluminum trailer, powered by batteries and remote controlled through an optical fiber.
NASA Astrophysics Data System (ADS)
Wyborn, Lesley; Evans, Ben; Foster, Clinton; Pugh, Timothy; Uhlherr, Alfred
2015-04-01
Digital geoscience data and information are integral to informing decisions on the social, economic and environmental management of natural resources. Traditionally, such decisions were focused on regional or national viewpoints only, but it is increasingly being recognised that global perspectives are required to meet new challenges such as predicting impacts of climate change; sustainably exploiting scarce water, mineral and energy resources; and protecting our communities through better prediction of the behaviour of natural hazards. In recent years, technical advances in scientific instruments have resulted in a surge in data volumes, with data now being collected at unprecedented rates and at ever increasing resolutions. The size of many earth science data sets now exceed the computational capacity of many government and academic organisations to locally store and dynamically access the data sets; to internally process and analyse them to high resolutions; and then to deliver them online to clients, partners and stakeholders. Fortunately, at the same time, computational capacities have commensurately increased (both cloud and HPC): these can now provide the capability to effectively access the ever-growing data assets within realistic time frames. However, to achieve this, data and computing need to be co-located: bandwidth limits the capacity to move the large data sets; the data transfers are too slow; and latencies to access them are too high. These scenarios are driving the move towards more centralised High Performance (HP) Infrastructures. The rapidly increasing scale of data, the growing complexity of software and hardware environments, combined with the energy costs of running such infrastructures is creating a compelling economic argument for just having one or two major national (or continental) HP facilities that can be federated internationally to enable earth and environmental issues to be tackled at global scales. But at the same time, if properly constructed, these infrastructures can also service very small-scale research projects. The National Computational Infrastructure (NCI) at the Australian National University (ANU) has built such an HP infrastructure as part of the Australian Government's National Collaborative Research Infrastructure Strategy. NCI operates as a formal partnership between the ANU and the three major Australian National Government Scientific Agencies: the Commonwealth Scientific and Industrial Research Organisation (CSIRO), the Bureau of Meteorology and Geoscience Australia. The government partners agreed to explore the new opportunities offered within the partnership with NCI, rather than each running their own separate agenda independently. The data from these national agencies, as well as from collaborating overseas organisations (e.g., NASA, NOAA, USGS, CMIP, etc.) are either replicated to, or produced at, NCI. By co-locating and harmonising these vast data collections within the integrated HP computing environments at NCI, new opportunities have arisen for Data-intensive Interdisciplinary Science at scales and resolutions not hitherto possible. The new NCI infrastructure has also enabled the blending of research by the university sector with the more operational business of government science agencies, with the fundamental shift being that researchers from both sectors work and collaborate within a federated data and computational environment that contains both national and international data collections.
NASA Astrophysics Data System (ADS)
Brensons, I.; Polukoshko, S.
2013-10-01
Fused deposition modelling (FDM) is one of the most effective rapid prototyping (RP) techniques due to its low cost, available materials and versatility. In FDM, a part of material (usually plastic) is made by heating this material to the molten state, and from the melt it is extruded through a nozzle and deposited on a surface. In the article, an alternative RP method is considered for improvement of the mechanical properties of a rapid prototype. The authors propose an analytical solution which allows for achievement of this purpose via advanced technologies. The base materials applied in RP technology can be combined with liquid resin which solidifies after a definite time. This makes it possible to create a channel through the prototype and fill it with another material having better mechanical properties. The optimal channel sizes can be chosen in order to raise the strength of material parts. Darbā tiek apskatīts ātrās prototipēšanas veids, kura pamatā ir detaļas veidošana, izmantojot kausētu materiālu parasti plastmasu. Šī detaļu veidošanas metode ir kļuvusi par vienu no visizplatītākajām tās zemo izmaksu, pieejamo materiālu un daudzpusības dēļ. Šī raksta mērķis ir izpētīt alternatīvu veidu, kā uzlabot prototipu mehāniskās īpašības, tādējādi palielinot printētu detaļu izmantošanu kā gala produktu. Raksts piedāvā analītisku risinājumu, kā uzlabot ātro prototipu mehāniskās īpašības, uzlabojot tehnoloģiskos procesus, kas iesaistīti detaļu izgatavošanā. Darba pamatā tiek izmantota 3D printēšanas tehnoloģijas iespēja veidot iekšējus kanālus bez ģeometriskiem ierobežojumiem, kā rezultātā ir iespējams izveidot iekšēju kanālu shēmu, ko pēc tam piepilda ar citu materiālu, kam ir labākas mehāniskās īpašības kā pamata materiālam. Pildīšanai izmantotais materiāls ir epoksīda sveķi, kas pieļauj vieglu iepildīšanu šķidrā fāzē, un sniedz labas mehāniskās īpašības pēc sacietēšanas. Analītiskais risinājums šajā rakstā piedāvā viegli realizējamu variantu kā būtiski uzlabot prototipu mehāniskās īpašības.
Hidden Variables and Placebo Effects
NASA Astrophysics Data System (ADS)
Goradia, Shantilal
2006-03-01
God's response to prayers and placebo leads to a question. How does He respond deterministically? He may be controlling at least one of the two variables of the uncertainty principle by extending His invisible soul to each body particle locally. Amazingly, many Vedic verses support this answer. One describes the size of the soul as arithmetically matching the size of the nucleons as if a particle is a soul. One gives a name meaning particle soul (anu-atma), consistent with particle's indeterministic behavior like that of (soulful) bird’s flying in any directions irrespective of the direction of throw. One describes souls as eternal consistent with the conservation of baryon number. One links the souls to the omnipresent (param- atma) like Einstein Rosen bridges link particles to normal spacetime. One claims eternal coexistence of matter and soul as is inflationary universe in physics/0210040 V2. The implicit scientific consistency of such verses makes the relationship of particle source of consciousness to the omnipresent Supreme analogous to the relationship of quantum source of gravitons in my gr-qc/0507130 to normal spacetime This frees us from the postulation of quantum wormholes and quantum foam. Dr. Hooft's view in ``Does God play dice,'' Physicsword, Dec 2005 seems consistent with my progressive conference presentations in Russia, Europe, India, and USA (Hindu University) in 2004/05. I see implications for nanoscience.
Seven new carbon-enhanced metal-poor RR Lyrae stars
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kennedy, Catherine R.; Stancliffe, Richard J.; Kuehn, Charles
2014-05-20
We report estimated carbon-abundance ratios, [C/Fe], for seven newly discovered carbon-enhanced metal-poor (CEMP) RR Lyrae stars. These are well-studied RRab stars that had previously been selected as CEMP candidates based on low-resolution spectra. For this pilot study, we observed eight of these CEMP RR Lyrae candidates with the Wide Field Spectrograph on the ANU 2.3 m telescope. Prior to this study, only two CEMP RR Lyrae stars had been discovered: TY Gru and SDSS J1707+58. We compare our abundances to new theoretical models of the evolution of low-mass stars in binary systems. These simulations evolve the secondary stars, post accretionmore » from an asymptotic giant-branch (AGB) donor, all the way to the RR Lyrae stage. The abundances of CEMP RR Lyrae stars can be used as direct probes of the nature of the donor star, such as its mass, and the amount of material accreted onto the secondary. We find that the majority of the sample of CEMP RR Lyrae stars is consistent with AGB donor masses of around 1.5-2.0 M {sub ☉} and accretion masses of a few hundredths of a solar mass. Future high-resolution studies of these newly discovered CEMP RR Lyrae stars will help disentangle the effects of the proposed mixing processes that occur in such objects.« less
NASA Astrophysics Data System (ADS)
Hampton, E. J.; Medling, A. M.; Groves, B.; Kewley, L.; Dopita, M.; Davies, R.; Ho, I.-T.; Kaasinen, M.; Leslie, S.; Sharp, R.; Sweet, S. M.; Thomas, A. D.; Allen, J.; Bland-Hawthorn, J.; Brough, S.; Bryant, J. J.; Croom, S.; Goodwin, M.; Green, A.; Konstantantopoulos, I. S.; Lawrence, J.; López-Sánchez, Á. R.; Lorente, N. P. F.; McElroy, R.; Owers, M. S.; Richards, S. N.; Shastri, P.
2017-09-01
Integral field spectroscopy (IFS) surveys are changing how we study galaxies and are creating vastly more spectroscopic data available than before. The large number of resulting spectra makes visual inspection of emission line fits an infeasible option. Here, we present a demonstration of an artificial neural network (ANN) that determines the number of Gaussian components needed to describe the complex emission line velocity structures observed in galaxies after being fit with lzifu. We apply our ANN to IFS data for the S7 survey, conducted using the Wide Field Spectrograph on the ANU 2.3 m Telescope, and the SAMI Galaxy Survey, conducted using the SAMI instrument on the 4 m Anglo-Australian Telescope. We use the spectral fitting code lzifu (Ho et al. 2016a) to fit the emission line spectra of individual spaxels from S7 and SAMI data cubes with 1-, 2- and 3-Gaussian components. We demonstrate that using an ANN is comparable to astronomers performing the same visual inspection task of determining the best number of Gaussian components to describe the physical processes in galaxies. The advantage of our ANN is that it is capable of processing the spectra for thousands of galaxies in minutes, as compared to the years this task would take individual astronomers to complete by visual inspection.
Rhizobium cellulase CelC2 is essential for primary symbiotic infection of legume host roots
Robledo, M.; Jiménez-Zurdo, J. I.; Velázquez, E.; Trujillo, M. E.; Zurdo-Piñeiro, J. L.; Ramírez-Bahena, M. H.; Ramos, B.; Díaz-Mínguez, J. M.; Dazzo, F.; Martínez-Molina, E.; Mateos, P. F.
2008-01-01
The rhizobia–legume, root-nodule symbiosis provides the most efficient source of biologically fixed ammonia fertilizer for agricultural crops. Its development involves pathways of specificity, infectivity, and effectivity resulting from expressed traits of the bacterium and host plant. A key event of the infection process required for development of this root-nodule symbiosis is a highly localized, complete erosion of the plant cell wall through which the bacterial symbiont penetrates to establish a nitrogen-fixing, intracellular endosymbiotic state within the host. This process of wall degradation must be delicately balanced to avoid lysis and destruction of the host cell. Here, we describe the purification, biochemical characterization, molecular genetic analysis, biological activity, and symbiotic function of a cell-bound bacterial cellulase (CelC2) enzyme from Rhizobium leguminosarum bv. trifolii, the clover-nodulating endosymbiont. The purified enzyme can erode the noncrystalline tip of the white clover host root hair wall, making a localized hole of sufficient size to allow wild-type microsymbiont penetration. This CelC2 enzyme is not active on root hairs of the nonhost legume alfalfa. Microscopy analysis of the symbiotic phenotypes of the ANU843 wild type and CelC2 knockout mutant derivative revealed that this enzyme fulfils an essential role in the primary infection process required for development of the canonical nitrogen-fixing R. leguminosarum bv. trifolii-white clover symbiosis. PMID:18458328
Defeating diplostomoid dangers in USA catfish aquaculture.
Overstreet, Robin M; Curran, Stephen S
2004-06-01
Diplostomoid digenean metacercariae have caused widescale mortalities of channel catfish, Ictalurus punctatus (Rafinesque), at aquaculture farms in Louisiana, Mississippi and Arkansas, USA. Originally, based on a tentative diagnosis, the industry considered the primary harmful agent to be an introduced species from Europe, Bolbophorus confusus (Krause, 1914), frequently reported from the American white pelican, Pelecanus erythrorhynchos Gmelin. Our group has now shown, using ITS 1-2 plus three more-conservative gene fragments, that two sympatric species of Bolbophorus exist in the American white pelican. One, B. damnificus Overstreet et Curran, 2002, infects the musculature of catfish, and the other, probably not B. confusus, does not infect catfish. However, at least four other pathogenic diplostomoids and a clinostomoid infect the catfish, and they use at least four different snail hosts, including the planorbids Planorbella trivolvis (Say) and Gyraulus parvus (Say), the physid Physella gyrina (Say) and a lymnaeid. Two metacercariae, B. damnificus and Bursacetabulus pelecanus Dronen, Tehrany et Wardle, 1999, infect the catfish and mature in the pelican; two others, Austrodiplostomum compactum (Lutz, 1928) and Hysteromorpha cf. triloba (Rudolphi, 1819), mature in cormorants; one, Diplostomum sp., matures in seagulls and at least one, Clinostomum marginatum (Rudolphi, 1819), matures in herons, egrets and other wading birds. Consequently, management of catfish ponds relative to digenean infections requires considerable biological information on the fish, bird, and snail hosts as well as the parasites.
A Translational Model of Research-Practice Integration
Vivian, Dina; Hershenberg, Rachel; Teachman, Bethany A.; Drabick, Deborah A. G.; Goldfried, Marvin R.; Wolfe, Barry
2013-01-01
We propose a four-level, recursive Research-Practice Integration framework as a heuristic to (a) integrate and reflect on the articles in this Special Section as contributing to a bidirectional bridge between research and practice, and (b) consider additional opportunities to address the research–practice gap. Level 1 addresses Treatment Validation studies and includes an article by Lochman and colleagues concerning the programmatic adaptation, implementation, and dissemination of the empirically supported Coping Power treatment program for youth aggression. Level 2 translation, Training in Evidence-Based Practice, includes a paper by Hershenberg, Drabick, and Vivian, which focuses on the critical role that predoctoral training plays in bridging the research–practice gap. Level 3 addresses the Assessment of Clinical Utility and Feedback to Research aspects of translation. The articles by Lambert and Youn, Kraus, and Castonguay illustrate the use of commercial outcome packages that enable psychotherapists to integrate ongoing client assessment, thus enhancing the effectiveness of treatment implementation and providing data that can be fed back to researchers. Lastly, Level 4 translation, the Cross-Level Integrative Research and Communication, concerns research efforts that integrate data from clinical practice and all other levels of translation, as well as communication efforts among all stakeholders, such as researchers, psychotherapists, and clients. Using a two-chair technique as a framework for his discussion, Wolfe's article depicts the struggle inherent in research–practice integration efforts and proposes a rapprochement that highlights advancements in the field. PMID:22642522
NASA Astrophysics Data System (ADS)
Korzekwa, Kamil; Czachórski, Stanisław; Puchała, Zbigniew; Życzkowski, Karol
2018-04-01
Is it always possible to explain random stochastic transitions between states of a finite-dimensional system as arising from the deterministic quantum evolution of the system? If not, then what is the minimal amount of randomness required by quantum theory to explain a given stochastic process? Here, we address this problem by studying possible coherifications of a quantum channel Φ, i.e., we look for channels {{{Φ }}}{ \\mathcal C } that induce the same classical transitions T, but are ‘more coherent’. To quantify the coherence of a channel Φ we measure the coherence of the corresponding Jamiołkowski state J Φ. We show that the classical transition matrix T can be coherified to reversible unitary dynamics if and only if T is unistochastic. Otherwise the Jamiołkowski state {J}{{Φ }}{ \\mathcal C } of the optimally coherified channel is mixed, and the dynamics must necessarily be irreversible. To assess the extent to which an optimal process {{{Φ }}}{ \\mathcal C } is indeterministic we find explicit bounds on the entropy and purity of {J}{{Φ }}{ \\mathcal C }, and relate the latter to the unitarity of {{{Φ }}}{ \\mathcal C }. We also find optimal coherifications for several classes of channels, including all one-qubit channels. Finally, we provide a non-optimal coherification procedure that works for an arbitrary channel Φ and reduces its rank (the minimal number of required Kraus operators) from {d}2 to d.
Surgical approach to pineal tumours.
Pluchino, F; Broggi, G; Fornari, M; Franzini, A; Solero, C L; Allegranza, A
1989-01-01
During a period of 10 years (1977-1986) 40 cases of tumour of the pineal region have been treated at the Istituto Neurologico "C. Besta"-of Milan. Out of these 40 cases, 27 (67.5%) were in the paediatric (10-15 years) or juvenile (15-20 years) age at the time of operation. Since 1983 a specific diagnostic and therapeutic protocol has been adopted and thereafter direct surgical removal of the tumour was performed only when the neuroradiological investigations were highly suggestive of a benign extrinsic lesion. Sixteen cases in this series underwent direct surgical removal; in the remaining 24 cases stereotactic biopsy of the tumour was performed in the first instance. On the basis of the histological diagnosis obtained by this procedure surgical excision of the tumour (9 cases) or radiotherapy (15 cases) was then performed. 25 cases underwent surgical removal of the lesion. In all the cases the infratentorial supracerebellar approach as introduced by Krause and then modified by Stein was adopted. On analysis of the data of this series it was observed that in 25% of the cases completely benign resectable tumours were found; in 25% of the cases astrocytoma (grade I-II) which could be treated at least by partial removal were present; in 30% of the cases radiosensitive lesions were encountered. In the remaining 20% of the cases highly malignant tumours were found which should be treated only by radiotherapy and/or chemotherapy.
Yoga Practice Increases Minimum Muscular Fitness in Children with Visual Impairment
Mohanty, Soubhagyalaxmi; Venkata Ramana Murty, Peri; Pradhan, Balaram; Hankey, Alex
2015-01-01
Introduction: Muscle strength, a component for balance, gait and functional mobility is vital for children with visual impairment. Yoga has frequently been demonstrated to improve physical and mental fitness in children. This study aimed to assess the effect of 16 weeks yoga training on muscular fitness in children with visual impairment. Methods: This was a wait-listed two-armed-matched case–control study. Eighty (41 yoga, 39 control) visual impairment students of both genders aged 9-16 years matched on age, gender and degree of blindness were assessed at pre, mid (after 8 weeks) and post (after 16 weeks) yoga intervention using the Kraus-Weber test. Results: The percentage of students passed in yoga group were 12.2%, 43.9% and 68.3% whereas percentages in the control group were 23.1%, 30.8% and 30.8% in pre, mid, and post tests respectively. McNemar test showed significant differences between pre and mid, mid and post in the yoga group while those parameters were not significantly different in the control group. Yoga therapy seemed to have considerable benefits for the children’s muscular fitness. Conclusion: The study suggests that yoga have considerable benefits for improvement of fitness level in children with visual impairment and may be recommended as and effective, alternative, inexpensive low risk training activity option for them. PMID:26744725
[Signs of extreme vagotonia in the electrocardiogram of an Olympic 5km running champion].
Chrástek, J
2002-12-01
Hypokinesia (lack of exercise)--a disease caused by lack of physical activity leads among others to a predominance of the sympathetic nerve in the circulation. Its manifestations are briefly described according to Kraus-Raab's hypothesis of 1961. The opposite of a hypokinetic man are trained (hyperkinetic) sportsmen, in particular long-distance runners. Their neurovegetative balance is shifted to the side of the vagus (parasympathetic nerve). This is described as training vagotonia. On the example of ECG tracings of an Olympic 5 km runner, the Tunisian Mohamed Gammoudi, the author describes its manifestations at rest, during the orthostatic test and during work, i.e. the step test. These manifestations include in particular bradycardia of 32 beats per minute, prolonged atrioventricular conduction > 0.2 sec., a long period of the electric systole = 0.44 sec. and an enormously prolonged electric diastole T-P = 1.1 sec. This long diastolic filling stage makes it possible in particular during physical work to increase the systolic and diastolic output to double the values of a healthy non-trained heart. Training vagotonia is usually not the source for manifestation of dangerous arrhythmias, as it may be the case in constitutional vagotonia. So far expert comparison of these two types of change to parasympathic tonus is lacking, similarly as a comparative study with medicamentously influenced vagotonia by means of beta-blockers.
VizieR Online Data Catalog: The factory & the beehive. III. PTFEB132.707+19.810 (Kraus+, 2017)
NASA Astrophysics Data System (ADS)
Kraus, A. L.; Douglas, S. T.; Mann, A. W.; Agueros, M. A.; Law, N. M.; Covey, K. R.; Feiden, G. A.; Rizzuto, A. C.; Howard, A. W.; Isaacson, H.; Gaidos, E.; Torres, G.; Bakos, G.
2018-03-01
The PTF uses wide-field photometric observations from the robotic 48 inch Samuel Oschin Telescope (P48). When PTFEB132.707+19.810 was observed in 2010 and 2011, P48 was equipped with the CFH12K mosaic camera. PTFEB132.707+19.810 was observed as EPIC211972086 by the Kepler spacecraft during Campaign 5 of its repurposed K2 mission (Howell+ 2014PASP..126..398H), for which it was proposed as a target by eight proposals, including ours (GO5095; PI: Agueros). K2 observed PTFEB132.707+19.810 in long-cadence mode (tint=29.4minutes) for 73.9 continuous days spanning 2015 April 27-July 10. After our discovery of eclipses in this system in 2010, we began a spectroscopic monitoring campaign to measure radial velocities for the components. We obtained 20 high-dispersion spectra for the system using Keck I and the HIRES spectrograph (resolution of R~48000). We also obtained an optical spectrum of PTFEB132.707+19.810 on 2016 April 3 with SNIFS on the University of Hawai'i 2.2m telescope on Maunakea (R~1000 in blue channel). We obtained a NIR spectrum of PTFEB132.707+19.810 on 2016 April 5 with the SpeX spectrograph on the NASA Infrared Telescope Facility on Maunakea (R~2000). (3 data files).
Opinion dynamics in activity-driven networks
NASA Astrophysics Data System (ADS)
Li, Dandan; Han, Dun; Ma, Jing; Sun, Mei; Tian, Lixin; Khouw, Timothy; Stanley, H. Eugene
2017-10-01
Social interaction between individuals constantly affects the development of their personal opinions. Previous models such as the Deffuant model and the Hegselmann-Krause (HK) model have assumed that individuals only update their opinions after interacting with neighbors whose opinions are similar to their own. However, people are capable of communicating widely with all of their neighbors to gather their ideas and opinions, even if they encounter a number of opposing attitudes. We propose a model in which agents listen to the opinions of all their neighbors. Continuous opinion dynamics are investigated in activity-driven networks with a tolerance threshold. We study how the initial opinion distribution, tolerance threshold, opinion-updating speed, and activity rate affect the evolution of opinion. We find that when the initial fraction of positive opinion is small, all opinions become negative by the end of the simulation. As the initial fraction of positive opinions rises above a certain value —about 0.45— the final fraction of positive opinions sharply increases and eventually equals 1. Increased tolerance threshold δ is found to lead to a more varied final opinion distribution. We also find that if the negative opinion has an initial advantage, the final fraction of negative opinion increases and reaches its peak as the updating speed λ approaches 0.5. Finally we show that the lower the activity rate of individuals, the greater the fluctuation range of their opinions.
Preface: 18th Aps-Sccm and 24th Airapt
NASA Astrophysics Data System (ADS)
Collins, Gilbert; Moore, David S.; Yoo, Choong-Shik; Buttler, William; Furlanetto, Michael; Evans, William
2014-05-01
The 18th Biennial International Conference of the APS Topical Group on Shock Compression of Condensed Matter in conjunction with the 24th Biennial International Conference of the International Association for the Advancement of High Pressure Science & Technology (AIRAPT) was held at the Westin Hotel in Seattle, Washington from 7-12 July, 2013. This is only the second time that these two organizations have held a Joint Conference — the first was 20 years previous (1993) in Colorado Springs, Colorado. Seattle was chosen for this joint conference because of its central location for the world-wide attendees as well as its metropolitan vibrancy. The scientific program consisted of 858 scheduled presentations organized into 23 topical areas and included contributed (537), invited (95), and plenary (6) lectures, as well as two poster sessions with 110 posters each. The scientific focus of the Joint Conference was on fundamental and applied research topics related to the static or dynamic compression of condensed matter. This multidisciplinary field of research encompasses areas of physics, chemistry, materials science, mechanics, geophysics and planetary physics, and applied mathematics. Experimental, computational and theoretical studies all play important roles. The organizers endeavored to intertwine static and dynamic experimental alongside computational and theoretical studies of similar materials in the organization of the sessions. This goal was aided by the addition of three special focus sessions on deep carbon budget, high energy density materials, and dynamic response of materials. 722 scientists and engineers from 25 countries registered at the conference, including 132 students from 12 countries. The attendee countries represented included: Argentina (2), Australia (2), Brazil (3), Canada (25), China (22), Czech Republic (2), France (35), Germany (19), India (6), Israel (21), Italy (10), Japan (49), Netherlands (1), Poland (1), Portugal (2), Russia (26), Singapore (1), Slovakia (1), South Korea (5), Spain (7), Sweden (4), Switzerland (1), United Kingdom (69), United States of America (402). 79 of the students were supported by travel awards, funded in part by the APS Topical Group, the AIRAPT, and other sources. New for this conference was an expanded Student Program, including an all-day Student, Post-Doc, and Early Career Symposium held on Sunday 7 July . During the Conference, Gennady Kanel of the Institute for High Temperatures, Russian Academy of Sciences, was presented the 2013 George E Duval Shock Compression Science Award, and gave a plenary lecture ''Unusual behavior of usual materials in shock waves.'' Similarly, Karl Syassen of the Max Planck Institute Stuttgart received the 2013 Percy Bridgman Award at the conference, and presented a plenary lecture ''Stressed solids probed by diffraction and spectroscopy.'' In addition, there were two young investigator awards presented. First was the AIRAPT Jamieson Award, presented to Duck Young Kim of the Geophysical Laboratory, Carnegie Institution of Washington, DC. The other was a new APS SCCM Topical Group Student Award, presented to Rick Kraus of Harvard University. The two awardees shared a plenary talk slot on 8 July, with Duck Young Kim presenting ''Novel materials prediction and experimental synthesis under pressure'' and Rick Kraus ''Thermodynamic paths in planetary collisions: Shock vaporization of SiO2, MgO, and Fe.'' Details of the committees are available in the PDF
Downing, Bryan D.; Bergamaschi, Brian A.; Kraus, Tamara E.C.
2017-07-11
Executive SummaryThis report is the second in a series of three reports that provide information about high-frequency (HF) nutrient and biogeochemical monitoring in the Sacramento–San Joaquin Delta of northern California (Delta). The purpose of this report is to synthesize the data available from a nutrient and water-quality HF (about every 15 minutes) monitoring network operated by the U.S. Geological Survey in the northern Delta. In this report, we describe the network and focus on the purpose of each station. We then present and discuss the available data, at various timescales—first at the monthly, seasonal, and inter-annual timescales, and second, for comparison, at the tidal and event timescales. As expected, we determined that there is substantial variability in nitrate-N concentrations at short timescales within hours, but also significant variability at longer timescales such as months or years. Resolving this variability is made possible by the HF data, with the largest variability caused by storms, tides, and diel biological processes. Given this large temporal variability, calculations of cumulative nutrient fluxes (for example, daily, monthly, or annual loads) is difficult without HF data. For example, in the Cache Slough, calculation of the annual load without the tidal variability resulted in a 30 percent underestimation of the true annual load value. We conclude that HF measurements are important for accurate determination of fluxes and loads in tidal environments, but, more importantly, provide important insights into processes and rates of nutrient cycling.This report, along with the other two reports of this series (Bergamaschi and others, 2017; Kraus, Bergamaschi, and others, 2017), was drafted in cooperation with the Delta Regional Monitoring Program to help scientists, managers, and planners understand how HF data improve our understanding of nutrient sources and sinks, drivers, and effects in the Delta. The first report in the series (Kraus, Bergamaschi, and others, 2017) provides an introduction to the reasons for and fundamental concepts behind using HF monitoring measurements, including a brief summary of nutrient status and trends in the Delta and an extensive literature review showing how and where other research and monitoring programs have used HF monitoring to improve our understanding of nutrient cycling. The report covers the various technologies available for HF nutrient monitoring and presents the different ways HF monitoring instrumentation may be used for fixed station and spatial assessments. Finally, it presents numerous examples of how HF measurements are currently (2017) being used in the Delta to examine how nutrients and nutrient cycling are related to aquatic habitat conditions.The third report in the series (Bergamaschi and others, 2017) provides the background, principles, and considerations for designing an HF nutrient-monitoring network for the Delta to address high-priority, nutrient-management questions. The report starts with discussion of the high‑priority management questions to be addressed, continues through discussion of the questions and considerations that place demands and constraints on network design, discusses the principles applicable to network design, and concludes with the presentation of three example nutrient-monitoring network designs for the Delta, proposed to address high-priority questions identified by the Delta Regional Monitoring Program (Delta Regional Monitoring Program Technical Advisory Committee, 2015).
Glasgow, Nicholas J; Wells, Robert; Butler, James; Gear, Anna
2008-04-21
To review the literature on the effectiveness of competency-based education (CBE) as a means of equipping the Australian general practice workforce to deliver optimal chronic disease outcomes to articulate policy options for the Australian context. Systematic review of the literature (1991-2005) using a narrative approach followed by analysis of the findings using the actors/context/ processes/content framework of Buse et al. Few high-quality studies were identified. National policy options include incorporating clear statements about education and training, research and evaluation in any policy document targeting chronic disease; and provision of funding to enhance general practice teaching facilities and/or facilitate the development of supportive coordinating and administrative structures for training practices. Designers of CBE should consider five key questions: Are the educational objectives of the CBE clearly aligned with the chronic disease or workforce-related outcomes of interest? Is the design of the CBE sound? Have similar educational programs targeting the same outcomes been identified and every attempt made to maximise synergies between programs? Are the educational designers fully aware of and working within the existing complexity of the training environment? Are all involved in the program actively managing the process of change? Policy options range from those relatively simple and achievable to more complex and difficult. The full report is available at http://www.anu.edu.au/aphcri/Domain/Workforce/final_25_glasgow.pdf.
Analytical Treatment of Forecasts of Electric Energy Consumption in Latvia
NASA Astrophysics Data System (ADS)
Balodis, M.; Gavars, V.; Andersons, J.
2014-06-01
In the paper, the changes in electric energy consumption are analyzed as associated with structural changes in the Latvian economy of postsocialistic period. To the analysis, a particular approach is applied, which consists in comparison of the basic and specific electricity consumption indices in West-, Central-, and East-European states for the time span of 1990-2010, with differences and tendencies of changes revealed. Tendencies of the type are determined for the electric energy consumption in Latvia, and recommendations are given for the use of such indices in the relevant forecasts. Rakstā apskatītas elektroenerģijas patēriņa izmaiņas, kas saistītas ar Latvijas postsociālisma perioda ekonomikas strukturālām izmaiņām. Rakstā dota Latvijas galveno elektroenerģijas patēriņa indikatoru analīze, lietojot īpašu pieeju - Rietumeiropas, Centrāleiropas un Austrumeiropas valstu indikatoru salīdzinājumu. Analizēts periods no 1990. gada līdz 2010. gadam. Salīdzināti Eiropas valstu grupu īpatnējie elektroenerģijas patēriņa indikatori un noskaidrotas to atšķirības un izmaiņu tendences. Noteiktas elektroenerģijas patēriņa izmaiņu tendences Latvijā. Dotas rekomendācijas par šo indikatoru izmantošanu elektroenerģijas patēriņa prognozēšanā. 07.05.2014.
Prehistory of Zodiac Dating: Three Strata of Upper Paleolithic Constellations
NASA Astrophysics Data System (ADS)
Gurshtein, Alex A.
A pattern of archaic proto-constellations is extracted from Aratus' "The Phaenomena" didactic poem list according to a size criterion elaborated earlier, and their symbolism is analyzed. As a result of this approach three celestial symbolical strata are discovered to be probably a reflection of the symbols for the Lower, the Middle and the Upper Worlds; the Under-World creatures have a water character, the Middle World ones are mostly anthropomorphic and flying beings are for the Upper World. The strata excerpted from Aratus' sky seems to be in agreement with the well-known Babylonian division into three god pathways for Ea (Enki), Anu and Enlil. There is a possibility of dating the pattern discovered because of precession's strong influence as far back as 16 thousand years, the result being supported by the comparison of different star group mean sizes. The archaic constellation pattern under consideration is a reasonable background of symbolical meanings for the first Zodiacal generation quartet (7.5 thousand years old) examined by the author previously. The enormous size of the Argo constellation (Ship of Argo and his Argonauts) as well as the large sizes of other southern constellations are explained as due to the existence of an accumulation zone near the South celestial pole. Some extra correlations between the reconstruction proposed and cultural data available are discussed. The paper is the second part of the investigation "On the Origin of the Zodiacal constellations" published in Vistas in Astronomy, vol.36, pp.171-190, 1993.
SDN solutions for switching dedicated long-haul connections: Measurements and comparative analysis
Rao, Nageswara S. V.
2016-01-01
We consider a scenario of two sites connected over a dedicated, long-haul connection that must quickly fail-over in response to degradations in host-to-host application performance. The traditional layer-2/3 hot stand-by fail-over solutions do not adequately address the variety of application degradations, and more recent single controller Software Defined Networks (SDN) solutions are not effective for long-haul connections. We present two methods for such a path fail-over using OpenFlow enabled switches: (a) a light-weight method that utilizes host scripts to monitor application performance and dpctl API for switching, and (b) a generic method that uses two OpenDaylight (ODL) controllers and RESTmore » interfaces. For both methods, the restoration dynamics of applications contain significant statistical variations due to the complexities of controllers, north bound interfaces and switches; they, together with the wide variety of vendor implementations, complicate the choice among such solutions. We develop the impulse-response method based on regression functions of performance parameters to provide a rigorous and objective comparison of different solutions. We describe testing results of the two proposed methods, using TCP throughput and connection rtt as main parameters, over a testbed consisting of HP and Cisco switches connected over longhaul connections emulated in hardware by ANUE devices. Lastly, the combination of analytical and experimental results demonstrate that the dpctl method responds seconds faster than the ODL method on average, even though both methods eventually restore original TCP throughput.« less
NASA Astrophysics Data System (ADS)
Grinevich, I.; Mozga, N.; Rudzitis, J.
2013-10-01
The electrical energy consumption of battery-operated screwdrivers, which are widely used in many industries, e.g. automotive, heavy, chemical, etc., can be considerably reduced. This would allow increasing the service life of a battery and reducing the time of its charging, thus increasing the productivity and decreasing the prime cost of this battery. It is shown that up to 17.9% of electrical energy could be saved at assembling fixed threaded joints by removing power from the screwdriver immediately after reaching the required tightening torque. Dotajā rakstā uzmanība tiek pievērsta akumulatora skrūvgrieža elektroenerģijas patēriņa samazināšanas iespējām sakarā ar problēmas aktualitāti šīs grupas plaši pielietotajiem instrumentiem. Elektroenerģijas patēriņa samazināšana masveida ražošanā, kur tiek izmantoti akumulatora skrūvgrieži, ļautu paildzināt akumulatora baterijas kalpošanas mūžu un samazināt uzlādēšanas laiku, kas, savukārt, novestu pie ražības palielināšanas un produkcijas pašizmaksas samazināšanas.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dopita, Michael A.; Davies, Rebecca; Kewley, Lisa
2015-03-15
Here we describe the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) and present results on 64 galaxies drawn from the first data release. The S7 uses the Wide Field Spectrograph mounted on the ANU 2.3 m telescope located at the Siding Spring Observatory to deliver an integral field of 38 × 25 arcsec at a spectral resolution of R = 7000 in the red (530–710 nm), and R = 3000 in the blue (340–560 nm). From these data cubes we have extracted the narrow-line region spectra from a 4 arcsec aperture centered on the nucleus. We also determine themore » Hβ and [O iii] λ5007 fluxes in the narrow lines, the nuclear reddening, the reddening-corrected relative intensities of the observed emission lines, and the Hβ and [O iii] λ5007 luminosities determined from spectra for which the stellar continuum has been removed. We present a set of images of the galaxies in [O iii] λ5007, [N ii] λ6584, and Hα, which serve to delineate the spatial extent of the extended narrow-line region and also to reveal the structure and morphology of the surrounding H ii regions. Finally, we provide a preliminary discussion of those Seyfert 1 and Seyfert 2 galaxies that display coronal emission lines in order to explore the origin of these lines.« less
NASA Astrophysics Data System (ADS)
Kochukov, O.; Briņķis, K.; Mutule, A.
2013-08-01
The paper describes the algorithm for distributed state estimation (SE) and is focused on its testing and validation. For this purpose, different events in the modeled power system of the 330-750 kV electrical ring Latvia - Lithuania - Belarus - Smolensk - Moscow - St. Petersburg - Estonia - Latvia were considered. The methods for testing the Inter-TSO SE prototype and dynamic network monitoring & modeling are based on comparison of the available SCADA data about real events with those of SE calculation. In total, four operational states were studied, including initial, accident and two post-accident operational states Rakstā tiek aprakstīti, testēti un novērtēti izkliedēta stāvokļa novērtēšanas algoritmi. Testēšanas nolūkos tika izmantoti dažādi 330-750 kV elektriskā loka Latvija - Lietuva - Baltkrievija - Smoļenska - Maskava - Pēterburga - Igaunija - Latvija modelēti scenāriji. Prototipa testēšanas metodoloģija balstīta uz pieejamo SCADA datu salīdzināšanu ar stāvokļa novērtēšanas prototipa aprēķina rezultātiem. Kopumā apskatīti sākotnējais, avārijas un divi pēcavārijas režīmi
NASA Astrophysics Data System (ADS)
Seeley, Lane
2008-05-01
The United States faces a critical shortage of qualified physics and physical science teachers. The number of high school students taking physics is increasing but the number of physics majors pursuing careers in pre-college teaching is not nearly sufficient to meet the demand. College and university physics departments have content expertise and ready access to potential future teachers of physics. In order to address the crisis in physics and physical science education, APS, AAPT, and AIP have developed the PhysTEC project. Seattle Pacific University is one of six fully funded PhysTEC sites. The PhysTEC project also supports a coalition of more than one hundred institutions that are committed to improving K-12 physics and physical science education. This talk will describe the national PhysTEC project along with our local PhysTEC program. We will explore ways in which physics departments can more fully integrate the preparation of pre-college physics teachers within existing departmental priorities. We will discuss opportunities for regional partnerships between 2-year and 4-year colleges, school districts, and teacher preparation programs. We will also highlight ways in which our research on the learning and teaching of physics informs the development of tools that teachers and teacher educators can use to diagnose student ideas and to design subsequent instruction that capitalizes on these ideas. In collaboration with Stamatis Vokos, Seattle Pacific University and Pam Kraus, Facet Innovations LLC.
The 13Carbon footprint of B[e] supergiants
NASA Astrophysics Data System (ADS)
Liermann, A.; Kraus, M.; Schnurr, O.; Fernandes, M. Borges
2010-10-01
We report on the first detection of 13C enhancement in two B[e] supergiants (B[e]SGs) in the Large Magellanic Cloud. Stellar evolution models predict the surface abundance in 13C to strongly increase during main-sequence and post-main-sequence evolution of massive stars. However, direct identification of chemically processed material on the surface of B[e]SGs is hampered by their dense, disc-forming winds, hiding the stars. Recent theoretical computations predict the detectability of enhanced 13C via the molecular emission in 13CO arising in the circumstellar discs of B[e]SGs. To test this potential method and to unambiguously identify a post-main-sequence B[e] SG by its 13CO emission, we have obtained high-quality K-band spectra of two known B[e] SGs in the Large Magellanic Cloud, using the Very Large Telescope's Spectrograph for INtegral Field Observation in the Near-Infrared (VLT/SINFONI). Both stars clearly show the 13CO band emission, whose strength implies a strong enhancement of 13C, in agreement with theoretical predictions. This first ever direct confirmation of the evolved nature of B[e]SGs thus paves the way to the first identification of a Galactic B[e]SG. Based on observations collected with the ESO VLT Paranal Observatory under programme 384.D-1078(A). E-mail: liermann@mpifr-bonn.mpg.de (AL); kraus@sunstel.asu.cas.cz (MK); oschnurr@aip.de (OS); borges@on.br (MBF)
NolL of Rhizobium sp. Strain NGR234 Is Required for O-Acetyltransferase Activity
Berck, S.; Perret, X.; Quesada-Vincens, D.; Promé, J.-C.; Broughton, W. J.; Jabbouri, S.
1999-01-01
Following (iso)flavonoid induction, nodulation genes of the symbiotic nitrogen-fixing bacterium Rhizobium sp. strain NGR234 elaborate a large family of lipooligosaccharidic Nod factors (NodNGR factors). When secreted into the rhizosphere of compatible legumes, these signal molecules initiate root hair deformation and nodule development. The nonreducing glucosamine residue of NodNGR factors are N acylated, N methylated, and mono- or biscarbamoylated, while position C-6 of the reducing extremity is fucosylated. This fucose residue is normally 2-O methylated and either sulfated or acetylated. Here we present an analysis of all acetylated NodNGR factors, which clearly shows that the acetate group may occupy position C-3 or C-4 of the fucose moiety. Disruption of the flavonoid-inducible nolL gene, which is preceded by a nod box, results in the synthesis of NodNGR factors that lack the 3-O- or 4-O-acetate groups. Interestingly, the nodulation capacity of the mutant NGRΩnolL is not impaired, whereas introduction of the nod box::nolL construct into the related strain Rhizobium fredii USDA257 extends the host range of this bacterium to Calopogonium caeruleum, Leucaena leucocephala, and Lotus halophilus. Nod factors produced by a USDA257(pnolL) transconjugant were also acetylated. The nod box::nolL construct was also introduced into ANU265 (NGR234 cured of its symbiotic plasmid), along with extra copies of the nodD1 gene. When permeabilized, these cells possessed acetyltransferase activity, although crude extracts did not. PMID:9922261
Developing and teaching the virtue-ethics foundations of healthcare whistle blowing.
Faunce, Thomas
2004-10-01
Healthcare whistle blowing, despite the benefits it has brought to healthcare systems in many developed countries, remains generally regarded as a pariah activity by many of the most influential healthcare professionals and regulatory institutions. Few if any medical schools or law department health law and bioethics classes, teach whistle blowing in a formal sense. Yet without exception, public inquiries initiated by healthcare whistle blowers have validated their central allegations and demonstrated that the whistle blowers themselves were sincere in their desire to implement the fundamental virtues and principles of medical ethics, bioethics and public health law. In many jurisdictions, the law, this time remarkably in advance of professional opinion, has offered legislative protection for reasonable allegations of whistleblowers made in good faith and in the public interest concerning a substantial and imminent threat to public safety. One reason for this paradoxical position, explored here, is that healthcare whistle blowing lacks a firm virtue-based theoretical bioethical and jurisprudential foundation. The hypothesis discussed is that the lack of this bioethical and jurisprudential substrate has contributed to a situation where healthcare whistle blowing suffers in terms of institutional support due to its lack of academic legitimacy. This article commences the process of redressing this imbalance by attempting to lay the theoretical foundations for healthcare whistle blowing. As a case study, this article concludes by discussing the Personal and Professional Development course at the ANU Medical School where healthcare whistle blowing is a formal part of a virtue-based curriculum that emphasises the foundational importance of conscience. Illustrative elements of that program are discussed.
Riaz, S; Huerta-Acosta, K; Tenscher, A C; Walker, M A
2018-04-30
Pierce's disease (PD) limits the cultivation of Vitis vinifera grape cultivars in California, across the southern United States and into South America. Resistance has been well characterized in V. arizonica, and one resistance locus has been identified (PdR1). However, resistance is poorly characterized in most other grape species. We tested a wide range of Vitis species from the southwestern United States for resistance to PD and used nuclear and chloroplast markers to phenotypically and genetically select a diverse set of resistant accessions. Chloroplast SSR markers identified 11 maternal lineage lines within the set of 17 (14 new and three previously identified) PD resistant accessions. A total of 19 breeding populations (F1 and pseudo-BC1) were developed with the 14 PD resistant accessions, and a total of 705 seedlings were analyzed for PD resistance. Using a limited mapping approach, 12 SSR markers, linked to the PdR1 locus, were used to genotype the breeding populations and phenotypic data were analyzed. Nine accessions had a major resistance quantitative trait locus (QTL) within the genomic region containing PdR1. The phenotypic data for these three resistant accessions, ANU67, b41-13, and T03-16, did not associate with PdR1 linked markers, indicating that their resistance is located in other regions of the genome. These three accessions were identified as candidates for use in the development of framework maps with larger populations capable of detecting additional and unique loci for PD resistance breeding and the stacking of PD resistance genes.
Massartu: The Observation of Astronomical Phenomena in Assyria (7th Century BC)
NASA Astrophysics Data System (ADS)
Fales, F. M.
2011-06-01
The term massartu is well attested in letters in cuneiform to and from the Neo-Assyrian court, written in the main in the 7th century BC. In itself, massartu is a general Akkadian term, meaning "watch, guard", but in the early 1st millennium BC it takes on two interesting semantic specializations, both of which are tied to the practical and political needs of the Assyrian empire. In astrological-astronomical terms, massartu denotes the wake, vigil, or watch for astronomical observations on the part of the court specialists: such a wake was required by the Assyrian king on a nightly basis, for the subsequent consultation of the vast compilation of omens called Enūma Anu Enlil, and the drawing of conclusions relating to the state of the empire and of the royal dynasty. Many interesting texts show us the workings of the massartu in the capital city Nineveh or in other cities of Mesopotamia. But massartu had also a wider meaning, "vigilance", which denoted the requirement, on the part of all the subjects of the king of Assyria, to keep their eyes and ears open, so as to be able to report to the king if anything untoward was taking place, whether in the capital city or in the most remote military outpost of the empire. Thus, in a way, the astrologers were expected to perform no more and no less than the collective duty of "vigilance" on behalf of the king-but with their eyes trained on the heavens, and in await for signs ultimately sent from the gods.
On the Origin of the Wind Variability of 55 Cyg
NASA Astrophysics Data System (ADS)
Haucke, M.; Kraus, M.; Venero, R. O. J.; Tomić, S.; Cidale, L. S.; Nickeler, D. H.; Curé, M.
2014-10-01
The early B-type supergiant 55 Cygni exhibits pronounced night-to-night variations in its Hα P-Cygni line profile, probably related to a strong variable stellar wind. In this work we studied a sample of spectroscopic observations, taken at the Observatory of Ondřejov (Czech Republic), in order to analyze the variations in the stellar and wind parameters. The observations were modeled using FASTWIND code (Santolaya-Rey, Puls & Herrero 1997, A&A 323, 488-512). Although we were not able to find an exact period from the Hα line profile variations, the same pattern (shape and intensity) seems to have a cyclic behaviour of about 17 days. The values for the wind and stellar parameters suggest changes of the mass loss rate by a factor of three during a cycle of variability. On the other hand, Kraus et al. (Precision Asteroseismology Proceedings, IAU Symposium 301, 2014) found that the HeI λ 6678 photospheric absorption line presents a 1.09 day period, which could be superimposed over a longer period. From the analysis of our theoretical parameters we found that a gravitational mode of pulsation could not be the only agent responsible for the observed variations. As the stars evolving from the main sequence to the red supergiant stage (RSG) have different pulsation properties than those evolving back to the blue supergiant region (Saio, Georgy & Meynet, 2013, MNRAS, 433, 1246), we conclude that 55 Cygni could be in a post-RSG phase with multiperiodic pulsation modes. The variable mass loss could be attributed to the coupling of the oscillation modes.
Wolf, Rainer
1972-12-01
To affirm the hypothesis that during the early cleavage inWachtliella persicariae L., central and marginal ooplasm do not only differ by their kinematic aspects (Wolf, 1969; Wolf and Krause, 1971) but also physiologically, the radial symmetry of the ooplasm has been destroyed experimentally. For this purpose a device has been developed permitting a local ultrasonic treatment of insect eggs limited to well defined regions of various sizes (Fig. 1). The changes in the egg architecture can be observed directly while the treatment is going on and their effects on embryogenesis are analyzed by time-lapse motion pictures.Cleavage nuclei which have been transferred prematurely to the egg surface during low-intensity ultrasonic radiation of the whole egg length (Fig. 2 a), move back into the central ooplasm after treatment; the marginal plasm becomes populated only later at the same time as in untreated eggs. Local high-intensity ultrasonic treatment, too (Fig. 2 c), obviously does not cause any damage to the nuclei, while the ooplasm within the treated area becomes completely mixed up. After exposure the untreated region may become partially coated by a sheath of mixed up ooplasm. The populating of the egg surface by the nuclei is restricted to those sites where the untreated marginal ooplasm remains at the surface. These are the only areas for the later formation of preblastoderm and blastoderm. For the normal distribution of the cleavage energides a certain ooplasmic component sensitive to ultrasonic treatment seems to be responsible, the ultrastructure of which will be subjected to further investigations.
PREFACE: The 16th International Conference on Positron Annihilation (ICPA-16)
NASA Astrophysics Data System (ADS)
Alam, Ashraf; Coleman, Paul; Dugdale, Stephen; Roussenova, Mina
2013-06-01
The 16th International Conference on Positron Annihilation (ICPA-16) was held at the University of Bristol, United Kingdom during 19-24 August, 2012. This triennial conference is the foremost gathering of the Positron Annihilation Physics community and it was hosted in the UK for the first time since the series of meetings first started back in 1965. The University of Bristol, the Alma Mater of Paul Dirac, is situated at the heart of the city, and it has established a worldwide reputation in research and teaching. Many of the topics which were discussed during ICPA-16 form an integral part of the research themes in the schools of Physics, Chemistry and Engineering of this University. ICPA-16 attracted a diverse audience, both from academic and industrial institutions, with over 200 participants from 29 countries. It continued the long held tradition of showcasing novel research in the field of positron annihilation and a total of 170 papers were presented as talks and posters. The papers reported studies of metallic and semi-conducting solids, polymers and soft matter, porous materials, surfaces and interfaces, as well as advances in experimental, analytical and biomedical applications. The high quality of the presented work, coupled with the enthusiastic exchange of ideas, provided an invaluable forum, especially for younger researchers and postgraduate students. The excellence of student presentations was acknowledged by the award of prizes for the best student posters, which were received by David Billington (University of Bristol, UK), Moussa Sidibe (CEMHTI, France) and Hongxia Xu (Tohoku University, Japan). All papers published in the Conference Proceedings were reviewed by ICPA-16 participants. We are indebted to all reviewers who contributed their time and intellectual resources, allowing the refereeing and editing process to move smoothly toward the compilation of the Proceedings. Our sincere thanks and gratitude go to everyone who contributed to the success of the conference. We are grateful to all participants for their informative talks, poster presentations and fruitful discussions; the session chairs for keeping to the tight time schedule and for making sure the oral presentation sessions ran smoothly; Maria Dugdale for her time and effort in organising the social programme for the accompanying persons; the student volunteers from the Bristol Positron Group for all their help and time before, during and after the conference; the Bath positron group for helping with the organisation of the excursion and last, but not least, the University of Bristol Conference Office staff for their help with the organisation of the conference. We are also very grateful for the financial and logistical help from the University of Bristol and financial support from our sponsors and exhibitors, Ortec and Canberra. We conclude by wishing the Organising Committee of ICPA-17 all the best for a successful conference. We look forward to seeing everyone in China in 2015. Ashraf Alam, Paul Coleman, Stephen Dugdale and Mina Roussenova Guest Editors Bristol, April 2013 Local organising committeeInternational Advisory committee M A Alam, S Dugdale and M Roussenova P Coleman (UK, Chairman) University of Bristol, UK R Krause-Rehberg(Germany, Vice-chairman) P Coleman and S Townrow M A Alam (UK) University of Bath, UK G Laricchia (UK) M Charlton R Brusa (Italy) University of Swansea, UK M Doyama (Japan) G Laricchia B Ganguly (India) University College London, UK C Hugenschmidt (Germany) D Keeble Zs Kajcsos (Hungary, deceased) University of Dundee, UK Y Kobayashi (Japan) J Kuriplach (Czech Republic) P Mascher (Canada) A Mills (USA) Y Nagashima (Japan) Steering committee M Puska (Finland) M A Alam (UK, Secretary) H Schut (Netherlands) P Coleman (UK) A Seeger (Germany) B Ganguly (India) Y Shirai (Japan) Y Kobayashi (Japan) A Somoza (Argentina) P Mascher (Canada) A Stewart (Canada) H Schut (Netherlands) Z Tang (China) R Krause-Rehberg (Germany) A Weiss (USA) Sponsor logos Conference photograph
Applications of optical sensors for high-frequency water-quality monitoring and research
Pellerin, Brian
2015-01-01
The recent commercial availability of in-situ optical sensors, together with new techniques for data collection and analysis, provides the opportunity to monitor a wide range of water-quality constituents over time scales during which environmental conditions actually change. Traditional approaches for data collection (daily to monthly discrete samples) are often limited by high sample collection, processing, and analytical costs, difficult site access, and logistical challenges, particularly for long-term sampling at a large number of sites. Optical sensors that continuously measure constituents in the environment by absorbance or fluorescence properties (Figure 1) have had a long history of use in oceanography for measuring highly resolved concentrations and fluxes of organic matter, nutrients, and algal material. However, much of the work using commercially-available optical sensors in rivers and streams has taken place in only the last few years. Figure 1. [NOT SHOWN] Optical sensor technology is now sufficiently developed to warrant broader application for research and monitoring in coastal and freshwater systems, and the United States Geological Survey (a U.S. science agency) is now using these sensors in a variety of research and monitoring programs to better understand water quality in-situ and in real-time. Examples are numerous and range from the applications of nitrate sensors for calculating loads to estuaries susceptible to hypoxia (Pellerin et al., 2014) to the use of fluorometers to estimate methymercury fluxes (Bergamaschi et al., 2011) and disinfection byproduct formation (Carpenter et al., 2013). Transmitting these data in real-time provides information that can be used for early trend detection, help identify monitoring gaps critical for water management, and provide science-based decision support across a range of issues related to water quality, freshwater ecosystems, and human health. Despite the value of these sensors, collecting data that meet high-quality standards requires investment in and adherence to tested and established methods and protocols for sensor operation and data management (Pellerin et al., 2013). For example, optical sensor measurements can be strongly influenced by a variety of matrix effects, including water temperature, inner filtering from highly colored water, and scattering of light by suspended particles (Downing et al., 2012). Characterizing and correcting sensors for these effects – as well as the continued development of common methodologies and protocols for sensor use – will be critical to ensuring comparable measurements across sites and over time. In addition, collaborative efforts such as the Nutrient Sensor Challenge (www.nutrients-challenge.org) will continue to accelerate the development, production and use of affordable, reliable and accurate sensors for a range of environments. REFERENCES Bergamaschi .B.A., Fleck J.A., Downing B.D., Boss E., Pellerin B.A., Ganju N.K., Schoellhamer D.H., Byington A.A., Heim W.A., Stephenson M., Fujii R. (2011), Methyl mercury dynamics in a tidal wetland quantified using in situ optical measurements. Limnology and Oceanography, 56(4): 1355-1371. Carpenter K.D., Kraus T.E.C., Goldman J.H., Saraceno J., Downing B.D., Bergamaschi B.A., McGhee G., Triplett T. (2013), Sources and Characteristics of Organic Matter in the Clackamas River, Oregon, Related to the Formation of Disinfection By-products in Treated Drinking Water: U.S. Geological Survey Scientific Investigations Report 2013–5001, 78 p. Downing .B.D., Pellerin B.A., Bergamaschi B.A., Saraceno J., Kraus T.E.K. (2012), Seeing the light: The effects of particles, temperature and inner filtering on in situ CDOM fluorescence in rivers and streams. Limnology and Oceanography: Methods, 10: 767-775. Pellerin B.A., Bergamaschi B.A., Downing B.D., Saraceno J., Garrett J.D., Olsen L.D. (2013), Optical Techniques for the Determination of Nitrate in En
Edgar, N. Terence; Cecil, C. Blaine; Mattick, R.E.; de Deckker, Patrick; Djajadihardja, Yusuf S.
2003-01-01
The Gulf of Carpentaria is a tropical, silled epicontinental sea and may be a modern analogue for ancient cratonic basins. For the purpose of this study, the Gulf of Carpentaria is compared to Pennsylvanian cratonic basins of the United States. During the Pennsylvanian, the North American continent moved from the Southern Hemisphere, through the Equator, into the Northern Hemisphere. Today, the Gulf of Carpentaria–New Guinea region is a few degrees south of the Equator and is moving towards it. During the Pennsylvanian, the world was subjected to major glaciations and associated sea-level changes. The island of New Guinea and the Gulf of Carpentaria have undergone similar processes during the Quaternary. A reconnaissance seismic survey of the gulf conducted by the USGS and the Australian National University (ANU), combined with oil-exploration well data, provided the first step in a systematic evaluation of a modern tropical epicontinental system. During the Cenozoic, the region was dominated by terrestrial sedimentation in a temperate climate. At the same time, carbonates were being deposited on the northern shelf edge of the Australian Plate. During the Miocene, carbonate deposition expanded southward into the gulf region. Then in the Late Miocene, carbonate sedimentation was replaced by terrigenous clastics derived from the developing Central Range of the island of New Guinea, which developed a wetter climate while moving northwards into the tropics. At least 14 basin-wide transgressive–regressive cycles are identified by channels that were eroded under subaerial conditions since about the Miocene. Comparison of the modern Gulf of Carpentaria sequences with those of the Pennsylvanian reveals many similarities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomas, Adam D.; Dopita, Michael A.; Davies, Rebecca
We present the second and final data release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). Data are presented for 63 new galaxies not included in the first data release, and we provide 2D emission-line fitting products for the full S7 sample of 131 galaxies. The S7 uses the WiFeS instrument on the ANU 2.3 m telescope to obtain spectra with a spectral resolution of R = 7000 in the red (540–700 nm) and R = 3000 in the blue (350–570 nm), over an integral field of 25 × 38 arcsec{sup 2} with 1 × 1 arcsec{sup 2} spatial pixels. The S7 contains bothmore » the largest sample of active galaxies and the highest spectral resolution of any comparable integral field survey to date. The emission-line fitting products include line fluxes, velocities, and velocity dispersions across the WiFeS field of view, and an artificial neural network has been used to determine the optimal number of Gaussian kinematic components for emission-lines in each spaxel. Broad Balmer lines are subtracted from the spectra of nuclear spatial pixels in Seyfert 1 galaxies before fitting the narrow lines. We bin nuclear spectra and measure reddening-corrected nuclear fluxes of strong narrow lines for each galaxy. The nuclear spectra are classified on optical diagnostic diagrams, where the strength of the coronal line [Fe vii] λ 6087 is shown to be correlated with [O iii]/H β . Maps revealing gas excitation and kinematics are included for the entire sample, and we provide notes on the newly observed objects.« less
2010-01-01
Background Recent projections suggest that by the year 2030 depression will be the primary cause of disease burden among developed countries. Delivery of accessible consumer-focused evidenced-based services may be an important element in reducing this burden. Many consumers report a preference for self-help modes of delivery. The Internet offers a promising modality for delivering such services and there is now evidence that automated professionally developed self-help psychological interventions can be effective. By contrast, despite their popularity, there is little evidence as to the effectiveness of Internet support groups which provide peer-to-peer mutual support. Methods/Design Members of the community with elevated psychological distress were randomised to receive one of the following: (1) Internet Support Group (ISG) intervention, (2) a multi-module automated psychoeducational and skills Internet Training Program (ITP), (3) a combination of the ISG and ITP, or (4) an Internet Attention Control website (IAC) comprising health and wellbeing information and question and answer modules. Each intervention was 12 weeks long. Assessments were conducted at baseline, post-intervention, 6 and 12 months to examine depressive symptoms, social support, self-esteem, quality of life, depression literacy, stigma and help-seeking for depression. Participants were recruited through a screening postal survey sent to 70,000 Australians aged 18 to 65 years randomly selected from four rural and four metropolitan regions in Australia. Discussion To our knowledge this study is the first randomised controlled trial of the effectiveness of a depression ISG. Trial registration Current Controlled Trials ISRCTN65657330. PMID:20211025
Biofuels in transport sector of Latvia: experience, current status and barriers
NASA Astrophysics Data System (ADS)
Smigins, R.; Shipkovs, P.
2014-02-01
During the last 10 years biofuel production and utilization in the European Union have become more extensive owing to support provided by the relevant EU Directives. Achievement of the main targets defined by Directives was not simple, being confronted with various barriers. Latvia is one of the EU member-countries that have set an ambitious goal as to the production of biofuel and its use in transport. The authors summarize the major achievements of the country in this area and analyze the main barriers to implementation of biofuels in the transport sector, providing an outlook on the current status of the bioenergy and the transport situation in Latvia. Pēdējo 10 gadu laikā biodegvielu ražošana un izmantošana ES ir kļuvusi daudz plašāka, pateicoties spēcīgam Direktīvu atbalstam. Galveno Direktīvu definēto mērķu sasniegšana nebija viegla un saskārās ar dažādiem sarežģījumiem. Latvija ir viena no ES valstīm, kas uzstādīja ambiciozu mērķi biodegvielu ražošanā un tālākā šīs degvielas izmantošanā transportā. Dotais raksts dod ieskatu galvenajos valsts sasniegumos šajā sfērā, kā arī analizē galvenās barjeras, kas traucē biodegvielu ieviešanu transporta sektorā. Tāpat tiek dots ieskats uz valsts esošo situāciju enerģētikā un transportā.
Basin seismology in the megacity of Jakarta, Indonesia
NASA Astrophysics Data System (ADS)
Widiyantoro, S.; Cummins, P. R.; Saygin, E.; Cipta, A.; Ridwan, M.; Joshi, N.; Murjaya, J.; Irsyam, M.
2016-12-01
Like several of SE Asia's megacities, Jakarta is home to a very large and vulnerable urban population (10 million in the city itself, 28 million in greater Jakarta). Jakarta also has many tall buildings built on a basin filled with poorly consolidated sediments. The resonant periods of many buildings are longer than 1 second, and if these periods match the resonant periods of the sedimentary basin, they may be particularly prone to damage if a large earthquake occurs. In order to characterize the subsurface structure of the Jakarta Basin, a dense portable seismic broad-band network was operated by the Australian National University (ANU) and the Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG) between October 2013 and February 2014. Overall 96 locations were sampled through successive deployments of 52 seismic broadband sensors at different parts of the city. Oceanic and anthropogenic noise was recorded as well as regional and teleseismic earthquakes. We applied a Trans-dimensional Bayesian implementation of Ambient Noise Tomography to estimate the thickness and shear velocity of the basin fill. Results show that these vary between about 300 to 700 meters and 200 to 1200 m/s, respectively. We show that these variations agree well with variations in P-wave arrival time delays of regional and distant earthquakes, variations in the peak period of horizontal-over-vertical spectral ratios, and times of P-to-S converted waves generated at the floor of the basin. We discuss the implications these low seismic velocities and the thick basin beneath the city may have for seismic amplification during a subduction megathrust or other large earthquake close to the city of Jakarta.
The Earth System Grid Federation (ESGF) Project
NASA Astrophysics Data System (ADS)
Carenton-Madiec, Nicolas; Denvil, Sébastien; Greenslade, Mark
2015-04-01
The Earth System Grid Federation (ESGF) Peer-to-Peer (P2P) enterprise system is a collaboration that develops, deploys and maintains software infrastructure for the management, dissemination, and analysis of model output and observational data. ESGF's primary goal is to facilitate advancements in Earth System Science. It is an interagency and international effort led by the US Department of Energy (DOE), and co-funded by National Aeronautics and Space Administration (NASA), National Oceanic and Atmospheric Administration (NOAA), National Science Foundation (NSF), Infrastructure for the European Network of Earth System Modelling (IS-ENES) and international laboratories such as the Max Planck Institute for Meteorology (MPI-M) german Climate Computing Centre (DKRZ), the Australian National University (ANU) National Computational Infrastructure (NCI), Institut Pierre-Simon Laplace (IPSL), and the British Atmospheric Data Center (BADC). Its main mission is to support current CMIP5 activities and prepare for future assesments. The ESGF architecture is based on a system of autonomous and distributed nodes, which interoperate through common acceptance of federation protocols and trust agreements. Data is stored at multiple nodes around the world, and served through local data and metadata services. Nodes exchange information about their data holdings and services, trust each other for registering users and establishing access control decisions. The net result is that a user can use a web browser, connect to any node, and seamlessly find and access data throughout the federation. This type of collaborative working organization and distributed architecture context en-lighted the need of integration and testing processes definition to ensure the quality of software releases and interoperability. This presentation will introduce the ESGF project and demonstrate the range of tools and processes that have been set up to support release management activities.
NASA Astrophysics Data System (ADS)
Thomas, Adam D.; Dopita, Michael A.; Shastri, Prajval; Davies, Rebecca; Hampton, Elise; Kewley, Lisa; Banfield, Julie; Groves, Brent; James, Bethan L.; Jin, Chichuan; Juneau, Stéphanie; Kharb, Preeti; Sairam, Lalitha; Scharwächter, Julia; Shalima, P.; Sundar, M. N.; Sutherland, Ralph; Zaw, Ingyin
2017-09-01
We present the second and final data release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). Data are presented for 63 new galaxies not included in the first data release, and we provide 2D emission-line fitting products for the full S7 sample of 131 galaxies. The S7 uses the WiFeS instrument on the ANU 2.3 m telescope to obtain spectra with a spectral resolution of R = 7000 in the red (540-700 nm) and R = 3000 in the blue (350-570 nm), over an integral field of 25 × 38 arcsec2 with 1 × 1 arcsec2 spatial pixels. The S7 contains both the largest sample of active galaxies and the highest spectral resolution of any comparable integral field survey to date. The emission-line fitting products include line fluxes, velocities, and velocity dispersions across the WiFeS field of view, and an artificial neural network has been used to determine the optimal number of Gaussian kinematic components for emission-lines in each spaxel. Broad Balmer lines are subtracted from the spectra of nuclear spatial pixels in Seyfert 1 galaxies before fitting the narrow lines. We bin nuclear spectra and measure reddening-corrected nuclear fluxes of strong narrow lines for each galaxy. The nuclear spectra are classified on optical diagnostic diagrams, where the strength of the coronal line [Fe vii] λ6087 is shown to be correlated with [O III]/Hβ. Maps revealing gas excitation and kinematics are included for the entire sample, and we provide notes on the newly observed objects.
Climate Science's Globally Distributed Infrastructure
NASA Astrophysics Data System (ADS)
Williams, D. N.
2016-12-01
The Earth System Grid Federation (ESGF) is primarily funded by the Department of Energy's (DOE's) Office of Science (the Office of Biological and Environmental Research [BER] Climate Data Informatics Program and the Office of Advanced Scientific Computing Research Next Generation Network for Science Program), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), and the National Science Foundation (NSF), the European Infrastructure for the European Network for Earth System Modeling (IS-ENES), and the Australian National University (ANU). Support also comes from other U.S. federal and international agencies. The federation works across multiple worldwide data centers and spans seven international network organizations to provide users with the ability to access, analyze, and visualize data using a globally federated collection of networks, computers, and software. Its architecture employs a series of geographically distributed peer nodes that are independently administered and united by common federation protocols and application programming interfaces (APIs). The full ESGF infrastructure has now been adopted by multiple Earth science projects and allows access to petabytes of geophysical data, including the Coupled Model Intercomparison Project (CMIP; output used by the Intergovernmental Panel on Climate Change assessment reports), multiple model intercomparison projects (MIPs; endorsed by the World Climate Research Programme [WCRP]), and the Accelerated Climate Modeling for Energy (ACME; ESGF is included in the overarching ACME workflow process to store model output). ESGF is a successful example of integration of disparate open-source technologies into a cohesive functional system that serves the needs the global climate science community. Data served by ESGF includes not only model output but also observational data from satellites and instruments, reanalysis, and generated images.
A large-format imager for the SkyMapper Survey Telescope
NASA Astrophysics Data System (ADS)
Granlund, A.; Conroy, P. G.; Keller, S. C.; Oates, A. P.; Schmidt, B.; Waterson, M. F.; Kowald, E.; Dawson, M. I.
2006-06-01
The Research School of Astronomy and Astrophysics (RSAA) of the Australian National University (ANU) at Mt Stromlo Observatory is developing a wide-field Cassegrain Imager for the new 1.3m SkyMapper Survey Telescope under construction for Siding Spring Observatory, NSW, Australia. The Imager features a fast-readout, low-noise 268 Million pixel CCD mosaic that provides a 5.7 square degree field of view. Given the close relative sizes of the telescope and Imager, the work is proceeding in close collaboration with the telescope's manufacturer, Electro Optics Systems Pty Ltd (Canberra, Australia). The design of the SkyMapper Imager focal plane is based on E2V (Chelmsford, UK) deep depletion CCDs. These devices have 2048 x 4096 15 micron pixels, and provide a 91% filling factor in our mosaic configuration of 4 x 8 chips. In addition, the devices have excellent quantum efficiency from 300nm-950nm, near perfect cosmetics, and low-read noise, making them well suited to the all-sky ultraviolet through near-IR Southern Sky Survey to be conducted by the telescope. The array will be controlled using modified versions of the new IOTA controllers being developed for Pan-STARRS by Onaka and Tonry et al. These controllers provide a cost effective, low-volume, high speed solution for our detector read-out requirements. The system will have an integrated 6-filter exchanger, and Shack-Hartmann optics, and will be cooled by closed-cycle helium coolers. This paper will present the specifications, and opto-mechanical and detector control design of the SkyMapper Imager, including the test results of the detector characterisation and manufacturing progress.
Randolph, R.B.; Krause, R.E.
1984-01-01
A two-dimensional finite-difference model of the principal artesian aquifer in the Savannah, Georgia, area, originally developed by Counts and Krause (1976), has been expanded and refined. The model was updated and the grid redesigned to provide more current and accurate detail for ground-water resources management alternatives. Improvements in the definition of the flow system were made possible by the acquisition of additional data in the area and by recently completed regional models that include the area. The model was initially calibrated by using the estimated predevelopment potentiometric surface of 1880. The flow system under predevelopment conditions was sluggish and only 100 cubic feet per second (65 million gallons per day) flowed through the model area. It was then tested for acceptance by using the May 1980 potentiometric surface and corresponding pumping stress of approximately 85 million gallons per day in the Savannah, Georgia-Hilton Head Island, South Carolina, area. The flow through the system under 1980 conditions was about 390 cubic feet per second (250 million gallons per day) and the vertical inflow from the overlying surficial aquifer more than doubled due to formerly rejected recharge that now flows vertically into the aquifer. Calibration was accurate + or - 10 feet. The absolute error per node was 3.4 feet. A hypothetical 25-percent increase in pumpage over the entire area was used to represent a gradual growth in commercial and municipal pumpage over the next 20 to 30 years. The increase produced a maximum decline of 30 feet below the existing water level of 135 feet below sea level at the center of the cone of depression in Savannah, and a 5-foot decline at a radius of 20 miles from the center of the cone of depression. (USGS)
Relativistic and noise effects on multiplayer Prisoners' dilemma with entangling initial states
NASA Astrophysics Data System (ADS)
Goudarzi, H.; Rashidi, S. S.
2017-11-01
Three-players Prisoners' dilemma (Alice, Bob and Colin) is studied in the presence of a single collective environment effect as a noise. The environmental effect is coupled with final states by a particular form of Kraus operators K_0 and K_1 through amplitude damping channel. We introduce the decoherence parameter 0≤p≤1 to the corresponding noise matrices, in order to controling the rate of environment influence on payoff of each players. Also, we consider the Unruh effect on the payoff of player, who is located at a noninertial frame. We suppose that two players (Bob and Colin) are in Rindler region I from Minkowski space-time, and move with same uniform acceleration (r_b=r_c) and frequency mode. The game is begun with the classical strategies cooperation ( C) and defection ( D) accessible to each player. Furthermore, the players are allowed to access the quantum strategic space ( Q and M). The quantum entanglement is coupled with initial classical states by the parameter γ \\in [0,π /2]. Using entangled initial states by exerting an unitary operator \\hat{J} as entangling gate, the quantum game (competition between Prisoners, as a three-qubit system) is started by choosing the strategies from classical or quantum strategic space. Arbitrarily chosen strategy by each player can lead to achieving profiles, which can be considered as Nash equilibrium or Pareto optimal. It is shown that in the presence of noise effect, choosing quantum strategy Q results in a winning payoff against the classical strategy D and, for example, the strategy profile ( Q, D, C) is Pareto optimal. We find that the unfair miracle move of Eisert from quantum strategic space is an effective strategy for accelerated players in decoherence mode (p=1) of the game.
Direct Detection of C_2H_2 in Air and Human Breath by Cw-Crds
NASA Astrophysics Data System (ADS)
Schmidt, Florian M.; Vaittinen, Olavi; Metsälä, Markus; Halonen, Lauri
2010-06-01
Continuous wave cavity ring-down spectroscopy (cw-CRDS) is an established cavity-enhanced absorption technique that can provide the necessary sensitivity, selectivity and fast acquisition time for many applications involving the detection of trace species. We present a simple but highly sensitive cw-CRDS spectrometer based on an external cavity diode laser operating in the near-infrared region. This instrument allows us to directly detect acetylene (C_2H_2) mixing ratios in air with a detection limit of 120 parts per trillion by volume (pptv) measuring on a C_2H_2 absorption line at 6565.620 cm-1. Acetylene is a combustion product that is routinely used in environmental monitoring as a marker for anthropogenic emissions. In a recent work, the spectrometer was employed to measure the level of acetylene in indoor and outdoor air in Helsinki. Continuous flow measurements with high time resolution (one minute) revealed strong fluctuations in the acetylene mixing ratio in outdoor air during daytime. Due to its non-invasive nature and fast response time, the analysis of exhaled breath for medical diagnostics is an excellent and straightforward alternative to methods using urine or blood samples. In an ongoing study, the cw-CRDS instrument is used to establish the baseline level of acetylene in the breath of the healthy population. An elevated amount of acetylene in breath could indicate exposure to combustion exhausts or other volatile organic compound (VOC) rich sources. The latest results of this investigation will be presented. F. M. Schmidt, O. Vaittinen, M. Metsälä, P. Kraus and L. Halonen, submitted for publication in Appl. Phys. B.
Thievessen, Ingo; Fakhri, Nikta; Steinwachs, Julian; Kraus, Viola; McIsaac, R. Scott; Gao, Liang; Chen, Bi-Chang; Baird, Michelle A.; Davidson, Michael W.; Betzig, Eric; Oldenbourg, Rudolf; Waterman, Clare M.; Fabry, Ben
2015-01-01
Vinculin is filamentous (F)-actin-binding protein enriched in integrin-based adhesions to the extracellular matrix (ECM). Whereas studies in 2-dimensional (2D) tissue culture models have suggested that vinculin negatively regulates cell migration by promoting cytoskeleton–ECM coupling to strengthen and stabilize adhesions, its role in regulating cell migration in more physiologic, 3-dimensional (3D) environments is unclear. To address the role of vinculin in 3D cell migration, we analyzed the morphodynamics, migration, and ECM remodeling of primary murine embryonic fibroblasts (MEFs) with cre/loxP-mediated vinculin gene disruption in 3D collagen I cultures. We found that vinculin promoted 3D cell migration by increasing directional persistence. Vinculin was necessary for persistent cell protrusion, cell elongation, and stable cell orientation in 3D collagen, but was dispensable for lamellipodia formation, suggesting that vinculin-mediated cell adhesion to the ECM is needed to convert actin-based cell protrusion into persistent cell shape change and migration. Consistent with this finding, vinculin was necessary for efficient traction force generation in 3D collagen without affecting myosin II activity and promoted 3D collagen fiber alignment and macroscopical gel contraction. Our results suggest that vinculin promotes directionally persistent cell migration and tension-dependent ECM remodeling in complex 3D environments by increasing cell–ECM adhesion and traction force generation.—Thievessen, I., Fakhri, N., Steinwachs, J., Kraus, V., McIsaac, R. S., Gao, L., Chen, B.-C., Baird, M. A., Davidson, M. W., Betzig, E., Oldenbourg, R., Waterman, C., M., Fabry, B. Vinculin is required for cell polarization, migration, and extracellular matrix remodeling in 3D collagen. PMID:26195589
From the Beginning: Archiving the History of NRAO and US Radio Astronomy
NASA Astrophysics Data System (ADS)
Bouton, E. N.
2005-12-01
In 2006 the National Radio Astronomy Observatory will celebrate its 50th anniversary. Before 2003, there were neither archives nor a formal archiving program at NRAO; institutional records were located at any of the four NRAO sites in four different states, and there was no record of the materials that we had. In mid-2003, the long-time NRAO librarian retired and began part time work as NRAO's first archivist. With the completion of an addition to the headquarters building in Charlottesville in spring 2005, the fledgling NRAO Archives moved into a new 1400 sq ft space. In addition to NRAO materials, the Archives also collects papers of individuals. Grote Reber, who built the first radio telescope in his backyard in Wheaton IL in 1937, had in 1995, donated many of his personal papers to NRAO, and these papers have been indexed and are available to researchers. We continue to receive additional materials from his estate in Tasmania. The complete papers of John Kraus, author, researcher, and professor in radio astronomy and engineering at Ohio State University for many years, were donated to the NRAO Archives by his son and estate executor in spring 2005. The NRAO Archives has also mounted Web resources with texts written by Nan Dieter Conklin and by Doc Ewen describing their work in the developing years of US radio astronomy. This talk will present the highlights of how, on a limited budget but with broad support of NRAO staff, the NRAO Archives has begun a program to gather and organize materials on institutional history as well as the personal papers and recollections of contributors to US radio astronomy history.
Positive contraction mappings for classical and quantum Schrödinger systems
NASA Astrophysics Data System (ADS)
Georgiou, Tryphon T.; Pavon, Michele
2015-03-01
The classical Schrödinger bridge seeks the most likely probability law for a diffusion process, in path space, that matches marginals at two end points in time; the likelihood is quantified by the relative entropy between the sought law and a prior. Jamison proved that the new law is obtained through a multiplicative functional transformation of the prior. This transformation is characterised by an automorphism on the space of endpoints probability measures, which has been studied by Fortet, Beurling, and others. A similar question can be raised for processes evolving in a discrete time and space as well as for processes defined over non-commutative probability spaces. The present paper builds on earlier work by Pavon and Ticozzi and begins by establishing solutions to Schrödinger systems for Markov chains. Our approach is based on the Hilbert metric and shows that the solution to the Schrödinger bridge is provided by the fixed point of a contractive map. We approach, in a similar manner, the steering of a quantum system across a quantum channel. We are able to establish existence of quantum transitions that are multiplicative functional transformations of a given Kraus map for the cases where the marginals are either uniform or pure states. As in the Markov chain case, and for uniform density matrices, the solution of the quantum bridge can be constructed from the fixed point of a certain contractive map. For arbitrary marginal densities, extensive numerical simulations indicate that iteration of a similar map leads to fixed points from which we can construct a quantum bridge. For this general case, however, a proof of convergence remains elusive.
Patterns in Patient Access and Utilization of Online Medical Records: Analysis of MyChart.
Redelmeier, Donald A; Kraus, Nicole C
2018-02-06
Electronic patient portals provide a new method for sharing personal medical information with individual patients. Our aim was to review utilization patterns of the largest online patient portal in Canada's largest city. We conducted a 4-year time-trend analysis of aggregated anonymous utilization data of the MyChart patient portal at Sunnybrook Health Sciences Centre in Ontario, Canada, from January 1, 2012, through December 31, 2015. Prespecified analyses examined trends related to day (weekend vs weekday), season (July vs January), year (2012 vs 2015), and an extreme adverse weather event (ice storm of December 20-26, 2013). Primary endpoints included three measures of patient portal activity: registrations, logins, and pageviews. We identified 32,325 patients who registered for a MyChart account during the study interval. Time-trend analysis showed no sign of attenuating registrations over time. Logins were frequent, averaged 734 total per day, and showed an increasing trend over time. Pageviews mirrored logins, averaged about 3029 total per day, and equated to about 5 pageviews during the average login. The most popular pageviews were clinical notes, followed by laboratory results and medical imaging reports. All measures of patient activity were lower on weekends compared to weekdays (P<.001) yet showed no significant changes related to seasons or extreme weather. No major security breach, malware attack, or software failure occurred during the study. Online patient portals can provide a popular and reliable system for distributing personal medical information to active patients and may merit consideration for hospitals. ©Donald A Redelmeier, Nicole C Kraus. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 06.02.2018.
Searching for evidence of hydrothermal activity at Apollinaris Mons, Mars
El Maarry, M.R.; Dohm, J.M.; Marzo, G.A.; Fergason, R.; Goetz, W.; Heggy, E.; Pack, A.; Markiewicz, W.J.
2012-01-01
A multidisciplinary approach involving various remote sensing instruments is used to investigate Apollinaris Mons, a prominent volcano on Mars, as well as the surrounding plains for signs of prolonged hydrologic and volcanic, and possibly hydrothermal activity. The main findings include (1) evidence from laser altimetry indicating the large thickness (1.5-2. km at some locations) of the fan deposits draping the southern flank contrary to previous estimates, coupled with possible layering which point to a significant emplacement phase at Apollinaris Mons, (2) corroboration of Robinson et al. (Robinson, M.S., Mouginis-Mark, P.J., Zimbelman, J.R., Wu, S.S.C., Ablin, K.K., Howington-Kraus, A.E. [1993]. Icarus 104, 301-323) hypothesis regarding the formation of incised valleys on the western flanks by density current erosion which would indicate magma-water interaction or, alternatively, volatile-rich magmas early in the volcano's history, (3) mounds of diverse geometric shapes, many of which display summit depressions and occur among faults and fractures, possibly marking venting, (4) strong indicators on the flanks of the volcano for lahar events, and possibly, a caldera lake, (5) ubiquitous presence of impact craters displaying fluidized ejecta in both shield-forming (flank and caldera) materials and materials that surround the volcano that are indicative of water-rich target materials at the time of impact, (6) long-term complex association in time among shield-forming materials and Medusae Fossae Formation.The findings point to a site of extensive volcanic and hydrologic activity with possibly a period of magma-water interaction and hydrothermal activity. Finally, we propose that the mound structures around Apollinaris should be prime targets for further in situ exploration and search for possible exobiological signatures. ?? 2011 Elsevier Inc..
Searching for evidence of hydrothermal activity at Apollinaris Mons, Mars
El Maarry, M. Ramy; Dohm, James M.; Marzo, Giuseppe A.; Fergason, Robin; Goetz, Walter; Heggy, Essam; Pack, Andreas; Markiewicz, Wojciech J.
2012-01-01
A multidisciplinary approach involving various remote sensing instruments is used to investigate Apollinaris Mons, a prominent volcano on Mars, as well as the surrounding plains for signs of prolonged hydrologic and volcanic, and possibly hydrothermal activity. The main findings include (1) evidence from laser altimetry indicating the large thickness (1.5–2 km at some locations) of the fan deposits draping the southern flank contrary to previous estimates, coupled with possible layering which point to a significant emplacement phase at Apollinaris Mons, (2) corroboration of Robinson et al. (Robinson, M.S., Mouginis-Mark, P.J., Zimbelman, J.R., Wu, S.S.C., Ablin, K.K., Howington-Kraus, A.E. [1993]. Icarus 104, 301–323) hypothesis regarding the formation of incised valleys on the western flanks by density current erosion which would indicate magma–water interaction or, alternatively, volatile-rich magmas early in the volcano’s history, (3) mounds of diverse geometric shapes, many of which display summit depressions and occur among faults and fractures, possibly marking venting, (4) strong indicators on the flanks of the volcano for lahar events, and possibly, a caldera lake, (5) ubiquitous presence of impact craters displaying fluidized ejecta in both shield-forming (flank and caldera) materials and materials that surround the volcano that are indicative of water-rich target materials at the time of impact, (6) long-term complex association in time among shield-forming materials and Medusae Fossae Formation. The findings point to a site of extensive volcanic and hydrologic activity with possibly a period of magma–water interaction and hydrothermal activity. Finally, we propose that the mound structures around Apollinaris should be prime targets for further in situ exploration and search for possible exobiological signatures.
Under-ice melt ponds and the oceanic mixed layer
NASA Astrophysics Data System (ADS)
Flocco, D.; Smith, N.; Feltham, D. L.
2017-12-01
Under-ice melt ponds are pools of freshwater beneath the Arctic sea ice that form when melt from the surface of the sea ice percolates down through the porous sea ice. Through double diffusion, a sheet of ice can form at the interface between the ocean and the under-ice melt pond, completely isolating the pond from the mixed layer below and forming a false bottom to the sea ice. As such, they insulate the sea ice from the ocean below. It has been estimated that these ponds could cover between 5 and 40 % of the base of the Arctic sea ice, and so could have a notable impact on the mass balance of the sea ice. We have developed a one-dimensional model to calculate the thickness and thermodynamic properties of a slab of sea ice, an under-ice melt pond, and a false bottom, as these layers evolve. Through carrying out sensitivity studies, we have identified a number of interesting ways that under-ice melt ponds affect the ice above them and the rate of basal ablation. We found that they result in thicker sea ice above them, due to their insulation of the ice, and have found a possible positive feedback cycle in which less ice will be gained due to under-ice melt ponds as the Arctic becomes warmer. More recently, we have coupled this model to a simple Kraus-Turner type model of the oceanic mixed layer to investigate how these ponds affect the ocean water beneath them. Through altering basal ablation rates and ice thickness, they change the fresh water and salt fluxes into the mixed layer, as well as incoming radiation. Multi-year simulations have, in particular, shown how these effects work on longer time-scales.
Acoustic properties of naturally produced clear speech at normal speaking rates
NASA Astrophysics Data System (ADS)
Krause, Jean C.; Braida, Louis D.
2004-01-01
Sentences spoken ``clearly'' are significantly more intelligible than those spoken ``conversationally'' for hearing-impaired listeners in a variety of backgrounds [Picheny et al., J. Speech Hear. Res. 28, 96-103 (1985); Uchanski et al., ibid. 39, 494-509 (1996); Payton et al., J. Acoust. Soc. Am. 95, 1581-1592 (1994)]. While producing clear speech, however, talkers often reduce their speaking rate significantly [Picheny et al., J. Speech Hear. Res. 29, 434-446 (1986); Uchanski et al., ibid. 39, 494-509 (1996)]. Yet speaking slowly is not solely responsible for the intelligibility benefit of clear speech (over conversational speech), since a recent study [Krause and Braida, J. Acoust. Soc. Am. 112, 2165-2172 (2002)] showed that talkers can produce clear speech at normal rates with training. This finding suggests that clear speech has inherent acoustic properties, independent of rate, that contribute to improved intelligibility. Identifying these acoustic properties could lead to improved signal processing schemes for hearing aids. To gain insight into these acoustical properties, conversational and clear speech produced at normal speaking rates were analyzed at three levels of detail (global, phonological, and phonetic). Although results suggest that talkers may have employed different strategies to achieve clear speech at normal rates, two global-level properties were identified that appear likely to be linked to the improvements in intelligibility provided by clear/normal speech: increased energy in the 1000-3000-Hz range of long-term spectra and increased modulation depth of low frequency modulations of the intensity envelope. Other phonological and phonetic differences associated with clear/normal speech include changes in (1) frequency of stop burst releases, (2) VOT of word-initial voiceless stop consonants, and (3) short-term vowel spectra.
Christensen, H; Nicklas, W; Bisgaard, M
2014-11-01
Eleven strains from hamster of Bisgaard taxa 23 and 24, also referred to as Krause's groups 2 and 1, respectively, were investigated by a polyphasic approach including data published previously. Strains showed small, regular and circular colonies with smooth and shiny appearance, typical of members of the family Pasteurellaceae. The strains formed two monophyletic groups based on 16S rRNA gene sequence comparison to other members of the family Pasteurellaceae. Partial rpoB sequencing as well as published data on DNA-DNA hybridization showed high genotypic relationships within both groups. Menaquinone 7 (MK7) was found in strains of both groups as well as an unknown ubiquinone with shorter chain length than previously reported for any other member of the family Pasteurellaceae. A new genus with one species, Mesocricetibacter intestinalis gen. nov., sp. nov., is proposed to accommodate members of taxon 24 of Bisgaard whereas members of taxon 23 of Bisgaard are proposed to represent Cricetibacter osteomyelitidis gen. nov., sp. nov. Major fatty acids of type strains of type species of both genera are C(14:0), C(14:0) 3-OH/iso-C(16:1) I, C(16:1)ω7c and C(16:0). The two genera are clearly separated by phenotype from each other and from existing genera of the family Pasteurellaceae. The type strain of Mesocricetibacter intestinalis is HIM 933/7(T) ( =Kunstyr 246/85(T) =CCUG 28030(T) =DSM 28403(T)) while the type strain of Cricetibacter osteomyelitidis is HIM943/7(T) ( =Kunstyr 507/85(T) =CCUG 36451(T) =DSM 28404(T)). © 2014 IUMS.
Campbell, Ian G.; Kraus, Amanda M.; Burright, Christopher S.; Feinberg, Irwin
2016-01-01
Study Objectives: School night total sleep time decreases across adolescence (9–18 years) by 10 min/year. This decline is comprised entirely of a selective decrease in NREM sleep; REM sleep actually increases slightly. Decreasing sleep duration across adolescence is often attributed to insufficient time in bed. Here we tested whether sleep restriction in early adolescence produces the same sleep stage changes observed on school nights across adolescence. Methods: All-night sleep EEG was recorded in 76 children ranging in age from 9.9 to 14.0 years. Each participant kept 3 different sleep schedules that consisted of 3 nights of 8.5 h in bed followed by 4 nights of either 7, 8.5, or 10 h in bed. Sleep stage durations and NREM delta EEG activity were compared across the 3 time in bed conditions. Results: Shortening time in bed from 10 to 7 hours reduced sleep duration by approximately 2 hours, roughly equal to the decrease in sleep duration we recorded longitudinally across adolescence. However, sleep restriction significantly reduced both NREM (by 83 min) and REM (by 47 min) sleep. Sleep restriction did not affect NREM delta EEG activity. Conclusions: Our findings suggest that the selective NREM reduction and the small increase in REM we observed longitudinally across 9–18 years are not produced by sleep restriction. We hypothesize that the selective NREM decline reflects adolescent brain maturation (synaptic elimination) that reduces the need for the restorative processes of NREM sleep. Citation: Campbell IG, Kraus AM, Burright CS, Feinberg I. Restricting time in bed in early adolescence reduces both NREM and REM sleep but does not increase slow wave EEG. SLEEP 2016;39(9):1663–1670. PMID:27397569
The sudden appearance of CO emission in LHA 115-S 65
NASA Astrophysics Data System (ADS)
Oksala, M. E.; Kraus, M.; Arias, M. L.; Borges Fernandes, M.; Cidale, L.; Muratore, M. F.; Curé, M.
2012-10-01
Molecular emission has been detected in several Magellanic Cloud B[e] supergiants. In this Letter, we report on the detection of CO band head emission in the B[e] supergiant LHA 115-S 65, and present a K-band near-infrared spectrum obtained with the Spectrograph for INtegral Field Observation in the Near-Infrared (SINFONI; R= 4500) on the ESO VLT UT4 telescope. The observed molecular band head emission in S65 is quite surprising in the light of a previous non-detection by McGregor, Hyland & McGinn, as well as a high-resolution (R= 50 000) Gemini/Phoenix spectrum of this star taken nine months earlier showing no emission. Based on analysis of the optical spectrum by Kraus, Borges Fernandes & de Araújo, we suspect that the sudden appearance of molecular emission could be due to density build-up in an outflowing viscous disc, as seen for Be stars. This new discovery, combined with variability in two other similar evolved massive stars, indicates an evolutionary link between B[e] supergiants and luminous blue variables. Based on observations obtained with ESO telescopes at the La Silla Paranal Observatory under programme ID 088.D-044 and at the Gemini Observatory which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (USA), the Science and Technology Facilities Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), under programme ID GS-2010B-Q-31.
Hering, K G; Tuengerthal, S; Kraus, T
2004-05-01
High resolution computed tomography (HRCT) plays an indispensable role in the diagnosis of pneumoconiosis and other lung damage arising from inhalation. Till now, however, there has been no agreed standardized convention for the use of the technique, or for documenting results uniformly. A task-group on Diagnostic Radiology in Occupational and Environmental Diseases of the German Radiological Society has produced a coding sheet based on experience gained in production of consultants' clinical reports, experts' examinations of patients seeking compensation for occupational lung disease, and physicians' professional development courses. The coding sheet has been used in a national multicenter study. It has been further developed and tested by an international working group comprising experts from Belgium (P.A. Gevenois), Germany (K.G. Hering, T. Kraus, S. Tuengerthal), Finland (L. Kivisaari, T. Vehmas), France (M. Letourneux), Great Britain (M.D. Crane), Japan (H. Arikawa, Y. Kusaka, N. Suganuma), and the USA (J. Parker). The intention is to standardize documentation of computertomographic findings in occupationally and environmentally related lung and pleural changes, and to facilitate international comparisons of results. Such comparisons were found to be achievable reproducibly with the help of CT/HRCT reference films. The classification scheme is purely descriptive (rather than diagnostic), so that all aspects of occupationally and environmentally related parenchymal and pleural abnormalities may be recorded. Although some of the descriptive terms used are associated with pneumoconiosis (e.g., rounded opacities in silicosis, or, in asbestosis, interlobular septal and intralobular non-septal lines, as well as honeycombing) many overlapping patterns that need to be considered for differential diagnosis are also included in the scheme.
Zanatta, Francielle; Gandolfi, Renan Becker; Lemos, Marivane; Ticona, Juan Carlos; Gimenez, Alberto; Clasen, Bruna Kurz; Cechinel Filho, Valdir; de Andrade, Sérgio Faloni
2009-07-15
As part of our continuing search for bioactive natural products from plants, the present study was carried out in order to evaluate the gastroprotective properties of alkaloid extract and 2-phenylquinoline obtained from the bark of Galipea longiflora (Rutaceae). Anti-ulcer assays were performed using the following protocols in mice: nonsteroidal anti-inflammatory drug (NSAID)/bethanecol-induced ulcer, ethanol/HCl-induced ulcer, and stress-induced ulcer. The effects of the extract on gastric content volume, pH and total acidity were also evaluated, using the pylorus ligated model. Treatment using doses of 50, 125 and 250 mg/kg of G. longiflora alkaloid extract and positive controls (omeprazol or cimetidine) significantly diminished the lesion index, total lesion area, and percentage of lesion, in comparison with the negative control groups in all the models evaluated. Regarding the model of gastric secretion, a reduction in volume of gastric juice and total acidity was observed, as well as an increase in gastric pH. The main alkaloid of the plant, 2-phenylquinoline, was also evaluated in the ethanol-induced ulcer model. The results showed that at a dose of 50 mg/kg, it significantly inhibited ulcerative lesions. However, this effect was less than that of the alkaloid extract. All these results taken together show that G. longiflora displays gastroprotective activity, as evidenced by its significant inhibition of the formation of ulcers induced by different models. There are indications that mechanisms involved in anti-ulcer activity are related to a decrease in gastric secretion and an increase in gastric mucus content. Also, there is evidence of involvement of NO in the gastroprotector mechanisms. These effects may be attributed, at least in part, to the presence of some alkaloids, particularly 2-phenylquinoline.
Knowing Our Neighbors: Fundamental Properties of Nearby Stars
NASA Astrophysics Data System (ADS)
Bartlett, Jennifer L.; Ianna, P. A.; Henry, T. J.; Begam, M. C.; Jao, W.; Subasavage, J. P., Jr.; Nearby Stars, Research Consortium on
2007-12-01
Although the stars within 25 pc of the Sun constitute the one stellar sample that we can aspire to know thoroughly, we continue identifying objects closer than 10 pc. We know even less about local substellar populations, especially planets. The Cerro Tololo Inter-American Observatory Parallax Investigation (CTIOPI) is observing 31 late-type, red dwarfs selected for my thesis as part of a larger effort to complete the nearby star census. Preliminary parallaxes substantiate distances less than 25 pc for at least 28 stars. Of these, LP 991-84, LHS 6167, and LP 876-10 may lie within 10 pc. Preliminary proper motions for all but three stars exceed 0.2” yr-1. One recently established neighbor, LP 869-26, also appears to be a new binary. Associated VRI photometry and spectroscopy are in progress as well. Many of these stars are potential targets for astrometric planet searches, such as the Space Interferometry Mission (SIM). In addition to confirming solar neighborhood membership, astrometry can discover brown dwarfs and planets. Time-series analyses of residuals to the UVa Southern Parallax Program (SPP) observations are contributing to frequency and distribution data for nearby substellar objects. In particular, LHS 288 displays an intriguing signal, which might be caused by a very low-mass companion. Twelve other SPP stars demonstrate no significant perturbations. Finally, re-analyzing the Leander McCormick Observatory photographic plates of Barnard's Star failed to detect any planets orbiting it. This study of more than 900 exposures was sensitive to bodies of 2.2 Jupiter masses or more. NSF grants AST 98-20711 and 05-07711, GSU, NASA-SIM, Litton Marine Systems, UVa, Hampden-Sydney College, US Naval Observatory, and the Levinson Fund of the Peninsula Community Foundation supported this research. The ANU Research School of Astronomy & Astrophysics allocated observing time generously. CTIOPI was an NOAO Survey Program and continues as part of the SMARTS Consortium.
Pospos, Sarah; Young, Ilanit Tal; Downs, Nancy; Iglewicz, Alana; Depp, Colin; Chen, James Y; Newton, Isabel; Lee, Kelly; Light, Gregory A; Zisook, Sidney
2018-02-01
Being a healthcare professional can be a uniquely rewarding calling. However, the demands of training and practice can lead to chronic distress and serious psychological, interpersonal, and personal health burdens. Although higher burnout, depression, and suicide rates have been reported in healthcare professionals, only a minority receive treatment. Concerns regarding confidentiality, stigma, potential career implications, and cost and time constraints are cited as key barriers. Web-based and mobile applications have been shown to mitigate stress, burnout, depression, and suicidal ideation among several populations and may circumvent these barriers. Here, we reviewed published data on such resources and selected a small sample that readily can be used by healthcare providers. We searched PubMed for articles evaluating stress, burnout, depression, and suicide prevention or intervention for healthcare students or providers and identified five categories of programs with significant effectiveness: Cognitive Behavioral Therapy (online), meditation, mindfulness, breathing, and relaxation techniques. Using these categories, we searched for Web-based (through Google and beacon.anu.edu.au -a wellness resource website) and mobile applications (Apple and mobile. va.gov/appstore ) for stress, burnout, depression, and suicide prevention and identified 36 resources to further evaluate based on relevance, applicability to healthcare providers (confidentiality, convenience, and cost), and the strength of findings supporting their effectiveness. We selected seven resources under five general categories designed to foster wellness and reduce burnout, depression, and suicide risk among healthcare workers: breathing (Breath2Relax), meditation (Headspace, guided meditation audios), Web-based Cognitive Behavioral Therapy (MoodGYM, Stress Gym), and suicide prevention apps (Stay Alive, Virtual Hope Box). This list serves as a starting point to enhance coping with stressors as a healthcare student or professional in order to help mitigate burnout, depression, and suicidality. The next steps include adapting digital health strategies to specifically fit the needs of healthcare providers, with the ultimate goal of facilitating in-person care when warranted.
The role of IUCN protected area categories in the conservation of geoheritage
NASA Astrophysics Data System (ADS)
Woo, Kyung Sik; Gordon, John E.; Crofts, Roger; Diaz-Martinez, Enrique; McKeever, Patrick J.; Hill, Wesley
2015-04-01
Geoheritage comprises those elements of the Earth's geodiversity that are considered to have significant scientific, educational, cultural/aesthetic, ecological or ecosystem service value. IUCN Resolutions 4.040 (2008) and 5.048 (2012) both clearly recognise that geodiversity is part of nature and geoheritage is part of natural heritage. Formal recognition of the geodiversity component of protected areas was made in 2008 in the revised IUCN Guidelines for Applying Protected Area Management Categories (Dudley, 2008). All 6 of the IUCN Protected Area Management Categories (strict nature reserve/wilderness area, national park, national monument or feature, habitat/species management area, protected landscape/seascape, and protected area with sustainable use of natural resources) are applicable to the protection of geoheritage and provide opportunities to integrate conservation of geosites and the wider landscape values of geodiversity much more closely in protected area networks (Crofts & Gordon, 2015). Although geoparks are not a protected area category as such, and may only include some parts of protected areas as geosites, the UNESCO-supported Global Geoparks Network also provides an international framework to conserve and enhance geoheritage, as does the UNESCO World Heritage List. The Geoheritage Specialist Group of the IUCN World Commission on Protected Areas provides specialist advice and guidance on all aspects of geodiversity and geoheritage in relation to the establishment and management of protected areas, the integration of geodiversity into IUCN's programmes, and the promotion of better understanding of the links between geodiversity and biodiversity. http://www.iucn.org/about/work/programmes/gpap_home/gpap_biodiversity/gpap_wcpabiodiv/gpap_geoheritage/). Crofts, R., Gordon, J. E. (2015) Geoconservation in protected areas. In: G.L. Worboys, M. Lockwood, A. Kothari, S. Feary, I. Pulsford (eds), Protected Area Governance and Management. ANU Press, Canberra, 531-567. Dudley, N. (ed.) (2008) Guidelines for Applying Protected Area Management Categories. IUCN, Gland, Switzerland.
NASA Astrophysics Data System (ADS)
Wyborn, L. A.; Evans, B. J. K.
2015-12-01
The National Computational Infrastructure (NCI) at the Australian National University (ANU) has evolved to become Australia's peak computing centre for national computational and Data-intensive Earth system science. More recently NCI collocated 10 Petabytes of 34 major national and international environmental, climate, earth system, geophysics and astronomy data collections to create the National Environmental Research Interoperability Data Platform (NERDIP). Spatial scales of the collections range from global to local ultra-high resolution, whilst sizes range from 3PB down to a few GB. The data is highly connected to both NCI HPC and cloud resources via low latency internal networks with massive bandwidth. Now that the collections are collocated on a single data platform, the 'Hype' and expectations around potential use cases for the NERDIP are high. Not unexpected issues are emerging such as access, licensing issues, ownership, and incompatible data standards. Many communities are standardised within their domain, but achieving true interdisciplinary science will require all communities to move towards open interoperable data formats such as NetCDF4/HDF5. This transition will impact on software using proprietary or non-open standards. But before we reach the 'Plateau of Productivity', there needs to be greater 'Enlightenment' of users to encourage them to realise that this unprecedented Earth system science platform provides a rich mine of opportunities for discovery and innovation for a diverse range of both domain-specific and interdisciplinary investigations including climate and weather research, impact analysis, environment, remote sensing and geophysics and develop new and innovative interdisciplinary use cases that will guide those architecting the system and help minimise the amplitude of the 'Trough of Disillusionment' and ensure greater productivity and uptake of the collections that make NERDIP unique in the next generation of Data-intensive Science.
NASA Astrophysics Data System (ADS)
Lane, R. J. L.
2015-12-01
At Geoscience Australia, we are upgrading our gravity and magnetic modeling tools to provide new insights into the composition, properties, and structure of the subsurface. The scale of the investigations varies from the size of tectonic plates to the size of a mineral prospect. To accurately model potential field data at all of these scales, we require modeling software that can operate in both spherical and Cartesian coordinate frameworks. The models are in the form of a mesh, with spherical prismatic (tesseroid) elements for spherical coordinate models of large volumes, and rectangular prisms for smaller volumes evaluated in a Cartesian coordinate framework. The software can compute the forward response of supplied rock property models and can perform inversions using constraints that vary from weak generic smoothness through to very specific reference models compiled from various types of "hard facts" (i.e., surface mapping, drilling information, crustal seismic interpretations). To operate efficiently, the software is being specifically developed to make use of the resources of the National Computational Infrastructure (NCI) at the Australian National University (ANU). The development of these tools is been carried out in collaboration with researchers from the Colorado School of Mines (CSM) and the China University of Geosciences (CUG) and is at the stage of advanced testing. The creation of individual 3D geological models will provide immediate insights. Users will also be able to combine models, either by stitching them together or by nesting smaller and more detailed models within a larger model. Comparison of the potential field response of a composite model with the observed fields will give users a sense of how comprehensively these models account for the observations. Users will also be able to model the residual fields (i.e., the observed minus calculated response) to discover features that are not represented in the input composite model.
Variable Mixed Orbital Character in the Photoelectron Angular Distribution of NO_{2}
NASA Astrophysics Data System (ADS)
Laws, Benjamin A.; Cavanagh, Steven J.; Lewis, Brenton R.; Gibson, Stephen T.
2017-06-01
NO_{2} a key component of photochemical smog and an important species in the Earth's atmosphere, is an example of a molecule which exhibits significant mixed orbital character in the HOMO. In photoelectron experiments the geometric properties of the parent anion orbital are reflected in the photoelectron angular distribution (PAD), an area of research that has benefited largely from the ability of velocity-map imaging (VMI) to simultaneously record both the energetic and angular information, with 100% collection efficiency. Photoelectron spectra of NO_{2}^{-}, taken over a range of wavelengths (355nm-520nm) with the ANU's VMI spectrometer, reveal an anomalous jump in the anisotropy parameter near threshold. Consequently, the orbital behavior of NO_{2}^{-} appears to be quite different near threshold compared to detachment at higher photon energies. This surprising effect is due to the Wigner Threshold law, which causes p orbital character to dominate the photodetachment cross-section near threshold, before the mixed s/d orbital character becomes significant at higher electron kinetic energies. By extending recent work on binary character models to form a more general expression, the variable mixed orbital character of NO_{2}^{-} is able to be described. This study provides the first multi-wavelength NO_{2} anisotropy data, which is shown to be in decent agreement with much earlier zero-core model predictions of the anisotropy parameter. K. J. Reed, A. H. Zimmerman, H. C. Andersen, and J. I. Brauman, J. Chem. Phys. 64, 1368, (1976). doi:10.1063/1.432404 D. Khuseynov, C. C. Blackstone, L. M. Culberson, and A. Sanov, J. Chem. Phys. 141, 124312, (2014). doi:10.1063/1.4896241 W. B. Clodius, R. M. Stehman, and S. B. Woo, Phys. Rev. A. 28, 760, (1983). doi:10.1103/PhysRevA.28.760 Research supported by the Australian Research Council Discovery Project Grant DP160102585
The Proteome of Seed Development in the Model Legume Lotus japonicus1[C][W
Dam, Svend; Laursen, Brian S.; Ørnfelt, Jane H.; Jochimsen, Bjarne; Stærfeldt, Hans Henrik; Friis, Carsten; Nielsen, Kasper; Goffard, Nicolas; Besenbacher, Søren; Krusell, Lene; Sato, Shusei; Tabata, Satoshi; Thøgersen, Ida B.; Enghild, Jan J.; Stougaard, Jens
2009-01-01
We have characterized the development of seeds in the model legume Lotus japonicus. Like soybean (Glycine max) and pea (Pisum sativum), Lotus develops straight seed pods and each pod contains approximately 20 seeds that reach maturity within 40 days. Histological sections show the characteristic three developmental phases of legume seeds and the presence of embryo, endosperm, and seed coat in desiccated seeds. Furthermore, protein, oil, starch, phytic acid, and ash contents were determined, and this indicates that the composition of mature Lotus seed is more similar to soybean than to pea. In a first attempt to determine the seed proteome, both a two-dimensional polyacrylamide gel electrophoresis approach and a gel-based liquid chromatography-mass spectrometry approach were used. Globulins were analyzed by two-dimensional polyacrylamide gel electrophoresis, and five legumins, LLP1 to LLP5, and two convicilins, LCP1 and LCP2, were identified by matrix-assisted laser desorption ionization quadrupole/time-of-flight mass spectrometry. For two distinct developmental phases, seed filling and desiccation, a gel-based liquid chromatography-mass spectrometry approach was used, and 665 and 181 unique proteins corresponding to gene accession numbers were identified for the two phases, respectively. All of the proteome data, including the experimental data and mass spectrometry spectra peaks, were collected in a database that is available to the scientific community via a Web interface (http://www.cbs.dtu.dk/cgi-bin/lotus/db.cgi). This database establishes the basis for relating physiology, biochemistry, and regulation of seed development in Lotus. Together with a new Web interface (http://bioinfoserver.rsbs.anu.edu.au/utils/PathExpress4legumes/) collecting all protein identifications for Lotus, Medicago, and soybean seed proteomes, this database is a valuable resource for comparative seed proteomics and pathway analysis within and beyond the legume family. PMID:19129418
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swanson, James
The Dopamine (DA) Hypothesis of ADHD (Wender, 1971; Levy, 1990) suggests that abnormalities in the synaptic mechanisms of DA transmission may be disrupted, and specific abnormalities in DA receptors and DA transporters (DAT) have been proposed (see Swanson et al, 1998). Early studies with small samples (e.g., n = 6, Dougherty et al, 1999) used single photon emission tomography (SPECT) and the radioligand (123I Altropane) to test a theory that ADHD may be caused by an over expression of DAT and reported 'a 70% increase in age-corrected dopamine transporter density in patients with attention deficit hyperactivity disorder compared with healthymore » controls' and suggested that treatment with stimulant medication decreased DAT density in ADHD patients and corrected an underlying abnormality (Krause et al, 2000). The potential importance of these findings was noted by Swanson (1999): 'If true, this is a major finding and points the way for new investigations of the primary pharmacological treatment for ADHD (with the stimulant drugs - e.g., methylphenidate), for which the dopamine transporter is the primary site of action. The potential importance of this finding demands special scrutiny'. This has been provided over the past decade using Positron Emission Tomography (PET). Brain imaging studies were conducted at Brookhaven National Laboratory (BNL) in a relatively large sample of stimulant-naive adults assessed for DAT (11C cocaine) density and DA receptors (11C raclopride) availability. These studies (Volkow et al, 2007; Volkow et al, 2009) do not confirm the hypothesis of increased DAT density and suggest the opposite (i.e., decreased rather than increased DAT density), and follow-up after treatment (Wang et al, 2010) does not confirm the hypothesis that therapeutic doses of methylphenidate decrease DAT density and suggests the opposite (i.e., increased rather than decreased DAT density). The brain regions implicated by these PET imaging studies also suggest that a motivation deficit may contribute as much as an attention deficit to the manifestation of behaviors that underlie the symptoms of ADHD.« less
Gomes de Matos, Elena; Kraus, Ludwig; Hannemann, Tessa-Virginia; Soellner, Renate; Piontek, Daniela
2017-11-01
This study estimates cross-country variation in socioeconomic disparities in adolescent alcohol use and identifies country-level characteristics associated with these disparities. The association between socioeconomic status (family wealth and parental education) and alcohol use (lifetime use and episodic heavy drinking) of 15- to 16-year-olds from 32 European countries was investigated. Country-level characteristics were national income, income inequality and per capita alcohol consumption. Multilevel modelling was applied. Across countries, lifetime use was lower in wealthy than in less wealthy families (odds ratio [OR] (girls) = 0.95, OR (boys) = 0.94). The risk of episodic heavy drinking, in contrast, was higher for children from wealthier families (OR (girls) = 1.04, OR (boys) = 1.08) and lower when parents were highly educated (ORs = 0.95-0.98). Socioeconomic disparities varied substantially between countries. National wealth and income inequality were associated with cross-country variation of disparities in lifetime use in few comparisons, such that among girls, the (negative) effect of family wealth was greatest in countries with unequally distributed income (OR = 0.86). Among boys, the (negative) effect of family wealth was greatest in low-income countries (OR = 1.00), and the (positive) effect of mothers' education was greatest in countries with high income inequality (OR = 1.11). Socioeconomic disparities in adolescent alcohol use vary across European countries. Broad country-level indicators can explain this variation only to a limited extent, but results point towards slightly greater socioeconomic disparities in drinking in countries of low national income and countries with a high income inequality. [Gomes de Matos E, Kraus L, Hannemann T-V, Soellner R, Piontek D. Cross-cultural variation in the association between family's socioeconomic status and adolescent alcohol use. © 2017 Australasian Professional Society on Alcohol and other Drugs.
Study of edge turbulence in dimensionally similar laboratory plasmas
NASA Astrophysics Data System (ADS)
Stroth, Ulrich
2003-10-01
In recent years, the numerical simulation of turbulence has made considerable progress. Predictions are made for large plasma volumes taking into account realistic magnetic geometries. Because of diagnostic limitations, in fusion plasmas the means of experimental testing of the models are rather limited. Toroidal low-temperature plasmas offer the possibility for detailed comparisons between experiment and simulation. Due to the reduced plasma parameters, the relevant quantities can be measured in the entire plasma. At the same time, the relevant non-dimensional parameters can be comparable to those in the edge of fusion plasmas. This presentation reports on results from the torsatron TJ-K [1,2] operated with a low-temperature plasma. The data are compared with simulations using the drift-Alfven-wave code DALF3 [3]. Langmuir probe arrays with 64 tips are used to measure the spatial structure of the turbulence. The same analyses techniques are applied to experimental and numerical data. The measured properties of spectra and probability density functions are reproduced by the code. Although the plasma in experiment and simulation does not exhibit critical pressure gradients, the radial transport fluctuations are strongly intermittent in both cases. Using Hydrogen, Helium and Argon as working gases, the scale parameter ρs could be varied by more than a factor of ten. As predicted by theory, the size of the turbulent eddies increases with ρ_s. The measured cross-phase between density and potential fluctuations are small, indicating the importance of the drift-wave dynamics for the turbulence in toroidal plasmas. The wave number spectra decay with an exponent of -3 as one would expect for the enstrophy cascade in 2D turbulence. [1] N. Krause et al., Rev. Sci. Instr. 73, 3474 (2002) [2] C. Lechte et al., New J. of Physics 4, 34 (2002) [3] B. Scott, Plasma Phys. Contr. Fusion 39, 1635 (1997)
NASA Astrophysics Data System (ADS)
Pasche, E.; Manojlovic, N.; Basener, S.; Behzadnia, N.
2009-04-01
In the paradigm shift in flood management from traditional to more integrated approach the key to initialising this transition stage is capacity building of stakeholders. It supports the effective participation of stakeholders within their role by giving the individuals/professionals and institutions required knowledge and skills. Such a process of empowering targeted stakeholder groups should be based on the interactive learning rather than mere delivering of flood related information. It can be achieved by initiating the learning process and developing life-long learning programs in form of blended learning that combines both, supervised online and face-to-face approaches. The learning concept based on the didactic principle of Kolb/Fry, has been used as a basis for development of the Interactive Learning Program (ILP) presented in this paper. Kolb/Fry define learning as a cyclic process dividing it into four steps: concrete experience, reflection & observation, forming abstract concepts, testing of acquainted knowledge in new situations. As the knowledge to understand the complexity of IFM is extensive and required level usually cannot be achieved within the face-to-face phase, additional autodidactic learning module tailored to the individual skills should be included in the learning program. ILP combines both, the face-to-face sessions following the Kolb?s learning cycle including theoretical and practical aspects and autodidactic phase by means of the e-learning platform based on the web dissemination strategy for IFM- Kalypso Inform (Pasche/Kraus/Manojlovic). According to this strategy, the access to the flood related information is enabled through three different modules Tutorial, Knowledge Base and Virtual Trainer enabling interaction with the system. This ILP is generic and can be tailored to requirements of different stakeholder groups depending on their role and level of integration in IFM. The first results, obtained for both public and private stakeholders, are encouraging indicating that such concepts should become a substantial part of the IFM.
Tellurium Stable Isotopes as a Paleoredox Proxy
NASA Astrophysics Data System (ADS)
Wasserman, N.; Johnson, T. M.
2017-12-01
Despite arguments for variably-oxygenated shallow waters and anoxic deep marine waters, which delayed animal development until the Neoproterozoic Oxidation Event, the magnitude of atmospheric oxygen during the Proterozoic is still uncertain [1]. The evidence for low pO2 (<0.1-1% PAL) is based on geochemical and isotopic proxies, which track the mobilization of Fe and Mn on the continents. For example, large chromium isotope shifts occur at the Neoproterozoic Oxidation Event due to the initiation of Cr redox cycling, but this proxy is insensitive to fluctuations in the lower-pO2 conditions at other times during the Proterozoic. Tellurium, a metalloid with a lower threshold to oxidation, may be sensitive to pO2 shifts in a lower range. In the reduced forms, Te(-II) and Te(0), the element is insoluble and immobile. However, in the more oxidized phases, Te(IV) and Te(VI), Te can form soluble oxyanions (though it tends to adsorb to Fe-oxyhydroxides and clays) [2]. Te stable isotopes have been shown to fractionate during abiotic or biologic reduction of Te(VI) or Te(IV) to elemental Te(0) [3, 4]. Utilizing hydride generation MC-ICP-MS, we are able to obtain high precision (2σ 0.04‰) measurements of δ128Te/125Te for natural samples containing < 10 ng of Te. A suite of Phanerozoic and Proterozoic ironstones show significant variation in δ128Te/125Te (<0.5‰), suggesting that the Te redox cycle was active during the Proterozoic. Future directions will include Te isotope measurements of Precambrian paleosols to determine natural isotope variation before the Great Oxidation Event and experiments to determine fractionation during adsorption to Fe-oxyhydroxides. [1] Planavsky et al. (2014) Science 346 (6209), pp. 635-638 [2] Qin et al. (2017) Environmental Science and Technology 51 (11), pp 6027-6035 [3] Baesman et al. (2007) Applied Environmental Microbiology 73 (7), pp 2135-2143 [4] Smithers and Krause (1968) Canadian Journal of Chemistry 46(4): pp 583-591
Evaluation of the Dopamine Hypothesis of ADHD with PET Brain Imaging
Swanson, James
2018-01-24
The Dopamine (DA) Hypothesis of ADHD (Wender, 1971; Levy, 1990) suggests that abnormalities in the synaptic mechanisms of DA transmission may be disrupted, and specific abnormalities in DA receptors and DA transporters (DAT) have been proposed (see Swanson et al, 1998). Early studies with small samples (e.g., n = 6, Dougherty et al, 1999) used single photon emission tomography (SPECT) and the radioligand (123I Altropane) to test a theory that ADHD may be caused by an over expression of DAT and reported 'a 70% increase in age-corrected dopamine transporter density in patients with attention deficit hyperactivity disorder compared with healthy controls' and suggested that treatment with stimulant medication decreased DAT density in ADHD patients and corrected an underlying abnormality (Krause et al, 2000). The potential importance of these findings was noted by Swanson (1999): 'If true, this is a major finding and points the way for new investigations of the primary pharmacological treatment for ADHD (with the stimulant drugs - e.g., methylphenidate), for which the dopamine transporter is the primary site of action. The potential importance of this finding demands special scrutiny'. This has been provided over the past decade using Positron Emission Tomography (PET). Brain imaging studies were conducted at Brookhaven National Laboratory (BNL) in a relatively large sample of stimulant-naive adults assessed for DAT (11C cocaine) density and DA receptors (11C raclopride) availability. These studies (Volkow et al, 2007; Volkow et al, 2009) do not confirm the hypothesis of increased DAT density and suggest the opposite (i.e., decreased rather than increased DAT density), and follow-up after treatment (Wang et al, 2010) does not confirm the hypothesis that therapeutic doses of methylphenidate decrease DAT density and suggests the opposite (i.e., increased rather than decreased DAT density). The brain regions implicated by these PET imaging studies also suggest that a motivation deficit may contribute as much as an attention deficit to the manifestation of behaviors that underlie the symptoms of ADHD.
X-ray fluorescence cross sections for K and L x rays of the elements
DOE Office of Scientific and Technical Information (OSTI.GOV)
Krause, M.O.; Nestor, C.W. Jr.; Sparks, C.J. Jr.
1978-06-01
X-ray fluorescence cross sections are calculated for the major x rays of the K series 5 less than or equal to Z less than or equal to 101, and the three L series 12 less than or equal to Z less than or equal to 101 in the energy range 1 to 200 keV. This calculation uses Scofield's theoretical partical photoionization cross sections, Krause's evaluation of fluorescence and Coster-Kronig yields, and Scofield's theoretical radiative rates. Values are presented in table and graph format, and an estimate of their accuracy is made. The following x rays are considered: K..cap alpha../sub 1/,more » K..cap alpha../sub 1/,/sub 2/, K..beta../sub 1/, K..beta../sub 1/,/sub 3/, L..cap alpha../sub 1/, L..cap alpha../sub 1/,/sub 2/, L..beta../sub 1/, L..beta../sub 2/,/sub 15/, L..beta../sub 3/, Ll, L..gamma../sub 1/, L..gamma../sub 4/, and L/sub 1/ ..-->.. L/sub 2/,/sub 3/. For use in x-ray fluorescence analysis, K..cap alpha.. and L..cap alpha.. fluorescence cross sections are presented at specific energies: TiK identical with 4.55 keV, CrK identical with 5.46 keV, CoK identical with 7.00 keV, CuK identical with 8.13 keV, MoK..cap alpha.. identical with 17.44 keV, AgK identical with 22.5 keV, DyK identical with 47.0 keV, and /sup 241/Am identical with 59.54 keV. Supplementary material includes fluorescence and Coster--Kronig yields, fractional radiative rates, fractional fluorescence yields, total L-shell fluorescence cross sections, fluorescence and Coster-Kronig yields in condensed matter, effective fluorescence yields, average L-shell fluorescence yield, L-subshell photoionization cross section ratios, and conversion factors from barns per atom to square centimeters per gram.« less
Estimating high-risk cannabis and opiate use in Ankara, Istanbul and Izmir.
Kraus, Ludwig; Hay, Gordon; Richardson, Clive; Yargic, Ilhan; Ilhan, Mustafa Necmi; Ay, Pinar; Karasahin, Füsun; Pinarci, Mustafa; Tuncoglu, Tolga; Piontek, Daniela; Schulte, Bernd
2017-09-01
Information on high-risk drug use in Turkey, particularly at the regional level, is lacking. The present analysis aims at estimating high-risk cannabis use (HRCU) and high-risk opiate use (HROU) in the cities of Ankara, Istanbul and Izmir. Capture-recapture and multiplier methods were applied based on treatment and police data stratified by age and gender in the years 2009 and 2010. Case definitions refer to ICD-10 cannabis (F.12) and opiate (F.11) disorder diagnoses from outpatient and inpatient treatment records and illegal possession of these drugs as recorded by the police. High-risk cannabis use was estimated at 28 500 (8.5 per 1000; 95% confidence interval 7.3-10.3) and 33 400 (11.9 per 1000; 95% confidence interval 10.7-13.5) in Ankara and Izmir, respectively. Using multipliers based on capture-recapture estimates for Izmir, HRCU in Istanbul was estimated up to 166 000 (18.0 per 1000; range: 2.8-18.0). Capture-recapture estimates of HROU resulted in 4800 (1.4 per 1000; 95% confidence interval 0.9-1.9) in Ankara and multipliers based on these gave estimates up to 20 000 (2.2 per 1000; range: 0.9-2.2) in Istanbul. HROU in Izmir was not estimated due to the low absolute numbers of opiate users. While HRCU prevalence in both Ankara and Izmir was considerably lower in comparison to an estimate for Berlin, the rate for Istanbul was only slightly lower. Compared with the majority of European cities, HROU in these three Turkish cities may be considered rather low. [Kraus L, Hay G, Richardson C, Yargic I, Ilhan N M, Ay P, Karasahin F, Pinarci M, Tuncoglu T, Piontek D, Schulte B Estimating high-risk cannabis and opiate use in Ankara, Istanbul and Izmir Drug Alcohol Rev 2016;00:000-000]. © 2016 Australasian Professional Society on Alcohol and other Drugs.
Multi-resolution integrated modeling for basin-scale water resources management and policy analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gupta, Hoshin V.; Brookshire, David S.; Springer, E. P.
Approximately one-third of the land surface of the Earth is considered to be arid or semi-arid with an annual average of less than 12-14 inches of rainfall. The availability of water in such regions is of course, particularly sensitive to climate variability while the demand for water is experiencing explosive population growth. The competition for available water is exerting considerable pressure on the water resources management. Policy and decision makers in the southwestern U.S. increasingly have to cope with over-stressed rivers and aquifers as population and water demands grow. Other factors such as endangered species and Native American water rightsmore » further complicate the management problems. Further, as groundwater tables are drawn down due to pumping in excess of natural recharge, considerable (potentially irreversible) environmental impacts begin to be felt as, for example, rivers run dry for significant portions of the year, riparian habitats disappear (with consequent effects on the bio-diversity of the region), aquifers compact resulting in large scale subsidence, and water quality begins to suffer. The current drought (1999-2002) in the southwestern U.S. is raising new concerns about how to sustain the combination of agricultural, urban and in-stream uses of water that underlie the socio-economic and ecological structure in the region. The water stressed nature of arid and semi-arid environments means that competing water uses of various kinds vie for access to a highly limited resource. If basin-scale water sustainability is to be achieved, managers must somehow achieve a balance between supply and demand throughout the basin, not just for the surface water or stream. The need to move water around a basin such as the Rio Grande or Colorado River to achieve this balance has created the stimulus for water transfers and water markets, and for accurate hydrologic information to sustain such institutions [Matthews et al. 2002; Brookshire et al 2003; Krause, Chermak Brookshire, 2003].« less
NASA Astrophysics Data System (ADS)
Barthel, Roland; Rojanschi, Vlad; Wolf, Jens; Braun, Juergen
The research project GLOWA-Danube, financed by the German Federal Government, is investigating long-term changes in the water cycle of the upper Danube river basin (77,000 km 2) in light of global climatic change. Its aim is to build a fully integrated decision-support tool “DANUBIA” that combines the competence of 11 different research institutes in domains covering all major aspects governing the water cycle-from the formation of clouds, to groundwater flow patterns, to the behaviour of the water consumer. Both the influence of natural changes in the ecosystem, such as climate change, and changes in human behaviour, such as changes in land use or water consumption, are considered. DANUBIA is comprised of 15 individual disciplinary models that are connected via customized interfaces that facilitate network-based parallel calculations. The strictly object-oriented DANUBIA architecture was developed using the graphical notation tool UML (Unified Modeling Language) and has been implemented in Java code. All models use the same spatial discretisation for the exchange of data (1 × 1 km grid cells) but are using different time steps. The representation of a vast number of relevant physical and social processes that occur at different spatial and temporal scales is a very demanding task. Newly developed up- and downscaling procedures [Rojanschi, V., 2001. Effects of upscaling for a finite-difference flow model. Master’s Thesis, Institut für Wasserbau, Universität Stuttgart, Stuttgart, Germany] and a sophisticated time controller developed by the computer sciences group [Hennicker, R., Barth, M., Kraus, A., Ludwig, M., 2002. DANUBIA: A Web-based modelling and decision support system for integrative global change research in the upper Danube basin. In: GSF (Ed.), GLOWA, German Program on Global Change in the Hydrological Cycle Status Report 2002. GSF, Munich, pp. 35-38; Kraus, A., Ludwig, M., 2003. GLOWA-Danube Papers Technical Release No. 002 (Danubia Framework), Software-Release No.: 0.9.2, Documentation Version: 0.10, Release Date: 27 March 2003] are required to solve the emerging problems. After a first successful public demonstration of the DANUBIA package (nine models) in May 2002 [Mauser, W., Stolz, R., Colgan, A., 2002. GLOWA-Danube: integrative techniques, scenarios and strategies regarding global change of the water cycle. In: GSF (Ed.), GLOWA, German Program on Global Change in the Hydrological Cycle (Phase I, 2000-2003) Status Report 2002. GSF, Munich, pp. 31-34], the research consortium is now preparing a first validation run of DANUBIA for the period 1995-1999 with all 15 models. After successful completion of the validation, a scenario run based on IPCC climate scenarios [IPCC, 2001. Climate Change 2001: Synthesis Report. In: Watson, R.T., Core Writing Team (Eds.), A Contribution of Working Groups I, II, and III to the Third Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK and New York, NY, USA, 398pp] for a five year period between 2025 and 2040 will follow at the end of 2003. The research group “Groundwater and Water Resources Management” at the Institute of Hydraulic Engineering, Universität Stuttgart, is contributing both a three-dimensional groundwater flow model of the catchment and an agent-based model for simulating water supply and distribution. This paper gives a general overview of the GLOWA-Danube project and describes the groundwater modeling segment. Nickel et al. deal with the water supply model in a second contribution to this special issue. A three-dimensional numerical groundwater flow model consisting of four main layers has been developed and is in a continual state of refinement (MODFLOW, [McDonald, M.G., Harbaugh, A.W., 1988. A modular three-dimensional finite-difference ground-water flow model: US Geological Survey Techniques of Water-Resources Investigations, Washington, USA (book 6, Chapter A1)]). One main research focus has been on the investigation of upscaling techniques to meet the requirement of a fixed 1 × 1 km cell size. This cell size is compulsory for all models in DANUBIA in order to facilitate a one to one parameter exchange. In a second stage, a transport model (nitrogen) will be added (MT3D: [Zheng, C., Hathaway, D.-L., 1991. MT3D: a new modular three-dimensional transport model and its application in predicting the persistence and transport of dissolved compounds from a gasoline spill, with implications for remediation. Association of Ground Water Scientists and Engineers Annual Meeting on Innovative Ground Water Technologies for the ’90s, National Ground Water Association, Westerville, Ohio, USA. Ground Water 29 (5)].
NASA Astrophysics Data System (ADS)
Korzeniowska, Karolina; Mandlburger, Gottfried; Klimczyk, Agata
2013-04-01
The paper presents an evaluation of different terrain point extraction algorithms for Airborne Laser Scanning (ALS) point clouds. The research area covers eight test sites in the Małopolska Province (Poland) with varying point density between 3-15points/m² and surface as well as land cover characteristics. In this paper the existing implementations of algorithms were considered. Approaches based on mathematical morphology, progressive densification, robust surface interpolation and segmentation were compared. From the group of morphological filters, the Progressive Morphological Filter (PMF) proposed by Zhang K. et al. (2003) in LIS software was evaluated. From the progressive densification filter methods developed by Axelsson P. (2000) the Martin Isenburg's implementation in LAStools software (LAStools, 2012) was chosen. The third group of methods are surface-based filters. In this study, we used the hierarchic robust interpolation approach by Kraus K., Pfeifer N. (1998) as implemented in SCOP++ (Trimble, 2012). The fourth group of methods works on segmentation. From this filtering concept the segmentation algorithm available in LIS was tested (Wichmann V., 2012). The main aim in executing the automatic classification for ground extraction was operating in default mode or with default parameters which were selected by the developers of the algorithms. It was assumed that the default settings were equivalent to the parameters on which the best results can be achieved. In case it was not possible to apply an algorithm in default mode, a combination of the available and most crucial parameters for ground extraction were selected. As a result of these analyses, several output LAS files with different ground classification were achieved. The results were described on the basis of qualitative and quantitative analyses, both being in a formal description. The classification differences were verified on point cloud data. Qualitative verification of ground extraction was made on the basis of a visual inspection of the results (Sithole G., Vosselman G., 2004; Meng X. et al., 2010). The results of these analyses were described as a graph using weighted assumption. The quantitative analyses were evaluated on a basis of Type I, Type II and Total errors (Sithole G., Vosselman G., 2003). The achieved results show that the analysed algorithms yield different classification accuracies depending on the landscape and land cover. The simplest terrain for ground extraction was flat rural area with sparse vegetation. The most difficult were mountainous areas with very dense vegetation where only a few ground points were available. Generally the LAStools algorithm gives good results in every type of terrain, but the ground surface is too smooth. The LIS Progressive Morphological Filter algorithm gives good results in forested flat and low slope areas. The surface-based algorithm from SCOP++ gives good results in mountainous areas - both forested and built-up because it better preserves steep slopes, sharp ridges and breaklines, but sometimes it fails to remove off-terrain objects from the ground class. The segmentation-based algorithm in LIS gives quite good results in built-up flat areas, but in forested areas it does not work well. Bibliography: Axelsson, P., 2000. DEM generation from laser scanner data using adaptive TIN models. International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XXXIII (Pt. B4/1), 110- 117 Kraus, K., Pfeifer, N., 1998. Determination of terrain models in wooded areas with airborne laser scanner data. ISPRS Journal of Photogrammetry & Remote Sensing 53 (4), 193-203 LAStools website http://www.cs.unc.edu/~isenburg/lastools/ (verified in September 2012) Meng, X., Currit, N., Zhao, K., 2010. Ground Filtering Algorithms for Airborne LiDAR Data: A Review of Critical Issues. Remote Sensing 2, 833-860 Sithole, G., Vosselman, G., 2003. Report: ISPRS Comparison of Filters. Commission III, Working Group 3. Department of Geodesy, Faculty of Civil Engineering and Geosciences, Delft University of technology, The Netherlands Sithole, G., Vosselman, G., 2004. Experimental comparison of filter algorithms for bare-Earth extraction form airborne laser scanning point clouds. ISPRS Journal of Photogrammetry & Remote Sensing 59, 85-101 Trimble, 2012 http://www.trimble.com/geospatial/aerial-software.aspx (verified in November 2012) Wichmann, V., 2012. LIS Command Reference, LASERDATA GmbH, 1-231 Zhang, K., Chen, S.-C., Whitman, D., Shyu, M.-L., Yan, J., Zhang, C., 2003. A progressive morphological filter for removing non-ground measurements from airborne LIDAR data. IEEE Transactions on Geoscience and Remote Sensing, 41(4), 872-882
PyEvolve: a toolkit for statistical modelling of molecular evolution.
Butterfield, Andrew; Vedagiri, Vivek; Lang, Edward; Lawrence, Cath; Wakefield, Matthew J; Isaev, Alexander; Huttley, Gavin A
2004-01-05
Examining the distribution of variation has proven an extremely profitable technique in the effort to identify sequences of biological significance. Most approaches in the field, however, evaluate only the conserved portions of sequences - ignoring the biological significance of sequence differences. A suite of sophisticated likelihood based statistical models from the field of molecular evolution provides the basis for extracting the information from the full distribution of sequence variation. The number of different problems to which phylogeny-based maximum likelihood calculations can be applied is extensive. Available software packages that can perform likelihood calculations suffer from a lack of flexibility and scalability, or employ error-prone approaches to model parameterisation. Here we describe the implementation of PyEvolve, a toolkit for the application of existing, and development of new, statistical methods for molecular evolution. We present the object architecture and design schema of PyEvolve, which includes an adaptable multi-level parallelisation schema. The approach for defining new methods is illustrated by implementing a novel dinucleotide model of substitution that includes a parameter for mutation of methylated CpG's, which required 8 lines of standard Python code to define. Benchmarking was performed using either a dinucleotide or codon substitution model applied to an alignment of BRCA1 sequences from 20 mammals, or a 10 species subset. Up to five-fold parallel performance gains over serial were recorded. Compared to leading alternative software, PyEvolve exhibited significantly better real world performance for parameter rich models with a large data set, reducing the time required for optimisation from approximately 10 days to approximately 6 hours. PyEvolve provides flexible functionality that can be used either for statistical modelling of molecular evolution, or the development of new methods in the field. The toolkit can be used interactively or by writing and executing scripts. The toolkit uses efficient processes for specifying the parameterisation of statistical models, and implements numerous optimisations that make highly parameter rich likelihood functions solvable within hours on multi-cpu hardware. PyEvolve can be readily adapted in response to changing computational demands and hardware configurations to maximise performance. PyEvolve is released under the GPL and can be downloaded from http://cbis.anu.edu.au/software.
Christensen, Helen; Griffiths, Kathleen M; Korten, Ailsa
2002-01-01
Cognitive behavior therapy is well recognized as an effective treatment and prevention for depression when delivered face-to-face, via self-help books (bibliotherapy), and through computer administration. The public health impact of cognitive behavior therapy has been limited by cost and the lack of trained practitioners. We have developed a free Internet-based cognitive behavior therapy intervention (MoodGYM, http://moodgym.anu.edu.au) designed to treat and prevent depression in young people, available to all Internet users, and targeted to those who may have no formal contact with professional help services. To document site usage, visitor characteristics, and changes in depression and anxiety symptoms among users of MoodGYM, a Web site delivering a cognitive-behavioral-based preventive intervention to the general public. All visitors to the MoodGYM site over about 6 months were investigated, including 2909 registrants of whom 1503 had completed at least one online assessment. Outcomes for 71 university students enrolled in an Abnormal Psychology course who visited the site for educational training were included and examined separately. The main outcome measures were (1) site-usage measures including number of sessions, hits and average time on the server, and number of page views; (2) visitor characteristics including age, gender, and initial Goldberg self-report anxiety and depression scores; and (3) symptom change measures based on Goldberg anxiety and depression scores recorded on up to 5 separate occasions. Over the first almost-6-month period of operation, the server recorded 817284 hits and 17646 separate sessions. Approximately 20% of sessions lasted more than 16 minutes. Registrants who completed at least one assessment reported initial symptoms of depression and anxiety that exceeded those found in population-based surveys and those characterizing a sample of University students. For the Web-based population, both anxiety and depression scores decreased significantly as individuals progressed through the modules. CONCLUSIONS Web sites are a practical and promising means of delivering cognitive behavioral interventions for preventing depression and anxiety to the general public. However, randomized controlled trials are required to establish the effectiveness of these interventions.
Radiation Halos, a Rare Microstructure in Diamonds From the Central African Republic
NASA Astrophysics Data System (ADS)
Vicenzi, E. P.; Heaney, P. J.; Snyder, K.; Armstrong, L.
2002-05-01
The geochemical characterization of bulk diamonds and associated inclusions as a tool for determining provenance carries significant inherent limitations. Isotopic and trace element signatures are imparted within the mantle during diamond growth; hence, discriminating crystals from a particular region on the Earth's surface on this basis is difficult at best, and impossible (using current technologies) in many cases. In contrast, rare diamond characteristics may provide a partial solution for recognizing stones from a limited number of localities. Here we discuss an analysis of radiation halos in alluvially deposited polycrystalline diamonds (carbonados) from the Central African Republic (CAR). Large amounts of implanted Xe and Kr, as well as isotopic ratios of those elements consistent with fission, in carbonado strongly suggest that diamond crystallization took place in the presence of significant quantities of uranium [1]. Such ionizing radiation ultimately results in the loss of periodicity of the diamond structure. Crystallographically damaged areas produce fewer photons in cathodoluminescence microscopy, and therefore, the metamict regions resulting from point source radiation in diamond can be visualized on the scale of ~1-25 micrometers [2]. Because intermediate daughter products in the decay chain release alpha particles at differing energies, a ``bull's eye'' pattern is produced in 2-D by the point source radiation. Radiation haloes have been previously observed in carbonados and are thought to result from U deposition associated with fluids following diamond formation [3,4]. We have made a series of measurements of the apparent diameter of the largest circle within a damage halo. By comparing the statistical distribution of this dimension to the distribution expected for a series of circles resulting from random sectioning of mono-sized spheres, one can estimate whether the radiation resulted from one or more fluid pulses widely separated in time. Preliminary data are consistent with a single pulse of uranium deposition in CAR carbonado. [1] Ozima et al. 1991, Nature 351 : 472. [2] Mendelssohn et al. 1979, Diamond Research:35. [3] Milledge et al. 1998, 7th Intl. Kimberlite Conf: 589. [4] Magee 2001, Ph.D. ANU 247p.
The IRHUM database - bioavailable strontium isotope ratios of France for geochemical fingerprinting
NASA Astrophysics Data System (ADS)
Willmes, Malte; Moffat, Ian; Grün, Rainer; Armstrong, Richard; Kinsley, Les; McMorrow, Linda
2013-04-01
Strontium isotope ratios (87Sr/86Sr) are used as a geochemical tracer in a wide range of fields including archaeology, ecology, soil, food and forensic sciences. These applications are based on the principle that strontium isotopic ratios of materials reflect the geological sources of the strontium, which were available during its formation. Geologic regions with distinct strontium isotope ranges, which depend on their age and composition, can be differentiated. A major constraint for current studies is the lack of robust reference maps to evaluate the strontium isotope ratios measured in the samples. The aim of the IRHUM (isotopic reconstruction of human migration) database is to provide a reference map of bioavailable strontium isotope ratios for continental France. The current dataset contains 400 sample locations covering the major geologic units of the Paris and Aquitaine Basin, the Massif Central, and the Pyrenees. At each site soil and plant samples have been collected to cover the whole range of strontium ratios at a specific location. The database is available online at www.rses.anu.edu.au/research-areas/archaeogeochemistry and contains the bioavailable strontium isotope data as well as major and trace element concentrations for soil and plant samples. Strontium isotopes were analysed using a Neptune multi-collector inductively-coupled plasma mass spectrometer (MC-ICP-MS) and elemental concentrations with a Varian Vista Pro Axial ICP-AES (inductively-coupled plasma atomic emission spectrometer). In addition, IRHUM provides spatial context for each sample, including background geology, field observations and soil descriptions. This metadata allows users to evaluate the suitability of a specific data point for their study. The IRHUM database fills an important gap between high resolution studies from specific sites (e.g. archaeological sites), to the very broad geochemical mapping of Europe. Thus it provides an excellent tool to evaluate the regional context of a sample and complement more closed spaced studies. New results will be added to the database continuously with the aim of covering all major geologic units of France within the next year.
NASA Astrophysics Data System (ADS)
Tesauro, M.; Kaban, M. K.; Aitken, A.
2017-12-01
The Australian plate has a long and complex tectonic history and its crust and upper mantle have been deeply investigated in the last two decades using a variety of geophysical methods. To discern temperature and compositional variations of the Australian upper mantle, we apply an iterative technique, which jointly interprets seismic tomography and gravity data. This technique consists in removing the effect of the crust from the observed gravity field and topography. In the second step, the residual mantle gravity field and residual topography are inverted to obtain a 3-D density model of the upper mantle. The inversion technique accounts for the notion that these fields are controlled by the same factors but in a different way (e.g., depending on depth and horizontal dimension of the heterogeneity.) This enables us to locate the position of principal density anomalies in the upper mantle. Afterwards, the thermal contribution to the density structure is estimated by inverting the seismic tomography model AusREM (http://rses.anu.edu.au/seismology/AuSREM/index.php). In this way, we improve the initial thermal and compositional models iteratively. The final thermal model compared to the initial one shows temperatures higher by 100-150 °C in the Archean and Proterozoic upper mantle. Furthermore, we observe larger iron depletion in the Western Australian craton than in the Proterozoic terranes. At the depths larger than 150 km, the depletion becomes negligible beneath the Proterozoic regions, while persists in the Western Australian craton also below the depth of the lithosphere. We interpret this feature as a result of the leakage of the depleted mantle, possibly caused by the erosion of the thermal boundary layer, which was thicker before than in present-days. Using the final thermo-compositional model, we estimated the strength and effective elastic distribution within the Australian lithosphere. For this purpose, we assumed a stiff rheology, on account of the mafic composition of the Australian crust. The results show large variability of the rigidity of the plate within the cratonic areas, reflecting the long tectonic history of the Australian plate. On the other hand, the younger eastern terranes are uniformly weak, due to the higher temperatures.
Chen, Jingguang; Fan, Xiaoru; Qian, Kaiyun; Zhang, Yong; Song, Miaoquan; Liu, Yu; Xu, Guohua; Fan, Xiaorong
2017-10-01
The nitrate (NO3-) transporter has been selected as an important gene maker in the process of environmental adoption in rice cultivars. In this work, we transferred another native OsNAR2.1 promoter with driving OsNAR2.1 gene into rice plants. The transgenic lines with exogenous pOsNAR2.1:OsNAR2.1 constructs showed enhanced OsNAR2.1 expression level, compared with wild type (WT), and 15 N influx in roots increased 21%-32% in response to 0.2 mm and 2.5 mm 15NO3- and 1.25 mm 15 NH 4 15 NO 3 . Under these three N conditions, the biomass of the pOsNAR2.1:OsNAR2.1 transgenic lines increased 143%, 129% and 51%, and total N content increased 161%, 242% and 69%, respectively, compared to WT. Furthermore in field experiments we found the grain yield, agricultural nitrogen use efficiency (ANUE), and dry matter transfer of pOsNAR2.1:OsNAR2.1 plants increased by about 21%, 22% and 21%, compared to WT. We also compared the phenotypes of pOsNAR2.1:OsNAR2.1 and pOsNAR2.1:OsNRT2.1 transgenic lines in the field, found that postanthesis N uptake differed significantly between them, and in comparison with the WT. Postanthesis N uptake (PANU) increased approximately 39% and 85%, in the pOsNAR2.1:OsNAR2.1 and pOsNAR2.1:OsNRT2.1 transgenic lines, respectively, possibly because OsNRT2.1 expression was less in the pOsNAR2.1:OsNAR2.1 lines than in the pOsNAR2.1:OsNRT2.1 lines during the late growth stage. These results show that rice NO 3 - uptake, yield and NUE were improved by increased OsNAR2.1 expression via its native promoter. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Approaches to local climate action in Colorado
NASA Astrophysics Data System (ADS)
Huang, Y. D.
2011-12-01
Though climate change is a global problem, the impacts are felt on the local scale; it follows that the solutions must come at the local level. Fortunately, many cities and municipalities are implementing climate mitigation (or climate action) policies and programs. However, they face many procedural and institutional barriers to their efforts, such of lack of expertise or data, limited human and financial resources, and lack of community engagement (Krause 2011). To address the first obstacle, thirteen in-depth case studies were done of successful model practices ("best practices") of climate action programs carried out by various cities, counties, and organizations in Colorado, and one outside Colorado, and developed into "how-to guides" for other municipalities to use. Research was conducted by reading documents (e.g. annual reports, community guides, city websites), email correspondence with program managers and city officials, and via phone interviews. The information gathered was then compiled into a series of reports containing a narrative description of the initiative; an overview of the plan elements (target audience and goals); implementation strategies and any indicators of success to date (e.g. GHG emissions reductions, cost savings); and the adoption or approval process, as well as community engagement efforts and marketing or messaging strategies. The types of programs covered were energy action plans, energy efficiency programs, renewable energy programs, and transportation and land use programs. Between the thirteen case studies, there was a range of approaches to implementing local climate action programs, examined along two dimensions: focus on climate change (whether it was direct/explicit or indirect/implicit) and extent of government authority. This benchmarking exercise affirmed the conventional wisdom propounded by Pitt (2010), that peer pressure (that is, the presence of neighboring jurisdictions with climate initiatives), the level of community engagement and enthusiasm, and most importantly staff members dedicated to the area of climate planning have a significant effect on climate mitigation policy adoption. In addition, it supported the claim asserted by Toly (2008) that an emphasis on economic co-benefits perpetuates the principle that economic growth need not be compromised when addressing climate change and weakens our capacity to shift toward a bolder paradigm in what is politically achievable in climate legislation.
New insights on multiplicity and clustering in Taurus.
NASA Astrophysics Data System (ADS)
Joncour, Isabelle; Duchene, Gaspard; Moraux, Estelle; Mundy, Lee
2018-01-01
Multiplicity and clustering of young stars are critical clues to constraint star formation process. The Taurus molecular complex is the archetype of a quiescent star forming region that may retain primeval signature of star formation.Using statistical and clustering tools such as nearest neighbor statistics, correlation functions and the density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm, this work reveals new spatial substructures in Taurus.We have identified unexpected ultra wide pairs (UWPs) candidates of high order multiplicity in Taurus in the 5-60 kAU separation range (Joncour et al 2017), beyond the separation assessed for wide pairs (Kraus & Hillenbrand 2009).Our work reveals 20 local stellar substructures, the Nested Elementary Structures (NESTs). These NESTs contain nearly half the stars of Taurus and 75% of the Class 0/I objects probing that they are the preferred sites of star formation (Joncour et al, sub.). The NESTs size ranges from few kAU up to 80 kAU making a length scale bridge between wide pairs and loose group (few hundreds kAU, Kirk & Myers, 2011). The NESTs mass ranges from 0.5-10 solar mass. The balance between Class I, II and III in NESTs suggests that they may be ordered as an evolutionary temporal scheme, some of them got infertile, while other shelter stars in infancy.The UWPs and the NESTs may be pristine imprints of their spatial configuration at birth. The UWPs population may result from a cascade fragmentation scenario of the natal molecular core. They could be the older counterparts, to the 0.5 Myr prestellar cores/Class 0 multiple objects observed at radio/millimeter wavelengths (Tobin et al 2010, 2016) and the precursors of the large number of UWPs (10–100 kAU) recently identified in older moving groups (Floriano-Alonso et al, 2015 ; Elliot et al 2016). The NESTs may result from the gravitational collapse of a gas clump that fragments to give a tight collection of stars within few millions years.This project has been partly supported by the StarFormMapper project funded by the European Union's Horizon 2020 Research and Innovation Action (RIA) program under grant agreement number 687528.
From Titan’s tholins to Titan’s aerosols: Isotopic study and chemical evolution at Titan’s surface
NASA Astrophysics Data System (ADS)
Nguyen, Mai-Julie; Raulin, François; Coll, Patrice; Derenne, Sylvie; Szopa, Cyril; Cernogora, Guy; Israël, Guy; Bernard, Jean-Michel
2008-07-01
In the present work, we focused on the possible isotopic fractionation of carbon during the processes involved in the formation of Titan’s tholins. We present the first results obtained on the 12C/13C isotopic ratios measured on Titan’s tholins synthesized in laboratory with cold plasma discharges. Measurements of isotopic ratio 12C/13C, done both on tholins and on the initial gas mixture (N2:CH4 (98:2)) used to produce them, do not show any evident deficit or enrichment in 13C relatively to 12C in the synthesized tholins, compared to the initial gas mixture. This observation allows to go further in the analyses of the ACP experiment data, including part of the Cassini Huygens mission. We also focused on the chemical evolution of the aerosols at Titan surface by studying species coming from acid hydrolysis treatment of Titan’s tholins. Preliminary results show a wide diversity of chemical families, going from carboxylic acids to amino acids. Advanced studies could bring at short-term clues on the still unidentified mixture that induces the decrease of the reflectivity as measure by the DISR instrument [Tomasko, M.G., Archinal, B., Becker, T., Bézard, B., Bushroe, M., Combes, M., Cook, D., Coustenis, A., de Bergh, C., Dafoe, L.E., Doose, L., Douté, S., Eibl, A., Engel, S., Gliem, F., Grieger, B., Holso, K., Howington-Kraus, E., Karkoschka, E., Keller, H.U., Kirk, R., Kramm, R., Küppers, M., Lanagan, P., Lellouch, E., Lemmon, M., Lunine, J., McFarlane, E., Moores, J., Prout, G.M., Rizk, B., Rosiek, M., Rueffer, P., Schröder, S.E., Schmitt, B., See, C., Smith, P., Soderblom, L., Thomas, N., West, R. Rain, winds and haze during the Huygens probe’s descent to Titan’s surface. Nature 438(7069), 765 778, 2005]. At longer-term it could allow to better understand the possible chemical evolution of the Titan’s aerosols after falling down at the surface when brought into contact with water.
[Sciatica. From stretch rack to microdiscectomy].
Gruber, P; Böni, T
2015-12-01
In ancient times as well as in the Middle Ages treatment options for discogenic nerve compression syndrome were limited and usually not very specific because of low anatomical and pathophysiological knowledge. The stretch rack (scamnum Hippocratis) was particularly prominent but was widely used as a therapeutic device for very different spinal disorders. Since the beginning of the nineteenth century anatomical knowledge increased and the advances in the fields of asepsis, anesthesia and surgery resulted in an increase in surgical interventions on the spine. In 1908 the first successful lumbar discectomy was initiated and performed by the German neurologist Heinrich O. Oppenheim (1858-1919) and the surgeon Fedor Krause (1857-1937); however, neither recognized the true pathological condition of discogenic nerve compression syndrome. With the landmark report in the New England Journal of Medicine in 1934, the two American surgeons William Jason Mixter (1880-1958) and Joseph Seaton Barr (1901-1963) finally clarified the pathomechanism of lumbar disc herniation and furthermore, propagated discectomy as the standard therapy. Since then interventions on intervertebral discs rapidly increased and the treatment options for lumbar disc surgery quickly evolved. The surgical procedures changed over time and were continuously being refined. In the late 1960s the surgical microscope was introduced for spinal surgery by the work of the famous neurosurgeon Mahmut Gazi Yasargil and his colleague Wolfhard Caspar and so-called microdiscectomy was introduced. Besides open discectomy other interventional techniques were developed to overcome the side effects of surgical procedures. In 1964 the American orthopedic surgeon Lyman Smith (1912-1991) introduced chemonucleolysis, a minimally invasive technique consisting only of a cannula and the proteolytic enzyme chymopapain, which is injected into the disc compartment to dissolve the displaced disc material. In 1975 the Japanese orthopedic surgeon Sadahisa Hijikata described percutaneous discectomy for the first time, which was a further minimally invasive surgical technique. Further variants of minimally invasive surgical procedures, such as percutaneous laser discectomy in 1986 and percutaneous endoscopic microdiscectomy in 1997, were also introduced; however, open discectomy, especially microdiscectomy remains the therapeutic gold standard for lumbar disc herniation.
Thomas, Melissa M.; Wang, David C.; D'Souza, Donna M.; Krause, Matthew P.; Layne, Andrew S.; Criswell, David S.; O'Neill, Hayley M.; Connor, Michael K.; Anderson, Judy E.; Kemp, Bruce E.; Steinberg, Gregory R.; Hawke, Thomas J.
2014-01-01
AMP-activated protein kinase (AMPK) is a master regulator of metabolism. While muscle-specific AMPK β1β2 double-knockout (β1β2M-KO) mice display alterations in metabolic and mitochondrial capacity, their severe exercise intolerance suggested a secondary contributor to the observed phenotype. We find that tibialis anterior (TA), but not soleus, muscles of sedentary β1β2M-KO mice display a significant myopathy (decreased myofiber areas, increased split and necrotic myofibers, and increased centrally nucleated myofibers. A mitochondrial- and fiber-type-specific etiology to the myopathy was ruled out. However, β1β2M-KO TA muscles displayed significant (P<0.05) increases in platelet aggregation and apoptosis within myofibers and surrounding interstitium (P<0.05). These changes correlated with a 45% decrease in capillary density (P<0.05). We hypothesized that the β1β2M-KO myopathy in resting muscle resulted from impaired AMPK-nNOSμ signaling, causing increased platelet aggregation, impaired vasodilation, and, ultimately, ischemic injury. Consistent with this hypothesis, AMPK-specific phosphorylation (Ser1446) of nNOSμ was decreased in β1β2M-KO compared to wild-type (WT) mice. The AMPK-nNOSμ relationship was further demonstrated by administration of 5-aminoimidazole-4-carboxamide 1-β-d-ribofuranoside (AICAR) to β1β2-MKO muscles and C2C12 myotubes. AICAR significantly increased nNOSμ phosphorylation and nitric oxide production (P<0.05) within minutes of administration in WT muscles and C2C12 myotubes but not in β1β2M-KO muscles. These findings highlight the importance of the AMPK-nNOSμ pathway in resting skeletal muscle.—Thomas, M. M., Wang, D. C., D'Souza, D. M., Krause, M. P., Layne, A. S., Criswell, D. S., O'Neill, H. M., Connor, M. K., Anderson, J. E., Kemp, B. E., Steinberg, G. R., and Hawke, T. J. Muscle-specific AMPK β1β2-null mice display a myopathy due to loss of capillary density in nonpostural muscles. PMID:24522207
Crews, Sarah C
2011-01-01
The spider genus Selenops Latreille, 1819 occurs in both the Old World and New World tropics and subtropics and contains nearly half of the species in the family Selenopidae Simon, 1897. In this paper the members of the genus Selenops found in North America, Central America, and on islands of the Caribbean are revised, excluding Cuban endemics. No taxonomic changes are currently made to the species from the southwestern United States. In total, 21 new species are described, including Selenops arikoksp. n., Selenops chamelasp. n., Selenops amonasp. n., Selenops bawekasp. n., Selenops bocacanadensissp. n., Selenops enriquillosp. n, Selenops ixchelsp. n., Selenops huetocatlsp. n., Selenops kalinagosp. n., Selenops oviedosp. n., Selenops morrosp. n., Selenops deniasp. n., Selenops duansp. n., Selenops malinalxochitlsp. n., Selenops oricuajosp. n., Selenops petenajtoysp. n., Selenops guerrerosp. n., Selenops makimakisp. n., Selenops souligasp. n., Selenops wilmotorumsp. n., and Selenops wilsonisp. n. Six species names were synonymized: Selenops lunatus Muma, 1953 syn. n. =Selenops candidus Muma, 1953; Selenops tehuacanus Muma 1953 syn. n., Selenops galapagoensis Banks, 1902 syn. n. and Selenops vagabundus Kraus, 1955 syn. n. = Selenops mexicanus Keyserling, 1880; Selenops santibanezi Valdez-Mondragón, 2010 syn. n. = Selenops nigromaculatus Keyserling, 1880; and Selenops salvadoranus Chamberlin, 1925 syn. n. = Selenops bifurcatus Banks, 1909. Lectotypes are designated for the following three species: Selenops marginalis F. O. Pickard-Cambridge, 1900 (♂), Selenops morosus Banks, 1898 (♂), and Selenops mexicanus Keyserling, 1880 (♀). The female neotype is designated for Selenops aissus Walckenaer, 1837. The males of Selenops bani Alayón-García, 1992 and Selenops marcanoi Alayón-García, 1992 are described for the first time, and the females of Selenops phaselus Muma, 1953 and Selenops geraldinae Corronca, 1996 are described for the first time. Almost all species are redescribed, barring Cuban endemics and a few species recently described. New illustrations are provided, including those of the internal female copulatory organs, many of which are illustrated for the first time. A key to species is also provided as are new distributional records.
Magnetic fields in spiral galaxies
NASA Astrophysics Data System (ADS)
Krause, Marita
2015-03-01
The magnetic field structure in edge-on galaxies observed so far shows a plane-parallel magnetic field component in the disk of the galaxy and an X-shaped field in its halo. The plane-parallel field is thought to be the projected axisymmetric (ASS) disk field as observed in face-on galaxies. Some galaxies addionionally exhibit strong vertical magnetic fields in the halo right above and below the central region of the disk. The mean-field dynamo theory in the disk cannot explain these observed fields without the action of a wind, which also probably plays an important role to keep the vertical scale heights constant in galaxies of different Hubble types and star formation activities, as has been observed in the radio continuum: At λ6 cm the vertical scale heights of the thin disk and the thick disk/halo in a sample of five edge-on galaxies are similar with a mean value of 300 +/- 50 pc for the thin disk and 1.8 +/- 0.2 kpc for the thick disk (a table and references are given in Krause 2011) with our sample including the brightest halo observed so far, NGC 253, with strong star formation, as well as one of the weakest halos, NGC 4565, with weak star formation. If synchrotron emission is the dominant loss process of the relativistic electrons the outer shape of the radio emission should be dumbbell-like as has been observed in several edge-on galaxies like e.g. NGC 253 (Heesen et al. 2009) and NGC 4565. As the synchrotron lifetime t syn at a single frequency is proportional to the total magnetic field strength B t -1.5, a cosmic ray bulk speed (velocity of a galactic wind) can be defined as v CR = h CR /t syn = 2 h z /t syn , where h CR and h z are the scale heights of the cosmic rays and the observed radio emission at this freqnency. Similar observed radio scale heights imply a self regulation mechanism between the galactic wind velocity, the total magnetic field strength and the star formation rate SFR in the disk: v CR ~ B t 1.5 ~ SFR ~ 0.5 (Niklas & Beck 1997).
[Clinical characteristics of 4 cases of scleritis associated with systemic lupus erythematosus].
Wang, L; Yang, Y; Jia, Y; Miao, H; Zhou, Y S; Zhang, X Y
2016-12-18
Episcleritis and scleritis are relatively rare ocular diseases, which are commonly associated with rheumatic diseases including systemic lupus erythematosus (SLE). To investigate clinical and laboratory features of SLE-associated episcleritis and scleritis, we now report 4 cases of inpatients who were diagnosed with episcleritis or scleritis secondary to SLE from September 2005 to July 2016 in the Department of Rheumatology and Immunology in Peking University People's Hospital. Demographic, clinical and laboratory characteristics were summarized together with the treatment regimen and the prognosis; the literature was reviewed. There were 3 female and 1 male patients. The average age was (49.0±23.8) years and the mean duration of SLE at the onset of episcleritis or scleritis was (2.1±1.4) years. In addition to the eye involvement, the patients had mucocutaneous manifestations, serositis, lupus nephritis and interstitial pneumonia simultaneously; in the past, 1 patient experienced arthritis, 2 presented Raynaud's phenomenon, and 2 had hematologic involvement. All the patients had antinuclear antibody (ANA) of high titer. The anti double-stranded DNA (ds-DNA) antibody titers were increased in 2 patients. Three patients had positive anti-nucleosome antibody (ANuA) while the other 1 patient did not test it. The complement levels were decreased in 3 patients. The systemic lupus erythematosus disease activity index (SLEDAI) scores were more than 4 points in all the patients (ranging from 7-16), suggesting active disease. Ocular symptoms included pain, redness of the eye and tears. Ophthalmic examinations revealed 3 cases of episcleritis and 1 case of scleritis. Among the 4 patients, 2 patients experienced ocular complications including decrease in vision and uveitis. All the patients were treated with systemic corticosteroids combined with hydroxycloroquine; 3 patients were treated with immunosuppressants (cyclophosphamide in 2 patients and leflunomide in 1 patient). All of the 4 patients received topical steroid and 1 patient received periocular injection of triamcinolone acetonide; 1 patient received topical nonsteroidal anti-inflammatory drug (NSAID).No recurrence of episcleritis or scleritis was observed during the follow-ups. As a conclusion, scleritis and episcleritis, although uncommon, may occur in patients with autoimmune rheumatic diseases including SLE. The occurrence of episcleritis and scleritis may suggest active disease of SLE. Ocular complications need to be aware of in the patients. Prompt diagnosis and treatment was associated with good visual outcomes in the follow-ups.
NASA Astrophysics Data System (ADS)
Holden, Peter; Lanc, Peter; Ireland, Trevor R.; Harrison, T. Mark; Foster, John J.; Bruce, Zane
2009-09-01
The identification and retrieval of a large population of ancient zircons (>4 Ga; Hadean) is of utmost priority if models of the early evolution of Earth are to be rigorously tested. We have developed a rapid and accurate U-Pb zircon age determination protocol utilizing a fully automated multi-collector ion microprobe, the ANU SHRIMP II, to screen and date these zircons. Unattended data acquisition relies on the calibration of a digitized sample map to the Sensitive High Resolution Ion MicroProbe (SHRIMP) sample-stage co-ordinate system. High precision positioning of individual grains can be produced through optical image processing of a specified mount location. The focal position of the mount can be optimized through a correlation between secondary-ion steering and the spot position on the target. For the Hadean zircon project, sample mounts are photographed and sample locations (normally grain centers) are determined off-line. The sample is loaded, reference points calibrated, and the target positions are then visited sequentially. In SHRIMP II multiple-collector mode, zircons are initially screened (ca. 5 s data acquisition) through their 204Pb corrected 207Pb/206Pb ratio; suitable candidates are then analyzed in a longer routine to obtain better measurement statistics, U/Pb, and concentration data. In SHRIMP I and SHRIMP RG, we have incorporated the automated analysis protocol to single-collector measurements. These routines have been used to analyze over 100,000 zircons from the Jack Hills quartzite. Of these, ca. 7%, have an age greater than 3.8 Ga, the oldest grain being 4372 +/- 6 Ma (2[sigma]), and this age is part of a group of analyses around 4350 Ma which we interpret as the age when continental crust first began to coalesce in this region. In multi-collector mode, the analytical time taken for a single mount with 400 zircons is approximately 6 h; whereas in single-collector mode, the analytical time is ca. 17 h. With this productivity, we can produce significant numbers of zircons for statistically limited studies including correlations between age and morphology, mineral-inclusion paragenesis, as well as isotopic studies including Hf and O isotopic compositions, Pu-Xe, and Sm-Nd isotopes.
GSKY: A scalable distributed geospatial data server on the cloud
NASA Astrophysics Data System (ADS)
Rozas Larraondo, Pablo; Pringle, Sean; Antony, Joseph; Evans, Ben
2017-04-01
Earth systems, environmental and geophysical datasets are an extremely valuable sources of information about the state and evolution of the Earth. Being able to combine information coming from different geospatial collections is in increasing demand by the scientific community, and requires managing and manipulating data with different formats and performing operations such as map reprojections, resampling and other transformations. Due to the large data volume inherent in these collections, storing multiple copies of them is unfeasible and so such data manipulation must be performed on-the-fly using efficient, high performance techniques. Ideally this should be performed using a trusted data service and common system libraries to ensure wide use and reproducibility. Recent developments in distributed computing based on dynamic access to significant cloud infrastructure opens the door for such new ways of processing geospatial data on demand. The National Computational Infrastructure (NCI), hosted at the Australian National University (ANU), has over 10 Petabytes of nationally significant research data collections. Some of these collections, which comprise a variety of observed and modelled geospatial data, are now made available via a highly distributed geospatial data server, called GSKY (pronounced [jee-skee]). GSKY supports on demand processing of large geospatial data products such as satellite earth observation data as well as numerical weather products, allowing interactive exploration and analysis of the data. It dynamically and efficiently distributes the required computations among cloud nodes providing a scalable analysis framework that can adapt to serve large number of concurrent users. Typical geospatial workflows handling different file formats and data types, or blending data in different coordinate projections and spatio-temporal resolutions, is handled transparently by GSKY. This is achieved by decoupling the data ingestion and indexing process as an independent service. An indexing service crawls data collections either locally or remotely by extracting, storing and indexing all spatio-temporal metadata associated with each individual record. GSKY provides the user with the ability of specifying how ingested data should be aggregated, transformed and presented. It presents an OGC standards-compliant interface, allowing ready accessibility for users of the data via Web Map Services (WMS), Web Processing Services (WPS) or raw data arrays using Web Coverage Services (WCS). The presentation will show some cases where we have used this new capability to provide a significant improvement over previous approaches.
VizieR Online Data Catalog: Sloan i follow-up light curves of HATS-18 (Penev+, 2016)
NASA Astrophysics Data System (ADS)
Penev, K.; Hartman, J. D.; Bakos, G. A.; Ciceri, S.; Brahm, R.; Bayliss, D.; Bento, J.; Jordan, A.; Csubry, Z.; Bhatti, W.; de Val-Borro, M.; Espinoza, N.; Zhou, G.; Mancini, L.; Rabus, M.; Suc, V.; Henning, T.; Schmidt, B.; Noyes, R. W.; Lazar, J.; Papp, I.; Sari, P.
2017-02-01
The star HATS-18 was observed by HATSouth instruments between UT 2011 April 18 and UT 2013 July 21 using the HS-2, HS-4, and HS-6 units at the Las Campanas Observatory in Chile, the High Energy Spectroscopic Survey (H.E.S.S.) site in Namibia, and Siding Spring Observatory (SSO) in Australia, respectively. A total of 5372, 3758, and 4008 images of HATS-18 were obtained with HS-2, HS-4, and HS-6, respectively. The observations were obtained through a Sloan r filter with an exposure time of 240s. We obtained follow-up light curves of HATS-18 using the Las Cumbres Observatory Global Telescope (LCOGT) 1m telescope network. An ingress was observed on UT 2015 July 18 with the SBIG camera and a Sloan i filter on the 1m at the South African Astronomical Observatory (SAAO). A total of 33 images were collected at a median cadence of 201s. A full transit was observed on UT 2016 January 22 with the sinistro camera and a Sloan i filter on the 1m at Cerro Tololo Inter-American Observatory. A total of 61 images were collected at a median cadence of 219s. For the record, we also note that a full transit was observed on UT 2016 January 3 with the SBIG camera on the 1m at SAAO; however, due to tracking and weather problems, we were unable to extract high-precision photometry from these images, and therefore do not include these data in our analysis. The data are available in Table1. Spectroscopic follow-up observations of HATS-18 were carried out with WiFeS on the Australian National University (ANU) 2.3m telescope and with the Fiber-fed Extended Range Optical Spectrograph (FEROS) on the MPG 2.2m. A total of three spectra were obtained with WiFeS between UT 2015 February 28 and UT 2015 March 2, two at a resolution of R=Δλ/λ=7000, and one at R=3000. We obtained six R=48000 spectra with FEROS between UT 2015 June 12 and UT 2015 June 20. The data are provided in Table2. (2 data files).
Atmospheric 21Ne abundance determined by the Helix-MC Plus mass spectrometer
NASA Astrophysics Data System (ADS)
Honda, M.; Zhang, X.; Phillips, D.; Hamilton, D.; Deerberg, M.; Schwieters, J. B.
2014-12-01
Analyses of noble gas isotopes by multi-collector, high resolution mass spectrometry have the potential to revolutionise applications in the cosmo-geo-sciences. The Helix-MC Plus noble gas mass spectrometer installed at the Australian National University (ANU) is equipped with unique high mass resolution collectors [mass resolution (MR): ~1,800 and mass resolving power (MRP): ~8,000], including fixed axial (Ax), adjustable high mass (H2) and adjustable low mass (L2) detectors. The high mass resolution of the L2, Ax and H2 collectors permits complete separation of 20Ne (measured on L2 detector) from doubly charged interfering 40Ar (required MR of 1,777), 1H19F (MR = 1450), 1H218O (MR = 894) and partial separation of the 21Ne peak (on Ax detector) from interfering 20Ne1H (MR = 3,271), and 22Ne (on H2 detector) from interfering doubly charged CO2 (MR = 6,231). Because of the high MRP of ~8,000, 21Ne can be measured, essentially without interference from 20Ne1H, by setting the magnet position on a 20Ne1H interference-free position. This capability provides an important opportunity to re-evaluate the 21Ne abundance in the atmosphere. Our analyses demonstrate that 20Ne1H contributes ~4% to atmospheric 21Ne measurements, with the corresponding production ratio of 20Ne1H to 20Ne being ~1E-4. We calculate a new atmospheric 21Ne/20Ne ratio of 0.00287 relative to an atmospheric 22Ne/20Ne ratio of 0.102; this new value is distinctly lower than the current IUPAC recommended 21Ne/20Ne value of 0.00298. There are several significant implications ensuing from the newly determined atmospheric 21Ne abundance. For example, in the area of Earth sciences the most critical issue relates to cosmogenic 21Ne surface exposure ages, which involve the calculation of 21Ne concentrations from excess 21Ne, relative to the atmospheric 21Ne/20Ne ratio. For young samples, where cosmogenic 21Ne contents are small and the 21Ne/20Ne ratio is close to the atmospheric value, the revised value could increase cosmogenic 21Ne ages by ~30%.
Isotopic Study of the Mauna Loa Southwest Rift Mile High Section: Hawaiian Mantle Plume Components
NASA Astrophysics Data System (ADS)
Weis, D.; Rhodes, J. M.; Garcia, M. O.
2003-12-01
The new JASON2 ROV was employed to collect 51 samples from a 1.8 km thick submarine landslide scarp along the crest of the southwest rift zone of the Mauna Loa volcano to investigate the nature and history of Hawaiian mantle plume components. The rift zone section records about 400,000 years of eruptive activity, 50% of the volcano's total lifetime, which is comparable to the time-period sampled by the Hawaiian Scientific Drilling Project (HSPD2). Sr, Nd, Pb and Hf isotopes have been analyzed on 14 samples from the "Mile High" section. The range of variation observed falls typically within literature data for the Mauna Loa volcano with 87Sr/86Sr from 0.70368 to 0.70378 and 206Pb/204Pb from 18.16 to 18.26, and is somewhat more radiogenic than most Mauna Loa prehistoric (<31 ka) lavas. In the section, there is a distinct increase in Pb and Sr isotopes, which is also recorded by major and trace element data, at a depth of 1353 m. Isotope ratios continue to increase to the bottom of the section at 2290 m. High precision Pb-Pb isotopic systematics for Mauna Loa lavas do not show the binary mixing trends as also observed in the upper part of the HSDPI pilot hole and contrary to Mauna Kea lavas (Abouchami et al., Chemical Geology 2000). This might imply that the Mauna Loa plume source is more thoroughly mixed than the Mauna Kea source. Most of Mauna Loa isotopic compositions cluster at 18.15-18.20 for 206Pb/204Pb and ˜0.70370 for 87Sr/86Sr, which could be a ubiquitous refractory component in the Hawaiian mantle plume (Rhodes and Weis, Fall AGU 2001). Nevertheless, a more radiogenic plume component with higher 208Pb/204Pb and 208Pb*/206Pb* is clearly present in the lower part of the Mile High section and might be comparable to the Kilauea-like component observed in Mauna Kea lavas in HSDP2 (Blichert-Toft et al., G3 2003). Team members also include: D. Wanless and K. Kolysko, University of Hawaii; H. Guillou, CEA/CNRS, France; M. Kurz and D. Fornari, WHOI; M. Norman and V. Bennett, ANU, Australia; F. Trusdell and S. Schilling, USGS; M. Chapman, Morehead State University; M. Vollinger, University of Massachusetts.
NASA Astrophysics Data System (ADS)
Rhodes, J. M.; Garcia, M. O.; Weis, D.; Trusdell, F. A.; Vollinger, M. J.
2003-12-01
Mauna Loa's southwest rift zone (SWR) extends for 102 km from its summit caldera, at an elevation of 4,170 m above sea level, to submarine depths of over 4,500 m. About 65% of the rift zone is subaerial and 35% submarine. Recent sampling with the Jason II submersible of the `mile-high' (1800 m) Ka Lae submarine landslide scarp and the deepest section of the rift zone, in conjunction with previous submersible and dredge-haul collecting, provides petrological and geochemical understanding of rift zone processes, as well as a record of Mauna Loa's eruptive history extending back about 400 ka. The major and trace element trends of the submarine lavas are remarkably similar to those of historical and young prehistoric lavas (<31 ka) erupted along the subaerial SWR. We take this to imply that magma-forming processes have remained relatively constant over much of the volcano's recorded eruptive history. However, the distribution of samples along these trends has varied, and is correlated with elevation. There are very few picrites (>12% MgO) among the subaerial lavas, and compositions tend to cluster around 6.8-8.0% MgO. In contrast, picritic lavas are extremely abundant in the submarine samples, increasing in frequency with depth, especially below 1200 m. These observations support earlier interpretations that the submarine lavas are derived directly from deeper levels in the magma column, and that magmas from a shallow, steady-state, magma reservoir are of uncommon at these depths. Isotopic ratios of Pb and Sr in the submarine lavas, in conjunction with Nb/Y and Zr/Nb ratios, extend from values that are identical with subaerial historical Mauna Loa lavas to lavas with markedly lower 87Sr/86Sr and higher 206Pb/204Pb isotopic ratios. As yet, we see no correlation with depth or age, but the implications are that, in the past, the plume source of Mauna Loa magmas was more variable than in the last 31 ka, and contained a greater proportion of the Kea component. *Team members also include: H. Guillou, CEA/CNRS, France; M. Kurz and D. Fornari, WHOI; M. Norman and V. Bennett, ANU, Australia; S. Schilling, USGS; M. Chapman, Morehead State University; D. Wanless and K. Kolysko, University of Hawaii.
VizieR Online Data Catalog: Radio haloes in nearby galaxies (Heesen+, 2018)
NASA Astrophysics Data System (ADS)
Heesen, V.; Krause, M.; Beck, R.; Adebahr, B.; Bomans, D. J.; Carretti, E.; Dumke, M.; Heald, G.; Irwin, J.; Koribalski, B. S.; Mulcahy, D. D.; Westmeier, T.; Dettmar, R.-J.
2018-02-01
We present radio continuum observations of 12 nearby (D=2-27Mpc) edge-on galaxies at two different frequencies, namely at 1.4 and 5GHz (one galaxy at 8.5GHz instead of 5GHz). Our sample includes 11 late-type spiral (Sb or Sc) galaxies and one Magellanic-type barred galaxy (SBm), which are all highly inclined (i>=76°). As part of our study we have obtained several additional radio continuum maps. We make these maps publicly available (as well as all the other radio continuum maps in the paper). For 4 galaxies (NGC 55, 253, 891 and 4631) we have used single-dish maps, to correct for the missing zero-spacing flux where necessary. The Effelsberg maps of NGC 253 and 4631 were already presented in Heesen et al. (2009A&A...494..563H) and Mora & Krause (2013A&A...560A..42M), respectively, and the Effelsberg map of NGC 891 was already presented in Dumke (1997, PhD thesis, University of Bonn). We present these maps for completeness. The 4.80-GHz map of NGC 55 obtained with the 64-m Parkes telescope is so far unpublished. Furthermore, we show two maps of NGC 4631 at 1.35 and 1.65GHz observed with the VLA in D- configuration (R. Beck 2016, priv. comm.). The data were observed in August 1996, with 12 h on-source (ID: AG486) and reduced in standard fashion with AIPS. The maps have an angular resolution of 52 arcsec, so that we did not use them in the analysis, but they also show the halo of this galaxy very well. Lastly, we obtained maps of three further edge-on galaxies observed with the VLA (NGC 4157, 4217 and 4634). We reduced the data as described in Section 2, but since we had only one frequency available and no spectral index map, we did not use them in the analysis. The maps of NGC 4157 and 4217 were created by re-reducing archive data (IDs AI23, AF85, AH457 and AS392 for NGC 4157 and ID AM573 for NGC 4217). The map of NGC 4634 was created by using so far unpublished data from the VLA (ID: AD538). (3 data files).
Ecosystem resilience to abrupt late Quaternary change in continental southern Siberia
NASA Astrophysics Data System (ADS)
Harding, Poppy; Mackay, Anson; Bezrukova, Elena; Shchetnikov, Alexander
2017-04-01
Quaternary climate variability is dominated by long term orbital forcing along with abrupt sub-Milankovitch events on the scales of millennia to centuries, driven by internal feedback mechanisms, volcanic forcing and fluctuating solar activity. Although these are well documented in the North Atlantic region, their expression is poorly understood in Siberia, particularly in relation to abrupt climatic events. Siberia has the world's highest level of continentality offering an opportunity to study changes remote from oceanic influences and improving understanding of interactions between the Siberian High and other atmospheric systems including the Aleutian Low, Arctic oscillation and Icelandic Low1 and ENSO2. Understanding of palaeoenvironmental change in Siberia is essential due to the region's high sensitivity to climatic change, with warming rates considerably higher than the global average over the past 50 years3, triggering significant environmental changes, including permafrost degradation, shifts in the forest-steppe biome, increases in forest fires and warming of seasonally ice-covered lakes. Additionally, the region provides essential palaeoenvironmental context for early hominins, for example at globally important sites such as Denisova cave4, and megafauna extinctions5. This presentation outlines ongoing work at Lake Baunt, SE Siberia including: key quaternary climate forcings, the site and its regional context, the key methods and preliminary results. These include a dated record back to ˜30ka BP (based on multiple 14C dates and Bayesian age modelling), multiproxy indicators of palaeoproductivity (e.g. biogenic silica and diatom analyses) and lake mixing regimes (inferred from diatom analyses). Together these highlight several key Quaternary fluctuations potentially correlated to events recorded in Greenland Ice Cores (GS2, GS2.1, GI1, GS1), and these are considered against key Quaternary records including those from nearby Lake Baikal and Hulu Cave in east China. Our analyses suggest that teleconnections between the Siberian High and the East Asian monsoon are also significant for this study, with Lake Baunt showing a relationship between productivity and variability in strength of the Siberian High. References: 1. Tubi, A. & Dayan, U. (2013). Int. J. Climatol. 33, 1357-1366. 2. Park, T.-W. et al. (2014). Clim. Dyn. 45, 1207-1217. 3. Tingley, M. P. & Huybers, P. (2013). Nature 496, 201-5. 4. Krause, J. et al.. (2010). Nature 464, 894-7. 5. Stuart, A. J. et al. (2004). Nature 431, 684-9.
A history of lumbar disc herniation from Hippocrates to the 1990s.
Truumees, Eeric
2015-06-01
In ancient times, a supernatural understanding of the syndrome of lumbar radiculopathy often involved demonic forces vexing the individual with often crippling pain. The ancient Greeks and Egyptians began to take a more naturalistic view and, critically, suspected a relationship between lumbar spinal pathology and leg symptoms. Relatively little then changed for those with sciatica until the classic works by Cotugno and Kocher arrived in the late 18th century. Early lumbar canal explorations were performed in the late 1800s and early 1900s by MacEwen, Horsley, Krause, Taylor, Dandy, and Cushing, among others. In these cases, when compressive pathologies were found and removed, the lesions typically were (mis-)identified as enchondromas or osteochondritis dissecans. To better understand the history, learn more about the first treatments of lumbar disc herniation, and evaluate the impact of the early influences on modern spine practice, searches of PubMed and Embase were performed using the search terms discectomy, medical history, lumbar spine surgery, herniated disc, herniated nucleus pulposus, sciatica, and lumbar radiculopathy. Additional sources were identified from the reference lists of the reviewed papers. Many older and ancient sources including De Ischiade Nervosa are available in English translations and were used. When full texts were not available, English abstracts were used. The first true, intentional discectomy surgery was performed by Mixter and Barr in 1932. Early on, a transdural approach was favored. In 1938, Love described the intralaminar, extradural approach. His technique, although modified with improved lighting, magnification, and retractors, remains a staple approach to disc herniations today. Other modalities such as chymopapain have been investigated. Some remain a part of the therapeutic armamentarium, whereas others have disappeared. By the 1970s, CT scanning after myelography markedly improved the clinical evaluation of patients with lumbar disc herniation. In this era, use of discectomy surgery increased rapidly. Even patients with very early symptoms were offered surgery. Later work, especially by Weber and Hakelius, showed that many patients with lumbar disc herniation would improve without surgical intervention. In the ensuing decades, the debate over operative indications and timing continued, reaching another pivotal moment with the 2006 publication of the initial results of Spine Patient Outcomes Research Trial.
The Mineral Collection of the University of Michigan: its History and Future
NASA Astrophysics Data System (ADS)
Stefano, C. J.; Ewing, R. C.; Erwin, K.
2012-12-01
The mineral collection at the University of Michigan is among the oldest and finest in the Great Lakes region. The collection was created in 1838 with the purchase, under Douglass Houghton, one of the first professors at the University of Michigan, of 2,600 specimens, largely of European origin, from Baron Louis von Lederer of Vienna. This was one of the first major purchases by the Board of Regents. The collection was actively curated and continued to grow under the direction of Edward H. Kraus, one of the founders of the Mineralogical Society of America and the Chair of the then separate Department of Mineralogy. The collection is the repository for specimens collected by Douglass Houghton, as well as specimens collected during the first geological survey of Michigan. Specimens from Michigan's Keweenaw copper district are of exceptional quality, mainly due to the world-class specimens donated by then Regent L. L. Hubbard between 1917 and the mid-1920s. There is also a significant suite of fine Sicilian sulfur specimens collected during the Ph.D. research of Professor Walter F. Hunt. Other important suites include the Stuart H. Perry Meteorite collection, the Frederick S. Stearns gemstone collection, and a suite of Antarctic rock samples collected during the Byrd expedition in 1928-30. The collection also has a wide variety of worldwide specimens, mostly of reference quality, although there are several hundred excellent to world class pieces that do not fit into the core suites. Overall, the collection contains approximately 15,000 mineral specimens, about 1,000 meteorites, and several thousand gemstones and related materials. Although the collection continued to be an important part of the teaching and research efforts after the Departments of Mineralogy and Geology were merged in 1961, the collection was little used and without active curation through the latter half of the 20th Century. Recently, the University has initiated an inventory process prior to determining the fate of the Collection. The range of options are driven by the research needs of the Department, which have changed substantially in recent years, as well as the need for financial support and space in order to properly curate and preserve the collection. A major issue is how one weighs the historical, scientific and aesthetic value of such a collection against the mission and financial demands of the University.
Crews, Sarah C.
2011-01-01
Abstract The spider genus Selenops Latreille, 1819 occurs in both the Old World and New World tropics and subtropics and contains nearly half of the species in the family Selenopidae Simon, 1897. In this paper the members of the genus Selenops found in North America, Central America, and on islands of the Caribbean are revised, excluding Cuban endemics. No taxonomic changes are currently made to the species from the southwestern United States. In total, 21 new species are described, including Selenops arikok sp. n., Selenops chamela sp. n., Selenops amona sp. n., Selenops baweka sp. n., Selenops bocacanadensis sp. n., Selenops enriquillo sp. n, Selenops ixchel sp. n., Selenops huetocatl sp. n., Selenops kalinago sp. n., Selenops oviedo sp. n., Selenops morro sp. n., Selenops denia sp. n., Selenops duan sp. n., Selenops malinalxochitl sp. n., Selenops oricuajo sp. n., Selenops petenajtoy sp. n., Selenops guerrero sp. n., Selenops makimaki sp. n., Selenops souliga sp. n., Selenops wilmotorum sp. n., and Selenops wilsoni sp. n. Six species names were synonymized: Selenops lunatus Muma, 1953 syn. n. = Selenops candidus Muma, 1953; Selenops tehuacanus Muma 1953 syn. n., Selenops galapagoensis Banks, 1902 syn. n. and Selenops vagabundus Kraus, 1955 syn. n. = Selenops mexicanus Keyserling, 1880; Selenops santibanezi Valdez-Mondragón, 2010 syn. n. = Selenops nigromaculatus Keyserling, 1880; and Selenops salvadoranus Chamberlin, 1925 syn. n. = Selenops bifurcatus Banks, 1909. Lectotypes are designated for the following three species: Selenops marginalis F. O. Pickard-Cambridge, 1900 (♂), Selenops morosus Banks, 1898 (♂), and Selenops mexicanus Keyserling, 1880 (♀). The female neotype is designated for Selenops aissus Walckenaer, 1837. The males of Selenops bani Alayón-García, 1992 and Selenops marcanoi Alayón-García, 1992 are described for the first time, and the females of Selenops phaselus Muma, 1953 and Selenops geraldinae Corronca, 1996 are described for the first time. Almost all species are redescribed, barring Cuban endemics and a few species recently described. New illustrations are provided, including those of the internal female copulatory organs, many of which are illustrated for the first time. A key to species is also provided as are new distributional records. PMID:21852919
NASA Astrophysics Data System (ADS)
Geipele, I.; Staube, T.; Ciemleja, G.; Zeltins, N.; Ekmanis, Yu.
2015-08-01
The publication comprises the results from the practical scientific investigation to define the profile and distinctions of the Latvian innovative multifunctional material manufacturing industry. The research is carried out by a holistic approach, including expert interviews, qualitative analysis of the official register data, practical survey, and financial data analysis. The paper seeks to give the detailed data on a technological profile of the mentioned representative companies, if there is a synergy or tough competition in the Latvian market. The current research is topical, because it is unique and does not have analogues in Latvia, and the research is timely due to correspondence with recently stated Research and Innovation Strategies for Smart Specialisation in Latvia. The main findings are associated with recognition of the factors that make impact on commercialisation of the finished goods, obtained financial results and planned directions of development of the respondent companies. Publikācija sniedz veiktā zinātniski praktiskā pētījuma rezultātus, kura ietvaros tika noteikts Latvijas inovatīvu daudzfunkcionālo materiālu ražotāju darbības profils un identitāte. Pētījumā tika izmantota kompleksās analīzes metode, kas ietvēra ekspertu intervijas, uzņēmumu oficiāli reģistrēto datu kvalitatīvo analīzi, zinātniski praktisko aptauju, kā arī pētāmo uzņēmumu finanšu darbības rezultātu analīzi. Zinātniskais darbs sniedz izsmeļošu informāciju par mērķa uzņēmumu tehnoloģisko profilu un pēta, vai Latvijas mērķa ražošanas nozarē ir sinerģijas vai sīvās konkurences pazīmes. Šim zinātniskajam pētījumam ir noteikta aktualitāte saskaņā ar tā unikalitāti Latvijas valsts mērogā un atbilstība Viedās specializācijas stratēģijai. Pētījuma galvenie secinājumi ir saistīti ar uzņēmumu produkcijas komercializācijas ietekmējošo faktoru apzināšanu, sasniegtajiem finansiālajiem rezultātiem un plānotajiem attīstības virzieniem.
NASA Astrophysics Data System (ADS)
Purss, Matthew; Lewis, Adam; Edberg, Roger; Ip, Alex; Sixsmith, Joshua; Frankish, Glenn; Chan, Tai; Evans, Ben; Hurst, Lachlan
2013-04-01
Australia's Earth Observation Program has downlinked and archived satellite data acquired under the NASA Landsat mission for the Australian Government since the establishment of the Australian Landsat Station in 1979. Geoscience Australia maintains this archive and produces image products to aid the delivery of government policy objectives. Due to the labor intensive nature of processing of this data there have been few national-scale datasets created to date. To compile any Earth Observation product the historical approach has been to select the required subset of data and process "scene by scene" on an as-needed basis. As data volumes have increased over time, and the demand for the processed data has also grown, it has become increasingly difficult to rapidly produce these products and achieve satisfactory policy outcomes using these historic processing methods. The result is that we have been "drowning in a sea of uncalibrated data" and scientists, policy makers and the public have not been able to realize the full potential of the Australian Landsat Archive and its value is therefore significantly diminished. To overcome this critical issue, the Australian Space Research Program has funded the "Unlocking the Landsat Archive" (ULA) Project from April 2011 to June 2013 to improve the access and utilization of Australia's archive of Landsat data. The ULA Project is a public-private consortium led by Lockheed Martin Australia (LMA) and involving Geoscience Australia (GA), the Victorian Partnership for Advanced Computing (VPAC), the National Computational Infrastructure (NCI) at the Australian National University (ANU) and the Cooperative Research Centre for Spatial Information (CRC-SI). The outputs from the ULA project will become a fundamental component of Australia's eResearch infrastructure, with the Australian Landsat Archive hosted on the NCI and made openly available under a creative commons license. NCI provides access to researchers through significant HPC supercomputers, cloud infrastructure and data resources along with a large catalogue of software tools that make it possible to fully explore the potential of this data. Under the ULA Project, Geoscience Australia has developed a data-intensive processing workflow on the NCI. This system has allowed us to successfully process 11 years of the Australian Landsat Archive (from 2000 to 2010 inclusive) to standardized well-calibrated and sensor independent data products at a rate that allows for both bulk data processing of the archive and near-realtime processing of newly acquired satellite data. These products are available as Optical Surface Reflectance 25m (OSR25) and other derived products, such as Fractional Cover.
Proceedings of the 6th European VLBI Network Symposium
NASA Astrophysics Data System (ADS)
Ros, Eduardo; Porcas, Richard W.; Lobanov, Andrei P.; Zensus, J. Anton
This volume contains the papers presented at the 6th Symposium of the European VLBI Network, held in Bonn on 25-28 June 2002. The initial aim of these biennial gatherings of European VLBI practitioners was to review in a timely manner new results and technical developments related to Very Long Baseline Interferometry. Now, however, interest and participation in the EVN Symposia reaches far beyond Europe, reflecting the fact that scientific research and development programs are carried out to a high degree in international and often truly global collaborations. More than 120 scientists from around the world registered for participation in the Symposium. The Symposium was hosted by the Max-Planck-Institut für Radioastronomie and was held at the Gustav Stresemann Institut. In addition to the scientific sessions and poster presentations, the program included an EVN Users Meeting, an MPIfR versus Rest-of-the-World football match (highly appropriate given the competing World Cup event!), a visit to the MPIfR's 100m radio telescope in Effelsberg, and a Conference Dinner held in the nearby old walled town of Bad Müunstereifel. To maximize the usefulness of these proceedings (and possibly as a daring precedent) the Editors decided to demand the written versions of talks and posters and to complete the editorial work before the meeting, and to deliver the book to the participants at the beginning of the Symposium. We thank the authors for their cooperation in delivering publication-ready electronic manuscripts and for meeting the strict deadlines. It is highly gratifying that only a handful of the 100 presentations are not represented in this volume. The editors have made minor changes to some of the contributions in order to improve readability, and take responsibility for any errors arising from these changes. Besides the authors, many individuals have contributed to the preparation of the meeting and its proceedings. In addition to many members of the MPIfR staff, we especially wish to thank: W. Alef, U. Bach, E. Fürst, E. Fingas, L. Fuhrmann, L. Gurvits, N. Junkes, M. Kadler, A. Kraus, E. Middelberg, P. Müller, B. Naunheim, J. Schmidt, and R. Schwartz. Financial support for the Symposium came from the Max-Planck-Institut für Radioastronomie, from the 5th Framework Programme of the European Commission (IHP - Infrastructure Cooperation Networks, contract number HPRI-CT-1999-400003), and from the Max Planck Research Prize for International Collaboration.
Dissolved Gases in Seawater and Sediments (Paper 7R0315)
NASA Astrophysics Data System (ADS)
Key, R. M.
1987-07-01
Certainly the most controversial results derived from the study of any dissolved gas concerned oxygen utilization rates in the North Atlantic. Jenkins (1982) estimated a net oxy-gen utilization rate (OUR) for the Beta triangle region of the North Atlantic (apices 26.5°N x 38.5°W, 32.5°N x 30.0°W, and 22.5°N x 28.5°W) of 5.7 moles of oxygen consumed m-2 yr-1 for the zone below 100m. He assumed that the oxygen distribution below the euphotic zone was stationary and steady state and therfore that the in situ oxygen consumption must be balanced by physical transport of oxygen into the area. His estimates were based on measured distributions of dissolved oxygen and the tracers 3He and 3H and a simple model which assumed lateral advection was small. The derived value or OUR was several times higher that previous estimates based on 14C and 15N incubation techniques. The OUR requires a downward flux of carbon from the photic zone of approximately 50 gCm-2yr-1 , which is again much higher that previous results. Jenkins and Goldman (1985) amplified the arguments in a study of seasonal oxygen cycling and primary production based on a ten year time series of measurements from the Panulirus station near Bermuda. Considering insolation, heat budgets and 3He/3H data they estimated a vertically integrated oxygen production rate of 5 Mm-2yr-1 and a subsequent new production of 50 gCm-2yr-1. The results were supported by calculations based on a second order turbulence closure model (Klein and Coste, 1984). These results have been challenged primarily on the basis of the spatial variability of the phenomenon!. Whatever the final outcome Jenkins has clearly demonstrated that the time has come to take a fresh look at oxygen utilization rates and primary productivity given the tools and modelling capabilities now at hand. The TTO data set will go a long way toward providing the necessary data set for the North Atlantic when the analyses are complete. Other studies have dealt with the photooxidative daylight loss of oxygen from near-surface tropical waters (Gieskes and Kraay, 1982), isotopic fractionation between fresh and seawater and the atmosphere (Benson and Krause, 1984) , edge effects on chemistry in the 02 minimum zone (Mullins et al., 1985), and the relationship between oxygen and other biogeochemical properties (Pak, 1984; Blizard and Pak, 1984; Lewitus and Broenkow, 1985).
NASA Astrophysics Data System (ADS)
Wuttke, M. W.; Kessels, W.; Wessling, S.; Han, J.
2007-05-01
Spontaneous combustion is a world wide problem for technical operations in mining, waste disposal and power plant facilities. The principle driving the combustion is every where the same independent of the different reactive materials: Fresh air with the common oxygen content is getting in contact with the reactive material by human operations. The following reaction process produces heat at a usually low but constant rate. The reactive material in operating or abandoned coal mines, heaps of coal, waste or reactive minerals is most times strongly broken or fractured, such that the atmospheric oxygen can deeply penetrate into the porous or fractured media. Because the strongly broken or fractured medium with air filled pores and fractures is often combined with a low thermal conductivity of the bulk material the produced heat accumulates and the temperature increases with time. If the reactivity strongly increases with temperature, the temperature rise accelerates up to the "combustion temperature". Once the temperature is high enough the combustion process is determined by the oxygen transport to the combustion center rather than the chemical reactivity. Spontaneous combustion is thus a self- amplifying process where an initial small variation in the parameters and the starting conditions can create exploding combustion hot spots in an apparently homogenous material. The phenomenon will be discussed by various examples in the context of the German - Sino coal fire project. A temperature monitoring in hot fracture systems documents the strong influence of the weather conditions on the combustion process. Numerical calculations show the sensitivity of the combustion to the model geometries, the boundary conditions and mainly the permeability. The most used fire fighting operations like covering and water injection are discussed. A new method of using saltwater for fire fighting is presented and discussed. References: Kessels, W., Wessling, S., Li, X., and Wuttke, M. W. Numerical element distinction for reactive transport modeling regarding reaction rate. In Proceedings of MODFLOW and MORE 2006: Managing Groundwater Systems, May 21 - 24, 2006, Golden, CO USA (2006). Kessels, W., Wuttke, M. W., Wessling, S., and Li, X. Coal fires between self ignition and fire fighting: Numerical modeling and basic geophysical measurements. In ERSEC Ecological Book Series - 4 on Coal Fire Research (2007). Wessling, S., Litschke, T., Wiegand, J., Schlömer, S., and Kessels, W. Simulating dynamic subsurface coal fires and its applications. In ERSEC Ecological Book Series - 4 on Coal Fire Reserach (2007). Wessling, S., Kessels, W., Schmidt, M., and Krause, U. Investigating dynamic underground coal fires by means of numerical simulation. Geophys. J. Int. (submitted).
NASA Astrophysics Data System (ADS)
Teibe, I.; Bendere, R.; Arina, D.
2013-12-01
In the work, the life-cycle assessment approach is applied to the planning of waste management development in a seaside region (Piejūra) using the Waste Management Planning System (WAMPS) program. In Latvia, the measures to be taken for the climate change mitigation are of utmost importance - especially as related to the WM performance, since a disposal of biodegradable waste presents the primary source of GHG emissions. To reduce the amount of such waste is therefore one of the most significant goals in the State WM plan for 2013-2020, whose adoption is the greatest challenge for municipalities. The authors analyse seven models which involve widely employed biomass processing methods, are based on experimental data and intended for minimising the direct disposal of organic mass at the solid waste landfills. The numerical results obtained evidence that the thermal or biotechnological treatment of organic waste substantially reduces the negative environmental impact of WM practices - by up to 6% as compared with the currently existing. Klimata pārmaiņu samazināšanas pasākumi Latvijā atkritumu saimniecības sektorā ir īpaši svarīgi. jo bioloģiski sadalāmo atkritumu apglabāšana ir viens no būtiskākajiem SEG emisiju avotiem valstī. Pētījumā modelēti virkne sadzīves atkritumu apsaimniekošanas modeļi. kas ietver plašāk izmantotās biomasas pārstrādes metodes un samazina tiešu organiskās masas apglabāšanu cieto sadzīves atkritumu poligonos. Atkritumu apsaimniekošanas modeļu radītās vides ietekmes novērtēšanai izmantota WAMPS (Waste Management Planning System) programma, kas balstīta uz atkritumu apsaimniekošanas procesu dzīves cikla novērtējumu vienā no desmit Latvijas atkritumu apsaimniekošanas reģioniem - Piejūra. Iegūtie kvantitatīvie rezultāti norāda. ka organiskās atkritumu masas pārstrāde un stabilizēšana, izmantojot biotehnoloģijas vai termisko pārstrādi, būtiski samazina atkritumu apsaimniekošanas radīto negatīvo vides ietekmi. līdz pat 6% attiecībā pret esošās atkritumu saimniecības vides ietekmi.
NASA Astrophysics Data System (ADS)
Daniell, James; Simpson, Alanna; Gunasekara, Rashmin; Baca, Abigail; Schaefer, Andreas; Ishizawa, Oscar; Murnane, Rick; Tijssen, Annegien; Deparday, Vivien; Forni, Marc; Himmelfarb, Anne; Leder, Jan
2015-04-01
Over the past few decades, a plethora of open access software packages for the calculation of earthquake, volcanic, tsunami, storm surge, wind and flood have been produced globally. As part of the World Bank GFDRR Review released at the Understanding Risk 2014 Conference, over 80 such open access risk assessment software packages were examined. Commercial software was not considered in the evaluation. A preliminary analysis was used to determine whether the 80 models were currently supported and if they were open access. This process was used to select a subset of 31 models that include 8 earthquake models, 4 cyclone models, 11 flood models, and 8 storm surge/tsunami models for more detailed analysis. By using multi-criteria analysis (MCDA) and simple descriptions of the software uses, the review allows users to select a few relevant software packages for their own testing and development. The detailed analysis evaluated the models on the basis of over 100 criteria and provides a synopsis of available open access natural hazard risk modelling tools. In addition, volcano software packages have since been added making the compendium of risk software tools in excess of 100. There has been a huge increase in the quality and availability of open access/source software over the past few years. For example, private entities such as Deltares now have an open source policy regarding some flood models (NGHS). In addition, leaders in developing risk models in the public sector, such as Geoscience Australia (EQRM, TCRM, TsuDAT, AnuGA) or CAPRA (ERN-Flood, Hurricane, CRISIS2007 etc.), are launching and/or helping many other initiatives. As we achieve greater interoperability between modelling tools, we will also achieve a future wherein different open source and open access modelling tools will be increasingly connected and adapted towards unified multi-risk model platforms and highly customised solutions. It was seen that many software tools could be improved by enabling user-defined exposure and vulnerability. Without this function, many tools can only be used regionally and not at global or continental scale. It is becoming increasingly easy to use multiple packages for a single region and/or hazard to characterize the uncertainty in the risk, or use as checks for the sensitivities in the analysis. There is a potential for valuable synergy between existing software. A number of open source software packages could be combined to generate a multi-risk model with multiple views of a hazard. This extensive review has simply attempted to provide a platform for dialogue between all open source and open access software packages and to hopefully inspire collaboration between developers, given the great work done by all open access and open source developers.
NASA Astrophysics Data System (ADS)
Hörner, Tanja; Stein, Ruediger; Fahl, Kirsten
2016-04-01
Four well-dated sediment cores from the Eurasian continental shelf, i.e., the Kara Sea (Cores BP99/07 and BP00/07) and Laptev Sea (Cores PS51/154 and PS51/159), were selected for high-resolution reconstruction of past Arctic environmental conditions during the deglacial-Holocene time interval. These marginal seas are strongly affected by the post-glacial sea-level rise of about 120m. The major focus of our study was the reconstruction of the paleo-sea-ice distribution as sea-ice plays a key role within the modern and past climate system. For reconstruction of paleo-sea ice, the sea-ice proxy IP25 in combination with open-water phytoplankton biomarkers was used (for approach see Belt et al., 2007; Müller et al., 2009, 2011). In addition, specific sterols were determined to reconstruct changes in river run-off and biological production. The post-glacial sea-level rise is especially reflected in prominent decrease in terrigenous biomarkers. Deglacial variations in sea-ice cover sustained for thousand of years, mostly following climatic changes like the Bølling/Allerød (14.7-12.9 ka), Younger Dryas (12.9-11.6 ka) and Holocene warm phase (10-8 ka). Superimposed on a (Late) Holocene cooling trend, short-term fluctuations in sea-ice cover (on centennial scale) are distinctly documented in the distal/off-shore Core BP00/07 from the Kara Sea, less pronounced in the proximal/near-shore Core PS99/07 and in the Laptev Sea cores. Interestingly, this short-term variability in sea-ice cover correlates quite well to changes in Siberian river run-off (e.g., Stein et al. 2004), pointing to a direct linkage between precipitation (atmospheric circulation) and sea-ice formation. References Belt, S.T., Massé, G., Rowland, S.J., Poulin, M., Michel, C., LeBlanc, B., 2007. A novel chemical fossil of palaeo sea ice: IP25. Organic Geochemistry 38, 16-27. Müller, J., Masse, G., Stein, R., Belt, S.T., 2009. Variability of sea-ice conditions in the Fram Strait over the past 30,000 years. Nature Geoscience 2, 772-776. Müller, J., Wagner, A., Fahl, K., Stein, R., Prange, M., Lohmann, G., 2011. Towards quantitative sea ice reconstructions in the northern North Atlantic: A combined biomarker and numerical modelling approach. Earth and Planetary Science Letters 306, 137-148. Stein, R., Steinke, T., Dittmers, K., Fahl, K., Kraus, M., Matthiessen, J., Niessen, F., Pirrung, M., Polyakova, Ye., Achoster, F., Fqtterer, D.K., 2004. Terrigenous sediment supply and paleoenvironment of the Holocene Kara Sea. Quaternary Science Reviews, 23, 485-1511.
Reconstruction of past climate variability in SE Spain between 14 and 8 ka
NASA Astrophysics Data System (ADS)
Budsky, Alexander; Scholz, Denis; Mertz-Kraus, Regina; Christoph, Spötl; Gibert, Luis; Jochum, Klaus Peter; Andreae, Meinrat O.
2016-04-01
In comparison to the large climatic oscillations during the Pleistocene, Holocene climate only underwent minor changes. Nevertheless, cyclic climate changes also occurred during the Holocene. The Bond events, represented by the presence of cold, ice-bearing waters from the north of Iceland as far south as the latitude of Britain, occurred at a cyclicity of about 1500 a and were particularly pronounced during the Early Holocene. However, their climatic impact on the terrestrial realm was not consistent over Europe, in particular with respect to changes in precipitation. Here we present a precisely dated high-resolution flowstone record from Cueva Victoria, SE Spain, a site well suited to study the competing influence of the Atlantic and Mediterranean Sea on the southern Iberian Peninsula. We sampled several flowstones with a thickness of up to 60 cm. 230Th/U-dating has shown that these deposits mainly formed during relatively warm climate intervals of the Middle and Late Pleistocene, i.e. interglacials and interstadials (Budsky et al., 2015; Gibert et al., 2016). Here we focus on a short (11 cm) flowstone sequence from the Holocene with a high temporal resolution (centennial for stable isotopes and annual for trace elements). The flowstone grew between 14 and ca. 8 ka b2k. The decreasing trend of the δ18O and δ13C values as well as of several trace elements between 12 and 11 ka b2k reflects an increase in temperature and precipitation at the beginning of the Holocene. In particular, Sr and Mg show a trend towards low and stable values. Subsequently, from 10.5 to 8 ka b2k, the δ13C values show a high variability (-11 to -4), whereas the δ18O values are rather stable (between -6 and -7). Maxima in δ13C are interpreted as drier conditions in response to Bond events. These events possibly led to a change of the atmospheric circulation, affecting the vegetation in SE Spain, which evolved towards an open C3 vegetation at ca. 8 ka b2k concomitant with drier conditions. Budsky, A., Scholz, D., Gibert, L., Mertz-Kraus, R., 2015. 230Th/U-dating of the Cueva Victoria flowstone sequence: Preliminary results and paleoclimate implications, in: Gibert, L., Ferràndez-Canadell, C. (Eds.), Geology and Paleontology of Cueva Victoria. Mastia 11-13, Cartagena, pp. 101-109. Gibert, L., Scott, G.R., Scholz, D., Budsky, A., Ferràndez, C., Ribot, F., Martin, R.A., Lería, M., 2016. Chronology for the Cueva Victoria fossil site (SE Spain): Evidence for Early Pleistocene Afro-Iberian dispersals. Journal of Human Evolution 90, 183-197.
An empirical analysis of the corporate call decision
NASA Astrophysics Data System (ADS)
Carlson, Murray Dean
1998-12-01
In this thesis we provide insights into the behavior of financial managers of utility companies by studying their decisions to redeem callable preferred shares. In particular, we investigate whether or not an option pricing based model of the call decision, with managers who maximize shareholder value, does a better job of explaining callable preferred share prices and call decisions than do other models of the decision. In order to perform these tests, we extend an empirical technique introduced by Rust (1987) to include the use of information from preferred share prices in addition to the call decisions. The model we develop to value the option embedded in a callable preferred share differs from standard models in two ways. First, as suggested in Kraus (1983), we explicitly account for transaction costs associated with a redemption. Second, we account for state variables that are observed by the decision makers but not by the preferred shareholders. We interpret these unobservable state variables as the benefits and costs associated with a change in capital structure that can accompany a call decision. When we add this variable, our empirical model changes from one which predicts exactly when a share should be called to one which predicts the probability of a call as the function of the observable state. These two modifications of the standard model result in predictions of calls, and therefore of callable preferred share prices, that are consistent with several previously unexplained features of the data; we show that the predictive power of the model is improved in a statistical sense by adding these features to the model. The pricing and call probability functions from our model do a good job of describing call decisions and preferred share prices for several utilities. Using data from shares of the Pacific Gas and Electric Co. (PGE) we obtain reasonable estimates for the transaction costs associated with a call. Using a formal empirical test, we are able to conclude that the managers of the Pacific Gas and Electric Company clearly take into account the value of the option to delay the call when making their call decisions. Overall, the model seems to be robust to tests of its specification and does a better job of describing the data than do simpler models of the decision making process. Limitations in the data do not allow us to perform the same tests in a larger cross-section of utility companies. However, we are able to estimate transaction cost parameters for many firms and these do not seem to vary significantly from those of PGE. This evidence does not cause us to reject our hypothesis that managerial behavior is consistent with a model in which managers maximize shareholder value.
Scanning Probe Microscopy for Spin Mapping and Spin Manipulation on the Atomic Scale
NASA Astrophysics Data System (ADS)
Wiesendanger, Roland
2008-03-01
A fundamental understanding of magnetic and spin-dependent phenomena requires the determination of spin structures and spin excitations down to the atomic scale. The direct visualization of atomic-scale spin structures [1-4] has first been accomplished for magnetic metals by combining the atomic resolution capability of Scanning Tunnelling Microscopy (STM) with spin sensitivity, based on vacuum tunnelling of spin-polarized electrons [5]. The resulting technique, Spin-Polarized Scanning Tunnelling Microscopy (SP-STM), nowadays provides unprecedented insight into collinear and non-collinear spin structures at surfaces of magnetic nanostructures and has already led to the discovery of new types of magnetic order at the nanoscale [6,7]. More recently, the detection of spin-dependent exchange and correlation forces has allowed a first direct real-space observation of spin structures at surfaces of antiferromagnetic insulators [8]. This new type of scanning probe microscopy, called Magnetic Exchange Force Microscopy (MExFM), offers a powerful new tool to investigate different types of spin-spin interactions based on direct-, super-, or RKKY-type exchange down to the atomic level. By combining MExFM with high-precision measurements of damping forces, localized or confined spin excitations in magnetic systems of reduced dimensions now become experimentally accessible. Moreover, the combination of spin state read-out and spin state manipulation, based on spin-current induced switching across a vacuum gap by means of SP-STM [9], provides a fascinating novel type of approach towards ultra-high density magnetic recording without the use of magnetic stray fields. [1] R. Wiesendanger, I. V. Shvets, D. Bürgler, G. Tarrach, H.-J. Güntherodt, J. M. D. Coey, and S. Gräser, Science 255, 583 (1992) [2] S. Heinze, M. Bode, O. Pietzsch, A. Kubetzka, X. Nie, S. Blügel, and R. Wiesendanger, Science 288, 1805 (2000) [3] A. Kubetzka, P. Ferriani, M. Bode, S. Heinze, G. Bihlmayer, K. von Bergmann, O. Pietzsch, S. Blügel, and R. Wiesendanger, Phys. Rev. Lett. 94, 087204 (2005) [4] M. Bode, E. Y. Vedmedenko, K. von Bergmann, A. Kubetzka, P. Ferriani, S. Heinze, and R. Wiesendanger, Nature Materials 5, 477 (2006) [5] R. Wiesendanger, H.-J. Güntherodt, G. Güntherodt, R. J. Gambino, and R. Ruf, Phys. Rev. Lett. 65, 247 (1990) [6] K. von Bergmann, S. Heinze, M. Bode, E. Y. Vedmedenko, G. Bihlmayer, S. Blügel, and R. Wiesendanger, Phys. Rev. Lett. 96, 167203 (2006) [7] M. Bode, M. Heide, K. von Bergmann, P. Ferriani, S. Heinze, G. Bihlmayer, A. Kubetzka, O. Pietzsch, S. Blügel, and R. Wiesendanger, Nature 447, 190 (2007) [8] U. Kaiser, A. Schwarz, and R. Wiesendanger, Nature 446, 522 (2007) [9] S. Krause, L. Berbil-Bautista, G. Herzog, M. Bode, and R. Wiesendanger, Science 317, 1537 (2007)
Development and Experimental Study of Phantoms for Mapping Skin Chromophores
NASA Astrophysics Data System (ADS)
Silapetere, A.; Spigulis, J.; Saknite, I.
2014-06-01
Skin chromophore phantoms are widely used for better understanding of the light interaction with tissue and for calibration of skin diagnostic imaging techniques. In this work, different phantoms were examined and compared in order to find biologically equivalent substances that are the most promising for this purpose. For mimicking the skin medium and layered structure, a fibrin matrix with epidermal and dermal cell inclusion was used. Synthesized bilirubin, red blood cells and nigrosin were taken as absorbers. For spectral analysis of the developed phantoms a computer-aided multispectral imaging system Nuance 2.4 (Cambridge Research & Instrumentation, Inc., USA) was used. In this study, skin phantoms were created using such substances as bilirubin, melanin, haemoglobin and nigrosin Mūsdienās multispektrālās attēlošanas iekārtas izmanto ādas parametru un fizioloģisko procesu aprakstīšanai gan pētniecības, gan diagnostikas nolūkiem. Iekārtu darbības uzlabošanai ir nepieciešams labāk saprast gaismas mijiedarbību ar audiem, kā arī veikt šo iekārtu kalibrēšanu ar ādas maketu. Redzamā un tuvā infrasarkanā optiskā diapazona spektroskopijā ir svarīgi ādas maketi, kas simulē audu slāņaino struktūru un ķīmiskās īpašības, kā arī maketi, kas ir bioloģiski līdzvērtīgi. Šajā pētījumā tika izveidots ādas makets no bioloģiskām un ķīmiski sintezētām struktūrām. Ādas maketa izveidei tika izmantota fibrīna matrica ar dermālo un epidermālo šūnu piejaukumu, lai imitētu ādas slāņaino struktūru. Fibrīna matrica tiek veidota no 0,47 ml asins plazmas, 0,4 ml fizioloģiskā šķīduma, 0,8 μl treneksāmskābes un 89,4 μl kalcija glukanāta. Izveidoto matricu ievieto šūnu inkubatorā, lai tā polimerizētos. Nākošais slānis tiek veidots ar dermālo šūnu piejaukumu (180-270 šūnas), un pēdējais fibrīna matriksa slānis tiek veidots ar epidermālo šūnu piejaukumu (270 šūnas) un šūnu augšanu veicinošu serumu (FBS). Šūnu kultivēšanai nepieciešamas vismaz divas nedēļas. Šajā slāņainajā struktūrā ir iespējams pievienot ādas hromoforu simulējošus iekļāvumus. Optiskajā diapazonā no 450-900 nm ādas hromoforas, kurām ir visizteiktākais spektrs, ir bilirubīns, melanīns un hemoglobīns. Lai simulētu ādas hromoforu spektrālās īpašības, tika izmantots sintezēts bilirubīns, eritrocītu masa un nigrozīns. Lai izpētītu šī maketa iekārtu kalibrēšanas potenciālu, tika izveidoti 76 paraugi, kur katros 24 paraugos bija pievienots viens no absorbentiem ar dažādām koncentrācijām. Pilna ādas maketa audzēšanai nepieciešamas divas nedēļas, lai ātrāk tiktu iegūti pirmie rezultāti tika veidoti maketi bez dermālo un epidermālo šūnu piejaukuma. Fibrīna matricas un ādas imitējošā maketa absorbcijas spējas ir mazas salīdzinājumā ar hromoforu absorbcijas spējām. Lai novērtētu maketu, kas paredzēti konkrētu hromoforu spektrālo īpašību imitēšanai, iespējams veikt eksperimentus ar fibrīna matricu, kuras izveidošanai ir nepieciešama viena diena. Sintezētā bilirubīna koncentrācijas tika mainītas robežās no 0,01-2,00 mg/ml, melanīna optisko īpašību simulējošās vielas nigrozīna koncentrācija tika mainīta no 1,5 - 312,8 μg/ml, eritrocītu masas koncentrācija mainījās no 0,2 - 42,4 mg/ml.Mērījumi tika veikti, izmantojot multispektrālās attēlošanas iekārtu Cri Nuance 2.4. (Cambridge Research & Instrumentation, Inc., Amerikas Savienotās Valstis). Absorbcijas spektrs tika apstrādāts, izmantojot Microsoft Office Excel 2007. Iegūtajos rezultātos ir iespējams redzēt, ka piedāvātais ādas makets spēj simulēt ādas optiskās īpašības. Izmantotie absorbenti - sintezētais bilirubīns, nigrozīns un eritrocītu masa - spēj simulēt ādas hromoforu spektrālās īpašības. Palielinot absorbentu koncentrāciju paraugā, palielinās absorbcijas spektra maksimālā intensitāte. Izveidotais ādas makets varētu būt izmantojams iekārtu kalibrēšanai, taču šis makets nav piemērots starplaboratoriju iekārtu salīdzināšanai, jo tas nav stabils laikā
NASA Astrophysics Data System (ADS)
Geiger, S.; Driesner, T.; Matthai, S.; Heinrich, C.
2002-12-01
Realistic modelling of multi-phase fluid flow, energy and component transport in magmatic-hydrothermal systems is very challenging because hydrological properties of fluids and rocks vary over many orders of magnitude and the geometric complexities of such systems. Furthermore, density dependent component transport and transient permeability variations due to P-T changes and fluid-rock interactions introduce additional difficulties. As a result, the governing equations for the hydrodynamics, energy and component transport, and thermodynamics in magmatic hydrothermal systems are highly non-linear and strongly coupled. Essential requirements of a numerical formulation for such a system are: (1) a treatment of the hydrodynamics that can accurately resolve complex geological structures and represent the highly variable fluid velocities herein, (2) a realistic thermodynamic representation of the fluid properties including the wide P-T-X range of liquid+vapour coexistence for the highly saline fluids, and (3) an accurate handling of the highly contrasting transport properties of the two fluids. We are combining higher order finite-element (FE) methods with total variation diminishing finite volume (TVDFV) methods to model the hydrodynamics and energy and component transport of magmatic hydrothermal systems. Combined FE and TVDFV methods are mass and shock preserving, yield great geometric flexibility in 2D and 3D [2]. Furthermore, efficient matrix solvers can be employed to model fluid flow in geologically realistic structures [5]. The governing equations are linearized by operator-splitting and solved sequentially using a Picard iteration scheme. We chose the system water-NaCl as a realistic proxy for natural fluids occurring in magmatic-hydrothermal systems. An in-depth evaluation of the available experimental and theoretical data led to a consistent and accurate set of formulations for the PVTXH relations that are valid from 0 to 800 C, 0 to 500 MPa, and 0 to 1 XNaCl. Dynamic viscosities are currently approximated by the approach of Palliser and McKibbin [4]. The numerical solutions of the governing equations and the equation of state are embedded in our object-oriented C++ code CSP3D4.0 [6]. Comparisons of the numerical solutions carried out with CSP for solute transport with analytical solutions and classical test cases for density dependent flow (i.e., Elder problem [1]) show very good agreement. The numerical solutions carried out with CSP and the established United States Geological Survey code HYDROTHERM [3] for multi-phase flow and energy transport also yield a very good agreement. Fluid inclusion data can be used to constrain the PTX properties of the hydrothermal fluids in numerical solutions. [1] Journal of Fluid Mechanics 27, 609-623 [2] ANU Mathematical Research Report, MRR01-023 [3] USGS Water Investigations Report 94-4045 [4] Transport in Porous Media 33, 155-171 [5] AAPG Bulletin 80, 1763-1779 [6] CSP User's Guide, Dept. of Earth Sciences ETH Zurich
NASA Astrophysics Data System (ADS)
Willmes, M.; Boel, C.; Grün, R.; Armstrong, R.; Chancerel, A.; Maureille, B.; Courtaud, P.
2012-04-01
Strontium isotope ratios (87Sr/86Sr) can be used for the reconstruction of human and animal migrations across geologically different terrains. Sr isotope ratios in rocks are a product of age and composition and thus vary between geologic units. From the eroding environment Sr is transported into the soils, plants and rivers of a region. Humans and animals incorporate Sr from their diet into their bones and teeth, where it substitutes for calcium. Tooth enamel contains Sr isotope signatures acquired during childhood and is most resistant to weathering and overprinting, while the dentine is often diagenetically altered towards the local Sr signature. For the reconstruction of human and animal migrations the tooth enamel 87Sr/86Sr ratio is compared to the Sr isotope signature in the vicinity of the burial site and the surrounding area. This study focuses on the establishment of a comprehensive reference map of bioavailable 87Sr/86Sr ratios for France. In a next step we will compare human and animal teeth from key archaeological sites to this reference map to investigate mobility. So far, we have analysed plant and soil samples from ~200 locations across France including the Aquitaine basin, the western and northern parts of the Paris basin, as well as three transects through the Pyrenees Mountains. The isotope data, geologic background information (BRGM 1:1M), field images, and detailed method descriptions are available through our online database iRhum (http://rses.anu.edu.au/research/ee). This database can also be used in forensic studies and food sciences. As an archaeological case study teeth from 16 adult and 8 juvenile individuals were investigated from an early Bell Beaker (2500-2000 BC) site at Le Tumulus des Sables, south-west France (Gironde). The teeth were analysed for Sr isotope ratios using laser ablation ICP-MS. Four teeth were also analysed using solution ICP-MS, which showed a significant offset to the laser ablation results. This requires further detailed investigation. Nevertheless, the teeth showed clear differences between enamel and diagenetically overprinted dentine, which suggests mobility. Unfortunately, the sandy sediment units in the close vicinity of Le Tumulus des Sables show large variations in their 87Sr/86Sr ratios so it is currently not possible to distinguish between migration from outside of the Médoc region from mobility within the region based solely on Sr isotope ratios. The case study illustrates the importance of detailed reference maps, which are required for any isotope studies used for the reconstruction of migrations. Other isotope data, such as O and Pb, will complement the investigation at Tumulus de Sables and may enable us to tie down the range of mobility of the humans that were buried at Le Tumulus des Sables.
Bioinspired Engineering of Exploration Systems (BEES) - its Impact on Future Missions
NASA Technical Reports Server (NTRS)
Thakoor, Sarita; Hine, Butler; Zornetzer, Steve
2004-01-01
This paper describes an overview of our "Bioinspired Engineering of Exploration Systems for Mars" ( "BEES for Mars") project. The BEES approach distills selected biologically inspired strategies utilizing motion cues/optic flow, bioinspired pattern recognition, biological visual and neural control systems, bioinspired sensing and communication techniques, and birds of prey inspired search and track algorithmic systems. Unique capabilities so enabled, provide potential solutions to future autonomous robotic space and planetary mission applications. With the first series of tests performed in September 2003, August 2004 and September 2004, we have demonstrated the BEES technologies at the El Mirage Dry Lakebed site in the Mojave Desert using Delta Wing experimental prototypes. We call these test flyers the "BEES flyer", since we are developing them as dedicated test platform for the newly developed bioinspired sensors, processors and algorithmic strategies. The Delta Wing offers a robust airframe that can sustain high G launches and offers ease of compact stowability and packaging along with scaling to small size and low ReynOld's number performance for a potential Mars deployment. Our approach to developing light weight, low power autonomous flight systems using concepts distilled from biology promises to enable new applications, of dual use to NASA and DoD needs. Small in size (0.5 -5 Kg) BEES Flyers are demonstrating capabilities for autonomous flight and sensor operability in Mars analog conditions. The BEES project team spans JPL, NASA Ames, Australian National University (ANU), Brigham Young University(BYU), DC Berkeiey, Analogic Computers Inc. and other institutions. The highlights from our recent flight demonstrations exhibiting new Mission enabling capabilities are described. Further, this paper describes two classes of potential new missions for Mars exploration: (1) the long range exploration missions, and (2) observation missions, for real time imaging of critical ephemeral phenomena, that can be enabled by use of BEES flyers. For example, such flyers can serve as a powerful black-box for critical descent and landing data and enablers for improved science missions complementing and supplementing the existing assets like landers and rovers by providing valuable exploration and quick extended low-altitude aerial coverage of the sites of interest by imaging them and distributing instruments to them. Imaging done by orbiters allows broad surface coverage at limited spatial resolution. Low altitude air-borne exploration of Mars offers a means for imaging large areas, perhaps up to several hundred kilometers, quickly and efficiently, providing a close-up birds-eye view of the planetary terrain and close-up approach to constrained difficult areas like canyons and craters. A novel approach to low-mass yet highly capable flyers is enabled by small aircraft equipped using sensors and processors and algorithms developed using BEES technology. This project is focused towards showing the direct impact of blending the best of artificial intelligence attributes and bioinspiration to create a leap beyond existing capability for our future Missions.
IPHAS and the symbiotic stars . II. New discoveries and a sample of the most common mimics
NASA Astrophysics Data System (ADS)
Corradi, R. L. M.; Valentini, M.; Munari, U.; Drew, J. E.; Rodríguez-Flores, E. R.; Viironen, K.; Greimel, R.; Santander-García, M.; Sabin, L.; Mampaso, A.; Parker, Q.; DePew, K.; Sale, S. E.; Unruh, Y. C.; Vink, J. S.; Rodríguez-Gil, P.; Barlow, M. J.; Lennon, D. J.; Groot, P. J.; Giammanco, C.; Zijlstra, A. A.; Walton, N. A.
2010-01-01
Context. Knowledge of the total population of symbiotic stars in the Galaxy is important for understanding basic aspects of stellar evolution in interacting binaries and the relevance of this class of objects in the formation of supernovae of type Ia. Aims: In a previous paper, we presented the selection criteria needed to search for symbiotic stars in IPHAS, the INT Hα survey of the Northern Galactic plane. IPHAS gives us the opportunity to make a systematic, complete search for symbiotic stars in a magnitude-limited volume. Methods: Follow-up spectroscopy at different telescopes worldwide of a sample of sixty two symbiotic star candidates is presented. Results: Seven out of nineteen S-type candidates observed spectroscopically are confirmed to be genuine symbiotic stars. The spectral type of their red giant components, as well as reddening and distance, were computed by modelling the spectra. Only one new D-type symbiotic system, out of forty-three candidates observed, was found. This was as expected (see discussion in our paper on the selection criteria). The object shows evidence for a high density outflow expanding at a speed ≥65 km s-1. Most of the other candidates are lightly reddened classical T Tauri stars and more highly reddened young stellar objects that may be either more massive young stars of HAeBe type or classical Be stars. In addition, a few notable objects have been found, such as three new Wolf-Rayet stars and two relatively high-luminosity evolved massive stars. We also found a helium-rich source, possibly a dense ejecta hiding a WR star, which is surrounded by a large ionized nebula. Conclusions: These spectroscopic data allow us to refine the selection criteria for symbiotic stars in the IPHAS survey and, more generally, to better understand the behaviour of different Hα emitters in the IPHAS and 2MASS colour-colour diagrams. Based on observations obtained at; the 2.6 m Nordic Optical Telescope operated by NOTSA; the 2.5 m INT and 4.2 m WHT telescopes of the Isaac Newton Group of Telescopes in the Spanish Observatorio del Roque de Los Muchachos of the Instituto de Astrofísica de Canarias; the 2.3 m ANU telescope at Siding Spring Observatory, Australia; the Asiago 1.82 m telescope of the INAF Astronomical Observatory of Padova, Italy; and the 2.1 m telescope at San Pedro Martir, Mexico. Some of the INT spectra incorporated into this paper were obtained as part of a CCI International Time Programme awarded to the IPHAS collaboration. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. This research has also made use of the SIMBAD database, operated at CDS, Strasbourg, France.
Assessment of lake hydromorphological status within the French territory
NASA Astrophysics Data System (ADS)
Gay, Aurore; Argillier, Christine; Reynaud, Nathalie; Nicolas, Delphine; Baudoin, Jean-Marc
2017-04-01
In France, in accordance with the expectations of the European Water Framework Directive, the biological and physico-chemical status of lakes have been assessed thanks to the use of different indicators and threshold values (Argillier et al., 2013; Roubeix et al., 2016). However, the hydromorphological conditions have not been included in the final evaluation of the lakes ecological status yet, due to i) a lack of indicators to evaluate these conditions, ii) a lack of knowledge on the combined impact of hydromorphological changes on the biota, and iii) the difficulties in defining reference conditions for the hydromorphology of lakes. Recently, the LAKe HYdromorphological Conditions tool (LAKHYC tool, Gay et al., in prep) has been developed to overcome this lack and assess the hydromorphological conditions of lakes in Europe. The tool is successfully applied on the 201 French lakes for which accurate data are available, and which represents 42% of the total number of lakes in France with an area greater than 50ha. The first results indicate that the obtained LAKHYC values cover the entire range of possible values (between 0 and 1). The values are then grouped into 5 classes according to quintile thresholds to highlight lakes presenting a very bad/very high hydromorphological status. No sign of particular geographical distribution patterns is found. This first application of the LAKHYC tool represents an important step in the final evaluation of the ecological status of French lakes considering the biological, the physico-chemical and the hydromorphological compartments altogether. It will certainly help stakeholders to define priority lakes for financial support to implement conservation or restoration practices. As perspectives to this work, the forthcoming detailed level fluctuations data will ensure a finer and more robust estimation of the lakes hydromorphological quality. Moreover, further investigations on the link between hydromorphological degradation and the biota will allow to improve ecological assessment and to concentrate restoration priorities. Finally, we strongly encourage EU members to use the LAKHYC tool to evaluate their lake hydromorphological conditions in order to improve the LAKHYC tool and to allow for a comparison of the conditions of the European lakes. Argillier C., Caussé S., Gevrey M., Pédron S., De Bortoli J., Brucet S., Emmrich M., Jeppesen E., Lauridsen T., Mehner T., Olin M., Rask M., Volta P., Winfield I. J., Kelly F., Krause T., Palm A., Holmgren K. (2013) Development of a fish-based index to assess the eutrophication status of European lakes. Hydrobiologia 704(1):193-211 Gay A., Argillier A., Baudoin J.M., Reynaud N., Nicolas D. (in prep) Development of a methodological framework for the evaluation of lake hydromorphological conditions (LAKHYC) Roubeix V., Danis P.-A., Feret T., Baudoin J.-M. (2016). Identification of ecological thresholds from variations in phytoplankton communities among lakes: contribution to the definition of environmental standards. Environmental Monitoring and Assessment 188 (4) 188 - 246
ESA Parabolic Flight, Drop Tower and Centrifuge Opportunities for University Students
NASA Astrophysics Data System (ADS)
Callens, Natacha; Ventura-Traveset, Javier; Zornoza Garcia-Andrade, Eduardo; Gomez-Calero, Carlos; van Loon, Jack J. W. A.; Pletser, Vladimir; Kufner, Ewald; Krause, Jutta; Lindner, Robert; Gai, Frederic; Eigenbrod, Christian
The European Space Agency (ESA) Education Office was established in 1998 with the purpose of motivating young people to study science, engineering and technology subjects and to ensure a qualified workforce for ESA and the European space sector in the future. To this end the ESA Education Office is supporting several hands-on activities including small student satellites and student experiments on sounding rockets, high altitude balloons as well as microgravity and hypergravity platforms. This paper is intended to introduce three new ESA Education Office hands-on activities called "Fly Your Thesis!", "Drop Your Thesis!" and "Spin Your Thesis!". These activities give re-spectively access to aircraft parabolic flight, drop tower and centrifuge campaigns to European students. These educational programmes offer university students the unique opportunity to design, build, and eventually perform, in microgravity or hypergravity, a scientific or techno-logical experiment which is linked to their syllabus. During the "Fly Your Thesis!" campaigns, the students accompany their experiments onboard the A300 Zero-G aircraft, operated by the company Novespace, based in Bordeaux, France, for a series of three flights of 30 parabolas each, with each parabola providing about 20s of microgravity [1]. "Drop Your Thesis!" campaigns are held in the ZARM Drop Tower, in Bremen, Germany. The installation delivers 4.74s of microgravity in dropping mode and 9.3s in the catapulting mode [2]. Research topics such as fluid physics, fundamental physics, combustion, biology, material sciences, heat transfer, astrophysics, chemistry or biochemistry can greatly benefit from using microgravity platforms. "Spin Your Thesis!" campaigns take place in the Large Diameter Centrifuge (LDC) facility, at ESTEC, Noordwijk, in the Netherlands. This facility offers an acceleration from 1 to 20 times Earth's gravity [3]. The use of hypergravity allows completing the scientific picture of how gravity has an impact on a system over the whole acceleration spectrum, but can address as well specifically problems which require these high g-levels. A wide range of hypergravity exper-iments can be performed in the LDC facility, including biological, biochemical, microbiological, opto-physical, physical, material and fluid sciences, geology or plasma physics. ESA Education Office financially supports the cost of the campaigns, part of the hardware development, as well as necessary travel and accommodation of the student selected teams. An ELGRA (European Low Gravity Research Association) mentor, i.e. a scientist specialized in gravity-related research, support each student team throughout these education programmes. [1] Pletser V., Gharib T., Gai F., Mora C., Rosier P. "The 50 parabolic flight campaigns of the European Space Agency to conduct short duration microgravity research experimentation", Paper IAC-09-A2.5.1, 60th International Astronautical federation Congress, Daejeon, Korea, October 2009. [2] von Kampen P., Kaczmarczik U., Rath H.J. The new Drop Tower catapult system", Acta Astronautica, 59, 1-5, 278-283, 2006. [3] van Loon J. W. A. , Krause J., Cunha H., Goncalves J., Almeida H., Schiller P. "The Large Diameter Centrifuge, LDC, for life and physical sciences and technology", Proc. of the 'Life in Space for Life on Earth Symposium', Angers, France, 22-27 June 2008. (ESA SP-663, December 2008)
Mauz, Elvira; Hoffmann, Robert; Houben, Robin; Krause, Laura; Kamtsiuris, Panagiotis; Gößwald, Antje
2018-03-05
The implementation of an Internet option in an existing public health interview survey using a mixed-mode design is attractive because of lower costs and faster data availability. Additionally, mixed-mode surveys can increase response rates and improve sample composition. However, mixed-mode designs can increase the risk of measurement error (mode effects). This study aimed to determine whether the prevalence rates or mean values of self- and parent-reported health indicators for children and adolescents aged 0-17 years differ between self-administered paper-based questionnaires (SAQ-paper) and self-administered Web-based questionnaires (SAQ-Web), as well as between a single-mode control group and different mixed-mode groups. Data were collected for a methodological pilot of the third wave of the "German Health Interview and Examination Survey for Children and Adolescents". Questionnaires were completed by parents or adolescents. A population-based sample of 11,140 children and adolescents aged 0-17 years was randomly allocated to 4 survey designs-a single-mode control group with paper-and-pencil questionnaires only (n=970 parents, n=343 adolescents)-and 3 mixed-mode designs, all of which offered Web-based questionnaire options. In the concurrent mixed-mode design, both questionnaires were offered at the same time (n=946 parents, n=290 adolescents); in the sequential mixed-mode design, the SAQ-Web was sent first, followed by the paper questionnaire along with a reminder (n=854 parents, n=269 adolescents); and in the preselect mixed-mode design, both options were offered and the respondents were asked to request the desired type of questionnaire (n=698 parents, n=292 adolescents). In total, 3468 questionnaires of parents of children aged 0-17 years (SAQ-Web: n=708; SAQ-paper: n=2760) and 1194 questionnaires of adolescents aged 11-17 years (SAQ-Web: n=299; SAQ-paper: n=895) were analyzed. Sociodemographic characteristics and a broad range of health indicators for children and adolescents were compared by survey design and data collection mode by calculating predictive margins from regression models. There were no statistically significant differences in sociodemographic characteristics or health indicators between the single-mode control group and any of the mixed-mode survey designs. Differences in sociodemographic characteristics between SAQ-Web and SAQ-paper were found. Web respondents were more likely to be male, have higher levels of education, and higher household income compared with paper respondents. After adjusting for sociodemographic characteristics, only one of the 38 analyzed health indicators showed different prevalence rates between the data collection modes, with a higher prevalence rate for lifetime alcohol consumption among the online-responding adolescents (P<.001). These results suggest that mode bias is limited in health interview surveys for children and adolescents using a mixed-mode design with Web-based and paper questionnaires. ©Elvira Mauz, Robert Hoffmann, Robin Houben, Laura Krause, Panagiotis Kamtsiuris, Antje Gößwald. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 05.03.2018.
NASA Astrophysics Data System (ADS)
Treude, Tina; Krause, Stefan; Bertics, Victoria; Steinle, Lea; Niemann, Helge; Liebetrau, Volker; Feseker, Tomas; Burwicz, Ewa; Krastel, Sebastian; Berndt, Christian
2015-04-01
In 2008, a large area with several hundred methane plumes was discovered along the West Spitsbergen continental margin at water depths between 150 and 400 m (Westbrook et al. 2009). Many of the observed plumes were located at the boundary of gas hydrate stability (~400 m water depth). It was speculated that the methane escape at this depth was correlated with gas hydrate destabilization caused by recent increases in water temperatures recorded in this region. In a later study, geochemical analyses of authigenic carbonates and modeling of heat flow data combined with seasonal changes in water temperature demonstrated that the methane seeps were active already prior to industrial warming but that the gas hydrate system nevertheless reacts very sensitive to even seasonal temperature changes (Berndt et al. 2014). Here, we report about a methane seep site at the gas hydrate stability boundary (394 m water depth) that features unusual geochemical profiles indicative for non-steady state conditions. Sediment was recovered with a gravity corer (core length 210 cm) and samples were analyzed to study porewater geochemistry, methane concentration, authigenic carbonates, and microbial activity. Porewater profiles revealed two zones of sulfate-methane transition at 50 and 200 cm sediment depth. The twin zones were confirmed by a double peaking in sulfide, total alkalinity, anaerobic oxidation of methane, and sulfate reduction. d18O values sharply increased from around -2.8 ‰ between 0 and 126 cm to -1.2 ‰ below 126 cm sediment depth. While U/Th isotope measurements of authigenic seep carbonates that were collected from different depths of the core illustrated that methane seepage must be occurring at this site since at least 3000 years, the biogeochemical profiles suggest that methane flux must have been altered recently. By applying a multi-phase reaction-transport model using known initial parameters from the study site (e.g. water depth, temperature profile, salinity, and sediment surface concentrations of CH4, SO4, DIC, and POC) were able to show that the observed twin sulfate-methane transition zones are an ephemeral phenomenon occurring during increase of methane production in the sediment, which can be introduced by, e.g., gas hydrate dissociation. References Berndt, C., T. Feseker, T. Treude, S. Krastel, V. Liebetrau, H. Niemann, V. J. Bertics, I. Dumke, K. Dunnbier, B. Ferre, C. Graves, F. Gross, K. Hissmann, V. Huhnerbach, S. Krause, K. Lieser, J. Schauer and L. Steinle (2014). "Temporal constraints on hydrate-controlled methane seepage off svalbard." Science 343: 284-287. Westbrook, G. K., K. E. Thatcher, E. J. Rohling, A. M. Piotrowski, H. Pälike, A. H. Osborne, E. G. Nisbet, T. A. Minshull, M. Lanoiselle, R. H. James, V. Hühnerbach, D. Green, R. E. Fisher, A. J. Crocker, A. Chabert, C. Bolton, A. Beszczynska-Möller, C. Berndt and A. Aquilina (2009). "Escape of methane gas from the seabed along the West Spitsbergen continental margin." Geophys. Res. Let. 36: doi:10.1029/2009GL039191.
Improving Short Wave Breaking Behavior In Surfbeat Models
NASA Astrophysics Data System (ADS)
Roelvink, J.; Daly, C.; Vandongeren, A. R.; van Thiel de Vries, J.; McCall, R.
2009-12-01
In present surfzone modeling three approaches are widely applied: short-wave resolving models, ‘surfbeat’ models, which resolve wave energy modulations on the time-scale of wave groups and their associated infragravity waves, and wave averaged models. In all three approaches, wave breaking is a process that is highly schematized and governed by several empirical coefficients. In this presentation we will focus on the breaking process in ‘surfbeat’ models, such as XBeach (Roelvink et al, 2009). These models need to describe the short wave dissipation by breaking as a function of the slowly-varying short wave energy or wave height. The model usually applied is that by Roelvink (1993), which combines a probability that waves are breaking as function of wave heigth over water depth ratio H/h with a bore-type dissipation formulation similar to that by Battjes and Janssen (1978). A drawback of such a formulation is that there is no ‘memory’ in the breaking process, and the amount of breaking instantly varies with the water depth (though the wave height itself does have a memory). For cases with bichromatic waves, or for long-period swell, this does not reflect reality enough: waves that start breaking do not instantly stop breaking once the water depth increases, but continue until some lower threshold is reached. This concept was captured in Dally’s (1992) wave-by-wave approach, where individual waves are tracked in a probabilistic setting. We have now implemented a similar formulation in XBeach, where the property that waves are breaking is tracked; it is switched on when H/h exceeds a first criterion; this property is propagated using an advection equation and when H/h gets below a second criterion breaking is switched off. This formulation can do two things the previous one can’t: maintain groupiness inside the surf zone and have a maximum of wave breaking in the trough after a steep bar, as was observed for instance in Arcilla et al’s (1994) test 1C. Obviously this has important consequences for the forcing of both long waves and mean currents. In our presentation we will show results of comparisons of both formulations. References. Arcilla, A.S., Roelvink, J.A., O'Connor, B.A. Reniers, A., and Jimenez. J.A. The Delta Flume '93 Experiment. Coastal Dynamics '94. Arcilla, Stive and Kraus (eds), ASCE, New York, pp. 488-502. Battjes, J.A. and J.P.F.M. Janssen, (1978), Energy loss and set-up due to breaking in random waves, Proc. 16th Int. Coastal Eng. Conf., Hamburg, vol. 1: 569-587. Dally, W.R. (1992) Random breaking waves: Field verification of a wave-by-wave algorithm for engineering application. Coastal Engineering, Volume 16, Issue 4, March 1992, Pages 369-397. Roelvink, Dano, Ad Reniers, Ap van Dongeren, Jaap van Thiel de Vries, Robert McCall, Jamie Lescinski. Modelling storm impacts on beaches, dunes and barrier islands, Coast. Eng. (2009), doi:10.1016/j.coastaleng.2009.08.006 Roelvink, J.A. Dissipation in random wave groups incident on a beach. Coastal Eng., 19 (1993) pp. 127-150.
Russell, Dianne J; Sprung, Jennifer; McCauley, Dayle; Kraus de Camargo, Olaf; Buchanan, Francine; Gulko, Roman; Martens, Rachel; Gorter, Jan Willem
2016-11-11
Efforts to involve parents and families in all aspects of research, from initiating the question through to dissemination and knowledge exchange, are increasing. While social media as a method for health communication has shown numerous benefits, including increasing accessibility, interactions with others, and access to health care information, little work has been published on the use of social media to enhance research partnerships. Our objective was to describe the development and evaluation of a Web-based research advisory community, hosted on Facebook and connecting a diverse group of parents of special needs children with researchers at CanChild Centre for Childhood Disability Research. The goal of this community is to work together and exchange knowledge in order to improve research and the lives of children and their families. The Web-based Parents Participating in Research (PPR) advisory community was a secret Facebook group launched in June 2014 and run by 2 parent moderators who worked in consultation with CanChild. We evaluated its success using Facebook statistics of engagement and activity (eg, number of posts, number of comments) between June 2014 and April 2015, and a Web-based survey of members. The PPR community had 96 participants (2 parent moderators, 13 researchers, and 81 family members) as of April 1, 2015. Over 9 months, 432 original posts were made: 155 (35.9%) by moderators, 197 (45.6%) by parents, and 80 (18.5%) by researchers. Posts had a median of 3 likes (range 0-24) and 4 comments (range 0-113). Members, rather than moderators, generated 64% (277/432) of posts. The survey had a 51% response rate (49/96 members), with 40 (82%) being parent members and 9 (18%) being researchers. The initial purpose of the group was to be an advisory to CanChild, and 76% (28/37) of parents and all the researchers (9/9) identified having an impact on childhood disability research as their reason for participating. A total of 58% (23/40) of parents and 56% (5/9) of researchers indicated they felt safe to share sensitive or personal information. While researchers shared evidence-based resources and consulted with families to get guidance on specific issues, there was an unexpected benefit of gaining an understanding of what issues were important to families in their daily lives. Parents felt a sense of belonging to this community where they could share their stories but also wanted more researcher participation and clarity on the purpose of the group. The PPR community grew from inception to an established community with active engagement and knowledge exchange. Both parents and researchers described valuable experiences. Researchers should consider social media as a means of engaging families in all phases of research to ensure that research and its outcomes are meaningful to those who need it most. ©Dianne J Russell, Jennifer Sprung, Dayle McCauley, Olaf Kraus de Camargo, Francine Buchanan, Roman Gulko, Rachel Martens, Jan Willem Gorter. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 11.11.2016.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Dean N.
2011-04-02
This report summarizes work carried out by the Earth System Grid Center for Enabling Technologies (ESG-CET) from October 1, 2010 through March 31, 2011. It discusses ESG-CET highlights for the reporting period, overall progress, period goals, and collaborations, and lists papers and presentations. To learn more about our project and to find previous reports, please visit the ESG-CET Web sites: http://esg-pcmdi.llnl.gov/ and/or https://wiki.ucar.edu/display/esgcet/Home. This report will be forwarded to managers in the Department of Energy (DOE) Scientific Discovery through Advanced Computing (SciDAC) program and the Office of Biological and Environmental Research (OBER), as well as national and international collaborators andmore » stakeholders (e.g., those involved in the Coupled Model Intercomparison Project, phase 5 (CMIP5) for the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5); the Community Earth System Model (CESM); the Climate Science Computational End Station (CCES); SciDAC II: A Scalable and Extensible Earth System Model for Climate Change Science; the North American Regional Climate Change Assessment Program (NARCCAP); the Atmospheric Radiation Measurement (ARM) program; the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA)), and also to researchers working on a variety of other climate model and observation evaluation activities. The ESG-CET executive committee consists of Dean N. Williams, Lawrence Livermore National Laboratory (LLNL); Ian Foster, Argonne National Laboratory (ANL); and Don Middleton, National Center for Atmospheric Research (NCAR). The ESG-CET team is a group of researchers and scientists with diverse domain knowledge, whose home institutions include eight laboratories and two universities: ANL, Los Alamos National Laboratory (LANL), Lawrence Berkeley National Laboratory (LBNL), LLNL, NASA/Jet Propulsion Laboratory (JPL), NCAR, Oak Ridge National Laboratory (ORNL), Pacific Marine Environmental Laboratory (PMEL)/NOAA, Rensselaer Polytechnic Institute (RPI), and University of Southern California, Information Sciences Institute (USC/ISI). All ESG-CET work is accomplished under DOE open-source guidelines and in close collaboration with the project's stakeholders, domain researchers, and scientists. Through the ESG project, the ESG-CET team has developed and delivered a production environment for climate data from multiple climate model sources (e.g., CMIP (IPCC), CESM, ocean model data (e.g., Parallel Ocean Program), observation data (e.g., Atmospheric Infrared Sounder, Microwave Limb Sounder), and analysis and visualization tools) that serves a worldwide climate research community. Data holdings are distributed across multiple sites including LANL, LBNL, LLNL, NCAR, and ORNL as well as unfunded partners sites such as the Australian National University (ANU) National Computational Infrastructure (NCI), the British Atmospheric Data Center (BADC), the Geophysical Fluid Dynamics Laboratory/NOAA, the Max Planck Institute for Meteorology (MPI-M), the German Climate Computing Centre (DKRZ), and NASA/JPL. As we transition from development activities to production and operations, the ESG-CET team is tasked with making data available to all users who want to understand it, process it, extract value from it, visualize it, and/or communicate it to others. This ongoing effort is extremely large and complex, but it will be incredibly valuable for building 'science gateways' to critical climate resources (such as CESM, CMIP5, ARM, NARCCAP, Atmospheric Infrared Sounder (AIRS), etc.) for processing the next IPCC assessment report. Continued ESG progress will result in a production-scale system that will empower scientists to attempt new and exciting data exchanges, which could ultimately lead to breakthrough climate science discoveries.« less
Glacial isostatic adjustment using GNSS permanent stations and GIA modelling tools
NASA Astrophysics Data System (ADS)
Kollo, Karin; Spada, Giorgio; Vermeer, Martin
2013-04-01
Glacial Isostatic Adjustment (GIA) affects the Earth's mantle in areas which were once ice covered and the process is still ongoing. In this contribution we focus on GIA processes in Fennoscandian and North American uplift regions. In this contribution we use horizontal and vertical uplift rates from Global Navigation Satellite System (GNSS) permanent stations. For Fennoscandia the BIFROST dataset (Lidberg, 2010) and North America the dataset from Sella, 2007 were used respectively. We perform GIA modelling with the SELEN program (Spada and Stocchi, 2007) and we vary ice model parameters in space in order to find ice model which suits best with uplift values obtained from GNSS time series analysis. In the GIA modelling, the ice models ICE-5G (Peltier, 2004) and the ice model denoted as ANU05 ((Fleming and Lambeck, 2004) and references therein) were used. As reference, the velocity field from GNSS permanent station time series was used for both target areas. Firstly the sensitivity to the harmonic degree was tested in order to reduce the computation time. In the test, nominal viscosity values and pre-defined lithosphere thicknesses models were used, varying maximum harmonic degree values. Main criteria for choosing the suitable harmonic degree was chi-square fit - if the error measure does not differ more than 10%, then one might use as well lower harmonic degree value. From this test, maximum harmonic degree of 72 was chosen to perform calculations, as the larger value did not significantly modify the results obtained, as well the computational time for observations was kept reasonable. Secondly the GIA computations were performed to find the model, which could fit with highest probability to the GNSS-based velocity field in the target areas. In order to find best fitting Earth viscosity parameters, different viscosity profiles for the Earth models were tested and their impact on horizontal and vertical velocity rates from GIA modelling was studied. For every tested model the chi-square misfit for horizontal, vertical and three-dimensional velocity rates from the reference model was found (Milne, 2001). Finally, the best fitting models from GIA modelling were compared with rates obtained from GNSS data. Keywords: Fennoscandia, North America, land uplift, glacial isostatic adjustment, visco-elastic modelling, BIFROST. References Lidberg, M., Johannson, J., Scherneck, H.-G. and Milne, G. (2010). Recent results based on continuous GPS observations of the GIA process in Fennoscandia from BIFROST. Journal of Geodynamics, 50. pp. 8-18. Sella, G. F., Stein, S., Dixon, T. H., Craymer, M., James, T. S., Mazotti, S. and Dokka, R. K. (2007). Observations of glacial isostatic adjustment in "stable" North America with GPS. Geophysical Research Letters, 34, L02306. Spada, G., Stocchi, P. (2007). SELEN: A Fortran 90 program for solving the "sea-level equation". Computers & Geosciences, 33:538-562, 2007. Peltier, W. R. (2004). Global glacial isostasy and the surface of the ice-age Earth: The Ice-5G (VM2) model and GRACE. Annu. Rev. Earth Planet. Sci., 32:111-149, 2004. Fleming, K. and Lambeck, K. (2004). Constraints on the Greenland Ice Sheet since the Last Glacial Maximum from sea-level observations and glacial-rebound models. Quaternary Science Reviews 23 (2004), pp. 1053-1077. Milne, G. A. and Davis, J. L. and Mitrovica, J. X. and Scherneck, H.-G. and Johansson, J. M. and Vermeer, M. and Koivula, H. (2001). Space-geodetic constraints on glacial isostatic adjustment in Fennoscandia. Science 291 (2001), pp. 2381-2385.
The GEOSCOPE Program: state of the art in 2007
NASA Astrophysics Data System (ADS)
Roult, G.; Stutzmann, E.; Maggi, A.
2007-05-01
The GEOSCOPE program was launched in 1982 by the National Institute of Sciences of Universe (INSU), a department of the French National Center of Scientific Research (CNRS), following the initiative of the Institute of Physics of the Earth of Paris (IPGP). The purpose was the installation of about 25 stations well distributed worldwide (in particular in the southern hemisphere), in the standard configuration defined by the FDSN (very broad-band 24 bit, continuous recording at 20sps). At present, the GEOSCOPE program is operating 28 digital 3-component very- broadband stations. In terms of site locations, the aim of the GEOSCOPE program is almost fulfilled. Our purpose is to maintain the stations at original sites (Indian Ocean, Africa) and to fill some geographical gaps at high latitudes in the southern and northern hemisphere. In particular, at high latitudes in Russia, we plan to install a new station VOR (Vorkuta) and to move the station SEY (Seimchan) to a new location in northern Kamchatka. We are also working on improving data quality and transmission. Historically, GEOSCOPE did not operate real- time data. Continuous data from most of stations arrive with significant delays and records from large events are teletransmitted from some stations (by phone RTC line or through internet) and are made available within one day. To improve this situation, we are replacing the old Streckeisen digitizers with new Quanterra data loggers, essentially Q330-HR ones. Presently data from 13 stations are made available at the IPGP Geoscope Data Center in near real-time, with a delay depending on the station: 1- ATD (Arta, Djibouti), a joint CTBTO/CERD/G station 2- CAN (Canberra, Australia), a joint ANU/G station 3- DZM (Dzumac, New Caledonia, a joint DASE/CTBTO/G station 4- ECH (Echery, France) 5- FDF (Fort de France, French West Indies) 6- KIP (Kipapa, Hawai), a joint IRIS/USGS/G station 7- PAF (Port aux Français, Kerguelen Island) 8- RER (Riviere de l'Est , La Reunion) 9- SSB (Saint Sauveur-Badole, France) 10- SPB (Sao Paulo, Brazil) 11- TAM (Tamanrasset, Algeria) 12- TAOE Marquesas Islands, a joint DASE/G station 13- TRIS Tristan Da Cunha, a joint IRIS/USGS/G station Our challenge is to link the maximum number of stations to our Data Center for getting data in real time. To reach this objective in a few years, we plan to upgrade more than 2 stations every year, our priority in 2007 is the upgrade of stations PEL and COYC in Chile. For the last ten years we have been progressively installing en environmental sensors (microbaromètres, thermometers), transforming all our stations in multiparameter observatories. We also are participating to the national efforts for the creation of a Tsunami Warning Center at La Réunion Island in the frame of the CNATOI project (Centre National d'Alerte aux Tsunamis dans l'Océan Indien). That project includes the installation of two new stations in 2007, one at Rodrigues Island (Mauritius) and one at Fort- Dauphin (NAM station, Madagascar). Daily automatic procedures allow to compute the noise level plots of each component, for each station in near real-time, in order to detect any anomalous behaviour of the station and to follow the station status.
Greater carbon stocks and faster turnover rates with increasing agricultural productivity
NASA Astrophysics Data System (ADS)
Sanderman, J.; Fallon, S.; Baisden, T. W.
2013-12-01
H.H. Janzen (2006) eloquently argued that from an agricultural perspective there is a tradeoff between storing carbon as soil organic matter (SOM) and the soil nutrient and energy benefit provided during SOM mineralization. Here we report on results from the Permanent Rotation Trial at the Waite Agricultural Institute, South Australia, indicating that shifting to an agricultural management strategy which returns more carbon to the soil, not only leads to greater carbon stocks but also increases the rate of carbon cycling through the soil. The Permanent Rotation Trial was established on a red Chromosol in 1925 with upgrades made to several treatments in 1948. Decadal soil samples were collected starting in 1963 at two depths, 0-10 and 10-22.5 cm, by compositing 20 soil cores taken along the length of each plot. We have chosen to analyze five trials representing a gradient in productivity: permanent pasture (Pa), wheat-pasture rotation (2W4Pa), continuous wheat (WW), wheat-oats-fallow rotation (WOF) and wheat-fallow (WF). For each of the soil samples (40 in total), the radiocarbon activity in the bulk soil as well as size-fractionated samples was measured by accelerator mass spectrometry at ANU's Radiocarbon Dating Laboratory (Fallon et al. 2010). After nearly 70 years under each rotation, SOC stocks increased linearly with productivity data across the trials from 24 to 58 tC ha-1. Importantly, these differences were due to greater losses over time in the low productivity trials rather than gains in SOC in any of the trials. Uptake of the bomb-spike in atmospheric 14C into the soil was greatest in the trials with the greatest productivity. The coarse size fraction always had greater Δ14C values than the bulk soil samples. Several different multi-pool steady state and non-steady state models were used to interpret the Δ14C data in terms of SOC turnover rates. Regardless of model choice, either the decay rates of all pools needed to increase or the allocation of C to more actively cycling pools needed to increase in order to fit the model to the measured Δ14C data as productivity of the trial increased. In model formulations with a non-cycling passive pool (i.e. Rothamsted Carbon Model, Jenkinson 1990), the best fit solution for the 14C age of the passive pool decreased from > 2000 years in the WF trial to < 100 years in the Pa trial. The modeling analysis suggests that decay constants are not constant and that there are important feedbacks between C input rate and the turnover rate of SOC. References: Fallon S et al. (2010) The next chapter in radiocarbon dating at the Australian National University: Status report on the single stage AMS. Nuclear Instruments and Methods in Physics Research: Section B, 268: 298-901. Grace PR et al. (1995) Trends in wheat yields and soil organic carbon in the Permanent Rotation Trial at the Waite Agricultural Research Institute, South Australia. Australian Journal of Experimental Agriculture 35: 857-864. Janzen HH (2006) The soil carbon dilemma: Shall we hoard it or use it? Soil Biology and Biochemistry 38:419-424. Jenkinson DS (1990) The turnover of organic carbon and nitrogen in soil. Philosophical transactions of the Royal Society, Series B 329: 361-368
NASA Astrophysics Data System (ADS)
Budsky, Alexander; Scholz, Denis; Mertz-Kraus, Regina; Spötl, Christoph; Gibert, Luis; Jochum, Klaus Peter
2017-04-01
Here we present three flowstone records from Cueva Victoria, SE Spain, covering the period between Marine Isotope Stage (MIS) 5 and MIS 3, the Late Glacial and the Holocene. The flowstones were precisely dated by the MC-ICPMS 230Th/U-method. In addition, stable oxygen and carbon isotope ratios as well as trace element concentrations were determined at high resolution (centennial to decadal scale). Present-day climate of SE Spain is classified as semi-arid with dry summer months (<10 mm/month precipitation) and sparsely developed vegetation. A large dataset of 230Th/U ages on several flowstones from Cueva Victoria indicates preferential flowstone growth during warm phases (i.e., interglacials as well as warm interstadials), whereas flowstone growth is interrupted during glacial phases (Budsky et al., 2015). One of the drill cores shows more or less continuous flowstone growth between the Last Interglacial (MIS 5) and MIS 3 (112 - 46 ka). A flowstone from another part of the cave only records the time span from 86 to 50 ka including several growth interruptions. However, both flowstones cover the transition from MIS 4 to 3 including D/O events 17 to 13 at high resolution. Each D/O event is reflected by a remarkable decrease in both δ18O and δ13C values (both up to 3‰ ) accompanied by decreasing concentrations of Mg and Sr. In particular, longer D/O events, lasting several thousands of years (e.g., D/O 14, 19, 20 and 21), are well represented in the δ18O and δ13C records. The timing is in good agreement with the NGRIP ice core and sea-surface temperatures from the Iberian margin. δ18O values are around -3.5 ‰ and decrease to -5 to -6 ‰ during D/O events, while δ13C values are around -9 ‰ and decrease to -10 to -11 ‰ ) during D/O events. We interpret these changes as more humid conditions during D/O events, with elevated sea-surface temperatures in the North Atlantic and the Mediterranean Sea leading to increased moisture transport and precipitation on the SE Iberian Peninsula. As a consequence, vegetation density increased, which is reflected by the decrease in δ13C values and Mg and Sr concentrations and an increase in P content. In the Holocene, the flowstone grew continuously from the Bølling/Allerød to the mid-Holocene (7 ka). Stable isotopes record a trend of increasing temperatures with decreasing values towards the mid-Holocene (δ18O ≈ - 6.4 ‰ , δ13C ≈ -11 ‰ ). However, δ13C values record a significant excursion with elevated values (up to -3.8 ‰ ) during a period from 9.5 to 7.7 ka related to cold Bond-events in the North Atlantic, which is interpreted as a dry period in SE Spain. Budsky, A., Scholz, D., Gibert, L., Mertz-Kraus, R., 2015. 230Th/U-dating of the Cueva Victoria flowstone sequence: Preliminary results and paleoclimate implications, in: Gibert, L., Ferràndez-Canadell, C. (Eds.), Geology and Paleontology of Cueva Victoria. Mastia 11-13, Cartagena, pp. 101-109.
Simulation of n-qubit quantum systems. III. Quantum operations
NASA Astrophysics Data System (ADS)
Radtke, T.; Fritzsche, S.
2007-05-01
During the last decade, several quantum information protocols, such as quantum key distribution, teleportation or quantum computation, have attracted a lot of interest. Despite the recent success and research efforts in quantum information processing, however, we are just at the beginning of understanding the role of entanglement and the behavior of quantum systems in noisy environments, i.e. for nonideal implementations. Therefore, in order to facilitate the investigation of entanglement and decoherence in n-qubit quantum registers, here we present a revised version of the FEYNMAN program for working with quantum operations and their associated (Jamiołkowski) dual states. Based on the implementation of several popular decoherence models, we provide tools especially for the quantitative analysis of quantum operations. Apart from the implementation of different noise models, the current program extension may help investigate the fragility of many quantum states, one of the main obstacles in realizing quantum information protocols today. Program summaryTitle of program: Feynman Catalogue identifier: ADWE_v3_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWE_v3_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions: None Operating systems: Any system that supports MAPLE; tested under Microsoft Windows XP, SuSe Linux 10 Program language used:MAPLE 10 Typical time and memory requirements: Most commands that act upon quantum registers with five or less qubits take ⩽10 seconds of processor time (on a Pentium 4 processor with ⩾2 GHz or equivalent) and 5-20 MB of memory. Especially when working with symbolic expressions, however, the memory and time requirements critically depend on the number of qubits in the quantum registers, owing to the exponential dimension growth of the associated Hilbert space. For example, complex (symbolic) noise models (with several Kraus operators) for multi-qubit systems often result in very large symbolic expressions that dramatically slow down the evaluation of measures or other quantities. In these cases, MAPLE's assume facility sometimes helps to reduce the complexity of symbolic expressions, but often only numerical evaluation is possible. Since the complexity of the FEYNMAN commands is very different, no general scaling law for the CPU time and memory usage can be given. No. of bytes in distributed program including test data, etc.: 799 265 No. of lines in distributed program including test data, etc.: 18 589 Distribution format: tar.gz Reasons for new version: While the previous program versions were designed mainly to create and manipulate the state of quantum registers, the present extension aims to support quantum operations as the essential ingredient for studying the effects of noisy environments. Does this version supersede the previous version: Yes Nature of the physical problem: Today, entanglement is identified as the essential resource in virtually all aspects of quantum information theory. In most practical implementations of quantum information protocols, however, decoherence typically limits the lifetime of entanglement. It is therefore necessary and highly desirable to understand the evolution of entanglement in noisy environments. Method of solution: Using the computer algebra system MAPLE, we have developed a set of procedures that support the definition and manipulation of n-qubit quantum registers as well as (unitary) logic gates and (nonunitary) quantum operations that act on the quantum registers. The provided hierarchy of commands can be used interactively in order to simulate and analyze the evolution of n-qubit quantum systems in ideal and nonideal quantum circuits.
NASA Astrophysics Data System (ADS)
Skridlaite, G.; Bogdanova, S.; Taran, L.; Baginski, B.; Krzeminska, E.; Wiszniewska, J.; Whitehouse, M.
2009-04-01
Several Palaeoproterozoic terranes in the Fennoscandian lithospheric segment of the East European Craton (EEC) evolved differently prior to their final amalgamation at c. 1.8 Ga. South-westward younging of the major tectono-thermal events characterizes the Baltic -Belarus region between the Baltic and Ukrainian Shields of the EEC. While at c.1.89-1.87 Ga and 1.85-1.84 Ga rocks of some northern and eastern terranes (Estonia, Belarus and eastern Lithuania) experienced syncollisional, moderate P metamorphism, subduction-related volcanic island arc magmatism still dominated southwestern terranes in Lithuania and Poland. The available age determinations of metamorphic zircon (SIMS/NORDSIM and TIMS methods, Stockholm, SHRIMP method, RSES, ANU, Canberra) and metamorphic monazite (TIMS, Stockholm and EPMA method, Warsaw University) allow to distinguish several metamorphic events related to major orogenic processes: - 1.90-1.87 Ga amphibolite-facies H/MP metamorphism occurred along with emplacements of juvenile TTG-type granitoids in the North Estonian and Lithuanian-Belarus terranes. They are coeval with the main accretionary growth of the crust in the Svecofennian Domain in the Baltic Shield (e.g. Lahtinen et al., 2005). - 1.84-1.79 Ga high-grade metamorphism affected sedimentary and igneous rocks in almost all the terranes and is assumed to have been related to the major aggregation of the EEC (Bogdanova et al, 2006, 2008). In the metasedimentary granulites of western Lithuania, a prograde metamorphism commenced with monazite growth prior garnet at 1.84-1.83 Ga. The sediments and mafic igneous rocks in Lithuania, felsic igneous rocks in NE Poland underwent peak metamorphism and deformation at 1.81-1.79 Ga (zircon and monazite ages). The 1.83-1.79 Ga metamorphism has the same age as a metamorphic imprint and strong shearing of the crust in central Sweden (Andersson et al., 2004). The postcollisional granulite metamorphism of mafic intrusions at 1.80-1.79 Ga in Belarus indicates that the NW-SE collision can have triggered the crustal/mantle disturbance along the Fennoscandia-Sarmatia suture zone. - c. 1.7-1.6 Ga moderate PT metamorphic overprint and deformation of 1.83-1.82 Ga magmatic charnockites and c. 1.8 Ga metamorphic granulites in western Lithuania was recorded by the growth of a new garnet, zircon and monazite. The dated charnockites and metasediments contain metamorphic monazite of both 1.60-1.59 Ga and 1.7-1.65 Ga ages. These metamorphic events can reflect a distal influence of the 1.7-1.6 Ga Gothian orogeny in SW Fennoscandia (e.g. Ahall and Connelly, 2008). - 1.55-1.50 and 1.50-1.45 Ga events. In southern Lithuania, the 1.53-1.50 Ga AMCG magmatism was accompanied by high-grade metamorphism. Deformation and amphibolite facies metamorphism are marked by the 1.55-1.45 Ga 40Ar/39Ar ages of hornblende along EW-trending lineaments in central and southeastern Lithuania and Belarus. There are also indications of shearing and low grade, c. 1.50 Ga, metamorphism of metasedimentary rocks and charnockites in NW Lithuania and NE Poland. Altogether, the coeval AMCG magmatism, local high-grade and widespread low-grade metamorphism, and deformation can be manifestations of the Danopolonian orogeny, particularly prominent around the South Baltic Sea. This is a contribution to the project "The Precambrian structure of Baltica as a control of its recent environment and evolution" of the Visby Programme (the Swedish Institute) and SYNTHESYS project SE-TAF-1535. References Ahall, K.I. and Connelly, J.N., 2008. Precambrian Research, 161(3-4): 452-474. Andersson, U.B. et al., 2004, GFF 126, 16-17. Bogdanova, S. et al., 2006, Geological Society, London Memoirs, 32, pp. 599-628 Bogdanova, S. et al., 2008, Precambrian Research 160, 23-45. Lahtinen, R., et al., 2005. In: Precambrian Geology of Finland - Key to the Evolution of the Fennoscandian Shield. Elsevier, Amsterdam, 481-532
NASA Astrophysics Data System (ADS)
Bezrukovs, Vl.; Shmeld, I.; Nechaeva, M.; Trokss, J.; Bezrukovs, D.; Klapers, M.; Berzins, A.; Lesins, A.; Dugin, N.
2012-12-01
Radiotelescope RT-32 is a fully steerable 32-m parabolic antenna located at Irbene and belonging to Ventspils International Radio Astronomy Centre (VIRAC). Currently, the work on upgrading and repair of its receiving hardware and data acquisition systems is of high priority for the VIRAC. One of the main scientific objectives for the VIRAC Radioastronomical observatory is VLBI (very long baseline interferometry) observations in centimetre wavelengths in collaboration with world VLBI networks, such as European VLBI network (EVN), Low Frequency VLBI network (LFVN), and others. During the last years the room in the secondary focus of telescope was reconstructed, and several new receivers were installed. Currently, RT-32 observations are carried out in four different bands: 92 cm, 18 cm, 6 cm, and 2.5 cm. First three of them are already successfully employed in diversified VLBI experiments. The receiver on 2.5 cm band has only one linear polarized chain and is used mainly for the methanol maser single dish observations. The apparatus system of RT-32 is equipped with two independent VLBI data acquisition systems: TN-16, and DBBC in combination with MK5b. Both systems are employed in interferometric observations depending on the purpose of experiment and the enabled radiotelescopes. The current status of RT-32, the availability of its receiving and data acquisition units for VLBI observations and the previous VLBI sessions are discussed. Radioteleskops RT-32 ir Ventspils Starptautiskajam Radioastronomijas Centram (VSRC) piederoša pilnas piedziņas 32 m diametra paraboliskā antena. Pašreiz visaktuālākie VSRC veicamie darbi ir saistīti ar RT-32 uztverošās aparatūras un datu reģistrēšanas sistēmas labošanu un modernizāciju. Viens no radioastronomiskās observatorijas galvenajiem zinātniskajiem uzdevumiem ir sevišķi lielas bāzes interferometriskie (VLBI) novērojumi centimetru viļņu garumu diapazonā sadarbībā ar pasaules VLBI tīkla partneriem, tādiem kā Eiropas VLBI tīkls, Zemo frekvenču VLBI tīkls (LFVN) un citiem. Pēdējos gados rekonstruēta teleskopa sekundārajā fokusā izvietotā uztvērēju telpa un tajā uzstādīti vairāki jauni uztvērēji. Pašreiz radioteleskops ļauj veikt novērojumus četros viļņu garumu diapazonos: 92 cm, 18 cm, 6 cm un 2.5 cm. No minētajiem pirmie 3 jau tiek veiksmīgi izmantoti dažādos VLBI eksperimentos. 2.5 cm uztvērējam ir tikai viens lineārās polarizācijas kanāls, kuru izmanto galvenokārt metanola māzeru novērojumiem viena teleskopa režīmā. RT-32 aparatūru veido divas neatkarīgas VLBI datu reģistrācijas sistēmas: TN-16 un DBBC kopā ar Mark5b. Abas sistēmas izmanto interferometriskajos novērojumos atkarībā no eksperimentu mērķa un radioteleskopa iespējām. Aplūkots Irbenes RT-32 radioteleskopa pašreizējais statuss, tā VLBI novērojumiem piemērotās uztveršanas un datu reģistrācijas iekārtas, kā arī notikušajās VLBI sesijās uzkrātā pieredze.
Foreword: 18th Aps-Sccm and 24th Airapt
NASA Astrophysics Data System (ADS)
Collins, Gilbert; Moore, David S.; Yoo, Choong-Shik
2014-05-01
This second joint conference between the APS Topical Group on Shock Compression of Condensed Matter and the International Association for the Advancement of High Pressure Science and Technology (AIRAPT) demonstrates that static and dynamic compression of condensed matter continues to be a vibrant field of science and engineering. It is also by its nature an interdisciplinary field, incorporating chemistry, materials science, solid mechanics, plasma physics, and condensed matter physics, and utilizes theoretical, computational, and experimental tools. Recent years have brought about many advances in loading platforms, diagnostics, and computations that are leading to the emergence of many new avenues of research. These advances are also breathing new life into traditional topics such as equations of state, phase transformations, and chemistry at extreme conditions. The plenary lectures by Gennady Kanel, Karl Syassen, David Ceperley, Jon Eggert, Duck Young Kim, and Richard Kraus spanned the disciplines of static and dynamic high pressure physics and illustrated the breadth of the field. They also showed that interesting and important problems remain for researchers of the future to solve. The main guiding principal in the organization of this conference was to intertwine static and dynamical experimental alongside computational and theoretical studies of similar materials. To achieve this goal, we arranged the conference to include static, dynamic, and computational components in the same sessions, quite often taking presenters out of their comfort zone. The three special sessions on Deep Carbon Budget (organized by Giulia Galli and Rus Hemley), High Energy Density Materials (organized by Raymond Jeanloz and Jon Eggert), and Dynamic Response of Materials (organized by Yogendra Gupta and John Sarrao) furthered this guiding principal. We also endeavored to represent the breadth of static and dynamic high pressure science and technology, notably beyond that done at national laboratories. To this end, a significant fraction of the plenary, invited and contributed presentations showcased work done in academia, defense laboratories and industry, as well as internationally. Although travel distance and visa issues always present difficulties, the conference had strong representation from a record number of international participants, including sizable groups from Russia and China (thanks to Tony Zocher and Frank Cherne), as well as Japan, the United Kingdom, France, Canada, Germany, Israel, and Italy. It is our sincere hope that international interactions that occurred at the conference will lead to further collaborations in the future. Finally, we strived to increase student participation at the conference. Through the leadership of Scott Alexander and his committee, a new all-day student symposium was held the day before the main conference, with only student attendees and presenters, in order to acclimate the students to conference participation and help them network with their peers. In cooperation with the APS Topical Group and the AIRAPT and with additional support from DTRA and the AWE, the conference was able to provide financial assistance to a large number of students to attend the conference and present their research. This aid helped increase the number of student attendees significantly over previous conferences. Finally, the conference sponsored a networking lunch for students and representatives from a number of laboratories and other institutions, which was well attended. Seattle proved itself to be an excellent venue for the conference. The international flavor of the city provided ample dining options and numerous activity choices outside of the conference sessions. The major international airport made travel as easy as possible, as Seattle is a convenient central location for attendees from Europe and Asia. The conference was truly a team effort with critical contributions from many individuals. We deeply appreciate their contributions to the success of the conference and the publication of these proceedings. Gilbert (RIP) Collins David S Moore Choong-Shik Yoo
NASA Astrophysics Data System (ADS)
Newbury, D. E.
2006-05-01
X-ray mapping, performed with the electron probe microanalyzer (EPMA) or scanning electron microscope/energy dispersive x-ray spectrometer (SEM/EDS), is one of the most popular modes of studying chemically heterogeneous microstructures [1]. Despite the maturity of the technique, now in its 50th anniversary year [2], recent remarkable advances in instrumentation and software will provide microanalysts with an even more effective and efficient microstructural characterization tool: (1) Increased x-ray mapping speed: The silicon drift detector (SDD) [3] is a new form of the familiar silicon EDS that uses the same detection physics but with a radically different design that outperforms the classic Si-EDS in nearly every way [4]: (1) the SDD operates requires only Peltier cooling to -20 oC to - 50 oC; (2) for a given detector active area, the SDD has superior resolution; (3) the SDD achieves the same resolution but with a peaking time that is 5 to 8 times faster; and (4) maximum output count rate (OCR) ranges from about 14 kHz at optimum resolution (134 eV at MnKa for a 50 mm2 area) to 500 kHz (217 eV). This OCR performance enables rapid x-ray mapping collection in the x-ray spectrum image (XSI) mode, in which a complete EDS spectrum (2048 10eV-channels) is captured at each pixel (e.g., 10 ms dwell with 1.3 ms overhead per pixel, or 185 seconds for a 128x128 pixel map). XSI collection captures all possible spectral information within the limits imposed by the spectrometer and the primary beam dose. (2) EDS with WDS resolution: The microcalorimeter EDS measures the temperature rise when a single x-ray photon is absorbed in a metal target [5]. Demonstrated resolution is 4.5 eV at Mn Ka for a broad energy range (0.2 - 10 keV) spectrometer and 2 eV (AlKa) for a low photon energy range (0.2 - 2.0 keV) version. The low energy spectrometer is sensitive to peak shape and position changes associated with chemical bonding, opening the possibility of EDS chemical-state mapping. (3) Data mining: In the XSI mode, data is captured at the rate of 100 Mbytes per XSI database or more. Efficient software tools have been developed that enable the analyst to quickly recognize major and minor constituent features in this datacube, and even to detect rare unexpected features that occur at only one pixel in a large map [6]. Advanced image cube data reduction can be achieved with tools based on statistical methods, such as principal component analysis, that quickly establishes correlations between different elements, such as distinct phases [7]. 1. Goldstein, J., Newbury, D., Joy, D., Lyman, C., Echlin, P., Lifshin, E., Sawyer, L., and Michael, J., Scanning Electron Microscopy and X-ray Microanalysis, 3rd edition (Kluwer Academic Plenum Press, New York, 2003). 2. Cosslett, E. and P. Duncumb, Nature, 177 (1956) 1172. 3. Struder, L., Fiorini, C., Gatti, E., Hartmann, R., Holl, P., Krause, N., Lechner, P., Longoni, A., Lutz, G., Kemmer, J., Meidinger, N., Popp, M., Soltau, H., and van Zanthier, C., High resolution non dispersive x-ray spectroscopy with state of the art silicon detectors, Mikrochim. Acta, Suppl, 15 (1998) 11 4. Newbury, D. SCANNING, 27 (2005) 227. 5. Wollman, D., Irwin, K., Hilton, G., Dulcie, L., Newbury, D., and Martinis, J., J. Micros. 188 (1997) 196. 6. Newbury, D. and Bright, D., SCANNING, 27 (2005) 15. 7. Kotula, P. Keenan, M., and Michael J., Micros. Microanal. 9 (2003) 1
NASA Astrophysics Data System (ADS)
Lansdown, Katrina; Trimmer, Mark; Heppell, Kate
2010-05-01
Typically characterised by steep chemical gradients and variable redox conditions, the hyporheic zone is considered a 'hotpot' or site of enhanced biogeochemical activity in the aquatic environment. As such the importance of the hyporheic zone for the attenuation of nutrients such as nitrate in a fluvial network has long been recognised. Controls on nitrogen transformations, however, especially at depths greater than 10cm below the sediment-water interface, remain comparatively less understood. Most work aimed at quantifying denitrification in the hyporheic zone has involved laboratory incubation of recovered sediments which is likely to affect the estimate of the true in situ rate. Results of such studies are usually cited as 'potential' rates of denitrification and have undoubtedly improved the understanding of nitrogen cycling in the aquatic environment. There is, however, a need for in situ measurement to improve our knowledge of nitrogen cycling in the river bed. Here, rates of denitrification in the hyporheic zone have been measured at multiple depths, simultaneously using 'push-pull' methodology (e.g. Snodgrass and Kitanidis 1998). The 'push-pull' technique involves injection of a solution containing reactant(s) (e.g. nitrate) and a conservative tracer (e.g. chloride) into the sediment and extraction of pore water samples over time. Recovered samples are screened for the removal of reactant(s) and/or the accumulation of products(s). Temporal changes in the conservative tracer are used to correct the concentration of the reactant(s) and product(s) for dispersion and advection. The disadvantage of the 'traditional' 'push-pull' methodology is that rates of nitrate removal are measured rather than rates of denitrification. In this research, comparison of measured and 'corrected' nitrate concentrations allowed the rate of nitrate removal (or production) to be quantified. In order to determine in situ rates of denitrification we used 15N-enriched nitrate as the reactant in the 'push-pull' experiments and measured the accumulation of 29N2 and 30N2 over time. Rates of denitrification were then calculated using the isotope pairing technique (as per Nielsen 1992; Sanders and Trimmer 2006). Measurements have been made at up to 40cm depth in the river bed using a miniprobe system developed from the design of Sanders and Trimmer (2006) in order to validate the experimental approach. Previous work conducted at the study site (R. Leith, Cumbria, UK) suggested than ambient conditions would not be ideal for in situ measurement of denitrification rates using 'push-pull' methodology. Slow rates of denitrification were measured during laboratory incubations of the sandy sediment (M. Trimmer, unpublished data), and the velocity of flow in the hyporheic zone would limit the duration of the in situ measurement (Käser et al. 2009). Despite difficulties posed by the site, we have measured in situ rates of denitrification at multiple depths in the hyporheic zone simultaneously. We also report measurement of in situ rates of denitrification below the zone of surface water - ground water mixing. In future we will use the experimental technique described in this paper to quantify (i) variation in N transformation rates with depth; and (ii) spatial variation in rates of nitrate consumption/production within the river bed. Käser, DH, Binley, A, Heathwaite, AL and Krause, S (2009) Spatio-temporal variations of hyporheic flow in a riffle-pool sequence. Hydrological Processes 23: 2138 - 2149. Nielsen, LP (1992) Denitrification in sediment determined from nitrogen isotope pairing. FEMS Microbiology Ecology 86: 357 - 362. Sanders, IA and Trimmer, M (2006) In situ application of the 15NO3- isotope pairing technique to measure denitrification in sediments at the surface water-groundwater interface. Limnology and oceanography: Methods 4: 142 - 152. Snodgrass, MF and Kitanidis, PK (1998) A method to infer in situ reaction rates from push-pull experiments. Ground Water 36(4): 645 - 650.
NASA Astrophysics Data System (ADS)
Lansdown, Katrina; Heppell, Kate; Ullah, Sami; Heathwaite, A. Louise; Trimmer, Mark; Binley, Andrew; Heaton, Tim; Zhang, Hao
2010-05-01
The dynamics of groundwater and surface water mixing and associated nitrogen transformations in the hyporheic zone have been investigated within a gaining reach of a groundwater-fed river (River Leith, Cumbria, UK). The regional aquifer consists of Permo-Triassic sandstone, which is overlain by varying depths of glaciofluvial sediments (~15 to 50 cm) to form the river bed. The reach investigated (~250m long) consists of a series of riffle and pool sequences (Käser et al. 2009), with other geomorphic features such as vegetated islands and marginal bars also present. A network of 17 piezometers, each with six depth-distributed pore water samplers based on the design of Rivett et al. (2008), was installed in the river bed in June 2009. An additional 18 piezometers with a single pore water sampler were installed in the riparian zone along the study reach. Water samples were collected from the pore water samplers on three occasions during summer 2009, a period of low flow. The zone of groundwater-surface water mixing within the river bed sediments was inferred from depth profiles (0 to 100 cm) of conservative chemical species and isotopes of water with the collected samples. Sediment cores collected during piezometer installation also enabled characterisation of grain size within the hyporheic zone. A multi-component mixing model was developed to quantify the relative contributions of different water sources (surface water, groundwater and bank exfiltration) to the hyporheic zone. Depth profiles of ‘predicted' nitrate concentration were constructed using the relative contribution of each water source to the hyporheic and the nitrate concentration of the end members. This approach assumes that the mixing of different sources of water is the only factor controlling the nitrate concentration of pore water in the river bed sediments. Comparison of predicted nitrate concentrations (which assume only mixing of waters with different nitrate concentrations) with actual nitrate concentrations (measured from samples collected in the field) then allows patches of biogeochemical activity to be identified. The depth of the groundwater-surface water mixing zone was not uniform along the study reach or over the three sampling periods, varying from <10 to 50 cm in depth. The influence of factors such as the strength of groundwater upwelling, channel geomorphology, substrate composition (permeability) and river discharge on the extent of groundwater-surface mixing have been investigated. During the three field campaigns conducted, groundwater nitrate concentrations (100 cm) were higher than surface water nitrate concentrations (3.7 ± 0.4 mg N/L versus 2.0 ± 0.03 mg N/L; p < 0.001; n = 27), indicating that throughout the reach investigated groundwater will supply nitrate to the overlying water column unless nitrate attenuation occurs along the upwelling flow path. Actual (measured) pore water nitrate concentrations often differed from concentrations predicted using the mixing model, which suggests that biogeochemical transformations also affected nitrate concentrations in the hyporheic zone. The initial field data suggested that there were regions of both nitrate production and nitrate consumption in the subsurface sediments, and that these zones may extend beyond the depths commonly associated with the hyporheic zone. This research demonstrates that a multi-component mixing model can be used to identify possible hotspots of nitrate production or consumption in the bed of a groundwater-fed river. Käser, DH, Binley, A, Heathwaite, AL and Krause, S (2009) Spatio-temporal variations of hyporheic flow in a riffle-pool sequence. Hydrological Processes 23: 2138 - 2149. Rivett, MO, Ellis, PA, Greswell, RB, Ward, RS, Roche, RS, Cleverly, MG, Walker, C, Conran, D, Fitzgerald, PJ, Willcox, T and Dowle, J (2008) Cost-effective mini drive-point piezometers and multilevel samplers for monitoring the hyporheic zone. Quarterly Journal of Engineering Geology and Hydrogeology 41: 49 - 60.
Higher-spin theory and holography
NASA Astrophysics Data System (ADS)
Gaberdiel, Matthias; Vasiliev, Mikhail
2013-05-01
This special issue of Journal of Physics A: Mathematical and Theoretical reviews recent developments in higher-spin gauge theories and their applications to holographic dualities. The analysis of higher-spin theories has a very long history, but it took until the mid 1980s for the first consistent higher-spin interactions to be constructed by Bengtsson, Bengtsson and Brink [1] and Berends, Burgers and van Dam [2]. Somewhat later it was shown by Fradkin and Vasiliev [3] that consistent higher-spin gauge theories that involve gravity should necessarily be defined on a curved background. The first consistent interacting higher-spin theories were then formulated at the classical level by Vasiliev in the early 1990s [4]. These higher-spin theories involve an infinite number of massless higher-spin fields that support higher-spin gauge symmetries, and indeed, are largely characterized by this underlying gauge symmetry. The simplest examples are provided by higher-spin theories on (anti)-de Sitter spaces, and in a sense, this anticipated the AdS/CFT correspondence. Indeed, in the tensionless limit of string theory, the massive excitations of string theory become massless, and hence define higher-spin gauge fields. On the other hand, from the dual gauge theory perspective, this is the limit in which the field theory becomes free, and therefore has many conserved higher-spin currents. By the usual AdS/CFT dictionary, these are dual to the higher-spin gauge symmetries of the bulk description. Following this line of argument, Sundborg [5] and Witten [6] suggested in 2001 that a duality relating a higher-spin theory on AdSd to a weakly coupled (d - 1)-dimensional conformal field theory should exist. A concrete proposal was then made by Klebanov and Polyakov [7] who conjectured that the simplest version of a higher-spin gauge theory on AdS4 should be dual to the 3d O(N ) vector model. Recently, much support for this conjecture was obtained by Giombi and Yin [8], and in turn, this has triggered a significant amount of activity in this general area. Among other things, the constraints that are implied by the higher-spin symmetries were analysed (see the paper by Maldacena and Zhiboedov in this issue [9]), and a fairly concrete proposal for how higher-spin theories are related to string theory was made (see the paper by Chang, Minwalla, Sharma and Yin in this issue [10]). Furthermore, a lower dimensional version of the conjecture was put forward by Gaberdiel and Gopakumar [11] that was subsequently also checked in some detail. These dualities hold the promise of offering insights into the inner workings of the AdS/CFT correspondence since they are complex enough to capture the essence of the duality, while at the same time being sufficiently simple in order to allow for a detailed analysis. Moreover, the methods specifically developed in higher-spin theory may be useful for understanding a general mechanism underlying holography, both in higher-spin models and beyond (see the paper by Vasiliev in this issue [12]). Another fascinating aspect of these higher-spin theories lies in the fact that the higher-spin symmetries mix generically fields of different spin, and in particular, the spin-2 metric and higher-spin excitations are related to one another by gauge transformations. As a result, higher-spin theories require a modification of the standard framework of Riemannian geometry since the usual diffeomorphism-invariant tensors are not gauge invariant any longer. In particular, higher-spin theories may therefore open the way towards understanding fundamental concepts of space-time geometry; for example, they may well have key lessons in store for how string theory resolves space-time singularities. In this issue we have collected together a number of review papers, summarizing the aforementioned recent developments, as well as research papers indicating current directions of interest in the study of higher-spin gauge theories. We hope that it will be useful, both for beginners interested in an introduction to the subject, and for experts already working in the field. Three of the reviews deal with the holographic dualities mentioned above: the paper by Giombi and Yin [13] reviews the situation for AdS4/CFT3, while the review by Gaberdiel and Gopakumar [14] deals with the lower-dimensional AdS3/CFT2 version. In addition, the review by Jevicki, Jin and Ye [15] explains a possible way of proving the duality using collective fields. There are two reviews on the construction of black holes in higher-spin gauge theories: the review by Iazeolla and Sundell [16] reviews the situation for 4d higher-spin theories, while the review by Ammon, Gutperle, Kraus and Perlmutter [17] deals with the three-dimensional case for which much progress has been made recently. Finally, the review of Sagnotti [18] explains various general aspects of higher-spin gauge theories. The research papers deal with different aspects of current developments; some are concerned with the holographic duality, while others develop the general theory of higher-spin fields. References [1] Bengtsson A K H, Bengtsson I and Brink L 1983 Cubic interaction terms for arbitrarily extended supermultiplets Nucl. Phys. B 227 41 [2] Berends F A, Burgers G J H Van Dam H 1984 On spin three self interactions Z. Phys. C 24 247 [3] Fradkin E S Vasiliev M A 1987 On the gravitational interaction of massless higher-spin fields Phys. Lett. B 189 89 [4] Vasiliev M A 1992 More on equations of motion for interacting massless fields of all spins in 3+1 dimensions Phys. Lett. B 285 225 [5] Sundborg B 2001 Stringy gravity, interacting tensionless strings and massless higher spins Nucl. Phys. Proc. Suppl. 102 113 (arXiv:hep-th/0103247) [6] Witten E 2001 Spacetime reconstruction Talk at the John Schwarz 60th Birthday Symp. (http://theory.caltech.edu/jhs60/witten/1.html) [7] Klebanov I R Polyakov A M 2002 AdS dual of the critical O (N ) vector model Phys. Lett. B 550 213 (arXiv:hep-th/0210114) [8] Giombi S Yin X 2010 Higher spin gauge theory and holography: the three-point functions J. High Energy Phys. JHEP09(2010)115 (arXiv:0912.3462 [hep-th]) [9] Maldacena J Zhiboedov A 2013 Constraining conformal field theories with a higher spin symmetry J. Phys. A: Math. Theor. 46 214011 (arXiv:1204.3882 [hep-th]) [10] Chang C-M, Minwalla A, Sharma T Yin X 2013 ABJ triality: from higher spin fields to strings J. Phys. A: Math. Theor. 46 214009 (arXiv:1207.4485 [hep-th]) [11] Gaberdiel M R Gopakumar R 2011 An AdS3 dual for minimal model CFTs Phys. Rev. D 83 066007 (arXiv:1011.2986 [hep-th]) [12] Vasiliev M A 2013 Holography, unfolding and higher-spin theory J. Phys. A: Math. Theor. 46 214013 (arXiv:1203.5554 [hep-th]) [13] Giombi S Yin X 2013 The higher spin/vector model duality J. Phys. A: Math. Theor. 46 214003 (arXiv:1208.4036 [hep-th]) [14] Gaberdiel M R Gopakumar R 2013 Minimal model holography J. Phys. A: Math. Theor. 46 214002 (arXiv:1207.6697 [hep-th]) [15] Jevicki A, Jin K Ye Q 2013 Perturbative and non-perturbative aspects in vector model/higher spin duality J. Phys. A: Math. Theor. 46 214005 (arXiv:1212.5215 [hep-th]) [16] Iazeolla C Sundell P 2013 Biaxially symmetric solutions to 4D higher-spin gravity J. Phys. A: Math. Theor. 46 214004 (arXiv:1208.4077 [hep-th]) [17] Ammon M, Gutperle M, Kraus P Perlmutter E 2013 Black holes in three dimensional higher spin gravity: a review J. Phys. A: Math. Theor. 46 214001 (arXiv:1208.5182 [hep-th]) [18] Sagnotti A 2013 Notes on strings and higher spins J. Phys. A: Math. Theor. 46 214006 (arXiv:1112.4285 [hep-th])
NASA Astrophysics Data System (ADS)
Vilitis, O.; Titavs, E.; Nitiss, E.; Rutkis, M.
2013-02-01
The corona discharge is described focusing on the advantages of corona triode techniques for the direct current (DC) positive poling of optical polymers. The proposed experimental setup allows the corona poling of nonlinear optical (NLO) polymers in the modes of DC constant current (the lowest 1nA) and of the fixed corona-grid voltage, making it possible to carry out the corona-onset poling at elevated temperature (COPET) up to 200 oC. The setup also provides a wide range of the corona discharge voltage (3 kV - 15 kV), variable reciprocal distance of electrodes as well as the possibility to choose from different types of the corona electrode (needle, multi-needle, wire, etc.). By keeping the corona-to-grid voltage constant, a stable corona discharge at electrode is attained. The grid voltage can be varied in the range from 0 to 3kV. The corona poling area on the sample surface is pre-defined by placing ring spacers above it. The setup is completely computerized, allowing both control and monitoring of the corona discharge, which promotes research into the process of charging NLO polymer samples and selection of the optimal poling mode. Using the voltage-current characteristics and the second-harmonic measurements of a poled polymer we also demonstrate the influence of the setup parameters on the efficiency of poling the thin film NLO polymers. Darba ievadā īsumā aprakstīta koronas izlāde, izceļot koronas triodes theniskās metodes lietošanas priekšrocības optisko polimeru polarizēšanā ar pozitīvās koronas līdzstrāvu. Rakstā apskatīta eksperimentāla koronas polēšanas ierīce, kas sniedz iespēju polarizēt nelineāros optiskos (NLO) polimērus pie konstantas strāvas (līdz pat 1 nA) un fiksēta koronas elektroda-tīkliņa sprieguma, ļaujot veikt polēšanu paaugstinātās temperatūrās līdz 200 oC. Ierīcē paredzētas plašas koronas izlādes sprieguma izvēles robežas (3-15 kV), iespējas mainīt elektrodu savstarpējo izvietojumu un izvēlēties dažādus koronas elektrodu veidus (adatu, vairākas adatas, stiepli). Ir iespējams nodrošināt pastāvīgu koronas elektroda darba režīmu, saglabājot konstantu spriegumu starp koronas elektrodu un tīkliņu pie tīkliņa sprieguma izmainīšanas iespējām robežās no 0-3 kV. Parauga virsmas polarizēšanas laukumu var mainīt ar gredzenveida starplikām, ko novieto virs parauga virsmas. Ierīce ir pilnībā datorizēta, kas ļauj sekot koronas izlādes gaitai, to vadīt un reģistrēt rezultātus. Tas savukārt uzlabo NLO polimēru paraugu uzlādēšanas procesu pētījumu kvalitāti un ļauj veiksmīgāk noteikt optimālāko polarizēšanas režīmu. Izmantojot strāvas-sprieguma raksturlīknes un polarizēto polimēru otrās harmonikas mērījumus, var arī uzskatāmi parādīt, kā polarizēšanas ierīces un tās darba režīma parametri ietekmē polarizēto plāno kārtiņu NLO efektivitāti.
Eshleman, Jodi L.; Barnard, Patrick L.; Erikson, Li H.; Hanes, Daniel M.
2007-01-01
Coastal managers have faced increasing pressure to manage their resources wisely over the last century as a result of heightened development and changing environmental forcing. It is crucial to understand seasonal changes in beach volume and shape in order to identify areas vulnerable to accelerated erosion. Shepard (1950) was among the first to quantify seasonal beach cycles. Sonu and Van Beek (1971) and Wright et al. (1985) described commonly occurring beach states. Most studies utilize widest spaced 2-D cross shore profiles or shorelines extracted from aerial photographs (e.g. Winant et al. 1975; Aubrey, 1979, Aubrey and Ross, 1985; Larson and Kraus, 1994; Jimenez et al., 1977; Lacey and Peck, 1998; Guillen et al., 1999; Norcorss et al., 2002) to analyzed systematic changes in beach evolution. But with the exception of established field stations, such as Duck, NC (Birkemeier and Mason, 1984), ans Hazaki Oceanographical Research Station (HORS) in Japan (Katoh, 1997), there are very few beach change data sets with high temporal and spatial resolutions (e.g. Dail et al., 2000; Ruggiero et al., 2005; Yates et al., in press). Comprehensive sets of nearshore morphological data and local in situ measurements outside of these field stations are very rare and virtually non-existent high-energy coasts. Studied that have attempted to relate wave statistics to beach morphology change require some knowledge of the nearshore wave climate, and have had limited success using offshore measurement (Sonu and Van Beek, 1971; Dail et al., 2000). The primary objective of this study is to qualitatively compare spatially variable nearshore wave predictions to beach change measurements in order to understand the processes responsible for a persistent erosion 'hotspot' at Ocean Beach, San Francisco, CA. Local wave measurements are used to calibrate and validate a wave model that provides nearshore wave prediction along the beach. The model is run for thousands of binned offshore wave conditions to help isolate the effects of offshore wave direction and period on nearshore wave predictions. Alongshore varying average beach change statistics are computed at specific profile locations from topographic beach surveys and lidar data. The study area is located in the San Francisco Bight in central California. Ocean Beach is a seven kilometer long north-south trending sandy coastline located just south of the entrance to the San Francisco Bay Estuary (Figure 1). It contains an erosion hotspot in the southern part of the beach which has resulted in damage to local infrastructure and is the cause of continued concern. A wide range of field data collection and numerical modeling efforts have been focused here as part of the United States Geological Survey's (USGS) San Francisco Bight Coastal Processes Study, which began in October 2003 and represents the first comprehensive study of coastal processes at the mouth of San Francisco Bay. Ocean Beach is exposed to very strong tidal flows, with measured currents often in excess of 1 m/s at the north end of the beach. Current profiler measurements indicate that current magnitudes are greater in the northern portion of the beach, while wave energy is greater in the southern portion where erosion problems are greatest (Barnard et al., 2007). The sub-aerial beach volume fluctuates seasonally over a maximum envelope of 400,000 m3 for the seven kilometer stretch (Barnard et al, 2007). The wave climate in the region is dominated by an abundance of low frequency energy (greater than 20 s period) and prevailing northwest incident wave angles. The application of a wave model to the region is further complicated by the presence of the Farallon Islands 40 kilometers west, and a massive ebb tidal delta at the mouth of San Francisco Bay (~150 km2), which creates complicated refraction patterns as wave energy moves from offshore Ocean Beach; however the cost and threat of the energetic nearshore environment have limited the temporal and spatial resolution of these measurements. Applying numerical models to predict wave and current patterns along the beach can help supplement the filed data that exists and provide opportunities to make prediction about the impacts of changing environmental forcing.
DISR imaging and the geometry of the descent of the Huygens probe within Titan's atmosphere
NASA Astrophysics Data System (ADS)
Karkoschka, Erich; Tomasko, Martin G.; Doose, Lyn R.; See, Chuck; McFarlane, Elisabeth A.; Schröder, Stefan E.; Rizk, Bashar
2007-11-01
The Descent Imager/Spectral Radiometer (DISR) provided 376 images during the descent to Titan and 224 images after landing. Images of the surface had scales between 150 m/pixel and 0.4 mm/pixel, all of which we assembled into a mosaic. The analysis of the surface and haze features in these images and of other data gave tight constraints on the geometry of the descent, particularly the trajectory, the tip and tilt, and the rotation of the Huygens probe. Huygens moved on average in the direction of 2∘ north of east from 145 to 50 km altitude, turning to 5∘ south of east between 30 and 20 km altitude, before turning back to east. At 6.5 km altitude, it reversed to WNW, before reversing back to SE at 0.7 km altitude. At first, Huygens was tilting slowly by up to 15∘ as expected for a descent through layers of changing wind speeds. As the winds calmed, tilts decreased. Tilts were approximately retrieved throughout the main-parachute phase, but only for 160 specific times afterwards. Average swing rates were 5∘/s at high and low altitudes, but 13∘/s between 110 and 30 km altitude. Maximum swing rates were often above 40∘/s, far above the design limit of 6∘/s, but they caused problems only for a single component of DISR, the Sun Sensor. The excitation of such high swing rates on the stabilizer parachute is not fully understood. Before the parachute exchange, the rotational rate of Huygens smoothly approached the expected equilibrium value of 3 rotations per vertical kilometer, although clockwise instead of counterclockwise. Starting at 40 s after the parachute exchange until landing, Huygens rotated erratically. Long-term averages of the rotational rate varied between 2.0 and 4.5 rotations/km. On time scales shorter than a minute, some 100 strong rotational accelerations or decelerations created azimuthal irregularities of up to 180∘, which caused DISR to take most exposures at random azimuths instead of pre-selected azimuths. Nevertheless, we reconstructed the azimuths throughout the 360 rotations during the descent and for each of some 3500 DISR exposures with a typical accuracy near 2∘. Within seconds after landing, the parachute moved into the field of view of one of the spectrometers. The observed light curve indicated a motion of the parachute of 0.3 m/s toward the SSE. DISR images indicated that the probe did not penetrate into the surface, assuming a level ground. This impact of Huygens must have occurred on major rocks or some elevated area. The unexpected raised height increases ice-rock sizes by 40% with respect to estimations made in 2005 [Tomasko, M.G., Archinal, B., Becker, T., Bézard, B., Bushroe, M., Combes, M., Cook, D., Coustenis, A., de Bergh, C., Dafoe, L.E., Doose, L., Douté, S., Eibl, A., Engel, S., Gliem, F., Grieger, B., Holso, K., Howington-Kraus, E., Karkoschka, E., Keller, H.U., Kirk, R., Kramm, R., Küppers, M., Lanagan, P., Lellouch, E., Lemmon, M., Lunine, J., McFarlane, E., Moores, J., Prout, G.M., Rizk, B., Rosiek, M., Rueffer, P., Schröder, S.E., Schmitt, B., See, C., Smith, P., Soderblom, L., Thomas, N., West, R., 2005. Rain, winds and haze during the Huygens probe's descent to Titan's surface. Nature 438, 765-778]. During the 70-min surface phase, the tilt of Huygens was 3∘, changing by a small fraction of a degree. The apparent horizon looking south to SSW from the landing site was 1- 2∘ above the theoretical horizon, sloping by 1∘ up to the left (east). Our best guess puts the horizon as a 1-2 m high hill in 30-50 m distance. We detected the refraction from warm, rising air bubbles above our illuminated spot. Bright, elongated, cm-sized objects appear occasionally on the surface. If real, they could be rain drop splashes or fluffy particles blown across Titan's surface.
The enigma of the Australian Alps, young landscapes and missing cryogenic features.
NASA Astrophysics Data System (ADS)
Slee, Adrian; Shulmeister, James; Clark, Doug
2014-05-01
Widespread evidence for pre last glacial cycle glaciation of late Quaternary ages has been documented from mid-latitude southern hemisphere mountain environments in New Zealand, southern South America and the Tasmanian Highlands. On mainland Australia however cirque and small valley glaciation in the Australian Alps is limited to OIS 4-3 and the last glacial maximum (OIS 2) (Barrows et al. 2001). This contrasts with the other southern hemisphere glacial records that indicate significantly more extensive glaciations preceding the last glacial cycle. In both the Southern Andes and Tasmania the maximum glaciations occurred prior to 783 kya (Glasser et al. 2008, Colhoun et al. 2010) while in tectonically active New Zealand it is at least clear that the scale of glaciation has been diminishing over the last 3 glacial cycles (Shulmeister et al. 2010). In all these locations early workers argued for extensive ice coverage, but subsequent investigations limited the extent and number of glacial advances before more recent work has locally re-extended the glacial limits and greatly increased the number of glacial advances. Similarly, in the highlands of SE Australia the possibility of more pervasive ice coverage was initially entertained; but since the 1960s and especially the 1980s the general consensus is that the lack of glacial evidence is a result of cold dry conditions prevailing for much of the Quaternary on the Australian Alps (Reeves et al. 2013) Recent work by the authors on the extent of relict periglacial block deposits in Australia have identified these block deposits as far north as 29°30'S on the Great Dividing Range, confirming strong freeze-thaw conditions well into the sub-tropics at moderate (900-1200 m) elevations. Curiously, however, the same mapping work has also highlighted the limited development of block deposits and other freeze-thaw landforms, such as tors, in the highest regions of the Australian Alps, in areas beyond the known limits of glaciation. It is also noteworthy that the periglacial features on mainland SE Australia that have absolute ages relate primarily to the last glacial maximum (Barrows et al. 2004). This again contrasts with Tasmania were the periglacial features are both associated with multiple ice ages and are often polygenetic. This presentation reviews geomorphic evidence from two of the highest regions of SE Australia (Bogong High Plains and the Kosciuszko Massif) to determine the extent and nature of cryogenic landscape features in these areas. It will attempt to resolve questions both about the nature of processes operating in these landscapes and add to the debate about the curious paucity of pre-last glacial landscapes at high elevations in SE Australia. References: Barrows, T.T., Stone, J.O., Fifield, L.K. and Cresswell, R.G., 2001. Late Pleistocene glaciation of the Kosciuszko Massif, Snowy Mountains, Australia. Quaternary Research, 55: 179-189 Barrows, T.T., Stone, J. O. and Fifield. L.K, 2004. Exposure ages for Plestocene periglacial deposits in Australia. Quaternary Science Reviews, Vol. 23 (5-6): 697-708 Colhoun, E.A., Kiernan, K., Barrows, T.T. and Geode, A., 2010, Advances in Quaternary studies in Tasmania. Geological Society, London, Special Publications 346:121-139 Glasser, N.F., Jansson, K.N., Harrison, S. and Klenman, J., 2008. The glacial geomorphology and Pleistocene history of South America between 38°S and 56°S. Quaternary Science Reviews 27 (3-4): 365-390 Reeves, J.M., Barrows, T.T., Cohen, T.J., Kiem, A.S., Bostock, H.C., Fitzsimmons, K.E., Jansen, J.D., Kemp, J., Krause, C., Petherick, L. and Phipps, S.J., Climate variability over the last 35,000 years recorded in marine and terrestrial archives in the Australian region: an OZ-INTIMATE compilation. Quaternary Science Reviews 74: 21-34 Shulmeister, J, Thackray, G.D., Rieser, U, Hyatt, O.M, Rother, H., C.C. Smart, and D.J.A. Evans 2010. The stratigraphy, timing and climatic implications of glacilacustrine deposits in the middle Rakaia Valley, South Island, New Zealand. Quaternary Science Reviews 29:2362-2381.
NASA Astrophysics Data System (ADS)
Magee, Jeff; Moffett, Jonathan
1996-06-01
Special Issue on Management This special issue contains seven papers originally presented at an International Workshop on Services for Managing Distributed Systems (SMDS'95), held in September 1995 in Karslruhe, Germany. The workshop was organized to present the results of two ESPRIT III funded projects, Sysman and IDSM, and more generally to bring together work in the area of distributed systems management. The workshop focused on the tools and techniques necessary for managing future large-scale, multi-organizational distributed systems. The open call for papers attracted a large number of submissions and the subsequent attendance at the workshop, which was larger than expected, clearly indicated that the topics addressed by the workshop were of considerable interest both to industry and academia. The papers selected for this special issue represent an excellent coverage of the issues addressed by the workshop. A particular focus of the workshop was the need to help managers deal with the size and complexity of modern distributed systems by the provision of automated support. This automation must have two prime characteristics: it must provide a flexible management system which responds rapidly to changing organizational needs, and it must provide both human managers and automated management components with the information that they need, in a form which can be used for decision-making. These two characteristics define the two main themes of this special issue. To satisfy the requirement for a flexible management system, workers in both industry and universities have turned to architectures which support policy directed management. In these architectures policy is explicitly represented and can be readily modified to meet changing requirements. The paper `Towards implementing policy-based systems management' by Meyer, Anstötz and Popien describes an approach whereby policy is enforced by event-triggered rules. Krause and Zimmermann in their paper `Implementing configuration management policies for distributed applications' present a system in which the configuration of the system in terms of its constituent components and their interconnections can be controlled by reconfiguration rules. Neumair and Wies in the paper `Case study: applying management policies to manage distributed queuing systems' examine how high-level policies can be transformed into practical and efficient implementations for the case of distributed job queuing systems. Koch and Krämer in `Rules and agents for automated management of distributed systems' describe the results of an experiment in using the software development environment Marvel to provide a rule based implementation of management policy. The paper by Jardin, `Supporting scalability and flexibility in a distributed management platform' reports on the experience of using a policy directed approach in the industrial strength TeMIP management platform. Both human managers and automated management components rely on a comprehensive monitoring system to provide accurate and timely information on which decisions are made to modify the operation of a system. The monitoring service must deal with condensing and summarizing the vast amount of data available to produce the events of interest to the controlling components of the overall management system. The paper `Distributed intelligent monitoring and reporting facilities' by Pavlou, Mykoniatis and Sanchez describes a flexible monitoring system in which the monitoring agents themselves are policy directed. Their monitoring system has been implemented in the context of the OSIMIS management platform. Debski and Janas in `The SysMan monitoring service and its management environment' describe the overall SysMan management system architecture and then concentrate on how event processing and distribution is supported in that architecture. The collection of papers gives a good overview of the current state of the art in distributed system management. It has reached a point at which a first generation of systems, based on policy representation within systems and automated monitoring systems, are coming into practical use. The papers also serve to identify many of the issues which are open research questions. In particular, as management systems increase in complexity, how far can we automate the refinement of high-level policies into implementations? How can we detect and resolve conflicts between policies? And how can monitoring services deal efficiently with ever-growing complexity and volume? We wish to acknowledge the many contributors, besides the authors, who have made this issue possible: the anonymous reviewers who have done much to assure the quality of these papers, Morris Sloman and his Programme Committee who convened the Workshop, and Thomas Usländer and his team at the Fraunhofer Institute in Karlsruhe who acted as hosts.
NASA Astrophysics Data System (ADS)
Radtke, T.; Fritzsche, S.
2008-11-01
Entanglement is known today as a key resource in many protocols from quantum computation and quantum information theory. However, despite the successful demonstration of several protocols, such as teleportation or quantum key distribution, there are still many open questions of how entanglement affects the efficiency of quantum algorithms or how it can be protected against noisy environments. The investigation of these and related questions often requires a search or optimization over the set of quantum states and, hence, a parametrization of them and various other objects. To facilitate this kind of studies in quantum information theory, here we present an extension of the FEYNMAN program that was developed during recent years as a toolbox for the simulation and analysis of quantum registers. In particular, we implement parameterizations of hermitian and unitary matrices (of arbitrary order), pure and mixed quantum states as well as separable states. In addition to being a prerequisite for the study of many optimization problems, these parameterizations also provide the necessary basis for heuristic studies which make use of random states, unitary matrices and other objects. Program summaryProgram title: FEYNMAN Catalogue identifier: ADWE_v4_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWE_v4_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 24 231 No. of bytes in distributed program, including test data, etc.: 1 416 085 Distribution format: tar.gz Programming language: Maple 11 Computer: Any computer with Maple software installed Operating system: Any system that supports Maple; program has been tested under Microsoft Windows XP, Linux Classification: 4.15 Does the new version supersede the previous version?: Yes Nature of problem: During the last decades, quantum information science has contributed to our understanding of quantum mechanics and has provided also new and efficient protocols, based on the use of entangled quantum states. To determine the behavior and entanglement of n-qubit quantum registers, symbolic and numerical simulations need to be applied in order to analyze how these quantum information protocols work and which role the entanglement plays hereby. Solution method: Using the computer algebra system Maple, we have developed a set of procedures that support the definition, manipulation and analysis of n-qubit quantum registers. These procedures also help to deal with (unitary) logic gates and (nonunitary) quantum operations that act upon the quantum registers. With the parameterization of various frequently-applied objects, that are implemented in the present version, the program now facilitates a wider range of symbolic and numerical studies. All commands can be used interactively in order to simulate and analyze the evolution of n-qubit quantum systems, both in ideal and noisy quantum circuits. Reasons for new version: In the first version of the FEYNMAN program [1], we implemented the data structures and tools that are necessary to create, manipulate and to analyze the state of quantum registers. Later [2,3], support was added to deal with quantum operations (noisy channels) as an ingredient which is essential for studying the effects of decoherence. With the present extension, we add a number of parametrizations of objects frequently utilized in decoherence and entanglement studies, such that as hermitian and unitary matrices, probability distributions, or various kinds of quantum states. This extension therefore provides the basis, for example, for the optimization of a given function over the set of pure states or the simple generation of random objects. Running time: Most commands that act upon quantum registers with five or less qubits take ⩽10 seconds of processor time on a Pentium 4 processor with ⩾2GHz or newer, and about 5-20 MB of working memory (in addition to the memory for the Maple environment). Especially when working with symbolic expressions, however, the requirements on CPU time and memory critically depend on the size of the quantum registers, owing to the exponential growth of the dimension of the associated Hilbert space. For example, complex (symbolic) noise models, i.e. with several symbolic Kraus operators, result for multi-qubit systems often in very large expressions that dramatically slow down the evaluation of e.g. distance measures or the final-state entropy, etc. In these cases, Maple's assume facility sometimes helps to reduce the complexity of the symbolic expressions, but more often only a numerical evaluation is possible eventually. Since the complexity of the various commands of the FEYNMAN program and the possible usage scenarios can be very different, no general scaling law for CPU time or the memory requirements can be given. References: [1] T. Radtke, S. Fritzsche, Comput. Phys. Comm. 173 (2005) 91. [2] T. Radtke, S. Fritzsche, Comput. Phys. Comm. 175 (2006) 145. [3] T. Radtke, S. Fritzsche, Comput. Phys. Comm. 176 (2007) 617.
Simulation of n-qubit quantum systems. V. Quantum measurements
NASA Astrophysics Data System (ADS)
Radtke, T.; Fritzsche, S.
2010-02-01
The FEYNMAN program has been developed during the last years to support case studies on the dynamics and entanglement of n-qubit quantum registers. Apart from basic transformations and (gate) operations, it currently supports a good number of separability criteria and entanglement measures, quantum channels as well as the parametrizations of various frequently applied objects in quantum information theory, such as (pure and mixed) quantum states, hermitian and unitary matrices or classical probability distributions. With the present update of the FEYNMAN program, we provide a simple access to (the simulation of) quantum measurements. This includes not only the widely-applied projective measurements upon the eigenspaces of some given operator but also single-qubit measurements in various pre- and user-defined bases as well as the support for two-qubit Bell measurements. In addition, we help perform generalized and POVM measurements. Knowing the importance of measurements for many quantum information protocols, e.g., one-way computing, we hope that this update makes the FEYNMAN code an attractive and versatile tool for both, research and education. New version program summaryProgram title: FEYNMAN Catalogue identifier: ADWE_v5_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWE_v5_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 27 210 No. of bytes in distributed program, including test data, etc.: 1 960 471 Distribution format: tar.gz Programming language: Maple 12 Computer: Any computer with Maple software installed Operating system: Any system that supports Maple; the program has been tested under Microsoft Windows XP and Linux Classification: 4.15 Catalogue identifier of previous version: ADWE_v4_0 Journal reference of previous version: Comput. Phys. Commun. 179 (2008) 647 Does the new version supersede the previous version?: Yes Nature of problem: During the last decade, the field of quantum information science has largely contributed to our understanding of quantum mechanics, and has provided also new and efficient protocols that are used on quantum entanglement. To further analyze the amount and transfer of entanglement in n-qubit quantum protocols, symbolic and numerical simulations need to be handled efficiently. Solution method: Using the computer algebra system Maple, we developed a set of procedures in order to support the definition, manipulation and analysis of n-qubit quantum registers. These procedures also help to deal with (unitary) logic gates and (nonunitary) quantum operations and measurements that act upon the quantum registers. All commands are organized in a hierarchical order and can be used interactively in order to simulate and analyze the evolution of n-qubit quantum systems, both in ideal and noisy quantum circuits. Reasons for new version: Until the present, the FEYNMAN program supported the basic data structures and operations of n-qubit quantum registers [1], a good number of separability and entanglement measures [2], quantum operations (noisy channels) [3] as well as the parametrizations of various frequently applied objects, such as (pure and mixed) quantum states, hermitian and unitary matrices or classical probability distributions [4]. With the current extension, we here add all necessary features to simulate quantum measurements, including the projective measurements in various single-qubit and the two-qubit Bell basis, and POVM measurements. Together with the previously implemented functionality, this greatly enhances the possibilities of analyzing quantum information protocols in which measurements play a central role, e.g., one-way computation. Running time: Most commands require ⩽10 seconds of processor time on a Pentium 4 processor with ⩾2 GHz RAM or newer, if they work with quantum registers with five or less qubits. Moreover, about 5-20 MB of working memory is typically needed (in addition to the memory for the Maple environment itself). However, especially when working with symbolic expressions, the requirements on the CPU time and memory critically depend on the size of the quantum registers owing to the exponential growth of the dimension of the associated Hilbert space. For example, complex (symbolic) noise models, i.e. with several Kraus operators, may result in very large expressions that dramatically slow down the evaluation of e.g. distance measures or the final-state entropy, etc. In these cases, Maple's assume facility sometimes helps to reduce the complexity of the symbolic expressions, but more often than not only a numerical evaluation is feasible. Since the various commands can be applied to quite different scenarios, no general scaling rule can be given for the CPU time or the request of memory. References:[1] T. Radtke, S. Fritzsche, Comput. Phys. Commun. 173 (2005) 91.[2] T. Radtke, S. Fritzsche, Comput. Phys. Commun. 175 (2006) 145.[3] T. Radtke, S. Fritzsche, Comput. Phys. Commun. 176 (2007) 617.[4] T. Radtke, S. Fritzsche, Comput. Phys. Commun. 179 (2008) 647.
NASA Astrophysics Data System (ADS)
Friedrich, Jana; van Beusekom, Justus E. E.; Neumann, Andreas; Naderipour, Celine; Janssen, Felix; Ahmerkamp, Soeren; Holtappels, Moritz; Schueckel, Ulrike
2016-04-01
The southern North Sea, and the German Bight, has been systematically bottom-trawled at least since the late 19th century (Christiansen, 2009; Reiss et al., 2009; Kröncke 2011; Emeis et al., 2015, Neumann et al., 2016). As a result, benthic habitats and benthic biogenic structures created by bivalves, polychaetes and hydroids where destroyed or reduced. The parallel removal of hard substrate (gravel and boulders) avoids the resettlement of hard-substrate depended species. For example, the Oyster ground, a huge oyster bank a hundred years ago (Olsen, 1883), turned into a muddy depression today. In addition, shallow depth of max 40 m, strong tidal currents and frequent storms result in a high-energy environment with low sedimentation rates and recurrent sediment resuspension. The decrease in benthic filtering capacity by disturbance in epifauna and bottom roughness (Callaway et al., 2007) apparently influence pelagic-benthic coupling of biogeochemical fluxes. Heip et al. (1995) indicate that benthic respiration at depths prevailing in the German Bight accounts for 10-40% of total respiration, whereas pelagic respiration accounts for 60-90%. Previous estimates are in the middle of this range (Heip et al., 1995). To test these hypotheses and to assess the partitioning of benthic and pelagic processes, and the factors influencing organic matter mineralization, we measured pelagic production and respiration based on Winkler titration, in-situ benthic fluxes using chamber landers, we did ex-situ incubations of intact sediment cores and analysed still images from a towed benthic video sled. In addition, O2 fluxes in permeable sediments were estimated by integrating the volumetric rate measurements of the upper sediment layer over in-situ microsensor-measured O2 penetration depth. Our current results show significant seasonality in benthic respiration, with highest rates in summer and lowest rates in winter. No significant differences in total benthic respiration rates were measured on sandy (permeable) and silty (diffusive) sediments, whereas significant differences of microbial O2 uptake were observed indeed between permeable and diffusive sediments. Nevertheless, when considering the multitude of different methods, we found that benthic respiration over the season seemed to be governed mainly by settling of fresh organic matter during calm periods and its rapid turnover in a region where strong tidal and wind-forced currents distribute suspended particles over large areas. Summer pelagic respiration rates were an order of magnitude higher then benthic rates, and account for 88-93% of total respiration, which represents 79-98% of pelagic primary production. Our measurements of benthic respiration account for 7-12% of the total in the German Bight, which is lower compared to earlier studies. Strong tidal and wind-forced currents along with the lack of complex three-dimensional biogenic structures seem to prevent settling of suspended matter and foster resuspension, thereby supporting pelagic turnover processes. Hence, we assume that benthic turnover might have been higher before systematic bottom trawling destroyed the bottom hydrobiological regime. Today, due to the strong current regime in the German Bight, the pelagic system appears to be a largely closed system of production and respiration, with comparably little for export to the benthic system due to absence of biogenic structures. References Callaway R, Engelhard GH, Dann J, Cotter J, Rumohr H (2007) One century of North Sea epibenthos and fishing: comparison between 1902-1912, 1982-1985 and 2000. Marine Ecology Progress Series 346, 27-43. Christiansen S (2009) Towards good environmental status - A network of marine protected areas for the North Sea. In: Lutter S (ed) WWF Germany, Fankfurt/Main Emeis K-C, van Beusekom J, Callies U, Ebinghaus R, Kannen A, Kraus G, Kröncke I, Lenhart H, Lorkowski I, Matthias V, Möllmann C, Pätsch J, Scharfe M, Thomas H, Weisse R, Zorita E (2015) The North Sea -A shelf sea in the Anthropocene. Journal of Marine Systems 141:18-33 Heip CHR, Goosen NK, Herman PMJ, Kromkamp J, Middelburg JJ, Soetaerd K (1995) Production and consumption of biological particles in temperate tidal estuaries. Oceanography and Marine Biology: an Annual Review 33:1-149 Kröncke I (2011) Changes in Dogger Bank macrofauna communities in the 20th century caused by fishing and climate. Estuarine, Coastal and Shelf Sciences 94 (3): 234-245. Neumann H, Diekmann R, Kröncke I (2016) The influence of habitat characteristics and fishing effort on functional composition of epifauna in the south-eastern North Sea. Estuarine, Coastal and Shelf Sciences 169: 182-194. Olsen OT (1883) The Piscatorial Atlas of the North Sea, English and St. George's Channels. Taylor and Francis, London Reiss H, Greenstreet S, Sieben K, Ehrich S, Piet G, Quirijns F, Robinson F, Wolff W, Kröncke I (2009) Effects of fishing disturbance on benthic communities and secondary production within an intensively fished area. Marine Ecology Progress Series 394:201-213
VizieR Online Data Catalog: Follow-up photometry and spectroscopy of KELT-17 (Zhou+, 2016)
NASA Astrophysics Data System (ADS)
Zhou, G.; Rodriguez, J. E.; Collins, K. A.; Beatty, T.; Oberst, T.; Heintz, T. M.; Stassun, K. G.; Latham, D. W.; Kuhn, R. B.; Bieryla, A.; Lund, M. B.; Labadie-Bartz, J.; Siverd, R. J.; Stevens, D. J.; Gaudi, B. S.; Pepper, J.; Buchhave, L. A.; Eastman, J.; Colon, K.; Cargile, P.; James, D.; Gregorio, J.; Reed, P. A.; Jensen, E. L. N.; Cohen, D. H.; McLeod, K. K.; Tan, T. G.; Zambelli, R.; Bayliss, D.; Bento, J.; Esquerdo, G. A.; Berlind, P.; Calkins, M. L.; Blancato, K.; Manner, M.; Samulski, C.; Stockdale, C.; Nelson, P.; Stephens, D.; Curtis, I.; Kielkopf, J.; Fulton, B. J.; Depoy, D. L.; Marshall, J. L.; Pogge, R.; Gould, A.; Trueblood, M.; Trueblood, P.
2017-05-01
KELT-17, the first exoplanet host discovered through the combined observations of both the Kilodegree Extremely Little Telescope (KELT)-North and KELT-South, is located in KELT-South field 06 (KS06) and KELT-North field 14 (KN14), which are both centered on α=07h39m36s δ=+03°00'00'' (J2000). At the time of identification, the post-processed KELT data set included 2092 images from KN14, taken between UT 2011 October 11 and UT 2013 March 26 and 2636 images from KS06 taken between UT 2010 March 02 and 2013 May 10. The discovery light curves from both KELT-North and KELT-South are shown in Figure1. We obtained higher spatial resolution and precision photometric follow-up observations of KELT-17b in multiple filters. An I-band transit was observed on UT 2015 March 05 at the Canela's Robotic Observatory (CROW) with the 0.3m SCT12 telescope, remotely operated from Portalegre, Portugal. Observations were acquired with the ST10XME CCD camera, with a 30'*20' field of view and a 0.86'' pixel scale. A full multi-color (V and I) transit of KELT-17b was observed on UT 2015 March 12 at Kutztown University Observatory (KUO), located on the campus of Kutztown University in Kutztown, Pennsylvania. KUO's main instrument is the 0.6 m Ritchey-Chretien optical telescope with a focal ratio of f/8. The imaging CCD (KAF-6303E) camera has an array of 3K*2K (9μm) pixels and covers a field of view of 19.5'*13.0'. The Peter van de Kamp Observatory (PvdK) at Swarthmore College (near Philadelphia) houses a 0.62m Ritchey-Chretien reflector with a 4K*4K pixel Apogee CCD. The telescope and camera together have a 26'*26' field of view and a 0.61'' pixel scale. PvdK observed KELT-17b on UT 2015 March 12 in the SDSS z' filter. KELT-17b was observed in both g' and i' on UT 2015 March 12 at Wellesley College's Whitin Observatory in Massachusetts. The telescope is a 0.6m Boller and Chivens with a DFM focal reducer yielding an effective focal ratio of f/9.6. We used an Apogee U230 2K*2K camera with a 0.58''/pixel scale and a 20'*20' field of view. One full transit of KELT-17b was observed from the Westminster College Observatory (WCO), PA, on UT 2015 November 4 in the z' filter. The observations employed a 0.35m f/11 Celestron C14 Schmidt-Cassegrain telescope and SBIG STL-6303E CCD with a ~3K*2K array of 9μm pixels, yielding a 24'*16' field of view and 1.4''/pixel image scale at 3*3 pixel binning. The stellar FWHM was seeing-limited with a typical value of ~3.2''. Three full transits of KELT-17b were observed on UT 2016 February 26 (g' and i') and UT 2016 March 31 (r') using the Manner-Vanderbilt Ritchie-Chrtien (MVRC) telescope located at the Mt. Lemmon summit of Steward Observatory, AZ. The observations employed a 0.6m f/8 RC Optical Systems Ritchie-Chretien telescope and SBIG STX-16803 CCD with a 4K*4K array of 9μm pixels, yielding a 26'*26' field of view and 0.39''/pixel image scale. The telescope was heavily defocused for all three observations resulting in a typical stellar FWHM of ~17''. The Perth Exoplanet Survey Telescope (PEST) observatory is a backyard observatory owned and operated by ThiamGuan (TG) Tan, located in Perth, Australia. It is equipped with a 0.3m Meade LX200 SCT f/10 telescope with focal reducer yielding f/5 and an SBIG ST-8XME CCD camera. The telescope and camera combine to have a 31'*21' field of view and a 1.2'' pixel scale. PEST observed KELT-17b on UT 2016 March 06 in the B band. A series of spectroscopic follow-up observations were performed to characterize the KELT-17 system. We performed low-resolution, high-signal-to-noise reconnaissance spectroscopic follow-up of KELT-17 using the Wide Field Spectrograph (WiFeS) on the Australian National University (ANU) 2.3m telescope at Siding Spring Observatory, Australia in 2015 February. In-depth spectroscopic characterization of KELT-17 was performed by the Tillinghast Reflector Echelle Spectrograph (TRES) on the 1.5m telescope at the Fred Lawrence Whipple Observatory, Mount Hopkins, Arizona, USA. TRES has a wavelength coverage of 3900-9100Å over 51 echelle orders, with a resolving power of λ/Δλ R=44000. A total of 12 out-of-transit observations were taken to characterize the radial velocity orbital variations exhibited by KELT-17. In addition, we also observed spectroscopic transits of KELT-17b with TRES on 2016 February 23 and 2016 February 26 UT, gathering 33 and 29 sets of spectra, respectively. (4 data files).
Especially for High School Teachers
NASA Astrophysics Data System (ADS)
Howell, J. Emory
1999-08-01
Care to Share? An Informal Syllabus Exchange A recent email message from Thomas Shiland, who teaches at Saratoga Springs Senior High School, noted that the process of revising the high school chemistry syllabus is underway in New York State. He expressed a strong interest in helping construct a chemistry syllabus that represents the best thinking about appropriate content. He wondered if it would be possible to develop a way in which different secondary chemistry syllabi could easily be exchanged. It is likely that readers from other states and countries are involved in a similar process and might also be interested in exchanging syllabi. Many states do not use the term syllabus to describe their guiding curricular document for chemistry but rather refer to it as a framework or as guidelines. In most cases, the document includes a list of key ideas or topics, performance indicators, and the major understandings associated with each key idea. Such documents would be appropriate for exchange among those of you involved in the revision process. If you are interested in arranging an exchange please contact me by email at j.e.howell@usm.edu or by mail at J. E. Howell, Box 5043, USM, Hattiesburg, MS39406-5043, USA. High School Day Information The High School Chemistry Program at the American Chemical Society National Meeting in New Orleans, Louisiana will be held Sunday, August 22, 1999, at the Doubletree Hotel, 300 Canal Street. If you wish to register only for the High School Day activities, which includes a pass to the ACS Exposition, a special registration form is available from Lillie Tucker-Akin, 2800 Reynard Dr., Tupelo, MS38801; sci4me@aol.com; fax: 662/566-7906. Advance registration is 25 and the cost of the High School Luncheon is 12. Register in advance by August 1, 1999, or from 7:45 to 8:30 a.m. at the High School Day table in the conference room area of the Doubletree. The workshop schedule is shown below. Secondary School Feature Articles * Exploring the Ocean-Stating the Case for Chemistry, by Paul J. Scheuer, p 1075 * Distillation Apparatuses Using Household Items, by Danielle R. D. Campanizzi, Brenda Mason, Christine K. F. Hermann, p 1079 New Orleans Concurrent Workshops, High School Program 8:30 a.m.-9:20 a.m. A. A Teaching Resource for You: The Journal of Chemical Education, J. E. Howell, J. W. Moore, and A. M. Sarquis B. Electrical Conductivity, J. M. Manion and P. F. Krause, and The Properties of Gases, J.-M. Whitfield and K. A. Woodling C. Chemistry with Calculators for Beginners, P. Sconzo (3 hours) D. Spectrum of Activities for Chemistry Teachers, Carolina Biological Supply, S. Mitchell, F. Cherry, and L. Akin (3 hours) 9:30 a.m.-10:20 a.m. A. Applying Chemical Education Research to the Classroom, L. Akin and J. Valasek B. Another Look at the Deflection of Falling Liquids, H. H. Harris and J. Newstrum, and Encouraging Students to Investigate Acids and Bases Using Plant Indicators, P. K. Kerrigan C. Chemistry with Calculators (continued) D. Spectrum of Activities (continued) E. Science Education for Public Understanding (SEPUP) and Chemistry, Health, Environment, and Me, M. Koker and L. Akin (2 hours) 10:30 a.m.-11:30 a.m. A. Increasing Aptitude and Interest of High School Students through Summer Camp, C. E. Fulton, and Energy Teaching Introduction to High School Chemistry, L.-M. Trejo B. Chemistry in Science Museum Exhibits: Opportunities and Challenges and Cooking with Chemistry, D. Katz C. Chemistry with Calculators (continued) D. Spectrum of Activities (continued) E. SEPUP (continued) 12:00 noon-1:15 p.m., High School Luncheon Educating High School Teachers for the 21st Century, Glenn Crosby
Hundred metre virtual telescope captures unique detailed colour image
NASA Astrophysics Data System (ADS)
2009-02-01
A team of French astronomers has captured one of the sharpest colour images ever made. They observed the star T Leporis, which appears, on the sky, as small as a two-storey house on the Moon [1]. The image was taken with ESO's Very Large Telescope Interferometer (VLTI), emulating a virtual telescope about 100 metres across and reveals a spherical molecular shell around an aged star. ESO PR Photo 06a/09 The star T Leporis as seen with VLTI ESO PR Photo 06b/09 The star T Leporis to scale ESO PR Photo 06c/09 A virtual 100-metre telescope ESO PR Photo 06d/09 The orbit of Theta1 Orionis C ESO PR Video 06a/09 Zoom-in onto T Leporis "This is one of the first images made using near-infrared interferometry," says lead author Jean-Baptiste Le Bouquin. Interferometry is a technique that combines the light from several telescopes, resulting in a vision as sharp as that of a giant telescope with a diameter equal to the largest separation between the telescopes used. Achieving this requires the VLTI system components to be positioned to an accuracy of a fraction of a micrometre over about 100 metres and maintained so throughout the observations -- a formidable technical challenge. When doing interferometry, astronomers must often content themselves with fringes, the characteristic pattern of dark and bright lines produced when two beams of light combine, from which they can model the physical properties of the object studied. But, if an object is observed on several runs with different combinations and configurations of telescopes, it is possible to put these results together to reconstruct an image of the object. This is what has now been done with ESO's VLTI, using the 1.8-metre Auxiliary Telescopes. "We were able to construct an amazing image, and reveal the onion-like structure of the atmosphere of a giant star at a late stage of its life for the first time," says Antoine Mérand, member of the team. "Numerical models and indirect data have allowed us to imagine the appearance of the star before, but it is quite astounding that we can now see it, and in colour." Although it is only 15 by 15 pixel across, the reconstructed image shows an extreme close-up of a star 100 times larger than the Sun, a diameter corresponding roughly to the distance between the Earth and the Sun. This star is, in turn, surrounded by a sphere of molecular gas, which is about three times as large again. T Leporis, in the constellation of Lepus (the Hare), is located 500 light-years away. It belongs to the family of Mira stars, well known to amateur astronomers. These are giant variable stars that have almost extinguished their nuclear fuel and are losing mass. They are nearing the end of their lives as stars, and will soon die, becoming white dwarfs. The Sun will become a Mira star in a few billion years, engulfing the Earth in the dust and gas expelled in its final throes. Mira stars are among the biggest factories of molecules and dust in the Universe, and T Leporis is no exception. It pulsates with a period of 380 days and loses the equivalent of the Earth's mass every year. Since the molecules and dust are formed in the layers of atmosphere surrounding the central star, astronomers would like to be able to see these layers. But this is no easy task, given that the stars themselves are so far away -- despite their huge intrinsic size, their apparent radius on the sky can be just half a millionth that of the Sun. "T Leporis looks so small from the Earth that only an interferometric facility, such as the VLTI at Paranal, can take an image of it. VLTI can resolve stars 15 times smaller than those resolved by the Hubble Space Telescope," says Le Bouquin. To create this image with the VLTI astronomers had to observe the star for several consecutive nights, using all the four movable 1.8-metre VLT Auxiliary Telescopes (ATs). The ATs were combined in different groups of three, and were also moved to different positions, creating more new interferometric configurations, so that astronomers could emulate a virtual telescope approximately 100 metres across and build up an image. "Obtaining images like these was one of the main motivations for building the Very Large Telescope Interferometer. We have now truly entered the era of stellar imaging," says Mérand. A perfect illustration of this is another VLTI image showing the double star system Theta1 Orionis C in the Orion Nebula Trapezium. This image, which was the first ever constructed from VLTI data, separates clearly the two young, massive stars from this system. The observations themselves have a spatial resolution of about 2 milli-arcseconds. From these, and several other observations, the team of astronomers, led by Stefan Kraus and Gerd Weigelt from the Max-Planck Institute in Bonn, could derive the properties of the orbit of this binary system, including the total mass of the two stars (47 solar masses) and their distance from us (1350 light-years).
VizieR Online Data Catalog: i filter photometry for HATS-25 through HATS-30 (Espinoza+, 2016)
NASA Astrophysics Data System (ADS)
Espinoza, N.; Bayliss, D.; Hartman, J. D.; Bakos, G. A.; Jordan, A.; Zhou, G.; Mancini, L.; Brahm, R.; Ciceri, S.; Bhatti, W.; Csubry, Z.; Rabus, M.; Penev, K.; Bento, J.; de Val-Borro, M.; Henning, T.; Schmidt, B.; Suc, V.; Wright, D. J.; Tinney, C. G.; Tan, T. G.; Noyes, R.
2017-05-01
The photometric detection data of the six exoplanets come from the three HATSouth sites, namely, the site at Las Campanas Observatory in Chile (LCO, whose stations are designated HS-1 and HS-2), the site at of the High Energy Spectroscopic Survey (HESS) in Namibia (whose stations are designated HS-3 and HS-4) and the site at the Siding Spring Observatory (SSO) in Australia whose stations are designated HS-5 and HS-6). HATS-25 was observed with an r SDSS filter on 2011 Mar-2011 Aug using HS-2.1, on 2011 Jul-2011 Aug using HS-4.1, and on 2011 May with HS-6.1. HATS-26 was observed with an r SDSS filter on 2012 Feb-2012 Jun using HS-2.3, HS-4.3, and HS-6.3. HATS-27 was observed with an r SDSS filter on 2011 Apr-2012 Jul using HS-2.1, on 2011 Jul-2012 Jul using HS-4.1, and on 2011 May-2012 Jul using HS-6.1. HATS-28 was observed with an r SDSS filter on 2013 Mar-2013 Oct using HS-1.2, on 2013 Sep-2013 Oct using HS-2.2, on 2013 Apr-2013 Nov using HS-3.2, on 2013 Sep-2013 Nov using HS-4.2 and HS-6.2, and 2013 Mar-2013 Nov using HS-5.2. HATS-29 was observed with an r SDSS filter on 2013 Apr-2013 May using HS-1.1, on 2013 Sep-2013 Oct using HS-2.1, on 2013 Apr-2013 Nov using HS-3.1, on 2013 Sep-2013 Nov using HS-4.1 and HS-6.1, and on 2013 Mar-2013 Nov using HS-5.1. HATS-30 was observed using an r SDSS filter on 2012 Sep-2012 Dec using HS-2.3, HS-6.3 and HS-2.4, on 2012 Sep-2013 Jan using HS-4.4, on 2012 Sep-2012 Dec using HS-6.4, and on 2011 Jul-2012 Oct using HS-1.1, HS-3.1 and HS-5.1. Photometric follow-up for the six systems was obtained mainly from 1m-class telescopes at different sites of the Las Cumbres Observatory Global Telescope (LCOGT) network, using the i filter. In particular, one partial transit and a full transit was observed for HATS-25b on 2015 February 23 at Cerro Tololo Inter-American Observatory (CTIO) and 2015 March 16 at SSO, respectively; three partial transits were observed for HATS-26b on 2015 April 19 and 2015 May 21 at CTIO, and 2015 June 04 at SSO; one full transit was observed for HATS-27b on 2015 April 09 at SSO; two partial transits were observed for HATS-28b on 2015 August 31 and 2015 September 03 at CTIO; one full transit and a partial transit were observed for HATS-29b on 2015 and 2014 June, respectively, at CTIO; and two partial transits were observed for HATS-30b on 2014 October 19 at South African Astronomical Observatory (SAAO) and on 2014 Oct 23 at CTIO. In addition, one full transit of HATS-27b was observed using the 0.3m Perth Exoplanet Survey Telescope (PEST) on 2015 March 12 using a RC filter. The reconnaissance spectroscopy of our candidates was made using the Wide Field Spectrograph (WiFeS), located on the Australian National University (ANU) 2.3m telescope. The observing strategy usually consists of taking data with two resolutions: R=λ/Δλ=7000 (medium) and R=3000 (low). For HATS-25, four medium resolution spectra (2014 Jun-Aug) and one low resolution spectrum (2014 Aug 5) were obtained. For HATS-26, two medium resolution spectra (2014 Jun 3-5) and one low resolution spectrum (2014 Jun 4) were obtained. For HATS-27, three medium resolution (2014 Jun 3-5) and one low resolution (2014 Jun 2) spectra were obtained. For HATS-28, only one low resolution spectrum (2015 Jun 1) was obtained. For HATS-29, four medium resolution spectra (2014 Dec-2015 Mar) and one low resolution spectrum (2015 Mar 2) were obtained. For HATS-30, three medium resolution spectra (2014 Oct 4-10) and one low resolution spectrum (2014 Oct 4) were obtained. High-precision spectroscopy was obtained for our targets with different instruments. Several R=115000 spectra were taken with the High Accuracy Radial Velocity Planet Searcher (HARPS) on the ESO 3.6m telescope at La Silla Observatory (LSO) between 2015 February and 2016 March in order to obtain high-precision radial velocities for HATS-25, HATS-26, HATS-27, and HATS-29. Spectra with R=48000 were also taken with the Fiber-fed Extended Range Optical Spectrograph (FEROS) mounted on the Max Planck Gesellschaft (MPG) 2.2m telescope at La Silla Observatory (LSO) between 2014 July and 2015 July in order to both extract precise spectroscopic parameters of the host stars and obtain precise radial velocities for all of our targets. In addition, R=60000 spectra were also taken with the CORALIE spectrograph mounted on the 1.2m Euler telescope at LSO between 2014 June and November for HATS-26, HATS-27, HATS-29, and HATS-30. Finally, eight R=70000 spectra were obtained for HATS-29 on 2015 May to measure radial velocities, using the CYCLOPS2 fiber feed with the University College London Echelle Spectrograph (UCLES) on the 3.9m Anglo-Australian Telescope (AAT). (3 data files).
VizieR Online Data Catalog: Photometry for HATS-31 through HATS-35 (de Val-Borro+, 2016)
NASA Astrophysics Data System (ADS)
de Val-Borro, M.; Bakos, G. A.; Brahm, R.; Hartman, J. D.; Espinoza, N.; Penev, K.; Ciceri, S.; Jordan, A.; Bhatti, W.; Csubry, Z.; Bayliss, D.; Bento, J.; Zhou, G.; Rabus, M.; Mancini, L.; Henning, T.; Schmidt, B.; Tan, T. G.; Tinney, C. G.; Wright, D. J.; Kedziora-Chudczer, L.; Bailey, J.; Suc, V.; Durkan, S.; Lazar, J.; Papp, I.; Sari, P.
2017-05-01
The HATSouth survey is a global network of homogeneous, completely automated wide-field telescopes located at three sites in the Southern Hemisphere: HS-1 and -2 are located at Las Campanas Observatory (LCO) in Chile, HS-3 and -4 are located at the High Energy Stereoscopic Survey (H.E.S.S.) site in Namibia, and HS-5 and -6 are located at Siding Spring Observatory (SSO) in Australia. Observations are performed using a Sloan-r filter with four-minute exposures. The HATSouth network was commissioned in 2009 and since then has proved to be a robust system for the monitoring of time-variable phenomena. Each HATSouth unit consists of four Takahashi E180 astrographs with an aperture of 18cm and an f/2.8 focal ratio on a common mount, equipped with Apogee 4096*4096 U16M ALTA cameras. HATS-31 was observed with the HS-1.4/G565 on 2012 Dec-2013 Jun, with the HS-3.4/G565 on 2012 Dec-2013 Jul, and with the HS-5.4/G565 on 2012 Dec-2013 Jul. HATS-32 was observed with the HS-2.3/G586 on 2010 Aug-2011 Nov, with the HS-4.3/G586 on 2010 Aug-2011 Nov, and with the HS-6.3/G586 on 2010 Aug-2011 Nov. HATS-33 was observed with the HS-1.4/G747 on 2013 Mar-2013 Oct, with the HS-2.4/G747 on 2013 Sep-2013 Oct, with the HS-3.4/G747 on 2013 Apr-2013 Nov, with the HS-4.4/G747 on 2013 Sep-2013 Nov, with the HS-5.4/G747 on 2013 Mar-2013 Nov, and with the HS-6.4/G747 on 2013 Sep-2013 Nov. HATS-34 was observed with the HS-2.4/G754 on 2012 Sep-2012 Dec, with the HS-4.4/G754 on 2012 Sep-2013 Jan, and with the HS-6.4/G754 on 2012 Sep-2012 Dec. HATS-35 was observed with the HS-2.4/G778 on 2011 May-2012 Nov, with the HS-4.4/G778 on 2011 Jul-2012 Nov, with the HS-6.4/G778 on 2011 Apr-2012 Oct. The egress of HATS-31b was observed on 2015 February 28 and 2015 April 02 with the Las Cumbres Observatory Global Telescope (LCOGT) 1m+Cerro Tololo Inter-American Observatory (CTIO) telescope network and the Swope 1m telescopes, respectively. Additionally, an almost full transit of HATS-31b was observed with LCOGT 1m+South African Astronomical Observatory/Santa Barbara Instrument Group (LCOGT 1 m+SAAO/SBIG) on 2015 March 6. Another three partial transits of HATS-32b were observed with the Perth Exoplanet Survey Telescope (PEST) 0.3m, DK 1.54m, and the Swope 1m telescopes on 2014 Jul 09, 2014 Nov 04, and 2015 May 28, respectively. The egress of HATS-33 was measured with the 1m LCOGT at CTIO on 2015 May 20. Both ingress and egress of HATS-34b were observed by the PEST 0.3m on 2014 Oct 26 and by the Danish Faint Object Spectrograph and Camera (DFOSC) on the DK 1.54m telescope on 2014 Nov 03. HATS-34b was also observed using Anglo-Australian Telescope 3.9m/InfraRed Imaging Spectrograph 2 (AAT 3.9m/IRIS2) on 2015 Sep 25 but This light curve covers a predicted secondary eclipse event, it is not included in the analysis carried out to determine the system parameters for HATS-34 (however, it is included in the analysis carried out to exclude blend scenarios). Finally, five partial transit events of HATS-35b were obtained between 2015 June 12 and 2015 July 24 using the LCOGT network at CTIO on 2015 Jun 12, 2015 Jul 15 and 2015 Jul 24, at SAAO on 2015 Jul 14, and at SSO on 2015 Jul 18. Reconnaissance spectroscopy was carried out using the Wide Field Spectrograph (WiFeS) on the Australian National University (ANU) 2.3m telescope at SSO on 2014 Dec 30-31 and 2015 Jan 1 for HATS-31, on 2014 Jun 3-5 and 2014 Jun 4 for HATS-32, on 2014 Dec-2015 Mar and 2015 Mar 4 for HATS-33, on 2014 Oct 4 and 2014 Oct 4-10 for HATS-34, and on 2014 Oct 5 and 2014 Oct 11 for HATS-35. Medium-resolution WiFeS observations spectral resolution was R=λ/Δλ=7000. We obtained 11 spectra using CYCLOPS2+University College London Echelle Spectrograph (CYCLOPS2+UCLES; Δλ/λ/1000=70) at the 3.9m AAT on 2015 May 7-13 for HATS-33, 11 spectra using the High-Accuracy Radial velocity Planetary Searcher (HARPS; Δλ/λ/1000=115) on the European Southern Observatory (ESO) 3.6m telescope (6 spectra on 2015 Feb 14-19 for HATS-31; 3 spectra on 2015 Apr 6-8 for HATS-33; 2 spectra on 2015 Apr 7-8 for HATS-35), 10 spectra using CORALIE (Δλ/λ/1000=60) on the Euler 1.2m telescope (5 spectra on 2015 Mar-Jun for HATS-33; 5 spectra on 2014 Nov-2015 Jun for HATS-35), and 32 spectra with Fiber-fed Extended Range Optical Spectrograph (FEROS; Δλ/λ/1000=48) at the Max Planck Gesellschaft (MPG) 2.2m telescope (8 spectra on 2014 Jul-2015 Jun for HATS-32; 4 spectra on 2015 May-Jul for HATS-33; 10 spectra on 2015 Jun-Jul for HATS-34; 10 spectra on 2015 Jun-Jul for HATS-35). The photometric data are available in Table3. The high-resolution spectroscopic data are provided in Table8. (3 data files).
NASA Astrophysics Data System (ADS)
Tuccari, G.; Bezrukovs, Vl.; Nechaeva, M.
2012-12-01
A digital base band converter (DBBC) system has been developed by the Istituto di Radioastronomia (Noto, Italy) for increasing the sensitivity of European VLBI Network (EVN) by expanding the full observed bandwidth using numerical methods. The output data rate of this VLBI-backend is raised from 1 to 4 Gbps for each radiotelescope. All operations related to the signal processing (frequency translation, amplification, frequency generation with local oscillators, etc.) are transferred to the digital domain, which allows - in addition to well-known advantages coming from digital technologies - achieving better repeatability, precision, simplicity, etc. The maximum input band of DBBC system is 3.5 GHz, and the instantaneous bandwidth is up to 1 GHz for each radio frequency/intermediate frequency (RF/IF) out of the eight possible. This backend is a highly powerful platform for other radioastronomy applications, and a number of additional so-called personalities have been developed and used. This includes PFB (polyphase filter bank) receivers and Spectra for high resolution spectroscopy. An additional new development with the same aim - to use the DBBC system as a multi-purpose backend - is related to the bi-static radar observations including Radar VLBI. In such observations it is possible to study the population of space debris, with detection of even centimetre class fragments. A powerful transmitter is used to illuminate the sky region to be analyzed, and the echoes coming from known or unknown objects are reflected to one or more groundbased telescopes thus producing a single-dish or interferometric detection. The DBBC Radar VLBI personality is able to realize a high-resolution spectrum analysis, maintaining in the central area the echo signal at the expected frequency including the Doppler shift of frequency. For extremely weak signals a very large integration time is needed, so for this personality different input parameters are provided. The realtime information can then allow exploring easily the desired range of search for unknown or not fully determined orbit objects. These features make Radar VLBI personality most useful in the space debris measurements. DBBC sistēma izstrādāta Noto Radioastronomijas institūtā. Sistēmas galvenais
Invasive cancer cells and metastasis
NASA Astrophysics Data System (ADS)
Mierke, Claudia Tanja
2013-12-01
The physics of cancer is a relatively new emerging field of cancer research. In the last decade it has become a focus of biophysical research as well as becoming a novel focus for classical cancer research. This special section of Physical Biology focusing on invasive cancer cells and metastasis (physical oncology) will give greater insight into the different subfields where physical approaches are being applied to cancer research. This focus on the physical aspects of cancer is necessary because novel approaches in the field of genomics and proteomics have not altered the field of cancer research dramatically, due to the fact that few breakthroughs have been made. It is still not understood why some primary tumors metastasize and thus have a worse outcome compared to others that do not metastasize. As biophysicists, we and others suggest that the mechanical properties of the cancer cells, which possess the ability to transmigrate, are quite different compared to non-metastatic and non-invasive cancer cells. Furthermore, we hypothesize that these cancer cells undergo a selection process within the primary tumor that enables them to weaken their cell-cell adhesions and to alter their cell-matrix adhesions in order to be able to cross the outermost boundary of the primary tumor, as well as the surrounding basement membrane, and to invade the connective tissue. This prerequisite may also help the cancer cells to enter blood or lymph vessels, get transported with the vessel flow and form secondary tumors either within the vessel, directly on the endothelium, or in a different organ after crossing the endothelial lining a second time. This special section begins with a paper by Mark F Coughlin and Jeffrey J Fredberg on the changes in cytoskeletal dynamics and nonlinear rheology due to the metastatic capability of cancer cells from different cancer tissue types such as skin, bladder, prostate and kidney [1]. The hypothesis was that the metastatic outcome is impacted by the biophysical state of the primary tumor cell. To determine the cytoskeletal dynamics they chose magnetic twisting cytometry, where the spontaneous motion of surface bound marker beads was measured, which is a measure for the cytoskeletal remodeling dynamics. The group of Katarina Wolf measured the stiffness of the cell nucleus because it is the largest and stiffest organelle, which may hinder the migration of invasive tumor cells through dense connective tissue [2]. They combined atomic force confocal microscopy for measurement of bulk nuclear stiffness (the inverse of the compressibility) with simultaneous visualization of the cantilever-nucleus contact as well as monitoring of the cell's fate. The dynamics of tissue topology such as the mixing of compartments during cancer invasion and metastasis were theoretically analyzed by Lance L Munn [3]. In particular, he presented a mathematical model of tissue repair and tumor growth based on collective cell migration that simulates a wide range of tumor behaviors using correct tissue compartmentalization and connectivity. In the future, the topological analysis could be helpful for tumor diagnosis or monitoring tumor therapy. The group of Cynthia A Reinhart-King analyzed how the topological guidance of a 3D tumor cell migration at an interface of collagen densities affects cell motility [4]. In particular, they mimicked the heterogeneities in density of the tumor stroma by preparing gels with an interface of high and low density collagen gels and investigated how this affects cell motility. The author's review paper details the effect of focal adhesion proteins such as focal adhesion kinase (FAK) on cell motility and how this effect is driven by mechanical alterations of cells expressing FAK compared to cells with FAK knock-out [5]. In particular, it focused on mechanical properties regulated by FAK in comparison to the mechano-regulating protein vinculin. This article highlights that both focal adhesion proteins, vinculin and FAK synergize their functions to regulate the mechanical properties of cells such as stiffness and contractile forces. Finally, the knowledge of the mechanical properties of invasive and non-invasive cells could provide a source for future drug developments to inhibit formation of metastases. This special section also includes two papers from the group of Martin Herrmann, a research paper and a review paper. The research paper by Janko et al deals with the cooperative binding of Annexin A5 to phosphatidylserines on apoptotic cell membranes [6]. This could not alone serve as an 'eat me' signal for macrophages as healthy cells also express Annexin A5 on their cell surface. The authors suggest that the cooperative binding is altered and subsequently the fluidity of Annexin A5 on the membrane. Together this may serve as a signal for phagocytic cells to eat apoptotic cells and leave healthy ones untouched. The paper by Biermann et al reviews the role of biophysical signals in the clearance of apoptotic cells [7]. In addition to the acto-myosin cytoskeleton, the keratin network seems to play a role in cancer research. The paper from the Beil and the Marti group demonstrates that microrheology is a valuable tool to determine the viscoelastic properties of polymer networks such as the keratin network in cells and an arbitrary in vitro network [8]. They describe how the topology of the keratin network affects the overall mechanical behavior of cells. It seems that the field of physical oncology will continue to grow in the future and more research will address the mechanical properties of cancer cells and whole tissues. Biophysical methods will need to be further improved and adapted to the needs of cancer research. References [1] Coughlin M F and Fredberg J J 2013 Phys. Biol. 10 065001 [2] Krause M, te Riet J and Wolf K 2013 Phys. Biol. 10 065002 [3] Munn L L 2013 Phys. Biol. 10 065003 [4] Bordeleau F, Tang L N and Reinhart-King C A 2013 Phys. Biol. 10 065004 [5] Mierke C T 2013 Phys. Biol. 10 065005 [6] Janko C, Jeremic I, Biermann M, Chaurio R, Schorn C, Muñoz L E and Herrmann M 2013 Phys. Biol. 10 065006 [7] Biermann M, Maueröder C, Brauner J M, Chaurio R, Janko C, Herrmann M and Muñoz L E 2013 Phys. Biol. 10 065007 [8] Paust T, Paschke S, Beil M and Marti O 2013 Phys. Biol. 10 065008
EDITORIAL: Focus on Molecular Electronics FOCUS ON MOLECULAR ELECTRONICS
NASA Astrophysics Data System (ADS)
Scheer, Elke; Reineker, Peter
2008-06-01
The notion 'molecular electronics' has been used more frequently since the 1970s and summarizes a series of physical phenomena and ideas for their application in connection with organic molecules, oligomers, polymers, organic aggregates and solids. The properties studied in this field were connected to optical and electrical phenomena, such as optical absorption, fluorescence, nonlinear optics, energy transport, charge transfer, electrical conductance, and electron and nuclear spin-resonance. The final goal was and is to build devices which can compete or surpass some aspects of inorganic semiconductor devices. For example, on the basis of organic molecules there exist rectifiers, transistors, molecular wires, organic light emitting diodes, elements for photovoltaics, and displays. With respect to applications, one aspect of the organic materials is their broad variability and the lower effort and costs for their processability. The step from microstructures to the investigation of nanostructures is a big challenge also in this field and has lead to what nowadays is called molecular electronics in its narrow sense. In this field the subjects of the studies are often single molecules, e.g. single molecule optical spectroscopy, electrical conductance, i.e. charge transport through a single molecule, the influence of vibrational degrees of freedom, etc. A challenge here is to provide the techniques for addressing in a reproducible way the molecular scale. In another approach small molecular ensembles are studied in order to avoid artefacts from particular contact situations. The recent development of the field is presented in [1-8]. In this Focus Issue we present new results in the field of 'molecular electronics', both in its broad and specialized sense. One of the basic questions is the distribution of the energy levels responsible for optical absorption on the one hand and for the transport of charge on the other. A still unanswered question is whether the Wannier exciton model applies in which the excitation is distributed over several molecules or whether a good description is given by the Frenkel exciton model with the electron and the whole being localized at the same molecular unit. In organic semiconductors the charge transport usually occurs on the basis of holes because of the presence of many defects giving rise to a localization of the electrons. It is therefore a challenge to produce materials with both positive and negative mobile charge carriers. In the 1990s V M Agranovich introduced the idea of hybrid excitons, i.e. of nanostructured materials consisting of both organic and inorganic semiconductors. At the interface between the organic and inorganic parts new excitons can appear, being a superposition of both Frenkel and Wannier excitons and having both the high oscillator strength of the Frenkel and the large optical nonlinearity of the Wannier exciton. The problem is to find optimum combinations of the organic and inorganic parts to enable the hybrid structure concept to work. Micro-cavities also play an important role in the investigation of organic materials resulting in a new state (polariton) as the superposition of a photon and an exciton because of the large exciton-photon interaction. A similar excitation arises because of the interaction between plasmons and photons. A special geometrical shape of a nano-cavity increases the interaction between the electromagnetic radiation and a dipole sitting in the cavity. The interaction between vibronic degrees of freedom and electronic excitations plays an important role for various phenomena such as nonlinear processes, the question of coherence, information on the shape of a potential hypersurface, etc. With the help of femtosecond laser pulses, detailed information on such vibrations can be obtained. Also of great importance is the investigation of the energy transfer in artificial light-harvesting systems, e.g. in dendrimers. Finally the combination of experimental and theoretical investigations allows for a comparison of the spectra of two molecules with the same backbone (tetracene and rubrene). The transport of charge through a molecule occurs possibly in a stationary, but at any rate in a non-equilibrium situation. The study of dissipation in such situations requires special approaches, both in theory and in experiments. One key issue is the understanding of the role of the microscopic phenomena such as the excitation of vibrational modes and their macroscopic outcome, i.e. the dissipation. This topic is addressed in several contributions both theoretically and experimentally. From the theoretical side, for the investigation of the heat production during the electron transfer, non-equilibrium Green's functions have been utilized. In another contribution a combination of the non-equilibrium Green's function technique together with the density functional method has been developed for the calculation of the elastic and inelastic electronic transport. To calculate the transport of indistinguishable particles a path integral Monte Carlo approach has been put forward. In single-molecule transistors the gate-voltage dependence on the Kondo temperature and an accompanying strong Coulomb blockade can be explained by taking into account a strong electron-vibron interaction including anharmonicities of the molecular potential surface. The transport of charges is heavily influenced by disorder. The case of static disorder is investigated for linear chains, carbon nanotubes and graphene ribbons. Finally it is shown that the charge transport through a single energy level coupled to a localized vibrational mode and two leads shows hysteretic effects which could possibly be used in a memory device. For applications the control of the current through a molecular junction is considered theoretically. Two possible mechanisms are discussed: the control via coherent destruction using predefined ultrafast laser pulses and the formation of laser pulses using optimal control theory. A group of contributions is dedicated to the study of electronic transport through molecules using various techniques ranging from scanning-tunnelling methods via controllable break-junctions to printing techniques and molecular networks. The molecules under study can be classified into two main groups. On the one hand the functionalization of aromatic or alkane molecules with thiols is used for establishing chemical binding to metal electrodes; in the other set of experiments fullerenes are used as model systems for studying the influence of orientation and heat dissipation. Molecular conducting networks are important under various aspects. Such networks are formed by an array of gold nanoparticles connected by conjugated molecular chains with one or two thiol ends and conduction investigations are performed under various conditions. A careful investigation of the experimental conditions is necessary when comparing conductance measurements using the break junction method. For example there are results demonstrating that several molecular junctions are formed in parallel between the electrodes. Other experiments use different materials for the junctions and measurements are performed at various temperatures. The transport of charge through an alkane-monolayer is investigated using micro-transfer printing to establish contacts without shorts. It is shown that both tunnelling between the electrodes and transport through the states of the molecules contribute to the conductance. C60 plays a role in various fields of molecular electronics. One aspect is the conductance through the molecule as a function of the orientation of the molecule on the surface. It is found that there is a strong orientation dependence of the transport on Au(111) surfaces and that it is almost independent on a Cu(100) surface. A further important phenomenon is the heating and cooling of C60 during charge transport depending on the surface of C60 adsorption. The differences are ascribed to the amount of charge transfer into C60 upon adsorption on different surfaces. In summary, in the field of molecular electronics new materials and structures are developed and investigated, both with respect to a basic understanding of the materials and their compositions and with respect to possible applications in electronics. While in the field of molecular electronics on the microscale the techniques are well established, they still need to be refined in the field of nano-molecular electronics. Nevertheless, both subfields share some of the most challenging questions: e.g. the problems of charge and energy transport, of excitations and the formation of new quasi-particles. Another question is the role of vibrational degrees of freedom, where on the one hand one has to cope with the unavoidable effect of heat dissipation. On the other hand, vibrational excitations are intimately connected to the individual molecule under study and thus offer the possibility to be used in functional devices based on intrinsic molecular properties. This Focus Issue represents a snapshot of the state of the art of this emerging field in the first half of 2008. We expect that the fast development which the research has undergone in recent years will even speed up in the near future. References [1] Pope M and Sweenberg Ch E 1999 Electronic Processes in Organic Crystals and Polymers 2nd edn (Oxford: Oxford University Press) [2] Silinsh E A and Capek V 1994 Organic Molecular Crystals (New York: AIP Press) [3] Agranovich V M and La Rocca G C 2002 Organic Nanostructures: Science and Applications, Proc. Int. School of Physics 'Enrico Fermi', Course CXLIX (Amsterdam: IOS Press) [4] Schwoerer M and Wolf H C 2007 Organic Molecular Solids (Weinheim: Wiley-VCH) [5] Cuniberti G, Fagas G and Richter K (ed) 2005 Introducing Molecular Electronics, Lecture Notes in Physics (Berlin: Springer) [6] Reed M and Lee T 2003 Molecular Nanoelectronics (Stevenson Ranch, CA: American Scientific Publishers) [7] Petty M C 2007 Molecular Electronics, (Weinheim: Wiley-VCH) [8] 2006 Molecular Wires and Nanoscale Conductors Faraday Discuss. 131 1-420 Focus on Molecular Electronics Contents Model of mixed Frenkel and charge-transfer excitons in donor-acceptor molecular crystals: investigation of vibronic spectra I J Lalov, C Warns and P Reineker Suppressing the current through molecular wires: comparison of two mechanisms GuangQi Li, Michael Schreiber and Ulrich Kleinekathöfer Charge-memory effect in a polaron model: equation-of-motion method for Green functions Pino D'Amico, Dmitry A Ryndyk, Gianaurelio Cuniberti and Klaus Richter Determination of transport levels of organic semiconductors by UPS and IPS S Krause, M B Casu, A Schöll and E Umbach Electrical characterization of alkane monolayers using micro-transfer printing: tunneling and molecular transport C Kreuter, S Bächle, E Scheer and A Erbe Correlated charge transfer along molecular chains L Mühlbacher and J Ankerhold Non-equilibrium Green's functions in density functional tight binding: method and applications A Pecchia, G Penazzi, L Salvucci and A Di Carlo Asymmetric Coulomb blockade and Kondo temperature of single-molecule transistors Florian Elste and Felix von Oppen Electron-phonon scattering in molecular electronics: from inelastic electron tunnelling spectroscopy to heating effects Alessio Gagliardi, Giuseppe Romano, Alessandro Pecchia, Aldo Di Carlo, Thomas Frauenheim and Thomas A Niehaus Interlinking Au nanoparticles in 2D arrays via conjugated dithiolated molecules Jianhui Liao, Markus A Mangold, Sergio Grunder, Marcel Mayor, Christian Schönenberger and Michel Calame Conductance values of alkanedithiol molecular junctions M Teresa González, Jan Brunner, Roman Huber, Songmei Wu, Christian Schönenberger and Michel Calame Particularities of surface plasmon-exciton strong coupling with large Rabi splitting C Symonds, C Bonnand, J C Plenet, A Bréhier, R Parashkov, J S Lauret, E Deleporte and J Bellessa Excitonic and vibrational nonlinear processes in a polydiacetylene studied by a few-cycle pulse laser T Kobayashi, I Iwakura and A Yabushita Correlations of instantaneous transition energy and intensity of absorption peaks during molecular vibration: toward potential hyper-surface Takayoshi Kobayashi and Zhuan Wang Diffusion and localization in carbon nanotubes and graphene nanoribbons Norbert Nemec, Klaus Richter and Gianaurelio Cuniberti Molecular electronics in junctions with energy disorder Franz J Kaiser, Peter Hänggi and Sigmund Kohler Spatially resolved conductance of oriented C60 G Schull, N Néel, M Becker, J Kröger and R Berndt A design for an optical-nanocavity optimized for use with surface-bound light-emitting materials A M Adawi and D G Lidzey Electronic coupling of optical excitations in organic/inorganic semiconductor hybrid structures S Blumstengel, S Sadofev and F Henneberger The relation between the symmetry of vibrational modes and the potential curve displacement associated with electronic transition studied by using real-time vibrational spectroscopy Takayoshi Kobayashi, Zhuan Wang and Izumi Iwakura Lithographic mechanical break junctions for single-molecule measurements in vacuum: possibilities and limitations Christian A Martin, Dapeng Ding, Herre S J van der Zant and Jan M van Ruitenbeek Strong exciton-photon coupling at room temperature in microcavities containing two-dimensional layered perovskite compounds G Lanty, A Bréhier, R Parashkov, J S Lauret and E Deleporte Bipolar transport in organic field-effect transistors: organic semiconductor blends versus contact modification Andreas Opitz, Michael Kraus, Markus Bronner, Julia Wagner and Wolfgang Brütting Resonant heating and substrate-mediated cooling of a single C60 molecule in a tunnel junction Gunnar Schulze, Katharina J Franke and Jose Ignacio Pascual
PREFACE: Rutherford Centennial Conference on Nuclear Physics
NASA Astrophysics Data System (ADS)
Freeman, Sean
2012-09-01
Just over one hundred years ago, Ernest Rutherford presented an interpretation of alpha-particle scattering experiments, performed a couple of years earlier by Geiger and Marsden, to the Manchester Literary and Philosophical Society. The work was summarised shortly afterwards in a paper in the Philosophical Magazine. He postulated that a dense speck of matter must exist at the centre of an atom (later to become known as the nucleus) if the details of the experiments, particularly the yield of alpha particles scattered through large angles, were to be explained. The nuclear hypothesis, combined with the experimental work by Moseley on X-rays and Bohr's theoretical ideas, both also initiated at the Victoria University of Manchester, established our view of atomic structure and gave birth to the field of nuclear physics. The Rutherford Centennial Conference on Nuclear Physics was held at The University of Manchester in August 2011 to celebrate this anniversary by addressing the wide range of contemporary topics that characterise modern nuclear physics. This set of proceedings covers areas including nuclear structure and astrophysics, hadron structure and spectroscopy, fundamental interactions studied within the nucleus and results of relativistic heavy-ion collisions. We would like to thank all those who presented their recent research results at the conference; the proceedings stand as a testament to the excitement and interest that still pervades the pursuit of this field of physics. We would also like to thank those who contributed in other ways to the conference. To colleagues at the Manchester Museum of Science and Industry for putting together an exhibition to coincide with the conference that included the manuscript of the 1911 paper, letters, notebooks and equipment used by Rutherford. These items were kindly loaned by Cambridge and Manchester Universities. Winton Capital generously supported this exhibition. We would also like to thank Professor Mary Fowler, Rutherford's great-granddaughter, and Professor Stephen Watts, Head of the School of Physics and Astronomy at Manchester, for opening the exhibition as part of the welcome reception for the conference. The reception was only possible with support from Canberra Industries. We are grateful to His Excellency Mr Derek Leask, New Zealand High Commissioner to the United Kingdom, to Professor Rod Coombs, Deputy President of The University of Manchester, and to Professor David Phillips, the President of the Royal Society of Chemistry, for their contributions to the formal opening of the conference. Manchester City Council kindly supported a civic reception hosted by the Lord Mayor of the City of Manchester, Councillor Harry Lyons JP, at Manchester Town Hall. The Ogden Trust helped support the conference dinner and Professor George Dracoulis provided an entertaining after dinner speech. Thank you for these contributions to the social programme of the conference. In addition to the exhibition at the Museum, which was open to the public until October 2011, the conference programme also included a series of public evening lectures and we are grateful both to the speakers (David Jenkins, Alan Perkins and John Roberts) and to those providing support for the public engagement activities (the Institute of Physics Nuclear Physics Group, the Institute of Physics and Engineering in Medicine, the Nuclear Institute and the Science and Technology Facilities Council). We would also like to thank the European Physical Society for providing conference travel grants to a number of young scientists. I would like to take this opportunity to thank the other members of the UK Organising Committee for their help in making the conference a success and for their work in putting these proceedings together. In addition, the International Advisory Committee provided essential advice that contributed to the selection of the plenary speakers who were without exception engaging, interesting and entertaining, giving a really excellent set of presentations. Finally we are also pleased to express our thanks to the Conference Office of the Institute of Physics for their invaluable support in organising this event. We are especially grateful to Dawn Stewart for her responsive and efficient day-to-day handling of this event, as well as to Claire Garland for her planning and management of this event. This conference is the second in a series of conferences that began with the Rutherford Jubilee Conference held in Manchester in 1961, which is described in one of the contributions to these proceedings. I do hope that at least some of the delegates from the Centennial Conference will be able to attend the next one, fifty years hence in 2061, just as we were honoured to have some of the Jubilee delegates with us for the Centennial. If I am still around, I doubt that I will have the energy then to be conference chair. I would also not like to attempt to predict the plenary programme, but I hope that it will be as vibrant and exciting as the 2011 conference. Professor Sean J Freeman Conference Chair On behalf of the UK Organising Committee Ernest Rutherford Ernest Rutherford (Photograph courtesy of The University of Manchester) Edited by: Sean Freeman (The University of Manchester) Andrei Andreyev (University of the West of Scotland/The University of York) Alison Bruce (University of Brighton) Alick Deacon (The University of Manchester) Dave Jenkins (University of York) Dave Joss (University of Liverpool) Douglas MacGregor (University of Glasgow) Paddy Regan (University of Surrey) John Simpson (University of Daresbury) Garry Tungate (University of Birmingham) Bob Wadsworth (University of York) Dan Watts (University of Edinburgh) International Advisory Panel: A Aprahamian (Notre Dame, USA) J Äystö (Jyväskylä, Finland) F Aziaez (Orsay, France) J-P Blaizot (Saclay, France/ECT, Italy) A Bracco (Milan, Italy) H Caines (Yale, USA) C W de Jaeger (JLAB, USA) J Dilling (TRIUMF, Canada) J Dobacewski (Warsaw, Poland) G Dracoulis (ANU, Australia) S J Freedman (LBL, USA) M Hass (Weizmann Institute, Israel) M Huyse (Leuven, Belgium) P Jones (Birmingham, UK) D Khao (Hanoi, Vietnam) R Krücken (Munich, Germany) K Langanke (Darmstadt, Germany) C Lister (Argonne, USA) G A Miller (University of Washington, USA) D Morrissey (MSU, USA) T Motobayashi (RIKEN, Japan) S Nagamiya (J-PARC, Japan) W Nazarewicz (ORNL, USA) S Mullins (iThemba, South Africa) T Nakamura (Tokyo, Japan) P Roussel Chomaz (GANIL, France) R Ribas (Sao Paolo, Brazil) M Vanderhaeghen (Mainz, Germany) U Wiedner (Uppsala, Sweden) F Xu (Peking University, China) Q Zhao (IHEP, Bejing) W Zajc (Columbia, USA)
PREFACE: Dynamics of low-dimensional systems Dynamics of low-dimensional systems
NASA Astrophysics Data System (ADS)
Bernasconi, M.; Miret-Artés, S.; Toennies, J. P.
2012-03-01
With the development of techniques for high-resolution inelastic helium atom scattering (HAS), electron scattering (EELS) and neutron spin echo spectroscopy, it has become possible, within approximately the last thirty years, to measure the dispersion curves of surface phonons in insulators, semiconductors and metals. In recent years, the advent of new experimental techniques such as 3He spin-echo spectroscopy, scanning inelastic electron tunnel spectroscopy, inelastic x-ray scattering spectroscopy and inelastic photoemission have extended surface phonon spectroscopy to a variety of systems. These include ultra-thin metal films, adsorbates at surface and elementary processes where surface phonons play an important role. Other important directions have been actively pursued in the past decade: the dynamics of stepped surfaces and clusters grown on metal surfaces, due to their relevance in many dynamical and chemical processes at surfaces, including heterogeneous catalysis; clusters; diffusion etc. The role of surface effects in these processes has been conjectured since the early days of surface dynamics, although only now is the availability of ab initio approaches providing those conjectures with a microscopic basis. Last but not least, the investigation of non-adiabatic effects, originating for instance from the hybridization (avoided crossing) of the surface phonons branches with the quasi 1D electron-hole excitation branch, is also a challenging new direction. Furthermore, other elementary oscillations such as surface plasmons are being actively investigated. The aforementioned experimental breakthroughs have been accompanied by advances in the theoretical study of atom-surface interaction. In particular, in the past decade first principles calculations based on density functional perturbation theory have boosted the theoretical study of the dynamics of low-dimensional systems. Phonon dispersion relations of clean surfaces, the dynamics of adsorbates, and the vibrational spectra of clusters and carbon-based nanostructures, just to name a few of the low-dimensional systems addressed in this special issue, can be both accurately computed from first principles and measured experimentally. Even less computationally demanding semi-empirical simulations based on tight-binding or continuum models play a crucial role in assessing, for instance, the interplay between morphology, defects and the elastic properties of low-dimensional systems. The impressive amount of work and progress achieved in the past decade within the general theory and spectroscopy of the dynamics of low-dimensional systems is marked by several relevant trends that are exemplified by the contributions gathered together in this special issue. They span a wide spectrum of experimental and theoretical methods applied to the study of the dynamical properties of low-dimensional systems and new emerging phenomena at the nanoscale, such as the peculiar optical properties of ring shaped quantum dots, plasmon dynamics in metallic nanoclusters and the relaxation dynamics of nanomagnets. This issue is dedicated to our esteemed colleague Giorgio Benedek on the occasion of his 70th birthday. It collects together a number of papers written by authors from all over the world with a recognized reputation in the above mentioned fields where Giorgio Benedek has made important and fundamental contributions. Dynamics of low-dimensional systems contents Narratives Giorgio Benedek: an extraordinary universal scientist M Bernasconi, S Miret-Artés and J P Toennies Helium and carbon: two friends for life Giorgio Benedek Special Issue Papers Temperature dependence in atom-surface scattering Eli Pollak and J R Manson Density functional study of the decomposition pathways of SiH3 and GeH3 at the Si(100) and Ge(100) surfaces M Ceriotti, F Montalenti and M Bernasconi Comparative study of vibrations in submonolayer structures of potassium on Pt(111) G G Rusina, S V Eremeev, S D Borisova and E V Chulkov Surface phonons on Pb(111) I Yu Sklyadneva, R Heid, K-P Bohnen, P M Echenique and E V Chulkov Using evidence from nanocavities to assess the vibrational properties of external surfaces G F Cerofolini, F Corni, S Frabboni, G Ottaviani, E Romano, R Tonini and D Narducci Magnetic properties and relaxation dynamics of a frustrated Ni7 molecular nanomagnet E Garlatti, S Carretta, M Affronte, E C Sañudo, G Amoretti and P Santini A theoretical study of rotational and translational diffusion dynamics of molecules with a six-fold point symmetry adsorbed on a hexagonal lattice by neutron scattering I Calvo-Almazán, S Miret-Artés and P Fouquet Vibrational dynamics and surface structure of Bi(111) from helium atom scattering measurements M Mayrhofer-Reinhartshuber, A Tamtögl, P Kraus, K H Rieder and W E Ernst Double and triple ionization of silver clusters by electron impactAvik Halder, Anthony Liang, Chunrong Yin and Vitaly V Kresin Scattering of O2 from a graphite surface W W Hayes, Junepyo Oh, Takahiro Kondo, Keitaro Arakawa, Yoshihiko Saito, Junji Nakamura and J R Manson Zero-phonon lines of systems with different dimensions and unconventional vibronic interactions V Hizhnyakov A kinetic Monte Carlo approach to investigate antibiotic translocation through bacterial porins Matteo Ceccarelli, Attilio V Vargiu and Paolo Ruggerone Quantum Zeno and anti-Zeno effects in surface diffusion of interacting adsorbates H C Peñate-Rodrìguez, R Martìnez-Casado, G Rojas-Lorenzo, A S Sanz and S Miret-Artés Weakly bound finite systems: (4He)N-Rb2(3Σu), clustering structures from a quantum Monte Carlo approach D López-Durán, R Rodrìguez-Cantano, T González-Lezana, G Delgado-Barrio, P Villarreal, E Yurtsever and F A Gianturco Multiphonon atom-surface scattering from corrugated surfaces: derivation of the inelastic scattering spectrum for diffraction statesBranko Gumhalter Probing the non-pairwise interactions between CO molecules moving on a Cu(111) surfacePepijn R Kole, Holly Hedgeland, Andrew P Jardine, William Allison, John Ellis and Gil Alexandrowicz Fast emission dynamics in droplet epitaxy GaAs ring-disk nanostructures integrated on SiL Cavigli, S Bietti, M Abbarchi, C Somaschini, A Vinattieri, M Gurioli, A Fedorov, G Isella, E Grilli and S Sanguinetti Assessing the composition of hetero-epitaxial islands via morphological analysis: an analytical model matching GeSi/Si(001) dataR Gatti, F Pezzoli, F Boioli, F Montalenti and Leo Miglio Carbon sp chains in graphene nanoholesIvano E Castelli, Nicola Ferri, Giovanni Onida and Nicola Manini Elastic fields and moduli in defected grapheneRiccardo Dettori, Emiliano Cadelano and Luciano Colombo Tuning the plasmon energy of palladium-hydrogen systems by varying the hydrogen concentrationV M Silkin, R Dìez Muiño, I P Chernov, E V Chulkov and P M Echenique Plasmon tsunamis on metallic nanoclustersA A Lucas and M Sunjic Ab initio characterization of graphene nanoribbons and their polymer precursorsRengin Peköz, Xinliang Feng and Davide Donadio First-principles phonon calculations of Fe4+ impurity in SrTiO3E Blokhin, E A Kotomin and J Maier Phonon dispersion of quasi-freestanding graphene on Pt(111)Antonio Politano, Antonio Raimondo Marino and Gennaro Chiarello Vibrations of Au13 and FeAu12 nanoparticles and the limits of the Debye temperature conceptGhazal Shafai, Marisol Alcántara Ortigoza and Talat S Rahman Triple quantum dots as charge rectifiers M Busl and G Platero
NASA Astrophysics Data System (ADS)
2011-02-01
Using ESO's Very Large Telescope an international team of astronomers has been able to study the short-lived disc of material around a young star that is in the early stages of making a planetary system. For the first time a smaller companion could be detected that may be the cause of the large gap found in the disc. Future observations will determine whether this companion is a planet or a brown dwarf. Planets form from the discs of material around young stars, but the transition from dust disc to planetary system is rapid and few objects are caught during this phase [1]. One such object is T Chamaeleontis (T Cha), a faint star in the small southern constellation of Chamaeleon that is comparable to the Sun, but very near the beginning of its life [2]. T Cha lies about 350 light-years from the Earth and is only about seven million years old. Up to now no forming planets have been found in these transitional discs, although planets in more mature discs have been seen before (eso0842, heic0821). "Earlier studies had shown that T Cha was an excellent target for studying how planetary systems form," notes Johan Olofsson (Max Planck Institute for Astronomy, Heidelberg, Germany), one of the lead authors of two papers in the journal Astronomy & Astrophysics that describe the new work. "But this star is quite distant and the full power of the Very Large Telescope Interferometer (VLTI) was needed to resolve very fine details and see what is going on in the dust disc." The astronomers first observed T Cha using the AMBER instrument and the VLT Interferometer (VLTI) [3]. They found that some of the disc material formed a narrow dusty ring only about 20 million kilometres from the star. Beyond this inner disc, they found a region devoid of dust with the outer part of the disc stretching out into regions beyond about 1.1 billion kilometres from the star. Nuria Huélamo (Centro de Astrobiología, ESAC, Spain), the lead author of the second paper takes up the story: "For us the gap in the dust disc around T Cha was a smoking gun, and we asked ourselves: could we be witnessing a companion digging a gap inside its protoplanetary disc?" However, finding a faint companion so close to a bright star is a huge challenge and the team had to use the VLT instrument NACO in a novel and powerful way, called sparse aperture masking, to reach their goal [4]. After careful analysis they found the clear signature of an object located within the gap in the dust disc, about one billion kilometres from the star - slightly further out than Jupiter is within our Solar System and close to the outer edge of the gap. This is the first detection of an object much smaller than a star within a gap in the planet-forming dust disc around a young star. The evidence suggests that the companion object cannot be a normal star [5] but it could be either a brown dwarf [6] surrounded by dust or, most excitingly, a recently formed planet. Huélamo concludes: "This is a remarkable joint study that combines two different state-of-the-art instruments at ESO's Paranal Observatory. Future observations will allow us to find out more about the companion and the disc, and also understand what fuels the inner dusty disc." Notes [1] The transitional discs can be spotted because they give off less radiation at mid-infrared wavelengths. The clearing of the dust close to the star and the creation of gaps and holes can explain this missing radiation. Recently formed planets may have created these gaps, although there are also other possibilities. [2] T Cha is a T Tauri star, a very young star that is still contracting towards the main sequence. [3] The astronomers used the AMBER instrument (Astronomical Multi-BEam combineR) and the VLTI to combine the light from all four of the 8.2-metre VLT Unit Telescopes and create a "virtual telescope" 130 metres across. [4] NACO (or NAOS-CONICA in full) is an adaptive optics instrument attached to ESO's Very Large Telescope. Thanks to adaptive optics, astronomers can remove most of the blurring effect of the atmosphere and obtain very sharp images. The team used NACO in a novel way, called sparse aperture masking (SAM) to search for the companion. This is a type of interferometry that, rather than combining the light from multiple telescopes as the VLTI does, uses different parts of the mirror of a single telescope (in this case, the mirror of the VLT Unit Telescope 4). This new technique is particularly good for finding faint objects very close to bright ones. VLTI/AMBER is better suited to studying the structure of the inner disc and is less sensitive to the presence of a distant companion. [5] The astronomers searched for the companion using NACO in two different spectral bands - at around 2.2 microns and at 3.8 microns. The companion is only seen at the longer wavelength, which means that the object is either cool, like a planet, or a dust-shrouded brown dwarf. [6] Brown dwarfs are objects between stars and planets in size. They are not massive enough to fuse hydrogen in their cores but are larger than giant planets such as Jupiter. More information This research was presented in two papers: Olofsson et al. 2011, "Warm dust resolved in the cold disk around TCha with VLTI/AMBER", and Huélamo et al. 2011, "A companion candidate in the gap of the T Cha transitional disk", to appear in the journal Astronomy & Astrophysics. The team is composed of J. Olofsson (Max-Planck-Institut für Astronomie [MPIA], Heidelberg, Germany), M. Benisty (MPIA), J.-C. Augereau (Institut de Planétologie et d'Astrophysique de Grenoble [IPAG], France) C. Pinte (IPAG), F. Ménard (IPAG), E. Tatulli (IPAG), J.-P. Berger (ESO, Santiago, Chile), F. Malbet (IPAG), B. Merín (Herschel Science Centre, Madrid, Spain), E. F. van Dishoeck (Leiden University, Holland), S. Lacour (Observatoire de Paris, France), K. M. Pontoppidan (California Institute of Technology, USA), J.-L. Monin (IPAG), J. M. Brown (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), G. A. Blake (California Institute of Technology), N. Huélamo (Centro de Astrobiología, ESAC, Spain), P. Tuthill (University of Sydney, Australia), M. Ireland (University of Sydney), A. Kraus (University of Hawaii) and G. Chauvin (Université Joseph Fourier, Grenoble, France). 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 15 countries: Austria, Belgium, Brazil, 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".
VizieR Online Data Catalog: Kepler follow-up observation program. I. Imaging (Furlan+, 2017)
NASA Astrophysics Data System (ADS)
Furlan, E.; Ciardi, D. R.; Everett, M. E.; Saylors, M.; Teske, J. K.; Horch, E. P.; Howell, S. B.; van Belle, G. T.; Hirsch, L. A.; Gautier, T. N.; Adams, E. R.; Barrado, D.; Cartier, K. M. S.; Dressing, C. D.; Dupree, A. K.; Gilliland, R. L.; Lillo-Box, J.; Lucas, P. W.; Wang, J.
2017-07-01
We present results from six years of follow-up imaging observations of KOI host stars, including work done by teams from the Kepler Community Follow-up Observation Program (CFOP; https://exofop.ipac.caltech.edu/cfop.php) and by other groups. Several observing facilities were used to obtain high-resolution images of KOI host stars. Table1 lists the various telescopes, instruments used, filter bandpasses, typical Point Spread Function (PSF) widths, number of targets observed, and main references for the published results. The four main observing techniques employed are adaptive optics (Keck, Palomar, Lick, MMT), speckle interferometry (Gemini North, WIYN, DCT), lucky imaging (Calar Alto), and imaging from space with HST. A total of 3557 KOI host stars were observed at 11 facilities with 9 different instruments, using filters from the optical to the near-infrared. In addition, 10 of these stars were also observed at the 8m Gemini North telescope by Ziegler et al. 2016 (AJ accepted, arXiv:1605.03584) using laser guide star adaptive optics. The largest number of KOI host stars (3320) were observed using Robo-AO at the Palomar 1.5m telescope (Baranec et al. 2014ApJ...790L...8B; Baranec et al. 2016, Cat. J/AJ/152/18; Law et al. 2014, Cat. J/ApJ/791/35; Ziegler et al. 2016, AJ accepted, arXiv:1605.03584). A total of 8332 observations were carried out from 2009 September to 2015 October covering 3557 stars. We carried out observations at the Keck, Palomar, and Lick Observatory using the facility adaptive optics systems and near-infrared cameras from 2009 to 2015. At Keck, we observed with the 10m Keck II telescope and Near-Infrared Camera, second generation (NIRC2). The pixel scale of NIRC2 was 0.01''/pixel, resulting in a field of view of about 10''*10''. We observed our targets in a narrow K-band filter, Brγ, which has a central wavelength of 2.1686μm. In most cases, when a companion was detected, we also observed the target in a narrow-band J filter, Jcont, which is centered at 1.2132μm. At Palomar, we used the 5m Hale telescope with the Palomar High Angular Resolution Observer (PHARO). We used the 0.025''/pixel scale, which yielded a field of view of about 25''*25''. As at Keck, we typically used a narrow-band filter in the K-band, Brγ centered at 2.18μm, to observe our targets. When a companion was detected, we usually also observed our targets in the J filter (centered at 1.246μm). At Lick, we used the 3m Shane telescope and the IR Camera for Adaptive Optics at Lick (IRCAL). With its 0.075''/pixel scale, it offered a field of view of about 19''*19''. We observed our targets with the J filter (centered at 1.238μm) or the H filter (centered at 1.656μm). Our team also carried out speckle imaging using the Differential Speckle Survey Instrument (DSSI) at Gemini North, the Wisconsin-Indiana-Yale-NOAO (WIYN) telescope, and at the Discovery Channel Telescope (DCT) from 2010 to 2015. Table5 lists the various observing dates at the three telescopes. At the 8m Gemini North telescope, 158 unique KOI host stars were observed, while at the 3.5m WIYN telescope, 681 stars were targeted. The more recent observing runs at the 4m DCT telescope covered 75 stars. Overall, at all three telescopes, the observations were directed at 828 unique KOI host stars. Targets were observed simultaneously in two bands, centered at 562nm and 692nm (both with a bandwidth of 40nm), or at 692nm and 880nm (the latter with a bandwidth of 50nm). Some targets have data in all three bands. The field of view of the speckle images is smaller than that of the AO images, about 3'' on each side, but the PSF widths are narrower (0.02''-0.05''), resulting in better spatial resolution. Some of the results on DSSI observations of KOIs can be found in Howell et al. 2011 (Cat. J/AJ/142/19), Horch et al. ( 2012AJ....144..165H, 2014ApJ...795...60H), Everett et al. (2015AJ....149...55E), and Teske et al. (2015AJ....150..144T). Wang et al. (2015ApJ...806..248W, 2015ApJ...813..130W) used the adaptive optics systems at Keck and Palomar with NIRC2 and PHARO, respectively, and typically observed each target with the J-, H-, and K-band filters. Adams et al. 2012 (Cat. J/AJ/144/42), Adams et al. (2013AJ....146....9A) and Dressing et al. (2014AJ....148...78D) mainly used the Ks filter in their AO observations at the MMT; in addition, they often used the J-band filter when a companion was detected in the Ks image. The field of view of the ARIES instrument on the MMT was 20''*20'', somewhat smaller than that of PHARO at Palomar, and the FWHM of the stellar images varied between about 0.1'' and 0.6''. Kraus et al. 2016 (Cat. J/AJ/152/8) employed adaptive optics imaging and also non-redundant aperture-mask interferometry at Keck with the NIRC2 instrument; the latter technique is limited only by the diffraction limit of the 10m Keck telescope. They used the K' filter for their observations. Baranec et al. 2016 (Cat. J/AJ/152/18) and Ziegler et al. 2016 (AJ accepted, arXiv:1605.03584) observed a sample of KOI host stars at Keck using mostly the K' filter on NIRC2. With the Robo-AO imaging at the Palomar 1.5m telescope, Law et al. 2014 (Cat. J/ApJ/791/35), Baranec et al. 2016 (Cat. J/AJ/152/18), and Ziegler et al. 2016 (AJ accepted, arXiv:1605.03584) covered a total of 3320 KOI host stars. For most observations, they used a long-pass filter whose window starts at 600nm (LP600), which is similar to the Kepler bandpass; they also took data for some stars in the Sloan i-band filter and, more rarely, Sloan r and z filters. The typical FWHM of the observed stellar PSF amounted to 0.12''-0.15''; the images covered a field of view of 44''*44''. Lillo-Box et al. (2012, Cat. J/A+A/546/A10; 2014, Cat. J/A+A/566/A103) used the 2.2m Calar Alto telescope with the AstraLux instrument to obtain diffraction-limited imaging with the lucky imaging technique, typically observing in the i- and z-band filters. This technique involves taking a very large number of short exposures and then combining only those images with the best quality (i.e., with the highest Strehl ratios). The FWHM of the stellar PSF in their 24''*24'' images was typically 0.21'', which is somewhat larger than the value from AO images (~0.15''). HST imaging using WFC3 was carried out in the F555W and F775W bands (Cartier et al. 2015ApJ...804...97C; Gilliland et al. 2015AJ....149...24G). The images spanned a relatively large field of view of 40''*40'', and the typical FWHM of the stellar PSF was 0.08''. One additional facility, the 8m Large Binocular Telescope, was used with LMIRCam to observe 24 KOI host stars in the Ks band, but results have not yet been published and are not available on CFOP. Except for 1 of these 24 stars (which has only one false positive transit signal), all have been observed with one or more other facilities too. The Kepler field was observed at the United Kingdom Infrared Telescope (UKIRT) in 2010 using the UKIRT Wide Field Camera (WFCAM). The images were taken in the J band and have a typical spatial resolution of 0.8''-0.9''. Everett et al. (2012PASP..124..316E) carried out a survey of the Kepler field in 2011 using the NOAO Mosaic-1.1 Wide Field Imager on the WIYN 0.9m telescope. They observed the field in UBV filters; the FWHM of the stellar PSF due to seeing ranged from 1.2'' to 2.5'' in the V-band (with somewhat larger values in the U and B band). The source catalog and the images are available on CFOP. (6 data files).
Eating on an interconnected planet
NASA Astrophysics Data System (ADS)
MacDonald, Graham K.
2013-06-01
Calls to boost agricultural production in order to meet the demands of a growing global population are now commonplace. Yet, depending on where productivity changes and population growth occur, international trade could be increasingly necessary in the transfer of food from farms to consumers. Fader et al (2013) offer a nuanced view of this spatial disconnect and its food security implications by considering a valuable thought experiment: what countries could foreseeably meet their food requirements from internal production alone circa 2000 and for contrasting scenarios in 2050? They investigate the extent to which available renewable water and land resources constrain domestic per capita crop production, assuming current as well as broadly improved yields. The findings convey an intuitive, though often overlooked, point that population growth is likely to increase the reliance of certain regions on food imports unless substantial productivity improvements are realized. It is unlikely that any nation would be compelled to produce all of its food domestically, but reflecting on potential food self-sufficiency is a worthwhile endeavor. Importing crops may be matter of choice, but also one of necessity if available land, water, and yields limit production. Dependence on food imports can involve uncertainty: production shortfalls arising from drought and other factors have been associated with price volatility—or even restrictions on crop exports—posing challenges to countries anticipating consistent import arrangements (Headey 2011). Compounding this uncertainty is that a relatively small number of countries produce the bulk of staple crops for global markets. Just eight countries comprising 11% of the global population produced, on average, 70% of cereal exports during the past decade (FAO 2013). Although trade networks are dynamic, some net-importing countries have developed entrenched relationships with particular producers that entail very large crop transfers (Carr et al 2012). A central finding of Fader et al 's study is that domestic crop production could theoretically replace imports and allow food self-sufficiency in many countries. Embracing this potential could lessen the need to increase imports as populations grow. Yet, in their extreme scenario—assuming no yield improvements, no agricultural expansion and high population growth rates—roughly 51% of the global population would be import dependent by 2050. While improbable, this case raises the question of how such a spike in crop demands might ricochet across producing countries. Exporters could alter their production and export rates in response to various internal or external drivers, such as land-use policies, concerns over grain stocks, or climate change impacts (Hertel et al 2010, Lambin and Meyfroidt 2011, Headey 2011). Suweis et al (2013) suggest that water-rich nations are unlikely to maintain their current crop export rates amidst global change, questioning the persistence of global food trade relationships in the absence of mitigative actions. The uneven role of a relatively small number of nations to the food security of many is apparent when considering the origins of key crops imported by countries that Fader et al estimate have already crossed a resource boundary limiting food self-sufficiency (figure 1). Figure 1. Figure 1. The origins of key crops (maize, milled/paddy rice, soybean, and wheat) imported by 49 countries that have exceeded a land or water constraint boundary currently limiting food self-sufficiency. The map of countries exceeding at least one boundary circa 2000, shaded in black, is based on figure 1(B) in Fader et al (2013). The size of the lines indicate the relative quantity of kilocalories imported, calculated using FAO (2013) import matrices and crop kilocalorie contents (FAO 2001) averaged for the period 2000-2010. Internal trade among countries that had exceeded a land or water boundary totaled ~6%. Small island nations and 11 countries not reporting import origin data were omitted here. Fader et al 's potential crop production estimates are derived from a comprehensive global model, but several factors could compound import dependence or shift yield trajectories. Growing meat consumption that typically coincides with rising average incomes will drive increased demand for crops across some regions surpassing that of population growth (Delgado 2003, Kastner et al 2012). Such trends would exacerbate direct or indirect reliance on foreign land and water resources. Comparison of global crop productivity simulations with regional crop response models would help to better understand how management interventions (Lobell et al 2009) and changing climate (Thornton et al 2009) positively or negatively impact attainable per capita production across regions. Moreover, the cropland expansion scenarios used in Fader et al 's study are optimistic in that they draw on a sizable land base of 13.2 million km2, which, if fully utilized, would be an almost doubling of the 15.1 million km2 under production in 2000 (FAO 2013). We already use much of the world's prime arable lands, with stagnating yield trends for key crops in some locations, so realizing equivalent yields from a vast new area is unlikely (Foley et al 2011, Ray et al 2012). Considering how specific farm management and demand-driven feedbacks alter trade patterns would provide valuable juxtaposition to Fader et al 's benchmark study. Ultimately, equity and cooperation among countries may be increasingly critical to regional food security if locations of food production and consumption continue to diverge. Even with large increases in yields and widespread cropland expansion, Fader et al (2013) project that up to 30 countries—largely low-income economies—will remain import dependent due to resource constraints. Food security in poorer countries most vulnerable to productivity shocks and price volatility depends on the ability of certain populations to afford imports (Naylor and Falcon 2010). Future changes in agricultural commodity prices tied to yield variations could disproportionately impact the welfare of specific households, while possibly benefiting other lower income countries that produce exports (Hertel et al 2010). In the event that import dependence rises markedly from 16% of the global population circa 2000 (Fader et al 2013), cooperative trade policies may be pivotal to alleviating food insecurity of the most vulnerable net-food importing countries (Bouët and Debucquet 2012). Quantifying the capacity of countries to meet their per capita crop requirements underpins the importance of truly widespread yield improvements, particularly given the already concentrated nature of export production. Fader et al 's study offers new insight on how the growing spatial disconnect between where people live and where food is grown may dictate either increasingly entrenched dependence on foreign production or immense cropland expansion throughout net-importing countries. Framing this challenge in terms of potential domestic crop production reveals that even small yield improvements could go a long way toward easing both. Acknowledgments I thank K Carlson, J Foley, P West, M Schipanski, and N Mueller for comments. References Bouët A and Debucquet D 2012 Food crisis and export taxation: the cost of non-cooperative trade policies Rev. World Econom. 148 209-33 Carr J A, D'Odorico P, Laio F and Ridolfi L 2012 On the temporal variability of the virtual water network Geophys. Res. Lett. 39 L06404 Delgado C L 2003 Rising consumption of meat and milk in developing countries has created a new food revolution J. Nutr. 133 3907S-10S Fader M, Gerten D, Krause M, Lucht W and Cramer W 2013 Spatial decoupling of agricultural production and consumption: quantifying dependence of countries on food imports due to domestic land and water constraints Environ. Res. Lett. 8 014046 FAO (Food and Agriculture Organization) 2001 Food Balance Sheets: A Handbook (Rome: United Nations Food and Agriculture Organization) FAO (Food and Agriculture Organization) 2013 FAOSTAT: FAO Statistical Databases (Rome: United Nations Food and Agriculture Organization) Foley J A et al 2011 Solutions for a cultivated planet Nature 478 337-42 Headey D 2011 Rethinking the global food crisis: the role of trade shocks Food Policy 36 136-46 Hertel T W, Burke M B and Lobell D B 2010 The poverty implications of climate-induced crop yield changes by 2030 Glob. Environ. Change 20 577-85 Kastner T, Rivas M J I, Koch W and Nonhebel S 2012 Global changes in diets and the consequences for land requirements for food Proc. Natl Acad. Sci. 109 6868-72 Lambin E F and Meyfroidt P 2011 Global land use change, economic globalization, and the looming land scarcity Proc. Natl Acad. Sci. 108 3465-72 Lobell D B, Cassman K G and Field C B 2009 Crop yield gaps: their importance, magnitudes, and causes Annu. Rev. Environ. Resour. 34 179 Naylor R L and Falcon W P 2010 Food security in an era of economic volatility Popul. Dev. Rev. 36 693-723 Ray D K, Ramankutty N, Mueller N D, West P C and Foley J A 2012 Recent patterns of crop yield growth and stagnation Nature Commun. 3 1293 Suweis S, Rinaldo A, Maritan A and D'Odorico P 2013 Water-controlled wealth of nations Proc. Natl Acad. Sci. 110 4230-3 Thornton P K, Jones P G, Alagarswamy G and Andresen J 2009 Spatial variation of crop yield response to climate change in East Africa Glob. Environ. Change 19 54-65
EDITORIAL: Focus on Iron-Based Superconductors FOCUS ON IRON-BASED SUPERCONDUCTORS
NASA Astrophysics Data System (ADS)
Hosono, Hideo; Ren, Zhi-An
2009-02-01
Superconductivity is the most dramatic and clear cut phenomenon in condensed matter physics. Realization of room temperature superconductors, which would lead to the revolution of our society, is an ultimate goal for researchers. The discovery of high Tc cuprate superconductors in 1986 by Bednorz and Müller triggered intensive research worldwide and the maximum critical temperature has been raised above 100 K. Scientific research on this break-through material clarified a new route to high Tc materials, carrier doping to a Mott insulator with anti-ferromagnetic ordering. High superconductivity occurs in the neighborhood of Mott-insulators and Fermi-metals. Such a view, which was completely new, now stands as a guiding principle for exploring new high Tc materials. Many theoretical approaches to the mechanism for cuprate superconductors have been carried out to understand this unexpected material and to predict new high Tc materials. In 2006 a new superconductor based on iron, LaFeOP, was discovered by a group at Tokyo Institute of Technology, Japan. Iron, as a ferromagnet, was believed to be the last element for the realization of superconductivity because of the way ferromagnetism competes against Cooper pair formation. Unexpectedly, however, the critical temperature remained at 4-6 K irrespective of hole/electron-doping. A large increase in the Tc to 26 K was then found in LaFe[O1-xFx]As by the same group (and was published on 23 February 2008, in the Journal of the American Chemical Society). The Tc of this material was further raised to 43 K under a pressure of 2 GPa and scientists in China then achieved a Tc of 56 K at ambient pressure by replacing La with other rare earth ions with smaller radius—a critical temperature that is second only to the high Tc cuprates. This fast progress has revitalized research within superconductivity and in 2008 there were more than seven international symposia specifically on Fe(Ni)-based superconductors. Through the rapid pace of research within the last year, iron-based superconductors have revealed several unique properties such as a high upper critical field and a robustness to impurities. Participation of five 3d-orbitals in the Fermi levels also means that the electronic structure is complex compared with the cuprates. So, we now have a new family of superconductors and it is worth stressing that we have only just begun looking at the many varieties of candidate materials containing an iron square lattice. At this time we do not know whether a material with a critical temperature greater than 100 K exists, or if completely new properties are to be found. However, as a research community we should go ahead with hope and 'strike while the iron is hot'—this saying is always true! This focus issue of New Journal of Physics was put together to provide a broad-based, free-to-read snapshot of the current state of research in this rapidly emerging field. The papers included cover many aspects related to material exploration, physical analysis, and the theory of these materials, and, as editors, we thank the authors for their fine contributions, and the many referees for their considerable efforts that have ensured fast publication. As an aside, the first special issue on this SUBject was published in November 2008 in the Journal of the Physical Society of Japan (vol 77, supplement c) as the proceedings of the International Symposium on Iron-Pnictide Superconductors held in Tokyo on 29-30 June 2008. We would like to encourage the community to read both issues. On a final note we would like to acknowledge the staff of New Journal of Physics for all of their efficient work in bringing this collection to fruition. Focus on Iron-Based Superconductors Contents Microwave response of superconducting pnictides: extended s+/- scenario O V Dolgov, A A Golubov and D Parker Orbital and spin effects for the upper critical field in As-deficient disordered Fe pnictide superconductors G Fuchs, S-L Drechsler, N Kozlova, M Bartkowiak, J E Hamann-Borrero, G Behr, K Nenkov, H-H Klauss, H Maeter, A Amato, H Luetkens, A Kwadrin, R Khasanov, J Freudenberger, A Köhler, M Knupfer, E Arushanov, H Rosner, B Büchner and L Schultz Low-energy spin dynamics in the antiferromagnetic phase of CaFe2As2 N J Curro, A P Dioguardi, N ApRoberts-Warren, A C Shockley and P Klavins Muon spin rotation study of magnetism and superconductivity in BaFe2-xCoxAs2 and Pr1-xSrxFeAsO C Bernhard, A J Drew, L Schulz, V K Malik, M Rössle, Ch Niedermayer, Th Wolf, G D Varma, G Mu, H-H Wen, H Liu, G Wu and X H Chen Magnetic impurities in the pnictide superconductor Ba1-xKxFe2As2 Sutirtha Mukhopadhyay, Sangwon Oh, A M Mounce, Moohee Lee, W P Halperin, N Ni, S L Bud'ko, P C Canfield, A P Reyes and P L Kuhns Neutron scattering investigation of the magnetic order in single crystalline BaFe2As2 M Kofu, Y Qiu, Wei Bao, S-H Lee, S Chang, T Wu, G Wu and X H Chen An NMR study on the F-doping evolution of the iron oxypnictide LaFeAs(O1-xFx) Y Nakai, S Kitagawa, K Ishida, Y Kamihara, M Hirano and H Hosono The peculiar physical properties and phase diagram of BaFe2-xCoxAs2 single crystals X F Wang, T Wu, G Wu, R H Liu, H Chen, Y L Xie and X H Chen Synthesis of LnFeAsO1-y superconductors (Ln=La and Nd) using the high-pressure technique Kiichi Miyazawa, Kunihiro Kihou, Motoyuki Ishikado, Parasharam M Shirage, Chul-Ho Lee, Nao Takeshita, Hiroshi Eisaki, Hijiri Kito and Akira Iyo Correlation effects in the iron pnictides Qimiao Si, Elihu Abrahams, Jianhui Dai and Jian-Xin Zhu Competition/coexisitence of magnetism and superconductivity in iron pnictides probed by muon spin rotation Soshi Takeshita and Ryosuke Kadono Impurity-induced in-gap state and Tc in sign-reversing s-wave superconductors: analysis of iron oxypnictide superconductors Yuko Senga and Hiroshi Kontani Intrinsic magnetic properties of the superconductor NdFeAsO0.9F0.1 from local and global measurements R Prozorov, M E Tillman, E D Mun and P C Canfield Elastic theory for the vortex-lattice melting in iron-based high-Tc superconductors Q-H Chen, Q-M Nie, J-P Lv and T-C Au Yeung Electronic properties of LaO1-xFxFeAs in the normal state probed by NMR/NQR H-J Grafe, G Lang, F Hammerath, D Paar, K Manthey, K Koch, H Rosner, N J Curro, G Behr, J Werner, N Leps, R Klingeler, H-H Klauss, F J Litterst and B Büchner AFe2As2 (A = Ca, Sr, Ba, Eu) and SrFe2-xTMxAs2 (TM = Mn, Co, Ni): crystal structure, charge doping, magnetism and superconductivity Deepa Kasinathan, Alim Ormeci, Katrin Koch, Ulrich Burkhardt, Walter Schnelle, Andreas Leithe-Jasper and Helge Rosner Impurity states in a family of antiferromagnetic iron arsenides Qiang Han and Z D Wang Coherence-incoherence crossover in the normal state of iron oxypnictides and importance of Hund's rule coupling K Haule and G Kotliar Electronic structure of heavily electron-doped BaFe1.7Co0.3As2 studied by angle-resolved photoemission Y Sekiba, T Sato, K Nakayama, K Terashima, P Richard, J H Bowen, H Ding, Y-M Xu, L J Li, G H Cao, Z-A Xu and T Takahashi Absorption and photoemission spectroscopy of rare-earth oxypnictides T Kroll, F Roth, A Koitzsch, R Kraus, D R Batchelor, J Werner, G Behr, B Büchner and M Knupfer Superconductivity in LnFePO (Ln = La, Pr and Nd) single crystals R E Baumbach, J J Hamlin, L Shu, D A Zocco, N M Crisosto and M B Maple Unconventional pairing originating from disconnected Fermi surfaces in the iron-based superconductor Kazuhiko Kuroki, Seiichiro Onari, Ryotaro Arita, Hidetomo Usui, Yukio Tanaka, Hiroshi Kontani and Hideo Aoki Near-degeneracy of several pairing channels in multiorbital models for the Fe pnictides S Graser, T A Maier, P J Hirschfeld and D J Scalapino Investigation of superconducting gap structure in TbFeAsO0.9F0.1 using point contact Andreev reflection K A Yates, K Morrison, J A Rodgers, G B S Penny, J-W G Bos, J P Attfield and L F Cohen Competition of magnetism and superconductivity in underdoped (Ba1-xKx)Fe2As2 Marianne Rotter, Marcus Tegel, Inga Schellenberg, Falko M Schappacher, Rainer Pöttgen, Joachim Deisenhofer, Axel Günther, Florian Schrettle, Alois Loidl and Dirk Johrendt The superconductor KxSr1-xFe2As2: normal state and superconducting properties B Lv, M Gooch, B Lorenz, F Chen, A M Guloy and C W Chu Effect of 3d transition metal doping on the superconductivity in quaternary fluoroarsenide CaFeAsF Satoru Matsuishi, Yasunori Inoue, Takatoshi Nomura, Youichi Kamihara, Masahiro Hirano and Hideo Hosono Influence of the rare-earth element on the effects of the structural and magnetic phase transitions in CeFeAsO, PrFeAsO and NdFeAsO Michael A McGuire, Raphaël P Hermann, Athena S Sefat, Brian C Sales, Rongying Jin, David Mandrus, Fernande Grandjean and Gary J Long Heat capacity measurements on FeAs-based compounds: a thermodynamic probe of electronic and magnetic states P J Baker, S R Giblin, F L Pratt, R H Liu, G Wu, X H Chen, M J Pitcher, D R Parker, S J Clarke and S J Blundell Spin fluctuations, interband coupling and unconventional pairing in iron-based superconductors Zi-Jian Yao, Jian-Xin Li and Z D Wang Superconductivity induced by Ni doping in BaFe2As2 single crystals L J Li, Y K Luo, Q B Wang, H Chen, Z Ren, Q Tao, Y K Li, X Lin, M He, Z W Zhu, G H Cao and Z A Xu Metamagnetic transition in EuFe2As2 single crystals Shuai Jiang, Yongkang Luo, Zhi Ren, Zengwei Zhu, Cao Wang, Xiangfan Xu, Qian Tao, Guanghan Cao and Zhu'an Xu Pressure dependence of the thermoelectric power of the iron-based high-Tc superconductor SmFeAsO0.85 N Kang, P Auban-Senzier, C R Pasquier, Z A Ren, J Yang, G C Che and Z X Zhao Superconductivity in some heavy rare-earth iron arsenide REFeAsO1-δ (RE = Ho, Y, Dy and Tb) compounds Jie Yang, Xiao-Li Shen, Wei Lu, Wei Yi, Zheng-Cai Li, Zhi-An Ren, Guang-Can Che, Xiao-Li Dong, Li-Ling Sun, Fang Zhou and Zhong-Xian Zhao The delicate electronic and magnetic structure of the LaFePnO system (Pn = pnicogen) S Lebègue, Z P Yin and W E Pickett
STUDIES ON THE TUBERCULIN REACTION AND ON SPECIFIC HYPERSENSITIVENESS IN BACTERIAL INFECTION
Zinsser, Hans
1921-01-01
The work reported in the preceding sections justifies, we think, a number of definite conclusions. In addition to this, some of the experiments indicate a line of thought which may lead to considerable alteration in our conceptions, both of phenomena of bacterial hypersensitiveness and of infection. 1. In guinea pigs two fundamentally different types of intradermal reactions may be observed. One of these is the immediate, transitory reaction which develops in animals sensitized against proteins (horse serum, etc.) and may be regarded as one of the manifestations of general protein hypersensitiveness, or anaphylaxis; the other is the tuberculin type of skin reaction which develops more slowly, leads to a more profound injury of the tissues and is independent of anaphylaxis as ordinarily conceived. 2. The tuberculin type of hypersensitiveness (as well as probably the typhoidin, mallein, abortin reactions, etc.) does not develop at all in guinea pigs sensitized with proteins, like horse serum, etc. While this form of hypersensitiveness may eventually be induced with materials not bacterial in origin, it has been observed up to date only as a reaction of bacterial infection. 3. Methods of treatment with protein material from bacterial cultures which sensitize guinea pigs to anaphylactic reactions with the bacterial extracts, do not sensitize them to the tuberculin type of reaction. Such sensitization is easily accomplished only by infecting the animals with living organisms. No reliable method of sensitizing guinea pigs to such reactions with dead bacterial material has as yet been worked out, though a few hopeful experiments have been obtained with massive injections of large amounts of the acid-precipitable substances (nucleoproteins?) from bacterial extracts. 4. In animals made hypersensitive to the tuberculin type of reaction by infection with living bacteria, the reaction may be elicited by intradermal injections of bacterial extracts from which all coagulable proteins, nucleoproteins, and Bence-Jones proteins have been removed, as well as this can be done by boiling with acid, etc. This proteose residue alone suffices to elicit such reactions. The exact chemical nature of the so called proteose residue must be further studied and analyzed when we have had opportunity to produce bacterial extracts in large quantity. These points seem incontrovertible on the basis of our own experiments, as well as those of other workers. There thus seem to develop two definite forms of hypersensitiveness in guinea pigs infected with bacteria, typical anaphylaxis in which the protein material of the bacterial cells is concerned, which develops late and which can be induced by repeated injections of dead bacterial material, and a hypersensitiveness to non-protein constituents which differs from the former, both in the laws that govern sensitization and in the manifestations which follow injections into the sensitized animals. While there is virtual agreement among immunologists concerning the essential mechanism of protein anaphylaxis, its dependence upon an antigen-antibody reaction, and the dominating rôle played by the sessile antibodies, the mechanism of hypersensitiveness to tuberculin and similar bacterial substances is still a problem of much uncertainty. The most striking difference between the two phenomena lies, as we have seen, in the criteria of sensitization, in that hypersensitiveness to the tuberculin type of reaction can hardly ever be induced by any of the ordinary methods of preparation with the constituents of dead bacteria, but develops promptly (7 to 10 days) in the course of actual infection with living organisms. The considerable specificity of such reactions forces the conclusion that the sensitizing substance must, in some way, be derived from the infecting microorganisms. The idea that the failure of sensitization with dead culture materials is perhaps due to the elaboration in the body of infected animals of bacterial products not represented in extracts of test-tube cultures is rendered unlikely by the fact that in the tuberculin-sensitive, infected animals, we can produce the reactions by the application of such dead extracts. It is neither logical nor in keeping with biological experience to assume that one substance will sensitize to reaction with another. This mistake was made early in the study of anaphylaxis in another connection and caused considerable delay of progress. Krause has shown that tuberculin sensitiveness may be blunted in infected animals by massive, but sublethal injections of tuberculin, and we have obtained some indications of the same thing. Moreover, others as well as ourselves have seen tuberculin reactivity decline in guinea pigs and in man in the stages of very severe infection. These facts would eliminate any assumption of mere cumulative injury as explaining this type of reaction, and stamp it as a mechanism at least analogous to ordinary anaphylaxis. The only remaining possibility to explain the difference between infected animals and those treated with dead bacterial constituents would be to assume that the difference must lie in the manner in which the sensitizing substance is administered to the animals, and that sensitization with the proteose residue materials depends upon criteria of sensitization differing in regard to the time and quantity factors from those governing protein sensitization. If one considers the relatively simpler chemical structure and perhaps physically greater diffusibility of the materials concerned in this reaction, one might readily expect such differences in the methods needed for sensitization. In keeping with such a line of reasoning our experiments have shown that the tuberculin active materials are constantly and rapidly being diffused out into the culture fluid from growing organisms, in quantities greater than can be extracted from similar amounts of the dead bacteria. It seems reasonable to assume from this that the same thing may happen in the animal body harboring a growing focus. And it would seem quite likely that the association of the tuberculin type of reaction with actual infection may depend upon the fact that sensitization to these non-protein substances depends upon a constant steady absorption of large amounts of the material. Moreover, the only hopeful experiments on the artificial production of tuberculin sensitiveness in guinea pigs obtained by us were those in which massive doses of the nucleoprotein material injected into guinea pigs gave rise to a moderate skin sensitiveness. Does the so called proteose residue form antibodies, and, if so, are substances analogous to antibodies involved in the tuberculin type of hypersensitiveness? The failure to transfer passively this form of hypersensitiveness to normal animals with the blood and tissues of tuberculin-sensitive ones would suggest that no antibodies are involved. But this is not conclusive on the basis of available experimental facts. We are inclined to believe that antibodies of a sort are involved, for the following reasons: (a) In our experiments with the uteri of highly sensitive extract-treated guinea pigs and of tuberculous guinea pigs, we have occasionally had positive reactions when the proteose residue alone was used. (b) We believe that these proteose substances are entirely analogous to the substances studied by Avery and Dochez (22) in the urine and blood of typhoid and pneumonia patients. They obtained precipitin reactions against homologous immune sera with the urine of infected cases concentrated by evaporation after boiling with acetic acid to remove coagulable proteins. (c) Petroff, with whom we discussed this proteose residue early in our work, has produced it, and tells us that he has obtained precipitin reactions with it by titrating it against the serum of a sheep treated for a long time with tubercle bacillus products. In suggesting an antibody response to a non-protein antigen we are aware that we are opposing what has been regarded as a well established doctrine in immunity; this is justified, or at least mitigated, we believe, by the consideration that reactions of the antigen-antibody type are the only explanation of specificity; and tuberculin, mallein, and typhoidin reactions are to a considerable degree specific. If such reaction bodies cannot be produced by precisely the same methods of administration as to time and quantity which are successful in calling forth protein antibodies, this should not astonish us, since, after all, the substances that we are dealing with are simpler in chemical structure than are the proteins, and physically are probably of relatively greater diffusibility. It may be that the greater diffusibility of the proteose-like substances transfers much of the actual reaction phenomena to an intracellular location, and that this to some extent influences the presence of circulating antibodies. It may also be that these more diffusible non-protein antigens are more rapidly eliminated from the animal body than are the proteins. Indeed, the above mentioned observations of Avery and Dochez, and the recent work of Wildbolz (23), Lanz (24), Imhof (25), and Gibson and Carroll (26), who demonstrated tuberculin active antigens in the urine of active cases, would corroborate such a view. The evidence available at the present time, however, concerning antibody formation to these non-protein substances is, we recognize, largely indirect, at least as far as our own work is concerned, and we present it in the present connection purely as a working hypothesis. Finally, perhaps the most important theoretical consideration indicated by our experiments is the following. We have in the tuberculin reaction a form of hypersensitiveness which seems to be (in guinea pigs, at least) analogous entirely to the typhoidin reaction, the mallein reaction, and the abortin reaction. Whenever reactions of this type have been carefully studied, whatever the bacteria involved, they have been associated with infection as in tuberculosis, and have been followed by analogous clinical manifestations. It would seem perhaps that we are dealing with a law applicable to bacterial infection in general. It would appear that certain non-coagulable substances of uncertain chemical constitution are being constantly elaborated in the course of bacterial growth, and passed into the circulation of infected animals. As a result of this, infected animals become sensitized to these heat-and acid-resistant materials, in tuberculosis in the course of I to 2 weeks, in the case of more rapidly growing bacteria perhaps sooner. Early in the course of infection, the animal becomes sensitized and subsequently the further elaboration and distribution of these materials from the bacterial focus plays a fundamental part in the injury of the animal. These proteose-like substances, like tuberculin, possessing but slight toxicity for the normal animal, become highly toxic to the sensitized one. Thus, these substances, while not being true exotoxins in the ordinary sense, would still represent a highly toxic bacterial product comparable in its injurious effect to toxins when produced in the body of an animal thus sensitized. If there is any value in these deductions the attention of bacteriologists should be turned to the non-protein constituents of bacterial cells in their further immunological studies, as well as to the protein materials. It is obvious that the next step in our investigations must consist in producing the non-coagulable material from bacterial extracts in considerable quantity, to determine their antibody-forming properties in detail, and elucidate, if possible, the laws which govern sensitization with them. This work has been begun, but it has seemed advisable to publish this as far as we have gone because it will take a long time before it can be completed. PMID:19868574