Science.gov

Sample records for allowing direct observation

  1. Dipole-allowed direct band gap silicon superlattices.

    PubMed

    Oh, Young Jun; Lee, In-Ho; Kim, Sunghyun; Lee, Jooyoung; Chang, Kee Joo

    2015-01-01

    Silicon is the most popular material used in electronic devices. However, its poor optical properties owing to its indirect band gap nature limit its usage in optoelectronic devices. Here we present the discovery of super-stable pure-silicon superlattice structures that can serve as promising materials for solar cell applications and can lead to the realization of pure Si-based optoelectronic devices. The structures are almost identical to that of bulk Si except that defective layers are intercalated in the diamond lattice. The superlattices exhibit dipole-allowed direct band gaps as well as indirect band gaps, providing ideal conditions for the investigation of a direct-to-indirect band gap transition. The fact that almost all structural portions of the superlattices originate from bulk Si warrants their stability and good lattice matching with bulk Si. Through first-principles molecular dynamics simulations, we confirmed their thermal stability and propose a possible method to synthesize the defective layer through wafer bonding. PMID:26656482

  2. Dipole-allowed direct band gap silicon superlattices

    PubMed Central

    Oh, Young Jun; Lee, In-Ho; Kim, Sunghyun; Lee, Jooyoung; Chang, Kee Joo

    2015-01-01

    Silicon is the most popular material used in electronic devices. However, its poor optical properties owing to its indirect band gap nature limit its usage in optoelectronic devices. Here we present the discovery of super-stable pure-silicon superlattice structures that can serve as promising materials for solar cell applications and can lead to the realization of pure Si-based optoelectronic devices. The structures are almost identical to that of bulk Si except that defective layers are intercalated in the diamond lattice. The superlattices exhibit dipole-allowed direct band gaps as well as indirect band gaps, providing ideal conditions for the investigation of a direct-to-indirect band gap transition. The fact that almost all structural portions of the superlattices originate from bulk Si warrants their stability and good lattice matching with bulk Si. Through first-principles molecular dynamics simulations, we confirmed their thermal stability and propose a possible method to synthesize the defective layer through wafer bonding. PMID:26656482

  3. Direct observation of time reversal violation

    NASA Astrophysics Data System (ADS)

    Bernabéu, J.

    2013-06-01

    A direct evidence for Time Reversal Violation (TRV) means an experiment that, considered by itself, clearly shows TRV independent of, and unconnected to, the results for CP Violation. No existing result before the recent BABAR experiment with entangled neutral B mesons had demonstrated TRV in this sense. There is a unique opportunity for a search of TRV with unstable particles thanks to the Einstein-Podolsky-Rosen (EPR) Entanglement between the two neutral mesons in B, and PHI, Factories. The two quantum effects of the first decay as a filtering measurement and the transfer of information to the still living partner allow performing a genuine TRV asymmetry with the exchange of "in" and "out" states. With four independent TRV asymmetries, BABAR observes a large deviation of T-invariance with a statistical significance of 14 standard deviations, far more than needed to declare the result as a discovery. This is the first direct observation of TRV in the time evolution of any system.

  4. 30 CFR 1220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... event of oil spills or other environmental damage are allowable. The costs of actual control and cleanup of oil spills and resulting responsibilities required by applicable laws and regulations are... PAYMENT FOR OUTER CONTINENTAL SHELF OIL AND GAS LEASES § 1220.011 Schedule of allowable direct...

  5. 30 CFR 1220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... event of oil spills or other environmental damage are allowable. The costs of actual control and cleanup of oil spills and resulting responsibilities required by applicable laws and regulations are... PAYMENT FOR OUTER CONTINENTAL SHELF OIL AND GAS LEASES § 1220.011 Schedule of allowable direct...

  6. 30 CFR 220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... event of oil spills or other environmental damage are allowable. The costs of actual control and cleanup of oil spills and resulting responsibilities required by applicable laws and regulations are... PAYMENT FOR OUTER CONTINENTAL SHELF OIL AND GAS LEASES § 220.011 Schedule of allowable direct...

  7. 30 CFR 1220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... event of oil spills or other environmental damage are allowable. The costs of actual control and cleanup of oil spills and resulting responsibilities required by applicable laws and regulations are... PAYMENT FOR OUTER CONTINENTAL SHELF OIL AND GAS LEASES § 1220.011 Schedule of allowable direct...

  8. Direct Observations of Structural Phase Transitions in

    E-print Network

    California at San Diego, University of

    observed in Paul traps (17). With larger numbers of trapped ions, concentric shells (18) were di- rectly plasmas confined in a Penning trap (4). Measurements were taken from direct images of the central (r 0 observed five different stable crystalline phases and found that the energetically favorable central

  9. Direct observation limits on antimatter gravitation

    SciTech Connect

    Fischler, Mark; Lykken, Joe; Roberts, Tom; /Fermilab

    2008-06-01

    The proposed Antihydrogen Gravity experiment at Fermilab (P981) will directly measure the gravitational attraction g between antihydrogen and the Earth, with an accuracy of 1% or better. The following key question has been asked by the PAC: Is a possible 1% difference between g and g already ruled out by other evidence? This memo presents the key points of existing evidence, to answer whether such a difference is ruled out (a) on the basis of direct observational evidence; and/or (b) on the basis of indirect evidence, combined with reasoning based on strongly held theoretical assumptions. The bottom line is that there are no direct observations or measurements of gravitational asymmetry which address the antimatter sector. There is evidence which by indirect reasoning can be taken to rule out such a difference, but the analysis needed to draw that conclusion rests on models and assumptions which are in question for other reasons and are thus worth testing. There is no compelling evidence or theoretical reason to rule out such a difference at the 1% level.

  10. First direct observation of muon antineutrino disappearance

    SciTech Connect

    Adamson, P.

    2011-07-05

    This letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ??? production, accumulating an exposure of 1.71 x 1020 protons on target. In the Far Detector, 97 charged current ??? events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3?. The best fit to oscillation yields |?m?2| = (3.36-0.40 +0.46(stat.) ± 0.06(syst.)) x 10-3 eV2, sin2(2 ??) = 0.86-0.12+0.11 (stat.) ± 0.01(syst.). The MINOS ?? and ??? measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

  11. Direct observation of laser guided corona discharges

    PubMed Central

    Wang, Tie-Jun; Wei, Yingxia; Liu, Yaoxiang; Chen, Na; Liu, Yonghong; Ju, Jingjing; Sun, Haiyi; Wang, Cheng; Lu, Haihe; Liu, Jiansheng; Chin, See Leang; Li, Ruxin; Xu, Zhizhan

    2015-01-01

    Laser based lightning control holds a promising way to solve the problem of the long standing disaster of lightning strikes. But it is a challenging project due to insufficient understanding of the interaction between laser plasma channel and high voltage electric filed. In this work, a direct observation of laser guided corona discharge is reported. Laser filament guided streamer and leader types of corona discharges were observed. An enhanced ionization took place in the leader (filament) through the interaction with the high voltage discharging field. The fluorescence lifetime of laser filament guided corona discharge was measured to be several microseconds, which is 3 orders of magnitude longer than the fluorescence lifetime of laser filaments. This work could be advantageous towards a better understanding of laser assisted leader development in the atmosphere. PMID:26679271

  12. First direct observation of muon antineutrino disappearance

    DOE PAGESBeta

    Adamson, P.

    2011-07-05

    This letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ??? production, accumulating an exposure of 1.71 x 1020 protons on target. In the Far Detector, 97 charged current ??? events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3?. The best fit to oscillation yields |?m?2| = (3.36-0.40 +0.46(stat.) ± 0.06(syst.)) x 10-3 eV2, sin2(2 ??) = 0.86-0.12+0.11 (stat.) ± 0.01(syst.). The MINOS ?? and ??? measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

  13. Direct observation of laser guided corona discharges.

    PubMed

    Wang, Tie-Jun; Wei, Yingxia; Liu, Yaoxiang; Chen, Na; Liu, Yonghong; Ju, Jingjing; Sun, Haiyi; Wang, Cheng; Lu, Haihe; Liu, Jiansheng; Chin, See Leang; Li, Ruxin; Xu, Zhizhan

    2015-01-01

    Laser based lightning control holds a promising way to solve the problem of the long standing disaster of lightning strikes. But it is a challenging project due to insufficient understanding of the interaction between laser plasma channel and high voltage electric filed. In this work, a direct observation of laser guided corona discharge is reported. Laser filament guided streamer and leader types of corona discharges were observed. An enhanced ionization took place in the leader (filament) through the interaction with the high voltage discharging field. The fluorescence lifetime of laser filament guided corona discharge was measured to be several microseconds, which is 3 orders of magnitude longer than the fluorescence lifetime of laser filaments. This work could be advantageous towards a better understanding of laser assisted leader development in the atmosphere. PMID:26679271

  14. Transgenic, Fluorescent Leishmania mexicana Allow Direct Analysis of the Proteome of Intracellular Amastigotes*S?

    PubMed Central

    Paape, Daniel; Lippuner, Christoph; Schmid, Monika; Ackermann, Renate; Barrios-Llerena, Martin E.; Zimny-Arndt, Ursula; Brinkmann, Volker; Arndt, Benjamin; Pleissner, Klaus Peter; Jungblut, Peter R.; Aebischer, Toni

    2008-01-01

    Investigating the proteome of intracellular pathogens is often hampered by inadequate methodologies to purify the pathogen free of host cell material. This has also precluded direct proteome analysis of the intracellular, amastigote form of Leishmania spp., protozoan parasites that cause a spectrum of diseases that affect some 12 million patients worldwide. Here a method is presented that combines classic, isopycnic density centrifugation with fluorescent particle sorting for purification by exploiting transgenic, fluorescent parasites to allow direct proteome analysis of the purified organisms. By this approach the proteome of intracellular Leishmania mexicana amastigotes was compared with that of extracellular promastigotes that are transmitted by insect vectors. In total, 509 different proteins were identified by mass spectrometry and database search. This number corresponds to ?6% of gene products predicted from the reference genome of Leishmania major. Intracellular amastigotes synthesized significantly more proteins with basic pI and showed a greater abundance of enzymes of fatty acid catabolism, which may reflect their living in acidic habitats and metabolic adaptation to nutrient availability, respectively. Bioinformatics analyses of the genes corresponding to the protein data sets produced clear evidence for skewed codon usage and translational bias in these organisms. Moreover analysis of the subset of genes whose products were more abundant in amastigotes revealed characteristic sequence motifs in 3?-untranslated regions that have been linked to translational control elements. This suggests that proteome data sets may be used to identify regulatory elements in mRNAs. Last but not least, at 6% coverage the proteome identified all vaccine antigens tested to date. Thus, the present data set provides a valuable resource for selection of candidate vaccine antigens. PMID:18474515

  15. Direct observation of laser induced freezing

    NASA Astrophysics Data System (ADS)

    Loudiyi, K.; Ackerson, Bruce J.

    1992-06-01

    The effect of an externally applied field on the microstructure of aqueous suspensions of charge stabilized polystyrene spheres is studied by direct observation. This work complements the earlier light diffraction work of Chowdhury et al., which demonstrated that radiation pressure forces can induce crystal-like microstructures in suspensions which have equilibrium liquid-like microstructures in the absence of these external fields. Specifically, a spatially periodic radiation pressure field is produced by intersecting two mutually coherent laser beams in the sample. The microstructure is observed as a function of the input intensity and crossing angle of the two laser beams, and the data is presented in terms of one and two dimensional particle distribution functions. We find that both single- and multilayered systems exhibit a transition to crystal-like order. This crystal order is more pronounced at large input power and for a periodic external field commensurate with the lattice spacing for a final undistorted two dimensional hexagonal crystal structure. Monolayer suspensions undergo this recording with no change in density, while multilayer systems restructure to a monolayer with increased layer density.

  16. Direct observation of Josephson vortex cores

    NASA Astrophysics Data System (ADS)

    Roditchev, Dimitri; Brun, Christophe; Serrier-Garcia, Lise; Cuevas, Juan Carlos; Bessa, Vagner Henrique Loiola; Miloševi?, Milorad Vlado; Debontridder, François; Stolyarov, Vasily; Cren, Tristan

    2015-04-01

    Superconducting correlations may propagate between two superconductors separated by a tiny insulating or metallic barrier, allowing a dissipationless electric current to flow. In the presence of a magnetic field, the maximum supercurrent oscillates and each oscillation corresponding to the entry of one Josephson vortex into the barrier. Josephson vortices are conceptual blocks of advanced quantum devices such as coherent terahertz generators or qubits for quantum computing, in which on-demand generation and control is crucial. Here, we map superconducting correlations inside proximity Josephson junctions using scanning tunnelling microscopy. Unexpectedly, we find that such Josephson vortices have real cores, in which the proximity gap is locally suppressed and the normal state recovered. By following the Josephson vortex formation and evolution we demonstrate that they originate from quantum interference of Andreev quasiparticles, and that the phase portraits of the two superconducting quantum condensates at edges of the junction decide their generation, shape, spatial extent and arrangement. Our observation opens a pathway towards the generation and control of Josephson vortices by applying supercurrents through the superconducting leads of the junctions, that is, by purely electrical means without any need for a magnetic field, which is a crucial step towards high-density on-chip integration of superconducting quantum devices.

  17. 30 CFR 220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...The costs of dry or bottom hole contributions made to obtain information about the structure or other characteristics of the geology underlying the NPSL tract are allowable. (n) Abandonment costs. Actual costs incurred in the plugging of wells,...

  18. 30 CFR 1220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...The costs of dry or bottom hole contributions made to obtain information about the structure or other characteristics of the geology underlying the NPSL tract are allowable. (n) Abandonment costs. Actual costs incurred in the plugging of wells,...

  19. 30 CFR 1220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...The costs of dry or bottom hole contributions made to obtain information about the structure or other characteristics of the geology underlying the NPSL tract are allowable. (n) Abandonment costs. Actual costs incurred in the plugging of wells,...

  20. Directly observed therapy for treating tuberculosis

    PubMed Central

    Karumbi, Jamlick; Garner, Paul

    2015-01-01

    Background Tuberculosis (TB) requires at least six months of treatment. If treatment is incomplete, patients may not be cured and drug resistance may develop. Directly Observed Therapy (DOT) is a specific strategy, endorsed by the World Health Organization, to improve adherence by requiring health workers, community volunteers or family members to observe and record patients taking each dose. Objectives To evaluate DOT compared to self-administered therapy in people on treatment for active TB or on prophylaxis to prevent active disease. We also compared the effects of different forms of DOT. Search methods We searched the following databases up to 13 January 2015: the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE; EMBASE; LILACS and mRCT. We also checked article reference lists and contacted relevant researchers and organizations. Selection criteria Randomized controlled trials (RCTs) and quasi-RCTs comparing DOT with routine self-administration of treatment or prophylaxis at home. Data collection and analysis Two review authors independently assessed risk of bias of each included trial and extracted data. We compared interventions using risk ratios (RR) with 95% confidence intervals (CI). We used a random-effects model if meta-analysis was appropriate but heterogeneity present (I2 statistic = 50%). We assessed the quality of the evidence using the GRADE approach. Main results Eleven trials including 5662 participants met the inclusion criteria. DOT was performed by a range of people (nurses, community health workers, family members or former TB patients) in a variety of settings (clinic, the patient's home or the home of a community volunteer). DOT versus self-administered Six trials from South Africa, Thailand, Taiwan, Pakistan and Australia compared DOT with self-administered therapy for treatment. Trials included DOT at home by family members, community health workers (who were usually supervised); DOT at home by health staff; and DOT at health facilities. TB cure was low with self-administration across all studies (range 41% to 67%), and direct observation did not substantially improve this (RR 1.08, 95% CI 0.91 to 1.27; five trials, 1645 participants, moderate quality evidence). In a subgroup analysis stratified by the frequency of contact between health services in the self-treatment arm, daily DOT may improve TB cure when compared to self-administered treatment where patients in the self-administered group only visited the clinic every month (RR 1.15, 95% CI 1.06 to 1.25; two trials, 900 participants); but with contact in the control becoming more frequent, this small effect was not apparent (every two weeks: RR 0.96, 95% CI 0.83 to 1.12; one trial, 497 participants; every week: RR 0.90, 95% CI 0.68 to 1.21; two trials, 248 participants). Treatment completion showed a similar pattern, ranging from 59% to 78% in the self-treatment groups, and direct observation did not improve this (RR 1.07, 95% CI 0.96 to 1.19; six trials, 1839 participants, moderate quality evidence). DOT at home versus DOT at health facility In four trials that compared DOT at home by family members, or community health workers, with DOT by health workers at a health facility there was little or no difference in cure or treatment completion (cure: RR 1.02, 95% CI 0.88 to 1.18, four trials, 1556 participants, moderate quality evidence; treatment completion: RR 1.04, 95% CI 0.91 to 1.17, three trials, 1029 participants, moderate quality evidence). DOT by family member versus DOT by community health worker Two trials compared DOT at home by family members with DOT at home by community health workers. There was also little or no difference in cure or treatment completion (cure: RR 1.02, 95% CI 0.86 to 1.21; two trials, 1493 participants, moderate quality evidence; completion: RR 1.05, 95% CI 0.90 to 1.22; two trials, 1493 participants, low quality evidence). Specific patient categories A trial of 300 intravenous drug users in the USA

  1. 30 CFR 1220.011 - Schedule of allowable direct and allocable joint costs and credits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... event of oil spills or other environmental damage are allowable. The costs of actual control and cleanup of oil spills and resulting responsibilities required by applicable laws and regulations are... DETERMINING NET PROFIT SHARE PAYMENT FOR OUTER CONTINENTAL SHELF OIL AND GAS LEASES § 1220.011 Schedule...

  2. Trehalose glycopolymer resists allow direct writing of protein patterns by electron-beam lithography

    NASA Astrophysics Data System (ADS)

    Bat, Erhan; Lee, Juneyoung; Lau, Uland Y.; Maynard, Heather D.

    2015-03-01

    Direct-write patterning of multiple proteins on surfaces is of tremendous interest for a myriad of applications. Precise arrangement of different proteins at increasingly smaller dimensions is a fundamental challenge to apply the materials in tissue engineering, diagnostics, proteomics and biosensors. Herein, we present a new resist that protects proteins during electron-beam exposure and its application in direct-write patterning of multiple proteins. Polymers with pendant trehalose units are shown to effectively crosslink to surfaces as negative resists, while at the same time providing stabilization to proteins during the vacuum and electron-beam irradiation steps. In this manner, arbitrary patterns of several different classes of proteins such as enzymes, growth factors and immunoglobulins are realized. Utilizing the high-precision alignment capability of electron-beam lithography, surfaces with complex patterns of multiple proteins are successfully generated at the micrometre and nanometre scale without requiring cleanroom conditions.

  3. Demonstration of a new technology which allows direct sensor integration on flexible substrates

    NASA Astrophysics Data System (ADS)

    Petropoulos, A.; Goustouridis, D.; Speliotes, T.; Kaltsas, G.

    2009-04-01

    In this work we present a fabrication method for developing thermal sensors on flexible organic substrates. The constructed devices consist of Pt resistors which are directly integrated to the copper tracks of a flexible copper-clad laminate. They reside on top of a 12 ? m thick SU-8 planarization layer, while a sacrificial layer utilized by the negative photoresist ma-N was used in order to define the resistor pattern. The resistors can act as both heating and temperature sensing elements, while due to small thickness and the low thermal conductivity of the Kapton substrate, a very effective thermal isolation is achieved. The minimum radius of curvature of the fabricated devices was found to be 5 mm. As the device is in direct communication to the macrowolrd, the need for wire bonding is eliminated, while the final surface of the produced sensor is relatively planar. The overall process is simple and cost-effective with minimal requirements in fabrication time. The potential application field of the presented devices is considered quite extensive as they can be directly expanded into flexible sensors able to measure quantities such as fluid flow rate, displacement or vacuum.

  4. New directions in childhood obesity research: how a comprehensive biorepository will allow better prediction of outcomes

    PubMed Central

    2010-01-01

    Background Childhood obesity is associated with the early development of diseases such as type 2 diabetes and cardiovascular disease. Unfortunately, to date, traditional methods of research have failed to identify effective prevention and treatment strategies, and large numbers of children and adolescents continue to be at high risk of developing weight-related disease. Aim To establish a unique 'biorepository' of data and biological samples from overweight and obese children, in order to investigate the complex 'gene × environment' interactions that govern disease risk. Methods The 'Childhood Overweight BioRepository of Australia' collects baseline environmental, clinical and anthropometric data, alongside storage of blood samples for genetic, metabolic and hormonal profiles. Opportunities for longitudinal data collection have also been incorporated into the study design. National and international harmonisation of data and sample collection will achieve required statistical power. Results Ethical approval in the parent site has been obtained and early data indicate a high response rate among eligible participants (71%) with a high level of compliance for comprehensive data collection (range 56% to 97% for individual study components). Multi-site ethical approval is now underway. Conclusions In time, it is anticipated that this comprehensive approach to data collection will allow early identification of individuals most susceptible to disease, as well as facilitating refinement of prevention and treatment programs. PMID:20969745

  5. ORIGINAL PAPER Direct Observation of Tribochemically Assisted Wear

    E-print Network

    Marks, Laurence D.

    ORIGINAL PAPER Direct Observation of Tribochemically Assisted Wear on Diamond-Like Carbon Thin direct in situ observation at the nanoscale of tribochemically assisted wear for a tung- sten tip sliding. Differences in the wear directly indicate passivation of the films in hydrogen and accelerated wear in wet

  6. Bacterial RTX Toxins Allow Acute ATP Release from Human Erythrocytes Directly through the Toxin Pore*

    PubMed Central

    Skals, Marianne; Bjaelde, Randi G.; Reinholdt, Jesper; Poulsen, Knud; Vad, Brian S.; Otzen, Daniel E.; Leipziger, Jens; Praetorius, Helle A.

    2014-01-01

    ATP is as an extracellular signaling molecule able to amplify the cell lysis inflicted by certain bacterial toxins including the two RTX toxins ?-hemolysin (HlyA) from Escherichia coli and leukotoxin A (LtxA) from Aggregatibacter actinomycetemcomitans. Inhibition of P2X receptors completely blocks the RTX toxin-induced hemolysis over a larger concentration range. It is, however, at present not known how the ATP that provides the amplification is released from the attacked cells. Here we show that both HlyA and LtxA trigger acute release of ATP from human erythrocytes that preceded and were not caused by cell lysis. This early ATP release did not occur via previously described ATP-release pathways in the erythrocyte. Both HlyA and LtxA were capable of triggering ATP release in the presence of the pannexin 1 blockers carbenoxolone and probenecid, and the HlyA-induced ATP release was found to be similar in erythrocytes from pannexin 1 wild type and knock-out mice. Moreover, the voltage-dependent anion channel antagonist TRO19622 had no effect on ATP release by either of the toxins. Finally, we showed that both HlyA and LtxA were able to release ATP from ATP-loaded lipid (1-palmitoyl-2-oleoyl-phosphatidylcholine) vesicles devoid of any erythrocyte channels or transporters. Again we were able to show that this happened in a non-lytic fashion, using calcein-containing vesicles as controls. These data show that both toxins incorporate into lipid vesicles and allow ATP to be released. We suggest that both toxins cause acute ATP release by letting ATP pass the toxin pores in both human erythrocytes and artificial membranes. PMID:24860098

  7. Supplementary Information for: Direct observation of individual

    E-print Network

    Kowalczykowski, Stephen C.

    nucleation of RecA protein on dsDNA occurs at multiple positions on the nucleic acid lattice, preferentially at regions of high AT sequence content. The binding of up to 4 RecA monomers to the dsDNA does #12 cluster. The length of the observed clusters was determined from the difference of the distances of left

  8. Direct Observation of Paramagnons in Palladium

    SciTech Connect

    Doubble, R.; Hayden, S M.; Dai, Pengcheng; Mook Jr, Herbert A; Thompson, James R; Frost, C.

    2010-01-01

    We report an inelastic neutron scattering study of the spin fluctuations in the nearly ferromagnetic element palladium. Dispersive over-damped collective magnetic excitations or 'paramagnons' are observed up to 128 meV. We analyze our results in terms of a Moriya-Lonzarich-type spin-fluctuation model and estimate the contribution of the spin fluctuations to the low-temperature heat capacity. In spite of the paramagnon excitations being relatively strong, their relaxation rates are large. This leads to a small contribution to the low-temperature electronic specific heat.

  9. Relaxed Observance of Traditional Marriage Rules Allows Social Connectivity without Loss of Genetic Diversity

    PubMed Central

    Guillot, Elsa G.; Hazelton, Martin L.; Karafet, Tatiana M.; Lansing, J. Stephen; Sudoyo, Herawati; Cox, Murray P.

    2015-01-01

    Marriage rules, the community prescriptions that dictate who an individual can or cannot marry, are extremely diverse and universally present in traditional societies. A major focus of research in the early decades of modern anthropology, marriage rules impose social and economic forces that help structure societies and forge connections between them. However, in those early anthropological studies, the biological benefits or disadvantages of marriage rules could not be determined. We revisit this question by applying a novel simulation framework and genome-wide data to explore the effects of Asymmetric Prescriptive Alliance, an elaborate set of marriage rules that has been a focus of research for many anthropologists. Simulations show that strict adherence to these marriage rules reduces genetic diversity on the autosomes, X chromosome and mitochondrial DNA, but relaxed compliance produces genetic diversity similar to random mating. Genome-wide data from the Indonesian community of Rindi, one of the early study populations for Asymmetric Prescriptive Alliance, are more consistent with relaxed compliance than strict adherence. We therefore suggest that, in practice, marriage rules are treated with sufficient flexibility to allow social connectivity without significant degradation of biological diversity. PMID:25968961

  10. 46 CFR 148.03-3 - Direction and observation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Direction and observation. 148.03-3 Section 148.03-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DANGEROUS CARGOES CARRIAGE OF SOLID HAZARDOUS MATERIALS IN BULK Minimum Transportation Requirements § 148.03-3 Direction and observation. Loading or off-loading of a solid...

  11. User's Manual The Virtual Astronaut (VA) is a virtual 3D environment that allows users to observe the Martian

    E-print Network

    1 User's Manual The Virtual Astronaut (VA) is a virtual 3D environment that allows users to observe the Martian landscape and interact with a virtual MER rover. An astronaut can navigate along the surface" key on Mac machines. Fig. 1. Functions of Shortcut Keys (This figure has Windows keyboard. Mac machine

  12. Emerging feed-forward inhibition allows the robust formation of direction selectivity in the developing ferret visual cortex.

    PubMed

    Van Hooser, Stephen D; Escobar, Gina M; Maffei, Arianna; Miller, Paul

    2014-06-01

    The computation of direction selectivity requires that a cell respond to joint spatial and temporal characteristics of the stimulus that cannot be separated into independent components. Direction selectivity in ferret visual cortex is not present at the time of eye opening but instead develops in the days and weeks following eye opening in a process that requires visual experience with moving stimuli. Classic Hebbian or spike timing-dependent modification of excitatory feed-forward synaptic inputs is unable to produce direction-selective cells from unselective or weakly directionally biased initial conditions because inputs eventually grow so strong that they can independently drive cortical neurons, violating the joint spatial-temporal activation requirement. Furthermore, without some form of synaptic competition, cells cannot develop direction selectivity in response to training with bidirectional stimulation, as cells in ferret visual cortex do. We show that imposing a maximum lateral geniculate nucleus (LGN)-to-cortex synaptic weight allows neurons to develop direction-selective responses that maintain the requirement for joint spatial and temporal activation. We demonstrate that a novel form of inhibitory plasticity, postsynaptic activity-dependent long-term potentiation of inhibition (POSD-LTPi), which operates in the developing cortex at the time of eye opening, can provide synaptic competition and enables robust development of direction-selective receptive fields with unidirectional or bidirectional stimulation. We propose a general model of the development of spatiotemporal receptive fields that consists of two phases: an experience-independent establishment of initial biases, followed by an experience-dependent amplification or modification of these biases via correlation-based plasticity of excitatory inputs that compete against gradually increasing feed-forward inhibition. PMID:24598528

  13. Direct observations of field-induced assemblies in magnetite ferrofluids

    NASA Astrophysics Data System (ADS)

    Mousavi, N. S. Susan; Khapli, Sachin D.; Kumar, Sunil

    2015-03-01

    Evolution of microstructures in magnetite-based ferrofluids with weak dipolar moments (particle size ? 10 nm) is studied with an emphasis on examining the effects of particle concentration (?) and magnetic field strength (H) on the structures. Nanoparticles are dispersed in water at three different concentrations, ? = 0.15%, 0.48%, and 0.59% (w/v) [g/ml%] and exposed to uniform magnetic fields in the range of H = 0.05-0.42 T. Cryogenic transmission electron microscopy is employed to provide in-situ observations of the field-induced assemblies in such systems. As the magnetic field increases, the Brownian colloids are observed to form randomly distributed chains aligned in the field direction, followed by head-to-tail chain aggregation and then lateral aggregation of chains termed as zippering. By increasing the field in low concentration samples, the number of chains increases, though their length does not change dramatically. Increasing concentration increases the length of the linear particle assemblies in the presence of a fixed external magnetic field. Thickening of the chains due to zippering is observed at relatively high fields. Through a systematic variation of concentration and magnetic field strength, this study shows that both magnetic field strength and change in concentration can strongly influence formation of microstructures even in weak dipolar systems. Additionally, the results of two commonly used support films on electron microscopy grids, continuous carbon and holey carbon films, are compared. Holey carbon film allows us to create local regions of high concentrations that further assist the development of field-induced assemblies. The experimental observations provide a validation of the zippering effect and can be utilized in the development of models for thermophysical properties such as thermal conductivity.

  14. Direct Observation of Two Proton Radioactivity Using Digital Photography

    SciTech Connect

    Rykaczewski, Krzysztof Piotr; Pfutzner, M.; Dominik, Wojciech; Janas, Z.; Miernik, K.; Bingham, C. R.; Czyrkowski, Henryk; Cwiok, Mikolaj; Darby, Iain; Dabrowski, Ryszard; Ginter, T. N.; Grzywacz, Robert Kazimierz; Karny, M.; Korgul, A.; Kusmierz, Waldemar; Liddick, Sean; Rajabali, Mustafa; Stolz, A.

    2007-01-01

    Recently the observation of a new type of spontaneous radioactive decay has been claimed in which two protons are simultaneously ejected by an atomic nucleus from the ground state1,2,3. Experimental data obtained for the extremely neutron-deficient nuclei 45Fe and 54Zn, were interpreted as the first evidence of such a decay mode which has been sought since 1960.4 However, the technique applied in those studies allowed only measurements of the decay time and the total energy released. Particles emitted in the decay were not identified and the conclusions had to be supported by theoretical arguments. Here we show for the first time, directly and unambiguously, that 45Fe indeed disintegrates by two-proton decay. Furthermore, we demonstrate that the decay branch of this isotope leads to various particle emission channels including two-proton and three-proton emission. To achieve this result we have developed a new type of detector V the Optical Time Projection Chamber (OTPC) in which digital photography is applied to nuclear physics for the first time. The detector records images of tracks from charged particles, allowing for their unambiguous identification and the reconstruction of decay events in three dimensions. This new and simple technique provides a powerful method to identify exotic decay channels involving emission of charged particles. It is expected that further studies with the OTPC device will yield important information on nuclei located at and beyond the proton drip-line, thus providing new material for testing and improving models of very unstable atomic nuclei.

  15. Plasmon Surface Polariton Dispersion by Direct Optical Observation.

    ERIC Educational Resources Information Center

    Swalen, J. D.; And Others

    1980-01-01

    Describes several simple experiments that can be used to observe directly the dispersion curve of plasmon surface polaritons (PSP) on flat metal surfaces. A method is described of observing the increonental change in the wave vector of the PSP due to coatings that differ in thickness by a few nanometers. (Author/CS)

  16. Imaging radar observations of directional properties of ocean waves

    NASA Astrophysics Data System (ADS)

    McLeish, William; Ross, Duncan B.

    1983-05-01

    SEASAT-A synthetic aperture radar (SAR) and side-looking airborne radar (SLAR) images of ocean waves are examined in the form of normalized directional distributions of backscatter variance at series of frequencies. This method provides a more detailed description of radar results than have contoured two-dimensional wave number spectra and reduces some of the uncertainties in relating radar measurements to the waves. The range of aspects of the radar distribution that parallel those of ocean waves is defined. Within this restriction, not only can dominant wave frequencies and directions be determined accurately, but also the shape of a directional peak at a frequency, its directional width, and the background level can be determined approximately. Some of these aspects are examined with SLAR images obtained near reference wave measurements. Through its superior directional resolution, the radar appears to have distinguished two wave trains at a single frequency only 20° different in direction. The SEASAT-A satellite SAR provided an unusual opportunity to examine directional properties of waves in the hostile environment about Hurricane Fico. A swell highly dispersed in frequency and direction at a distance from the center of 450 km had a minimum observed directional width of 11°. Wave directions, their changes with frequency, and directional widths were in accord with those expected from the hurricane winds. Thematic maps of the direction and width of the swell energy as it spread across the ocean surface show smooth changes in these properties over distance, with relatively small scatter of individual values. These patterns also are in accord with those from a simple hurricane wave emission concept, but details of the distributions show distinct departures that must represent unrecognized smaller-scale fluctuations of the process.

  17. The Behavior Observation Instrument: a method of direct observation for program evaluation.

    PubMed Central

    Alevizos, P; DeRisi, W; Liberman, R; Eckman, T; Callahan, E

    1978-01-01

    The background and development of a multicategory direct observation system, the Behavior Observation Instrument (BOI), is described. This time-sampling procedure for recording the behavior of persons is demonstrated in several treatment settings and the results applied to issues of program evaluation. Elements that have prevented direct observation from being widely adopted, such as costs, manpower, and training requirements, are systematically analyzed. A basic psychometric analysis of the instrument is used to determine optimum frequency and duration of observation intervals as well as observer agreement. The results imply that direct observation methods, once assumed by some to belong to the special province of the single-subject design, can be used to assess the effects of programs on groups of psychiatric clients in an efficient and economic manner. PMID:97258

  18. Direct Observation of Nanoscale Switching Centers in Metal/Molecule/

    E-print Network

    Bockrath, Marc

    , with zero-bias resistance typically >105 . The devices can be switched reVersibly and repeatedly to higherDirect Observation of Nanoscale Switching Centers in Metal/Molecule/ Metal Structures Chun Ning Lau switching in metal/molecule/metal structures has attracted tremendous and broad interest. Understanding

  19. Quantifying predation on soybean aphid through direct field observations

    E-print Network

    Landis, Doug

    Quantifying predation on soybean aphid through direct field observations Alejandro C. Costamagna Received 8 August 2006; accepted 5 April 2007 Available online 12 April 2007 Abstract The soybean aphid. glycines populations using predator exclusion cages and correlating predator and aphid abundances. However

  20. New Directions: Emerging Satellite Observations of Above-cloud Aerosols and Direct Radiative Forcing

    NASA Technical Reports Server (NTRS)

    Yu, Hongbin; Zhang, Zhibo

    2013-01-01

    Spaceborne lidar and passive sensors with multi-wavelength and polarization capabilities onboard the A-Train provide unprecedented opportunities of observing above-cloud aerosols and direct radiative forcing. Significant progress has been made in recent years in exploring these new aerosol remote sensing capabilities and generating unique datasets. The emerging observations will advance the understanding of aerosol climate forcing.

  1. Scheme for directly observing the noncommutativity of the position and the momentum operators with interference

    NASA Astrophysics Data System (ADS)

    Lee, Jong-Chan; Kim, Yong-Su; Ra, Young-Sik; Lim, Hyang-Tag; Kim, Yoon-Ho

    2012-10-01

    Although noncommutativity of a certain set of quantum operators (e.g., creation and annihilation operators and Pauli spin operators) has been shown experimentally in recent years, the commutation relation for the position and the momentum operators has not been directly demonstrated to date. In this paper we propose and analyze an experimental scheme for directly observing the noncommutativity of the position and the momentum operators using single-photon quantum interference. While the scheme is studied for the single-photon state as the input quantum state, the analysis applies equally to matter-wave interference, allowing a direct test of the position-momentum commutation relation with a massive particle.

  2. Direct observation of polymer dynamics in semi-dilute solutions

    NASA Astrophysics Data System (ADS)

    Hsiao, Kai-Wen; Brockman, Christopher; Schroeder, Charles M.

    2014-03-01

    In this work, we use single molecule techniques to study polymer dynamics in semi-dilute solutions. Here, we study the steady state extension and relaxation time dynamics of polymer molecules in semi-dilute DNA solutions in extensional flow. Polymer chain dynamics are complicated in semi-dilute solutions due to chain overlap, hydrodynamic interactions, and excluded volume interactions. We use single molecule fluorescence microscopy and a microfluidic-based hydrodynamic trap to directly observe the dynamics of polymers in non-dilute solutions. We report the scaling of polymer relaxation time as a function of polymer concentration, and we observe a crossover in chain behavior from the dilute to semi-dilute regime. Interestingly, we observe a pronounced center-of-mass drift of single polymer chains in directions orthogonal to flow in semi-dilute solutions, which is characterized as a function of concentration and flow rate. By using the automated hydrodynamic trap coupled with a piezoelectric stage, we are able to track the 3-D position of single polymer molecules and deduce the relationship between strain rate and polymer extension. Overall, our work reports on a key advance in the field of polymer dynamics via direct observation of dynamics in semi-dilute solutions in strong flows

  3. Setting up a direct debit with GoCardless Please note that registering in this way allows you to set up an individual user account with

    E-print Network

    Setting up a direct debit with GoCardless Please note that registering in this way allows you to set up an individual user account with GoCardless where you can manage your direct debit payments to the LMS, including changing your bank details. The following is a step-by-step guide on setting up

  4. Microcrack closure in rocks under stress - Direct observation

    NASA Technical Reports Server (NTRS)

    Batzle, M. L.; Simmons, G.; Siegfried, R. W.

    1980-01-01

    Direct observations of the closure of microcracks in rocks under increasing stress are reported. Uniaxial stresses up to 300 bars were applied to untreated and previously heated samples of Westerly granite and Frederick diabase by a small hydraulic press which fit entirely within a scanning electron microscope. Crack closure characteristics are found to depend on crack orientation, with cracks perpendicular to the applied stress closing and those parallel tending to open, as well as crack aspect ratio, crack intersection properties, stress concentrations and surface roughness. Uniaxial and hydrostatic stress measurements are found to be strongly dependent on fracture content as observed by SEM, and the observed hysteresis in strain measurements in the first stress cycles is also related to microscopic processes

  5. Abstract--Remotely operated crawlers are specialized vehicles that allow for underwater intervention by staying in direct

    E-print Network

    Wood, Stephen L.

    operated vehicle crawler for multiple research activities such as underwater archaeology documentation -- Remotely Operated Vehicle, ROV, Remotely Operated Crawler, Robotics, Underwater Archaeology, Marine1 Abstract-- Remotely operated crawlers are specialized vehicles that allow for underwater

  6. Direct observation of Kelvin waves excited by quantized vortex reconnection

    PubMed Central

    Fonda, Enrico; Meichle, David P.; Ouellette, Nicholas T.; Hormoz, Sahand; Lathrop, Daniel P.

    2014-01-01

    Quantized vortices are key features of quantum fluids such as superfluid helium and Bose–Einstein condensates. The reconnection of quantized vortices and subsequent emission of Kelvin waves along the vortices are thought to be central to dissipation in such systems. By visualizing the motion of submicron particles dispersed in superfluid 4He, we have directly observed the emission of Kelvin waves from quantized vortex reconnection. We characterize one event in detail, using dimensionless similarity coordinates, and compare it with several theories. Finally, we give evidence for other examples of wavelike behavior in our system. PMID:24704878

  7. Direct observation of thermal relaxation in artificial spin ice.

    PubMed

    Farhan, A; Derlet, P M; Kleibert, A; Balan, A; Chopdekar, R V; Wyss, M; Perron, J; Scholl, A; Nolting, F; Heyderman, L J

    2013-08-01

    We study the thermal relaxation of artificial spin ice with photoemission electron microscopy, and are able to directly observe how such a system finds its way from an energetically excited state to the ground state. On plotting vertex-type populations as a function of time, we can characterize the relaxation, which occurs in two stages, namely a string and a domain regime. Kinetic Monte Carlo simulations agree well with the temporal evolution of the magnetic state when including disorder, and the experimental results can be explained by considering the effective interaction energy associated with the separation of pairs of vertex excitations. PMID:23952441

  8. Direct observation of Kelvin waves excited by quantized vortex reconnection.

    PubMed

    Fonda, Enrico; Meichle, David P; Ouellette, Nicholas T; Hormoz, Sahand; Lathrop, Daniel P

    2014-03-25

    Quantized vortices are key features of quantum fluids such as superfluid helium and Bose-Einstein condensates. The reconnection of quantized vortices and subsequent emission of Kelvin waves along the vortices are thought to be central to dissipation in such systems. By visualizing the motion of submicron particles dispersed in superfluid (4)He, we have directly observed the emission of Kelvin waves from quantized vortex reconnection. We characterize one event in detail, using dimensionless similarity coordinates, and compare it with several theories. Finally, we give evidence for other examples of wavelike behavior in our system. PMID:24704878

  9. Direct observations of the evolution of polar cap ionization patches.

    PubMed

    Zhang, Qing-He; Zhang, Bei-Chen; Lockwood, Michael; Hu, Hong-Qiao; Moen, Jøran; Ruohoniemi, J Michael; Thomas, Evan G; Zhang, Shun-Rong; Yang, Hui-Gen; Liu, Rui-Yuan; McWilliams, Kathryn A; Baker, Joseph B H

    2013-03-29

    Patches of ionization are common in the polar ionosphere, where their motion and associated density gradients give variable disturbances to high-frequency (HF) radio communications, over-the-horizon radar location errors, and disruption and errors to satellite navigation and communication. Their formation and evolution are poorly understood, particularly under disturbed space weather conditions. We report direct observations of the full evolution of patches during a geomagnetic storm, including formation, polar cap entry, transpolar evolution, polar cap exit, and sunward return flow. Our observations show that modulation of nightside reconnection in the substorm cycle of the magnetosphere helps form the gaps between patches where steady convection would give a "tongue" of ionization (TOI). PMID:23539601

  10. Direct observation of thitherto unobservable quantum phenomena by using electrons

    PubMed Central

    Tonomura, Akira

    2005-01-01

    Fundamental aspects of quantum mechanics, which were discussed only theoretically as “thought experiments” in the 1920s and 1930s, have begun to frequently show up in nanoscopic regions owing to recent rapid progress in advanced technologies. Quantum phenomena were once regarded as the ultimate factors limiting further miniaturization trends of microstructured electronic devices, but now they have begun to be actively used as the principles for new devices such as quantum computers. To directly observe what had been unobservable quantum phenomena, we have tried to develop bright and monochromatic electron beams for the last 35 years. Every time the brightness of an electron beam improved, fundamental experiments in quantum mechanics became possible, and quantum phenomena became observable by using the wave nature of electrons. PMID:16150719

  11. Directly observable optical properties of sprites in Central Europe

    NASA Astrophysics Data System (ADS)

    Bór, József

    2013-04-01

    Luminous optical emissions accompanying streamer-based natural electric breakdown processes initiating in the mesosphere are called sprites. 489 sprite events have been observed with a TV frame rate video system in Central Europe from Sopron (47.68N, 16.58E, 230 m MSL), Hungary between 2007 and 2009. On the basis of these observations, characteristic morphological properties of sprites, i.e. basic forms (e.g. column, carrot, angel, etc.) as well as common morphological features (e.g. tendrils, glows, puffs, beads, etc.), have been identified. Probable time sequences of streamer propagation directions were associated with each of the basic sprite forms. It is speculated that different sequences of streamer propagation directions can result in very similar final sprite shapes. The number and type variety of sprite elements appearing in an event as well as the total optical duration of an event was analyzed statistically. Jellyfish and dancing sprite events were considered as special subsets of sprite clusters. It was found that more than 90% of the recorded sprite elements appeared in clusters rather than alone and more than half of the clusters contained more than one basic sprite forms. The analysis showed that jellyfish sprites and clusters of column sprites featuring glows and tendrils do not tend to have optical lifetimes longer than 80 ms. Such very long optical lifetimes have not been observed in sprite clusters containing more than 25 elements of any type, either. In contrast to clusters containing sprite entities of only one form, sprite events showing more sprite forms seem to have extended optical durations more likely. The need for further investigation and for finding theoretical concepts to link these observations to electric conditions ambient for sprite formation is emphasized.

  12. Direct observation of photoinduced bent nitrosyl excited-state complexes

    SciTech Connect

    Sawyer, Karma R.; Steele, Ryan P.; Glascoe, Elizabeth A.; Cahoon, James F.; Schlegel, Jacob P.; Head-Gordon, Martin; Harris, Charles B.

    2008-06-28

    Ground state structures with side-on nitrosyl ({eta}{sup 2}-NO) and isonitrosyl (ON) ligands have been observed in a variety of transition-metal complexes. In contrast, excited state structures with bent-NO ligands have been proposed for years but never directly observed. Here we use picosecond time-resolved infrared spectroscopy and density functional theory (DFT) modeling to study the photochemistry of Co(CO){sub 3}(NO), a model transition-metal-NO compound. Surprisingly, we have observed no evidence for ON and {eta}{sup 2}-NO structural isomers, but have observed two bent-NO complexes. DFT modeling of the ground and excited state potentials indicates that the bent-NO complexes correspond to triplet excited states. Photolysis of Co(CO){sub 3}(NO) with a 400-nm pump pulse leads to population of a manifold of excited states which decay to form an excited state triplet bent-NO complex within 1 ps. This structure relaxes to the ground triplet state in ca. 350 ps to form a second bent-NO structure.

  13. Fostering directly observed treatment in tuberculosis: a program manager's perspective.

    PubMed

    Shrivastava, Saurabh Rambiharilal; Shrivastava, Prateek Saurabh; Ramasamy, Jegadeesh

    2014-01-01

    Global Tuberculosis (TB) report (2013) has revealed that an estimated 8.6 million people developed TB of which, India accounts for almost 26% of the cases. These estimates clearly suggest that the country's efforts to achieve Millennium Development Goal 6 by 2015 have not delivered the desired output. In India, the TB prevention and control activities are supervised and implemented under the Revised National TB Control Program (RNTCP), which recognizes that implementation of a good quality Directly Observed Treatment with Short course chemotherapy (DOTS) is the first priority for TB control. Directly Observed Treatment (DOT) is the key element in DOTS strategy, in which a DOT provider insures and supports the patients in consuming their drugs throughout the course of treatment. In order to meet the country's vision to achieve universal access of TB care, the RNTCP has launched a "treatment adherence scheme" (public-private partnership scheme). Further, an evidence-based integrated strategy should be formulated for addressing the identified barriers which advocates universal administration of DOT. To conclude, DOT in RNTCP insures long-term adherence to the treatment, with right drugs in right doses, at right intervals and thus plays an indispensable role in improving the outcome indicators of the program and the quality of life in patients. PMID:24596899

  14. Direct Observation Assessment of Milestones: Problems with Reliability

    PubMed Central

    Schott, Meghan; Kedia, Raashee; Promes, Susan B.; Swoboda, Thomas; O’Rourke, Kevin; Green, Walter; Liu, Rachel; Stansfield, Brent; Santen, Sally A.

    2015-01-01

    Introduction Emergency medicine (EM) milestones are used to assess residents’ progress. While some milestone validity evidence exists, there is a lack of standardized tools available to reliably assess residents. Inherent to this is a concern that we may not be truly measuring what we intend to assess. The purpose of this study was to design a direct observation milestone assessment instrument supported by validity and reliability evidence. In addition, such a tool would further lend validity evidence to the EM milestones by demonstrating their accurate measurement. Methods This was a multi-center, prospective, observational validity study conducted at eight institutions. The Critical Care Direct Observation Tool (CDOT) was created to assess EM residents during resuscitations. This tool was designed using a modified Delphi method focused on content, response process, and internal structure validity. Paying special attention to content validity, the CDOT was developed by an expert panel, maintaining the use of the EM milestone wording. We built response process and internal consistency by piloting and revising the instrument. Raters were faculty who routinely assess residents on the milestones. A brief training video on utilization of the instrument was completed by all. Raters used the CDOT to assess simulated videos of three residents at different stages of training in a critical care scenario. We measured reliability using Fleiss’ kappa and interclass correlations. Results Two versions of the CDOT were used: one used the milestone levels as global rating scales with anchors, and the second reflected a current trend of a checklist response system. Although the raters who used the CDOT routinely rate residents in their practice, they did not score the residents’ performances in the videos comparably, which led to poor reliability. The Fleiss’ kappa of each of the items measured on both versions of the CDOT was near zero. Conclusion The validity and reliability of the current EM milestone assessment tools have yet to be determined. This study is a rigorous attempt to collect validity evidence in the development of a direct observation assessment instrument. However, despite strict attention to validity evidence, inter-rater reliability was low. The potential sources of reducible variance include rater- and instrument-based error. Based on this study, there may be concerns for the reliability of other EM milestone assessment tools that are currently in use. PMID:26594281

  15. Responses to the advanced notice of proposed rulemaking EPA published on June 6, 1996 regarding changes to the EPA allowance auctions and elimination of the direct sale

    SciTech Connect

    Critchfield, L.R.

    1997-12-31

    On June 6, 1996, EPA`s Acid Rain Program published an advance notice of proposed rulemaking (ANPRM) in the Federal Register seeking comment on: (1) whether to change the design of the annual sulfur dioxide (SO{sub 2}) allowance auctions; (2) whether to change the timing of the allowance auctions; (3) whether to change the requirement that the minimum price of offered allowances must be in whole dollars, and (4) whether EPA should propose the ability to submit allowance transfers electronically. EPA also published on that day a proposed and direct final rule on whether to eliminate the direct sale. This paper documents the issues addressed in the ANPRM, the comments EPA received, and EPA`s responses to those comments. EPA received comments from 14 separate commenters.

  16. Direct observation of the strange b baryon Xib-.

    PubMed

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Assis Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Banerjee, P; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chan, K; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clément, C; Clément, B; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, S J; de Jong, P; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, J; Guo, F; Gutierrez, P; Gutierrez, G; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J R; Kalk, J M; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kothari, B; Kozelov, A V; Krop, D; Kryemadhi, A; Kuhl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lazoflores, J; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lellouch, J; Lesne, V; Leveque, J; Lewis, P; Li, J; Li, Q Z; Li, L; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendes, A; Mendoza, L; Mercadante, P G; Merekov, Y P; Merkin, M; Merritt, K W; Meyer, J; Meyer, A; Michaut, M; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padley, P; Pangilinan, M; Panov, G; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perea, P M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M

    2007-08-01

    We report the first direct observation of the strange b baryon Xi(b)- (Xi(b)+). We reconstruct the decay Xi(b)- -->J/psiXi-, with J/psi-->mu+mu-, and Xi--->Lambdapi--->ppi-pi- in pp collisions at square root of s =1.96 TeV. Using 1.3 fb(-1) of data collected by the D0 detector, we observe 15.2 +/- 4.4(stat)(-0.4)(+1.9)(syst) Xi(b)- candidates at a mass of 5.774 +/- 0.011(stat) +/- 0.015(syst) GeV. The significance of the observed signal is 5.5 sigma, equivalent to a probability of 3.3 x 10(-8) of it arising from a background fluctuation. Normalizing to the decay Lambda(b)-->J/psiLambda, we measure the relative rate sigma(Xi(b-) x B(Xi)b})- -->J/psiXi-)/sigma(Lambda(b)) x B(Lambda(b)-->J/psiLambda) = 0.28+/-0.09(stat)(-0.08)(+0.09)(syst). PMID:17930744

  17. An Earth-Directed CME not Observed in LASCO Images

    NASA Astrophysics Data System (ADS)

    Yashiro, S.; Gopalswamy, N.; Akiyama, S.

    2010-12-01

    The COR1 coronagraphs on STEREO-A and -B observed an Earth-directed CME originating from N09W15 at 02:20 UT on 2010/07/09. The apparent CME speed is only 291 km/s, and the angular width is 60 degrees. The CME is somewhat slower than the average LASCO CME (average speed ~450 km/s) but not narrow. The CME was expected to be seen as a halo CME because of the geometry and large width. However, the CME could not be identified in the LASCO running difference movie because of the visibility of the white-light coronagraph. On the other hand, EUV images taken by SDO/AIA show a clear dimming to the northwest of the source region and a wave-like feature propagating to the east. Faint Earth-directed CMEs, seem to be better indicated by surface eruptive signatures such as dimming and EUV waves. We discuss how to estimate CME parameters using the EUV data alone.

  18. Femtosecond direct observation of charge transfer between bases in DNA

    PubMed Central

    Wan, Chaozhi; Fiebig, Torsten; Schiemann, Olav; Barton, Jacqueline K.; Zewail, Ahmed H.

    2000-01-01

    Charge transfer in supramolecular assemblies of DNA is unique because of the notion that the ?-stacked bases within the duplex may mediate the transport, possibly leading to damage and/or repair. The phenomenon of transport through ?-stacked arrays over a long distance has an analogy to conduction in molecular electronics, but the mechanism still needs to be determined. To decipher the elementary steps and the mechanism, one has to directly measure the dynamics in real time and in suitably designed, structurally well characterized DNA assemblies. Here, we report our first observation of the femtosecond dynamics of charge transport processes occurring between bases within duplex DNA. By monitoring the population of an initially excited 2-aminopurine, an isomer of adenine, we can follow the charge transfer process and measure its rate. We then study the effect of different bases next to the donor (acceptor), the base sequence, and the distance dependence between the donor and acceptor. We find that the charge injection to a nearest neighbor base is crucial and the time scale is vastly different: 10 ps for guanine and up to 512 ps for inosine. Depending on the base sequence the transfer can be slowed down or inhibited, and the distance dependence is dramatic over the range of 14 ?. These observations provide the time scale, and the range and efficiency of the transfer. The results suggest the invalidity of an efficient wire-type behavior and indicate that long-range transport is a slow process of a different mechanism. PMID:11106376

  19. Direct observation of solidification microstructures around absolute stability

    SciTech Connect

    Ludwig, A.; Kurz, W.

    1996-09-01

    This paper presents, for the first time, experimental evidence for absolute stability in a transparent alloy. The succinonitrile-argon system was used to investigate the morphological transition from a cellular to a planar solid-liquid interface at high solidification velocities. Directional solidification of the organic contained in thin capillary tubes was observed in situ with an optical microscope. At the maximum interface velocity of 1.5 mm/s, a reduction of the solute content of the alloy resulted in a morphological transition from a cellular to a planar growth front. This transition developed in three stages: (1) transition from deep cylindrical cells to mixed patterns of cylindrical and elongated cells; (ii) transition from cylindrical and elongated cells to low amplitude cells; (iii) transition from low amplitude cells to plane front. Within the limits of uncertainties with respect to the material properties and the thermal gradient, correspondence between the experimental results on plane front transition and linear stability theory exists. It is shown that the transitions observed are located in the region near the limit point of the neutral stability curve on the branch for absolute morphological stability.

  20. Direct observation of liquid-like behavior of a single Au grain boundary

    NASA Astrophysics Data System (ADS)

    Casillas, Gilberto; Ponce, Arturo; Velázquez-Salazar, J. Jesús; José-Yacamán, Miguel

    2013-06-01

    Behavior of matter at the nanoscale differs from that of the bulk due to confinement and surface effects. Here, we report a direct observation of liquid-like behavior of a single grain boundary formed by cold-welding Au nanoparticles, 40 nm in size, by mechanical manipulation in situ TEM. The grain boundary rotates almost freely due to the free surfaces and can rotate about 90 degrees. The grain boundary sustains more stress than the bulk, confirming a strong bonding between the nanoparticles. Moreover, this technique allows the measurement of the surface diffusion coefficient from experimental observations, which we compute for the Au nanoparticles. This methodology can be used for any metal, oxide, semiconductor or combination of them.Behavior of matter at the nanoscale differs from that of the bulk due to confinement and surface effects. Here, we report a direct observation of liquid-like behavior of a single grain boundary formed by cold-welding Au nanoparticles, 40 nm in size, by mechanical manipulation in situ TEM. The grain boundary rotates almost freely due to the free surfaces and can rotate about 90 degrees. The grain boundary sustains more stress than the bulk, confirming a strong bonding between the nanoparticles. Moreover, this technique allows the measurement of the surface diffusion coefficient from experimental observations, which we compute for the Au nanoparticles. This methodology can be used for any metal, oxide, semiconductor or combination of them. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr01501g

  1. Directly Observed Therapy and Improved Tuberculosis Treatment Outcomes in Thailand

    PubMed Central

    Anuwatnonthakate, Amornrat; Limsomboon, Pranom; Nateniyom, Sriprapa; Wattanaamornkiat, Wanpen; Komsakorn, Sittijate; Moolphate, Saiyud; Chiengsorn, Navarat; Kaewsa-ard, Samroui; Sombat, Potjaman; Siangphoe, Umaporn; Mock, Philip A.; Varma, Jay K.

    2008-01-01

    Background The World Health Organization (WHO) recommends that tuberculosis (TB) patients receive directly observed therapy (DOT). Randomized controlled trials have not consistently shown that this practice improves TB treatment success rates. In Thailand, one of 22 WHO-designated high burden TB countries, patients may have TB treatment observed by a health care worker (HCW), family member, or no one. We studied whether DOT improved TB treatment outcomes in a prospective, observational cohort. Methods and Findings We prospectively collected epidemiologic data about TB patients treated at public and private facilities in four provinces in Thailand and the national infectious diseases hospital from 2004–2006. Public health staff recorded the type of observed therapy that patients received during the first two months of TB treatment. We limited our analysis to pulmonary TB patients never previously treated for TB and not known to have multidrug-resistant TB. We analyzed the proportion of patients still on treatment at the end of two months and with treatment success at the end of treatment according to DOT type. We used propensity score analysis to control for factors associated with DOT and treatment outcome. Of 8,031 patients eligible for analysis, 24% received HCW DOT, 59% family DOT, and 18% self-administered therapy (SAT). Smear-positive TB was diagnosed in 63%, and 21% were HIV-infected. Of patients either on treatment or that defaulted at two months, 1601/1636 (98%) patients that received HCW DOT remained on treatment at two months compared with 1096/1268 (86%) patients that received SAT (adjusted OR [aOR] 3.8; 95% confidence interval [CI] 2.4–6.0) and 3782/3987 (95%) patients that received family DOT (aOR 2.1; CI, 1.4–3.1). Of patients that had treatment success or that defaulted at the end of treatment, 1369/1477 (93%) patients that received HCW DOT completed treatment compared with 744/1074 (69%) patients that received SAT (aOR 3.3; CI, 2.4–4.5) and 3130/3529 (89%) patients that received family DOT (aOR 1.5; 1.2–1.9). The benefit of HCW DOT compared with SAT was similar, but smaller, when comparing patients with treatment success to those with death, default, or failure. Conclusions In Thailand, two months of DOT was associated with lower odds of default during treatment. The magnitude of benefit was greater for DOT provided by a HCW compared with a family member. Thailand should consider increasing its use of HCW DOT during TB treatment. PMID:18769479

  2. Microcrack closure in rocks under stress: direct observation

    SciTech Connect

    Batzle, M.L.; Simmons, G.; Siegfried, R.W.

    1980-12-10

    Microcrack closure in rocks under increasing stress was observed directly with a scanning electron microscope. Uniaxial stresses to 300 bars were applied with a small hydraulic press to specimens of Westerly (RI) granite, both unheated and previously heat cycled to 500/sup 0/C, and of Frederick (MD) diabase, heat cycled to 700/sup 0/C. Closure characteristics (rate, final closure pressure, etc.) depend on crack orientation, shape, surface roughness, and on the nature of fracture intersections and interactions. Cracks perpendicular to the applied stress closed while those parallel to the stress tended to open. Long, narrow cracks (low aspect ratio) closed at relatively low pressures. At some intersections, one fracture would open while another simultaneously closed, depending upon their orientations. Many fractures closed uniformly even though offset by other fractures. Local stress concentrations often caused new fracturing at low applied stress. Some fractures were propped open until material lodged inside was crushed. Significant irreversible damage occurred during the first stress cycle. Closure characteristics varied significantly among the samples. The unheated granite has cracks with rough, pitted, and mismatched walls. Only partial closure occurred under stress with many sections remaining open. Crack porosity is reduced but continues to be interconnected. Fractures in the preheated granite and diabase are also irregular, but the walls are well-matched and closure is nearly complete. The cracks in the heated granite closed at lower stresses than in the diabase. As the maximum stress was approached for the heated granite, new transgranular cracks formed and preexisting cracks were enlarged. The variations in closure rate and character were also observed in strain measurements.

  3. Direct observation of symmetry-specific precession in a ferrimagnet

    NASA Astrophysics Data System (ADS)

    Warnicke, P.; Stavitski, E.; Lee, J.-S.; Yang, A.; Chen, Z.; Zuo, X.; Zohar, S.; Bailey, W. E.; Harris, V. G.; Arena, D. A.

    2015-09-01

    Here we demonstrate an experimental observation of GHz-scale spin dynamics resolved to sublattice octahedral (Oh) tetrahedral (Td) sites in a spinel ferrimagnet, in this case a Mn-ferrite thin film. X-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) are used, in combination with multiplet calculations, to uniquely identify the spectral signature from Mn2 + and Fe2 +,3 + on Oh and Td lattice sites. With the sample under rf excitation, the spin alignment of the sublattices is tracked with time-resolved XMCD (TR-XMCD). The spin alignment of the sublattices is mostly antiferromagnetic. The phase difference between the Oh Fe2 + [Oh Fe3 +] and Td Mn2 + sites is 181.2 ±3 .8? [183 .3?±3 .7? ] at 150 K and 186.6 ±2 .2? [182 .0?±2 .2? ] at 300 K. Such direct measurement of the dynamic coupling, exchange stiffness, and damping enabled by TR-XMCD across sublattices will be essential for optimizing the development of future-generation microwave devices.

  4. Method for observing phase objects without halos and directional shadows

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshimasa; Kajitani, Kazuo; Ohde, Hisashi

    2015-03-01

    A new microscopy method for observing phase objects without halos and directional shadows is proposed. The key optical element is an annular aperture at the front focal plane of a condenser with a larger diameter than those used in standard phase contrast microscopy. The light flux passing through the annular aperture is changed by the specimen's surface profile and then passes through an objective and contributes to image formation. This paper presents essential conditions for realizing the method. In this paper, images of colonies formed by induced pluripotent stem (iPS) cells using this method are compared with the conventional phase contrast method and the bright-field method when the NA of the illumination is small to identify differences among these techniques. The outlines of the iPS cells are clearly visible with this method, whereas they are not clearly visible due to halos when using the phase contrast method or due to weak contrast when using the bright-field method. Other images using this method are also presented to demonstrate a capacity of this method: a mouse ovum and superimposition of several different images of mouse iPS cells.

  5. Direct observation of SU(N) orbital magnetism

    E-print Network

    Zhang, X; Bromley, S L; Kraus, C V; Safronova, M S; Zoller, P; Rey, A M; Ye, J

    2014-01-01

    Symmetries play a fundamental role in the laws of nature. SU(N) symmetry can emerge in a quantum system with N single-particle spin states when the spin degree of freedom is decoupled from interactions. Such a system is anticipated to exhibit large degeneracy and exotic many-body behaviors. Owing to the strong decoupling between electronic-orbital and nuclear-spin degrees of freedom, alkaline-earth atoms (AEAs), prepared in the two lowest electronic states (clock states), are predicted to obey an accurate SU(N=2I+1) symmetry arising from the nuclear spin (I). So far, only indirect evidence for this symmetry exists, and the scattering parameters remain largely unknown. Here we report the first direct observation of SU(N=10) symmetry in 87Sr (I=9/2) using the state-of-the-art measurement precision offered by an ultra-stable laser. By encoding the electronic orbital degree of freedom in the two clock states, while keeping the system open to all 10 nuclear spin sublevels, we probe the non-equilibrium two-orbital ...

  6. Direct observation of interface instability during crystal growth

    NASA Technical Reports Server (NTRS)

    Tiller, W. A.; Feigelson, R. S.; Elwell, D.

    1982-01-01

    The general aim of this investigation was to study interface stability and solute segregation phenomena during crystallization of a model system. Emphasis was to be placed on direct observational studies partly because this offered the possibility at a later stage of performing related experiments under substantially convection-free conditions in the space shuttle. The major achievements described in this report are: (1) the development of a new model system for fundamental studies of crystal growth from the melt and the measurement of a range of material parameters necessary for comparison of experiment with theory. (2) The introduction of a new method of measuring segregation coefficient using absorption of a laser beam by the liquid phase. (3) The comparison of segregation in crystals grown by gradient freezing and by pulling from the melt. (4) The introduction into the theory of solute segregation of an interface field term and comparison with experiment. (5) The introduction of the interface field term into the theories of constitutional supercooling and morphological stability and assessment of its importance.

  7. Direct Observation of the Controlled Magnetization Reversal Processes in Py/Al/Py Assymmetric Ring Stacks

    SciTech Connect

    Huang, L.; Schofield, M.A.; Zhu, Y.

    2009-07-27

    Electron holographic experiments were performed to study the magnetization reversal process of patterned Py/Al/Py (20nm/20nm/10nm) asymmetric ring stacks. By changing the in-plane field applied perpendicular to the ring's symmetric axis, we directly observed the vortex-based magnetization reversal process through controlled domain wall motion and annihilation. The two magnetic layers were found to switch at different critical fields, leading to the existence of various distinct domain state combinations. Quantitative agreement was obtained between measured phase shifts and those derived from micromagnetic calculations, which allows us to resolve the layer-by-layer magnetic behavior as a function of applied external field.

  8. Tracking individual membrane proteins and their biochemistry: The power of direct observation.

    PubMed

    Barden, Adam O; Goler, Adam S; Humphreys, Sara C; Tabatabaei, Samaneh; Lochner, Martin; Ruepp, Marc-David; Jack, Thomas; Simonin, Jonathan; Thompson, Andrew J; Jones, Jeffrey P; Brozik, James A

    2015-11-01

    The advent of single molecule fluorescence microscopy has allowed experimental molecular biophysics and biochemistry to transcend traditional ensemble measurements, where the behavior of individual proteins could not be precisely sampled. The recent explosion in popularity of new super-resolution and super-localization techniques coupled with technical advances in optical designs and fast highly sensitive cameras with single photon sensitivity and millisecond time resolution have made it possible to track key motions, reactions, and interactions of individual proteins with high temporal resolution and spatial resolution well beyond the diffraction limit. Within the purview of membrane proteins and ligand gated ion channels (LGICs), these outstanding advances in single molecule microscopy allow for the direct observation of discrete biochemical states and their fluctuation dynamics. Such observations are fundamentally important for understanding molecular-level mechanisms governing these systems. Examples reviewed here include the effects of allostery on the stoichiometry of ligand binding in the presence of fluorescent ligands; the observation of subdomain partitioning of membrane proteins due to microenvironment effects; and the use of single particle tracking experiments to elucidate characteristics of membrane protein diffusion and the direct measurement of thermodynamic properties, which govern the free energy landscape of protein dimerization. The review of such characteristic topics represents a snapshot of efforts to push the boundaries of fluorescence microscopy of membrane proteins to the absolute limit. This article is part of the Special Issue entitled 'Fluorescent Tools in Neuropharmacology'. PMID:25998277

  9. Degassing-induced crystallization in basalts: direct experimental observations

    NASA Astrophysics Data System (ADS)

    Applegarth, L. J.; Tuffen, H.; James, M. R.; Cashman, K.; Pinkerton, H.

    2012-12-01

    Degassing of magma increases its liquidus temperature and can thus trigger crystal growth. This can drastically increase magma viscosity and exert a key control on eruptive dynamics in a range of magma compositions. To investigate the process we have used a microscope and heated stage to obtain the first direct observations of degassing-driven crystal growth in natural basaltic melts at magmatic temperatures. We heated samples from Mt. Etna, Italy (0.39 wt.% H2O), and Kilauea, Hawaii (0.18 wt.% H2O) in air at atmospheric pressure to temperatures between 1190 and 1270 °C. Samples were held isothermally for 0.5 to 17 hours before cooling to sub-solidus temperatures. Bubble growth above 900 °C indicated volatile exsolution during heating. Isothermal conditions produced numerous new plagioclase crystals in the Etna sample, which grew to ?160 ?m at maximum rates of 5.2 x 10-6 to 1.8 x 10-5 cm s-1. The dwell temperature determined both crystal growth rates and morphologies (tabular to spherulitic). As equilibrium was approached after 20 minutes crystal growth slowed dramatically. Few new crystals appeared in the H2O-poor Kilauea sample, and maximum growth rates of 1.7 to 6.5 x 10-6 cm s-1 were determined. Pre-existing crystal textures strongly influenced crystal nucleation and growth during cooling, which highlights the importance of studying natural rather than experimental samples. Our results indicate that, when melts are sufficiently H2O-rich, degassing can indeed trigger rapid crystal growth. The resultant changes in the texture, and hence rheology, of erupting magma could exert important controls on eruption dynamics.

  10. Direct Observations Of Microbial Activity At Extreme Pressures

    NASA Astrophysics Data System (ADS)

    Sharma, A.; Scott, J. H.; Cody, G. D.; Fogel, M.; Hazen, R. M.; Hemley, R. J.; Huntress, W. T.

    2002-12-01

    Microbial communities adapt to a wide range of pressures, temperatures, salinities, pH, and oxidation states. Although, significant attention has been focused on the effects of high and low temperature on physiology, there is some evidence that elevated pressure may also manifest interesting effects on cellular physiology, such as enzyme inactivation, cell-membrane breach, and suppression of protein interactions with various substrates. However, exactly how these factors affect intact cells is not well understood. In this study, we have adapted diamond anvil cells to explore the effects of high pressure on microbial life. We used the rate of microbial formate oxidation as a probe of metabolic viability. The utilization of formate by microorganisms is a fundamental metabolic process in anaerobic environments. We monitored in-situ microbial formate oxidation via molecular spectroscopy for Shewanella oneidensis strain MR1 and Escherichia coli strain MG1655 at high pressures (68 to 1060 MPa). At pressures of 1200 to 1600 MPa, living bacteria resided in fluid inclusions in ice-VI crystals and continued to be viable upon subsequent release to ambient pressures (0.1 MPa). Furthermore, direct microscopic observations indicate that these cells maintain their ability for cellular division upon decompression from such high pressures. Evidence of microbial viability and activity at these extreme pressures expands by an order of magnitude the range of conditions representing the habitable zone in the solar system. These results imply that pressure may not be a significant impediment to life. The maximum pressure explored in this work is equivalent to a depth of ~ 50 km below Earth's crust, or ~ 160 km in a hypothetical ocean. The pressures encountered at the depths of thick ice caps and deep crustal subsurface may not be a limiting factor for the existence of life. This suggests that deep (water/ice) layers of Europa, Callisto, or Ganymede, subduction zones on Earth, and the polar ice caps of Mars might provide viable settings for life unhindered by the high pressures.

  11. Minimally Invasive Knee Arthroplasty with the Subvastus Approach Allows Rapid Rehabilitation: a Prospective, Biomechanical and Observational Study

    PubMed Central

    Lin, Tsung-Ching; Wang, Hsing-Kuo; Chen, Jia-Wine; Chiu, Cheng-Ming; Chou, Hsiu-Ling; Chang, Chih-Hung

    2013-01-01

    [Purpose] To study the recovery of patients treated with minimally invasive total knee arthroplasty (TKA) performed via the subvastus approach, and to develop an optimal rehabilitation program for these patients. [Methods] Twenty-two patients (17 females and 5 males; mean age 69.2?years), who received unilateral minimally invasive TKA for osteoarthritis, underwent isometric and isokinetic muscle testing and completed a quality of life questionnaire, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), before and after surgery. Muscle strength and ultrasound tests were repeated 1, 2, 6, and 12 months after surgery. [Results] Strength and range of motion were initially lower in the operated knees but demonstrated no significant difference from the healthy knees after 12 months. Sonographically, joint effusion was greater in the osteoarthritic knees than in the healthy knees at baseline, but no significant difference was observed after 12 months. The mean WOMAC pain, stiffness and function scores all decreased from baseline to 6 months, and then slightly increased at 12 months, but only the function score showed a significant difference compared to baseline. [Conclusions] One year after minimally invasive TKA using a subvastus approach, patients had a good overall prognosis, with prompt functional recovery. PMID:24259801

  12. Direct observation shows superposition and large scale flexibility within cytoplasmic dynein motors moving along microtubules

    PubMed Central

    Imai, Hiroshi; Shima, Tomohiro; Sutoh, Kazuo; Walker, Matthew L.; Knight, Peter J.; Kon, Takahide; Burgess, Stan A.

    2015-01-01

    Cytoplasmic dynein is a dimeric AAA+ motor protein that performs critical roles in eukaryotic cells by moving along microtubules using ATP. Here using cryo-electron microscopy we directly observe the structure of Dictyostelium discoideum dynein dimers on microtubules at near-physiological ATP concentrations. They display remarkable flexibility at a hinge close to the microtubule binding domain (the stalkhead) producing a wide range of head positions. About half the molecules have the two heads separated from one another, with both leading and trailing motors attached to the microtubule. The other half have the two heads and stalks closely superposed in a front-to-back arrangement of the AAA+ rings, suggesting specific contact between the heads. All stalks point towards the microtubule minus end. Mean stalk angles depend on the separation between their stalkheads, which allows estimation of inter-head tension. These findings provide a structural framework for understanding dynein's directionality and unusual stepping behaviour. PMID:26365535

  13. Direct observation shows superposition and large scale flexibility within cytoplasmic dynein motors moving along microtubules

    NASA Astrophysics Data System (ADS)

    Imai, Hiroshi; Shima, Tomohiro; Sutoh, Kazuo; Walker, Matthew L.; Knight, Peter J.; Kon, Takahide; Burgess, Stan A.

    2015-09-01

    Cytoplasmic dynein is a dimeric AAA+ motor protein that performs critical roles in eukaryotic cells by moving along microtubules using ATP. Here using cryo-electron microscopy we directly observe the structure of Dictyostelium discoideum dynein dimers on microtubules at near-physiological ATP concentrations. They display remarkable flexibility at a hinge close to the microtubule binding domain (the stalkhead) producing a wide range of head positions. About half the molecules have the two heads separated from one another, with both leading and trailing motors attached to the microtubule. The other half have the two heads and stalks closely superposed in a front-to-back arrangement of the AAA+ rings, suggesting specific contact between the heads. All stalks point towards the microtubule minus end. Mean stalk angles depend on the separation between their stalkheads, which allows estimation of inter-head tension. These findings provide a structural framework for understanding dynein's directionality and unusual stepping behaviour.

  14. Direct observation shows superposition and large scale flexibility within cytoplasmic dynein motors moving along microtubules.

    PubMed

    Imai, Hiroshi; Shima, Tomohiro; Sutoh, Kazuo; Walker, Matthew L; Knight, Peter J; Kon, Takahide; Burgess, Stan A

    2015-01-01

    Cytoplasmic dynein is a dimeric AAA(+) motor protein that performs critical roles in eukaryotic cells by moving along microtubules using ATP. Here using cryo-electron microscopy we directly observe the structure of Dictyostelium discoideum dynein dimers on microtubules at near-physiological ATP concentrations. They display remarkable flexibility at a hinge close to the microtubule binding domain (the stalkhead) producing a wide range of head positions. About half the molecules have the two heads separated from one another, with both leading and trailing motors attached to the microtubule. The other half have the two heads and stalks closely superposed in a front-to-back arrangement of the AAA(+) rings, suggesting specific contact between the heads. All stalks point towards the microtubule minus end. Mean stalk angles depend on the separation between their stalkheads, which allows estimation of inter-head tension. These findings provide a structural framework for understanding dynein's directionality and unusual stepping behaviour. PMID:26365535

  15. Direct observation of multistep energy transfer in LHCII with fifth-order 3D electronic spectroscopy

    PubMed Central

    Zhang, Zhengyang; Lambrev, Petar H.; Wells, Kym L.; Garab, Gy?z?; Tan, Howe-Siang

    2015-01-01

    During photosynthesis, sunlight is efficiently captured by light-harvesting complexes, and the excitation energy is then funneled towards the reaction centre. These photosynthetic excitation energy transfer (EET) pathways are complex and proceed in a multistep fashion. Ultrafast two-dimensional electronic spectroscopy (2DES) is an important tool to study EET processes in photosynthetic complexes. However, the multistep EET processes can only be indirectly inferred by correlating different cross peaks from a series of 2DES spectra. Here we directly observe multistep EET processes in LHCII using ultrafast fifth-order three-dimensional electronic spectroscopy (3DES). We measure cross peaks in 3DES spectra of LHCII that directly indicate energy transfer from excitons in the chlorophyll b (Chl b) manifold to the low-energy level chlorophyll a (Chl a) via mid-level Chl a energy states. This new spectroscopic technique allows scientists to move a step towards mapping the complete complex EET processes in photosynthetic systems. PMID:26228055

  16. Direct observation of multistep energy transfer in LHCII with fifth-order 3D electronic spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhang, Zhengyang; Lambrev, Petar H.; Wells, Kym L.; Garab, Gy?z?; Tan, Howe-Siang

    2015-07-01

    During photosynthesis, sunlight is efficiently captured by light-harvesting complexes, and the excitation energy is then funneled towards the reaction centre. These photosynthetic excitation energy transfer (EET) pathways are complex and proceed in a multistep fashion. Ultrafast two-dimensional electronic spectroscopy (2DES) is an important tool to study EET processes in photosynthetic complexes. However, the multistep EET processes can only be indirectly inferred by correlating different cross peaks from a series of 2DES spectra. Here we directly observe multistep EET processes in LHCII using ultrafast fifth-order three-dimensional electronic spectroscopy (3DES). We measure cross peaks in 3DES spectra of LHCII that directly indicate energy transfer from excitons in the chlorophyll b (Chl b) manifold to the low-energy level chlorophyll a (Chl a) via mid-level Chl a energy states. This new spectroscopic technique allows scientists to move a step towards mapping the complete complex EET processes in photosynthetic systems.

  17. Genetic-Algorithm Discovery of a Direct-Gap and Optically Allowed Superstructure from Indirect-Gap Si and Ge Semiconductors

    SciTech Connect

    d'Avezac, M.; Luo, J. W.; Chanier, T.; Zunger, A.

    2012-01-13

    Combining two indirect-gap materials - with different electronic and optical gaps - to create a direct gap material represents an ongoing theoretical challenge with potentially rewarding practical implications, such as optoelectronics integration on a single wafer. We provide an unexpected solution to this classic problem, by spatially melding two indirect-gap materials (Si and Ge) into one strongly dipole-allowed direct-gap material. We leverage a combination of genetic algorithms with a pseudopotential Hamiltonian to search through the astronomic number of variants of Si{sub n}/Ge{sub m}/.../Si{sub p}/Ge{sub q} superstructures grown on (001) Si{sub 1-x}Ge{sub x}. The search reveals a robust configurational motif - SiGe{sub 2}Si{sub 2}Ge{sub 2}SiGe{sub n} on (001) Si{sub x}Ge{sub 1-x} substrate (x {le} 0.4) presenting a direct and dipole-allowed gap resulting from an enhanced {Gamma}-X coupling at the band edges.

  18. A Study of Student Teaching Using Direct Observation.

    ERIC Educational Resources Information Center

    Coker, Joan G.; Coker, Homer

    Thirty-three student teachers were observed in elementary school classrooms to determine if they manifested 16 interactive behaviors identified as desirable by college of education faculty. Teaching assistants used the Georgia Assessment of Teaching Effectiveness (GATE), an instrument which requires the observers to objectively record, but not…

  19. Relation between Direct Observation of Relaxation and Self-Reported Mindfulness and Relaxation States

    ERIC Educational Resources Information Center

    Hites, Lacey S.; Lundervold, Duane A.

    2013-01-01

    Forty-four individuals, 18-47 (MN 21.8, SD 5.63) years of age, took part in a study examining the magnitude and direction of the relationship between self-report and direct observation measures of relaxation and mindfulness. The Behavioral Relaxation Scale (BRS), a valid direct observation measure of relaxation, was used to assess relaxed behavior…

  20. Direct Observation of Phase Separation in Microemulsion Networks

    E-print Network

    Tlusty, Tsvi

    of these phases consists of two-dimensional layers of amphiphiles separating oil and water domains that are both. Networks formed by interconnected oil- swollen cylinders were observed in the water-rich regions continuous.1 These dense symmetric sponges (at almost equal volume fractions of oil and water) have been

  1. Development of a Direct Observation Instrument to Measure Environmental Characteristics of Parks for Physical Activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study's purpose is to describe the development and evaluate the reliability (inter-observer agreement) and validity (rater agreement with a gold standard) of a direct observation instrument to assess park characteristics that may be related to physical activity. A direct observation instrument ...

  2. Direct observation of bubble-assisted electroluminescence in liquid xenon

    E-print Network

    Erdal, E; Chepel, V; Rappaport, M L; Vartsky, D; Breskin, A

    2015-01-01

    Bubble formation in liquid xenon underneath a Thick Gaseous Electron Multiplier (THGEM) electrode immersed in liquid xenon was observed with a CCD camera. With voltage across the THGEM, the appearance of bubbles was correlated with that of electroluminescence signals induced by ionization electrons from alpha-particle tracks. This confirms recent indirect evidence that the observed photons are due to electroluminescence within a xenon vapor layer trapped under the electrode. The bubbles seem to emerge spontaneously due to heat flow from 300K into the liquid, or in a controlled manner, by locally boiling the liquid with resistive wires. Controlled bubble formation resulted in energy resolution of {\\sigma}/E~7.5% for ~6,000 ionization electrons. The phenomenon could pave ways towards the conception of large-volume 'local dual-phase' noble-liquid TPCs.

  3. Direct observation of bubble-assisted electroluminescence in liquid xeno

    NASA Astrophysics Data System (ADS)

    Erdal, E.; Arazi, L.; Chepe, V.; Rappaport, M. L.; Vartsky, D.; Breskin, A.

    2015-11-01

    Bubble formation in liquid xenon underneath a Thick Gaseous Electron Multiplier (THGEM) electrode immersed in liquid xenon was observed with a CCD camera. With voltage across the THGEM, the appearance of bubbles was correlated with that of electroluminescence signals induced by ionization electrons from alpha-particle tracks. This confirms recent indirect evidence that the observed photons are due to electroluminescence within a xenon vapor layer trapped under the electrode. The bubbles seem to emerge spontaneously due to heat flow from 300 K into the liquid, or in a controlled manner by locally boiling the liquid with resistive wires. Controlled bubble formation resulted in energy resolution of ?/E ? 7.5% for ~ 6000 ionization electrons. The phenomenon could pave ways towards the conception of large-volume `local dual-phase' noble-liquid TPCs.

  4. Observation of uniaxial anisotropy along the [100] direction in crystalline Fe film

    PubMed Central

    Bac, Seul-Ki; Lee, Hakjoon; Lee, Sangyoep; Choi, Seonghoon; Yoo, Taehee; Lee, Sanghoon; Liu, X.; Furdyna, J. K.

    2015-01-01

    We report an observation of uniaxial magnetic anisotropy along the [100] crystallographic direction in crystalline Fe film grown on Ge buffers deposited on a (001) GaAs substrate. As expected, planar Hall resistance (PHR) measurements reveal the presence of four in-plane magnetic easy axes, indicating the dominance of the cubic anisotropy in the film. However, systematic mapping of the PHR hysteresis loops observed during magnetization reversal at different field orientations shows that the easy axes along the and are not equivalent. Such breaking of the cubic symmetry can only be ascribed to the presence of uniaxial anisotropy along the direction of the Fe film. Analysis of the PHR data measured as a function of orientation of the applied magnetic field allowed us to quantify the magnitude of this uniaxial anisotropy field as Oe. Although this value is only 1.5% of cubic anisotropy field, its presence significantly changes the process of magnetization reversal, revealing the important role of the uniaxial anisotropy in Fe films. Breaking of the cubic symmetry in the Fe film deposited on a Ge buffer is surprising, and we discuss possible reason for this unexpected behavior. PMID:26635278

  5. Direct observation of large temperature fluctuations during DNA thermal denaturation

    E-print Network

    K. S. Nagapriya; A. K. Raychaudhuri; Dipankar Chatterji

    2006-02-10

    In this paper we report direct measurement of large low frequency temperature fluctuations in double stranded (ds) DNA when it undergoes thermal denaturation transition. The fluctuation, which occurs only in the temperature range where the denaturation occurs, is several orders more than the expected equilibrium fluctuation. It is absent in single stranded (ss) DNA of the same sequence. The fluctuation at a given temperature also depends on the wait time and vanishes in a scale of few hours. It is suggested that the large fluctuation occurs due to coexisting denaturated and closed base pairs that are in dynamic equilibrium due to transition through a potential barrier in the scale of 25-30k_{B}T_{0}(T_{0}=300K).

  6. Direct observation of heterogeneous chemistry in the atmosphere

    PubMed

    Gard; Kleeman; Gross; Hughes; Allen; Morrical; Fergenson; Dienes; E Galli M; Johnson; Cass; Prather

    1998-02-20

    The heterogeneous replacement of chloride by nitrate in individual sea-salt particles was monitored continuously over time in the troposphere with the use of aerosol time-of-flight mass spectrometry. Modeling calculations show that the observed chloride displacement process is consistent with a heterogeneous chemical reaction between sea-salt particles and gas-phase nitric acid, leading to sodium nitrate production in the particle phase accompanied by liberation of gaseous HCl from the particles. Such single-particle measurements, combined with a single-particle model, make it possible to monitor and explain heterogeneous gas/particle chemistry as it occurs in the atmosphere. PMID:9469803

  7. Direct observation of reverse transcriptases by scanning tunneling microscopy.

    PubMed

    Lewerenz, H J; Jungblut, H; Campbell, S A; Giersig, M; Müller, D J

    1992-09-01

    First images on a nanometer scale of reverse transcriptases (RT) of the human immunodeficiency virus (HIV-1) and of the Moloney murine leukemia virus (MuLV) obtained by scanning tunneling microscopy (STM) are reported. The common feature of the observed molecules is a ring-type or horseshoe shape with hole diameters of approximately 30 A. The STM images are compared with high resolution transmission electron microscopy (TEM) and existing structure predictions. The similarities of the structural data obtained by STM and TEM and their agreement with the structure prediction for the RT of HIV-1 shows the principal possibility to image such biomolecules by STM. PMID:1280957

  8. Direct observation of the superconducting energy gap developing in the conductivity spectra of niobium

    E-print Network

    Roshchin, Igor V.

    of niobium A. V. Pronin,* M. Dressel, A. Pimenov, and A. Loidl Experimentalphysik V, Universita¨t Augsburg to investigate the amplitude and the phase of the transmission through niobium films that allows the direct

  9. The cosmic Mach number - Direct comparisons of observations and models

    NASA Technical Reports Server (NTRS)

    Strauss, Michael A.; Cen, Renyue; Ostriker, Jeremiah P.

    1993-01-01

    A robust method is used to derive the cosmic Mach number, M, from existing peculiar velocity data sets. For the IR Tully-Fisher distances of spirals in the Local Supercluster of Aaronson et al. (1979, 1982), M of 1.03 and a characteristic distance from the Local Group of 1464 km/s are found. For the elliptical galaxy sample of Faber et al. (1987, 1988), M of 0.57, with a characteristic distance of 2572 km/s is found. These results are compared with Monte Carlo simulations of the observational realizations drawn from numerical simulations of the universe based on various scenarios, including the standard cold dark matter (CDM) scenario. The effect of velocity bias on the derived Mach number is found to be small. Only 5 percent of the CDM simulations have M as large as or larger than that derived for the Aaronson et al. sample.

  10. Direct observation of the oceanic CO2 increase?revisited

    PubMed Central

    Brewer, Peter G.; Goyet, Catherine; Friederich, Gernot

    1997-01-01

    We show, from recent data obtained at specimen North Pacific stations, that the fossil fuel CO2 signal is strongly present in the upper 400 m, and that we may consider areal extrapolations from geochemical surveys to determine the magnitude of ocean fossil fuel CO2 uptake. The debate surrounding this topic is illustrated by contrasting reports which suggest, based upon atmospheric observations and models, that the oceanic CO2 sink is small at these latitudes; or that the oceanic CO2 sink, based upon oceanic data and models, is large. The difference between these two estimates is at least a factor of two. There are contradictions arising from estimates based on surface partial pressures of CO2 alone, where the signal sought is small compared with regional and seasonal variability; and estimates of the accumulated subsurface burden, which correlates well other oceanic tracers. Ocean surface waters today contain about 45 ?mol?kg?1 excess CO2 compared with those of the preindustrial era, and the signal is rising rapidly. What limits should we place on such calculations? The answer lies in the scientific questions to be asked. Recovery of the fossil fuel CO2 contamination signal from analysis of ocean water masses is robust enough to permit reasonable budget estimates. However, because we do not have sufficient data from the preindustrial ocean, the estimation of the required Redfield oxidation ratio in the upper several hundred meters is already blurred by the very fossil fuel CO2 signal we seek to resolve. PMID:11607738

  11. Direct observation of long-lived isomers in $^{212}$Bi

    E-print Network

    L. Chen; P. M. Walker; H. Geissel; Yu. A. Litvinov; K. Beckert; P. Beller; F. Bosch; D. Boutin; L. Caceres; J. J. Carroll; D. M. Cullen; I. J. Cullen; B. Franzke; J. Gerl; M. Górska; G. A. Jones; A. Kishada; R. Knöbel; C. Kozhuharov; J. Kurcewicz; S. A. Litvinov; Z. Liu; S. Mandal; F. Montes; G. Münzenberg; F. Nolden; T. Ohtsubo; Z. Patyk; W. R. Plaß; Zs. Podolyák; S. Rigby; N. Saito; T. Saito; C. Scheidenberger; E. C. Simpson; M. Shindo; M. Steck; B. Sun; S. J. Williams; H. Weick; M. Winkler; H. -J. Wollersheim; T. Yamaguchi

    2013-06-03

    Long-lived isomers in 212Bi have been studied following 238U projectile fragmentation at 670 MeV per nucleon. The fragmentation products were injected as highly charged ions into the GSI storage ring, giving access to masses and half-lives. While the excitation energy of the first isomer of 212Bi was confirmed, the second isomer was observed at 1478(30) keV, in contrast to the previously accepted value of >1910 keV. It was also found to have an extended Lorentz-corrected in-ring halflife >30 min, compared to 7.0(3) min for the neutral atom. Both the energy and half-life differences can be understood as being due a substantial, though previously unrecognised, internal decay branch for neutral atoms. Earlier shell-model calculations are now found to give good agreement with the isomer excitation energy. Furthermore, these and new calculations predict the existence of states at slightly higher energy that could facilitate isomer de-excitation studies.

  12. Direct Observation of Completely Processed Calcium Carbonate Dust Particles

    SciTech Connect

    Laskin, Alexander; Iedema, Martin J.; Ichkovich, Aviad; Graber, Ellen R.; Taraniuk, Ilya; Rudich, Yinon

    2005-05-27

    This study presents, for the first time, field evidence of complete, irreversible processing of solid calcium carbonate (calcite)-containing particles and quantitative formation of liquid calcium nitrate particles apparently as a result of heterogeneous reaction of calcium carbonate-containing mineral dust particles with gaseous nitric acid. Formation of nitrates from individual calcite and sea salt particles was followed as a function of time in aerosol samples collected at Shoresh, Israel. Morphology and compositional changes of individual particles were observed using conventional scanning electron microscopy with energy dispersive analysis of X-rays (SEM/EDX) and computer controlled SEM/EDX. Environmental scanning electron microscopy (ESEM) was utilized to determine and demonstrate the hygroscopic behavior of calcium nitrate particles found in some of the samples. Calcium nitrate particles are exceptionally hygroscopic and deliquesce even at very low relative humidity (RH) of 9 -11% which is lower than typical atmospheric environments. Transformation of non-hygroscopic dry mineral dust particles into hygroscopic wet aerosol may have substantial impacts on light scattering properties, the ability to modify clouds and heterogeneous chemistry.

  13. Constraining the Black Hole Mass Spectrum with LISA Observations II: Direct comparison of detailed models

    E-print Network

    Joseph E. Plowman; Ronald W. Hellings; Sachiko Tsuruta

    2010-09-03

    A number of scenarios have been proposed for the origin of the supermassive black holes (SMBHs) that are found in the centres of most galaxies. Many such scenarios predict a high-redshift population of massive black holes (MBHs), with masses in the range 100 to 100000 times that of the Sun. When the Laser Interferometer Space Antenna (LISA) is finally operational, it is likely that it will detect on the order of 100 of these MBH binaries as they merge. The differences between proposed population models produce appreciable effects in the portion of the population which is detectable by LISA, so it is likely that the LISA observations will allow us to place constraints on them. However, gravitational wave detectors such as LISA will not be able to detect all such mergers nor assign precise black hole parameters to the merger, due to weak gravitational wave signal strengths. This paper explores LISA's ability to distinguish between several MBH population models. In this way, we go beyond predicting a LISA observed population and consider the extent to which LISA observations could inform astrophysical modellers. The errors in LISA parameter estimation are applied with a direct method which generates random sample parameters for each source in a population realisation. We consider how the distinguishability varies depending on the choice of source parameters (1 or 2 parameters chosen from masses, redshift or spins) used to characterise the model distributions, with confidence levels determined by 1 and 2-dimensional tests based on the Kolmogorov-Smirnov test.

  14. Direct observation of mobility state transitions in RNA trajectories by sensitive single molecule feedback tracking

    PubMed Central

    Spille, Jan-Hendrik; Kaminski, Tim P.; Scherer, Katharina; Rinne, Jennifer S.; Heckel, Alexander; Kubitscheck, Ulrich

    2015-01-01

    Observation and tracking of fluorescently labeled molecules and particles in living cells reveals detailed information about intracellular processes on the molecular level. Whereas light microscopic particle observation is usually limited to two-dimensional projections of short trajectory segments, we report here image-based real-time three-dimensional single particle tracking in an active feedback loop with single molecule sensitivity. We tracked particles carrying only 1–3 fluorophores deep inside living tissue with high spatio-temporal resolution. Using this approach, we succeeded to acquire trajectories containing several hundred localizations. We present statistical methods to find significant deviations from random Brownian motion in such trajectories. The analysis allowed us to directly observe transitions in the mobility of ribosomal (r)RNA and Balbiani ring (BR) messenger (m)RNA particles in living Chironomus tentans salivary gland cell nuclei. We found that BR mRNA particles displayed phases of reduced mobility, while rRNA particles showed distinct binding events in and near nucleoli. PMID:25414330

  15. Capturing intraoperative process deviations using a direct observational approach: the glitch method

    PubMed Central

    Morgan, Lauren; Robertson, Eleanor; Hadi, Mohammed; Catchpole, Ken; Pickering, Sharon; New, Steve; Collins, Gary; McCulloch, Peter

    2013-01-01

    Objectives To develop a sensitive, reliable tool for enumerating and evaluating technical process imperfections during surgical operations. Design Prospective cohort study with direct observation. Setting Operating theatres on five sites in three National Health Service Trusts. Participants Staff taking part in elective and emergency surgical procedures in orthopaedics, trauma, vascular and plastic surgery; including anaesthetists, surgeons, nurses and operating department practitioners. Outcome measures Reliability and validity of the glitch count method; frequency, type, temporal pattern and rate of glitches in relation to site and surgical specialty. Results The glitch count has construct and face validity, and category agreement between observers is good (?=0.7). Redundancy between pairs of observers significantly improves the sensitivity over a single observation. In total, 429 operations were observed and 5742 glitches were recorded (mean 14 per operation, range 0–83). Specialty-specific glitch rates varied from 6.9 to 8.3/h of operating (ns). The distribution of glitch categories was strikingly similar across specialties, with distractions the commonest type in all cases. The difference in glitch rate between specialty teams operating at different sites was larger than that between specialties (range 6.3–10.5/h, p<0.001). Forty per cent of glitches occurred in the first quarter of an operation, and only 10% occurred in the final quarter. Conclusions The glitch method allows collection of a rich dataset suitable for analysing the changes following interventions to improve process safety, and appears reliable and sensitive. Glitches occur more frequently in the early stages of an operation. Hospital environment, culture and work systems may influence the operative process more strongly than the specialty. PMID:24282244

  16. 49 CFR 40.67 - When and how is a directly observed collection conducted?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false When and how is a directly observed collection conducted? 40.67 Section 40.67 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Urine Specimen Collections § 40.67 When and how is a directly observed collection...

  17. 10 CFR 26.115 - Collecting a urine specimen under direct observation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Collecting a urine specimen under direct observation. 26.115 Section 26.115 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for Testing § 26.115 Collecting a urine specimen under direct observation. (a) Procedures...

  18. 10 CFR 26.115 - Collecting a urine specimen under direct observation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Collecting a urine specimen under direct observation. 26.115 Section 26.115 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for Testing § 26.115 Collecting a urine specimen under direct observation. (a) Procedures...

  19. 10 CFR 26.115 - Collecting a urine specimen under direct observation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Collecting a urine specimen under direct observation. 26.115 Section 26.115 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for Testing § 26.115 Collecting a urine specimen under direct observation. (a) Procedures...

  20. 10 CFR 26.115 - Collecting a urine specimen under direct observation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Collecting a urine specimen under direct observation. 26.115 Section 26.115 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for Testing § 26.115 Collecting a urine specimen under direct observation. (a) Procedures...

  1. 10 CFR 26.115 - Collecting a urine specimen under direct observation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Collecting a urine specimen under direct observation. 26.115 Section 26.115 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for Testing § 26.115 Collecting a urine specimen under direct observation. (a) Procedures...

  2. Direct Observation of Virtual Electrode Formation Through a Novel Electrolyte-to-Electrode Transition

    NASA Astrophysics Data System (ADS)

    Siegel, David; El Gabaly, Farid; Bartelt, Norman; McCarty, Kevin

    2014-03-01

    Novel electrochemical solutions to problems in energy storage and transportation can drive renewable energy to become an economically viable alternative to fossil fuels. In many electrochemical systems, the behavior of a device can be fundamentally limited by the surface area of a triple phase boundary, the boundary region where a gas-phase species, electrode, and electrolyte coincide. When the electrode is an ionic insulator the triple phase boundary is typically a one-dimensional boundary with nanometer-scale thickness: ions cannot transport through the electrode, while electrons cannot be transported through the electrolyte. Here we present direct experimental measurements of a novel electrolyte-to-electrode transition with photoemission electron microscopy, and observe that the surface of an ionically conductive, electronically insulative solid oxide electrolyte undergoes a transition into a mixed electron-ion conductor in the vicinity of a metal electrode. Our direct experimental measurements allow us to characterize this system and address the mechanisms of ionic reactions and transport through comparisons with theoretical modeling to provide us with a physical picture of the processes involved. Our results provide insight into one of the mechanisms of ion transport in an electrochemical cell that may be generalizable to other systems.

  3. Direct Observation of Active Protein Folding Using Lock-in Force Spectroscopy

    PubMed Central

    Schlierf, Michael; Berkemeier, Felix; Rief, Matthias

    2007-01-01

    Direct observation of the folding of a single polypeptide chain can provide important information about the thermodynamic states populated along its folding pathway. In this study, we present a lock-in force-spectroscopy technique that improves resolution of atomic-force microscopy force spectroscopy to 400 fN. Using this technique we show that immunoglobulin domain 4 from Dictyostelium discoideum filamin (ddFLN4) refolds against forces of ?4 pN. Our data show folding of this domain proceeds directly from an extended state and no thermodynamically distinct collapsed state of the polypeptide before folding is populated. Folding of ddFLN4 under load proceeds via an intermediate state. Three-state folding allows ddFLN4 to fold against significantly larger forces than would be possible for a mere two-state folder. We present a general model for protein folding kinetics under load that can predict refolding forces based on chain-length and zero force refolding rate. PMID:17704164

  4. Heliospheric Observations of STEREO-Directed Coronal Mass Ejections in 2008 - 2010: Lessons for Future Observations of Earth-Directed CMEs

    NASA Astrophysics Data System (ADS)

    Lugaz, N.; Kintner, P.; Möstl, C.; Jian, L. K.; Davis, C. J.; Farrugia, C. J.

    2012-08-01

    We present a study of coronal mass ejections (CMEs) which impacted one of the STEREO spacecraft between January 2008 and early 2010. We focus our study on 20 CMEs which were observed remotely by the Heliospheric Imagers (HIs) onboard the other STEREO spacecraft up to large heliocentric distances. We compare the predictions of the Fixed-? and Harmonic Mean (HM) fitting methods, which only differ by the assumed geometry of the CME. It is possible to use these techniques to determine from remote-sensing observations the CME direction of propagation, arrival time and final speed which are compared to in-situ measurements. We find evidence that for large viewing angles, the HM fitting method predicts the CME direction better. However, this may be due to the fact that only wide CMEs can be successfully observed when the CME propagates more than 100? from the observing spacecraft. Overall eight CMEs, originating from behind the limb as seen by one of the STEREO spacecraft can be tracked and their arrival time at the other STEREO spacecraft can be successfully predicted. This includes CMEs, such as the events on 4 December 2009 and 9 April 2010, which were viewed 130? away from their direction of propagation. Therefore, we predict that some Earth-directed CMEs will be observed by the HIs until early 2013, when the separation between Earth and one of the STEREO spacecraft will be similar to the separation of the two STEREO spacecraft in 2009 - 2010.

  5. Rationale and design of a randomized controlled trial of varenicline directly observed therapy delivered in methadone clinics

    PubMed Central

    2014-01-01

    Background Tobacco cessation medication adherence is one of the few factors shown to improve smoking cessation rates among methadone-maintained smokers, but interventions to improve adherence to smoking cessation medications have not yet been tested among methadone treatment patients. Methadone clinic-based, directly observed therapy (DOT) programs for HIV and tuberculosis improve adherence and clinical outcomes, but have not been evaluated for smoking cessation. We describe a randomized controlled trial to evaluate whether a methadone clinic-based, directly observed varenicline therapy program increases adherence and tobacco abstinence among opioid-dependent drug users receiving methadone treatment. Methods/Design We plan to enroll 100 methadone-maintained smokers and randomize them to directly observed varenicline dispensed with daily methadone doses or treatment as usual (self-administered varenicline) for 12 weeks. Our outcome measures are: 1) pill count adherence and 2) carbon monoxide-verified tobacco abstinence. We will assess differences in adherence and abstinence between the two treatment arms using repeated measures models. Discussion This trial will allow for rigorous evaluation of the efficacy of methadone clinic-based, directly observed varenicline for improving adherence and smoking cessation outcomes. This detailed description of trial methodology can serve as a template for the development of future DOT programs and can guide protocols for studies among opioid-dependent smokers receiving methadone treatment. Trial Registration clinicaltrials.gov NCT01378858 PMID:24928218

  6. Mid-depth recirculation observed in the interior Labrador and Irminger seas by direct velocity measurements

    PubMed

    Lavender; Davis; Owens

    2000-09-01

    The Labrador Sea is one of the sites where convection exports surface water to the deep ocean in winter as part of the thermohaline circulation. Labrador Sea water is characteristically cold and fresh, and it can be traced at intermediate depths (500-2,000 m) across the North Atlantic Ocean, to the south and to the east of the Labrador Sea. Widespread observations of the ocean currents that lead to this distribution of Labrador Sea water have, however, been difficult and therefore scarce. We have used more than 200 subsurface floats to measure directly basin-wide horizontal velocities at various depths in the Labrador and Irminger seas. We observe unanticipated recirculations of the mid-depth (approximately 700 m) cyclonic boundary currents in both basins, leading to an anticyclonic flow in the interior of the Labrador basin. About 40% of the floats from the region of deep convection left the basin within one year and were rapidly transported in the anticyclonic flow to the Irminger basin, and also eastwards into the subpolar gyre. Surprisingly, the float tracks did not clearly depict the deep western boundary current, which is the expected main pathway of Labrador Sea water in the thermohaline circulation. Rather, the flow along the boundary near Flemish Cap is dominated by eddies that transport water offshore. Our detailed observations of the velocity structure with a high data coverage suggest that we may have to revise our picture of the formation and spreading of Labrador Sea water, and future studies with similar instrumentation will allow new insights on the intermediate depth ocean circulation. PMID:10993072

  7. Wide-field direct CCD observations supporting the Astro-1 Space Shuttle mission's Ultraviolet Imaging Telescope

    NASA Technical Reports Server (NTRS)

    Hintzen, Paul; Angione, Ron; Talbert, Freddie; Cheng, K.-P.; Smith, Eric; Stecher, Theodore P.

    1993-01-01

    Wide field direct CCD observations are being obtained to support and complement the vacuum-ultraviolet (VUV) images provided by Astro's Ultraviolet Imaging Telescope (UIT) during a Space Shuttle flight in December 1990. Because of the wide variety of projects addressed by UIT, the fields observed include (1) galactic supernova remnants such as the Cygnus Loop and globular clusters such as Omega Cen and M79; (2) the Magellanic Clouds, M33, M81, and other galaxies in the Local Group; and (3) rich clusters of galaxies, principally the Perseus cluster and Abell 1367. Ground-based observations have been obtained for virtually all of the Astro-1 UIT fields. The optical images allow identification of individual UV sources in each field and provide the long baseline in wavelength necessary for accurate analysis of UV-bright sources. To facilitate use of our optical images for analysis of UIT data and other projects, we plan to archive them, with the UIT images, at the National Space Science Data Center (NSSDC), where they will be universally accessible via anonymous FTP. The UIT, one of three telescopes comprising the Astro spacecraft, is a 38-cm f/9 Ritchey-Chretien telescope on which high quantum efficiency, solar-blind image tubes are used to record VUV images on photographic film. Five filters with passbands centered between 1250A and 2500A provide both VUV colors and a measurement of extinction via the 2200A dust feature. The resulting calibrated VUV pictures are 40 arcminutes in diameter at 2.5 arcseconds resolution. The capabilities of UIT, therefore, complement HST's WFPC: the latter has 40 times greater collecting area, while UIT's usable field has 170 times WFPC's field area.

  8. Direct Observation of Dark Excitons in Individual Carbon Nanotubes: Inhomogeneity in the Exchange Splitting

    E-print Network

    Natelson, Douglas

    Direct Observation of Dark Excitons in Individual Carbon Nanotubes: Inhomogeneity in the Exchange-triplet splitting, giving rise to exciton fine structure consisting of four singlet and 12 trip- let, partially

  9. Direct observation of Rydberg-Rydberg transitions via CPmmW spectroscopy

    E-print Network

    Zhou, Yan, Ph. D. Massachusetts Institute of Technology

    2014-01-01

    Rydberg-Rydberg transitions of BaF molecules have been directly observed in our lab. The key to the experimental success is our ability to combine two powerful and new technologies, Chirped-Pulse millimeter-Wave spectroscopy ...

  10. Direct retrieval of ocean surface evaporation and latent heat flux from the spacebased observations

    NASA Technical Reports Server (NTRS)

    Liu, W. T.; Tang, W.

    2000-01-01

    The Tropical Rain Measuring Mission (TRMM) provides the opportunity to improve the spacebased estimation of evaporation. An algorithm for retrieving evaporation directly from the radiances observed by the TRMM Microwave Imager and its validation results are described.

  11. Alignment of micro-crystals of Mn12-acetate and direct observation of single molecules thereof 

    E-print Network

    Seo, Dongmin

    2009-05-15

    OF MICRO-CRYSTALS OF MN 12 -ACETATE AND DIRECT OBSERVATION OF SINGLE MOLECULES THEREOF A Dissertation by DONGMIN SEO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of DOCTOR OF PHILOSOPHY December 2007 Major Subject: Physics ALIGNMENT OF MICRO-CRYSTALS OF MN 12 -ACETATE AND DIRECT OBSERVATION OF SINGLE MOLECULES THEREOF A Dissertation by DONGMIN SEO Submitted to the Office...

  12. Instructional Interactions of Kindergarten Mathematics Classrooms: Validating a Direct Observation Instrument

    ERIC Educational Resources Information Center

    Doabler, Christian; Smolkowski, Keith; Fien, Hank; Kosty, Derek B.; Cary, Mari Strand

    2010-01-01

    In this paper, the authors report research focused directly on the validation of the Coding of Academic Teacher-Student interactions (CATS) direct observation instrument. They use classroom information gathered by the CATS instrument to better understand the potential mediating variables hypothesized to influence student achievement. Their study's…

  13. Direct observation of roaming radicals in the thermal decomposition of acetaldehyde.

    SciTech Connect

    Sivaramakrishnan, R.; Michael, J. V.; Klippenstein, S. J.; Chemical Sciences and Engineering Division

    2010-01-21

    The thermal dissociation of acetaldehyde has been studied with the reflected shock tube technique using H(D)-atom atomic resonance absorption spectrometry detection. The use of an unreversed light source yields extraordinarily sensitive H atom detection. As a result, we are able to measure both the total decomposition rate and the branching to radical versus molecular channels. This branching provides a direct measure of the contribution from the roaming radical mechanism since the contributions from the usual tight transition states are predicted by theory to be negligible. The experimental observations also provide a measure of the rate coefficient for H + CH{sub 3}CHO. Another set of experiments employing C{sub 2}H{sub 5}I as an H-atom source provides additional data for this rate coefficient that extends to lower temperature. An evaluation of the available experimental results for H + CH{sub 3}CHO can be expressed by a three-parameter Arrhenius expression as k = 7.66 x 10{sup -20}T{sup 2.75} exp((-486 K)/T) cm{sup 3} molecule{sup -1} s{sup -1} (298-1415 K). Analogous experiments employing C{sub 2}D{sub 5}I as a D-atom source allow for the study of the isotopically substituted reaction. The present experiments are the only direct measure for this reaction rate constant, and the results can be expressed by an Arrhenius expression as k = 5.20 x 10{sup -10} exp((-4430 K)/T) cm{sup 3} molecule{sup -1} s{sup -1} (1151-1354 K). The H/D + CH{sub 3}CHO reactions are also studied with ab initio transition-state theory, and the results are in remarkably good agreement with the current experimental data.

  14. Direct observation of the indirect to direct band gap transition in epitaxial monolayer MoSe2 film

    NASA Astrophysics Data System (ADS)

    Zhang, Yi; Chang, Tay-Rong; Zhou, Bo; Cui, Yong-Tao; Yan, Hao; Liu, Zhongkai; Schmitt, Felix; Lee, James; Moore, Rob; Chen, Yulin; Lin, Hsin; Jeng, Hong-Tay; Mo, Sung-Kwan; Hussain, Zahid; Bansil, Arun; Shen, Zhi-Xun

    2014-03-01

    As a class of graphene-like two-dimensional materials, the layered metal dichalcogenides MX2 (M = Mo, W; X = S, Se, Te) have gained significant interest due to the indirect to direct band gap transition in monolayer. Because of this direct band gap, monolayer MX2 is favorable for optoelectronic applications. Here we report the direct observation such band gap transition by using angle-resolved photoemission spectroscopy on high-quality thin films of MoSe2, with variable thickness from monolayer to 8 monolayer, grown by molecular beam epitaxy. The experimental band structure indicates a stronger tendency of monolayer MoSe2 towards direct band gap, and with larger gap size, than theoretical prediction. Moreover, we observed a significant band splitting of ~ 180 meV at valence band maximum of a monolayer MoSe2, which was theoretically predicted to be 100% spin-polarized. This spin signature gives the layered MoSe2 great application potential in spintronic devices, as well as a new playground to investigate spin-obit physics beyond the topological insulators.

  15. Direct observation of electron propagation and dielectric screening on the atomic length scale.

    PubMed

    Neppl, S; Ernstorfer, R; Cavalieri, A L; Lemell, C; Wachter, G; Magerl, E; Bothschafter, E M; Jobst, M; Hofstetter, M; Kleineberg, U; Barth, J V; Menzel, D; Burgdörfer, J; Feulner, P; Krausz, F; Kienberger, R

    2015-01-15

    The propagation and transport of electrons in crystals is a fundamental process pertaining to the functioning of most electronic devices. Microscopic theories describe this phenomenon as being based on the motion of Bloch wave packets. These wave packets are superpositions of individual Bloch states with the group velocity determined by the dispersion of the electronic band structure near the central wavevector in momentum space. This concept has been verified experimentally in artificial superlattices by the observation of Bloch oscillations--periodic oscillations of electrons in real and momentum space. Here we present a direct observation of electron wave packet motion in a real-space and real-time experiment, on length and time scales shorter than the Bloch oscillation amplitude and period. We show that attosecond metrology (1 as = 10(-18) seconds) now enables quantitative insight into weakly disturbed electron wave packet propagation on the atomic length scale without being hampered by scattering effects, which inevitably occur over macroscopic propagation length scales. We use sub-femtosecond (less than 10(-15) seconds) extreme-ultraviolet light pulses to launch photoelectron wave packets inside a tungsten crystal that is covered by magnesium films of varied, well-defined thicknesses of a few ångströms. Probing the moment of arrival of the wave packets at the surface with attosecond precision reveals free-electron-like, ballistic propagation behaviour inside the magnesium adlayer--constituting the semi-classical limit of Bloch wave packet motion. Real-time access to electron transport through atomic layers and interfaces promises unprecedented insight into phenomena that may enable the scaling of electronic and photonic circuits to atomic dimensions. In addition, this experiment allows us to determine the penetration depth of electrical fields at optical frequencies at solid interfaces on the atomic scale. PMID:25592539

  16. Nature of Fluctuations on Directional Discontinuities Inside a Solar Ejection: Wind and IMP 8 Observations

    NASA Technical Reports Server (NTRS)

    Vasquez, Bernard J.; Farrugia, Charles J.; Markovskii, Sergei A.; Hollweg, Joseph V.; Richardson, Ian G.; Ogilvie, Keith W.; Lepping, Ronald P.; Lin, Robert P.; Larson, Davin; White, Nicholas E. (Technical Monitor)

    2001-01-01

    A solar ejection passed the Wind spacecraft between December 23 and 26, 1996. On closer examination, we find a sequence of ejecta material, as identified by abnormally low proton temperatures, separated by plasmas with typical solar wind temperatures at 1 AU. Large and abrupt changes in field and plasma properties occurred near the separation boundaries of these regions. At the one boundary we examine here, a series of directional discontinuities was observed. We argue that Alfvenic fluctuations in the immediate vicinity of these discontinuities distort minimum variance normals, introducing uncertainty into the identification of the discontinuities as either rotational or tangential. Carrying out a series of tests on plasma and field data including minimum variance, velocity and magnetic field correlations, and jump conditions, we conclude that the discontinuities are tangential. Furthermore, we find waves superposed on these tangential discontinuities (TDs). The presence of discontinuities allows the existence of both surface waves and ducted body waves. Both probably form in the solar atmosphere where many transverse nonuniformities exist and where theoretically they have been expected. We add to prior speculation that waves on discontinuities may in fact be a common occurrence. In the solar wind, these waves can attain large amplitudes and low frequencies. We argue that such waves can generate dynamical changes at TDs through advection or forced reconnection. The dynamics might so extensively alter the internal structure that the discontinuity would no longer be identified as tangential. Such processes could help explain why the occurrence frequency of TDs observed throughout the solar wind falls off with increasing heliocentric distance. The presence of waves may also alter the nature of the interactions of TDs with the Earth's bow shock in so-called hot flow anomalies.

  17. Direct Observation of the Transition from Calcite to Aragonite Growth as Induced by Abalone Shell Proteins

    E-print Network

    Hansma, Paul

    Direct Observation of the Transition from Calcite to Aragonite Growth as Induced by Abalone Shell are known to cause the nucleation and growth of aragonite on calcite seed crystals in supersaturated with calcite crystals did not observe this transition because no information about the crystal polymorph

  18. Direct observation of cavitation fields at 23 and 515 kHz.

    PubMed

    Price, Gareth J; Harris, Naomi K; Stewart, Alison J

    2010-01-01

    Direct observation of cavitation fields using photography, sonoluminescence and luminol "mapping" is reported for a 23 kHz horn sonicator and a 515 kHz plate transducer system. The effect of sound intensity and added surfactant on the cavitation fields is described. The observations support previously reported results suggesting significant differences in the cavitation fields between the two sonication systems. PMID:19464940

  19. Increased corticospinal excitability during direct observation of self-movement and indirect observation with a mirror box.

    PubMed

    Funase, Kozo; Tabira, Takayuki; Higashi, Toshio; Liang, Nan; Kasai, Tatsuya

    2007-05-29

    To explore the effect of mirror box therapy based on the mirror neuron (MN) system of the primary motor cortex (M1), we examined if direct (without a mirror) and indirect (with a mirror) observation of self-movement in healthy subjects induced changes in motor evoked potential (MEP) evoked by transcranial magnetic stimulation (TMS). MEPs were elicited from the first dorsal interosseous (FDI) and the flexor carpi radialis (FCR) muscles. Somatosensory evoked potentials (SEPs) during self-movement observation were also recorded. Both observations of self-movement with and without a mirror increased MEP amplitude. In addition, increase in MEP amplitude was specific to the prime mover muscle involved in the observed movement. The SEPs increased similar to the MEPs during both observations of self-movement with and without a mirror. We conclude that although the MN system can be activated by observing self-movement in a manner similar to that achieved by observing movement of another person, there were no detectable effect on corticospinal excitability that were specific to movements observed with a mirror. PMID:17481817

  20. DigiSwitch: A device to allow older adults to monitor and direct the collection and transmission of health information collected at home

    E-print Network

    Camp, L. Jean

    -Zimmerman, William R. Hazlewood, L. Jean Camp, Katherine H. Connelly, Lesa L. Huber, and Kalpana Shankar School, L. J., Connelly, K. H., Huber, L. L, & Shankar, K, "DigiSwitch: A device to allow older adults

  1. Direct observation of the transition from indirect to direct bandgap in atomically thin epitaxial MoSe2.

    PubMed

    Zhang, Yi; Chang, Tay-Rong; Zhou, Bo; Cui, Yong-Tao; Yan, Hao; Liu, Zhongkai; Schmitt, Felix; Lee, James; Moore, Rob; Chen, Yulin; Lin, Hsin; Jeng, Horng-Tay; Mo, Sung-Kwan; Hussain, Zahid; Bansil, Arun; Shen, Zhi-Xun

    2014-02-01

    Quantum systems in confined geometries are host to novel physical phenomena. Examples include quantum Hall systems in semiconductors and Dirac electrons in graphene. Interest in such systems has also been intensified by the recent discovery of a large enhancement in photoluminescence quantum efficiency and a potential route to valleytronics in atomically thin layers of transition metal dichalcogenides, MX2 (M = Mo, W; X = S, Se, Te), which are closely related to the indirect-to-direct bandgap transition in monolayers. Here, we report the first direct observation of the transition from indirect to direct bandgap in monolayer samples by using angle-resolved photoemission spectroscopy on high-quality thin films of MoSe2 with variable thickness, grown by molecular beam epitaxy. The band structure measured experimentally indicates a stronger tendency of monolayer MoSe2 towards a direct bandgap, as well as a larger gap size, than theoretically predicted. Moreover, our finding of a significant spin-splitting of ? 180 meV at the valence band maximum of a monolayer MoSe2 film could expand its possible application to spintronic devices. PMID:24362235

  2. Direct observation of the transition from indirect to direct bandgap in atomically thin epitaxial MoSe2

    NASA Astrophysics Data System (ADS)

    Zhang, Yi; Chang, Tay-Rong; Zhou, Bo; Cui, Yong-Tao; Yan, Hao; Liu, Zhongkai; Schmitt, Felix; Lee, James; Moore, Rob; Chen, Yulin; Lin, Hsin; Jeng, Horng-Tay; Mo, Sung-Kwan; Hussain, Zahid; Bansil, Arun; Shen, Zhi-Xun

    2014-02-01

    Quantum systems in confined geometries are host to novel physical phenomena. Examples include quantum Hall systems in semiconductors and Dirac electrons in graphene. Interest in such systems has also been intensified by the recent discovery of a large enhancement in photoluminescence quantum efficiency and a potential route to valleytronics in atomically thin layers of transition metal dichalcogenides, MX2 (M = Mo, W; X = S, Se, Te), which are closely related to the indirect-to-direct bandgap transition in monolayers. Here, we report the first direct observation of the transition from indirect to direct bandgap in monolayer samples by using angle-resolved photoemission spectroscopy on high-quality thin films of MoSe2 with variable thickness, grown by molecular beam epitaxy. The band structure measured experimentally indicates a stronger tendency of monolayer MoSe2 towards a direct bandgap, as well as a larger gap size, than theoretically predicted. Moreover, our finding of a significant spin-splitting of ~180 meV at the valence band maximum of a monolayer MoSe2 film could expand its possible application to spintronic devices.

  3. 40 CFR 26.405 - Observational research involving greater than minimal risk but presenting the prospect of direct...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual subjects...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual...

  4. 40 CFR 26.405 - Observational research involving greater than minimal risk but presenting the prospect of direct...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual subjects...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual...

  5. 40 CFR 26.405 - Observational research involving greater than minimal risk but presenting the prospect of direct...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual subjects...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual...

  6. 40 CFR 26.405 - Observational research involving greater than minimal risk but presenting the prospect of direct...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual subjects...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual...

  7. 40 CFR 26.405 - Observational research involving greater than minimal risk but presenting the prospect of direct...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual subjects...Observational research involving greater than minimal risk but presenting the prospect of direct benefit to the individual...

  8. Objectively Optimized Observation Direction System Providing Situational Awareness for a Sensor Web

    NASA Astrophysics Data System (ADS)

    Aulov, O.; Lary, D. J.

    2010-12-01

    There is great utility in having a flexible and automated objective observation direction system for the decadal survey missions and beyond. Such a system allows us to optimize the observations made by suite of sensors to address specific goals from long term monitoring to rapid response. We have developed such a prototype using a network of communicating software elements to control a heterogeneous network of sensor systems, which can have multiple modes and flexible viewing geometries. Our system makes sensor systems intelligent and situationally aware. Together they form a sensor web of multiple sensors working together and capable of automated target selection, i.e. the sensors “know” where they are, what they are able to observe, what targets and with what priorities they should observe. This system is implemented in three components. The first component is a Sensor Web simulator. The Sensor Web simulator describes the capabilities and locations of each sensor as a function of time, whether they are orbital, sub-orbital, or ground based. The simulator has been implemented using AGIs Satellite Tool Kit (STK). STK makes it easy to analyze and visualize optimal solutions for complex space scenarios, and perform complex analysis of land, sea, air, space assets, and shares results in one integrated solution. The second component is target scheduler that was implemented with STK Scheduler. STK Scheduler is powered by a scheduling engine that finds better solutions in a shorter amount of time than traditional heuristic algorithms. The global search algorithm within this engine is based on neural network technology that is capable of finding solutions to larger and more complex problems and maximizing the value of limited resources. The third component is a modeling and data assimilation system. It provides situational awareness by supplying the time evolution of uncertainty and information content metrics that are used to tell us what we need to observe and the priority we should give to the observations. A prototype of this component was implemented with AutoChem. AutoChem is NASA release software constituting an automatic code generation, symbolic differentiator, analysis, documentation, and web site creation tool for atmospheric chemical modeling and data assimilation. Its model is explicit and uses an adaptive time-step, error monitoring time integration scheme for stiff systems of equations. AutoChem was the first model to ever have the facility to perform 4D-Var data assimilation and Kalman filter. The project developed a control system with three main accomplishments. First, fully multivariate observational and theoretical information with associated uncertainties was combined using a full Kalman filter data assimilation system. Second, an optimal distribution of the computations and of data queries was achieved by utilizing high performance computers/load balancing and a set of automatically mirrored databases. Third, inter-instrument bias correction was performed using machine learning. The PI for this project was Dr. David Lary of the UMBC Joint Center for Earth Systems Technology at NASA/Goddard Space Flight Center.

  9. Boundary Layer Ozone Dynamics: Direct Observations over Arctic and Ocean Locations

    NASA Astrophysics Data System (ADS)

    Boylan, Patrick Joseph

    Influences of anthropogenic emissions from the northern hemisphere mid-latitudes can be seen in remote arctic and oceanic regions previously thought to be removed from the effects of pollution. Direct observations of surface layer ozone have been underrepresented above the hydrosphere and cryosphere. With oceans covering two thirds of the Earth's surface, the air-sea exchange plays an important role in the surface energy budget and in the transfer of ozone to the ocean surface. Recent developments of a fast response ozone instrument have allowed for ozone flux measurements over the open ocean. I investigated the quenching effect due to water vapor on the ozone instrument and quantified the corrections required for accurate measurements. A method for removing water vapor while leaving ozone unchanged was described. Mean water vapor concentrations were reduced by 77% and fast fluctuations of the water vapor signal were reduced by 97%. The transport of ozone over the open ocean was examined at island monitoring stations and from ship-board measurements. It has been speculated that ozone ocean uptake is determined by chemical enhancements. Currently, limited concurrent measurements of ozone flux and ocean surface chemistry have occurred. This work examined the use of satellite derived ocean surface chemistry measurements. In-situ and satellite derived measurements of chlorophyll agreed within 1 ?g l-1 when the wind speed was greater than 6 m s-1. The fast response ozone instrument was deployed during a two month long field campaign to study ozone depletion events in Barrow, Alaska. During the campaign, seven ozone depletion events (ODE) where the ozone would drop below 1.0 ppbv were observed. The longest ODE lasted over 72 hours with residual ozone varying between 0.1 to 0.8 ppbv. Ozone surface deposition rates were relatively low, ? 0.02-0.05 cm s-1 during most times. There was no clear evidence of ozone in interstitial air being influenced by photochemical processes. Concurrent atmospheric turbulence measurements from seven sonic anemometers showed general agreement except when winds were disturbed by the location of a nearby building. A composite boundary layer height was defined during the campaign, based on atmospheric turbulence measurements and validated against over 100 radiosonde observations. Sustained periods of boundary layer heights below 50 m were seen for several days. There was not a clear correlation between ozone depletion events and boundary layer height.

  10. Observations of the relationship between directionality and decay rate of radon in a confined experiment

    NASA Astrophysics Data System (ADS)

    Steinitz, G.; Kotlarsky, P.; Piatibratova, O.

    2015-05-01

    Radon (222Rn) is a radioactive inert gas with an accepted half life of 3.8235 days. Its unique, systematic and complex variation in the geological environment and in simulation experiments combined with lack of understanding of the underlying drivers lead us to conduct tests of its apparent half life. A primary test took into account experimental observations indicating anisotropy of the gamma radiation from radon in air, which is related to global orientation. Using a goniometric configuration radon diffuses into two identical cylinders oriented along Earth axis of rotation and in a vertical and perpendicular direction to the latter. Detectors placed on cylinder ends measure gamma radiation sub parallel to these directions. At steady state and confined conditions different patterns of daily signals are observed in the two directions. Isolating the cylinders from the source leads to an exponential decrease on which similar daily signals are superimposed, having amplitudes proportional to the level of the remaining radon. The indicated apparent half-lives are in significant difference from the accepted value: 0.861 ± 0.003 days in the pole direction and 2.308 ± 0.008 days in the vertical direction. The outcome is in conformity with observations on radon signals in confined conditions and their different manifestation at different directions.

  11. Unimolecular thermal decomposition of phenol and d5-phenol: Direct observation of cyclopentadiene formation via cyclohexadienone

    NASA Astrophysics Data System (ADS)

    Scheer, Adam M.; Mukarakate, Calvin; Robichaud, David J.; Nimlos, Mark R.; Carstensen, Hans-Heinrich; Barney Ellison, G.

    2012-01-01

    The pyrolyses of phenol and d5-phenol (C6H5OH and C6D5OH) have been studied using a high temperature, microtubular (?tubular) SiC reactor. Product detection is via both photon ionization (10.487 eV) time-of-flight mass spectrometry and matrix isolation infrared spectroscopy. Gas exiting the heated reactor (375 K-1575 K) is subject to a free expansion after a residence time in the ?tubular reactor of approximately 50-100 ?s. The expansion from the reactor into vacuum rapidly cools the gas mixture and allows the detection of radicals and other highly reactive intermediates. We find that the initial decomposition steps at the onset of phenol pyrolysis are enol/keto tautomerization to form cyclohexadienone followed by decarbonylation to produce cyclopentadiene; C6H5OH ? c-C6H6 = O ? c-C5H6 + CO. The cyclopentadiene loses a H atom to generate the cyclopentadienyl radical which further decomposes to acetylene and propargyl radical; c-C5H6 ? c-C5H5 + H ? HC?CH + HCCCH2. At higher temperatures, hydrogen loss from the PhO-H group to form phenoxy radical followed by CO ejection to generate the cyclopentadienyl radical likely contributes to the product distribution; C6H5O-H ? C6H5O + H ? c-C5H5 + CO. The direct decarbonylation reaction remains an important channel in the thermal decomposition mechanisms of the dihydroxybenzenes. Both catechol (o-HO-C6H4-OH) and hydroquinone (p-HO-C6H4-OH) are shown to undergo decarbonylation at the onset of pyrolysis to form hydroxycyclopentadiene. In the case of catechol, we observe that water loss is also an important decomposition channel at the onset of pyrolysis.

  12. Directional surface plasmon coupled chemiluminescence from nickel thin films: Fixed angle observation

    NASA Astrophysics Data System (ADS)

    Weisenberg, Micah; Aslan, Kadir; Hortle, Elinor; Geddes, Chris D.

    2009-04-01

    Directional surface plasmon coupled chemiluminescence (SPCC) from nickel thin films is demonstrated. Free-space and angular-dependent SPCC emission from blue, green and turquoise chemiluminescent solutions placed onto nickel thin films attached to a hemispherical prism were measured. SPCC emission was found to be highly directional and preferentially p-polarized, in contrast to the unpolarized and isotropic chemiluminescence emission. The largest SPCC emission for all chemiluminescence solutions was observed at a fixed observation angle of 60°, which was also predicted by theoretical Fresnel calculations. It was found that nickel thin films did not have a catalytic effect on chemiluminescence emission.

  13. A Review of Direct Observation Research within the Past Decade in the Field of Emotional and Behavioral Disorders

    ERIC Educational Resources Information Center

    Adamson, Reesha M.; Wachsmuth, Sean T.

    2014-01-01

    This study reviewed prominent journals within the field of emotional and behavioral disorders to identify direct observation approaches, reported reliability statistics, and key features of direct observation. Selected journals were systematically reviewed for the past 10 years identifying and quantifying specific direct observation systems and…

  14. Direct Observation of Excitonic Lasing from Single ZnO Nanobelts at Room Temperature

    NASA Astrophysics Data System (ADS)

    Bando, Kazuki; Sawabe, Taiki; Asaka, Koji; Masumoto, Yasuaki

    2005-06-01

    Excitonic lasing from single ZnO nanobelts was observed at room temperature, which was due to the exciton-exciton scattering processes appearing under intense light excitation. Morphologies of the nanobelts are rectangular shapes, so that crystalline facets of the nanobelts acted as the lasing cavity mirrors. We demonstrated that mode spacings correspond to cavity lengths of the respective nanobelts, and directly observed the lasing from single ZnO nanobelts by mapping of the luminescence intensity.

  15. Direct observation of liquid crystals using cryo-TEM: specimen preparation and low-dose imaging.

    PubMed

    Gao, Min; Kim, Young-Ki; Zhang, Cuiyu; Borshch, Volodymyr; Zhou, Shuang; Park, Heung-Shik; Jákli, Antal; Lavrentovich, Oleg D; Tamba, Maria-Gabriela; Kohlmeier, Alexandra; Mehl, Georg H; Weissflog, Wolfgang; Studer, Daniel; Zuber, Benoît; Gnägi, Helmut; Lin, Fang

    2014-10-01

    Liquid crystals (LCs) represent a challenging group of materials for direct transmission electron microscopy (TEM) studies due to the complications in specimen preparation and the severe radiation damage. In this paper, we summarize a series of specimen preparation methods, including thin film and cryo-sectioning approaches, as a comprehensive toolset enabling high-resolution direct cryo-TEM observation of a broad range of LCs. We also present comparative analysis using cryo-TEM and replica freeze-fracture TEM on both thermotropic and lyotropic LCs. In addition to the revisits of previous practices, some new concepts are introduced, e.g., suspended thermotropic LC thin films, combined high-pressure freezing and cryo-sectioning of lyotropic LCs, and the complementary applications of direct TEM and indirect replica TEM techniques. The significance of subnanometer resolution cryo-TEM observation is demonstrated in a few important issues in LC studies, including providing direct evidences for the existence of nanoscale smectic domains in nematic bent-core thermotropic LCs, comprehensive understanding of the twist-bend nematic phase, and probing the packing of columnar aggregates in lyotropic chromonic LCs. Direct TEM observation opens ways to a variety of TEM techniques, suggesting that TEM (replica, cryo, and in situ techniques), in general, may be a promising part of the solution to the lack of effective structural probe at the molecular scale in LC studies. PMID:25045045

  16. Standardizing the Pre-Licensure Supervision Process: A Commentary on Advocating for Direct Observation of Skills

    ERIC Educational Resources Information Center

    Gray, Neal D.; Erickson, Paul

    2013-01-01

    The present paper advocates for standardized regulations and laws for supervision of pre-licensed counselors in the United States, particularly for direct observation of clinical skills. A review of regulations by the American Counseling Association (ACA) Office of Professional Affairs (2012) reveals that only two states (Arizona and North…

  17. Parallel electric fields in the upward current region of the aurora: Indirect and direct observations

    E-print Network

    Carlson, Charles W.

    Parallel electric fields in the upward current region of the aurora: Indirect and direct current region of the aurora focusing on the structure of electric fields at the boundary between account of the electric fields in the upward current region of the aurora as observed by the Fast Auroral

  18. Direct in Situ Observation of Synergism between Cellulolytic Enzymes during the Biodegradation of Crystalline Cellulose Fibers

    E-print Network

    Dutcher, John

    Direct in Situ Observation of Synergism between Cellulolytic Enzymes during the Biodegradation types of T. reesei cellulolytic enzymes TrCel6A, TrCel7A, and TrCel7Band their mixtures. TrCel6A and Tr. When acting alone on native cellulose fibers, each of the three enzymes is incapable of significant

  19. Systematic Direct Observation of Time on Task as a Measure of Student Engagement

    ERIC Educational Resources Information Center

    Spanjers, Deanna M.; Burns, Matthew K.; Wagner, Angela R.

    2008-01-01

    This study examines the relationship between systematic direct observation (SDO) of time on task (TOT) and student engagement as measured by a self-report task-specific measure. The research questions guiding the study are (a) what is the relationship between SDO of TOT and a self-report measure of student effort, and (b) what is the relationship…

  20. Affective Evaluations of Objects Are Influenced by Observed Gaze Direction and Emotional Expression

    ERIC Educational Resources Information Center

    Bayliss, Andrew P.; Frischen, Alexandra; Fenske, Mark J.; Tipper, Steven P.

    2007-01-01

    Gaze direction signals another person's focus of interest. Facial expressions convey information about their mental state. Appropriate responses to these signals should reflect their combined influence, yet current evidence suggests that gaze-cueing effects for objects near an observed face are not modulated by its emotional expression. Here, we…

  1. Three-Item Direct Observation Screen (TIDOS) for Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Oner, Pinar; Oner, Ozgur; Munir, Kerim

    2014-01-01

    We compared ratings on the Three-Item Direct Observation Screen test for autism spectrum disorders completed by pediatric residents with the Social Communication Questionnaire parent reports as an augmentative tool for improving autism spectrum disorder screening performance. We examined three groups of children (18-60 months) comparable in age…

  2. Direct Observation of the Strong Interaction Between Carbon Nanotubes and Quartz Substrate

    E-print Network

    Liu, Jie

    Direct Observation of the Strong Interaction Between Carbon Nanotubes and Quartz Substrate Lei Ding of uniform single-walled carbon nanotube (SWNT) arrays on a stable temperature (ST)-cut single crystal quartz as increase the SWNT/quartz interaction. Obvious "up-shifts" of G-band frequencies in the Raman spectra have

  3. Direct observations of a medium-intensity inflow into the Baltic Sea

    E-print Network

    Mohrholz, Volker

    Direct observations of a medium-intensity inflow into the Baltic Sea Jü rgen Sellschoppa , Lars a ship cruise into the Arkona Sea (Western Baltic) happened to start just prior to a mediumsize inflow; Water mixing; Salinity stratification; Baltic Sea a) FWG, Klausdorfer Weg 2-24, D-24148 Kiel, Germany b

  4. Considering Systematic Direct Observation after a Century of Research--Commentary on the Special Issue

    ERIC Educational Resources Information Center

    Stichter, Janine P.; Riley-Tillman, T. Chris

    2014-01-01

    Systematic Direct Observation (SDO) has played a pivotal role in the field of Emotional and/or Behavioral Disorders (EBD) since its inception as a key part of understanding more about the behaviors, contexts that impact them, and the effective supports necessary for this population. This methodology is an ongoing charge for everyone. The authors…

  5. Direct observation of the transition from calcite to aragonite growth as induced by abalone shell proteins.

    PubMed Central

    Thompson, J B; Paloczi, G T; Kindt, J H; Michenfelder, M; Smith, B L; Stucky, G; Morse, D E; Hansma, P K

    2000-01-01

    The mixture of EDTA-soluble proteins found in abalone nacre are known to cause the nucleation and growth of aragonite on calcite seed crystals in supersaturated solutions of calcium carbonate. Past atomic force microscope studies of the interaction of these proteins with calcite crystals did not observe this transition because no information about the crystal polymorph on the surface was obtained. Here we have used the atomic force microscope to directly observe changes in the atomic lattice on a calcite seed crystal after the introduction of abalone shell proteins. The observed changes are consistent with a transition to (001) aragonite growth on a (1014) calcite surface. PMID:11106633

  6. Direct observation of size scaling and elastic interaction between nano-scale defects in collision cascades

    NASA Astrophysics Data System (ADS)

    Yi, X.; Sand, A. E.; Mason, D. R.; Kirk, M. A.; Roberts, S. G.; Nordlund, K.; Dudarev, S. L.

    2015-05-01

    Using in situ transmission electron microscopy, we have directly observed nano-scale defects formed in ultra-high-purity tungsten by low-dose high-energy self-ion irradiation at 30 K. At cryogenic temperature lattice defects have reduced mobility, so these microscope observations offer a window on the initial, primary damage caused by individual collision cascade events. Electron microscope images provide direct evidence for a power-law size distribution of nano-scale defects formed in high-energy cascades, with an upper size limit independent of the incident ion energy, as predicted by Sand et al. (EPL, 103 (2013) 46003). Furthermore, the analysis of pair distribution functions of defects observed in the micrographs shows significant intra-cascade spatial correlations consistent with strong elastic interaction between the defects.

  7. A direct observation the asteroid's structure from deep interior to regolith: why and how do it?

    NASA Astrophysics Data System (ADS)

    Herique, A.; Kofman, W. W.

    2013-12-01

    The internal structure of asteroids is still poorly known and has never been measured directly. Our knowledge is relying entirely on inferences from remote sensing observations of the surface, and theoretical modeling. Is the body a monolithic piece of rock or a rubble-pile, an aggregate of boulders held together by gravity and how much porosity it contains, both in the form of micro-scale or macro-scale porosity? What is the typical size of the constituent blocs? Are these blocs homogeneous or heterogeneous? Is the body a defunct or dormant comet and such MBC can become active? The body is covered by a regolith from whose properties remains largely unknown in term of depth, size distribution and spatial variation. Is resulting from fine particles re-accretion or from thermal fracturing? What are its coherent forces? How to model is thermal conductivity while this parameter is so important to estimate Yarkowsky and Yorp effects? Knowing asteroid deep interior and regolith structure is a key point for a better understanding of the asteroid accretion and dynamical evolution. There is no way to determine this from ground-based observation. Radar operating from a spacecraft is the only technique capable of achieving this science objective of characterizing the internal structure and heterogeneity from submetric to global scale for the science benefit as well as for the planetary defence and human exploration. The deep interior structure tomography requires low-frequency radar to penetrate throughout the complete body. The radar wave propagation delay and the received power are related to the complex dielectric permittivity (i.e to the composition and microporosity) and the small scale heterogeneities (scattering losses) while the spatial variation of the signal and the multiple paths provide information on the presence of heterogeneities (variations in composition or porosity), layers, ice lens. A partial coverage will provide "cuts" of the body when a dense coverage will allow a complete tomography. Two instruments concepts can be envisaged: A monostatic radar like Marsis/Mars Express (ESA) that will analyze radar waves transmitted by the orbiter and received after reflection by the asteroid, its surface and its internal structures. A bistatic radar like Consert/Rosetta (ESA that will analyze radar waves transmitted by a lander, propagated through the body and received by the orbiter. Imaging the first ~50 meters of the subsurface with a decimetric resolution to identify layering and to reconnect surface measurement to internal structure requires a higher frequency radar on Orbiter only, like Wisdom developed for ExoMars Rover (ESA) with a frequency ranging from 300 MHz up to 2.7 GHz. This paper reviews the science benefit of direct measurement of asteroid interior. Then radar concepts for both deep interior and near surface sounding and their science return are shown.

  8. Direct laboratory observation of fluid distribution and its influence on acoustic properties of patchy saturated rocks

    NASA Astrophysics Data System (ADS)

    Lebedev, M.; Clennell, B.; Pervukhina, M.; Shulakova, V.; Mueller, T.; Gurevich, B.

    2009-04-01

    Porous rocks in hydrocarbon reservoirs are often saturated with a mixture of two or more fluids. Interpretation of exploration seismograms requires understanding of the relationship between distribution of the fluids patches and acoustic properties of rocks. The sizes of patches as well as their distribution affect significantly the seismic response. If the size of the fluid patch is smaller than the diffusion wavelength then pressure equilibration is achieved and the bulk modulus of the rock saturated with a mixture is defined by the Gassmann equations (Gassmann, 1951) with the saturation-weighted average of the fluid bulk modulus given by Wood's law (Wood, 1955, Mavko et al., 1998). If the fluid patch size is much larger than the diffusion wavelength then there is no pressure communication between different patches. In this case, fluid-flow effects can be neglected and the overall rock may be considered equivalent to an elastic composite material consisting of homogeneous parts whose properties are given by Gassmann theory with Hill's equation for the bulk modulus (Hill, 1963, Mavko et al., 1998). At intermediate values of fluid saturation the velocity-saturation relationship is significantly affected by the fluid patch distribution. In order to get an improved understanding of factors influencing the patch distribution and the resulting seismic wave response we performed simultaneous measurements of P-wave velocities and rock sample CT imaging. The CT imaging allows us to map the fluid distribution inside rock sample during saturation (water imbibition). We compare the experimental results with theoretical predictions. In this paper we will present results of simultaneous measurements of longitudinal wave velocities and imaging mapping of fluid distribution inside rock sample during sample saturation. We will report results of two kinds of experiments: "dynamic" and "quasi static" saturation. In both experiments Casino Cores Otway Basin sandstone, Australia core samples (38 mm in diameter, approximately 60 mm long) were dried in oven under reduced pressure. In dynamic saturation experiments, samples were jacketed in the experimental cell, made from transparent for X-radiation material (PMMA). Distillate water was injected into the sample from the one side. Fluid distribution in such "dynamic" experiment: both spatial and time dependant was measured using X-ray Computer Tomograph (CT) with resolution 0.2 x 0.2 x 1 mm3. Velocities (Vp, and Vs) at ultrasonic frequency of 1 MHz, were measured in the direction perpendicular to initial direction of the fluid flow injection. Sample saturation was estimated from the CT results. In "quasi static" experiments samples were saturated during long period of time (over 2 weeks) to achieve uniform distribution of liquid inside the sample. Saturation was determined by measurement of the weight of water fraction. All experiments were performed at laboratory environments at temperature 25 C. Ultrasonic velocities and fluid saturations were measured simultaneously during water injection into sandstone core samples. The experimental results obtained on low-permeability samples show that at low saturation values the velocity-saturation dependence can be described by the Gassmann-Wood relationship. However, with increasing saturation a sharp increase of P-wave velocity is observed, eventually approaching the Gassmann-Hill relationship. We connect the characteristics of the transition behavior of the velocity-saturation relationships to the increasing size of the patches inside the rock sample. In particular, we show that for relatively large fluid injection rate this transition occurs at smaller degrees of saturation as compared with high injection rate. We model the experimental data using the so-called White model (Toms 2007) that assumes fluid patch distribution as a periodic assemblage of concentric spheres. We can observe reasonable agreement between experimental results and theoretical predictions of White's model. The results illustrate the non

  9. THE STRUCTURE OF A SELF-GRAVITATING PROTOPLANETARY DISK AND ITS IMPLICATIONS FOR DIRECT IMAGING OBSERVATIONS

    SciTech Connect

    Muto, Takayuki

    2011-09-20

    We consider the effects of self-gravity on the hydrostatic balance in the vertical direction of a gaseous disk and discuss the possible signature of the self-gravity that may be captured by direct imaging observations of protoplanetary disks in the future. In this paper, we consider a vertically isothermal disk in order to isolate the effects of self-gravity. The specific disk model we consider in this paper is the one with a radial surface density gap, at which the Toomre's Q-parameter of the disk varies rapidly in the radial direction. We calculate the vertical structure of the disk including the effects of self-gravity. We then calculate the scattered light and the dust thermal emission. We find that if the disk is massive enough and the effects of self-gravity come into play, a weak bump-like structure at the gap edge appears in the near-infrared (NIR) scattered light, while no such bump-like structure is seen in the submillimeter (sub-mm) dust continuum image. The appearance of the bump is caused by the variation of the height of the surface in the NIR wavelength. If such a bump-like feature is detected in future direct imaging observations, combined with sub-mm observations, it will give us useful information about the physical states of the disk.

  10. VERITAS Observations of the Arrival Directions of the Highest Energy Cosmic Rays

    E-print Network

    J. Holder; for the VERITAS Collaboration

    2008-10-02

    The recent discovery by the Pierre Auger collaboration of anisotropy in the arrival directions of the highest energy cosmic rays, correlated with the positions of nearby active galactic nuclei, encourages the search for counterpart TeV gamma-ray emission. Approximately half of the sky viewed by the southern hemisphere Pierre Auger experiment is also visible at reasonable elevations for the northern hemisphere gamma-ray telescope array, VERITAS. We report on first observations by VERITAS of regions associated with the arrival directions of ultra-high energy cosmic ray events.

  11. Unimolecular Thermal Decomposition of Phenol and d5-Phenol: Direct Observation of Cyclopentadiene Formation via Cyclohexadienone

    SciTech Connect

    Scheer, A. M.; Mukarakate, C.; Robichaud, D. J.; Nimlos, M. R.; Carstensen, H. H.; Barney, E. G.

    2012-01-28

    The pyrolyses of phenol and d{sub 5}-phenol (C{sub 6}H{sub 5}OH and C{sub 6}D{sub 5}OH) have been studied using a high temperature, microtubular ({mu}tubular) SiC reactor. Product detection is via both photon ionization (10.487 eV) time-of-flight mass spectrometry and matrix isolation infrared spectroscopy. Gas exiting the heated reactor (375 K-1575 K) is subject to a free expansion after a residence time in the {mu}tubular reactor of approximately 50-100 {micro}s. The expansion from the reactor into vacuum rapidly cools the gas mixture and allows the detection of radicals and other highly reactive intermediates. We find that the initial decomposition steps at the onset of phenol pyrolysis are enol/keto tautomerization to form cyclohexadienone followed by decarbonylation to produce cyclopentadiene; C{sub 6}H{sub 5}OH {yields} c-C{sub 6}H{sub 6} = O {yields} c-C{sub 5}H{sub 6} + CO. The cyclopentadiene loses a H atom to generate the cyclopentadienyl radical which further decomposes to acetylene and propargyl radical; c-C{sub 5}H{sub 6} {yields} c-C{sub 5}H{sub 5} + H {yields} HC {triple_bond} CH + HCCCH{sub 2}. At higher temperatures, hydrogen loss from the PhO-H group to form phenoxy radical followed by CO ejection to generate the cyclopentadienyl radical likely contributes to the product distribution; C{sub 6}H{sub 5}O-H {yields} C{sub 6}H{sub 5}O + H {yields} c-C{sub 5}H{sub 5} + CO. The direct decarbonylation reaction remains an important channel in the thermal decomposition mechanisms of the dihydroxybenzenes. Both catechol (o-HO-C{sub 6}H{sub 4}-OH) and hydroquinone (p-HO-C{sub 6}H{sub 4}-OH) are shown to undergo decarbonylation at the onset of pyrolysis to form hydroxycyclopentadiene. In the case of catechol, we observe that water loss is also an important decomposition channel at the onset of pyrolysis.

  12. Diffusion of a Highly-Charged Supramolecular Assembly: Direct Observation of Ion-Association in Water

    SciTech Connect

    University of California, Berkeley; Lawrence Berkeley National Laboratory; Raymond, Kenneth; Pluth, Michael D.; Tiedemann, Bryan E.F.; van Halbeek, Herman; Nunlist, Rudi; Raymond, Kenneth N.

    2007-10-22

    Understanding the solution behavior of supramolecular assemblies is essential for a full understanding of the formation and chemistry of synthetic host-guest systems. While the interaction between host and guest molecules is generally the focus of mechanistic studies of host-guest complexes, the interaction of the host-guest complex with other species in solution remains largely unknown, although in principle accessible by diffusion studies. Several NMR techniques are available to monitor diffusion and have recently been reviewed. Pulsed gradient spin-echo (PGSE) NMR methods have attracted increasing interest, since they allow diffusion coefficients to be measured with high accuracy; they have been successfully used with observation of {sup 7}Li and {sup 31}P nuclei as well as with {sup 1}H NMR. We report here the direct measurement of diffusion coefficients to observe ion-association interactions by counter cations with a highly-charged supramolecular assembly. Raymond and coworkers have described the design and chemistry of a class of metal-ligand supramolecular assemblies over the past decade. The [Ga{sub 4}L{sub 6}]{sup 12-} (L = 1,5-bis(2,3-dihydroxybenzamido)naphthalene) (1) (Figure 1) assembly has garnered the most attention, with the exploration of the dynamics and mechanism of guest exchange as well as the ability of 1 to achieve either stoichiometric or catalytic reactions inside its interior cavity. Recent studies have revealed the importance of counter cations in solution on the chemistry of 1. During the mechanistic study of the C-H bond activation of aldehydes by [Cp*Ir(PMe{sub 3})(olefin){sup +} {contained_in} 1]{sup 11-} a stepwise guest dissociation mechanism with an ion-paired intermediate was proposed. Similarly, in the mechanism for the hydrolysis of iminium cations generated from the 3-aza Cope rearrangement of enammonium cations in 1, the presence of an exterior ion association was part of the kinetic model. To further substantiate the indirect kinetic evidence for such ion-paired species, we sought to explore the solution behavior of 1 by studying the diffusion of 1 with varying alkali and tetraalkyl ammonium cations. For large molecules in solution, such as synthetic supramolecular assemblies, the diffusion behavior of host and guest molecules can provide valuable information on host-guest interaction. One characteristic feature of a stable host-guest complex is that the host and guest molecules diffuse at the same rate in solution; this has been observed in a number of supramolecular systems. In order to confirm that this system was suitable for study by diffusion NMR spectroscopy, a PGSE-DOSY spectrum was acquired of [NEt{sub 4} {contained_in} 1]{sup 11-} (Figure 2), which shows that the host and guest molecules diffuse at the same rate. Quantitative analysis of the data, from monitoring the integral of host and guest resonances as a function of applied gradient strength, gave identical diffusion coefficients, confirming that the host and guest molecules diffuse together.

  13. Direct Observation of Field and Temperature Induced Domain Replication in Dipolar Coupled Perpendicular Anisotropy Films

    SciTech Connect

    Hauet, T.; Gunther, C.M.; Pfau, B.; Eisebitt, S.; Fischer, P.; Rick, R. L.; Thiele, J.-U.; Hellwig, O.; Schabes, M.E.

    2007-07-01

    Dipolar interactions in a soft/Pd/hard [CoNi/Pd]{sub 30}/Pd/[Co/Pd]{sub 20} multilayer system, where a thick Pd layer between two ferromagnetic units prevents direct exchange coupling, are directly revealed by combining magnetometry and state-of-the-art layer resolving soft x-ray imaging techniques with sub-100-nm spatial resolution. The domains forming in the soft layer during external magnetic field reversal are found to match the domains previously trapped in the hard layer. The low Curie temperature of the soft layer allows varying its intrinsic parameters via temperature and thus studying the competition with dipolar fields due to the domains in the hard layer. Micromagnetic simulations elucidate the role of [CoNi/Pd] magnetization, exchange, and anisotropy in the duplication process. Finally, thermally driven domain replication in remanence during temperature cycling is demonstrated.

  14. Inter-observer reproducibility of back surface topography parameters allowing assessment of scoliotic thoracic gibbosity and comparison with two standard postures.

    PubMed

    de Sèze, M; Randriaminahisoa, T; Gaunelle, A; de Korvin, G; Mazaux, J-M

    2013-12-01

    The objective of this work was to analyze the inter-observer reproducibility of an upright posture designed to bring out the thoracic humps by folding the upper limbs. The effect of this posture on back surface parameters was also compared with two standard radiological postures. A back surface topography was performed on 46 patients (40 girls and 6 boys) with a minimum of 15° Cobb angle on coronal spinal radiographs. Inter-observer reliability was evaluated using the typical error measurement (TEM) and Intraclass Correlation Coefficient (ICC). Variations between postures were assessed using a Student's t test. The inter-observer reproducibility is good enough for the three postures. The proposed posture leads to significant changes in the sagittal plane as well as in the identification of thoracic humps. This study shows the reproducibility of the proposed posture in order to explore the thoracic humps and highlights its relevance to explore scoliosis with back surface topography systems. PMID:24238970

  15. Gravity Waves Generated by Convection: A New Idealized Model Tool and Direct Validation with Satellite Observations

    NASA Astrophysics Data System (ADS)

    Alexander, M. Joan; Stephan, Claudia

    2015-04-01

    In climate models, gravity waves remain too poorly resolved to be directly modelled. Instead, simplified parameterizations are used to include gravity wave effects on model winds. A few climate models link some of the parameterized waves to convective sources, providing a mechanism for feedback between changes in convection and gravity wave-driven changes in circulation in the tropics and above high-latitude storms. These convective wave parameterizations are based on limited case studies with cloud-resolving models, but they are poorly constrained by observational validation, and tuning parameters have large uncertainties. Our new work distills results from complex, full-physics cloud-resolving model studies to essential variables for gravity wave generation. We use the Weather Research Forecast (WRF) model to study relationships between precipitation, latent heating/cooling and other cloud properties to the spectrum of gravity wave momentum flux above midlatitude storm systems. Results show the gravity wave spectrum is surprisingly insensitive to the representation of microphysics in WRF. This is good news for use of these models for gravity wave parameterization development since microphysical properties are a key uncertainty. We further use the full-physics cloud-resolving model as a tool to directly link observed precipitation variability to gravity wave generation. We show that waves in an idealized model forced with radar-observed precipitation can quantitatively reproduce instantaneous satellite-observed features of the gravity wave field above storms, which is a powerful validation of our understanding of waves generated by convection. The idealized model directly links observations of surface precipitation to observed waves in the stratosphere, and the simplicity of the model permits deep/large-area domains for studies of wave-mean flow interactions. This unique validated model tool permits quantitative studies of gravity wave driving of regional circulation and provides a new method for future development of realistic convective gravity wave parameterizations.

  16. Metabolic profiling of plant extracts using direct-injection electrospray ionization mass spectrometry allows for high-throughput phenotypic characterization according to genetic and environmental effects.

    PubMed

    García-Flores, Martín; Juárez-Colunga, Sheila; García-Casarrubias, Adrián; Trachsel, Samuel; Winkler, Robert; Tiessen, Axel

    2015-01-28

    In comparison to the exponential increase of genotyping methods, phenotyping strategies are lagging behind in agricultural sciences. Genetic improvement depends upon the abundance of quantitative phenotypic data and the statistical partitioning of variance into environmental, genetic, and random effects. A metabolic phenotyping strategy was adapted to increase sample throughput while saving reagents, reducing cost, and simplifying data analysis. The chemical profiles of stem extracts from maize plants grown under low nitrogen (LN) or control trial (CT) were analyzed using optimized protocols for direct-injection electrospray ionization mass spectrometry (DIESI-MS). Specific ions significantly decreased or increased because of environmental (LN versus CT) or genotypic effects. Biochemical profiling with DIESI-MS had a superior cost-benefit compared to other standard analytical technologies (e.g., ultraviolet, near-infrared reflectance spectroscopy, high-performance liquid chromatography, and gas chromatography with flame ionization detection) routinely used for plant breeding. The method can be successfully applied in maize, strawberry, coffee, and other crop species. PMID:25588121

  17. Validation of simulated flow direction and hydraulic gradients with hydraulic head observations using open source GIS

    NASA Astrophysics Data System (ADS)

    Vandersteen, Katrijn; Rogiers, Bart; Gedeon, Matej

    2015-04-01

    It is recommended to check hydraulic gradients and flow directions predicted by a groundwater flow model that is calibrated solely with hydraulic head observations. It has been demonstrated in literature that substantial errors can be made when the model is not calibrated on these state variables. Therefore, in this work, we perform a validation of a steady-state groundwater flow model, representing part of the Neogene aquifer (60 km2) in Belgium. This model was developed and calibrated solely on groundwater head measurements, in the framework of the environmental impact assessment of the near surface repository for low- and intermediate-level short-lived waste, realized by ONDRAF/NIRAS at Dessel, Belgium. Horizontal flow directions, horizontal and vertical gradients for the entire area of the groundwater model were estimated from measurements at shallow monitoring wells within the groundwater flow model domain, and compared to the flow directions and vertical gradients predicted by the model. For obtaining horizontal flow directions and gradients, triangulation of groundwater levels was performed for combinations of three neighboring hydraulic head observations in the same hydrogeological layer within the model. The simulated equivalents at the same monitoring wells were used to repeat the same methodology, and calculate flow direction components. This analysis was performed in SAGA GIS and was visualized through QGIS. Comparison of the flow directions and flow gradients obtained from measurements and simulations gives an indication on the model performance. The calculations were performed for three sandy hydrogeological units used in the model. A similar procedure was performed for the vertical hydraulic head gradients, where any combination of two hydraulic head observations at the same location but at different levels within the aquifer were used to validate the vertical gradients predicted by the model. Besides model validation on average hydraulic heads, the variability of flow direction and hydraulic gradients in time was checked, by using the actually measured monthly time series, to verify the applicability of the steady-state modelling approach. This basic assessment of flow directions and gradients using open source GIS can be used to identify potential areas of interest, were more detailed investigations would be recommended.

  18. Direct spectroscopic observation of a shallow hydrogenlike donor state in insulating SrTiO3.

    PubMed

    Salman, Z; Prokscha, T; Amato, A; Morenzoni, E; Scheuermann, R; Sedlak, K; Suter, A

    2014-10-10

    We present a direct spectroscopic observation of a shallow hydrogenlike muonium state in SrTiO(3) which confirms the theoretical prediction that interstitial hydrogen may act as a shallow donor in this material. The formation of this muonium state is temperature dependent and appears below ? 70K. From the temperature dependence we estimate an activation energy of ? 50 meV in the bulk and ? 23 meV near the free surface. The field and directional dependence of the muonium precession frequencies further supports the shallow impurity state with a rare example of a fully anisotropic hyperfine tensor. From these measurements we determine the strength of the hyperfine interaction and propose that the muon occupies an interstitial site near the face of the oxygen octahedron in SrTiO(3). The observed shallow donor state provides new insight for tailoring the electronic and optical properties of SrTiO(3)-based oxide interface systems. PMID:25375730

  19. Direct observation of depth-dependent atomic displacements associated with dislocations in gallium nitride.

    PubMed

    Lozano, J G; Yang, H; Guerrero-Lebrero, M P; D'Alfonso, A J; Yasuhara, A; Okunishi, E; Zhang, S; Humphreys, C J; Allen, L J; Galindo, P L; Hirsch, P B; Nellist, P D

    2014-09-26

    We demonstrate that the aberration-corrected scanning transmission electron microscope has a sufficiently small depth of field to observe depth-dependent atomic displacements in a crystal. The depth-dependent displacements associated with the Eshelby twist of dislocations in GaN normal to the foil with a screw component of the Burgers vector are directly imaged. We show that these displacements are observed as a rotation of the lattice between images taken in a focal series. From the sense of the rotation, the sign of the screw component can be determined. PMID:25302902

  20. Earth Science System of the Future: Observing, Processing, and Delivering Data Products Directly to Users

    NASA Technical Reports Server (NTRS)

    Crisp, David; Komar, George (Technical Monitor)

    2001-01-01

    Advancement of our predictive capabilities will require new scientific knowledge, improvement of our modeling capabilities, and new observation strategies to generate the complex data sets needed by coupled modeling networks. New observation strategies must support remote sensing from a variety of vantage points and will include "sensorwebs" of small satellites in low Earth orbit, large aperture sensors in Geostationary orbits, and sentinel satellites at L1 and L2 to provide day/night views of the entire globe. Onboard data processing and high speed computing and communications will enable near real-time tailoring and delivery of information products (i.e., predictions) directly to users.

  1. Direct observation of charge mediated lattice distortions in complex oxide solid solutions

    SciTech Connect

    Sang, Xiahan; Grimley, Everett D.; Niu, Changning; Irving, Douglas L.; LeBeau, James M.

    2015-02-09

    Using aberration corrected scanning transmission electron microscopy combined with advanced imaging methods, we directly observe atom column specific, picometer-scale displacements induced by local chemistry in a complex oxide solid solution. Displacements predicted from density functional theory were found to correlate with the observed experimental trends. Further analysis of bonding and charge distribution was used to clarify the mechanisms responsible for the detected structural behavior. By extending the experimental electron microscopy measurements to previously inaccessible length scales, we identified correlated atomic displacements linked to bond differences within the complex oxide structure.

  2. Direct observation of charge inversion by multivalent ions as a universal electrostatic phenomenon.

    PubMed

    Besteman, K; Zevenbergen, M A G; Heering, H A; Lemay, S G

    2004-10-22

    We have directly observed reversal of the polarity of charged surfaces in water upon the addition of trivalent and quadrivalent ions using atomic force microscopy. The bulk concentration of multivalent ions at which charge inversion reversibly occurs depends only very weakly on the chemical composition, surface structure, size, and lipophilicity of the ions, but is very sensitive to their valence. These results support the theoretical proposal that spatial correlations between ions are the driving mechanism behind charge inversion. PMID:15525062

  3. Three-dimensional atomic force microscopy: interaction force vector by direct observation of tip trajectory.

    PubMed

    Sigdel, Krishna P; Grayer, Justin S; King, Gavin M

    2013-11-13

    The prospect of a robust three-dimensional atomic force microscope (AFM) holds significant promise in nanoscience. Yet, in conventional AFM, the tip-sample interaction force vector is not directly accessible. We scatter a focused laser directly off an AFM tip apex to rapidly and precisely measure the tapping tip trajectory in three-dimensional space. This data also yields three-dimensional cantilever spring constants, effective masses, and hence, the tip-sample interaction force components via Newton's second law. Significant lateral forces representing 49 and 13% of the normal force (Fz = 152 ± 17 pN) were observed in common tapping mode conditions as a silicon tip intermittently contacted a glass substrate in aqueous solution; as a consequence, the direction of the force vector tilted considerably more than expected. When addressing the surface of a lipid bilayer, the behavior of the force components differed significantly from that observed on glass. This is attributed to the lateral mobility of the lipid membrane coupled with its elastic properties. Direct access to interaction components Fx, Fy, and Fz provides a more complete view of tip dynamics that underlie force microscope operation and can form the foundation of a three-dimensional AFM in a plurality of conditions. PMID:24099456

  4. Increasing Reliability of Direct Observation Measurement Approaches in Emotional and/or Behavioral Disorders Research Using Generalizability Theory

    ERIC Educational Resources Information Center

    Gage, Nicholas A.; Prykanowski, Debra; Hirn, Regina

    2014-01-01

    Reliability of direct observation outcomes ensures the results are consistent, dependable, and trustworthy. Typically, reliability of direct observation measurement approaches is assessed using interobserver agreement (IOA) and the calculation of observer agreement (e.g., percentage of agreement). However, IOA does not address intraobserver…

  5. Rationale, design, and sample characteristics of a randomized controlled trial of directly observed antiretroviral therapy delivered in methadone clinics

    PubMed Central

    Berg, Karina M.; Mouriz, Jennifer; Li, Xuan; Duggan, Elise; Goldberg, Uri; Arnsten, Julia H.

    2009-01-01

    Background Directly observed therapy (DOT) programs for HIV treatment have demonstrated feasibility, acceptability, and improved viral suppression, but few have been rigorously tested. We describe a randomized controlled trial testing the efficacy of an antiretroviral DOT program in methadone maintenance clinics. Our objective was to determine if DOT is more efficacious than self-administered antiretroviral therapy for reducing HIV viral load, improving adherence, and reducing drug resistance among opioid dependent drug users receiving methadone treatment. Methods Participants were randomized to treatment as usual (TAU) or antiretroviral DOT for the 24-week intervention. TAU participants received standard adherence counseling, and DOT participants received standard adherence counseling plus directly observed antiretroviral therapy, which was delivered at the same time as they received daily methadone. Assessments occurred at baseline, weekly for 8 weeks, and then monthly for 4 months. Our primary outcomes were between group changes from baseline to the end of the intervention in: HIV viral load, antiretroviral adherence, and number of viral mutations. Results Between June 2004 and August 2007, we screened 3,231 methadone maintained patients and enrolled 77; 39 participants were randomized to DOT and 38 to TAU. 65 completed the 24-week intervention. Conclusions Our trial will allow rigorous evaluation of the efficacy of directly observed antiretroviral therapy delivered in methadone clinics for improving adherence and clinical outcomes. This detailed description of trial methodology can serve as a template for the development of future DOT programs and can guide protocols for studies among HIV-infected drug users receiving methadone for opioid dependence. PMID:19505589

  6. Warming experiments elucidate the drivers of observed directional changes in tundra vegetation

    PubMed Central

    Hollister, Robert D; May, Jeremy L; Kremers, Kelseyann S; Tweedie, Craig E; Oberbauer, Steven F; Liebig, Jennifer A; Botting, Timothy F; Barrett, Robert T; Gregory, Jessica L

    2015-01-01

    Few studies have clearly linked long-term monitoring with in situ experiments to clarify potential drivers of observed change at a given site. This is especially necessary when findings from a site are applied to a much broader geographic area. Here, we document vegetation change at Barrow and Atqasuk, Alaska, occurring naturally and due to experimental warming over nearly two decades. An examination of plant cover, canopy height, and community indices showed more significant differences between years than due to experimental warming. However, changes with warming were more consistent than changes between years and were cumulative in many cases. Most cases of directional change observed in the control plots over time corresponded with a directional change in response to experimental warming. These included increases in canopy height and decreases in lichen cover. Experimental warming resulted in additional increases in evergreen shrub cover and decreases in diversity and bryophyte cover. This study suggests that the directional changes occurring at the sites are primarily due to warming and indicates that further changes are likely in the next two decades if the regional warming trend continues. These findings provide an example of the utility of coupling in situ experiments with long-term monitoring to accurately document vegetation change in response to global change and to identify the underlying mechanisms driving observed changes. PMID:26140204

  7. Warming experiments elucidate the drivers of observed directional changes in tundra vegetation.

    PubMed

    Hollister, Robert D; May, Jeremy L; Kremers, Kelseyann S; Tweedie, Craig E; Oberbauer, Steven F; Liebig, Jennifer A; Botting, Timothy F; Barrett, Robert T; Gregory, Jessica L

    2015-05-01

    Few studies have clearly linked long-term monitoring with in situ experiments to clarify potential drivers of observed change at a given site. This is especially necessary when findings from a site are applied to a much broader geographic area. Here, we document vegetation change at Barrow and Atqasuk, Alaska, occurring naturally and due to experimental warming over nearly two decades. An examination of plant cover, canopy height, and community indices showed more significant differences between years than due to experimental warming. However, changes with warming were more consistent than changes between years and were cumulative in many cases. Most cases of directional change observed in the control plots over time corresponded with a directional change in response to experimental warming. These included increases in canopy height and decreases in lichen cover. Experimental warming resulted in additional increases in evergreen shrub cover and decreases in diversity and bryophyte cover. This study suggests that the directional changes occurring at the sites are primarily due to warming and indicates that further changes are likely in the next two decades if the regional warming trend continues. These findings provide an example of the utility of coupling in situ experiments with long-term monitoring to accurately document vegetation change in response to global change and to identify the underlying mechanisms driving observed changes. PMID:26140204

  8. Direct observation of imprinted antiferromagnetic vortex state in CoO/Fe/Ag(001) disks

    SciTech Connect

    Wu, J.; Carlton, D.; Park, J. S.; Meng, Y.; Arenholz, E.; Doran, A.; Young, A.T.; Scholl, A.; Hwang, C.; Zhao, H. W.; Bokor, J.; Qiu, Z. Q.

    2010-12-21

    In magnetic thin films, a magnetic vortex is a state in which the magnetization vector curls around the center of a confined structure. A vortex state in a thin film disk, for example, is a topological object characterized by the vortex polarity and the winding number. In ferromagnetic (FM) disks, these parameters govern many fundamental properties of the vortex such as its gyroscopic rotation, polarity reversal, core motion, and vortex pair excitation. However, in antiferromagnetic (AFM) disks, though there has been indirect evidence of the vortex state through observations of the induced FM-ordered spins in the AFM disk, they have never been observed directly in experiment. By fabricating single crystalline NiO/Fe/Ag(001) and CoO/Fe/Ag(001) disks and using X-ray Magnetic Linear Dichroism (XMLD), we show direct observation of the vortex state in an AFM disk of AFM/FM bilayer system. We observe that there are two types of AFM vortices, one of which has no analog in FM structures. Finally, we show that a frozen AFM vortex can bias a FM vortex at low temperature.

  9. Direct observation of syringeal muscle function in songbirds and a parrot.

    PubMed

    Larsen, Ole Naesbye; Goller, Franz

    2002-01-01

    The role of syringeal muscles in controlling the aperture of the avian vocal organ, the syrinx, was evaluated directly for the first time by observing and filming through an endoscope while electrically stimulating different muscle groups of anaesthetised birds. In songbirds (brown thrashers, Toxostoma rufum, and cardinals, Cardinalis cardinalis), direct observations of the biomechanical effects of contraction largely confirm the functions of the intrinsic syringeal muscles proposed from indirect studies. Contraction of the dorsal muscles, m. syringealis dorsalis (dS) and m. tracheobronchialis dorsalis, constricts the syringeal lumen and thus reduces airflow by adducting connective tissue masses, the medial (ML) and lateral (LL) labia. Activity of the medial portion of the dS appears to affect the position of the ML and, consequently, plays a previously undescribed role in aperture control. Under the experimental conditions used in this study, full constriction of the syringeal lumen could not be achieved by stimulating adductor muscles. Full closure may require simultaneous activation of extrinsic syringeal muscles or the supine positioning of the bird may have exerted excessive tension on the syrinx. Contraction of m. tracheobronchialis ventralis enlarges the syringeal lumen and thus increases airflow by abducting the LL but does not affect the ML. The largest syringeal muscle, m. syringealis ventralis, plays a minor role, if any, in direct aperture control and thus in gating airflow. In parrots (cockatiels, Nymphicus hollandicus), direct observations show that even during quiet respiration the lateral tympaniform membranes (LTMs) are partially adducted into the tracheal lumen to form a narrow slot. Contraction of the superficial intrinsic muscle, m. syringealis superficialis, adducts the LTMs further into the tracheal lumen but does not close the syringeal aperture fully. The intrinsic deep muscle, m. syringealis profundus, abducts the LTMs through cranio-lateral movement of a paired, protruding half-ring. The weakly developed extrinsic m. sternotrachealis seems to increase tension in the ipsilateral LTM but does not move it in or out of the syringeal lumen. PMID:11818409

  10. Retrieval and validation of global, direct, and diffuse irradiance derived from SEVIRI satellite observations

    NASA Astrophysics Data System (ADS)

    Greuell, W.; Meirink, J. F.; Wang, P.

    2013-03-01

    AbstractThis paper discusses Surface Insolation under Clear and Cloudy skies derived from SEVIRI imagery (SICCS), a physics-based, empirically adjusted algorithm developed for estimation of surface solar irradiance from satellite data. Its most important input are a cloud mask product and cloud properties derived from Meteosat/Spinning Enhanced Visible and Infrared Imager (SEVIRI) <span class="hlt">observations</span>. These <span class="hlt">observations</span> set the characteristics of the output, namely, a temporal resolution of 15 min, a nadir spatial resolution of 3 × 3 km2, the period from January 2004 until at least November 2012, and the domain equal to most of the Meteosat disc. SICCS computes global, <span class="hlt">direct</span>, and diffuse irradiance separately. <span class="hlt">Direct</span> irradiance for cloudy skies is estimated with an empirical method. Hourly means retrieved with SICCS were validated with data from eight Baseline Surface Radiation Network stations for the year 2006. We found median values of the station biases of +6 W/m2 (+5%) for <span class="hlt">direct</span> irradiance, +1 W/m2 (+1%) for diffuse irradiance, and +7 W/m2 (+2%) for global irradiance. Replacing the three-hourly aerosol optical thickness input by monthly means introduces considerable additional biases in the clear-sky <span class="hlt">direct</span> (-6%) and diffuse (+26%) irradiances. The performance of SICCS does not degrade when snow covers the surface. Biases do not vary with cloud optical thickness and cloud particle radius. However, the bias in global transmissivity tends to decrease with increasing cloud heterogeneity, and the bias in <span class="hlt">direct</span> transmissivity is a function of the solar zenith angle. We discuss why satellite retrieval of surface solar irradiance is relatively successful.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21690824','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21690824"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the microstructure in cluster glass compound U(2)IrSi(3).</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yubuta, K; Yamamura, T; Shiokawa, Y</p> <p>2006-07-01</p> <p>We have examined the structure of a U(2)IrSi(3) compound exhibiting ferromagnetic cluster glass behaviour by means of electron diffraction <span class="hlt">observation</span> and high-resolution electron microscopy. The structure of U(2)IrSi(3) has been proposed as a new one of the U(2)RuSi(3)-type with a short-range ordered double stacking sequence of the U(2)RuSi(3)-type structure along the c-axis, and long-range ordered atomic arrangements in the a-b plane. The calculated patterns reproduce the characteristic features of <span class="hlt">observed</span> electron patterns well. The Fourier-filtered high-resolution image clearly exhibits a micro-domain structure, which is considered to relate <span class="hlt">directly</span> to the origin of the <span class="hlt">observed</span> cluster glass behaviour in U(2)IrSi(3). PMID:21690824</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.rsmas.miami.edu/assets/pdfs/green/recycling-program-link.pdf','EPRINT'); return false;" href="http://www.rsmas.miami.edu/assets/pdfs/green/recycling-program-link.pdf"><span id="translatedtitle">RECYCLING PROGRAM TYPE LOCATION <span class="hlt">ALLOWED</span> NOT <span class="hlt">ALLOWED</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Miami, University of</p> <p></p> <p>RECYCLING PROGRAM TYPE LOCATION <span class="hlt">ALLOWED</span> NOT <span class="hlt">ALLOWED</span> Batteries, toner, ink cartridges & cell phones and recycling is an important part of that effort. Below is a guide to on-campus recycling at RSMAS: Visit http://www.rsmas.miami.edu/msgso/ for map of recycling bin locations. NOTE: This is not an exhaustive list. If unauthorized items are found</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1505.03117v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1505.03117v1"><span id="translatedtitle">A General Analysis of <span class="hlt">Direct</span> Dark Matter Detection: From Microphysics to <span class="hlt">Observational</span> Signatures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>James B. Dent; Lawrence M. Krauss; Jayden L. Newstead; Subir Sabharwal</p> <p>2015-05-12</p> <p>Beginning with a set of simplified models for spin-0, spin-$\\half$, and spin-1 dark matter candidates using completely general Lorentz invariant and renormalizable Lagrangians, we derive the full set of non-relativistic operators and nuclear matrix elements relevant for <span class="hlt">direct</span> detection of dark matter, and use these to calculate rates and recoil spectra for scattering on various target nuclei. This <span class="hlt">allows</span> us to explore what high energy physics constraints might be obtainable from <span class="hlt">direct</span> detection experiments, what degeneracies exist, which operators are ubiquitous and which are unlikely or sub-dominant. We find that there are operators which are common to all spins as well operators which are unique to spin-$\\half$ and spin-1 and elucidate two new operators which have not been previously considered. In addition we demonstrate how recoil energy spectra can distinguish fundamental microphysics if multiple target nuclei are used. Our work provides a complete roadmap for taking generic fundamental dark matter theories and calculating rates in <span class="hlt">direct</span> detection experiments. This provides a useful guide for experimentalists designing experiments and theorists developing new dark matter models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4316871','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4316871"><span id="translatedtitle">Capturing the complexity of first opinion small animal consultations using <span class="hlt">direct</span> <span class="hlt">observation</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Robinson, N. J.; Brennan, M. L.; Cobb, M.; Dean, R. S.</p> <p>2015-01-01</p> <p>Various different methods are currently being used to capture data from small animal consultations. The aim of this study was to develop a tool to record detailed data from consultations by <span class="hlt">direct</span> <span class="hlt">observation</span>. A second aim was to investigate the complexity of the consultation by examining the number of problems discussed per patient. A data collection tool was developed and used during <span class="hlt">direct</span> <span class="hlt">observation</span> of small animal consultations in eight practices. Data were recorded on consultation type, patient signalment and number of problems discussed. During 16?weeks of data collection, 1901 patients were presented. Up to eight problems were discussed for some patients; more problems were discussed during preventive medicine consultations than during first consultations (P<0.001) or revisits (P<0.001). Fewer problems were discussed for rabbits than cats (P<0.001) or dogs (P<0.001). Age was positively correlated with discussion of specific health problems and negatively correlated with discussion of preventive medicine. Consultations are complex with multiple problems frequently discussed, suggesting comorbidity may be common. Future research utilising practice data should consider how much of this complexity needs to be captured, and use appropriate methods accordingly. The findings here have implications for <span class="hlt">directing</span> research and education as well as application in veterinary practice. PMID:25262057</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4431344','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4431344"><span id="translatedtitle">Investigating common clinical presentations in first opinion small animal consultations using <span class="hlt">direct</span> <span class="hlt">observation</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Robinson, N. J.; Dean, R. S.; Cobb, M.; Brennan, M. L.</p> <p>2015-01-01</p> <p>Understanding more about the clinical presentations encountered in veterinary practice is vital in <span class="hlt">directing</span> research towards areas relevant to practitioners. The aim of this study was to describe all problems discussed during a convenience sample of consultations using a <span class="hlt">direct</span> <span class="hlt">observation</span> method. A data collection tool was used to gather data by <span class="hlt">direct</span> <span class="hlt">observation</span> during small animal consultations at eight sentinel practices. Data were recorded for all presenting and non-presenting specific health problems discussed. A total of 1901 patients were presented with 3206 specific health problems discussed. Clinical presentation varied widely between species and between presenting and non-presenting problems. Skin lump, vomiting and inappetence were the most common clinical signs reported by the owner while overweight/obese, dental tartar and skin lump were the most common clinical examination findings. Skin was the most frequently affected body system overall followed by non-specific problems then the gastrointestinal system. Consultations are complex, with a diverse range of different clinical presentations seen. Considering the presenting problem only may give an inaccurate view of the veterinary caseload, as some common problems are rarely the reason for presentation. Understanding the common diagnoses made is the next step and will help to further focus questions for future research. PMID:25564472</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010054945','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010054945"><span id="translatedtitle">Apparatus for <span class="hlt">Direct</span> Optical Fiber Through-Lens Illumination of Microscopy or <span class="hlt">Observational</span> Objects</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kadogawa, Hiroshi (Inventor)</p> <p>2001-01-01</p> <p>In one embodiment of the invention, a microscope or other <span class="hlt">observational</span> apparatus, comprises a hollow tube, a lens mounted to the tube, a light source and at least one flexible optical fiber having an input end and an output end. The input end is positioned to receive light from the light source, and the output end is positioned within the tube so as to <span class="hlt">directly</span> project light along a straight path to the lens to illuminate an object to be viewed. The path of projected light is uninterrupted and free of light deflecting elements. By passing the light through the lens, the light can be diffused or otherwise defocused to provide more uniform illumination across the surface of the object, increasing the quality of the image of the object seen by the viewer. The <span class="hlt">direct</span> undeflected and uninterrupted projection of light, without change of <span class="hlt">direction</span>, eliminates the need for light-deflecting elements, such as beam-splitters, mirrors, prisms, or the like, to <span class="hlt">direct</span> the projected light towards the object.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1158478','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1158478"><span id="translatedtitle">In Situ <span class="hlt">Observation</span> of <span class="hlt">Directed</span> Nanoparticle Aggregation During the Synthesis of Ordered Nanoporous Metal in Soft Templates</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Parent, Lucas R.; Robinson, David B.; Cappillino, Patrick J.; Hartnett, Ryan J.; Abellan, Patricia; Evans, James E.; Browning, Nigel D.; Arslan, Ilke</p> <p>2014-01-17</p> <p>The prevalent approach to developing new nanomaterials is a trial-and-error process of iteratively altering synthesis procedures and then characterizing the resulting nanostructures. This is fundamentally limited in that the growth processes that occur during synthesis can be inferred only from the final synthetic structure. <span class="hlt">Directly</span> <span class="hlt">observing</span> real-time nanomaterial growth provides unprecedented insight into the relationship between synthesis conditions and product evolution and facilitates a mechanistic approach to nanomaterial development. Here, we use in situ liquid-stage scanning transmission electron microscopy to <span class="hlt">observe</span> the growth of mesoporous palladium in a solvated block copolymer (BCP) template under various synthesis conditions, and we ultimately determined a refined synthesis procedure that yields extended structures with ordered pores. We found that after sufficient drying time of the casting solvent (tetrahydrofuran, THF), the BCP assembles into a rigid, cylindrical micelle array with a high degree of short-range order but poor long-range order. Upon slowing the THF evaporation rate using a solvent-vapor anneal step, the long-range order was greatly improved. The electron beam induces nucleation of small particles in the aqueous phase around the micelles. The small particles then flocculate and grow into denser structures that surround, but do not overgrow, the micelles, forming an ordered mesoporous structure. The microscope <span class="hlt">observations</span> revealed that pore disorder can be addressed prior to metal reduction and is not invariably induced by the Pd growth process itself, <span class="hlt">allowing</span> for more rapid optimization of the synthetic method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ACPD....9.7707B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ACPD....9.7707B"><span id="translatedtitle">Aerosol characterization in Northern Africa, Northeastern Atlantic, Mediterranean Basin and Middle East from <span class="hlt">direct</span>-sun AERONET <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Basart, S.; Pérez, C.; Cuevas, E.; Baldasano, J. M.; Gobbi, G. P.</p> <p>2009-03-01</p> <p>We provide an atmospheric aerosol characterization for North Africa, Northeastern Atlantic, Mediterranean and Middle East based on the analysis of quality-assured <span class="hlt">direct</span>-sun <span class="hlt">observations</span> of 39 stations of the AErosol RObotic NETwork (AERONET) which include at least an annual cycle within the 1994-2007 period. We extensively test and apply the recently introduced graphical method of Gobbi and co-authors in order to track and discriminate different aerosol types and quantify the contribution of mineral dust. The method relies on the combined analysis of the Ångstrøm exponent (?) and its spectral curvature. Plotting data in these coordinates <span class="hlt">allows</span> to infer aerosol fine mode size (Rf) and fractional contribution (?) to total Aerosol Optical Depth (AOD) and separate AOD growth due to fine-mode aerosol humidification and/or coagulation from AOD growth due to the increase in coarse particles or cloud contamination. Our results confirm the robustness of this graphical method. Large mineral dust is the most important constituent in Northern Africa and Middle East; and under specific meteorological conditions, its transport to Europe is <span class="hlt">observed</span> from spring to autumn. Small pollution particles are abundant in sites close to urban and industrial areas of Continental and Eastern Europe and Middle East; as well as, important contributions of biomass burning are <span class="hlt">observed</span> in the sub-Sahel region in winter. Dust is usually found to mix with these fine, pollution aerosols.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26578164','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26578164"><span id="translatedtitle">Not seeing or feeling is still believing: conscious and non-conscious pain modulation after <span class="hlt">direct</span> and <span class="hlt">observational</span> learning.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Egorova, Natalia; Park, Joel; Orr, Scott P; Kirsch, Irving; Gollub, Randy L; Kong, Jian</p> <p>2015-01-01</p> <p>Our experience with the world is shaped not only <span class="hlt">directly</span> through personal exposure but also indirectly through <span class="hlt">observing</span> others and learning from their experiences. Using a conditioning paradigm, we investigated how <span class="hlt">directly</span> and <span class="hlt">observationally</span> learned information can affect pain perception, both consciously and non-consciously. Differences between <span class="hlt">direct</span> and <span class="hlt">observed</span> cues were manifest in higher pain ratings and larger skin conductance responses to <span class="hlt">directly</span> experienced cues. However, the pain modulation effects produced by conditioning were of comparable magnitude for <span class="hlt">direct</span> and <span class="hlt">observational</span> learning. These results suggest that social <span class="hlt">observation</span> can induce positive and negative pain modulation. Importantly, the fact that cues learned by <span class="hlt">observation</span> and activated non-consciously still produced a robust conditioning effect that withstood extinction highlights the role of indirect exposure in placebo and nocebo effects. PMID:26578164</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4649469','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4649469"><span id="translatedtitle">Not seeing or feeling is still believing: conscious and non-conscious pain modulation after <span class="hlt">direct</span> and <span class="hlt">observational</span> learning</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Egorova, Natalia; Park, Joel; Orr, Scott P.; Kirsch, Irving; Gollub, Randy L.; Kong, Jian</p> <p>2015-01-01</p> <p>Our experience with the world is shaped not only <span class="hlt">directly</span> through personal exposure but also indirectly through <span class="hlt">observing</span> others and learning from their experiences. Using a conditioning paradigm, we investigated how <span class="hlt">directly</span> and <span class="hlt">observationally</span> learned information can affect pain perception, both consciously and non-consciously. Differences between <span class="hlt">direct</span> and <span class="hlt">observed</span> cues were manifest in higher pain ratings and larger skin conductance responses to <span class="hlt">directly</span> experienced cues. However, the pain modulation effects produced by conditioning were of comparable magnitude for <span class="hlt">direct</span> and <span class="hlt">observational</span> learning. These results suggest that social <span class="hlt">observation</span> can induce positive and negative pain modulation. Importantly, the fact that cues learned by <span class="hlt">observation</span> and activated non-consciously still produced a robust conditioning effect that withstood extinction highlights the role of indirect exposure in placebo and nocebo effects. PMID:26578164</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..MAR.Q7015K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..MAR.Q7015K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Chiral Topological Solitons in 1D Charge-Density Waves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Tae-Hwan; Cheon, Sangmo; Lee, Sung-Hoon; Yeom, Han Woong</p> <p>2015-03-01</p> <p>Macroscopic and classical solitons are easily and ubiquitously found, from tsunami to blood pressure pulses, but those in microscopic scale are hard to <span class="hlt">observe</span>. While the existence of such topological solitons were predicted theoretically and evidenced indirectly by the transport and infrared spectroscopy measurements, the <span class="hlt">direct</span> <span class="hlt">observation</span> has been hampered by their high mobility and small dimension. In this talk, we show <span class="hlt">direct</span> <span class="hlt">observation</span> of topological solitons in the quasi-1D charge-density wave (CDW) ground state of indium atomic wires, which are consisting of interacting double Peierls chains. Such solitons exhibit a characteristic spatial variation of the CDW amplitudes as expected from the electronic structure. Furthermore, these solitons have an exotic hidden topology originated by topologically different 4-fold degenerate CDW ground states. Their exotic topology leads to the chirality of 1D topological solitons through interaction between two solitons in the double Peierls chains. Detailed scanning tunneling microscopy and spectroscopy reveal their chiral nature at the atomic scale. This work paves the avenue toward the microscopic exploitation of the peculiar properties of nanoscale chiral solitons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26065925','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26065925"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Wet Biological Samples by Graphene Liquid Cell Transmission Electron Microscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Park, Jungwon; Park, Hyesung; Ercius, Peter; Pegoraro, Adrian F; Xu, Chen; Kim, Jin Woong; Han, Sang Hoon; Weitz, David A</p> <p>2015-07-01</p> <p>Recent development of liquid phase transmission electron microscopy (TEM) enables the study of specimens in wet ambient conditions within a liquid cell; however, <span class="hlt">direct</span> structural <span class="hlt">observation</span> of biological samples in their native solution using TEM is challenging since low-mass biomaterials embedded in a thick liquid layer of the host cell demonstrate low contrast. Furthermore, the integrity of delicate wet samples is easily compromised during typical sample preparation and TEM imaging. To overcome these limitations, we introduce a graphene liquid cell (GLC) using multilayer graphene sheets to reliably encapsulate and preserve biological samples in a liquid for TEM <span class="hlt">observation</span>. We achieve nanometer scale spatial resolution with high contrast using low-dose TEM at room temperature, and we use the GLC to <span class="hlt">directly</span> <span class="hlt">observe</span> the structure of influenza viruses in their native buffer solution at room temperature. The GLC is further extended to investigate whole cells in wet conditions using TEM. We also demonstrate the potential of the GLC for correlative studies by TEM and fluorescence light microscopy imaging. PMID:26065925</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1130240','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1130240"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Aggregative Nanoparticle Growth: Kinetic Modeling of the Size Distribution and Growth Rate</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Woehl, Taylor J.; Park, Chiwoo; Evans, James E.; Arslan, Ilke; Ristenpart, William D.; Browning, Nigel D.</p> <p>2014-01-08</p> <p>ABSTRACT: <span class="hlt">Direct</span> <span class="hlt">observations</span> of solution-phase nanoparticle growth using in situ liquid transmission electron microscopy (TEM) have demonstrated the importance of “non-classical” growth mechanisms, such as aggregation and coalescence, on the growth and final morphology of nanocrystals at the atomic and single nanoparticle scales. To date, groups have quantitatively interpreted the mean growth rate of nanoparticles in terms of the Lifshitz?Slyozov?Wagner (LSW) model for Ostwald ripening, but less attention has been paid to modeling the corresponding particle size distribution. Here we use in situ fluid stage scanning TEM to demonstrate that silver nanoparticles grow by a length-scale dependent mechanism, where individual nanoparticles grow by monomer attachment but ensemble-scale growth is dominated by aggregation. Although our <span class="hlt">observed</span> mean nanoparticle growth rate is consistent with the LSW model, we show that the corresponding particle size distribution is broader and more symmetric than predicted by LSW. Following <span class="hlt">direct</span> <span class="hlt">observations</span> of aggregation, we interpret the ensemble-scale growth using Smoluchowski kinetics and demonstrate that the Smoluchowski model quantitatively captures the mean growth rate and particle size distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3573342','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3573342"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of a highly spin-polarized organic spinterface at room temperature</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Djeghloul, F.; Ibrahim, F.; Cantoni, M.; Bowen, M.; Joly, L.; Boukari, S.; Ohresser, P.; Bertran, F.; Le Fèvre, P.; Thakur, P.; Scheurer, F.; Miyamachi, T.; Mattana, R.; Seneor, P.; Jaafar, A.; Rinaldi, C.; Javaid, S.; Arabski, J.; Kappler, J. -P; Wulfhekel, W.; Brookes, N. B.; Bertacco, R.; Taleb-Ibrahimi, A.; Alouani, M.; Beaurepaire, E.; Weber, W.</p> <p>2013-01-01</p> <p>Organic semiconductors constitute promising candidates toward large-scale electronic circuits that are entirely spintronics-driven. Toward this goal, tunneling magnetoresistance values above 300% at low temperature suggested the presence of highly spin-polarized device interfaces. However, such spinterfaces have not been <span class="hlt">observed</span> <span class="hlt">directly</span>, let alone at room temperature. Thanks to experiments and theory on the model spinterface between phthalocyanine molecules and a Co single crystal surface, we clearly evidence a highly efficient spinterface. Spin-polarised <span class="hlt">direct</span> and inverse photoemission experiments reveal a high degree of spin polarisation at room temperature at this interface. We measured a magnetic moment on the molecule's nitrogen ? orbitals, which substantiates an ab-initio theoretical description of highly spin-polarised charge conduction across the interface due to differing spinterface formation mechanisms in each spin channel. We propose, through this example, a recipe to engineer simple organic-inorganic interfaces with remarkable spintronic properties that can endure well above room temperature. PMID:23412079</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/0908.2124v1','EPRINT'); return false;" href="http://arxiv.org/pdf/0908.2124v1"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of melting in a 2-D superconducting vortex lattice</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>I. Guillamon; H. Suderow; A. Fernandez-Pacheco; J. Sese; R. Cordoba; J. M. De Teresa; M. R. Ibarra; S. Vieira</p> <p>2009-08-14</p> <p>Topological defects such as dislocations and disclinations are predicted to determine the twodimensional (2-D) melting transition. In 2-D superconducting vortex lattices, macroscopic measurements evidence melting close to the transition to the normal state. However, the <span class="hlt">direct</span> <span class="hlt">observation</span> at the scale of individual vortices of the melting sequence has never been performed. Here we provide step by step imaging through scanning tunneling spectroscopy of a 2-D system of vortices up to the melting transition in a focused-ion-beam nanodeposited W-based superconducting thin film. We show <span class="hlt">directly</span> the transition into an isotropic liquid below the superconducting critical temperature. Before that, we find a hexatic phase, characterized by the appearance of free dislocations, and a smectic-like phase, possibly originated through partial disclination unbinding. These results represent a significant step in the understanding of melting of 2-D systems, with impact across several research fields, such as liquid crystal molecules, or lipids in membranes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70025282','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70025282"><span id="translatedtitle"><span class="hlt">Direct</span> assessment of groundwater vulnerability from single <span class="hlt">observations</span> of multiple contaminants</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Worrall, F.; Kolpin, D.W.</p> <p>2003-01-01</p> <p>Groundwater vulnerability is a central concept in pollution risk assessment, yet its estimation has been largely a matter of expert judgment. This work applies a method for the <span class="hlt">direct</span> calculation of vulnerability from monitoring well <span class="hlt">observations</span> of pesticide concentrations. The method has two major advantages: it is independent of the compounds being examined, and it has a <span class="hlt">direct</span> probabilistic interpretation making it ideal for risk assessment. The methodology was applied to data from a groundwater monitoring program in the midwestern United States. The distribution of the vulnerabilities was skewed toward zero. Spatial distribution of the vulnerabilities shows them to be controlled by both regional and local factors. Methods are presented for estimating the necessary sample sizes for vulnerability studies. The further application of the approach developed in this study to understanding groundwater pollution is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.U33B0070H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.U33B0070H"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of ecosystem light use efficiency from MAIAC/MODIS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hall, F. G.; Hilker, T.; Lyapustin, A.; Wang, Y.; Coops, N.; Drolet, G.</p> <p>2009-12-01</p> <p>The fraction of photosynthetically active radiation (FPAR) incident upon and absorbed by vegetated ecosystems is a standard MODIS product. From this and satellite <span class="hlt">observations</span> of incident PAR flux, ecosystem photosynthetic capacity can be measured remotely, but not ecosystem photosynthetic rate. The missing link is remotely sensed <span class="hlt">observations</span> of ecosystem light-use efficiency (LUE) (the efficiency with which ecosystems convert absorbed PAR into carbon), which is modulated by plant physiology in response to rapidly changing extant environmental conditions. LUE is currently estimated from models that attempt to relate plant physiological response to their environment (soil moisture, fertility etc); however accuracies are limited by the uncertainty of the required inputs at landscape scales - primarily precipitation and soil hydrological characteristics. To rectify this situation, a number of recent studies were <span class="hlt">directed</span> at measuring ecosystem LUE <span class="hlt">directly</span> from MODIS using a photochemical reflectance index (PRI) - based on the reflectance measurements from MODIS bands 11 and 12 (~531 and ~550 nm). Results however have shown that quantifying the relationship between MODIS PRI and ecosystem LUE remains challenging. In addition, atmospherically induced aerosol variability confounds the subtle PRI signal. Here, we introduce and evaluate a new approach (MAIAC) that minimizes cloud interference, and aerosol and surface bidirectional reflectance effects on PRI. Using tower measured LUE, we evaluate our approach and demonstrate a strong relationship (r2=0.74, p<0.01) between tower based <span class="hlt">observations</span> of both PRI and LUE and those from atmospherically corrected MODIS data; these correlations remained robust throughout the vegetation period of 2006. Swath <span class="hlt">observations</span> yielded better results than gridded data (r2=0.58, p<0.01) both of which included forward and backscatter <span class="hlt">observations</span>. As expected from theoretical considerations, MODIS PRI values were strongly related to canopy shadow fraction viewed by MODIS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38.1670G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38.1670G"><span id="translatedtitle">Statistical study of muons counts rates in differents <span class="hlt">directions</span>, <span class="hlt">observed</span> at the Brazilian Southern Space Observatory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grams, Guilherme; Schuch, Nelson Jorge; Braga, Carlos Roberto; Purushottam Kane, Rajaram; Echer, Ezequiel; Ronan Coelho Stekel, Tardelli</p> <p></p> <p>Cosmic ray are charged particles, at the most time protons, that reach the earth's magne-tosphere from interplanetary space with velocities greater than the solar wind. When these impinge the atmosphere, they interact with atmosphere constituents and decay into sub-particles forming an atmospheric shower. The muons are the sub-particles which normally maintain the originated <span class="hlt">direction</span> of the primary cosmic ray. A multi-<span class="hlt">directional</span> muon detec-tor (MMD) was installed in 2001 and upgraded in 2005, through an international cooperation between Brazil, Japan and USA, and operated since then at the Southern Space Observatory -SSO/CRS/CCR/INPE -MCT, (29,4° S, 53,8° W, 480m a.s.l.), São Martinho da Serra, RS, a Brazil. The main objetive of this work is to present a statistical analysis of the intensity of muons, with energy between 50 and 170 GeV, in differents <span class="hlt">directions</span>, measured by the SSO's multi-<span class="hlt">directional</span> muon detector. The analysis was performed with data from 2006 and 2007 collected by the SSO's MMD. The MMD consists of two layers of 4x7 detectors with a total <span class="hlt">observation</span> area of 28 m2 . The counting of muons in each <span class="hlt">directional</span> channel is made by a coincidence of pulses pair, one from a detector in the upper layer and the other from a detector in the lower layer. The SSO's MMD is equipped with 119 <span class="hlt">directional</span> channels for muon count rate measurement and is capable of detecting muons incident with zenithal angle between 0° and 75,53° . A statistical analysis was made with the MMD muon count rate for all the <span class="hlt">di-rectional</span> channels. The average and the standard deviation of the muon count rate in each <span class="hlt">directional</span> component were calculated. The results show lower cont rate for the channels with larger zenith, and higher cont rate with smaller zenith, as expected from the production and propagation of muons in the atmosphere. It is also possible to identify the Stormer cone. The SSO's MMD is also a detector component of the Global Muon Detector Network (GMDN), which has been developed in an international collaboration lead by Shinshu University, Japan.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985JGR....90.6829W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985JGR....90.6829W"><span id="translatedtitle">In situ stress estimates from hydraulic fracturing and <span class="hlt">direct</span> <span class="hlt">observation</span> of crack orientation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Warren, William E.; Smith, Carl W.</p> <p>1985-07-01</p> <p>Estimates of in situ stress in G Tunnel, Rainier Mesa, Nevada Test Site, have been obtained with hydraulic fracturing techniques. This work represents a nontraditional use of hydraulic fracturing in that it was performed primarily in horizontal boreholes drilled into the formation from access drifts tunneled into the mesa rather than the usual operation performed at depth in vertical boreholes drilled from the surface. Several operations were performed in essentially orthogonal triads of boreholes located at a point. A significant feature of this work is the mineback operation in which the borehole is mined out to reveal the actual fracture. During the hydraulic fracturing operation, colored dye was added to the fracturing fluid which left an easily detectable stain on the fracture surface. <span class="hlt">Direct</span> <span class="hlt">observation</span> of the fracture orientation away from the borehole establishes the <span class="hlt">direction</span> of the minimum compressive in situ stress and the plane of the other two principal stresses. In one borehole, which was not aligned along a principal stress <span class="hlt">direction</span>, a modified mineback operation revealed a fracture plane that twisted as it grew away from the borehole, aligning itself finally in a plane determined by the in situ stresses. This twisting is consistent with theoretical predictions of borehole stresses under these conditions. This same mineback also showed that fracture of the formation initiated at or under one of the packers, indicating that the packers may have an effet on in situ stress estimates. General <span class="hlt">observations</span> of over 100 tests performed in G Tunnel show that under the sloping portion of the mesa, fracture planes are not vertical but dip in a <span class="hlt">direction</span> tending to parallel the mesa slope. Deep into the tunnel and well under the flat part of the mesa, fractures are essentially vertical with strikes approximately N45°E, which substantiates the usual vertical fracture assumption in traditional fracture operations performed at depth in vertical boreholes. Advantages, limitations, and problem areas associated with extracting in situ stress fields from hydraulic fracture pressure records are discussed in detail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4135331','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4135331"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Coherent Oscillations in Solution due to Microheterogeneous Environment</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Das, Dipak Kumar; Makhal, Krishnandu; Bandyopadhyay, Soumendra Nath; Goswami, Debabrata</p> <p>2014-01-01</p> <p>We report, for the first time, <span class="hlt">direct</span> <span class="hlt">observation</span> of coherent oscillations in the ground-state of IR775 dye due to microheterogeneous environment. Using ultrafast near-infrared degenerate pump-probe technique centered at 800?nm, we present the dynamics of IR775 in a binary mixture of methanol and chloroform at ultra-short time resolution of 30?fs. The dynamics of the dye in binary mixtures, in a time-scale of a few fs to ~740?ps, strongly varies as a function of solvent composition (volume fraction). Multi-oscillation behavior of the coherent vibration was <span class="hlt">observed</span>, which increased with decreasing percentage of methanol in the dye mixture. Maximum number of damped oscillations were <span class="hlt">observed</span> in 20% methanol. The <span class="hlt">observed</span> vibrational wavepacket motion in the ground-state is periodic in nature. We needed two cosine functions to fit the coherent oscillation data as two different solvents were used. Dynamics of the dye molecule in binary mixtures can be explained by wavepacket motion in the ground potential energy surface. More is the confinement of the dye molecule in binary mixtures, more is the number of damped oscillations. The vibrational cooling time, ?2, increases with increase in the confinement of the system. The <span class="hlt">observed</span> wavepacket oscillations in ground-state dynamics continued until 1.6?ps. PMID:25130204</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/990698','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/990698"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observations</span> of Silver Nanoink Sintering and Eutectic Remelt Reaction with Copper</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Elmer, J. W.; Specht, Eliot D</p> <p>2010-01-01</p> <p>Ag nanoink sintering kinetics and subsequent melting is studied using in-situ synchrotron based x-ray diffraction. <span class="hlt">Direct</span> <span class="hlt">observations</span> of Ag nanoink sintering on Cu demonstrate its potential for materials joining since the Ag nanoink sinters at low temperatures but melts at high temperatures. Results show low expansion coefficient of sintered Ag, non-linear expansion as Ag densifies and interdiffuses with Cu above 500 C, remelting consistent with bulk Ag, and eutectic reaction with Cu demonstrating its usefulness as a high temperature bonding medium</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvL.115l7205B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvL.115l7205B"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of a Localized Magnetic Soliton in a Spin-Transfer Nanocontact</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Backes, D.; Macià, F.; Bonetti, S.; Kukreja, R.; Ohldag, H.; Kent, A. D.</p> <p>2015-09-01</p> <p>We report the <span class="hlt">direct</span> <span class="hlt">observation</span> of a localized magnetic soliton in a spin-transfer nanocontact using scanning transmission x-ray microscopy. Experiments are conducted on a lithographically defined 150 nm diameter nanocontact to an ultrathin ferromagnetic multilayer with perpendicular magnetic anisotropy. Element-resolved x-ray magnetic circular dichroism images show an abrupt onset of a magnetic soliton excitation localized beneath the nanocontact at a threshold current. However, the amplitude of the excitation ?2 5 ° at the contact center is far less than that predicted (?18 0 ° ), showing that the spin dynamics is not described by existing models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25526133','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25526133"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of magnetochiral effects through a single metamolecule in microwave regions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tomita, Satoshi; Sawada, Kei; Porokhnyuk, Andrey; Ueda, Tetsuya</p> <p>2014-12-01</p> <p>We report <span class="hlt">direct</span> <span class="hlt">observation</span> of magnetochiral (MCh) effects for the X-band microwaves through a single metamolecule consisting of a copper chiral structure and ferrite rod. A fictitious interaction between chirality and magnetism is realized in the metamolecule without intrinsic electronic interactions. The MCh effects are induced at the resonant optical activities by applying a weak dc magnetic field of 1 mT, and are increased with the magnetic field. The nonreciprocal differences in refractive indices are evaluated to be 10^{-3} at 200 mT. PMID:25526133</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvL.115e5002S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvL.115e5002S"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of the Injection Dynamics of a Laser Wakefield Accelerator Using Few-Femtosecond Shadowgraphy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sävert, A.; Mangles, S. P. D.; Schnell, M.; Siminos, E.; Cole, J. M.; Leier, M.; Reuter, M.; Schwab, M. B.; Möller, M.; Poder, K.; Jäckel, O.; Paulus, G. G.; Spielmann, C.; Skupin, S.; Najmudin, Z.; Kaluza, M. C.</p> <p>2015-07-01</p> <p>We present few-femtosecond shadowgraphic snapshots taken during the nonlinear evolution of the plasma wave in a laser wakefield accelerator with transverse synchronized few-cycle probe pulses. These snapshots can be <span class="hlt">directly</span> associated with the electron density distribution within the plasma wave and give quantitative information about its size and shape. Our results show that self-injection of electrons into the first plasma-wave period is induced by a lengthening of the first plasma period. Three-dimensional particle-in-cell simulations support our <span class="hlt">observations</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26431016','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26431016"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of a Localized Magnetic Soliton in a Spin-Transfer Nanocontact.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Backes, D; Macià, F; Bonetti, S; Kukreja, R; Ohldag, H; Kent, A D</p> <p>2015-09-18</p> <p>We report the <span class="hlt">direct</span> <span class="hlt">observation</span> of a localized magnetic soliton in a spin-transfer nanocontact using scanning transmission x-ray microscopy. Experiments are conducted on a lithographically defined 150 nm diameter nanocontact to an ultrathin ferromagnetic multilayer with perpendicular magnetic anisotropy. Element-resolved x-ray magnetic circular dichroism images show an abrupt onset of a magnetic soliton excitation localized beneath the nanocontact at a threshold current. However, the amplitude of the excitation ?25° at the contact center is far less than that predicted (?180°), showing that the spin dynamics is not described by existing models. PMID:26431016</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ACP.....9.8265B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ACP.....9.8265B"><span id="translatedtitle">Aerosol characterization in Northern Africa, Northeastern Atlantic, Mediterranean Basin and Middle East from <span class="hlt">direct</span>-sun AERONET <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Basart, S.; Pérez, C.; Cuevas, E.; Baldasano, J. M.; Gobbi, G. P.</p> <p>2009-11-01</p> <p>We provide an atmospheric aerosol characterization for North Africa, Northeastern Atlantic, Mediterranean and Middle East based on the analysis of quality-assured <span class="hlt">direct</span>-sun <span class="hlt">observations</span> of 39 stations of the AErosol RObotic NETwork (AERONET) which include at least an annual cycle within the 1994-2007 period. We extensively test and apply the recently introduced graphical method of Gobbi and co-authors to track and discriminate different aerosol types and quantify the contribution of mineral dust. The method relies on the combined analysis of the Ångström exponent (?) and its spectral curvature ??. Plotting data in these coordinates <span class="hlt">allows</span> to infer aerosol fine mode radius (Rf) and fractional contribution (?) to total Aerosol Optical Depth (AOD) and separate AOD growth due to fine-mode aerosol humidification and/or coagulation from AOD growth due to the increase in coarse particles or cloud contamination. Our results confirm the robustness of this graphical method. Large mineral dust is found to be the most important constituent in Northern Africa and Middle East. Under specific meteorological conditions, its transport to Southern Europe is <span class="hlt">observed</span> from spring to autumn and decreasing with latitude. We <span class="hlt">observe</span> "pure Saharan dust" conditions to show AOD>0.7 (ranging up to 5), ?<0.3 and ??<0 corresponding to ?<40% and (Rf)~0.13 ?m. Small pollution particles are abundant in sites close to urban and industrial areas of Continental and Eastern Europe and Middle East, as well as, important contributions of biomass burning are <span class="hlt">observed</span> in the sub-Sahel region in winter. These small aerosols are associated to AOD<1, ?>1.5 and ??~-0.2 corresponding to ?>70% and Rf~0.13 ?m. Here, dust mixed with fine pollution aerosols shifts the <span class="hlt">observations</span> to the region ?<0.75, in which the fine mode contribution is less than 40%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4458887','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4458887"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of TALE protein dynamics reveals a two-state search mechanism</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cuculis, Luke; Abil, Zhanar; Zhao, Huimin; Schroeder, Charles M.</p> <p>2015-01-01</p> <p>Transcription activator-like effector (TALE) proteins are a class of programmable DNA-binding proteins for which the fundamental mechanisms governing the search process are not fully understood. Here we use single-molecule techniques to <span class="hlt">directly</span> <span class="hlt">observe</span> TALE search dynamics along DNA templates. We find that TALE proteins are capable of rapid diffusion along DNA using a combination of sliding and hopping behaviour, which suggests that the TALE search process is governed in part by facilitated diffusion. We also <span class="hlt">observe</span> that TALE proteins exhibit two distinct modes of action during the search process—a search state and a recognition state—facilitated by different subdomains in monomeric TALE proteins. Using TALE truncation mutants, we further demonstrate that the N-terminal region of TALEs is required for the initial non-specific binding and subsequent rapid search along DNA, whereas the central repeat domain is required for transitioning into the site-specific recognition state. PMID:26027871</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1501.02203v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1501.02203v1"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of quark-hadron duality in the free neutron F_2 structure function</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>I. Niculescu; G. Niculescu; W. Melnitchouk; J. Arrington; M. E. Christy; R. Ent; K. A. Griffioen; N. Kalantarians; C. E. Keppel; S. Kuhn; S. Tkachenko; J. Zhang</p> <p>2015-01-09</p> <p>Using data from the recent BONuS experiment at Jefferson Lab, which utilized a novel spectator tagging technique to extract the inclusive electron-free neutron scattering cross section, we obtain the first <span class="hlt">direct</span> <span class="hlt">observation</span> of quark-hadron duality in the neutron F_2 structure function. The data are used to reconstruct the lowest few (N=2, 4 and 6) moments of F_2 in the three prominent nucleon resonance regions, as well as the moments integrated over the entire resonance region. Comparison with moments computed from global parametrizations of parton distribution functions suggest that quark--hadron duality holds locally for the neutron in the second and third resonance regions down to Q^2 ~ 1 GeV^2, with violations possibly up to 20% <span class="hlt">observed</span> in the first resonance region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCo...6E7277C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCo...6E7277C"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of TALE protein dynamics reveals a two-state search mechanism</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cuculis, Luke; Abil, Zhanar; Zhao, Huimin; Schroeder, Charles M.</p> <p>2015-06-01</p> <p>Transcription activator-like effector (TALE) proteins are a class of programmable DNA-binding proteins for which the fundamental mechanisms governing the search process are not fully understood. Here we use single-molecule techniques to <span class="hlt">directly</span> <span class="hlt">observe</span> TALE search dynamics along DNA templates. We find that TALE proteins are capable of rapid diffusion along DNA using a combination of sliding and hopping behaviour, which suggests that the TALE search process is governed in part by facilitated diffusion. We also <span class="hlt">observe</span> that TALE proteins exhibit two distinct modes of action during the search process--a search state and a recognition state--facilitated by different subdomains in monomeric TALE proteins. Using TALE truncation mutants, we further demonstrate that the N-terminal region of TALEs is required for the initial non-specific binding and subsequent rapid search along DNA, whereas the central repeat domain is required for transitioning into the site-specific recognition state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70016962','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70016962"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of frictional contacts: New insights for state-dependent properties</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dieterich, J.H.; Kilgore, B.D.</p> <p>1994-01-01</p> <p>Rocks and many other materials display a rather complicated, but characteristic, dependence of friction on sliding history. These effects are well-described by empirical rate- and state-dependent constitutive formulations which have been utilized for analysis of fault slip and earthquake processes. We present a procedure for <span class="hlt">direct</span> quantitative microscopic <span class="hlt">observation</span> of frictional contacts during slip. The <span class="hlt">observations</span> reveal that frictional state dependence represents an increase of contact area with contact age. Transient changes of sliding resistance correlate with changes in contact area and arise from shifts of contact population age. Displacement-dependent replacement of contact populations is shown to cause the diagnostic evolution of friction over a characteristic sliding distance that occurs whenever slip begins or sliding conditions change. ?? 1994 Birkha??user Verlag.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4411290','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4411290"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of liquid nucleus growth in homogeneous melting of colloidal crystals</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wang, Ziren; Wang, Feng; Peng, Yi; Han, Yilong</p> <p>2015-01-01</p> <p>The growth behaviour of liquid nucleus is crucial for crystal melting, but its kinetics is difficult to predict and remains challenging in experiment. Here we <span class="hlt">directly</span> <span class="hlt">observed</span> the growth of individual liquid nuclei in homogeneous melting of three-dimensional superheated colloidal crystals with single-particle dynamics by video microscopy. The growth rate of nucleus at weak superheating is well fitted by generalizing the Wilson–Frenkel law of crystallization to melting and including the surface tension effects and non-spherical-shape effects. As the degree of superheating increases, the growth rate is enhanced by nucleus shape fluctuation, nuclei coalescence and multimer attachment. The results provide new guidance for the refinement of nucleation theory, especially for the poorly understood strong-superheating regime. The universal Lindemann parameter <span class="hlt">observed</span> at the superheat limit and solid–liquid interfaces indicates a connection between homogeneous and heterogeneous melting. PMID:25897801</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26645468','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26645468"><span id="translatedtitle">Interactions between C and Cu atoms in single-layer graphene: <span class="hlt">direct</span> <span class="hlt">observation</span> and modelling.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kano, Emi; Hashimoto, Ayako; Kaneko, Tomoaki; Tajima, Nobuo; Ohno, Takahisa; Takeguchi, Masaki</p> <p>2015-12-17</p> <p>Metal doping into the graphene lattice has been studied recently to develop novel nanoelectronic devices and to gain an understanding of the catalytic activities of metals in nanocarbon structures. Here we report the <span class="hlt">direct</span> <span class="hlt">observation</span> of interactions between Cu atoms and single-layer graphene by transmission electron microscopy. We document stable configurations of Cu atoms in the graphene sheet and unique transformations of graphene promoted by Cu atoms. First-principles calculations based on density functional theory reveal a reduction of energy barrier that caused rotation of C-C bonds near Cu atoms. We discuss two driving forces, electron irradiation and in situ heating, and conclude that the <span class="hlt">observed</span> transformations were mainly promoted by electron irradiation. Our results suggest that individual Cu atoms can promote reconstruction of single-layer graphene. PMID:26645468</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCo...6E6942W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCo...6E6942W"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of liquid nucleus growth in homogeneous melting of colloidal crystals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Ziren; Wang, Feng; Peng, Yi; Han, Yilong</p> <p>2015-04-01</p> <p>The growth behaviour of liquid nucleus is crucial for crystal melting, but its kinetics is difficult to predict and remains challenging in experiment. Here we <span class="hlt">directly</span> <span class="hlt">observed</span> the growth of individual liquid nuclei in homogeneous melting of three-dimensional superheated colloidal crystals with single-particle dynamics by video microscopy. The growth rate of nucleus at weak superheating is well fitted by generalizing the Wilson-Frenkel law of crystallization to melting and including the surface tension effects and non-spherical-shape effects. As the degree of superheating increases, the growth rate is enhanced by nucleus shape fluctuation, nuclei coalescence and multimer attachment. The results provide new guidance for the refinement of nucleation theory, especially for the poorly understood strong-superheating regime. The universal Lindemann parameter <span class="hlt">observed</span> at the superheat limit and solid-liquid interfaces indicates a connection between homogeneous and heterogeneous melting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCo...6E8889B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCo...6E8889B"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> and imaging of a spin-wave soliton with p-like symmetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bonetti, S.; Kukreja, R.; Chen, Z.; Macià, F.; Hernàndez, J. M.; Eklund, A.; Backes, D.; Frisch, J.; Katine, J.; Malm, G.; Urazhdin, S.; Kent, A. D.; Stöhr, J.; Ohldag, H.; Dürr, H. A.</p> <p>2015-11-01</p> <p>Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no <span class="hlt">direct</span> experimental <span class="hlt">observation</span> exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50 ps temporal resolution and 35 nm spatial resolution, we are able to create a real-space spin-wave movie and <span class="hlt">observe</span> the emergence of a localized soliton with a nodal line, that is, with p-like symmetry. Micromagnetic simulations explain the measurements and reveal that the symmetry of the soliton can be controlled by magnetic fields. Our results broaden the understanding of spin-wave dynamics at the nanoscale, with implications for the design of magnetic nanodevices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26567699','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26567699"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> and imaging of a spin-wave soliton with p-like symmetry.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bonetti, S; Kukreja, R; Chen, Z; Macià, F; Hernàndez, J M; Eklund, A; Backes, D; Frisch, J; Katine, J; Malm, G; Urazhdin, S; Kent, A D; Stöhr, J; Ohldag, H; Dürr, H A</p> <p>2015-01-01</p> <p>Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no <span class="hlt">direct</span> experimental <span class="hlt">observation</span> exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50?ps temporal resolution and 35?nm spatial resolution, we are able to create a real-space spin-wave movie and <span class="hlt">observe</span> the emergence of a localized soliton with a nodal line, that is, with p-like symmetry. Micromagnetic simulations explain the measurements and reveal that the symmetry of the soliton can be controlled by magnetic fields. Our results broaden the understanding of spin-wave dynamics at the nanoscale, with implications for the design of magnetic nanodevices. PMID:26567699</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4660209','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4660209"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> and imaging of a spin-wave soliton with p-like symmetry</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bonetti, S.; Kukreja, R.; Chen, Z.; Macià, F.; Hernàndez, J. M.; Eklund, A.; Backes, D.; Frisch, J.; Katine, J.; Malm, G.; Urazhdin, S.; Kent, A. D.; Stöhr, J.; Ohldag, H.; Dürr, H. A.</p> <p>2015-01-01</p> <p>Spin waves, the collective excitations of spins, can emerge as nonlinear solitons at the nanoscale when excited by an electrical current from a nanocontact. These solitons are expected to have essentially cylindrical symmetry (that is, s-like), but no <span class="hlt">direct</span> experimental <span class="hlt">observation</span> exists to confirm this picture. Using a high-sensitivity time-resolved magnetic X-ray microscopy with 50?ps temporal resolution and 35?nm spatial resolution, we are able to create a real-space spin-wave movie and <span class="hlt">observe</span> the emergence of a localized soliton with a nodal line, that is, with p-like symmetry. Micromagnetic simulations explain the measurements and reveal that the symmetry of the soliton can be controlled by magnetic fields. Our results broaden the understanding of spin-wave dynamics at the nanoscale, with implications for the design of magnetic nanodevices. PMID:26567699</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12827091','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12827091"><span id="translatedtitle"><span class="hlt">Directly</span> <span class="hlt">observed</span> therapy (DOT) for individuals with HIV: successes and challenges.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mitty, Jennifer Adelson; Macalino, Grace; Taylor, Lynn; Harwell, Joseph I; Flanigan, Timothy P</p> <p>2003-02-01</p> <p>Many HIV-infected individuals have not reaped the benefits of combination antiretroviral therapy due to inability either to adhere to medications or to access care. It is now recognized that innovative approaches are needed to increase access and adherence to highly active antiretroviral therapy (HAART), especially among these hard-to-reach populations. Due to the success of <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (DOT) for the treatment of Mycobacterium tuberculosis (TB), our group and others have questioned whether DOT can be adapted to deliver HAART to hard-to-reach communities. In this review, we discuss the results of pilot programs that have utilized DOT in multiple different settings and use case studies to explore the diverse issues that can arise when implementing these programs. As we continue to gain more experience with <span class="hlt">observed</span> therapy, we will be able to better identify the key components for a successful intervention. PMID:12827091</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25192212','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25192212"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of phonon emission from hot electrons: spectral features in diamond secondary electron emission.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>O'Donnell, Kane M; Edmonds, Mark T; Ristein, Jürgen; Rietwyk, Kevin J; Tadich, Anton; Thomsen, Lars; Pakes, Christopher I; Ley, Lothar</p> <p>2014-10-01</p> <p>In this work we use high-resolution synchrotron-based photoelectron spectroscopy to investigate the low kinetic energy electron emission from two negative electron affinity surfaces of diamond, namely hydrogenated and lithiated diamond. For hydrogen-terminated diamond electron emission below the conduction band minimum (CBM) is clearly <span class="hlt">observed</span> as a result of phonon emission subsequent to carrier thermalization at the CBM. In the case of lithiated diamond, we find the normal conduction band minimum emission peak is asymmetrically broadened to higher kinetic energies and argue the broadening is a result of ballistic emission from carriers thermalized to the CBM in the bulk well before the onset of band-bending. In both cases the spectra display intensity modulations that are the signature of optical phonon emission as the main mechanism for carrier relaxation. To our knowledge, these measurements represent the first <span class="hlt">direct</span> <span class="hlt">observation</span> of hot carrier energy loss via photoemission. PMID:25192212</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Sci...348.1455K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Sci...348.1455K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of an abrupt insulator-to-metal transition in dense liquid deuterium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knudson, M. D.; Desjarlais, M. P.; Becker, A.; Lemke, R. W.; Cochrane, K. R.; Savage, M. E.; Bliss, D. E.; Mattsson, T. R.; Redmer, R.</p> <p>2015-06-01</p> <p>Eighty years ago, it was proposed that solid hydrogen would become metallic at sufficiently high density. Despite numerous investigations, this transition has not yet been experimentally <span class="hlt">observed</span>. More recently, there has been much interest in the analog of this predicted metallic transition in the dense liquid, due to its relevance to planetary science. Here, we show <span class="hlt">direct</span> <span class="hlt">observation</span> of an abrupt insulator-to-metal transition in dense liquid deuterium. Experimental determination of the location of this transition provides a much-needed benchmark for theory and may constrain the region of hydrogen-helium immiscibility and the boundary-layer pressure in standard models of the internal structure of gas-giant planets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3645455','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3645455"><span id="translatedtitle">A multimethod investigation including <span class="hlt">direct</span> <span class="hlt">observation</span> of 3751 patient visits to 120 dental offices</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wotman, Stephen; Demko, Catherine A; Victoroff, Kristin; Sudano, Joseph J; Lalumandier, James A</p> <p>2010-01-01</p> <p>This report defines verbal interactions between practitioners and patients as core activities of dental practice. Trained teams spent four days in 120 Ohio dental practices <span class="hlt">observing</span> 3751 patient encounters with dentists and hygienists. <span class="hlt">Direct</span> <span class="hlt">observation</span> of practice characteristics, procedures performed, and how procedure and nonprocedure time was utilized during patient visits was recorded using a modified Davis <span class="hlt">Observation</span> Code that classified patient contact time into 24 behavioral categories. Dentist, hygienist, and patient characteristics were gathered by questionnaire. The most common nonprocedure behaviors <span class="hlt">observed</span> for dentists were chatting, evaluation feedback, history taking, and answering patient questions. Hygienists added preventive counseling. We distinguish between preventive procedures and counseling in actual dental offices that are members of a practice-based research network. Almost a third of the dentist’s and half of the hygienist’s patient contact time is utilized for nonprocedure behaviors during patient encounters. These interactions may be linked to patient and practitioner satisfaction and effectiveness of self-care instruction. PMID:23662080</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26123380','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26123380"><span id="translatedtitle">Cortical kinematic processing of executed and <span class="hlt">observed</span> goal-<span class="hlt">directed</span> hand actions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marty, Brice; Bourguignon, Mathieu; Jousmäki, Veikko; Wens, Vincent; Op de Beeck, Marc; Van Bogaert, Patrick; Goldman, Serge; Hari, Riitta; De Tiège, Xavier</p> <p>2015-10-01</p> <p>Motor information conveyed by viewing the kinematics of an agent's action helps to predict how the action will unfold. Still, how <span class="hlt">observed</span> movement kinematics is processed in the brain remains to be clarified. Here, we used magnetoencephalography (MEG) to determine at which frequency and where in the brain, the neural activity is coupled with the kinematics of executed and <span class="hlt">observed</span> motor actions. Whole-scalp MEG signals were recorded from 11 right-handed healthy adults while they were executing (Self) or <span class="hlt">observing</span> (Other) similar goal-<span class="hlt">directed</span> hand actions performed by an actor placed in front of them. Actions consisted of pinching with the right hand green foam-made pieces mixed in a heap with pieces of other colors placed on a table, and put them in a plastic pot on the right side of the heap. Subjects' and actor's forefinger movements were monitored with an accelerometer. The coherence between movement acceleration and MEG signals was computed at the sensor level. Then, cortical sources coherent with movement acceleration were identified with Dynamic Imaging of Coherent Sources. Statistically significant sensor-level coherence peaked at the movement frequency (F0) and its first harmonic (F1) in both movement conditions. Apart from visual cortices, statistically significant local maxima of coherence were <span class="hlt">observed</span> in the right posterior superior temporal gyrus (F0), bilateral superior parietal lobule (F0 or F1) and primary sensorimotor cortex (F0 or F1) in both movement conditions. These results suggest that <span class="hlt">observing</span> others' actions engages the viewer's brain in a similar kinematic-related manner as during own action execution. These findings bring new insights into how human brain activity covaries with essential features of <span class="hlt">observed</span> movements of others. PMID:26123380</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16823447','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16823447"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the superfluid phase transition in ultracold Fermi gases.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zwierlein, Martin W; Schunck, Christian H; Schirotzek, André; Ketterle, Wolfgang</p> <p>2006-07-01</p> <p>Phase transitions are dramatic phenomena: water freezes into ice, atomic spins spontaneously align in a magnet, and liquid helium becomes superfluid. Sometimes, such a drastic change in behaviour is accompanied by a visible change in appearance. The hallmark of Bose-Einstein condensation and superfluidity in trapped, weakly interacting Bose gases is the sudden formation of a dense central core inside a thermal cloud. However, in strongly interacting gases--such as the recently <span class="hlt">observed</span> fermionic superfluids--there is no longer a clear separation between the superfluid and the normal parts of the cloud. The detection of fermion pair condensates has required magnetic field sweeps into the weakly interacting regime, and the quantitative description of these sweeps presents a major theoretical challenge. Here we report the <span class="hlt">direct</span> <span class="hlt">observation</span> of the superfluid phase transition in a strongly interacting gas of 6Li fermions, through sudden changes in the shape of the clouds--in complete analogy to the case of weakly interacting Bose gases. By preparing unequal mixtures of the two spin components involved in the pairing, we greatly enhance the contrast between the superfluid core and the normal component. Furthermore, the distribution of non-interacting excess atoms serves as a <span class="hlt">direct</span> and reliable thermometer. Even in the normal state, strong interactions significantly deform the density profile of the majority spin component. We show that it is these interactions that drive the normal-to-superfluid transition at the critical population imbalance of 70 +/- 5 per cent (ref. 12). PMID:16823447</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130012639','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130012639"><span id="translatedtitle">The Exozodiacal Dust Problem for <span class="hlt">Direct</span> <span class="hlt">Observations</span> of ExoEarths</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Roberge, Aki; Chen, Christine H.; Millan-Gabet, Rafael; Weinberger, Alycia J.; Hinz, Philip M.; Stapelfeldt, Karl R.; Absil, Olivier; Kuchner, Marc J.; Bryden, Geoffrey</p> <p>2012-01-01</p> <p>Debris dust in the habitable zones of stars otherwise known as exozodiacal dust comes from extrasolar asteroids and comets and is thus an expected part of a planetary system. Background flux from the Solar Systems zodiacal dust and the exozodiacal dust in the target system is likely to be the largest source of astrophysical noise in <span class="hlt">direct</span> <span class="hlt">observations</span> of terrestrial planets in the habitable zones of nearby stars. Furthermore, dust structures like clumps, thought to be produced by dynamical interactions with exoplanets, are a possible source of confusion. In this paper, we qualitatively assess the primary impact of exozodical dust on high-contrast <span class="hlt">direct</span> imaging at optical wavelengths, such as would be performed with a coronagraph. Then we present the sensitivity of previous, current, and near-term facilities to thermal emission from debris dust at all distances from nearby solar-type stars, as well as our current knowledge of dust levels from recent surveys. Finally, we address the other method of detecting debris dust, through high-contrast imaging in scattered light. This method is currently far less sensitive than thermal emission <span class="hlt">observations</span>, but provides high spatial resolution for studying dust structures. This paper represents the first report of NASA's Exoplanet Exploration Program Analysis Group (ExoPAG).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4682087','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4682087"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Photoinduced Charge Separation in Ruthenium Complex/Ni(OH)2 Nanoparticle Hybrid</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tang, Yu; Pattengale, Brian; Ludwig, John; Atifi, Abderrahman; Zinovev, Alexander V.; Dong, Bin; Kong, Qingyu; Zuo, Xiaobing; Zhang, Xiaoyi; Huang, Jier</p> <p>2015-01-01</p> <p>Ni(OH)2 have emerged as important functional materials for solar fuel conversion because of their potential as cost-effective bifunctional catalysts for both hydrogen and oxygen evolution reactions. However, their roles as photocatalysts in the photoinduced charge separation (CS) reactions remain unexplored. In this paper, we investigate the CS dynamics of a newly designed hybrid catalyst by integrating a Ru complex with Ni(OH)2 nanoparticles (NPs). Using time resolved X-ray absorption spectroscopy (XTA), we <span class="hlt">directly</span> <span class="hlt">observed</span> the formation of the reduced Ni metal site (~60?ps), unambiguously demonstrating CS process in the hybrid through ultrafast electron transfer from Ru complex to Ni(OH)2 NPs. Compared to the ultrafast CS process, the charge recombination in the hybrid is ultraslow (?50?ns). These results not only suggest the possibility of developing Ni(OH)2 as solar fuel catalysts, but also represent the first time <span class="hlt">direct</span> <span class="hlt">observation</span> of efficient CS in a hybrid catalyst using XTA. PMID:26673578</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26673578','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26673578"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Photoinduced Charge Separation in Ruthenium Complex/Ni(OH)2 Nanoparticle Hybrid.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tang, Yu; Pattengale, Brian; Ludwig, John; Atifi, Abderrahman; Zinovev, Alexander V; Dong, Bin; Kong, Qingyu; Zuo, Xiaobing; Zhang, Xiaoyi; Huang, Jier</p> <p>2015-01-01</p> <p>Ni(OH)2 have emerged as important functional materials for solar fuel conversion because of their potential as cost-effective bifunctional catalysts for both hydrogen and oxygen evolution reactions. However, their roles as photocatalysts in the photoinduced charge separation (CS) reactions remain unexplored. In this paper, we investigate the CS dynamics of a newly designed hybrid catalyst by integrating a Ru complex with Ni(OH)2 nanoparticles (NPs). Using time resolved X-ray absorption spectroscopy (XTA), we <span class="hlt">directly</span> <span class="hlt">observed</span> the formation of the reduced Ni metal site (~60?ps), unambiguously demonstrating CS process in the hybrid through ultrafast electron transfer from Ru complex to Ni(OH)2 NPs. Compared to the ultrafast CS process, the charge recombination in the hybrid is ultraslow (?50?ns). These results not only suggest the possibility of developing Ni(OH)2 as solar fuel catalysts, but also represent the first time <span class="hlt">direct</span> <span class="hlt">observation</span> of efficient CS in a hybrid catalyst using XTA. PMID:26673578</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4156133','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4156133"><span id="translatedtitle">13C? decoupling during <span class="hlt">direct</span> <span class="hlt">observation</span> of carbonyl resonances in solution NMR of isotopically enriched proteins</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ying, Jinfa; Li, Fang; Lee, Jung Ho; Bax, Ad</p> <p>2014-01-01</p> <p><span class="hlt">Direct</span> detection of 13C can be advantageous when studying uniformly enriched proteins, in particular for paramagnetic proteins or when hydrogen exchange with solvent is fast. A scheme recently introduced for long-<span class="hlt">observation</span>-window band-selective homonuclear decoupling in solid state NMR, LOW-BASHD (Struppe et al., J. Magn. Reson. 236, 89–94, 2013) is shown to be effective for 13C? decoupling during <span class="hlt">direct</span> 13C? <span class="hlt">observation</span> in solution NMR experiments too. For this purpose, adjustment of the decoupling pulse parameters and delays is demonstrated to be important for increasing spectral resolution, to reduce three-spin effects, and to decrease the intensity of decoupling side-bands. LOW-BASHD then yields 13C? line widths comparable to those obtained with the popular IPAP method, while enhancing sensitivity by ca 35%. As a practical application of LOW-BASHD decoupling, requiring quantitative intensity measurement over a wide dynamic range, the impact of lipid binding on the 13C?-detected NCO spectrum of the intrinsically disordered protein ?-synuclein is compared with that on the 1H-detected 1H-15N HSQC spectrum. Results confirm that synuclein’s “dark state” behavior is not caused by paramagnetic relaxation or rapid hydrogen exchange. PMID:25129622</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PrSS...90..239K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PrSS...90..239K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> and control of hydrogen-bond dynamics using low-temperature scanning tunneling microscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kumagai, Takashi</p> <p>2015-08-01</p> <p>Hydrogen(H)-bond dynamics are involved in many elementary processes in chemistry and biology. Because of its fundamental importance, a variety of experimental and theoretical approaches have been employed to study the dynamics in gas, liquid, solid phases, and their interfaces. This review describes the recent progress of <span class="hlt">direct</span> <span class="hlt">observation</span> and control of H-bond dynamics in several model systems on a metal surface by using low-temperature scanning tunneling microscopy (STM). General aspects of H-bond dynamics and the experimental methods are briefly described in chapter 1 and 2. In the subsequent four chapters, I present <span class="hlt">direct</span> <span class="hlt">observation</span> of an H-bond exchange reaction within a single water dimer (chapter 3), a symmetric H bond (chapter 4) and H-atom relay reactions (chapter 5) within water-hydroxyl complexes, and an intramolecular H-atom transfer reaction (tautomerization) within a single porphycene molecule (chapter 6). These results provide novel microscopic insights into H-bond dynamics at the single-molecule level, and highlight significant impact on the process from quantum effects, namely tunneling and zero-point vibration, resulting from the small mass of H atom. Additionally, local environmental effect on H-bond dynamics is also examined by using atom/molecule manipulation with the STM.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ842837.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ842837.pdf"><span id="translatedtitle">Video <span class="hlt">Allows</span> Young Scientists New Ways to Be Seen</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Park, John C.</p> <p>2009-01-01</p> <p>Science is frequently a visual endeavor, dependent on <span class="hlt">direct</span> or indirect <span class="hlt">observations</span>. Teachers have long employed motion pictures in the science classroom to <span class="hlt">allow</span> students to make indirect <span class="hlt">observations</span>, but the capabilities of digital video offer opportunities to engage students in active science learning. Not only can watching a digital video…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSH53B4214S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSH53B4214S"><span id="translatedtitle">Toward the <span class="hlt">Direct</span> Measurement of Coronal Magnetic Fields: An Airborne Infrared Spectrometer for Eclipse <span class="hlt">Observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Samra, J.; DeLuca, E. E.; Golub, L.; Cheimets, P.</p> <p>2014-12-01</p> <p>The solar magnetic field enables the heating of the corona and provides its underlying structure. Energy stored in coronal magnetic fields is released in flares and coronal mass ejections (CME) and provides the ultimate source of energy for space weather. Therefore, <span class="hlt">direct</span> measurements of the coronal magnetic field have significant potential to enhance understanding of coronal dynamics and improve solar forecasting models. Of particular interest are <span class="hlt">observations</span> of coronal field lines in the transitional region between closed and open flux systems, providing important information on the origin of the slow solar wind. While current instruments routinely <span class="hlt">observe</span> only the photospheric and chromospheric magnetic fields, a proposed airborne spectrometer will take a step toward the <span class="hlt">direct</span> <span class="hlt">observation</span> of coronal fields by measuring plasma emission in the infrared at high spatial and spectral resolution. The targeted lines are four forbidden magnetic dipole transitions between 2 and 4 ?m. The airborne system will consist of a telescope, grating spectrometer, and pointing/stabilization system to be flown on the NSF/NCAR High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) during the August 2017 total solar eclipse. The project incorporates several optical engineering challenges, centered around maintaining adequate spectral and spatial resolution in a compact and inexpensive package and on a moving platform. Design studies are currently underway to examine the tradeoffs between various optical geometries and control strategies for the pointing/stabilization system. The results will be presented and interpreted in terms of the consequences for the scientific questions. In addition, results from a laboratory prototype and simulations of the final system will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1710164M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1710164M"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of a mini-magnetosphere in the lunar plasma wake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Yonghui; Wong, Hon-Cheng; Xu, Xiaojun</p> <p>2015-04-01</p> <p>In this report, we present <span class="hlt">direct</span> <span class="hlt">observations</span> of a mini-magnetosphere when ARTEMIS P2 is passing through the lunar wake, where the lunar surface and crustal fields are shielded from the solar wind flows. We find the magnetic field amplification simultaneously with the dropout of plasma density and particle energy fluxes when the orbit of P2 is just over the margin of Imbrium antipode anomaly which is centered at 162o E, 33o S. The <span class="hlt">observational</span> interval of these characteristic features is merely 95 seconds (from 1413:15 UT to 1414:50 UT on December 9th 2012) and the orbit altitude of P2 is ~226 km. The strength of magnetic field at P2 orbit altitude (~226 km) can reach ~9 nT over the anomaly region compared to the relatively small value of ~6 nT in the neighboring regions. In addition to these, we also detect the moderate ion and electron temperature increase inside the mini-magnetosphere as well as the rotation in the magnetic field <span class="hlt">direction</span> near the boundary of mini-magnetosphere. These field and plasma parameters demonstrate that the vertical size of the mini-magnetosphere near lunar surface can at least extend to ~230 km in the near-vacuum lunar wake without the interaction with the solar wind. We also try to explain the detailed plasma dynamics performed within this mini-magnetosphere by dipole model or non-dipolar model. This study may open up a new view of studying lunar mini-magnetosphere by spacecraft <span class="hlt">observations</span> in the lunar wake where magnetic anomaly fields are almost undisturbed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeCoA.109..113K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeCoA.109..113K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of the influence of solution composition on magnesite dissolution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>King, Helen E.; Putnis, Christine V.</p> <p>2013-05-01</p> <p>In situ <span class="hlt">observations</span> during atomic force microscopy experiments and ex situ <span class="hlt">observations</span> after static and flow-through experiments were used to explore the effect of three different electrolytes on magnesite (MgCO3) dissolution at pH 2. The experiments showed that the magnesite dissolution rate varied in the order NO3->Cl>SO42- when these anions were present in solution. Under the experimental conditions magnesite dissolution occurred via the removal of successive single surface layers, where changes in magnesite reactivity in the presence of different electrolytes could be <span class="hlt">observed</span> as variations in the cycle length for the removal of one unit cell layer. The cycles began with the formation of sporadically distributed etch pits followed by the nucleation of homogeneously distributed etch pits. Coalescence of the etch pits formed isolated sections of the remnant surface, which then dissolved away. The timing of sporadic and homogeneous etch pit nucleation was constant despite the presence of different anions. However, the cycles in surface roughness and etch pit spreading rates indicate that the different anions affect step retreat rates and hence dissolution rates. Differences in magnesite reactivity can be attributed to the <span class="hlt">direct</span> interaction of sulphate with the magnesite surface and the indirect effects of chloride and nitrate on the magnesite surface hydration and hydration of the Mg2+ ion in solution. In all experiments during the dissolution process evidence for the precipitation of a new phase was <span class="hlt">observed</span>, either <span class="hlt">directly</span> as precipitates forming on the magnesite surface in the AFM and after the experiments, seen in SEM analysis, or as changes in the Mg outlet concentration during flow-through experiments. EDX and Raman spectroscopy were used to analyse the composition of the precipitate and although it could not be definitively identified, considering previous <span class="hlt">observations</span> the precipitate is most likely a hydrated Mg-carbonate phase with a MgCO3·xH2O composition. Thus, the formation of a precipitate can facilitate further magnesite dissolution by increasing the undersaturation of the interfacial solution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2527876','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2527876"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of reaction intermediates for a well defined heterogeneous alkene metathesis catalyst</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Blanc, Frédéric; Berthoud, Romain; Copéret, Christophe; Lesage, Anne; Emsley, Lyndon; Singh, Rojendra; Kreickmann, Thorsten; Schrock, Richard R.</p> <p>2008-01-01</p> <p>Grafting of [W(?NAr)(=CHtBu)(2,5-Me2NC4H2)2] on a silica partially dehydroxylated at 700°C (SiO2- (700)) generates the corresponding monosiloxy complex [(?SiO)W(?NAr)(=CHtBu)(2,5-Me2NC4H2)] as the major species (?90%) along with [(?SiO)W(?NAr)(CH2tBu)(2,5-Me2NC4H2)2], according to mass balance analysis, IR, and NMR studies. This heterogeneous catalyst displays good activity and stability in the metathesis of propene. Very importantly, solid state NMR spectroscopy <span class="hlt">allows</span> <span class="hlt">observation</span> of the propagating alkylidene as well as stable metallacyclobutane intermediates. These species have the same reactivity as the initial surface complex [(?SiO)W(?NAr)(=CHtBu)(2,5-Me2NC4H2)], which shows that they are the key intermediates of alkene metathesis. PMID:18723685</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25705986','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25705986"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of nanometer-scale pores of melittin in supported lipid monolayers.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Giménez, Diana; Sánchez-Muñoz, Orlando L; Salgado, Jesús</p> <p>2015-03-17</p> <p>Melittin is the most studied membrane-active peptide and archetype within a large and diverse group of pore formers. However, the molecular characteristics of melittin pores remain largely unknown. Herein, we show by atomic force microscopy (AFM) that lipid monolayers in the presence of melittin are decorated with numerous regularly shaped circular pores that can be distinguished from nonspecific monolayer defects. The specificity of these pores is reinforced through a statistical evaluation of depressions found in Langmuir-Blodgett monolayers in the presence and absence of melittin, which eventually <span class="hlt">allows</span> characterization of the melittin-induced pores at a quantitative low-resolution level. We <span class="hlt">observed</span> that the large majority of pores exhibit near-circular symmetry and a Gaussian distribution in size, with a mean diameter of ?8.7 nm. A distinctive feature is a ring of material found around the pores, made by, on average, three positive peaks, with a height over the level of the lipidic background of ?0.23 nm. This protruding rim is most likely due to the presence of melittin near the pore border. Although the current resolution of the AFM images in the {x, y} plane does not <span class="hlt">allow</span> distinction of the specific organization of the peptide molecules, these results provide an unprecedented view of melittin pores formed in lipidic interfaces and open new perspectives for future structural investigations of these and other pore-forming peptides and proteins using supported monolayers. PMID:25705986</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvE..91c1104F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvE..91c1104F"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the two-plasmon-decay common plasma wave using ultraviolet Thomson scattering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Follett, R. K.; Edgell, D. H.; Henchen, R. J.; Hu, S. X.; Katz, J.; Michel, D. T.; Myatt, J. F.; Shaw, J.; Froula, D. H.</p> <p>2015-03-01</p> <p>A 263-nm Thomson-scattering beam was used to <span class="hlt">directly</span> probe two-plasmon-decay (TPD) excited electron plasma waves (EPWs) driven by between two and five 351-nm beams on the OMEGA Laser System. The amplitude of these waves was nearly independent of the number of drive beams at constant overlapped intensity, showing that the <span class="hlt">observed</span> EPWs are common to the multiple beams. In an experimental configuration where the Thomson-scattering diagnostic was not wave matched to the common TPD EPWs, a broad spectrum of TPD-driven EPWs was <span class="hlt">observed</span>, indicative of nonlinear effects associated with TPD saturation. Electron plasma waves corresponding to Langmuir decay of TPD EPWs were <span class="hlt">observed</span> in both Thomson-scattering spectra, suggesting the Langmuir decay instability as a TPD saturation mechanism. Simulated Thomson-scattering spectra from three-dimensional numerical solutions of the extended Zakharov equations of TPD are in excellent agreement with the experimental spectra and verify the presence of the Langmuir decay instability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25871046','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25871046"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the two-plasmon-decay common plasma wave using ultraviolet Thomson scattering.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Follett, R K; Edgell, D H; Henchen, R J; Hu, S X; Katz, J; Michel, D T; Myatt, J F; Shaw, J; Froula, D H</p> <p>2015-03-01</p> <p>A 263-nm Thomson-scattering beam was used to <span class="hlt">directly</span> probe two-plasmon-decay (TPD) excited electron plasma waves (EPWs) driven by between two and five 351-nm beams on the OMEGA Laser System. The amplitude of these waves was nearly independent of the number of drive beams at constant overlapped intensity, showing that the <span class="hlt">observed</span> EPWs are common to the multiple beams. In an experimental configuration where the Thomson-scattering diagnostic was not wave matched to the common TPD EPWs, a broad spectrum of TPD-driven EPWs was <span class="hlt">observed</span>, indicative of nonlinear effects associated with TPD saturation. Electron plasma waves corresponding to Langmuir decay of TPD EPWs were <span class="hlt">observed</span> in both Thomson-scattering spectra, suggesting the Langmuir decay instability as a TPD saturation mechanism. Simulated Thomson-scattering spectra from three-dimensional numerical solutions of the extended Zakharov equations of TPD are in excellent agreement with the experimental spectra and verify the presence of the Langmuir decay instability. PMID:25871046</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MMTA...46.5058S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MMTA...46.5058S"><span id="translatedtitle">Deformation Twinning in Zirconium: <span class="hlt">Direct</span> Experimental <span class="hlt">Observations</span> and Polycrystal Plasticity Predictions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, Jaiveer; Mahesh, Sivasambu; Kumar, Gulshan; Pant, Prita; Srivastava, D.; Dey, G. K.; Saibaba, N.; Samajdar, I.</p> <p>2015-11-01</p> <p>Deformation twinning was <span class="hlt">directly</span> <span class="hlt">observed</span> in three commercial zirconium alloy samples during split channel die plane-strain compression. One pair of samples had similar starting texture but different grain size distributions, while another pair had similar grain size distribution but different starting textures. Extension twinning was found to be more sensitive to the starting texture than to the grain size distribution. Also, regions of intense deformation near grain boundaries were <span class="hlt">observed</span>. A hierarchical binary tree-based polycrystal plasticity model, implementing the Chin-Hosford-Mendorf twinning criterion, captured the experimentally <span class="hlt">observed</span> twinning grains' lattice orientation distribution, and the twin volume fraction evolution, provided the critical resolved shear stress for extension twinning, ?0 , was assumed much larger than any of the values reported in the literature, based on the viscoplastic self-consistent model. A comparison of the models suggests that ?0 obtained using the present model and the viscoplastic self-consistent models physically correspond to the critical stress required for twin nucleation, and twin growth, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JLTP..175..385B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JLTP..175..385B"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of a Majorana Quasiparticle Heat Capacity in 3He</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bunkov, Y. M.</p> <p>2014-04-01</p> <p>The Majorana fermion, which acts as its own antiparticle, was suggested by Majorana in 1937 (Nuovo Cimento 14:171). While no stable particle with Majorana properties has yet been <span class="hlt">observed</span>, Majorana quasiparticles (QP) may exist at the boundaries of topological insulators. Here we report the preliminary results of <span class="hlt">direct</span> <span class="hlt">observation</span> of Majorana QPs by a precise measurements of superfluid 3He heat capacity. The bulk superfluid 3He heat capacity falls exponentially with cooling at the temperatures significantly below the energy gap. Owing to the zero energy gap mode the Majorana heat capacity falls in a power law. The Majorana heat capacity can be larger than bulk one at some temperature, which depends on surface to volume ratio of the experimental cell. Some times ago we developed the Dark matter particles detector (DMD) on a basis of superfluid 3He which is working at the frontier of extremely low temperatures (Winkelmann et al., Nucl. Instrum. Meth. A 559:384-386, 2006). Here we report the <span class="hlt">observation</span> of zero gap mode of Majorana, follows from the new analyses of DMD heat capacity, published early. We have found a 10 % deviation from the bulk superfluid 3He heat capacity at the temperature of 135 ?K. This deviation corresponds well to the theoretical value for Majorana heat capacity at such low temperature. (Note, there were no fitting parameters).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26263495','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26263495"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> by using Brewster angle microscopy of the diacetylene polimerization in mixed Langmuir film.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ariza-Carmona, Luisa; Martín-Romero, María T; Giner-Casares, Juan J; Camacho, Luis</p> <p>2015-12-01</p> <p>Mixed Langmuir monolayers of 10,12-Pentacosadiynoic acid (DA) and amphiphilic hemicyanine (HSP) have been fabricated at the air-water interface. The mixed monolayer has been proved to be completely homogeneous. The DA molecules are arranged in a single monolayer within the mixed Langmuir monolayer, as opposed to the typical trilayer architecture for the pure DA film. Brewster angle microscopy has been used to reveal the mesoscopic structure of the mixed Langmuir monolayer. Flower shape domains with internal anisotropy due the ordered alignment of hemicyanine groups have been <span class="hlt">observed</span>. Given the absorption features of the hemicyanine groups at the wavelength used in the BAM experiments, the enhancement of reflection provoked by the absorption process leads to the <span class="hlt">observed</span> anisotropy. The ordering of such groups is promoted by their strong self-aggregation tendency. Under UV irradiation at the air-water interface, polydiacetylene (PDA) has been fabricated. In spite a significant increase in the domains reflectivity has been <span class="hlt">observed</span> owing to the modification in the mentioned enhanced reflection, the texture of the domains remains equal. The PDA polymer chain therefore grows in the same <span class="hlt">direction</span> in which the HSP molecules are aligned. This study is expected to enrich the understanding and design of fabrication of PDA at interfaces. PMID:26263495</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6326E..2AP','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6326E..2AP"><span id="translatedtitle">Chemotaxis study using optical tweezers to <span class="hlt">observe</span> the strength and <span class="hlt">directionality</span> of forces of Leishmania amazonensis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pozzo, Liliana d. Y.; Fontes, Adriana; de Thomaz, André A.; Barbosa, Luiz C.; Ayres, Diana C.; Giorgio, Selma; Cesar, Carlos L.</p> <p>2006-08-01</p> <p>The displacements of a dielectric microspheres trapped by an optical tweezers (OT) can be used as a force transducer for mechanical measurements in life sciences. This system can measure forces on the 50 femto Newtons to 200 pico Newtons range, of the same order of magnitude of a typical forces induced by flagellar motion. The process in which living microorganisms search for food and run away from poison chemicals is known is chemotaxy. Optical tweezers can be used to obtain a better understanding of chemotaxy by <span class="hlt">observing</span> the force response of the microorganism when placed in a gradient of attractors and or repelling chemicals. This report shows such <span class="hlt">observations</span> for the protozoa Leishmania amazomenzis, responsible for the leishmaniasis, a serious tropical disease. We used a quadrant detector to monitor the movement of the protozoa for different chemicals gradient. This way we have been able to <span class="hlt">observe</span> both the force strength and its <span class="hlt">directionality</span>. The characterization of the chemotaxis of these parasites can help to understand the infection mechanics and improve the diagnosis and the treatments employed for this disease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Cctv&pg=4&id=ED001362','ERIC'); return false;" href="http://eric.ed.gov/?q=Cctv&pg=4&id=ED001362"><span id="translatedtitle">THE EFFECTIVENESS OF CLOSED CIRCUIT TELEVISION <span class="hlt">OBSERVATION</span> AND OF <span class="hlt">DIRECT</span> <span class="hlt">OBSERVATION</span> OF CHILDREN'S ART CLASSES FOR IMPLEMENTING ELEMENTARY TEACHERS' TRAINING IN ART EDUCATION.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>SYKES, RONALD E.</p> <p></p> <p>AN EXPERIMENTAL STUDY WAS DESIGNED TO MEASURE THE EXTENT TO WHICH CLOSED CIRCUIT TELEVISION <span class="hlt">OBSERVATIONS</span> AND <span class="hlt">DIRECT</span> <span class="hlt">OBSERVATIONS</span> OF CHILDREN'S ART CLASSES CONTRIBUTE SIGNIFICANTLY TO THE ABILITY OF ELEMENTARY EDUCATION MAJORS TO DISCRIMINATE BETWEEN DESIRABLE AND UNDESIRABLE SOLUTIONS TYPICALLY OCCURRING IN TEACHING ART TO ELEMENTARY SCHOOL…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26505325','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26505325"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of American eels migrating across the continental shelf to the Sargasso Sea.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Béguer-Pon, Mélanie; Castonguay, Martin; Shan, Shiliang; Benchetrit, José; Dodson, Julian J</p> <p>2015-01-01</p> <p>Since inferring spawning areas from larval distributions in the Sargasso Sea a century ago, the oceanic migration of adult American eels has remained a mystery. No adult eel has ever been <span class="hlt">observed</span> migrating in the open ocean or in the spawning area. Here, we track movements of maturing eels equipped with pop-up satellite archival tags from the Scotian Shelf (Canada) into the open ocean, with one individual migrating 2,400?km to the northern limit of the spawning site in the Sargasso Sea. The reconstructed routes suggest a migration in two phases: one over the continental shelf and along its edge in shallow waters; the second in deeper waters straight south towards the spawning area. This study is the first <span class="hlt">direct</span> evidence of adult Anguilla migrating to the Sargasso Sea and represents an important step forward in the understanding of routes and migratory cues. PMID:26505325</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1188901','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1188901"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Sulfur Radicals as Reaction Media in lithium Sulfur Batteries</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, Qiang; Zheng, Jianming; Walter, Eric D.; Pan, Huilin; Lu, Dongping; Zuo, Pengjian; Chen, Honghao; Deng, Zhiqun; Liaw, Bor Yann; Yu, Xiqian; Yang, Xiaoning; Zhang, Jiguang; Liu, Jun; Xiao, Jie</p> <p>2014-12-09</p> <p>Lithium sulfur (Li-S) battery has been regaining tremendous interest in recent years because of its attractive attributes such as high gravimetric energy, low cost and environmental benignity. However, it is still not conclusively known how polysulfide ring/chain participates in the whole cycling and whether the discharge and charge process follow the same pathway. Herein, we demonstrate the <span class="hlt">direct</span> <span class="hlt">observation</span> of sulfur radicals by using in situ electron paramagnetic resonance (EPR) technique. Based on the concentration changes of sulfur radicals at different potentials, it is revealed that the chemical and electrochemical reactions in Li-S cell are driven each other to proceed through sulfur radicals, leading to two completely different reaction pathways during discharge and charge. The proposed radical mechanism may provide new insights to investigate the interactions between sulfur species and the electrolyte, inspiring novel strategies to develop Li-S battery technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1169566','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1169566"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Sulfur Radicals as Reaction Media in Lithium Sulfur Batteries</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, Qiang; Zheng, Jianming; Walter, Eric; Pan, Huilin; Lv, Dongping; Zuo, Pengjian; Chen, Honghao; Deng, Z. D.; Liaw, Bor Y.; Yu, Xiqian; Yang, Xiao-Qing; Zhang, Ji-Guang; Liu, Jun; Xiao, Jie</p> <p>2015-01-09</p> <p>Lithium sulfur (Li-S) battery has been regaining tremendous interest in recent years because of its attractive attributes such as high gravimetric energy, low cost and environmental benignity. However, it is still not conclusively known how polysulfide ring/chain participates in the whole cycling and whether the discharge and charge processes follow the same pathway. Herein, we demonstrate the <span class="hlt">direct</span> <span class="hlt">observation</span> of sulfur radicals by using in situ electron paramagnetic resonance (EPR) technique. Based on the concentration changes of sulfur radicals at different potentials and the electrochemical characteristics of the cell, it is revealed that the chemical and electrochemical reactions in Li-S cell are driving each other to proceed through sulfur radicals, leading to two completely different reaction pathways during discharge and charge. The proposed radical mechanism may provide new perspectives to investigate the interactions between sulfur species and the electrolyte, inspiring novel strategies to develop Li-S battery technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26680192','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26680192"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of collective modes coupled to molecular orbital-driven charge transfer.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ishikawa, Tadahiko; Hayes, Stuart A; Keskin, Sercan; Corthey, Gastón; Hada, Masaki; Pichugin, Kostyantyn; Marx, Alexander; Hirscht, Julian; Shionuma, Kenta; Onda, Ken; Okimoto, Yoichi; Koshihara, Shin-ya; Yamamoto, Takashi; Cui, Hengbo; Nomura, Mitsushiro; Oshima, Yugo; Abdel-Jawad, Majed; Kato, Reizo; Miller, R J Dwayne</p> <p>2015-12-18</p> <p>Correlated electron systems can undergo ultrafast photoinduced phase transitions involving concerted transformations of electronic and lattice structure. Understanding these phenomena requires identifying the key structural modes that couple to the electronic states. We report the ultrafast photoresponse of the molecular crystal Me4P[Pt(dmit)2]2, which exhibits a photoinduced charge transfer similar to transitions between thermally accessible states, and demonstrate how femtosecond electron diffraction can be applied to <span class="hlt">directly</span> <span class="hlt">observe</span> the associated molecular motions. Even for such a complex system, the key large-amplitude modes can be identified by eye and involve a dimer expansion and a librational mode. The dynamics are consistent with the time-resolved optical study, revealing how the electronic, molecular, and lattice structures together facilitate ultrafast switching of the state. PMID:26680192</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4432630','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4432630"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of finite size effects in chains of antiferromagnetically coupled spins</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Guidi, T.; Gillon, B.; Mason, S. A.; Garlatti, E.; Carretta, S.; Santini, P.; Stunault, A.; Caciuffo, R.; van Slageren, J.; Klemke, B.; Cousson, A.; Timco, G. A.; Winpenny, R. E. P.</p> <p>2015-01-01</p> <p>Finite spin chains made of few magnetic ions are the ultimate-size structures that can be engineered to perform spin manipulations for quantum information devices. Their spin structure is expected to show finite size effects and its knowledge is of great importance both for fundamental physics and applications. Until now a <span class="hlt">direct</span> and quantitative measurement of the spatial distribution of the magnetization of such small structures has not been achieved even with the most advanced microscopic techniques. Here we present measurements of the spin density distribution of a finite chain of eight spin-3/2 ions using polarized neutron diffraction. The data reveal edge effects that are a consequence of the finite size and of the parity of the chain and indicate a noncollinear spin arrangement. This is in contrast with the uniform spin distribution <span class="hlt">observed</span> in the parent closed chain and the collinear arrangement in odd-open chains. PMID:25952539</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23624696','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23624696"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> and dynamics of spontaneous skyrmion-like magnetic domains in a ferromagnet.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nagao, Masahiro; So, Yeong-Gi; Yoshida, Hiroyuki; Isobe, Masaaki; Hara, Toru; Ishizuka, Kazuo; Kimoto, Koji</p> <p>2013-05-01</p> <p>The structure and dynamics of submicrometre magnetic domains are the main factors determining the physical properties of magnetic materials. Here, we report the first <span class="hlt">observation</span> of skyrmion-like magnetic nanodomains in a ferromagnetic manganite, La0.5Ba0.5MnO3, using Lorentz transmission electron microscopy (LTEM). The skyrmion-like magnetic domains appear as clusters above the Curie temperature. We found that the repeated reversal of magnetic chirality is caused by thermal fluctuation. The closely spaced clusters exhibit dynamic coupling, and the repeated magnetization reversal becomes fully synchronized with the same chirality. Quantitative analysis of such dynamics was performed by LTEM to <span class="hlt">directly</span> determine the barrier energy for the magnetization reversal of skyrmion-like nanometre domains. This study is expected to pave the way for further investigation of the unresolved nature and dynamics of magnetic vortex-like nanodomains. PMID:23624696</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..MARM21005M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..MARM21005M"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of intrinsic localized modes as precursors to polar nanoregions in a relaxor ferroelectric</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Manley, Michael; Delaire, Olivier; Lynn, Jeffrey; Bishop, Alan; Sahul, Raffi; Budai, John</p> <p>2013-03-01</p> <p>Displacive ferroelectric phase transitions can be understood in terms of a soft zone center phonon tending towards zero frequency as the material is cooled towards the transition. Relaxor ferroelectrics are less well understood but there is a growing consensus that dispersed polar nanoregions (PNRs), pinned by chemical inhomogeneities, are responsible for the behavior. Furthermore, it has been argued that PNRs form via soft localized phonon modes, modeled as intrinsic localized modes (ILMs), tending towards zero frequency as the material is cooled into the relaxor region, but these modes have never been <span class="hlt">observed</span> <span class="hlt">directly</span>. In this talk, neutron scattering measurements will be presented that reveal the existence of a dispersionless (localized) mode appearing near the Burns temperature in PMN-PT. The local mode softens and diminishes in intensity on cooling towards the relaxor region, ultimately vanishing as the PNRs form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1169566-direct-observation-sulfur-radicals-reaction-media-lithium-sulfur-batteries','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1169566-direct-observation-sulfur-radicals-reaction-media-lithium-sulfur-batteries"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Sulfur Radicals as Reaction Media in Lithium Sulfur Batteries</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Wang, Qiang; Zheng, Jianming; Walter, Eric; Pan, Huilin; Lv, Dongping; Zuo, Pengjian; Chen, Honghao; Deng, Z. D.; Liaw, Bor Y.; Yu, Xiqian; et al</p> <p>2015-01-09</p> <p>Lithium sulfur (Li-S) battery has been regaining tremendous interest in recent years because of its attractive attributes such as high gravimetric energy, low cost and environmental benignity. However, it is still not conclusively known how polysulfide ring/chain participates in the whole cycling and whether the discharge and charge processes follow the same pathway. Herein, we demonstrate the <span class="hlt">direct</span> <span class="hlt">observation</span> of sulfur radicals by using in situ electron paramagnetic resonance (EPR) technique. Based on the concentration changes of sulfur radicals at different potentials and the electrochemical characteristics of the cell, it is revealed that the chemical and electrochemical reactions in Li-Smore »cell are driving each other to proceed through sulfur radicals, leading to two completely different reaction pathways during discharge and charge. The proposed radical mechanism may provide new perspectives to investigate the interactions between sulfur species and the electrolyte, inspiring novel strategies to develop Li-S battery technology.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24384687','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24384687"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of hierarchical nucleation of martensite and size-dependent superelasticity in shape memory alloys.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Lifeng; Ding, Xiangdong; Li, Ju; Lookman, Turab; Sun, Jun</p> <p>2014-02-21</p> <p>Martensitic transformation usually creates hierarchical internal structures beyond mere change of the atomic crystal structure. Multi-stage nucleation is thus required, where nucleation (level-1) of the underlying atomic crystal lattice does not have to be immediately followed by the nucleation of higher-order superstructures (level-2 and above), such as polysynthetic laths. Using in situ transmission electron microscopy (TEM), we <span class="hlt">directly</span> <span class="hlt">observe</span> the nucleation of the level-2 superstructure in a Cu-Al-Ni single crystal under compression, with critical super-nuclei size L2c around 500 nm. When the sample size D decreases below L2c, the superelasticity behavior changes from a flat stress plateau to a continuously rising stress-strain curve. Such size dependence definitely would impact the application of shape memory alloys in miniaturized MEMS/NEMS devices. PMID:24384687</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004JMoSt.700...13L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004JMoSt.700...13L"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the nuclear motion during ultrafast intramolecular proton transfer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lochbrunner, S.; Stock, K.; Riedle, E.</p> <p>2004-08-01</p> <p>The skeletal motions contributing to the reaction path of the ultrafast excited state intramolecular proton transfer (ESIPT) are determined <span class="hlt">directly</span> from time resolved measurements. We investigate the ESIPT in the compounds 2-(2'-hydroxyphenyl)benzothiazole, 2-(2'-hydroxyphenyl)benzoxazole and ortho-hydroxybenzaldehyde by UV-visible pump-probe spectroscopy with 30 fs resolution. The proton transfer is <span class="hlt">observed</span> in real time and a characteristic 'ringing' of the molecule in a small number of vibrational modes is found after the reaction. The results show that a bending motion of the molecular skeleton reduces the proton donor-acceptor distance and an electronic configuration change occurs at a sufficient contraction leading to the bonds of the product conformer. The process evolves as a ballistic wavepacket propagation on an adiabatic potential energy surface. The proton is shifted by the skeletal motions from the donor to the acceptor site and tunneling has not to be considered.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NanoL..15.4429K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NanoL..15.4429K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of a Gate Tunable Band Gap in Electrical Transport in ABC-Trilayer Graphene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khodkov, Tymofiy; Khrapach, Ivan; Craciun, Monica Felicia; Russo, Saverio</p> <p>2015-07-01</p> <p>Few layer graphene systems such as Bernal stacked bilayer and rhombohedral (ABC-) stacked trilayer offer the unique possibility to open an electric field tunable energy gap. To date, this energy gap has been experimentally confirmed in optical spectroscopy. Here we report the first <span class="hlt">direct</span> <span class="hlt">observation</span> of the electric field tunable energy gap in electronic transport experiments on doubly gated suspended ABC-trilayer graphene. From a systematic study of the non-linearities in current \\textit{versus} voltage characteristics and the temperature dependence of the conductivity we demonstrate that thermally activated transport over the energy-gap dominates the electrical response of these transistors. The estimated values for energy gap from the temperature dependence and from the current voltage characteristics follow the theoretically expected electric field dependence with critical exponent $3/2$. These experiments indicate that high quality few-layer graphene are suitable candidates for exploring novel tunable THz light sources and detectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1446511','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1446511"><span id="translatedtitle">A novel approach to <span class="hlt">directly</span> <span class="hlt">observed</span> therapy for tuberculosis in an HIV-endemic area.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Desvarieux, M; Hyppolite, P R; Johnson, W D; Pape, J W</p> <p>2001-01-01</p> <p>OBJECTIVES: This study evaluated a novel approach to the delivery of <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (DOT) for tuberculosis in Haiti. METHODS: A total of 194 patients (152 HIV seropositive, 42 HIV seronegative) received daily unsupervised triple-drug therapy for 4 to 8 weeks, followed by twice-weekly 2-drug therapy for the remainder of the 6-month period. DOT was deferred until initiation of the twice-weekly phase. RESULTS: A total of 169 of 194 patients (87.1%) completed the 6-month course. The program of deferred DOT had an effectiveness of 85%. Overall cost was reduced by approximately 40%. CONCLUSIONS: Flexible approaches to DOT, integrating behavioral knowledge, cost considerations, and practicality may improve completion rates and program effectiveness. PMID:11189809</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24321934','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24321934"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of Kramers-Kronig self-phasing in coherently combined fiber lasers.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chiang, Hung-Sheng; Leger, James R; Nilsson, Johan; Sahu, Jayanta</p> <p>2013-10-15</p> <p>A highly stable coherent beam-combining system has been designed to measure self-phasing in fiber lasers due to nonlinear effects. Whereas self-phasing in previous coherent combination experiments has been principally attributed to wavelength shifting, these wavelength effects have been efficiently suppressed in our experiment by using a dual-core fiber with closely balanced optical path lengths. The self-phasing from nonlinear effects could then be measured independently and <span class="hlt">directly</span> by common-path interferometry with a probe laser. The Kramers-Kronig effect in the fiber gain media was <span class="hlt">observed</span> to induce a phase shift that effectively canceled the applied path length errors, resulting in efficient lasing under all phase conditions. This process was demonstrated to result in robust lasing over a large range of pump conditions. PMID:24321934</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23004598','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23004598"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the hyperfine transition of ground-state positronium.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yamazaki, T; Miyazaki, A; Suehara, T; Namba, T; Asai, S; Kobayashi, T; Saito, H; Ogawa, I; Idehara, T; Sabchevski, S</p> <p>2012-06-22</p> <p>We report the first <span class="hlt">direct</span> measurement of the hyperfine transition of the ground state positronium. The hyperfine structure between ortho-positronium and para-positronium is about 203 GHz. We develop a new optical system to accumulate about 10 kW power using a gyrotron, a mode converter, and a Fabry-Pérot cavity. The hyperfine transition has been <span class="hlt">observed</span> with a significance of 5.4 standard deviations. The transition probability is measured to be A = 3.1(-1.2)(+1.6) × 10(-8) s(-1) for the first time, which is in good agreement with the theoretical value of 3.37 × 10(-8) s(-1). PMID:23004598</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1002501','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1002501"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Morphological Tranformation from Twisted Ribbons into Helical Ribbons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pashuck, E.Thomas; Stupp, Samuel I.</p> <p>2010-07-01</p> <p>We report on the <span class="hlt">direct</span> <span class="hlt">observation</span> of a nanostructural transformation from a twisted ribbon to a helical ribbon in supramolecular assemblies of peptide amphiphiles. Using cryogenic electron microscopy, a peptide amphiphile molecule containing aromatic residues was found to first assemble into short twisted ribbons in the time range of seconds, which then elongate in the time scale of minutes, and finally transform into helical ribbons over the course of weeks. By synthesizing an analogous molecule without the aromatic side groups, it was found that a cylindrical nanostructure is formed that does not undergo any transitions during the same time period. The study of metastable states in peptide aggregation can contribute to our understanding of amyloid-related diseases, such as Alzheimer's disease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24875774','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24875774"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of half-metallicity in the Heusler compound Co2MnSi.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jourdan, M; Minár, J; Braun, J; Kronenberg, A; Chadov, S; Balke, B; Gloskovskii, A; Kolbe, M; Elmers, H J; Schönhense, G; Ebert, H; Felser, C; Kläui, M</p> <p>2014-01-01</p> <p>Ferromagnetic thin films of Heusler compounds are highly relevant for spintronic applications owing to their predicted half-metallicity, that is, 100% spin polarization at the Fermi energy. However, experimental evidence for this property is scarce. Here we investigate epitaxial thin films of the compound Co2MnSi in situ by ultraviolet-photoemission spectroscopy, taking advantage of a novel multi-channel spin filter. By this surface sensitive method, an exceptionally large spin polarization of (93(-11)(+7)) % at room temperature is <span class="hlt">observed</span> <span class="hlt">directly</span>. As a more bulk sensitive method, additional ex situ spin-integrated high energy X-ray photoemission spectroscopy experiments are performed. All experimental results are compared with advanced band structure and photoemission calculations which include surface effects. Excellent agreement is obtained with calculations, which show a highly spin polarized bulk-like surface resonance ingrained in a half metallic bulk band structure. PMID:24875774</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1984Natur.307...58Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1984Natur.307...58Y"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of motion of single F-actin filaments in the presence of myosin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yanagida, Toshio; Nakase, Michiyuki; Nishiyama, Katsumi; Oosawa, Fumio</p> <p>1984-01-01</p> <p>Actin is found in almost all kinds of non-muscle cells where it is thought to have an important role in cell motility. A proper understanding of that role will only be possible when reliable in vitro systems are available for investigating the interaction of cellular actin and myosin. A start has been made on several systems1-4, most recently by Sheetz and Spudich who demonstrated unidirectional movement of HMM-coated beads along F-actin cables on arrays of chloroplasts exposed by dissection of a Nitella cell5. As an alternative approach, we report here the <span class="hlt">direct</span> <span class="hlt">observation</span> by fluorescence microscopy of the movements of single F-actin filaments interacting with soluble myosin fragments energized by Mg2+-ATP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3603292','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3603292"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Ion Distributions near Electrodes in Ionic Polymer Actuators Containing Ionic Liquids</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Yang; Lu, Caiyan; Twigg, Stephen; Ghaffari, Mehdi; Lin, Junhong; Winograd, Nicholas; Zhang, Q. M.</p> <p>2013-01-01</p> <p>The recent boom of energy storage and conversion devices, exploiting ionic liquids (ILs) to enhance the performance, requires an in-depth understanding of this new class of electrolytes in device operation conditions. One central question critical to device performance is how the mobile ions accumulate near charged electrodes. Here, we present the excess ion depth profiles of ILs in ionomer membrane actuators (Aquivion/1-butyl-2,3-dimethylimidazolium chloride (BMMI-Cl), 27??m thick), characterized <span class="hlt">directly</span> by Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) at liquid nitrogen temperature. Experimental results reveal that for the IL studied, cations and anions are accumulated at both electrodes. The large difference in the total volume occupied by the excess ions between the two electrodes cause the <span class="hlt">observed</span> large bending actuation of the actuator. Hence we demonstrate that ToF-SIMS experiment provides great insights on the physics nature of ionic devices. PMID:23512124</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4050270','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4050270"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of half-metallicity in the Heusler compound Co2MnSi</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jourdan, M.; Minár, J.; Braun, J.; Kronenberg, A.; Chadov, S.; Balke, B.; Gloskovskii, A.; Kolbe, M.; Elmers, H.J.; Schönhense, G.; Ebert, H.; Felser, C.; Kläui, M.</p> <p>2014-01-01</p> <p>Ferromagnetic thin films of Heusler compounds are highly relevant for spintronic applications owing to their predicted half-metallicity, that is, 100% spin polarization at the Fermi energy. However, experimental evidence for this property is scarce. Here we investigate epitaxial thin films of the compound Co2MnSi in situ by ultraviolet-photoemission spectroscopy, taking advantage of a novel multi-channel spin filter. By this surface sensitive method, an exceptionally large spin polarization of () % at room temperature is <span class="hlt">observed</span> <span class="hlt">directly</span>. As a more bulk sensitive method, additional ex situ spin-integrated high energy X-ray photoemission spectroscopy experiments are performed. All experimental results are compared with advanced band structure and photoemission calculations which include surface effects. Excellent agreement is obtained with calculations, which show a highly spin polarized bulk-like surface resonance ingrained in a half metallic bulk band structure. PMID:24875774</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMMR51A..04C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMMR51A..04C"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of gas-hydrate formation in natural porous media on the micro-scale</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chaouachi, M.; Sell, K.; Falenty, A.; Enzmann, F.; Kersten, M.; Pinzer, B.; Saenger, E. H.; Kuhs, W. F.</p> <p>2013-12-01</p> <p>Gas hydrates (GH) are crystalline, inclusion compounds consisting of hydrogen-bonded water network encaging small gas molecules such as methane, ethane, CO2, etc (Sloan and Koh 2008). Natural gas hydrates are found worldwide in marine sediments and permafrost regions as a result of a reaction of biogenic or thermogenic gas with water under elevated pressure. Although a large amount of research on GH has been carried out over the years, the micro-structural aspects of GH growth, and in particular the contacts with the sedimentary matrix as well as the details of the distribution remain largely speculative. The present study was undertaken to shed light onto the well-established but not fully understood seismic anomalies, in particular the unusual attenuation of seismic waves in GH-bearing sediments, which may well be linked to micro-structural features. <span class="hlt">Observations</span> of in-situ GH growth have been performed in a custom-build pressure cell (operating pressures up to several bar) mounted at the TOMCAT beam line of SLS/ PSI. In order to provide sufficient absorption contrast between phases and reduce pressure requirements for the cell we have used Xe instead of CH4. To the best of our knowledge this represents the first <span class="hlt">direct</span> <span class="hlt">observation</span> of GH growth in natural porous media with sub-micron spatial resolution and gives insight into the nucleation location and growth process of GH. The progress of the formation of sI Xe-hydrate in natural quartz sand was <span class="hlt">observed</span> with a time-resolution of several minutes; the runs were conducted with an excess of a free-gas phase and show that the nucleation starts at the gas-water interface. Initially, a GH film is formed at this interface with a typical thickness of several ?m; this film may well be permeable to gas as suggested in the past - which would explain the rapid transport of gas molecules for further conversion of water to hydrate, completed in less than 20 min. Clearly, initially the growth is <span class="hlt">directed</span> mainly into the liquid (and not into the gas phase as sometimes suggested). The <span class="hlt">observations</span> of the 2D slices after full transformation show for all systems studied that hydrates tend to concentrate in the center of pore spaces and do not adhere in a systematic manner to quartz grains. Whether or not a thin film of water remained at the quartz-GH interface after completion of the reaction is presently under investigation. Sloan, E.D., Koh, C.A., (2008) Clathrate hydrates of natural gases. CRC Press, Boca Raton, FL.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Nanos...6.2067L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Nanos...6.2067L"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of hierarchical nucleation of martensite and size-dependent superelasticity in shape memory alloys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Lifeng; Ding, Xiangdong; Li, Ju; Lookman, Turab; Sun, Jun</p> <p>2014-01-01</p> <p>Martensitic transformation usually creates hierarchical internal structures beyond mere change of the atomic crystal structure. Multi-stage nucleation is thus required, where nucleation (level-1) of the underlying atomic crystal lattice does not have to be immediately followed by the nucleation of higher-order superstructures (level-2 and above), such as polysynthetic laths. Using in situ transmission electron microscopy (TEM), we <span class="hlt">directly</span> <span class="hlt">observe</span> the nucleation of the level-2 superstructure in a Cu-Al-Ni single crystal under compression, with critical super-nuclei size L2c around 500 nm. When the sample size D decreases below L2c, the superelasticity behavior changes from a flat stress plateau to a continuously rising stress-strain curve. Such size dependence definitely would impact the application of shape memory alloys in miniaturized MEMS/NEMS devices.Martensitic transformation usually creates hierarchical internal structures beyond mere change of the atomic crystal structure. Multi-stage nucleation is thus required, where nucleation (level-1) of the underlying atomic crystal lattice does not have to be immediately followed by the nucleation of higher-order superstructures (level-2 and above), such as polysynthetic laths. Using in situ transmission electron microscopy (TEM), we <span class="hlt">directly</span> <span class="hlt">observe</span> the nucleation of the level-2 superstructure in a Cu-Al-Ni single crystal under compression, with critical super-nuclei size L2c around 500 nm. When the sample size D decreases below L2c, the superelasticity behavior changes from a flat stress plateau to a continuously rising stress-strain curve. Such size dependence definitely would impact the application of shape memory alloys in miniaturized MEMS/NEMS devices. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr05258c</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AAS...21348902T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AAS...21348902T"><span id="translatedtitle"><span class="hlt">Direct</span> Analysis of Type Ia Supernovae <span class="hlt">Observed</span> by The Nearby Supernova Factory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thomas, Rollin; Aldering, G.; Antilogus, P.; Aragon, C.; Bailey, S.; Baltay, C.; Bongard, S.; Buton, C.; Childress, M.; Copin, Y.; Gangler, E.; Jerke, J.; Loken, S.; Nugent, P.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigaudier, G.; Ripoche, P.; Runge, K.; Scalzo, R.; Smadja, G.; Swift, H.; Tao, C.; Wu, C.</p> <p>2009-01-01</p> <p>Over the past four years, the Nearby Supernova Factory (SNfactory) has obtained hundreds of time-series spectra of Type Ia supernovae (SNe Ia) using its SuperNova Integral Field Spectrograph (SNIFS). This dataset is a promising resource for improving our understanding of SN Ia explosion physics and progenitor models --- key issues that, if resolved, could further improve the utility of and confidence in SNe Ia as reliable cosmological distance indicators. Using a new, automated <span class="hlt">direct</span> analysis code we have developed (SYNAPPS), we have commenced a systematic study of the SNfactory spectroscopic data set. SYNAPPS solves for a highly parameterized synthetic spectrum consistent with the <span class="hlt">observed</span> spectrum, enabling line identification and ejecta velocity measurements, while treating line-blending explicitly. These results provide important constraints on stellar explosion models. We present preliminary results including, for example, an investigation of some early-phase spectra, and examine trends in spectral behavior noted previously by others. We also address future <span class="hlt">directions</span> for code development to bring about a deeper physics analysis of the data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ERL....10j4005L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ERL....10j4005L"><span id="translatedtitle"><span class="hlt">Direct</span> radiative feedback due to biogenic secondary organic aerosol estimated from boreal forest site <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lihavainen, Heikki; Asmi, Eija; Aaltonen, Veijo; Makkonen, Ulla; Kerminen, Veli-Matti</p> <p>2015-10-01</p> <p>We used more than five years of continuous aerosol measurements to estimate the <span class="hlt">direct</span> radiative feedback parameter associated with the formation of biogenic secondary organic aerosol (BSOA) at a remote continental site at the edge of the boreal forest zone in Northern Finland. Our upper-limit estimate for this feedback parameter during the summer period (ambient temperatures above 10 °C) was -97 ± 66 mW m-2 K-1 (mean ± STD) when using measurements of the aerosol optical depth (fAOD) and -63 ± 40 mW m-2 K-1 when using measurements of the ‘dry’ aerosol scattering coefficient at the ground level (f?). Here STD represents the variability in f caused by the <span class="hlt">observed</span> variability in the quantities used to derive the value of f. Compared with our measurement site, the magnitude of the <span class="hlt">direct</span> radiative feedback associated with BSOA is expected to be larger in warmer continental regions with more abundant biogenic emissions, and even larger in regions where biogenic emissions are mixed with anthropogenic pollution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007APS..MARH28006L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007APS..MARH28006L"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of Landau levels of massless and massive Dirac fermions.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Guohong; Andrei, Eva Y.</p> <p>2007-03-01</p> <p>The low energy quasiparticles in graphene resemble massless relativistic particles (Dirac fermions): they have a linear energy-momentum spectrum and possess internal degrees of freedom arising from the crystal symmetry of the honeycomb lattice, leading to particle anti-particle pairs. When two layers of graphene are coupled together, the quasiparticles acquire a band-mass and are transformed into chiral massive fermions. Both types of quasiparticles develop unusual Landau levels in a magnetic field which profoundly alter the magneto-transport properties. We will report the <span class="hlt">direct</span> <span class="hlt">observation</span> of the Landau levels associated with these quasiparticles using a low temperature STM in fields up to 12 Tesla. The experiments reveal two independent sequences of Landau levels that provide evidence for the coexistence of massless and massive Dirac fermions. The energy levels of the former exhibit a square-root dependence on both field and Landau-level index n, while the latter are linear in field with a Landau-level index dependence of [n(n+1)]^1/2. Both sequences exhibit a zero energy Landau level which is a unique and <span class="hlt">direct</span> consequence of the quantum-relativistic nature of these quasiparticles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=15137','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=15137"><span id="translatedtitle">Ultrafast electron diffraction and <span class="hlt">direct</span> <span class="hlt">observation</span> of transient structures in a chemical reaction</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cao, Jianming; Ihee, Hyotcherl; Zewail, Ahmed H.</p> <p>1999-01-01</p> <p>Ultrafast electron diffraction is a unique method for the studies of structural changes of complex molecular systems. In this contribution, we report <span class="hlt">direct</span> ultrafast electron diffraction study of the evolution of short-lived intermediates in the course of a chemical change. Specifically, we <span class="hlt">observe</span> the transient intermediate in the elimination reaction of 1,2-diiodotetrafluoroethane (C2F4I2) to produce the corresponding ethylene derivative by the breakage of two carbon–iodine, C—I, bonds. The evolution of the ground-state intermediate (C2F4I radical) is <span class="hlt">directly</span> revealed in the population change of a single chemical bond, namely the second C—I bond. The elimination of two iodine atoms was shown to be nonconcerted, with reaction time of the second C—I bond breakage being 17 ± 2 ps. The structure of the short-lived C2F4I radical is more favorable to the classical radical structure than to the bridged radical structure. This leap in our ability to record structural changes on the ps and shorter time scales bodes well for many future applications in complex molecular systems. PMID:9892634</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4246975','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4246975"><span id="translatedtitle"><span class="hlt">Direct</span> single-molecule <span class="hlt">observation</span> of calcium-dependent misfolding in human neuronal calcium sensor-1</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Heidarsson, Pétur O.; Naqvi, Mohsin M.; Otazo, Mariela R.; Mossa, Alessandro; Kragelund, Birthe B.; Cecconi, Ciro</p> <p>2014-01-01</p> <p>Neurodegenerative disorders are strongly linked to protein misfolding, and crucial to their explication is a detailed understanding of the underlying structural rearrangements and pathways that govern the formation of misfolded states. Here we use single-molecule optical tweezers to monitor misfolding reactions of the human neuronal calcium sensor-1, a multispecific EF-hand protein involved in neurotransmitter release and linked to severe neurological diseases. We <span class="hlt">directly</span> <span class="hlt">observed</span> two misfolding trajectories leading to distinct kinetically trapped misfolded conformations. Both trajectories originate from an on-pathway intermediate state and compete with native folding in a calcium-dependent manner. The relative probability of the different trajectories could be affected by modulating the relaxation rate of applied force, demonstrating an unprecedented real-time control over the free-energy landscape of a protein. Constant-force experiments in combination with hidden Markov analysis revealed the free-energy landscape of the misfolding transitions under both physiological and pathological calcium concentrations. Remarkably for a calcium sensor, we found that higher calcium concentrations increased the lifetimes of the misfolded conformations, slowing productive folding to the native state. We propose a rugged, multidimensional energy landscape for neuronal calcium sensor-1 and speculate on a <span class="hlt">direct</span> link between protein misfolding and calcium dysregulation that could play a role in neurodegeneration. PMID:25157171</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25584770','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25584770"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of graphene growth and associated copper substrate dynamics by in situ scanning electron microscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Zhu-Jun; Weinberg, Gisela; Zhang, Qiang; Lunkenbein, Thomas; Klein-Hoffmann, Achim; Kurnatowska, Michalina; Plodinec, Milivoj; Li, Qing; Chi, Lifeng; Schloegl, R; Willinger, Marc-Georg</p> <p>2015-02-24</p> <p>This work highlights the importance of in situ experiments for an improved understanding of graphene growth on copper via metal-catalyzed chemical vapor deposition (CVD). Graphene growth inside the chamber of a modified environmental scanning electron microscope under relevant low-pressure CVD conditions <span class="hlt">allows</span> visualizing structural dynamics of the active catalyst simultaneously with graphene nucleation and growth in an unparalleled way. It enables the <span class="hlt">observation</span> of a complete CVD process from substrate annealing through graphene nucleation and growth and, finally, substrate cooling in real time and nanometer-scale resolution without the need of sample transfer. A strong dependence of surface dynamics such as sublimation and surface premelting on grain orientation is demonstrated, and the influence of substrate dynamics on graphene nucleation and growth is presented. Insights on the growth mechanism are provided by a simultaneous <span class="hlt">observation</span> of the growth front propagation and nucleation rate. Furthermore, the role of trace amounts of oxygen during growth is discussed and related to graphene-induced surface reconstructions during cooling. Above all, this work demonstrates the potential of the method for in situ studies of surface dynamics on active metal catalysts. PMID:25584770</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NaPho...9..674Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NaPho...9..674Y"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of ultraslow hyperbolic polariton propagation with negative phase velocity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yoxall, Edward; Schnell, Martin; Nikitin, Alexey Y.; Txoperena, Oihana; Woessner, Achim; Lundeberg, Mark B.; Casanova, Félix; Hueso, Luis E.; Koppens, Frank H. L.; Hillenbrand, Rainer</p> <p>2015-10-01</p> <p>Polaritons with hyperbolic dispersion are key to many emerging photonic technologies, including subdiffraction imaging, sensing and spontaneous emission engineering. Fundamental to their effective application are the lifetimes of the polaritons, as well as their phase and group velocities. Here, we combine time-domain interferometry and scattering-type near-field microscopy to visualize the propagation of hyperbolic polaritons in space and time, <span class="hlt">allowing</span> the first <span class="hlt">direct</span> measurement of all these quantities. In particular, we study infrared phonon polaritons in a thin hexagonal boron nitride waveguide exhibiting hyperbolic dispersion and deep subwavelength-scale field confinement. Our results reveal—in a natural material—negative phase velocity paired with a remarkably slow group velocity of 0.002c and lifetimes in the picosecond range. While these findings show the polariton's potential for mediating strong light-matter interactions and negative refraction, our imaging technique paves the way to explicit nanoimaging of polariton propagation characteristics in other two-dimensional materials, metamaterials and waveguides.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2077274','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2077274"><span id="translatedtitle">Gossip as an alternative for <span class="hlt">direct</span> <span class="hlt">observation</span> in games of indirect reciprocity</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Sommerfeld, Ralf D.; Krambeck, Hans-Jürgen; Semmann, Dirk; Milinski, Manfred</p> <p>2007-01-01</p> <p>Communication about social topics is abundant in human societies, and many functions have been attributed to such gossiping. One of these proposed functions is the management of reputations. Reputation by itself has been shown to have a strong influence on cooperation dynamics in games of indirect reciprocity, and this notion helps to explain the <span class="hlt">observed</span> high level of cooperation in humans. Here we designed a game to test a widespread assumption that gossip functions as a vector for the transmission of social information. This empirical study (with 14 groups of nine students each) focuses on the composition of gossip, information transfer by gossip, and the behavior based on gossip information. We show that gossip has a strong influence on the resulting behavior even when participants have access to the original information (i.e., <span class="hlt">direct</span> <span class="hlt">observation</span>) as well as gossip about the same information. Thus, it is evident that gossip has a strong manipulative potential. Furthermore, gossip about cooperative individuals is more positive than gossip about uncooperative individuals, gossip comments transmit social information successfully, and cooperation levels are higher when people encounter positive compared with negative gossip. PMID:17947384</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150001455','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150001455"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observations</span> of Evolving Subglacial Drainage Beneath the Greenland Ice Sheet</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Andrews, Lauren C.; Catania, Ginny A.; Hoffman, Matthew J.; Gulley, Jason D.; Luthi, Martin P.; Ryser, Claudia; Hawley, Robert L.; Neumann, Thomas A.</p> <p>2014-01-01</p> <p>Seasonal acceleration of the Greenland Ice Sheet is influenced by the dynamic response of the subglacial hydrologic system to variability in meltwater delivery to the bed via crevasses and moulins (vertical conduits connecting supraglacial water to the bed of the ice sheet). As the melt season progresses, the subglacial hydrologic system drains supraglacial melt water more efficiently,decreasing basal water pressure and moderating the ice velocity response to surface melting.However, limited <span class="hlt">direct</span> <span class="hlt">observations</span> of subglacial water pressure mean that the spatiotemporal evolution of the subglacial hydrologic system remains poorly understood. Here we show that ice velocity is well correlated with moulin hydraulic head but is out of phase with that of nearby (0.3-2 kilometres away) boreholes, indicating that moulins connect to an efficient, channelized component of the subglacial hydrologic system, which exerts the primary control on diurnal and multi-day changes in ice velocity. Our simultaneous measurements of moulin and borehole hydraulic head and ice velocity in the Paakitsoq region of western Greenland show that decreasing trends in ice velocity during the latter part of the melt season cannot be explained by changes in the ability of moulin-connected channels to convey supraglacial melt. Instead, these <span class="hlt">observations</span> suggest that decreasing late-season ice velocity may be caused by changes in connectivity in unchannelized regions of the subglacial hydrologic system.Understanding this spatiotemporal variability in subglacial pressures is increasingly important because melt-season dynamics affect ice velocity beyond the conclusion of the melt season.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20040047265&hterms=mixture&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmixture','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20040047265&hterms=mixture&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmixture"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Controlled Melting and Resolidification of Succinonitrile Mixtures in a Microgravity Environment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Grugel, R. N.; Anilkumar, A. V.; Lee, C. P.</p> <p>2004-01-01</p> <p>In support of the Pore Formation and Mobility Investigation (PFMI) <span class="hlt">direct</span> <span class="hlt">observation</span> of experiments on the controlled melting and subsequent resolidification of succinonitrile were conducted in the glovebox facility (GBX) of the International Space Station (ISS). Samples were prepared on ground by filling glass tubes, 1 cm ID and approximately 30 cm in length, with pure succinonitrile (SCN) and SCN-Water mixtures under 450 millibar of nitrogen. Experimental processing parameters of temperature gradient and translation speed, as well as camera settings, were remotely monitored and manipulated from the ground Telescience Center (TSC) at the Marshall Space Flight Center. Sample temperatures are monitored by six in situ thermocouples. Real time visualization during melt back revealed bubbles of different sizes initiating at the solid/liquid interface, their release, interactions, and movement into the temperature field ahead of them. Subsequent re-solidification examined planar interface breakdown and the transition to steady-state dendritic growth. A preliminary analysis of the <span class="hlt">observed</span> phenomena and its implication to future microgravity experiments is presented and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Natur.514...80A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Natur.514...80A"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of evolving subglacial drainage beneath the Greenland Ice Sheet</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Andrews, Lauren C.; Catania, Ginny A.; Hoffman, Matthew J.; Gulley, Jason D.; Lüthi, Martin P.; Ryser, Claudia; Hawley, Robert L.; Neumann, Thomas A.</p> <p>2014-10-01</p> <p>Seasonal acceleration of the Greenland Ice Sheet is influenced by the dynamic response of the subglacial hydrologic system to variability in meltwater delivery to the bed via crevasses and moulins (vertical conduits connecting supraglacial water to the bed of the ice sheet). As the melt season progresses, the subglacial hydrologic system drains supraglacial meltwater more efficiently, decreasing basal water pressure and moderating the ice velocity response to surface melting. However, limited <span class="hlt">direct</span> <span class="hlt">observations</span> of subglacial water pressure mean that the spatiotemporal evolution of the subglacial hydrologic system remains poorly understood. Here we show that ice velocity is well correlated with moulin hydraulic head but is out of phase with that of nearby (0.3-2 kilometres away) boreholes, indicating that moulins connect to an efficient, channelized component of the subglacial hydrologic system, which exerts the primary control on diurnal and multi-day changes in ice velocity. Our simultaneous measurements of moulin and borehole hydraulic head and ice velocity in the Paakitsoq region of western Greenland show that decreasing trends in ice velocity during the latter part of the melt season cannot be explained by changes in the ability of moulin-connected channels to convey supraglacial melt. Instead, these <span class="hlt">observations</span> suggest that decreasing late-season ice velocity may be caused by changes in connectivity in unchannelized regions of the subglacial hydrologic system. Understanding this spatiotemporal variability in subglacial pressures is increasingly important because melt-season dynamics affect ice velocity beyond the conclusion of the melt season.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25279921','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25279921"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of evolving subglacial drainage beneath the Greenland Ice Sheet.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Andrews, Lauren C; Catania, Ginny A; Hoffman, Matthew J; Gulley, Jason D; Lüthi, Martin P; Ryser, Claudia; Hawley, Robert L; Neumann, Thomas A</p> <p>2014-10-01</p> <p>Seasonal acceleration of the Greenland Ice Sheet is influenced by the dynamic response of the subglacial hydrologic system to variability in meltwater delivery to the bed via crevasses and moulins (vertical conduits connecting supraglacial water to the bed of the ice sheet). As the melt season progresses, the subglacial hydrologic system drains supraglacial meltwater more efficiently, decreasing basal water pressure and moderating the ice velocity response to surface melting. However, limited <span class="hlt">direct</span> <span class="hlt">observations</span> of subglacial water pressure mean that the spatiotemporal evolution of the subglacial hydrologic system remains poorly understood. Here we show that ice velocity is well correlated with moulin hydraulic head but is out of phase with that of nearby (0.3-2 kilometres away) boreholes, indicating that moulins connect to an efficient, channelized component of the subglacial hydrologic system, which exerts the primary control on diurnal and multi-day changes in ice velocity. Our simultaneous measurements of moulin and borehole hydraulic head and ice velocity in the Paakitsoq region of western Greenland show that decreasing trends in ice velocity during the latter part of the melt season cannot be explained by changes in the ability of moulin-connected channels to convey supraglacial melt. Instead, these <span class="hlt">observations</span> suggest that decreasing late-season ice velocity may be caused by changes in connectivity in unchannelized regions of the subglacial hydrologic system. Understanding this spatiotemporal variability in subglacial pressures is increasingly important because melt-season dynamics affect ice velocity beyond the conclusion of the melt season. PMID:25279921</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18260805','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18260805"><span id="translatedtitle">The feasibility of modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy for HIV-seropositive African American substance users.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ma, Mindy; Brown, Billy R; Coleman, Melissa; Kibler, Jeffrey L; Loewenthal, Helen; Mitty, Jennifer A</p> <p>2008-02-01</p> <p>Recently, modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (MDOT) has emerged as a promising intervention to address nonadherence for hard-to-reach populations infected with HIV. To date, there are no existing data on MDOT focusing exclusively on African Americans. The present study sought to determine the feasibility of MDOT among 31 HIV-seropositive African American substance users in the South. An outreach worker <span class="hlt">observed</span> the participants' medication intake 5 days per week (once per day) for a period of 3 months (intensive phase). This phase was followed by a transition phase of 3 months during which the frequency of MDOT was gradually tapered from 5 days to once weekly. Assessments to gather demographic information, HIV risk behaviors, substance use, depression, and medication adherence were conducted at baseline, 3 months, and 6 months. Results indicated that more participants adhered to their medication regimen and had viral loads of less than 400 copies per milliliter at 3 and 6 months compared to baseline. Participants reported significantly less depressive symptoms at the 6-month assessment compared to baseline and 3 months. With regard to acceptability, 95% of participants indicated they liked having the outreach visits, 100% reported MDOT helped them take their medications, and only 5% felt MDOT was a violation of privacy. These results suggest MDOT is feasible among African American substance users in the South and a larger controlled study of MDOT with this population is warranted. PMID:18260805</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140017090','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140017090"><span id="translatedtitle">Influence of <span class="hlt">Observed</span> Diurnal Cycles of Aerosol Optical Depth on Aerosol <span class="hlt">Direct</span> Radiative Effect</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Arola, A.; Eck, T. F.; Huttunen, J.; Lehtinen, K. E. J.; Lindfors, A. V.; Myhre, G.; Smirinov, A.; Tripathi, S. N.; Yu, H.</p> <p>2013-01-01</p> <p>The diurnal variability of aerosol optical depth (AOD) can be significant, depending on location and dominant aerosol type. However, these diurnal cycles have rarely been taken into account in measurement-based estimates of aerosol <span class="hlt">direct</span> radiative forcing (ADRF) or aerosol <span class="hlt">direct</span> radiative effect (ADRE). The objective of our study was to estimate the influence of diurnal aerosol variability at the top of the atmosphere ADRE estimates. By including all the possible AERONET sites, we wanted to assess the influence on global ADRE estimates. While focusing also in more detail on some selected sites of strongest impact, our goal was to also see the possible impact regionally.We calculated ADRE with different assumptions about the daily AOD variability: taking the <span class="hlt">observed</span> daily AOD cycle into account and assuming diurnally constant AOD. Moreover, we estimated the corresponding differences in ADREs, if the single AOD value for the daily mean was taken from the the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra or Aqua overpass times, instead of accounting for the true <span class="hlt">observed</span> daily variability. The mean impact of diurnal AOD variability on 24 h ADRE estimates, averaged over all AERONET sites, was rather small and it was relatively small even for the cases when AOD was chosen to correspond to the Terra or Aqua overpass time. This was true on average over all AERONET sites, while clearly there can be much stronger impact in individual sites. Examples of some selected sites demonstrated that the strongest <span class="hlt">observed</span> AOD variability (the strongest morning afternoon contrast) does not typically result in a significant impact on 24 h ADRE. In those cases, the morning and afternoon AOD patterns are opposite and thus the impact on 24 h ADRE, when integrated over all solar zenith angles, is reduced. The most significant effect on daily ADRE was induced by AOD cycles with either maximum or minimum AOD close to local noon. In these cases, the impact on 24 h ADRE was typically around 0.1-0.2W/sq m (both positive and negative) in absolute values, 5-10% in relative ones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26309772','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26309772"><span id="translatedtitle">Carboxylic monolayer formation for <span class="hlt">observation</span> of intracellular structures in HeLa cells with <span class="hlt">direct</span> electron beam excitation-assisted fluorescence microscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Masuda, Yuriko; Nawa, Yasunori; Inami, Wataru; Kawata, Yoshimasa</p> <p>2015-08-01</p> <p>Intracellular structures of HeLa cells are <span class="hlt">observed</span> using a <span class="hlt">direct</span> electron beam excitation-assisted fluorescence (D-EXA) microscope. In this microscope, a silicon nitride membrane is used as a culture plate, which typically has a low biocompatibility between the sample and the silicon nitride surface to prevent the HeLa cells from adhering strongly to the surface. In this work, the surface of silicon nitride is modified to <span class="hlt">allow</span> strong cell attachment, which enables high-resolution <span class="hlt">observation</span> of intracellular structures and an increased signal-to-noise ratio. In addition, the penetration depth of the electron beam is evaluated using Monte Carlo simulations. We can conclude from the results of the <span class="hlt">observations</span> and simulations that the surface modification technique is promising for the <span class="hlt">observation</span> of intracellular structures using the D-EXA microscope. PMID:26309772</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4541536','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4541536"><span id="translatedtitle">Carboxylic monolayer formation for <span class="hlt">observation</span> of intracellular structures in HeLa cells with <span class="hlt">direct</span> electron beam excitation-assisted fluorescence microscopy</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Masuda, Yuriko; Nawa, Yasunori; Inami, Wataru; Kawata, Yoshimasa</p> <p>2015-01-01</p> <p>Intracellular structures of HeLa cells are <span class="hlt">observed</span> using a <span class="hlt">direct</span> electron beam excitation-assisted fluorescence (D-EXA) microscope. In this microscope, a silicon nitride membrane is used as a culture plate, which typically has a low biocompatibility between the sample and the silicon nitride surface to prevent the HeLa cells from adhering strongly to the surface. In this work, the surface of silicon nitride is modified to <span class="hlt">allow</span> strong cell attachment, which enables high-resolution <span class="hlt">observation</span> of intracellular structures and an increased signal-to-noise ratio. In addition, the penetration depth of the electron beam is evaluated using Monte Carlo simulations. We can conclude from the results of the <span class="hlt">observations</span> and simulations that the surface modification technique is promising for the <span class="hlt">observation</span> of intracellular structures using the D-EXA microscope. PMID:26309772</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1855374','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1855374"><span id="translatedtitle">An instrument for <span class="hlt">direct</span> <span class="hlt">observations</span> of seismic and normal-mode rotational oscillations of the Earth</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cowsik, R.</p> <p>2007-01-01</p> <p>The rotations around the vertical axis associated with the normal mode oscillations of the Earth and those induced by the seismic and other disturbances have been very difficult to <span class="hlt">observe</span> <span class="hlt">directly</span>. Such <span class="hlt">observations</span> will provide additional information for 3D modeling of the Earth and for understanding earthquakes and other underground explosions. In this paper, we describe the design of an instrument capable of measuring the rotational motions associated with the seismic oscillations of the Earth, including the lowest frequency normal mode at ? ? 3.7 × 10?4 Hz. The instrument consists of a torsion balance with a natural frequency of ?0 ? 1.6 × 10?4 Hz, which is <span class="hlt">observed</span> by an autocollimating optical lever of high angular resolution and dynamic range. Thermal noise limits the sensitivity of the apparatus to amplitudes of ? 1.5 × 10?9 rad at the lowest frequency normal mode and the sensitivity improves as ??3/2 with increasing frequency. Further improvements in sensitivity by about two orders of magnitude may be achieved by operating the balance at cryogenic temperatures. Alternatively, the instrument can be made more robust with a reduced sensitivity by increasing ?0 to ?10?2 Hz. This instrument thus complements the ongoing effort by Igel and others to study rotational motions using ring laser gyroscopes and constitutes a positive response to the clarion call for developments in rotation seismology by Igel, Lee, and Todorovska [H. Igel, W.H.K. Lee and M.I. Todorovska, AGU Fall Meeting 2006, Rotational Seismology Sessions: S22A,S23B, Inauguration of the International Working Group on Rotational Seismology (IWGoRS)]. PMID:17438268</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17438268','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17438268"><span id="translatedtitle">An instrument for <span class="hlt">direct</span> <span class="hlt">observations</span> of seismic and normal-mode rotational oscillations of the Earth.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cowsik, R</p> <p>2007-04-24</p> <p>The rotations around the vertical axis associated with the normal mode oscillations of the Earth and those induced by the seismic and other disturbances have been very difficult to <span class="hlt">observe</span> <span class="hlt">directly</span>. Such <span class="hlt">observations</span> will provide additional information for 3D modeling of the Earth and for understanding earthquakes and other underground explosions. In this paper, we describe the design of an instrument capable of measuring the rotational motions associated with the seismic oscillations of the Earth, including the lowest frequency normal mode at nu approximately 3.7 x 10(-4) Hz. The instrument consists of a torsion balance with a natural frequency of nu(0) approximately 1.6 x 10(-4) Hz, which is <span class="hlt">observed</span> by an autocollimating optical lever of high angular resolution and dynamic range. Thermal noise limits the sensitivity of the apparatus to amplitudes of approximately 1.5 x 10(-9) rad at the lowest frequency normal mode and the sensitivity improves as nu(-3/2) with increasing frequency. Further improvements in sensitivity by about two orders of magnitude may be achieved by operating the balance at cryogenic temperatures. Alternatively, the instrument can be made more robust with a reduced sensitivity by increasing nu(0) to approximately 10(-2) Hz. This instrument thus complements the ongoing effort by Igel and others to study rotational motions using ring laser gyroscopes and constitutes a positive response to the clarion call for developments in rotation seismology by Igel, Lee, and Todorovska [H. Igel, W.H.K. Lee and M.I. Todorovska, AGU Fall Meeting 2006, Rotational Seismology Sessions: S22A,S23B, Inauguration of the International Working Group on Rotational Seismology (IWGoRS)]. PMID:17438268</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://mnspruce.ornl.gov/system/files/Li-7500_Calibration_procedure_20150601.pdf','EPRINT'); return false;" href="http://mnspruce.ornl.gov/system/files/Li-7500_Calibration_procedure_20150601.pdf"><span id="translatedtitle">Page 1 of 4 3) <span class="hlt">Observe</span> the H2O dewpoint in the main window and <span class="hlt">allow</span> it to stabilize (15-20 mins or more). Once stable, click</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>Set Up 1) 2) 3) 4) 5) 6) END Page 1 of 4 3) <span class="hlt">Observe</span> the H2O dewpoint in the main window and <span class="hlt">allow</span> and note the Sw value. Sw should typically be between 0.9-1.1. Zero H2O 1) Flow CO2-Free air through is stable. 3) Click Zero H2O to set the H2O Zero. New Zwo value should be between 0.65-0.85. Span CO2 1</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2002_grl_2041.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2002_grl_2041.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> comparison of pulsating aurora <span class="hlt">observed</span> simultaneously by the FAST satellite and from the ground at Syowa</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Carlson, Charles W.</p> <p></p> <p><span class="hlt">Direct</span> comparison of pulsating aurora <span class="hlt">observed</span> simultaneously by the FAST satellite and from September 2002; published 15 November 2002. [1] We have made a <span class="hlt">direct</span> comparison of a pulsating aurora: a poleward moving pulsation and a standing mode pulsation, each with a period of $5 sec. The aurora occurs</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://csg.csail.mit.edu/people/devadas/pubs/iccad2000.ps','EPRINT'); return false;" href="http://csg.csail.mit.edu/people/devadas/pubs/iccad2000.ps"><span id="translatedtitle"><span class="hlt">Observability</span> Analysis of Embedded Software for Coverage<span class="hlt">Directed</span> Validation Jose C. Costa Srinivas Devadas Jose C. Monteiro</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Devadas, Srinivas</p> <p></p> <p>­ nificantly more accurate assessment of design verification coverage than statement coverage. Existing<span class="hlt">Observability</span> Analysis of Embedded Software for Coverage­<span class="hlt">Directed</span> Validation Josâ??e C. Costa (HDL) is simulated with the ap­ propriate input vectors. In coverage­<span class="hlt">directed</span> validation, coverage</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1184944','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1184944"><span id="translatedtitle">In Situ <span class="hlt">Observation</span> of <span class="hlt">Directed</span> Nanoparticle Aggregation During the Synthesis of Ordered Nanoporous Metal in Soft Templates</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Parent, Lucas R.; Robinson, David B.; Cappillino, Patrick J.; Hartnett, Ryan J.; Abellan Baeza, Patricia; Evans, James E.; Browning, Nigel D.; Arslan, Ilke</p> <p>2014-02-11</p> <p>The prevalent approach to developing new nanomaterials is a trial and error process of iteratively altering synthesis procedures and then characterizing the resulting nanostructures. This is fundamentally limited in that the growth processes that occur during synthesis can only be inferred from the final synthetic structure. <span class="hlt">Directly</span> <span class="hlt">observing</span> real-time nanomaterial growth provides unprecedented insight into the relationship between synthesis conditions and product evolution, and facilitates a mechanistic approach to nanomaterial development. Here we use in situ liquid stage scanning transmission electron microscopy to <span class="hlt">observe</span> the growth of mesoporous palladium in a solvated block copolymer (BCP) template under various synthesis conditions, and ultimately determine a refined synthesis procedure that yields ordered pores. We find that at low organic solvent (tetrahydrofuran, THF) content, the BCP assembles into a rigid, cylindrical micelle array with a high degree of short-range order, but poor long-range order. Upon slowing the THF evaporation rate using a solvent-vapor anneal step, the long-range order is greatly improved. The electron beam induces nucleation of small particles in the aqueous phase around the micelles. The small particles then flocculate and grow into denser structures that surround the micelles, forming an ordered mesoporous structure. The microscope <span class="hlt">observations</span> revealed that template disorder can be addressed prior to reaction, and is not invariably induced by the growth process itself, <span class="hlt">allowing</span> us to more quickly optimize the synthetic method. This work was conducted in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by DOE’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. The Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy under contract DE-AC05-76RL01830. This research was funded in part by: the Presidential Early Career Award for Scientist and Engineers for I.A., the University of California Academic Senate and the University of California Laboratory fee research grant, the Laboratory-<span class="hlt">Directed</span> Research and Development program at Sandia National Laboratories, and the Chemical Imaging Initiative at Pacific Northwest National Laboratory. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015A%26A...581A.100C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015A%26A...581A.100C"><span id="translatedtitle">Low frequency radio <span class="hlt">observations</span> of bi-<span class="hlt">directional</span> electron beams in the solar corona</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carley, Eoin P.; Reid, Hamish; Vilmer, Nicole; Gallagher, Peter T.</p> <p>2015-09-01</p> <p>The radio signature of a shock travelling through the solar corona is known as a type II solar radio burst. In rare cases these bursts can exhibit a fine structure known as "herringbones", which are a <span class="hlt">direct</span> indicator of particle acceleration occurring at the shock front. However, few studies have been performed on herringbones and the details of the underlying particle acceleration processes are unknown. Here, we use an image processing technique known as the Hough transform to statistically analyse the herringbone fine structure in a radio burst at ~20-90 MHz <span class="hlt">observed</span> from the Rosse Solar-Terrestrial Observatory on 2011 September 22. We identify 188 individual bursts which are signatures of bi-<span class="hlt">directional</span> electron beams continuously accelerated to speeds of 0.16-0.10+0.11 c. This occurs at a shock acceleration site initially at a constant altitude of ~0.6 R? in the corona, followed by a shift to ~0.5 R?. The anti-sunward beams travel a distance of 170-97+174 Mm (and possibly further) away from the acceleration site, while those travelling toward the Sun come to a stop sooner, reaching a smaller distance of 112-76+84 Mm. We show that the stopping distance for the sunward beams may depend on the total number density and the velocity of the beam. Our study concludes that a detailed statistical analysis of herringbone fine structure can provide information on the physical properties of the corona which lead to these relatively rare radio bursts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1309.3543v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1309.3543v1"><span id="translatedtitle">Constraining nova <span class="hlt">observables</span>: <span class="hlt">direct</span> measurements of resonance strengths in 33S(p,?)34Cl</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>J. Fallis; A. Parikh; P. F. Bertone; S. Bishop; L. Buchmann; A. A. Chen; G. Christian; J. A. Clark; J. M. D'Auria; B. Davids; C. M. Deibel; B. R. Fulton; U. Greife; B. Guo; U. Hager; C. Herlitzius; D. A. Hutcheon; J. José; A. M. Laird; E. T. Li; Z. H. Li; G. Lian; W. P. Liu; L. Martin; K. Nelson; D. Ottewell; P. D. Parker; S. Reeve; A. Rojas; C. Ruiz; K. Setoodehnia; S. Sjue; C. Vockenhuber; Y. B. Wang; C. Wrede</p> <p>2013-09-13</p> <p>The 33S(p,\\gamma)34Cl reaction is important for constraining predictions of certain isotopic abundances in oxygen-neon novae. Models currently predict as much as 150 times the solar abundance of 33S in oxygen-neon nova ejecta. This overproduction factor may, however, vary by orders of magnitude due to uncertainties in the 33S(p,\\gamma)34Cl reaction rate at nova peak temperatures. Depending on this rate, 33S could potentially be used as a diagnostic tool for classifying certain types of presolar grains. Better knowledge of the 33S(p,\\gamma)34Cl rate would also aid in interpreting nova <span class="hlt">observations</span> over the S-Ca mass region and contribute to the firm establishment of the maximum endpoint of nova nucleosynthesis. Additionally, the total S elemental abundance which is affected by this reaction has been proposed as a thermometer to study the peak temperatures of novae. Previously, the 33S(p,\\gamma)34Cl reaction rate had only been studied <span class="hlt">directly</span> down to resonance energies of 432 keV. However, for nova peak temperatures of 0.2-0.4 GK there are 7 known states in 34Cl both below the 432 keV resonance and within the Gamow window that could play a dominant role. <span class="hlt">Direct</span> measurements of the resonance strengths of these states were performed using the DRAGON recoil separator at TRIUMF. Additionally two new states within this energy region are reported. Several hydrodynamic simulations have been performed, using all available experimental information for the 33S(p,\\gamma)34Cl rate, to explore the impact of the remaining uncertainty in this rate on nucleosynthesis in nova explosions. These calculations give a range of ~ 20-150 for the expected 33S overproduction factor, and a range of ~ 100-450 for the 32S/33S ratio expected in ONe novae.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25491879','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25491879"><span id="translatedtitle">Melt electrospinning of poly(?-caprolactone) scaffolds: phenomenological <span class="hlt">observations</span> associated with collection and <span class="hlt">direct</span> writing.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brown, Toby D; Edin, Fredrik; Detta, Nicola; Skelton, Anthony D; Hutmacher, Dietmar W; Dalton, Paul D</p> <p>2014-12-01</p> <p>Melt electrospinning and its additive manufacturing analogue, melt electrospinning writing (MEW), are two processes which can produce porous materials for applications where solvent toxicity and accumulation in solution electrospinning are problematic. This study explores the melt electrospinning of poly(?-caprolactone) (PCL) scaffolds, specifically for applications in tissue engineering. The research described here aims to inform researchers interested in melt electrospinning about technical aspects of the process. This includes rapid fiber characterization using glass microscope slides, <span class="hlt">allowing</span> influential processing parameters on fiber morphology to be assessed, as well as <span class="hlt">observed</span> fiber collection phenomena on different collector substrates. The distribution and alignment of melt electrospun PCL fibers can be controlled to a certain degree using patterned collectors to create large numbers of scaffolds with shaped macroporous architectures. However, the buildup of residual charge in the collected fibers limits the achievable thickness of the porous template through such scaffolds. One challenge identified for MEW is the ability to control charge buildup so that fibers can be placed accurately in close proximity, and in many centimeter heights. The scale and size of scaffolds produced using MEW, however, indicate that this emerging process will fill a technological niche in biofabrication. PMID:25491879</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22036703','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22036703"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of heat dissipation in individual suspended carbon nanotubes using a two-laser technique</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hsu, I-Kai; Hung, Wei-Hsuan; Pettes, Michael T.; Shi Li; Aykol, Mehmet; Theiss, Jesse; Cronin, Stephen B.; Chang, Chia-Chi</p> <p>2011-08-15</p> <p>A two-laser technique is used to investigate heat spreading along individual single walled carbon nanotube (SWCNT) bundles in vacuum and air environments. A 532 nm laser focused on the center of a suspended SWCNT bundle is used as a local heat source, and a 633 nm laser is used to measure the spatial temperature profile along the SWCNT bundle by monitoring the G band downshifts in the Raman spectra. A constant temperature gradient is <span class="hlt">observed</span> when the SWCNT bundle is irradiated in vacuum, giving <span class="hlt">direct</span> evidence of diffusive transport of the phonons probed by the Raman laser. In air, however, we <span class="hlt">observe</span> an exponentially decaying temperature profile with a decay length of about 7 {mu}m, due to heat dissipation from the SWCNT bundle to the surrounding gas molecules. The thermal conductivity of the suspended carbon nanotube (CNT) is determined from its electrical heating temperature profile as measured in vacuum and the nanotube bundle diameter measured via transmission electron microscopy. Based on the exponential decay curves measured in three different CNTs in air, the heat transfer coefficient between the SWCNTs and the surrounding air molecules is found to range from 1.5 x 10{sup 3} to 7.9 x 10{sup 4} W/m{sup 2} K, which is smaller than the 1 x 10{sup 5} W/m{sup 2} K thermal boundary conductance value calculated using the kinetic theory of gases. This measurement is insensitive to the thermal contact resistance, as no temperature drops occur at the ends of the nanotube. It is also insensitive to errors in the calibration of the G band temperature coefficient. The optical absorption is also obtained from these results and is on the order of 10{sup -5}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1136584','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1136584"><span id="translatedtitle">Quantifying Aerosol <span class="hlt">Direct</span> Effects from Broadband Irradiance and Spectral Aerosol Optical Depth <span class="hlt">Observations</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Creekmore, Torreon N.; Joseph, Everette; Long, Charles N.; Li, Siwei</p> <p>2014-05-16</p> <p>We outline a methodology using broadband and spectral irradiances to quantify aerosol <span class="hlt">direct</span> effects on the surface diffuse shortwave (SW) irradiance. Best Estimate Flux data span a 13 year timeframe at the Department of Energy Atmospheric Radiation Measurement Program’s Southern Great Plains (SGP) site. Screened clear-sky irradiances and aerosol optical depth (AOD), for solar zenith angles ? 65°, are used to estimate clear-sky diffuse irradiances. We validate against detected clear-sky <span class="hlt">observations</span> from SGP’s Basic Radiation System (BRS). BRS diffuse irradiances were in accordance with estimates, producing a root-mean-square error and mean bias errors of 4.0 W/m2 and -1.4 W/m2, respectively. Absolute differences show 99% of estimates within ±10 W/m2 (10%) of the mean BRS <span class="hlt">observations</span>. Clear-sky diffuse estimates are used to derive quantitative estimates of aerosol radiative effects, represented as the aerosol diffuse irradiance (ADI). ADI is the contribution of diffuse SW to global SW, attributable to scattering of atmospheric transmission by natural plus anthropogenic aerosols. Estimated slope for the ADI as a function of AOD indicates an increase of ~22 W/m2 in diffuse SW for every 0.1 increase in AOD. Such significant increases in the diffuse fraction could possibly increase photosynthesis. Annual mean ADI is 28.2 W/m2, and heavy aerosol loading at SGP provides up to a maximum increase of 120 W/m2 in diffuse SW over background conditions. With regard to seasonal variation, the mean diffuse forcings are 17.2, 33.3, 39.0, and 23.6 W/m2 for winter, spring, summer, and fall, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.chm.bris.ac.uk/pt/diamond/pdf/apl104-171907.pdf','EPRINT'); return false;" href="http://www.chm.bris.ac.uk/pt/diamond/pdf/apl104-171907.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of electron emission from the grain boundaries of chemical vapour deposition diamond films by tunneling atomic force microscopy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Bristol, University of</p> <p></p> <p><span class="hlt">observation</span> of the emission sites over a large area of polycrystalline diamond using tunneling atomic force<span class="hlt">Direct</span> <span class="hlt">observation</span> of electron emission from the grain boundaries of chemical vapour deposition for polycrystalline low pressure chemical vapour deposition ZnO:B films J. Appl. Phys. 113, 123104 (2013); 10</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApSS..315..212Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApSS..315..212Y"><span id="translatedtitle">Investigation of droplet jumping on superhydrophobic coatings during dew condensation by the <span class="hlt">observation</span> from two <span class="hlt">directions</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yanagisawa, Kosuke; Sakai, Munetoshi; Isobe, Toshihiro; Matsushita, Sachiko; Nakajima, Akira</p> <p>2014-10-01</p> <p>Superhydrophobic coatings with nanoscale random roughness structure were prepared onto a Si substrate using boehmite (AlOOH) particles and hydrophobic silanes. The samples were cooled by a Peltier cooling element. Then spontaneous jumping behavior of the water droplets that had condensed on the coatings was <span class="hlt">observed</span> from two <span class="hlt">directions</span> (top-view and side-view) using high-speed camera systems. Spontaneous jumping of water droplets occurred subsequent to the coalescence of more than two water droplets, deformation, and shape recovery. Small droplets exhibited high initial jumping velocity, which decreased concomitantly with increasing difference in droplet size before coalescence. The actual jumping velocity was lower than the theoretical one, suggesting the existence of energy dissipation. When the sample was declined at 30°, the jumping frequency of water droplets fluctuated against the cooling time with repetition of the increasing-decreasing cycle, and sustained a certain value. The water droplet jumping height was increased remarkably under an external electric field. The droplet possessed positive charge. Coulombic force was expected to contribute to this phenomenon.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..MARF42006K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..MARF42006K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of the End-to-End Distance of Chains in a Polymer Langmuir Monolayer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kumaki, Jiro; Honma, Fumiki</p> <p>2015-03-01</p> <p>Polymer chain packing in two-dimensional (2D) condense state is still not well understood. <span class="hlt">Direct</span> <span class="hlt">observation</span> of the chain packing in a monolayer should be the best way to understand this, however, it is still difficult even using atomic force microscopy (AFM) except for extraordinarily thick polymers. In this study, we successfully evaluate the end-to-end distance of the chains in a Langmuir-Blodgett monolayer composed of a conventional polymer by AFM. We successfully solubilized a small amount of a polystyrene-b-poly(methyl methacrylate)-b-polystyrene (PS-b-PMMA-b-PS) triblock copolymer in a PMMA Langmuir monolayer with the PS blocks being condensed as single-PS-block particles which could be used as a probe of the position of the chain ends. The evaluated end-to-end distance was 2.5 times longer than that of the 2D ideal chain, indicating the chains in the 2D monolayer are not strongly segregated but interpenetrates into other chains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26056735','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26056735"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of a Carbon Filament in Water-Resistant Organic Memory.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Byung-Hyun; Bae, Hagyoul; Seong, Hyejeong; Lee, Dong-Il; Park, Hongkeun; Choi, Young Joo; Im, Sung-Gap; Kim, Sang Ouk; Choi, Yang-Kyu</p> <p>2015-07-28</p> <p>The memory for the Internet of Things (IoT) requires versatile characteristics such as flexibility, wearability, and stability in outdoor environments. Resistive random access memory (RRAM) to harness a simple structure and organic material with good flexibility can be an attractive candidate for IoT memory. However, its solution-oriented process and unclear switching mechanism are critical problems. Here we demonstrate iCVD polymer-intercalated RRAM (i-RRAM). i-RRAM exhibits robust flexibility and versatile wearability on any substrate. Stable operation of i-RRAM, even in water, is demonstrated, which is the first experimental presentation of water-resistant organic memory without any waterproof protection package. Moreover, the <span class="hlt">direct</span> <span class="hlt">observation</span> of a carbon filament is also reported for the first time using transmission electron microscopy, which puts an end to the controversy surrounding the switching mechanism. Therefore, reproducibility is feasible through comprehensive modeling. Furthermore, a carbon filament is superior to a metal filament in terms of the design window and selection of the electrode material. These results suggest an alternative to solve the critical issues of organic RRAM and an optimized memory type suitable for the IoT era. PMID:26056735</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3361450','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3361450"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of turbulent magnetic fields in hot, dense laser produced plasmas</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mondal, Sudipta; Narayanan, V.; Ding, Wen Jun; Lad, Amit D.; Hao, Biao; Ahmad, Saima; Wang, Wei Min; Sheng, Zheng Ming; Sengupta, Sudip; Kaw, Predhiman; Das, Amita; Kumar, G. Ravindra</p> <p>2012-01-01</p> <p>Turbulence in fluids is a ubiquitous, fascinating, and complex natural phenomenon that is not yet fully understood. Unraveling turbulence in high density, high temperature plasmas is an even bigger challenge because of the importance of electromagnetic forces and the typically violent environments. Fascinating and novel behavior of hot dense matter has so far been only indirectly inferred because of the enormous difficulties of making <span class="hlt">observations</span> on such matter. Here, we present <span class="hlt">direct</span> evidence of turbulence in giant magnetic fields created in an overdense, hot plasma by relativistic intensity (1018W/cm2) femtosecond laser pulses. We have obtained magneto-optic polarigrams at femtosecond time intervals, simultaneously with micrometer spatial resolution. The spatial profiles of the magnetic field show randomness and their k spectra exhibit a power law along with certain well defined peaks at scales shorter than skin depth. Detailed two-dimensional particle-in-cell simulations delineate the underlying interaction between forward currents of relativistic energy “hot” electrons created by the laser pulse and “cold” return currents of thermal electrons induced in the target. Our results are not only fundamentally interesting but should also arouse interest on the role of magnetic turbulence induced resistivity in the context of fast ignition of laser fusion, and the possibility of experimentally simulating such structures with respect to the sun and other stellar environments. PMID:22566660</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...812L...7V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...812L...7V"><span id="translatedtitle">A Far-infrared <span class="hlt">Observational</span> Test of the <span class="hlt">Directional</span> Dependence in Radiative Grain Alignment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vaillancourt, John E.; Andersson, B.-G.</p> <p>2015-10-01</p> <p>The alignment of interstellar dust grains with magnetic fields provides a key method for measuring the strength and morphology of the fields. In turn, this provides a means to study the role of magnetic fields from diffuse gas to dense star-forming regions. The physical mechanism for aligning the grains has been a long-term subject of study and debate. The theory of radiative torques, in which an anisotropic radiation field imparts sufficient torques to align the grains while simultaneously spinning them to high rotational velocities, has passed a number of <span class="hlt">observational</span> tests. Here we use archival polarization data in dense regions of the Orion molecular cloud (OMC-1) at 100, 350, and 850 ?m to test the prediction that the alignment efficiency is dependent upon the relative orientations of the magnetic field and radiation anisotropy. We find that the expected polarization signal, with a 180-degree period, exists at all wavelengths out to radii of 1.5 arcmin centered on the Becklin-Neugebauer Kleinmann-Low (BNKL) object in OMC-1. The probabilities that these signals would occur due to random noise are low (?1%), and are lowest toward BNKL compared to the rest of the cloud. Additionally, the relative magnetic field to radiation anisotropy <span class="hlt">directions</span> accord with theoretical predictions in that they agree to better than 15° at 100 ?m and 4° at 350 ?m.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.H31D1192B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.H31D1192B"><span id="translatedtitle"><span class="hlt">Direct</span> Pore-Level <span class="hlt">Observation</span> of Permeability Increase by Seismic Waves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beresnev, I. A.; Gaul, W.; Vigil, D.</p> <p>2011-12-01</p> <p>Increases in permeability of natural reservoirs and aquifers by passing seismic waves have been well documented. If the physical causes of this phenomenon can be understood, technological applications would be possible for controlling the flow in hydrologic systems or enhancing production from oil reservoirs. The explanation of the dynamically increased mobility of underground fluids lies at the pore level. The natural fluids can be viewed as two-phase systems, composed of water as the wetting phase and of dispersed non-wetting globules of gas or organic fluids flowing through tortuous constricted channels. Capillary forces prevent the free motion of the suspended non-wetting droplets, which tend to become immobilized in capillary constrictions. The capillary entrapment significantly reduces macroscopic permeability. In a controlled experiment with a constricted capillary channel, we immobilize the suspended ganglia and test the model of capillary entrapment: it agrees precisely with the experiment. We then demonstrate by <span class="hlt">direct</span> optical pore-level <span class="hlt">observation</span> that the vibrations applied to the wall of the channel liberate the trapped ganglia if a certain critical acceleration is reached. When the droplet begins to progressively advance, the permeability is restored. The mobilizing acceleration in the elastic wave, needed to "unplug" an immobile flow, is theoretically predicted within a factor of 1-5 of the experimental value. Overcoming the capillary entrapment in porous channels is hypothesized to be one of the principal mechanisms by which natural permeabilities are enhanced by the passage of seismic waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011GeoRL..3820302B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011GeoRL..3820302B"><span id="translatedtitle"><span class="hlt">Direct</span> pore-level <span class="hlt">observation</span> of permeability increase in two-phase flow by shaking</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beresnev, Igor; Gaul, William; Vigil, R. Dennis</p> <p>2011-10-01</p> <p>Increases in permeability of natural reservoirs and aquifers by passing seismic waves have been well documented. If the physical causes of this phenomenon can be understood, technological applications would be possible for controlling the flow in hydrologic systems or enhancing production from oil reservoirs. The explanation of the dynamically increased mobility of underground fluids must lie at the pore level. The natural fluids can be viewed as two-phase systems, composed of water as the wetting phase and of dispersed non-wetting globules of gas or organic fluids, flowing through tortuous constricted channels. Capillary forces prevent free motion of the suspended non-wetting droplets, which tend to become immobilized in capillary constrictions. The capillary entrapment significantly reduces macroscopic permeability. In a controlled experiment with a constricted capillary channel, we immobilize the suspended ganglia and test the model of capillary entrapment: it agrees precisely with the experiment. We then demonstrate by <span class="hlt">direct</span> optical pore-level <span class="hlt">observation</span> that the vibrations applied to the wall of the channel liberate the trapped ganglia if a predictable critical acceleration is reached. When the droplet begins to progressively advance, the permeability is restored. The mobilizing acceleration in the elastic wave, needed to “unplug” an immobile flow, is theoretically calculated within a factor of 1-5 of the experimental value. Overcoming the capillary entrapment in porous channels is hypothesized to be one of the principal pore-scale mechanisms by which natural permeabilities are enhanced by the passage of elastic waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22566660','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22566660"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of turbulent magnetic fields in hot, dense laser produced plasmas.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mondal, Sudipta; Narayanan, V; Ding, Wen Jun; Lad, Amit D; Hao, Biao; Ahmad, Saima; Wang, Wei Min; Sheng, Zheng Ming; Sengupta, Sudip; Kaw, Predhiman; Das, Amita; Kumar, G Ravindra</p> <p>2012-05-22</p> <p>Turbulence in fluids is a ubiquitous, fascinating, and complex natural phenomenon that is not yet fully understood. Unraveling turbulence in high density, high temperature plasmas is an even bigger challenge because of the importance of electromagnetic forces and the typically violent environments. Fascinating and novel behavior of hot dense matter has so far been only indirectly inferred because of the enormous difficulties of making <span class="hlt">observations</span> on such matter. Here, we present <span class="hlt">direct</span> evidence of turbulence in giant magnetic fields created in an overdense, hot plasma by relativistic intensity (10(18) W/cm(2)) femtosecond laser pulses. We have obtained magneto-optic polarigrams at femtosecond time intervals, simultaneously with micrometer spatial resolution. The spatial profiles of the magnetic field show randomness and their k spectra exhibit a power law along with certain well defined peaks at scales shorter than skin depth. Detailed two-dimensional particle-in-cell simulations delineate the underlying interaction between forward currents of relativistic energy "hot" electrons created by the laser pulse and "cold" return currents of thermal electrons induced in the target. Our results are not only fundamentally interesting but should also arouse interest on the role of magnetic turbulence induced resistivity in the context of fast ignition of laser fusion, and the possibility of experimentally simulating such structures with respect to the sun and other stellar environments. PMID:22566660</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2560681','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2560681"><span id="translatedtitle"><span class="hlt">Directly</span> <span class="hlt">observed</span> treatment, short-course strategy and multidrug-resistant tuberculosis: are any modifications required?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bastian, I.; Rigouts, L.; Van Deun, A.; Portaels, F.</p> <p>2000-01-01</p> <p>Multidrug-resistant tuberculosis (MDRTB) should be defined as tuberculosis with resistance to at least isoniazid and rifampicin because these drugs are the cornerstone of short-course chemotherapy, and combined isoniazid and rifampicin resistance requires prolonged treatment with second-line agents. Short-course chemotherapy is a key ingredient in the tuberculosis control strategy known as <span class="hlt">directly</span> <span class="hlt">observed</span> treatment, short-course (DOTS). For populations in which multidrug-resistant tuberculosis is endemic, the outcome of the standard short-course chemotherapy regimen remains uncertain. Unacceptable failure rates have been reported and resistance to additional agents may be induced. As a consequence there have been calls for well-functioning DOTS programmes to provide additional services in areas with high rates of multidrug-resistant tuberculosis. These "DOTS-plus for MDRTB programmes" may need to modify all five elements of the DOTS strategy: the treatment may need to be individualized rather than standardized; laboratory services may need to provide facilities for on-site culture and antibiotic susceptibility testing; reliable supplies of a wide range of expensive second-line agents would have to be supplied; operational studies would be required to determine the indications for and format of the expanded programmes; financial and technical support from international organizations and Western governments would be needed in addition to that obtained from local governments. PMID:10743297</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940020144','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940020144"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of crystal growth from solution using optical investigation of a growing crystal face</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lal, Ravindra</p> <p>1994-01-01</p> <p>The first technical report for the period 1 Jan. 1993 till 31 Dec. 1993 for the research entitled, '<span class="hlt">Direct</span> <span class="hlt">observation</span> of crystal growth from solution using Optical Investigation of a growing crystal Face' is presented. The work on the project did not start till 1 June 1993 due to the non-availability of the required personnel. The progress of the work during the period 1 June 1993 till the end of 1993 is described. Significant progress was made for testing various optical diagnostic techniques for monitoring crystal solution. Some of the techniques that are being tested are: heterodyne detection technique, in which changes in phase are measured as a interferometric function of time/crystal growth; a conventional technique, in which a fringe brightness is measured as a function of crystal growth/time; and a Mach-Zehnder interferometric technique in which a fringe brightness is measured as a function of time to obtain information on concentration changes. During the second year it will be decided to incorporate the best interferometric technique along with the ellipsometric technique, to obtain real time in-situ growth rate measurements. A laboratory mock-up of the first two techniques were made and tested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4464364','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4464364"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of solid-state reversed transformation from crystals to quasicrystals in a Mg alloy</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Jian-Fang; Yang, Zhi-Qing; Ye, Heng-Qiang</p> <p>2015-01-01</p> <p>Phase transformation of quasicrystals is of interest in various fields of science and technology. Interestingly, we <span class="hlt">directly</span> <span class="hlt">observed</span> unexpected solid-state epitaxial nucleation and growth of Zn 6 Mg 3 Y icosahedral quasicrystals in a Mg alloy at about 573?K which is about 300?K below the melting point of Zn 6 Mg 3 Y, in contrast to formation of quasicrystals through solidification that was usually found in many alloys. Maximizing local packing density of atoms associated with segregation of Y and Zn in Mg adjacent to Mg/Zn 3 MgY interfaces triggered atomic rearrangement in Mg to form icosahedra coupled epitaxially with surface distorted icosahedra of Zn 3 MgY, which plays a critical role in the nucleation of icosahedral clusters. A local Zn:Mg:Y ratio close to 6:3:1, corresponding to a valence electron concentration of about 2.15, should have been reached to trigger the formation of quasicrystals at Mg/Zn 3 MgY interfaces. The solid-state icosahedral ordering in crystals opens a new window for growing quasicrystals and understanding their atomic origin mechanisms. Epitaxial growth of quasicrystals onto crystals can modify the surface/interface structures and properties of crystalline materials. PMID:26066096</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26462749','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26462749"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of epitaxial organic film growth: temperature-dependent growth mechanisms and metastability.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marchetto, Helder; Schmidt, Thomas; Groh, Ullrich; Maier, Florian C; Lévesque, Pierre L; Fink, Rainer H; Freund, Hans-Joachim; Umbach, Eberhard</p> <p>2015-10-28</p> <p>The growth of the first ten layers of organic thin films on a smooth metallic substrate has been investigated in real-time using the model system PTCDA on Ag(111). The complex behaviour is comprehensively studied by electron microscopy, spectroscopy and diffraction in a combined PEEM/LEEM instrument revealing several new phenomena and yielding a consistent picture of this layer growth. PTCDA grows above room temperature in a Stranski-Krastanov mode, forming three-dimensional islands on a stable bi-layer, in competition with metastable 3rd and 4th layers. Around room temperature this growth mode changes into a quasi layer-by-layer growth, while at temperatures below about 250 K a Vollmer-Weber-like behaviour is <span class="hlt">observed</span>. By means of laterally resolved soft X-ray absorption spectroscopy the orientation of all adsorbed molecules is found to be homogeneously flat lying on the surface, even during the growth process. The films grow epitaxially, showing long-range order with rotational domains. For the monolayer these domains could be <span class="hlt">directly</span> analysed, showing an average size of several micrometers extending over substrate steps. PMID:26462749</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26066096','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26066096"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of solid-state reversed transformation from crystals to quasicrystals in a Mg alloy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Jian-Fang; Yang, Zhi-Qing; Ye, Heng-Qiang</p> <p>2015-01-01</p> <p>Phase transformation of quasicrystals is of interest in various fields of science and technology. Interestingly, we <span class="hlt">directly</span> <span class="hlt">observed</span> unexpected solid-state epitaxial nucleation and growth of Zn6Mg3Y icosahedral quasicrystals in a Mg alloy at about 573?K which is about 300?K below the melting point of Zn6Mg3Y, in contrast to formation of quasicrystals through solidification that was usually found in many alloys. Maximizing local packing density of atoms associated with segregation of Y and Zn in Mg adjacent to Mg/Zn3MgY interfaces triggered atomic rearrangement in Mg to form icosahedra coupled epitaxially with surface distorted icosahedra of Zn3MgY, which plays a critical role in the nucleation of icosahedral clusters. A local Zn:Mg:Y ratio close to 6:3:1, corresponding to a valence electron concentration of about 2.15, should have been reached to trigger the formation of quasicrystals at Mg/Zn3MgY interfaces. The solid-state icosahedral ordering in crystals opens a new window for growing quasicrystals and understanding their atomic origin mechanisms. Epitaxial growth of quasicrystals onto crystals can modify the surface/interface structures and properties of crystalline materials. PMID:26066096</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3960716','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3960716"><span id="translatedtitle">Build a Better Mouse: <span class="hlt">Directly-Observed</span> Issues in Computer Use for Adults with SMI</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Black, Anne C.; Serowik, Kristin L.; Schensul, Jean J.; Bowen, Anne M.; Rosen, Marc I.</p> <p>2014-01-01</p> <p>Integrating information technology into healthcare has the potential to bring treatment to hard-to-reach people. Individuals with serious mental illness (SMI), however, may derive limited benefit from these advances in care because of lack of computer ownership and experience. To date, conclusions about the computer skills and attitudes of adults with SMI have been based primarily on self-report. In the current study, 28 psychiatric outpatients with co-occurring cocaine use were interviewed about their computer use and opinions, and 25 were then <span class="hlt">directly</span> <span class="hlt">observed</span> using task analysis and think aloud methods as they navigated a multi-component health informational website. Participants reported low rates of computer ownership and use, and negative attitudes towards computers. Self-reported computer skills were higher than demonstrated in the task analysis. However, some participants spontaneously expressed more positive attitudes and greater computer self-efficacy after navigating the website. Implications for increasing access to computer-based health information are discussed. PMID:22711454</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2659034','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2659034"><span id="translatedtitle">Attitudes to <span class="hlt">directly</span> <span class="hlt">observed</span> antiretroviral treatment in a workplace HIV care programme in South Africa</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Page?Shipp, Liesl S; Charalambous, Salome; Roux, Surita; Dias, Belinda; Sefuti, Clement; Churchyard, Gavin J; Grant, Alison D</p> <p>2007-01-01</p> <p>Objective To investigate attitudes to <span class="hlt">directly</span> <span class="hlt">observed</span> antiretroviral therapy (DOT ART) among HIV infected adults attending a workplace HIV care programme in South Africa. Methods Clients attending workplace HIV clinics in two regions were interviewed using a semi?structured questionnaire. Results 100 individuals (99% male, mean age 40.2?years) participated, 61% were already taking ART by self administration. 71% had previous tuberculosis (TB) with the majority having received DOT for TB. 65% of individuals indicated that they would not like to receive ART by DOT—the main reason given was a desire to take responsibility for their own treatment. This contrasted with 79% who thought TB treatment by DOT a good idea. On questioning about disclosure, 70% reported disclosure to their sexual partners and 21% to fellow workers. 78% of individuals indicated willingness to support someone else taking ART. Conclusion ART by DOT was not an immediately popular concept with our patients, primarily because of a desire to retain responsibility for their own treatment. More work is needed to understand what key elements of treatment support are needed to promote adherence. PMID:17567686</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17639650','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17639650"><span id="translatedtitle">Modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy for antiretroviral therapy: a primer from the field.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Goggin, Kathy; Liston, Robin J; Mitty, Jennifer Adelson</p> <p>2007-01-01</p> <p>Modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (mDOT), in which a portion of total doses of a medication regime is ingested under supervision, has demonstrated efficacy as an intervention to assist patients in maintaining adherence to complicated antiretroviral therapy (ART). Although findings are favorable, existing efficacy studies fail to provide sufficient detail to guide others who wish to implement mDOT interventions. The aim of this article is to provide a primer for practitioners and researchers who wish to implement mDOT interventions. Drawing on the experience of 10 federally funded research projects, we provide guidance on critical questions for program implementation, including: who should be targeted, length/duration/content/location/tapering of sessions, staffing, incentives, and approaches to data collection. In addition, guidance on staff training and minimum requirements for mDOT interventions is offered along with real-world examples of mDOT interventions. mDOT is feasible and easily adapted to many settings and target populations. Interventions should match the specific needs of the target population and setting and be flexible in terms of design and delivery. mDOT should be considered among the spectrum of adherence interventions. PMID:17639650</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/940565','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/940565"><span id="translatedtitle"><span class="hlt">Direct</span> real-space <span class="hlt">observation</span> of nearly stochastic behavior in magnetization reversal process on a nanoscale</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Im, M.-Y.; Kim, D.-H.; Lee, K.-D.; Fischer, P.; Shin, S.-C.</p> <p>2007-06-01</p> <p>We report a non-deterministic nature in the magnetization reversal of nanograins of CoCrPt alloy film. Magnetization reversal process of CoCrPt alloy film is investigated using high resolution soft X-ray microscopy which provides real space images with a spatial resolution of 15 nm. Domain nucleation sites mostly appear stochastically distributed within repeated hysteretic cycles, where the correlation increases as the strength of the applied magnetic field increases in the descending and ascending branches of the major hysteresis loop. In addition, domain configuration is mostly asymmetric with inversion of an applied magnetic field in the hysteretic cycle. Nanomagnetic simulation considering thermal fluctuations of the magnetic moments of the grains explains the nearly stochastic nature of the domain nucleation behavior <span class="hlt">observed</span> in CoCrPt alloy film. With the bit size in high-density magnetic recording media approaching nanometer length scale, one of the fundamental and crucial issues is whether the domain nucleation during magnetization reversal process exhibits a deterministic behavior. Repeatability of local domain nucleation and deterministic switching behavior are basic and essential factors for achieving high performance in high-density magnetic recording [1-3]. Most experimental studies on this issue reported so far have been mainly performed by indirect probes through macroscopic hysteresis loop and Barkhausen pattern measurements, which provide the ensemble-average magnetization. Thus, they are inadequate to gain insight into the domain-nucleation behavior on a nanometer length scale during the magnetization reversal process [4-6]. Very recently, coherent X-ray speckle metrology, where the speckle pattern <span class="hlt">observed</span> in reciprocal space acts as a fingerprint of the domain configurations, was adopted to investigate stochastic behavior in the magnetization reversal of a Co/Pt multilayer film [7,8]. However, no <span class="hlt">direct</span> <span class="hlt">observation</span> on the stochastic behavior of domain nucleation during magnetization reversal in real space at the nanometer scale has yet been reported. The main reason is due to limitations of the microscopic measurement techniques employed. Thus, experimental confirmation for stochastic behavior of domain nucleation together with its clarification has to date remained a scientific challenge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A53S..01D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A53S..01D"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Secondary Organic Aerosol Formation during Cloud Condensation-Evaporation Cycles (SOAaq) in Simulation Chamber Experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Doussin, J. F.; Bregonzio-Rozier, L.; Giorio, C.; Siekmann, F.; Gratien, A.; Temime-Roussel, B.; Ravier, S.; Pangui, E.; Tapparo, A.; Kalberer, M.; Monod, A.</p> <p>2014-12-01</p> <p>Biogenic volatile organic compounds (BVOCs) undergo many reactions in the atmosphere and form a wide range of oxidised and water-soluble compounds. These compounds can partition into atmospheric water droplets, and react within the aqueous phase producing higher molecular weight and/or less volatile compounds which can remain in the particle phase after water evaporation and thus increase the organic aerosol mass (Ervens et al., 2011; Altieri et al., 2008; Couvidat et al., 2013). While this hypothesis is frequently discussed in the literature, so far, almost no <span class="hlt">direct</span> <span class="hlt">observations</span> of such a process have been provided.The aim of the present work is to study SOA formation from isoprene photooxidation during cloud condensation-evaporation cycles.The experiments were performed during the CUMULUS project (CloUd MULtiphase chemistry of organic compoUndS in the troposphere), in the CESAM simulation chamber located at LISA. CESAM is a 4.2 m3 stainless steel chamber equipped with realistic irradiation sources and temperature and relative humidity (RH) controls (Wang et al., 2011). In each experiment, isoprene was <span class="hlt">allowed</span> to oxidize during several hours in the presence on nitrogen oxides under dry conditions. Gas phase compounds were analyzed on-line by a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-ToF-MS), a Fourier Transform Infrared Spectrometer (FTIR), NOx and O3 analyzers. SOA formation was monitored on-line with a Scanning Mobility Particle Sizer (SMPS) and an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS). The experimental protocol was optimised to generate cloud events in the simulation chamber, which <span class="hlt">allowed</span> us to generate clouds lasting for ca. 10 minutes in the presence of light.In all experiments, we <span class="hlt">observed</span> that during cloud formation, water-soluble gas-phase oxidation products (e.g., methylglyoxal, hydroxyacetone, acetaldehyde, formic acid, acetic acid and glycolaldehyde) readily partitioned into cloud droplets and new SOA mass was promptly produced which partly persisted after cloud evaporation. Chemical composition, elemental ratios and density of SOA, measured with the HR-ToF-AMS, were compared before, during cloud formation and after cloud evaporation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhDT.......147C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhDT.......147C"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of extrasolar planets and the development of the gemini planet imager integral field spectrograph</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chilcote, Jeffrey Kaplan</p> <p></p> <p>This thesis is focused on the development and testing of a new instrument capable of finding and characterizing recently-formed Jupiter-sized planets orbiting other stars. To <span class="hlt">observe</span> these planets, I present the design, construction and testing of the Gemini Planet Imager (GPI) Integral Field Spectrograph (IFS). GPI is a facility class instrument for the Gemini Observatory with the primary goal of <span class="hlt">directly</span> detecting young Jovian planets. The GPI IFS utilizes an infrared transmissive lenslet array to sample a rectangular 2.7 x 2.7 arcsecond field of view and provide low-resolution spectra across five bands between 1 and 2.5 mum. The dispersing element can be replaced with a Wollaston prism to provide broadband polarimetry across the same five filter bands. The IFS construction was based at the University of California, Los Angeles in collaboration with the Universite de Montreal, Immervision and Lawrence Livermore National Laboratory. I will present performance results, from in-lab testing, of the Integral Field Spectrograph (IFS) for the Gemini Planet Imager (GPI). The IFS is a large, complex, cryogenic, optical system requiring several years of development and testing. I will present the design and integration of the mechanical and optical performance of the spectrograph optics. The IFS passed its pre-ship review in 2011 and was shipped to University of California, Santa Cruz for integration with the remaining sub-systems of GPI. The UCLA built GPI IFS was integrated with the rest of GPI and is delivering high quality spectral datacubes of GPI's coronagraphic field. Using the NIRC2 instrument located at the Keck Observatory, my collaborators and I <span class="hlt">observed</span> the planetary companion to beta Pictoris in L' (3.5--4.1mum). <span class="hlt">Observations</span> taken in the fall of 2009 and 2012 are used to find the location and inclination of the planet relative to the massive debris disk orbiting beta Pictoris. We find that the planet's orbit has a position angle on the sky of 211.9+/-0.4 degrees, making the planet misaligned by 2.9+/-0.5 degrees from the main disk, consistent with other <span class="hlt">observations</span> that beta Pic b is misaligned with the main disk, and part of the misaligned inner disk. In 2009 & 2012 we find a projected orbital separation of 312.8 +/- 18.3 and 466.35 +/- 8.4 milliarcseconds consistent with an orbital period of ˜ 20 years, and a semi-major axis of ˜ 9 AU as found by Macintosh et al. (2014). During the first commissioning <span class="hlt">observations</span> with the Gemini Planet Imager (GPI), my collaborators and I took the first H-band spectrum of the planetary companion to the nearby young star beta Pictoris. The spectrum has a resolving power of ˜ 45 and demonstrates the distinctive triangular shape of a cool substellar object with low surface gravity. Using atmospheric models, we find an effective temperature of 1650 +/- 50K and a surface gravity of log(g) = 4.0 +/- 0.25 (cgs units). These values agree well with predictions from planetary evolution models for a gas giant with mass between 10 and 12 MJup and age between 10 and 20 Myrs. The spectrum is very similar to a known low mass field brown dwarf but has more flux at the long wavelength end of the filters compared to models. Given the very high signal-to-noise of our spectrum this likely indicates additional physics such as patchy clouds that need to be included in the model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120017353','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120017353"><span id="translatedtitle">The Photochemical Reflectance Index from <span class="hlt">Directional</span> Cornfield Reflectances: <span class="hlt">Observations</span> and Simulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cheng, Yen-Ben; Middleton, Elizabeth M.; Zhang, Qingyuan; Corp, Lawrence A.; Dandois, Jonathan; Kustas, William P.</p> <p>2012-01-01</p> <p>The two-layer Markov chain Analytical Canopy Reflectance Model (ACRM) was linked with in situ hyperspectral leaf optical properties to simulate the Photochemical Reflectance Index (PRI) for a corn crop canopy at three different growth stages. This is an extended study after a successful demonstration of PRI simulations for a cornfield previously conducted at an early vegetative growth stage. Consistent with previous in situ studies, sunlit leaves exhibited lower PRI values than shaded leaves. Since sunlit (shaded) foliage dominates the canopy in the reflectance hotspot (coldspot), the canopy PRI derived from field hyperspectral <span class="hlt">observations</span> displayed sensitivity to both view zenith angle and relative azimuth angle at all growth stages. Consequently, sunlit and shaded canopy sectors were most differentiated when viewed along the azimuth matching the solar principal plane. These <span class="hlt">directional</span> PRI responses associated with sunlit/shaded foliage were successfully reproduced by the ACRM. As before, the simulated PRI values from the current study were closer to in situ values when both sunlit and shaded leaves were utilized as model input data in a two-layer mode, instead of a one-layer mode with sunlit leaves only. Model performance as judged by correlation between in situ and simulated values was strongest for the mature corn crop (r = 0.87, RMSE = 0.0048), followed by the early vegetative stage (r = 0.78; RMSE = 0.0051) and the early senescent stage (r = 0.65; RMSE = 0.0104). Since the benefit of including shaded leaves in the scheme varied across different growth stages, a further analysis was conducted to investigate how variable fractions of sunlit/shaded leaves affect the canopy PRI values expected for a cornfield, with implications for 20 remote sensing monitoring options. Simulations of the sunlit to shaded canopy ratio near 50/50 +/- 10 (e.g., 60/40) matching field <span class="hlt">observations</span> at all growth stages were examined. Our results suggest in the importance of the sunlit/shaded fraction and canopy structure in understanding and interpreting PRI.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2957634','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2957634"><span id="translatedtitle"><span class="hlt">Directly</span> <span class="hlt">Observed</span> Therapy (DOT) for Nonadherent HIV-Infected Youth: Lessons Learned, Challenges Ahead</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Belzer, Marvin; Britto, Paula; Garvie, Patricia A.; Hu, Chengcheng; Graham, Bobbie; Neely, Michael; McSherry, George; Spector, Stephen A.; Flynn, Patricia M.</p> <p>2010-01-01</p> <p>Abstract Adherence to medications is critical to optimizing HIV care and is a major challenge in youth. The utility of <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (DOT) to improve adherence in youth with HIV remains undefined and prompted this pilot study. Four U.S. sites were selected for this 24-week cooperative group study to assess feasibility and to identify the logistics of providing DOT to HIV-infected youth with demonstrated adherence problems. Once-a-day DOT was provided by DOT facilitators at the participant's choice of a community-based location and DOT tapered over 12 weeks to self-administered therapy based on ongoing adherence assessments. Twenty participants, median age 21 years and median CD4 227?cells/?l, were enrolled. Participants chose their homes for 82% of DOT visits. Compliance with recommended DOT visits was (median) 91%, 91%, and 83% at weeks 4, 8, and 12, respectively. Six participants completed >90% of the study-specified DOT visits and successfully progressed to self-administered therapy (DOT success); only half sustained >90% medication adherence 12 weeks after discontinuing DOT. Participants considered DOT successes were more likely to have higher baseline depression scores (p?=?0.046). Via exit surveys participants reported that meeting with the facilitator was easy, DOT increased their motivation to take medications, they felt sad when DOT ended, and 100% would recommend DOT to a friend. In conclusion, this study shows that while community-based DOT is safe, feasible, and as per participant feedback, acceptable to youth, DOT is not for all and the benefits appear short-lived. Depressed youth appear to be one subgroup that would benefit from this intervention. Study findings should help inform the design of larger community-based DOT intervention studies in youth. PMID:20707731</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/161058','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/161058"><span id="translatedtitle">Rates of ingestion and their variability between individual calanoid copepods: <span class="hlt">Direct</span> <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Paffenhoefer, G.A.; Lewis, K.D.; Bundy, M.H. |; Metz, C.</p> <p>1995-12-01</p> <p>The goals of this study were to determine rates of ingestion and fecal pellet release, and their variability, for individual planktonic copepods over extended periods of time (>20 min). Ingestions and rejections of individual cells of the diatom Thalassiosira eccentrica by a adult females of the calanoid Paracalanus aculeatus were <span class="hlt">directly</span> quantified by <span class="hlt">observing</span> individual copepods continuously at cell concentrations ranging from 0.1 to 1.2 mm{sup 3} l{sup {minus}1}. Average ingestion rates increased with increasing food concentration, but were not significantly different between 0.3 and 1.0 mm{sup 3} l{sup {minus}1} (9.8 and 32.7 {mu}g Cl{sup {minus}1}) of T.eccentrica. Rates of cell rejections were low and similar at 0.1 and 0.3. but were significantly higher at 1.0 mm{sup 3} l{sup {minus}1}. The coefficients of variation for average ingestion rates of individual copepods hardly differed between food concentrations, ranging from 17 to 22%, and were close to those for average fecal pellet release intervals which ranged from 15 to 21%. A comparison between individuals at each food concentration found no significant differences at 1.0; at 0.1 and 0.3 mm{sup 3} l{sup {minus}1}, respectively, ingestion rates of four out of five females did not differ significantly from each other. Average intervals between fecal pellet releases were similar at 0.3 and 1.0 mm{sup 3} l{sup {minus}1}. Fecal pellet release intervals between individuals were significantly different at each food concentration; these significant differences were attributed to rather narrow ranges of pellet release intervals of each individual female. Potential sources/causes of variability in the sizes and rates of copepods in the ocean are evaluated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2013-title10-vol1/pdf/CFR-2013-title10-vol1-sec26-115.pdf','CFR2013'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2013-title10-vol1/pdf/CFR-2013-title10-vol1-sec26-115.pdf"><span id="translatedtitle">10 CFR 26.115 - Collecting a urine specimen under <span class="hlt">direct</span> <span class="hlt">observation</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>...<span class="hlt">observed</span> collection on the form. (e) The collector shall ensure that the <span class="hlt">observer</span> is the same gender as the individual. A person of the opposite gender may not act as the <span class="hlt">observer</span> under any conditions. The <span class="hlt">observer</span> may be a different person...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2014-title49-vol1/pdf/CFR-2014-title49-vol1-sec40-67.pdf','CFR2014'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2014-title49-vol1/pdf/CFR-2014-title49-vol1-sec40-67.pdf"><span id="translatedtitle">49 CFR 40.67 - When and how is a <span class="hlt">directly</span> <span class="hlt">observed</span> collection conducted?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-10-01</p> <p>...must ensure that the <span class="hlt">observer</span> is the same gender as the employee. You must never permit an opposite gender person to act as the <span class="hlt">observer</span>. The <span class="hlt">observer</span>...e.g., in order to ensure a same gender <span class="hlt">observer</span>), you must verbally...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2010-title10-vol1/pdf/CFR-2010-title10-vol1-sec26-115.pdf','CFR'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2010-title10-vol1/pdf/CFR-2010-title10-vol1-sec26-115.pdf"><span id="translatedtitle">10 CFR 26.115 - Collecting a urine specimen under <span class="hlt">direct</span> <span class="hlt">observation</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>...<span class="hlt">observed</span> collection on the form. (e) The collector shall ensure that the <span class="hlt">observer</span> is the same gender as the individual. A person of the opposite gender may not act as the <span class="hlt">observer</span> under any conditions. The <span class="hlt">observer</span> may be a different person...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2011-title10-vol1/pdf/CFR-2011-title10-vol1-sec26-115.pdf','CFR2011'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2011-title10-vol1/pdf/CFR-2011-title10-vol1-sec26-115.pdf"><span id="translatedtitle">10 CFR 26.115 - Collecting a urine specimen under <span class="hlt">direct</span> <span class="hlt">observation</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>...<span class="hlt">observed</span> collection on the form. (e) The collector shall ensure that the <span class="hlt">observer</span> is the same gender as the individual. A person of the opposite gender may not act as the <span class="hlt">observer</span> under any conditions. The <span class="hlt">observer</span> may be a different person...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2013-title49-vol1/pdf/CFR-2013-title49-vol1-sec40-67.pdf','CFR2013'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2013-title49-vol1/pdf/CFR-2013-title49-vol1-sec40-67.pdf"><span id="translatedtitle">49 CFR 40.67 - When and how is a <span class="hlt">directly</span> <span class="hlt">observed</span> collection conducted?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-10-01</p> <p>...must ensure that the <span class="hlt">observer</span> is the same gender as the employee. You must never permit an opposite gender person to act as the <span class="hlt">observer</span>. The <span class="hlt">observer</span>...e.g., in order to ensure a same gender <span class="hlt">observer</span>), you must verbally...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2010-title49-vol1/pdf/CFR-2010-title49-vol1-sec40-67.pdf','CFR'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2010-title49-vol1/pdf/CFR-2010-title49-vol1-sec40-67.pdf"><span id="translatedtitle">49 CFR 40.67 - When and how is a <span class="hlt">directly</span> <span class="hlt">observed</span> collection conducted?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-10-01</p> <p>...must ensure that the <span class="hlt">observer</span> is the same gender as the employee. You must never permit an opposite gender person to act as the <span class="hlt">observer</span>. The <span class="hlt">observer</span>...e.g., in order to ensure a same gender <span class="hlt">observer</span>), you must verbally...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2012-title49-vol1/pdf/CFR-2012-title49-vol1-sec40-67.pdf','CFR2012'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2012-title49-vol1/pdf/CFR-2012-title49-vol1-sec40-67.pdf"><span id="translatedtitle">49 CFR 40.67 - When and how is a <span class="hlt">directly</span> <span class="hlt">observed</span> collection conducted?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-10-01</p> <p>...must ensure that the <span class="hlt">observer</span> is the same gender as the employee. You must never permit an opposite gender person to act as the <span class="hlt">observer</span>. The <span class="hlt">observer</span>...e.g., in order to ensure a same gender <span class="hlt">observer</span>), you must verbally...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2012-title10-vol1/pdf/CFR-2012-title10-vol1-sec26-115.pdf','CFR2012'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2012-title10-vol1/pdf/CFR-2012-title10-vol1-sec26-115.pdf"><span id="translatedtitle">10 CFR 26.115 - Collecting a urine specimen under <span class="hlt">direct</span> <span class="hlt">observation</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>...<span class="hlt">observed</span> collection on the form. (e) The collector shall ensure that the <span class="hlt">observer</span> is the same gender as the individual. A person of the opposite gender may not act as the <span class="hlt">observer</span> under any conditions. The <span class="hlt">observer</span> may be a different person...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2011-title49-vol1/pdf/CFR-2011-title49-vol1-sec40-67.pdf','CFR2011'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2011-title49-vol1/pdf/CFR-2011-title49-vol1-sec40-67.pdf"><span id="translatedtitle">49 CFR 40.67 - When and how is a <span class="hlt">directly</span> <span class="hlt">observed</span> collection conducted?</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-10-01</p> <p>...must ensure that the <span class="hlt">observer</span> is the same gender as the employee. You must never permit an opposite gender person to act as the <span class="hlt">observer</span>. The <span class="hlt">observer</span>...e.g., in order to ensure a same gender <span class="hlt">observer</span>), you must verbally...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011DSRII..58.2613V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011DSRII..58.2613V"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of increasing CO 2 in the Weddell Gyre along the Prime Meridian during 1973-2008</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>van Heuven, Steven M. A. C.; Hoppema, Mario; Huhn, Oliver; Slagter, Hans A.; de Baar, Hein J. W.</p> <p>2011-12-01</p> <p>The World Ocean takes up a large portion of the anthropogenic CO 2 emitted into the atmosphere. Determining the resulting increase in dissolved inorganic carbon ( CT, expressed in ?mol kg -1) is challenging, particularly in the sub-surface and deep Southern Ocean where the time rate of change of CT (in ?mol kg -1 decade -1) is commonly expected to be low. We present a determination of this time trend of CT in a dataset of measurements that spans 35 years comprising 10 cruises in the 1973-2008 period along the 0°-meridian in the Weddell Gyre. The inclusion of many cruises aims to generate results that are more robust than may be obtained by taking the difference between only one pair of cruises, each of which may suffer from errors in accuracy. To further improve consistency between cruises, data were adjusted in order to obtain time-invariant values of CT (and other relevant parameters) over the 35 years in the least ventilated local water body, this comprising the deeper Warm Deep Water (WDW) and upper Weddell Sea Deep Water (WSDW). It is assumed that this normalization procedure will <span class="hlt">allow</span> trends in CT in the more intensely ventilated water masses to be more clearly <span class="hlt">observed</span>. Time trends were determined <span class="hlt">directly</span> in measurements of CT, and alternatively in back-calculated values of preformed CT ( CT0; i.e., the CT of the water at the time that it lost contact with the atmosphere). The determined time trends may be attributed to a combination of natural variability (in hydrography or biogeochemistry) and increased uptake of anthropogenic CO 2 from the atmosphere. In order to separate these natural and anthropogenic components, an analysis of the residuals of a multivariate linear regression (MLR), involving the complete time series of all 10 cruises, was additionally performed. This approach is referred to as the Time Series Residuals (TSR) approach. Using the <span class="hlt">direct</span> method, the time trends of CT in the WSDW are quite small and non-significant at +0.176±0.321 ?mol kg -1 decade -1. On the other hand, the measured concentration of CT in the Weddell Sea Bottom Water (WSBW) is shown to rise slowly but significantly over the period from 1973 to 2008 at a rate of +1.151±0.563 ?mol kg -1 decade -1. The spatial distribution of these determined increases of CT in the deep Weddell Gyre closely resembles that of the increase of the anthropogenic tracer CFC-12, this strong similarity supporting a mostly anthropogenic cause for the increasing trend of CT. Time trends in back-calculated values of CT0 appear to be obscured due to uncertainties in the measurements of O 2. Finally, the shallow waters (<200 m depth) do not <span class="hlt">allow</span> for interpretation since these are strongly affected by seasonality. Due to the small time trend signal in the WSBW, the TSR approach does not <span class="hlt">allow</span> for unambiguous attribution of the <span class="hlt">observed</span> trend in CT in the WSBW. The residuals of the TSR method do exhibit a time trend (considered representative of the time trend of Cant) of +0.445±0.405 ?mol kg -1 decade -1 (i.e., only 38% of the <span class="hlt">direct</span> <span class="hlt">observed</span> time trend in CT) thus only partly supporting the attribution of the measured time trend of CT to uptake of anthropogenic CO 2. Another TSR-derived result suggests that there is no significant time trend of biogeochemical changes. A time trend in hydrography of mixing between two deep water masses does exist, as evidenced by a slight positive time trend in the temperature of the WSBW, but is inadequate to explain the time trend of CT. After all, the time trend in measured CT is most straightforwardly ascribed entirely to uptake of Cant, and assuming an exponentially growing history of storage, the <span class="hlt">observed</span> increase of CT in the WSBW suggests that a total amount of Cant of 6±3 ?mol kg -1 has accumulated in this water mass between the onset of the Industrial Revolution and 1995. Extrapolating the determined time trend, the rate of storage of Cant in the deep Weddell Gyre (>3000 m, west of 20°E) is calculated to be about 12±6 TgC yr -1 over the 1973-2008 period. This rate of storage is likely somewha</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1440858','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1440858"><span id="translatedtitle">The <span class="hlt">Directly</span> <span class="hlt">Observed</span> Therapy Short-Course (DOTS) strategy in Samara Oblast, Russian Federation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Balabanova, Y; Drobniewski, F; Fedorin, I; Zakharova, S; Nikolayevskyy, V; Atun, R; Coker, R</p> <p>2006-01-01</p> <p>Background The World Health Organisation (WHO) defines Russia as one of the 22 highest-burden countries for tuberculosis (TB). The WHO <span class="hlt">Directly</span> <span class="hlt">Observed</span> Treatment Short Course (DOTS) strategy employing a standardised treatment for 6 months produces the highest cure rates for drug sensitive TB. The Russian TB service traditionally employed individualised treatment. The purpose of this study was to implement a DOTS programme in the civilian and prison sectors of Samara Region of Russia, describe the clinical features and outcomes of recruited patients, determine the proportion of individuals in the cohorts who were infected with drug resistant TB, the degree to which resistance was attributed to the Beijing TB strain family and establish risk factors for drug resistance. Methods prospective study Results 2,099 patients were recruited overall. Treatment outcomes were analysed for patients recruited up to the third quarter of 2003 (n = 920). 75.3% of patients were successfully treated. Unsuccessful outcomes occurred in 7.3% of cases; 3.6% of patients died during treatment, with a significantly higher proportion of smear-positive cases dying compared to smear-negative cases. 14.0% were lost and transferred out. A high proportion of new cases (948 sequential culture-proven TB cases) had tuberculosis that was resistant to first-line drugs; (24.9% isoniazid resistant; 20.3% rifampicin resistant; 17.3% multidrug resistant tuberculosis). Molecular epidemiological analysis demonstrated that half of all isolated strains (50.7%; 375/740) belonged to the Beijing family. Drug resistance including MDR TB was strongly associated with infection with the Beijing strain (for MDR TB, 35.2% in Beijing strains versus 9.5% in non-Beijing strains, OR-5.2. Risk factors for multidrug resistant tuberculosis were: being a prisoner (OR 4.4), having a relapse of tuberculosis (OR 3.5), being infected with a Beijing family TB strain (OR 6.5) and having an unsuccessful outcome from treatment (OR 5.0). Conclusion The implementation of DOTS in Samara, Russia, was feasible and successful. Drug resistant tuberculosis rates in new cases were high and challenge successful outcomes from a conventional DOTS programme alone. PMID:16556324</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title44-vol1/pdf/CFR-2013-title44-vol1-sec206-228.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title44-vol1/pdf/CFR-2013-title44-vol1-sec206-228.pdf"><span id="translatedtitle">44 CFR 206.228 - <span class="hlt">Allowable</span> costs.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-10-01</p> <p>... <span class="hlt">Allowable</span> costs. General policies for determining <span class="hlt">allowable</span> costs are established in 44 CFR 13.22. Exceptions to those policies as <span class="hlt">allowed</span> in 44 CFR 13.4 and 13.6 are explained below. (a) Eligible <span class="hlt">direct</span>... accordance with 44 CFR part 207. (b)...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www-pord.ucsd.edu/~ltalley/okhotsk/PAPERS/shcherbina_etal_Pt1_JGRO_2004.pdf','EPRINT'); return false;" href="http://www-pord.ucsd.edu/~ltalley/okhotsk/PAPERS/shcherbina_etal_Pt1_JGRO_2004.pdf"><span id="translatedtitle">Dense water formation on the northwestern shelf of the Okhotsk Sea: 1. <span class="hlt">Direct</span> <span class="hlt">observations</span> of brine rejection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Talley, Lynne D.</p> <p></p> <p>Dense water formation on the northwestern shelf of the Okhotsk Sea: 1. <span class="hlt">Direct</span> <span class="hlt">observations</span> of brine rejection in the coastal polynya on the northwestern shelf of the Okhotsk Sea was studied using two bottom; 4243 Oceanography: General: Marginal and semienclosed seas; KEYWORDS: Okhotsk Sea, brine rejection</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://time.kaist.ac.kr/pub/83.pdf','EPRINT'); return false;" href="http://time.kaist.ac.kr/pub/83.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Cooperative Protein Structural Dynamics of Homodimeric Hemoglobin from 100 ps to 10 ms with Pump-Probe</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Ihee, Hyotcherl</p> <p></p> <p><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Cooperative Protein Structural Dynamics of Homodimeric Hemoglobin from 100 ps dynamics of wild-type homodimeric hemoglobin (HbI) from the clam Scapharca inaequivalvis and its F97Y into the protein structural dynamics. INTRODUCTION The allosteric structural transition of hemoglobin induced</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ750846.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ750846.pdf"><span id="translatedtitle">Establishing the Feasibility of <span class="hlt">Direct</span> <span class="hlt">Observation</span> in the Assessment of Tics in Children with Chronic Tic Disorders</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Himle, Michael B.; Chang, Susanna; Woods, Douglas W.; Pearlman, Amanda; Buzzella, Brian; Bunaciu, Liviu; Piacentini, John C.</p> <p>2006-01-01</p> <p>Behavior analysis has been at the forefront in establishing effective treatments for children and adults with chronic tic disorders. As is customary in behavior analysis, the efficacy of these treatments has been established using <span class="hlt">direct-observation</span> assessment methods. Although behavior-analytic treatments have enjoyed acceptance and integration…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.nature.com/nphys/journal/v6/n5/pdf/nphys1628.pdf','EPRINT'); return false;" href="http://www.nature.com/nphys/journal/v6/n5/pdf/nphys1628.pdf"><span id="translatedtitle">PUBLISHED ONLINE: 11 APRIL 2010 | DOI: 10.1038/NPHYS1628 <span class="hlt">Direct</span> <span class="hlt">observation</span> of magnetic monopole defects</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Loss, Daniel</p> <p></p> <p>to the same emergent excitations of the magnetic structure. In our artificial kagome ice, the magnetic chargeLETTERS PUBLISHED ONLINE: 11 APRIL 2010 | DOI: 10.1038/NPHYS1628 <span class="hlt">Direct</span> <span class="hlt">observation</span> of magnetic monopole defects in an artificial spin-ice system S. Ladak, D. E. Read, G. K. Perkins, L. F. Cohen and W. R</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www-surface.phys.s.u-tokyo.ac.jp/papers/2015/Matetskiy-APL-2015Sep.pdf','EPRINT'); return false;" href="http://www-surface.phys.s.u-tokyo.ac.jp/papers/2015/Matetskiy-APL-2015Sep.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of a gap opening in topological interface states of MnSe/Bi2Se3 heterostructure</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Hasegawa, Shuji</p> <p></p> <p><span class="hlt">Direct</span> <span class="hlt">observation</span> of a gap opening in topological interface states of MnSe/Bi2Se3 heterostructure by the AIP Publishing Articles you may be interested in Structural properties of Bi2- x Mn x Se3 thin films of the topological insulator Bi2Se3 on Si(111): Growth mode, lattice parameter, and strain state Appl. Phys. Lett</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021482&hterms=streaming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dstreaming','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021482&hterms=streaming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dstreaming"><span id="translatedtitle">Bi-<span class="hlt">directional</span> streaming of halo electrons in interplanetary plasma clouds <span class="hlt">observed</span> between 0.3 and 1 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ivory, K.; Schwenn, R.</p> <p>1995-01-01</p> <p>The solar wind data obtained from the two Helios solar probes in the years 1974 to 1986 were systematically searched for the occurrence of bi-<span class="hlt">directional</span> electron events. Most often these events are found in conjunction with shock associated magnetic clouds. The implications of these <span class="hlt">observations</span> for the topology of interplanetary plasma clouds are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26510096','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26510096"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Short-Range Structural Coherence During a Charge Transfer Induced Spin Transition in a CoFe Prussian Blue Analogue by Transmission Electron Microscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Itoi, Miho; Jike, Toyoharu; Nishio-Hamane, Daisuke; Udagawa, Seiichi; Tsuda, Tetsuya; Kuwabata, Susumu; Boukheddaden, Kamel; Andrus, Matthew J; Talham, Daniel R</p> <p>2015-11-25</p> <p>The local structure within the Co-Fe atomic array of the photoswitchable coordination polymer magnet, K0.3Co[Fe(CN)6]0.77·nH2O, is <span class="hlt">directly</span> <span class="hlt">observed</span> during charge transfer induced spin transition (CTIST), a solid-solid phase change, using high-resolution transmission electron microscopy (HRTEM). Along with the low-spin (LS) or thermally quenched high-spin (HS) states normally <span class="hlt">observed</span> in CTIST solids at low temperature, slow cooling of K0.3Co[Fe(CN)6]0.77·nH2O results in an intermediate phase containing both HS and LS domains with short coherence length. By mapping individual metal-metal distances, the nanometer-scale HS domains are <span class="hlt">directly</span> visualized within the LS array. Temperature-dependent analyses <span class="hlt">allow</span> monitoring of HS domain coarsening along the warming branch of the CTIST, providing <span class="hlt">direct</span> visualization of the elastic process and insight into the mechanism of phase propagation. Normally sensitive to electron beam damage, the low-temperature TEM measurements of the porous coordination polymer are enabled by using appropriate ionic liquids instead of usual conductive thin-film coatings, an approach that should find general utility in related classes of materials. PMID:26510096</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED127013.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED127013.pdf"><span id="translatedtitle"><span class="hlt">Observational</span> Child Study: An Empirical Analysis of Recent Trends and <span class="hlt">Directions</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Susman, Elizabeth J.; And Others</p> <p></p> <p>The analysis reported here examined the progress of <span class="hlt">observational</span> child study from 1960 through 1975. Naturalistic <span class="hlt">observational</span> studies were described as heuristic, highly realistic, relevant to important social problems and oriented toward significant theoretical issues. Fifteen journals encompassing child development, clinical and educational…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/CFR-2014-title10-vol1/pdf/CFR-2014-title10-vol1-sec26-115.pdf','CFR2014'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/CFR-2014-title10-vol1/pdf/CFR-2014-title10-vol1-sec26-115.pdf"><span id="translatedtitle">10 CFR 26.115 - Collecting a urine specimen under <span class="hlt">direct</span> <span class="hlt">observation</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>...<span class="hlt">observer</span> shall instruct the donor to adjust his or her clothing to ensure that the area of the donor's body between the waist and knees is exposed; (2) The <span class="hlt">observer</span> shall watch the donor urinate into the collection container. Specifically, the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22310683','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22310683"><span id="translatedtitle"><span class="hlt">Direct</span> electrical <span class="hlt">observation</span> of plasma wave-related effects in GaN-based two-dimensional electron gases</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhao, Y.; Chen, W.; Li, W.; Zhu, M.; Yue, Y.; Song, B.; Encomendero, J.; Xing, H.; Fay, P.; Sensale-Rodriguez, B.</p> <p>2014-10-27</p> <p>In this work, signatures of plasma waves in GaN-based high electron mobility transistors were <span class="hlt">observed</span> by <span class="hlt">direct</span> electrical measurement at room temperature. Periodic grating-gate device structures were fabricated and characterized by on-wafer G-band (140–220?GHz) s-parameter measurements as a function of gate bias voltage and device geometry. A physics-based equivalent circuit model was used to assist in interpreting the measured s-parameters. The kinetic inductance extracted from the measurement data matches well with theoretical predictions, consistent with <span class="hlt">direct</span> <span class="hlt">observation</span> of plasma wave-related effects in GaN-channel devices at room temperature. This <span class="hlt">observation</span> of electrically significant room-temperature plasma-wave effects in GaN-channel devices may have implications for future millimeter-wave and THz device concepts and designs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/574666','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/574666"><span id="translatedtitle">The underlying magnetic field <span class="hlt">direction</span> in Ulysses <span class="hlt">observations</span> of the southern polar heliosphere</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Forsyth, R.J.; Balogh, A.; Smith, E.J.; Murphy, N.; McComas, D.J.</p> <p>1996-07-01</p> <p>Magnetic field data provided by the Ulysses spacecraft between May 1993 and January 1995 are presented for the south latitudes 30-80 dg. The deflections of the magnetic field <span class="hlt">direction</span> are attributed to the intense Alfven waves. {copyright} {bold 1997 American Institute of Physics.}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Time+AND+Series+AND+Data+AND+Analysis+AND+Theory.&pg=2&id=EJ898763','ERIC'); return false;" href="http://eric.ed.gov/?q=Time+AND+Series+AND+Data+AND+Analysis+AND+Theory.&pg=2&id=EJ898763"><span id="translatedtitle"><span class="hlt">Direct</span> Behavior Rating (DBR): Generalizability and Dependability across Raters and <span class="hlt">Observations</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Christ, Theodore J.; Riley-Tillman, T. Chris; Chafouleas, Sandra M.; Boice, Christina H.</p> <p>2010-01-01</p> <p>Generalizability theory was used to examine the generalizability and dependability of outcomes from two single-item <span class="hlt">Direct</span> Behavior Rating (DBR) scales: DBR of actively manipulating and DBR of visually distracted. DBR is a behavioral assessment tool with specific instrumentation and procedures that can be used by a variety of service delivery…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=PARENTING+AND+STYLES+AND+SOCIAL+AND+ANXIETY+AND+ADOLESCENTS&id=EJ861677','ERIC'); return false;" href="http://eric.ed.gov/?q=PARENTING+AND+STYLES+AND+SOCIAL+AND+ANXIETY+AND+ADOLESCENTS&id=EJ861677"><span id="translatedtitle">Influence of Parenting Factors on Childhood Social Anxiety: <span class="hlt">Direct</span> <span class="hlt">Observation</span> of Parental Warmth and Control</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Rork, Kristine E.; Morris, Tracy L.</p> <p>2009-01-01</p> <p>The purpose of the present study is to determine the association of parenting behaviors and social anxiety in children. Three parental factors--including parental socialization, control, and warmth--were investigated in a sample of 31 two-parent families. Rather than solely relying upon retrospective questionnaires, this study incorporated <span class="hlt">direct</span>…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.es.lancs.ac.uk/people/nickc/JonesChappell&Tych2014SI.pdf','EPRINT'); return false;" href="http://www.es.lancs.ac.uk/people/nickc/JonesChappell&Tych2014SI.pdf"><span id="translatedtitle">First dynamic model of dissolved organic carbon derived <span class="hlt">directly</span> from high frequency <span class="hlt">observations</span> through contiguous storms</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Chappell, Nick A</p> <p></p> <p>S1 First dynamic model of dissolved organic carbon derived <span class="hlt">directly</span> from high frequency to a galvanised steel structure. Two 86 Ah sealed leisure batteries connected in series were used to ensure a continuous power supply guaranteed in excess of 12.0 V DC; these were exchanged for fully recharged units</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1613957P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1613957P"><span id="translatedtitle">A DTN-ready application for the real-time dissemination of Earth <span class="hlt">Observation</span> data received by <span class="hlt">Direct</span> Readout stations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paronis, Dimitris; Daglis, Ioannis A.; Diamantopoulos, Sotirios; Tsaoussidis, Vassilis; Tsigkanos, Antonis; Ghita, Bogdan; Evans, Michael</p> <p>2014-05-01</p> <p>The majority of Earth <span class="hlt">observation</span> satellites operate in low Earth sun-synchronous orbit and transmit data captured by a variety of sensors. The effective dissemination of satellite data in real-time is a crucial parameter for disaster monitoring in particular. Generally, a spacecraft collects data and then stores it on-board until it passes over dedicated ground stations to transmit the data. Additionally, some satellites (e.g. Terra, Aqua, Suomi-NPP, NOAA series satellites) have the so-called <span class="hlt">Direct</span> Broadcast (DB) capability, which is based on a real-time data transmission sub-system. Compatible <span class="hlt">Direct</span> Readout (DR) stations in <span class="hlt">direct</span> line of sight are able to receive these transmissions. To date data exchange between DR stations have not been fully exploited for real-time data dissemination. Stations around the world store data locally, which is then disseminated on demand via Internet gateways based on the standard TCP-IP protocols. On the other hand, Delay Tolerant Networks (DTNs), which deliver data by enabling store-and-forward transmission in order to cope with link failures, service disruptions and network congestion, could prove as an alternative/complementary transmission mechanism for the efficient dissemination of data. The DTN architecture <span class="hlt">allows</span> for efficient utilization of the network, using in-network storage and taking advantage of the network availability among the interconnected nodes. Although DTNs were originally developed for high-propagation delay, challenged connectivity environments such as deep space, the broader research community has investigated possible architectural enhancements for various emerging applications (e.g., terrestrial infrastructure, ground-to-air communications, content retrieval and dissemination). In this paper, a scheme for the effective dissemination of DB data is conceptualized, designed and implemented based on store-and-forward transmission capabilities provided by DTNs. For demonstration purposes, a set-up has been designed and implemented which emulates the interconnection and data transmission of various HRPT/AVHRR DR stations based on pre-scheduled contacts via the DTN architecture. According to the scheme adopted, as soon as the satellite scans the earth and after image reception, a contact is established with a DTN node and data transmission is initiated. These DR stations form a DTN overlay, taking advantage of the routing, transport and security mechanisms developed. Most importantly, data received at a station can automatically be forwarded to any other station belonging to the same "interest" group through a flexible DTN multicasting mechanism. Thus, a composite image of an extended area (or potentially an image of the entire globe, depending on the interest groups formed is constructed in each node in an imperceptible way. Upon processing of the received data streams, stations are able to further disseminate new products to other interested third party entities exploiting the DTN overlay and the filtering capabilities provided by a web-based tool. The work leading to this paper has received funding from the European Union's Seventh Framework Programme (FP7-SPACE-2010-1) under grant agreement no. 263330 for the SDR (Space-Data Routers for Exploiting Space Data) collaborative research project. This paper reflects only the authors' views and the Union is not liable for any use that may be made of the information contained therein.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/978629','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/978629"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the mass renormalization in SrVO3 by angle resolved photoemission spectroscopy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yoshida, t.</p> <p>2010-05-03</p> <p>We have performed an angle-resolved photoemission study of the three-dimensional perovskite-type SrVO{sub 3}. <span class="hlt">Observed</span> spectral weight distribution of the coherent part in the momentum space shows cylindrical Fermi surfaces consisting of the V 3d t{sub 2g} orbitals as predicted by local-density approximation (LDA) band-structure calculation. The <span class="hlt">observed</span> energy dispersion shows a moderately enhanced effective mass compared to the LDA results, corresponding to the effective mass enhancement seen in the thermodynamic properties. Contributions from the bulk and surface electronic structures to the <span class="hlt">observed</span> spectra are discussed based on model calculations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850027580','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850027580"><span id="translatedtitle"><span class="hlt">Observation</span> of <span class="hlt">direct</span> hadronic pairs in nucleus-nucleus collisions in JACEE emulsion chambers</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burnett, T. H.; Dake, S.; Fuki, M.; Gregory, J. C.; Hayashi, T.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W. V.; Jurak, A.</p> <p>1985-01-01</p> <p>In a number of high energy ( or = 1 TeV/amu) nucleus-nucleus collisions <span class="hlt">observed</span> in Japanese-American Cooperative Emulsion Experiment (JACEE) emulsion chambers, nonrandom spatial association of produced charged particles, mostly hadronic pairs, are <span class="hlt">observed</span>. Similar narrow pairs are <span class="hlt">observed</span> in about 100 events at much low energy (20 to 60 GeV/amu). Analysis shows that 30 to 50% of Pair abundances are understood by the Hambury-Brown-Twiss effect, and the remainder seems to require other explanations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21304997','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21304997"><span id="translatedtitle"><span class="hlt">OBSERVATIONAL</span> EVIDENCE OF A CORONAL MASS EJECTION DISTORTION <span class="hlt">DIRECTLY</span> ATTRIBUTABLE TO A STRUCTURED SOLAR WIND</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Savani, N. P.; Owens, M. J.; Forsyth, R. J.; Rouillard, A. P.; Davies, J. A.</p> <p>2010-05-01</p> <p>We present the first <span class="hlt">observational</span> evidence of the near-Sun distortion of the leading edge of a coronal mass ejection (CME) by the ambient solar wind into a concave structure. On 2007 November 14, a CME was <span class="hlt">observed</span> by coronagraphs onboard the STEREO-B spacecraft, possessing a circular cross section. Subsequently the CME passed through the field of view of the STEREO-B Heliospheric Imagers where the leading edge was <span class="hlt">observed</span> to distort into an increasingly concave structure. The CME <span class="hlt">observations</span> are compared to an analytical flux rope model constrained by a magnetohydrodynamic solar wind solution. The resultant bimodal speed profile is used to kinematically distort a circular structure that replicates the initial shape of the CME. The CME morphology is found to change rapidly over a relatively short distance. This indicates an approximate radial distance in the heliosphere where the solar wind forces begin to dominate over the magnetic forces of the CME influencing the shape of the CME.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012LPI....43.2352S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012LPI....43.2352S"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observations</span> of Lunar Pickup Ions in the Magnetosphere Tail-Lobes by ARTEMIS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Samad, R. L.; Poppe, A. R.; Halekas, J. S.; Delory, G. T.; Angelopoulos, V.; Farrell, W. M.</p> <p>2012-03-01</p> <p>We present ARTEMIS <span class="hlt">observations</span> of pickup ions on the dayside of the Moon in the terrestrial magnetotail lobes. We attempt to determine the composition of these ions, presumably from either the surface or the exosphere, via ion tracing simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22086432','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22086432"><span id="translatedtitle"><span class="hlt">DIRECT</span> <span class="hlt">OBSERVATION</span> OF THE TURBULENT emf AND TRANSPORT OF MAGNETIC FIELD IN A LIQUID SODIUM EXPERIMENT</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rahbarnia, Kian; Brown, Benjamin P.; Clark, Mike M.; Kaplan, Elliot J.; Nornberg, Mark D.; Rasmus, Alex M.; Taylor, Nicholas Zane; Forest, Cary B.; Jenko, Frank; Limone, Angelo; Pinton, Jean-Francois; Plihon, Nicolas; Verhille, Gautier</p> <p>2012-11-10</p> <p>For the first time, we have <span class="hlt">directly</span> measured the transport of a vector magnetic field by isotropic turbulence in a high Reynolds number liquid metal flow. In analogy with <span class="hlt">direct</span> measurements of the turbulent Reynolds stress (turbulent viscosity) that governs momentum transport, we have measured the turbulent electromotive force (emf) by simultaneously measuring three components of velocity and magnetic fields, and computed the correlations that lead to mean-field current generation. Furthermore, we show that this turbulent emf tends to oppose and cancel out the local current, acting to increase the effective resistivity of the medium, i.e., it acts as an enhanced magnetic diffusivity. This has important implications for turbulent transport in astrophysical objects, particularly in dynamos and accretion disks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26198741','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26198741"><span id="translatedtitle"><span class="hlt">Direct</span> experimental <span class="hlt">observation</span> of weakly-bound character of the attached electron in europium anion.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cheng, Shi-Bo; Castleman, A W</p> <p>2015-01-01</p> <p><span class="hlt">Direct</span> experimental determination of precise electron affinities (EAs) of lanthanides is a longstanding challenge to experimentalists. Considerable debate exists in previous experiment and theory, hindering the complete understanding about the properties of the atomic anions. Herein, we report the first precise photoelectron imaging spectroscopy of europium (Eu), with the aim of eliminating prior contradictions. The measured EA (0.116?±?0.013?eV) of Eu is in excellent agreement with recently reported theoretical predictions, providing <span class="hlt">direct</span> spectroscopic evidence that the additional electron is weakly attached. Additionally, a new experimental strategy is proposed that can significantly increase the yield of the lanthanide anions, opening up the best opportunity to complete the periodic table of the atomic anions. The present findings not only serve to resolve previous discrepancy but also will help in improving the depth and accuracy of our understanding about the fundamental properties of the atomic anions. PMID:26198741</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...512414C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...512414C"><span id="translatedtitle"><span class="hlt">Direct</span> experimental <span class="hlt">observation</span> of weakly-bound character of the attached electron in europium anion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cheng, Shi-Bo; Castleman, A. W.</p> <p>2015-07-01</p> <p><span class="hlt">Direct</span> experimental determination of precise electron affinities (EAs) of lanthanides is a longstanding challenge to experimentalists. Considerable debate exists in previous experiment and theory, hindering the complete understanding about the properties of the atomic anions. Herein, we report the first precise photoelectron imaging spectroscopy of europium (Eu), with the aim of eliminating prior contradictions. The measured EA (0.116?±?0.013?eV) of Eu is in excellent agreement with recently reported theoretical predictions, providing <span class="hlt">direct</span> spectroscopic evidence that the additional electron is weakly attached. Additionally, a new experimental strategy is proposed that can significantly increase the yield of the lanthanide anions, opening up the best opportunity to complete the periodic table of the atomic anions. The present findings not only serve to resolve previous discrepancy but also will help in improving the depth and accuracy of our understanding about the fundamental properties of the atomic anions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4510523','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4510523"><span id="translatedtitle"><span class="hlt">Direct</span> experimental <span class="hlt">observation</span> of weakly-bound character of the attached electron in europium anion</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cheng, Shi-Bo; Castleman, A. W.</p> <p>2015-01-01</p> <p><span class="hlt">Direct</span> experimental determination of precise electron affinities (EAs) of lanthanides is a longstanding challenge to experimentalists. Considerable debate exists in previous experiment and theory, hindering the complete understanding about the properties of the atomic anions. Herein, we report the first precise photoelectron imaging spectroscopy of europium (Eu), with the aim of eliminating prior contradictions. The measured EA (0.116?±?0.013?eV) of Eu is in excellent agreement with recently reported theoretical predictions, providing <span class="hlt">direct</span> spectroscopic evidence that the additional electron is weakly attached. Additionally, a new experimental strategy is proposed that can significantly increase the yield of the lanthanide anions, opening up the best opportunity to complete the periodic table of the atomic anions. The present findings not only serve to resolve previous discrepancy but also will help in improving the depth and accuracy of our understanding about the fundamental properties of the atomic anions. PMID:26198741</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21072830','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21072830"><span id="translatedtitle"><span class="hlt">Direct</span> ECC Bypass Phenomena During LBLOCA Reflood Phase <span class="hlt">Observed</span> in the MIDAS Test: Facility</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yun, B.J.; Kwon, T.S.; Euh, D.J.; Chu, I.C.; Song, C.H.; Park, J.K.</p> <p>2002-07-01</p> <p>One of the advanced design features of the APR-1400, <span class="hlt">direct</span> vessel injection (DVI) system is being considered instead of conventional cold leg injection (CLI) system. It is known that the DVI system greatly enhances the reliability of the emergency core cooling (ECC) system. However, there is still a dispute on its performance in terms of water delivery to the reactor core during the reflood phase of a large-break loss-of-coolant accident (LOCA). Thus, experimental validation is in progress. In this paper, test results of a <span class="hlt">direct</span> ECC bypass performed in the steam-water test facility called MIDAS (Multi-dimensional Investigation in Downcomer Annulus Simulation) is presented. The test condition is determined, based on the preliminary analysis of TRAC code, by applying the 'modified linear scaling method' with the 1/4.93 length scale. From the tests, ECC <span class="hlt">direct</span> bypass fraction, steam condensation rate and information on the flow distribution in the upper annulus downcomer region is obtained. (authors)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26325974','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26325974"><span id="translatedtitle">How fast can a baseball spin before an <span class="hlt">observer</span> can't tell the <span class="hlt">direction</span> of rotation?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shapiro, Arthur; Newport, Jonathan; DeVries, Bree</p> <p>2015-09-01</p> <p>In baseball, a pitcher throws a 3" ball toward a batter positioned 60.5 feet away. Shapiro et al (2009, 2011) hypothesized that a batter's perception of a pitch could be influenced by changes in the ball's retinal location (i.e., whether the batter views the ball centrally or peripherally). One question concerns whether a curveball spins too fast for a batter to discern the <span class="hlt">direction</span> of spin. To address this question, we constructed a device in which a microcontroller spins a motor at rates up to 3000 rpm. A baseball rested on a driveshaft extending from the motor; an LCD shutter controlled the presentation duration (set at .6 sec); steady LED lights illuminated the ball. The <span class="hlt">observer</span> viewed the ball from a distance of 140 cm (ball subtended 3.2 deg) and pressed one of two buttons to indicate the <span class="hlt">direction</span> of perceived spin. Experiment 1: The ball was presented at rotation rates between 500 and 2500 rpm (40 trials in random order; half the trial were clockwise, half counter clockwise). Experiment 2: Similar set up, but on different sets of trials the <span class="hlt">observers</span> viewed the ball either centrally or 10 deg in the periphery. Experiment 3: On different sets of trials the ball was positioned on the motor in a "2-seam" or a "4-seam" configuration. For all conditions, at rates up 1200 rpm, <span class="hlt">observers</span> were typically correct 100% of the time, but near 2000 rpm, <span class="hlt">observers</span> were typically at chance. Peripheral viewing and spin configuration had little effect on <span class="hlt">observer</span>'s ability to identify spin <span class="hlt">direction</span>. Since an MLB curveball spins between 1400 and 1800 rpm, these pitches approach the limit of our perceptual resolution. The minor effect of peripheral viewing and spin configuration suggest, surprisingly, that our ability to perceive spin <span class="hlt">direction</span> may be mediated by low spatial frequency channels. Meeting abstract presented at VSS 2015. PMID:26325974</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22341976','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22341976"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of plasma upflows and condensation in a catastrophically cooling solar transition region loop</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Orange, N. B.; Chesny, D. L.; Oluseyi, H. M.; Hesterly, K.; Patel, M.; Champey, P.</p> <p>2013-12-01</p> <p>Minimal <span class="hlt">observational</span> evidence exists for fast transition region (TR) upflows in the presence of cool loops. <span class="hlt">Observations</span> of such occurrences challenge notions of standard solar atmospheric heating models as well as their description of bright TR emission. Using the EUV Imaging Spectrometer on board Hinode, we <span class="hlt">observe</span> fast upflows (v {sub ?} ? –10 km s{sup –1}) over multiple TR temperatures (5.8 ?log T ? 6.0) at the footpoint sites of a cool loop (log T ? 6.0). Prior to cool loop energizing, asymmetric flows of +5 km s{sup –1} and –60 km s{sup –1} are <span class="hlt">observed</span> at footpoint sites. These flows, speeds, and patterns occur simultaneously with both magnetic flux cancellation (at the site of upflows only) derived from the Solar Dynamics Observatory's Helioseismic Magnetic Imager's line-of-sight magnetogram images, and a 30% mass influx at coronal heights. The incurred non-equilibrium structure of the cool loop leads to a catastrophic cooling event, with subsequent plasma evaporation indicating that the TR is the heating site. From the magnetic flux evolution, we conclude that magnetic reconnection between the footpoint and background field is responsible for the <span class="hlt">observed</span> fast TR plasma upflows.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19770038180&hterms=cuvette&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dcuvette','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19770038180&hterms=cuvette&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dcuvette"><span id="translatedtitle">The <span class="hlt">direct</span> <span class="hlt">observation</span> of solidification as a function of gravity level. [for space manufacturing</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnston, M. H.; Griner, C. S.</p> <p>1977-01-01</p> <p>A saturated solution of NH4Cl was solidified on earth at 1 g and in a suborbital rocket flight at .00001 g. In the 1 g experiments, macrosegregation caused by the gravitational acceleration was marked. Nucleation started at the cold walls after which dendrites and dendritic debris were swept into the center of the cuvette by convective fluid flow. Secondary dendrite arms were oriented toward the cold wall. When solidified in low g, only four nuclei grew to form the complete casting. There were no free floating crystals or visible dendrite remelting. The lack of fluid flow <span class="hlt">allowed</span> symmetrical dendrite growth into the fluid.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25525244','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25525244"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of closed magnetic flux trapped in the high-latitude magnetosphere.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fear, R C; Milan, S E; Maggiolo, R; Fazakerley, A N; Dandouras, I; Mende, S B</p> <p>2014-12-19</p> <p>The structure of Earth's magnetosphere is poorly understood when the interplanetary magnetic field is northward. Under this condition, uncharacteristically energetic plasma is <span class="hlt">observed</span> in the magnetotail lobes, which is not expected in the textbook model of the magnetosphere. Using satellite <span class="hlt">observations</span>, we show that these lobe plasma signatures occur on high-latitude magnetic field lines that have been closed by the fundamental plasma process of magnetic reconnection. Previously, it has been suggested that closed flux can become trapped in the lobe and that this plasma-trapping process could explain another poorly understood phenomenon: the presence of auroras at extremely high latitudes, called transpolar arcs. <span class="hlt">Observations</span> of the aurora at the same time as the lobe plasma signatures reveal the presence of a transpolar arc. The excellent correspondence between the transpolar arc and the trapped closed flux at high altitudes provides very strong evidence of the trapping mechanism as the cause of transpolar arcs. PMID:25525244</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/0912.3291v3','EPRINT'); return false;" href="http://arxiv.org/pdf/0912.3291v3"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Coherent Population Trapping in a Superconducting Artificial Atom</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>William R. Kelly; Zachary Dutton; John Schlafer; Bhaskar Mookerji; Thomas A. Ohki; Jeffrey S. Kline; David P. Pappas</p> <p>2010-03-10</p> <p>The phenomenon of Coherent Population Trapping (CPT) of an atom (or solid state "artificial atom"), and the associated effect of Electromagnetically Induced Transparency (EIT), are clear demonstrations of quantum interference due to coherence in multi-level quantum systems. We report <span class="hlt">observation</span> of CPT in a superconducting phase qubit by simultaneously driving two coherent transitions in a $\\Lambda$-type configuration, utilizing the three lowest lying levels of a local minimum of a phase qubit. We <span class="hlt">observe</span> $60(\\pm 7)%$ suppression of excited state population under conditions of CPT resonance. We present data and matching theoretical simulations showing the development of CPT in time. Finally, we used the <span class="hlt">observed</span> time dependence of the excited state population to characterize quantum dephasing times of the system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhRvL.105u8104C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhRvL.105u8104C"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Multiple Pathways of Single-Stranded DNA Stretching</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Wuen-Shiu; Chen, Wei-Hung; Chen, Zephan; Gooding, Ashton A.; Lin, Kuan-Jiuh; Kiang, Ching-Hwa</p> <p>2010-11-01</p> <p>We <span class="hlt">observed</span> multiple pathways of stretching single-stranded polydeoxynucleotides, poly(dA). Poly(dA) has been shown to undergo unique transitions under mechanical force, and such transitions were attributed to the stacking characteristics of poly(dA). Using single-molecule manipulation studies, we found that poly(dA) has two stretching pathways at high forces. The previously <span class="hlt">observed</span> pathway has a free energy that is less than what is expected of single-stranded DNA with a random sequence, indicating the existence of a novel conformation of poly(dA) at large extensions. We also <span class="hlt">observed</span> stepwise transitions between the two pathways by pulling the molecule with constant force, and found that the transitions are cooperative. These results suggest that the unique mechanical property of poly(dA) may play an important role in biological processes such as gene expression.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70046395','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70046395"><span id="translatedtitle">Instructions for <span class="hlt">observing</span> air temperature, humidity, and <span class="hlt">direction</span> and force of wind</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>U.S. Geological Survey</p> <p>1892-01-01</p> <p>Description of instruments.-The temperature and humidity of the air are obtained from the simultaneous <span class="hlt">observation</span> of a pair of mercurial thermometers termed the dry and the wet bulb. The air temperature is given by the dry-bulb thermometer, and the humidity is obtained from the combined readings of both. The wet-bulb thermometer differs from the dry-bulb thermometer only in having its bulb covered with thin muslin, which is wetted in pure water at each <span class="hlt">observation</span>.The two thermometers are fastened in a light metal 'or wooden frame. To this frame is to be attached a stout cord for the whirling of the thermometers, which is an essential part of every <span class="hlt">observation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMGC41E..05B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMGC41E..05B"><span id="translatedtitle"><span class="hlt">Direct</span> and remotely-sensed <span class="hlt">observations</span> of water vapor isotopes in the North American Monsoon domain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berkelhammer, M. B.; Langford, S.; Buenning, N. H.; Yoshimura, K.; Frankenberg, C.; Kaushik, A.; Noone, D. C.</p> <p>2012-12-01</p> <p>The climate models that make up the current IPCC ensemble do not accurately represent the predominant spatial and temporal features of the North American Monsoon (NAM) system. This leads to large uncertainty in predicting the response of the NAM to both anthropogenic and natural forcings. One method of diagnosing model deficiencies in capturing summertime precipitation patterns in the Southwestern US is to assess how the atmospheric moisture budget of a model compares to <span class="hlt">observed</span> budgets created using water isotope data. We present an analysis of continuous in situ ground and tower-based <span class="hlt">observations</span> of the isotopic composition of water vapor (?D and ?18O) and remotely-sensed satellite retrievals of the column-integrated isotopic composition of water vapor (?D) from the Greenhouse Gases <span class="hlt">Observing</span> Satellite over the southwestern US. The isotopic data capture a strong seasonal transition between winter and summer seasons, which is associated with a change between predominately northwesterly and southwesterly moisture sources. On synoptic timescales during the monsoon season, the isotopes also serve as a lucid tracer of "Gulf Surges" providing <span class="hlt">observational</span> confirmation on the importance of this moisture source; a finding that had previously been gleaned through "painted water" simulations and wind pattern analysis. While Gulf Surges are <span class="hlt">observable</span> from analysis of water vapor concentration alone, <span class="hlt">observations</span> of the isotopic composition of this phenomenon provides a unique capacity to trace the northerly extent of this moisture, which is difficult to discern from looking at non-isotopic humidity data alone. The new data also show that from a budgetary standpoint the significance of continental moisture fluxes (evaporation and transpiration) is quite large. This result therefore suggests that progress on modeling the NAM and ultimately in understandings its response to forcing cannot only be focused on large-scale SST and atmospheric circulation fields but also must better address the surface moisture dynamics and land-atmosphere coupling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/19997413','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/19997413"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of lateral photovoltaic effect in nano-metal-films.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yu, C Q; Wang, H; Xiao, S Q; Xia, Y X</p> <p>2009-11-23</p> <p>Lateral photovoltaic effect (LPE) <span class="hlt">observed</span> on the metal films is unusual because it violates a principle that the LPEs are always <span class="hlt">observed</span> on the surface of a semiconductor. Compared with early studies, we have realized an obvious metal film LPE in a metal-semiconductor (MS) structure. By further arguing with experimental results, this work also intensively elucidates many features of LPE which the early models never touched upon. All the data and analyses in this study indicate that metal side LPE in MS structure has some natural superiorities to the semiconductor side LPE and may open many exciting opportunities for realizing multifunctional devices. PMID:19997413</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007A%26A...464..107M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007A%26A...464..107M"><span id="translatedtitle"><span class="hlt">Direct</span> constraint on the distance of ?2 Velorum from AMBER/VLTI <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Millour, F.; Petrov, R. G.; Chesneau, O.; Bonneau, D.; Dessart, L.; Bechet, C.; Tallon-Bosc, I.; Tallon, M.; Thiébaut, E.; Vakili, F.; Malbet, F.; Mourard, D.; Antonelli, P.; Beckmann, U.; Bresson, Y.; Chelli, A.; Dugué, M.; Duvert, G.; Gennari, S.; Glück, L.; Kern, P.; Lagarde, S.; Le Coarer, E.; Lisi, F.; Perraut, K.; Puget, P.; Rantakyrö, F.; Robbe-Dubois, S.; Roussel, A.; Tatulli, E.; Weigelt, G.; Zins, G.; Accardo, M.; Acke, B.; Agabi, K.; Altariba, E.; Arezki, B.; Aristidi, E.; Baffa, C.; Behrend, J.; Blöcker, T.; Bonhomme, S.; Busoni, S.; Cassaing, F.; Clausse, J.-M.; Colin, J.; Connot, C.; Delboulbé, A.; Domiciano de Souza, A.; Driebe, T.; Feautrier, P.; Ferruzzi, D.; Forveille, T.; Fossat, E.; Foy, R.; Fraix-Burnet, D.; Gallardo, A.; Giani, E.; Gil, C.; Glentzlin, A.; Heiden, M.; Heininger, M.; Hernandez Utrera, O.; Hofmann, K.-H.; Kamm, D.; Kiekebusch, M.; Kraus, S.; Le Contel, D.; Le Contel, J.-M.; Lesourd, T.; Lopez, B.; Lopez, M.; Magnard, Y.; Marconi, A.; Mars, G.; Martinot-Lagarde, G.; Mathias, P.; Mège, P.; Monin, J.-L.; Mouillet, D.; Nussbaum, E.; Ohnaka, K.; Pacheco, J.; Perrier, C.; Rabbia, Y.; Rebattu, S.; Reynaud, F.; Richichi, A.; Robini, A.; Sacchettini, M.; Schertl, D.; Schöller, M.; Solscheid, W.; Spang, A.; Stee, P.; Stefanini, P.; Tasso, D.; Testi, L.; von der Lühe, O.; Valtier, J.-C.; Vannier, M.; Ventura, N.</p> <p>2007-03-01</p> <p>Context: Interferometry can provide spatially resolved <span class="hlt">observations</span> of massive star binary systems and their colliding winds, which thus far have been studied mostly with spatially unresolved <span class="hlt">observations</span>. Aims: We present the first AMBER/VLTI <span class="hlt">observations</span>, taken at orbital phase 0.32, of the Wolf-Rayet and O (WR+O) star binary system ?2 Velorum and use the interferometric <span class="hlt">observables</span> to constrain its properties. Methods: The AMBER/VLTI instrument was used with the telescopes UT2, UT3, and UT4 on baselines ranging from 46 m to 85 m. It delivered spectrally dispersed visibilities, as well as differential and closure phases, with a resolution R=1500 in the spectral band 1.95-2.17 ?m. We interpret these data in the context of a binary system with unresolved components, neglecting in a first approximation the wind-wind collision zone flux contribution. Results: Using WR- and O-star synthetic spectra, we show that the AMBER/VLTI <span class="hlt">observables</span> result primarily from the contribution of the individual components of the WR+O binary system. We discuss several interpretations of the residuals, and speculate on the detection of an additional continuum component, originating from the free-free emission associated with the wind-wind collision zone (WWCZ), and contributing at most to the <span class="hlt">observed</span> K-band flux at the 5% level. Based on the accurate spectroscopic orbit and the Hipparcos distance, the expected absolute separation and position angle at the time of <span class="hlt">observations</span> were 5.1±0.9 mas and 66±15°, respectively. However, using theoretical estimates for the spatial extent of both continuum and line emission from each component, we infer a separation of 3.62+0.11-0.30 mas and a position angle of 73+9-11°, compatible with the expected one. Our analysis thus implies that the binary system lies at a distance of 368+38-13 pc, in agreement with recent spectrophotometric estimates, but significantly larger than the Hipparcos value of 258+41-31 pc. Based on <span class="hlt">observations</span> collected at the European Southern Observatory, Paranal, Chile, within the guaranteed time programme 074.A-9025(A).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3742008','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3742008"><span id="translatedtitle"><span class="hlt">Direct</span> injection into the dorsal root ganglion: Technical, behavioral, and histological <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fischer, Gregory; Kostic, Sandra; Nakai, Hiroyuki; Park, Frank; Sapunar, Damir; Yu, Hongwei; Hogan, Quinn</p> <p>2013-01-01</p> <p><span class="hlt">Direct</span> injection of agents into the dorsal root ganglia (DRGs) offers the opportunity to manipulate sensory neuron function at a segmental level to explore pathophysiology of painful conditions. However, there is no described method that has been validated in detail for such injections in adult rats. We have found that 2 (µl of dye injected through a pulled glass pipette <span class="hlt">directly</span> into the distal DRG, exposed by a minimal foraminotomy, produces complete filling of the DRG with limited extension into the spinal roots. Injection into the spinal nerve required 3 µl to achieve comparable DRG filling, produced preferential spread into the ventral root, and was accompanied by substantial leakage of injected solution from the injection site. Injections into the sciatic nerve of volumes up to 10 (µl did not reach the DRG. Transient hypersensitivity to mechanical stimulation at threshold (von Frey) and noxious levels (pin) developed after 2 µl saline injection <span class="hlt">directly</span> into the DRG that was in part attributable to the surgical exposure procedure alone. Only minimal astrocyte activation in the spinal dorsal horn was evident after DRG saline injections. Injection of adeno-associated virus (AAV) vector conveying green fluorescent protein (GFP) transgene resulted in expression as soon as 1 day after injection into the DRG, including fibers in the spinal dorsal horn and columns. AAV injection into the DRG produced additional thermal hypersensitivity and withdrawal from the stroke of a brush and compromised motor performance. These findings demonstrate a method for selective injection of agents into single DRGs for anatomically restricted actions. PMID:21540055</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApPhL.107h3505T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApPhL.107h3505T"><span id="translatedtitle"><span class="hlt">Observation</span> and interpretation of energy efficient, diffuse <span class="hlt">direct</span> current glow discharge at atmospheric pressure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tang, Jie; Jiang, Weiman; Li, Jing; Wang, Yishan; Zhao, Wei; Duan, Yixiang</p> <p>2015-08-01</p> <p>A diffuse <span class="hlt">direct</span>-current glow discharge was realized with low energy consumption and high energy utilization efficiency at atmospheric pressure. The formation of diffuse discharge was demonstrated by examining and comparing the electrical properties and optical emissions of plasmas. In combination with theoretical derivation and calculation, we draw guidelines that appearance of nitrogen ions at low electron density is crucial to enhance the ambipolar diffusion for the expansion of discharge channel and the increasing ambipolar diffusion near the cathode plays a key role in the onset of diffuse discharge. An individual-discharge-channel expansion model is proposed to explain the diffuse discharge formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://crystal.che.ncsu.edu/pdfs/la_KVfoam.pdf','EPRINT'); return false;" href="http://crystal.che.ncsu.edu/pdfs/la_KVfoam.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of the Dynamics of Latex Particles Confined inside Thinning Water-Air Films</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Velev, Orlin D.</p> <p></p> <p>in thinning foam films was investigated by microscopic interferometric <span class="hlt">observation</span>. The behavior surfactant. After the foam films are opened and closed a few times, a layer of particles simultaneously adsorbed to the two interfaces is formed, which sterically inhibits any further film opening and thinning</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRC..119.5934C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRC..119.5934C"><span id="translatedtitle"><span class="hlt">Direct</span> velocity <span class="hlt">observations</span> of volume flux between Iceland and the Shetland Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Childers, Katelin H.; Flagg, Charles N.; Rossby, Thomas</p> <p>2014-09-01</p> <p>Atlantic Waters flowing northward into the Nordic Seas are important for their role as an early indicator of changes to deepwater formation. As such, this requires a fundamental understanding of the pathways and volume fluxes through the primary passageways from the Atlantic into the Nordic Seas. A mean annual volume transport of 6.1 ± 0.3 Sv was <span class="hlt">observed</span> flowing in above the ?t = 27.8 isopycnal (a proxy for the lower limit of Atlantic Water depth), through the Faroe Shetland Channel (FSC) and over the Iceland Faroes Ridge (IFR) from March 2008 to June 2012, using repeat velocity sections obtained from a vessel mounted Acoustic Doppler Current Profiler (ADCP). A new vessel route has expanded the spatial coverage of FSC <span class="hlt">observations</span> and reveals a difference in average inflow transport, which most likely results from an interannual variation in the total transport through the FSC, which in turn is tied to a weakening of the southerly flow over the western slope of the channel. This interannual variability has increased the mean transport through the FSC from 0.9 Sv <span class="hlt">observed</span> over the first 2 years of this program by Rossby and Flagg (2012) to a 4.5 year mean of 1.7 ± 0.2 Sv, which emphasizes the importance of knowing the flow along the Faroese shelf. Interannual fluctuations in transport <span class="hlt">observed</span> over the IFR are related to the width of the inflow over the Faroese half of the ridge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1501.04999.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1501.04999.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observations</span> of Plasma Upflows and Condensation in a Catastrophically Cooling Solar Transition Region Looop</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Orange, N B; Oluseyi, H M; Hesterly, K; Patel, M; Champey, P R</p> <p>2015-01-01</p> <p>Minimal <span class="hlt">observational</span> evidence exists for fast transition region (TR) upflows in the presence of cool loops. <span class="hlt">Observations</span> of such occurrences challenge notions of standard solar atmospheric heating models, as well as their description of bright TR emission. Using the {\\it EUV Imaging Spectrometer} (EIS) onboard {\\it Hinode}, we <span class="hlt">observe</span> fast upflows ($v_\\lambda$\\,$\\le$\\,$-$10 km s$^{-1}$) over multiple TR temperatures (5.8\\,$\\le$\\,$\\log T$\\,$\\le$ 6.0) at the footpoint sites of a cool loop ($\\log T$\\,$\\le$\\,6.0). Prior to cool loop energizing, asymmetric flows of $+$\\,5 km s$^{-1}$ and $-$\\,60 km s$^{-1}$ are <span class="hlt">observed</span> at footpoint sites. These flows speeds and patterns occur simultaneously with both magnetic flux cancellation (at site of upflows only) derived from the {\\it Solar Dynamics Observatory}'s (SDOs) { \\it Helioseismic Magnetic Imager}'s (HMI) line-of-sight magnetogram images, and a 30\\% mass in-flux at coronal heights. The incurred non-equilibrium structure of the cool loop leads to a catastrophic coo...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=sedentary&pg=3&id=EJ1037033','ERIC'); return false;" href="http://eric.ed.gov/?q=sedentary&pg=3&id=EJ1037033"><span id="translatedtitle"><span class="hlt">Directly</span> <span class="hlt">Observed</span> Physical Activity among 3-Year-Olds in Finnish Childcare</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Soini, Anne; Villberg, Jari; Sääkslahti, Arja; Gubbels, Jessica; Mehtälä, Anette; Kettunen, Tarja; Poskiparta, Marita</p> <p>2014-01-01</p> <p>The main purpose of the study was to determine 3-year-olds' physical activity levels and how these vary across season, gender, time of day, location, and the physical and social environment in childcare settings in Finland. A modified version of the <span class="hlt">Observational</span> System for Recording Physical Activity in Children-Preschool (OSRAC-P) was used…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.physics.ucdavis.edu/fadleygroup/CMRPRL.reprint.pdf','EPRINT'); return false;" href="http://www.physics.ucdavis.edu/fadleygroup/CMRPRL.reprint.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of High-Temperature Polaronic Behavior in Colossal Magnetoresistive Manganites</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Fadley, Charles</p> <p></p> <p>on crossing the Curie temperature, including charge localization on and spin-moment increase of Mn, together of polaron for- mation. These results suggest that the presence of polar- ons above the Curie temperature (TCDirect <span class="hlt">Observation</span> of High-Temperature Polaronic Behavior in Colossal Magnetoresistive Manganites N</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023335','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023335"><span id="translatedtitle"><span class="hlt">Observations</span> of bi-<span class="hlt">directional</span> leader development in a triggered lightning flash</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Laroche, P.; Idone, V.; Eybert-Berard, A.; Barret, L.</p> <p>1991-01-01</p> <p><span class="hlt">Observations</span> of a modified form of rocket triggered lightning are described. A flash triggered during the summer of 1989 is studied as part of an effort to model bidirectional discharge. It is suggested that the altitude triggering technique provides a realistic means of studying the attachment process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EPSC...10..505H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EPSC...10..505H"><span id="translatedtitle">Two radars for AIM mission: A <span class="hlt">direct</span> <span class="hlt">observation</span> of the asteroid's structure from deep interior to regolith</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Herique, A.; Ciarletti, V.</p> <p>2015-10-01</p> <p>Our knowledge of the internal structure of asteroids is, so far, indirect - relying entirely on inferences from remote sensing <span class="hlt">observations</span> of the surface, and theoretical modeling. What are the bulk properties of the regolith and deep interior? And what are the physical processes that shape their internal structures? <span class="hlt">Direct</span> measurements are needed to provide answers that will <span class="hlt">directly</span> improve our ability to understand and model the mechanisms driving Near Earth Asteroids (NEA) for the benefit of science as well as for planetary defense or exploration. Radar tomography is the only technique to characterize internal structure from decimetric scale to global scale. This paper reviews the benefits of <span class="hlt">direct</span> measurement of the asteroid interior. Then the radar concepts for both deep interior and shallow subsurface are presented and the radar payload proposed for the AIDA/AIM mission is outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MMTA...46.4886S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MMTA...46.4886S"><span id="translatedtitle">Simulation of Channel Segregation During <span class="hlt">Directional</span> Solidification of In—75 wt pct Ga. Qualitative Comparison with In Situ <span class="hlt">Observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saad, Ali; Gandin, Charles-André; Bellet, Michel; Shevchenko, Natalia; Eckert, Sven</p> <p>2015-11-01</p> <p>Freckles are common defects in industrial casting. They result from thermosolutal convection due to buoyancy forces generated from density variations in the liquid. The present paper proposes a numerical analysis for the formation of channel segregation using the three-dimensional (3D) cellular automaton (CA)—finite element (FE) model. The model integrates kinetics laws for the nucleation and growth of a microstructure with the solution of the conservation equations for the casting, while introducing an intermediate modeling scale for a <span class="hlt">direct</span> representation of the envelope of the dendritic grains. <span class="hlt">Directional</span> solidification of a cuboid cell is studied. Its geometry, the alloy chosen as well as the process parameters are inspired from experimental <span class="hlt">observations</span> recently reported in the literature. Snapshots of the convective pattern, the solute distribution, and the morphology of the growth front are qualitatively compared. Similitudes are found when considering the coupled 3D CAFE simulations. Limitations of the model to reach <span class="hlt">direct</span> simulation of the experiments are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApPhL.107k1105R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApPhL.107k1105R"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of a resolvable spin separation in the spin Hall effect of light at an air-glass interface</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ren, Jin-Li; Wang, Bo; Xiao, Yun-Feng; Gong, Qihuang; Li, Yan</p> <p>2015-09-01</p> <p>We theoretically and experimentally demonstrate that it is possible to <span class="hlt">directly</span> <span class="hlt">observe</span> the resolvable spin separation in the spin Hall effect of light at an air-glass interface by choosing optimal parameters. When a P-polarized light with a beam waist of 10 ?m is incident around Brewster's angle, the two spin components of the reflected beam can be completely separated by eliminating the influence of the in-plane wavevector spread. This not only obviously reveals the strong impacts of the polarization state, the incident angle, the beam waist, and the in-plane wavevector spread, but also intuitively visualizes the <span class="hlt">observation</span> of the spin Hall effect of light.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1221377','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1221377"><span id="translatedtitle">Transmission Electron Microscope In Situ Straining Technique to <span class="hlt">Directly</span> <span class="hlt">Observe</span> Defects and Interfaces During Deformation in Magnesium</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Morrow, Benjamin M.; Cerreta, E. K.; McCabe, R. J.; Tomé, C. N.</p> <p>2015-05-14</p> <p>In-situ straining was used to study deformation behavior of hexagonal close-packed (hcp) metals.Twinning and dislocation motion, both essential to plasticity in hcp materials, were <span class="hlt">observed</span>.Typically, these processes are characterized post-mortem by examining remnant microstructural features after straining has occurred. By imposing deformation during imaging, <span class="hlt">direct</span> <span class="hlt">observation</span> of active deformation mechanisms is possible. This work focuses on straining of structural metals in a transmission electron microscope (TEM), and a recently developed technique that utilizes familiar procedures and equipment to increase ease of experiments. In-situ straining in a TEM presents several advantages over conventional post-mortem characterization, most notably time-resolution of deformation and streamlined identification of active deformation mechanisms. Drawbacks to the technique and applicability to other studies are also addressed. In-situ straining is used to study twin boundary motion in hcp magnesium. A {101¯2} twin was <span class="hlt">observed</span> during tensile and compressive loading. Twin-dislocation interactions are <span class="hlt">directly</span> <span class="hlt">observed</span>. Notably, dislocations are <span class="hlt">observed</span> to remain mobile, even after multiple interactions with twin boundaries, a result which suggests that Basinki’s dislocation transformation mechanism by twinning is not present in hcp metals. The coupling of in-situ straining with traditional post-mortem characterization yields more detailed information about material behavior during deformation than either technique alone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JOM....67h1721M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JOM....67h1721M"><span id="translatedtitle">Transmission Electron Microscope In Situ Straining Technique to <span class="hlt">Directly</span> <span class="hlt">Observe</span> Defects and Interfaces During Deformation in Magnesium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morrow, B. M.; Cerreta, E. K.; McCabe, R. J.; Tomé, C. N.</p> <p>2015-08-01</p> <p>In situ straining was used to study deformation behavior of hexagonal close-packed (hcp) metals. Twinning and dislocation motion, both essential to plasticity in hcp materials, were <span class="hlt">observed</span>. Typically, these processes are characterized postmortem by examining remnant microstructural features after straining has occurred. By imposing deformation during imaging, <span class="hlt">direct</span> <span class="hlt">observation</span> of active deformation mechanisms is possible. This work focuses on straining of structural metals in a transmission electron microscope (TEM), and a recently developed technique that utilizes familiar procedures and equipment to increase ease of experiments. In situ straining in a TEM presents several advantages over conventional postmortem characterization, most notably time resolution of deformation and streamlined identification of active deformation mechanisms. Drawbacks to the technique and applicability to other studies are also addressed. In situ straining is used to study twin boundary motion in hcp magnesium. A twin was <span class="hlt">observed</span> during tensile and compressive loading. Twin-dislocation interactions are <span class="hlt">directly</span> <span class="hlt">observed</span>. Notably, dislocations are <span class="hlt">observed</span> to remain mobile, even after multiple interactions with twin boundaries; this result suggests that Basinki's dislocation transformation mechanism by twinning is not present in hcp metals. The coupling of in situ straining with traditional postmortem characterization yields more detailed information about material behavior during deformation than either technique alone.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1221377-transmission-electron-microscope-situ-straining-technique-directly-observe-defects-interfaces-during-deformation-magnesium','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1221377-transmission-electron-microscope-situ-straining-technique-directly-observe-defects-interfaces-during-deformation-magnesium"><span id="translatedtitle">Transmission Electron Microscope In Situ Straining Technique to <span class="hlt">Directly</span> <span class="hlt">Observe</span> Defects and Interfaces During Deformation in Magnesium</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Morrow, Benjamin M.; Cerreta, E. K.; McCabe, R. J.; Tomé, C. N.</p> <p>2015-05-14</p> <p>In-situ straining was used to study deformation behavior of hexagonal close-packed (hcp) metals.Twinning and dislocation motion, both essential to plasticity in hcp materials, were <span class="hlt">observed</span>.Typically, these processes are characterized post-mortem by examining remnant microstructural features after straining has occurred. By imposing deformation during imaging, <span class="hlt">direct</span> <span class="hlt">observation</span> of active deformation mechanisms is possible. This work focuses on straining of structural metals in a transmission electron microscope (TEM), and a recently developed technique that utilizes familiar procedures and equipment to increase ease of experiments. In-situ straining in a TEM presents several advantages over conventional post-mortem characterization, most notably time-resolution of deformation andmore »streamlined identification of active deformation mechanisms. Drawbacks to the technique and applicability to other studies are also addressed. In-situ straining is used to study twin boundary motion in hcp magnesium. A {101¯2} twin was <span class="hlt">observed</span> during tensile and compressive loading. Twin-dislocation interactions are <span class="hlt">directly</span> <span class="hlt">observed</span>. Notably, dislocations are <span class="hlt">observed</span> to remain mobile, even after multiple interactions with twin boundaries, a result which suggests that Basinki’s dislocation transformation mechanism by twinning is not present in hcp metals. The coupling of in-situ straining with traditional post-mortem characterization yields more detailed information about material behavior during deformation than either technique alone.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4674681','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4674681"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of titanium-centered octahedra in titanium–antimony–tellurium phase-change material</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rao, Feng; Song, Zhitang; Cheng, Yan; Liu, Xiaosong; Xia, Mengjiao; Li, Wei; Ding, Keyuan; Feng, Xuefei; Zhu, Min; Feng, Songlin</p> <p>2015-01-01</p> <p>Phase-change memory based on Ti0.4Sb2Te3 material has one order of magnitude faster Set speed and as low as one-fifth of the Reset energy compared with the conventional Ge2Sb2Te5 based device. However, the phase-transition mechanism of the Ti0.4Sb2Te3 material remains inconclusive due to the lack of <span class="hlt">direct</span> experimental evidence. Here we report a <span class="hlt">direct</span> atom-by-atom chemical identification of titanium-centered octahedra in crystalline Ti0.4Sb2Te3 material with a state-of-the-art atomic mapping technology. Further, by using soft X-ray absorption spectroscopy and density function theory simulations, we identify in amorphous Ti0.4Sb2Te3 the titanium atoms preferably maintain the octahedral configuration. Our work may pave the way to more thorough understanding and tailoring of the nature of the Ti–Sb–Te material, for promoting the development of dynamic random access memory-like phase-change memory as an emerging storage-class memory to reform current memory hierarchy. PMID:26610374</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21409973','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21409973"><span id="translatedtitle">Connecting the <span class="hlt">direct</span> detection of dark matter with <span class="hlt">observation</span> of sparticles at the LHC</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Feldman, Daniel; Liu Zuowei; Nath, Pran</p> <p>2010-05-01</p> <p>An analysis is given connecting event rates for the <span class="hlt">direct</span> detection of neutralino dark matter with the possible signatures of supersymmetry at the LHC. It is shown that if an effect is seen in the <span class="hlt">direct</span> detection experiments at a level of O(10{sup -44}) cm{sup 2} for the neutralino-proton cross section, then within the minimal supergravity grand unified model the next heavier particle above the neutralino is either a stau, a chargino, or a CP odd/CP even (A/H) Higgs boson. Further, the collider analysis shows that models with a neutralino-proton cross section at the level of (1-5)x10{sup -44} cm{sup 2} could be probed with as little as 1 fb{sup -1} of integrated luminosity at the LHC at {radical}(s)=7, 10 TeV. The most recent limit from the five tower CDMS II result on weakly interacting massive particle-nucleon cross section is discussed in this context. It is argued that the conclusions of the analysis given here are more broadly applicable with inclusion of nonuniversalities in the supergravity grand unified models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26610374','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26610374"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of titanium-centered octahedra in titanium-antimony-tellurium phase-change material.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rao, Feng; Song, Zhitang; Cheng, Yan; Liu, Xiaosong; Xia, Mengjiao; Li, Wei; Ding, Keyuan; Feng, Xuefei; Zhu, Min; Feng, Songlin</p> <p>2015-01-01</p> <p>Phase-change memory based on Ti0.4Sb2Te3 material has one order of magnitude faster Set speed and as low as one-fifth of the Reset energy compared with the conventional Ge2Sb2Te5 based device. However, the phase-transition mechanism of the Ti0.4Sb2Te3 material remains inconclusive due to the lack of <span class="hlt">direct</span> experimental evidence. Here we report a <span class="hlt">direct</span> atom-by-atom chemical identification of titanium-centered octahedra in crystalline Ti0.4Sb2Te3 material with a state-of-the-art atomic mapping technology. Further, by using soft X-ray absorption spectroscopy and density function theory simulations, we identify in amorphous Ti0.4Sb2Te3 the titanium atoms preferably maintain the octahedral configuration. Our work may pave the way to more thorough understanding and tailoring of the nature of the Ti-Sb-Te material, for promoting the development of dynamic random access memory-like phase-change memory as an emerging storage-class memory to reform current memory hierarchy. PMID:26610374</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1101.2297v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1101.2297v1"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of stress accumulation and relaxation in small bundles of superconducting vortices in tungsten thin-films</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>I. Guillamon; H. Suderow; S. Vieira; J. Sese; R. Cordoba; J. M. De Teresa; M. R. Ibarra</p> <p>2011-01-12</p> <p>We study the behavior of bundles of superconducting vortices when increasing the magnetic field using scanning tunneling microscopy and spectroscopy (STM/S) at 100 mK. Pinning centers are given by features on the surface corrugation. We find strong net vortex motion in a bundle towards a well defined <span class="hlt">direction</span>. We <span class="hlt">observe</span> continuos changes of the vortex arrangements, and identify small displacements, which stress and deform the vortex bundle, separated by larger re-arrangements or avalanches, which release accumulated stress.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.physics.montana.edu/eam/publications/2006_JCG292_395.pdf','EPRINT'); return false;" href="http://www.physics.montana.edu/eam/publications/2006_JCG292_395.pdf"><span id="translatedtitle">Journal of Crystal Growth 292 (2006) 395398 <span class="hlt">Direct</span> <span class="hlt">observation</span> of ferroelectric domains and phases in (0 0 1)-cut</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p>2006-01-01</p> <p>Journal of Crystal Growth 292 (2006) 395­398 <span class="hlt">Direct</span> <span class="hlt">observation</span> of ferroelectric domains and phases in (0 0 1)-cut Pb(Mg1/3Nb2/3)1ÀxTixO3 single crystals under electric-field poling R.R. Chiena,Ã, V. Hugo.33O3 (PMNT33%) single crystal has been performed by polarizing microscopy. A hysteresis loop</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22304459','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22304459"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the topological charge of a terahertz vortex beam generated by a Tsurupica spiral phase plate</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Miyamoto, K.; Suizu, K.; Akiba, T.; Omatsu, T.</p> <p>2014-06-30</p> <p>A terahertz (THz) spiral phase plate with high transmission (>90% after Fresnel correction) and low dispersion has been developed based on the Tsurupica olefin polymer. <span class="hlt">Direct</span> <span class="hlt">observations</span> of the topological charge (both magnitude and sign) of a THz vortex beam are performed by using a THz camera with tilted lens focusing and radial defect introduction. The vortex outputs with a topological charge of ±1 (or ±2) are obtained at a frequency of 2 (or 4) THz.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.H42E..05D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.H42E..05D"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of flow path evolution during reactive transport in porous media using clinical nuclear imaging tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Druhan, J. L.; Finsterle, S.; Vandehey, N. T.; Boutchko, R.; O'Neil, J.; Moses, W. W.; Nico, P. S.</p> <p>2012-12-01</p> <p>Changes in the physical structure of a porous medium associated with heterogeneous reactivity are extremely difficult to <span class="hlt">observe</span> <span class="hlt">directly</span>. We require the ability to monitor, quantify and predict these changes in order to optimize contaminant sequestration and remediation strategies, develop carbon storage methods and preserve groundwater resources. Field-scale detection of chemically induced permeability alteration is often accomplished by multiple hydrogeophysical <span class="hlt">observations</span> and pumping tests, whereas <span class="hlt">direct</span> analysis of the structural changes in a porous medium are limited to small sample sizes that do not capture the range of length scales describing heterogeneity. Here we present a novel application of medical imaging techniques to <span class="hlt">directly</span> <span class="hlt">observe</span> variations in flow field structure associated with mineral precipitation in real time. We use a Single Photon Emission Computed Tomography (SPECT) scanner to <span class="hlt">observe</span> the movement of a conservative 99mTc-DTPA tracer introduced to a through-flowing column of packed sediment recovered from the Old Rifle aquifer in Western Colorado. Nine individual imaging studies were carried out over the course of 112 days of continuous flow in the 30 cm long, 10 cm diameter column. During this time, organic carbon was supplied to the influent, leading to microbially mediated reduction of Fe(III) (hyrdo)oxides and sulfate. Permeability reduction associated with this reactivity is known to occur as a result of biomass accumulation and precipitation of FeS and carbonate minerals. The nine imaging datasets each yielded intensity values over a 24 hour period at a resolution of 4.42 mm3. These images were corrected for decay and attenuation to produce 4D datasets <span class="hlt">directly</span> proportional to Tc-DTPA concentration. These data provide a highly accurate <span class="hlt">observation</span> of the flow field during each imaging study, and are used to assign property values to the elements of a geostatistical model using the iTOUGH2 code. Permeability distributions obtained from these inverse techniques demonstrate substantial changes in flow field structure over the 112 days of continuous reactive flow, providing a <span class="hlt">direct</span> <span class="hlt">observation</span> of the coupling between heterogeneous reactivity and variable permeability at a scale relevant to field applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22949690','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22949690"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of hydrogen atom dynamics and interactions by ultrahigh resolution neutron protein crystallography.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Julian C-H; Hanson, B Leif; Fisher, S Zoë; Langan, Paul; Kovalevsky, Andrey Y</p> <p>2012-09-18</p> <p>The 1.1 ?, ultrahigh resolution neutron structure of hydrogen/deuterium (H/D) exchanged crambin is reported. Two hundred ninety-nine out of 315, or 94.9%, of the hydrogen atom positions in the protein have been experimentally derived and resolved through nuclear density maps. A number of unconventional interactions are clearly defined, including a potential O?H…? interaction between a water molecule and the aromatic ring of residue Y44, as well as a number of potential C?H…O hydrogen bonds. Hydrogen bonding networks that are ambiguous in the 0.85 ? ultrahigh resolution X-ray structure can be resolved by accurate orientation of water molecules. Furthermore, the high resolution of the reported structure has <span class="hlt">allowed</span> for the anisotropic description of 36 deuterium atoms in the protein. The visibility of hydrogen and deuterium atoms in the nuclear density maps is discussed in relation to the resolution of the neutron data. PMID:22949690</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4327544','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4327544"><span id="translatedtitle"><span class="hlt">Observation</span> of <span class="hlt">directly</span> interacting coherent two-level systems in an amorphous material</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lisenfeld, Jürgen; Grabovskij, Grigorij J.; Müller, Clemens; Cole, Jared H.; Weiss, Georg; Ustinov, Alexey V.</p> <p>2015-01-01</p> <p>Parasitic two-level tunnelling systems originating from structural material defects affect the functionality of various microfabricated devices by acting as a source of noise. In particular, superconducting quantum bits may be sensitive to even single defects when these reside in the tunnel barrier of the qubit’s Josephson junctions, and this can be exploited to <span class="hlt">observe</span> and manipulate the quantum states of individual tunnelling systems. Here, we detect and fully characterize a system of two strongly interacting defects using a novel technique for high-resolution spectroscopy. Mutual defect coupling has been conjectured to explain various anomalies of glasses, and was recently suggested as the origin of low-frequency noise in superconducting devices. Our study provides conclusive evidence of defect interactions with full access to the individual constituents, demonstrating the potential of superconducting qubits for studying material defects. All our <span class="hlt">observations</span> are consistent with the assumption that defects are generated by atomic tunnelling. PMID:25652611</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25754895','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25754895"><span id="translatedtitle">Representativeness of <span class="hlt">direct</span> <span class="hlt">observations</span> selected using a work-sampling equation.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sharp, Rebecca A; Mudford, Oliver C; Elliffe, Douglas</p> <p>2015-01-01</p> <p>Deciding on appropriate sampling to obtain representative samples of behavior is important but not straightforward, because the relative duration of the target behavior may affect its <span class="hlt">observation</span> in a given sampling interval. Work-sampling methods, which offer a way to adjust the frequency of sampling according to a priori or ongoing estimates of the behavior to achieve a preselected level of representativeness, may provide a solution. Full-week <span class="hlt">observations</span> of 7 behaviors were conducted for 3 students with autism spectrum disorder and intellectual disabilities. Work-sampling methods were used to select momentary time samples from the full time-of-interest, which produced representative samples. However, work sampling required impractically high numbers of time samples to obtain representative samples. More practical momentary time samples produced less representative samples, particularly for low-duration behaviors. The utility and limits of work-sampling methods for applied behavior analysis are discussed. PMID:25754895</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4643781','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4643781"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of an attosecond electron wave packet in a nitrogen molecule</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Okino, Tomoya; Furukawa, Yusuke; Nabekawa, Yasuo; Miyabe, Shungo; Amani Eilanlou, A.; Takahashi, Eiji J.; Yamanouchi, Kaoru; Midorikawa, Katsumi</p> <p>2015-01-01</p> <p>Capturing electron motion in a molecule is the basis of understanding or steering chemical reactions. Nonlinear Fourier transform spectroscopy using an attosecond-pump/attosecond-probe technique is used to <span class="hlt">observe</span> an attosecond electron wave packet in a nitrogen molecule in real time. The 500-as electronic motion between two bound electronic states in a nitrogen molecule is captured by measuring the fragment ions with the same kinetic energy generated in sequential two-photon dissociative ionization processes. The temporal evolution of electronic coherence originating from various electronic states is visualized via the fragment ions appearing after irradiation of the probe pulse. This <span class="hlt">observation</span> of an attosecond molecular electron wave packet is a critical step in understanding coupled nuclear and electron motion in polyatomic and biological molecules to explore attochemistry. PMID:26601262</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26601262','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26601262"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of an attosecond electron wave packet in a nitrogen molecule.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Okino, Tomoya; Furukawa, Yusuke; Nabekawa, Yasuo; Miyabe, Shungo; Amani Eilanlou, A; Takahashi, Eiji J; Yamanouchi, Kaoru; Midorikawa, Katsumi</p> <p>2015-09-01</p> <p>Capturing electron motion in a molecule is the basis of understanding or steering chemical reactions. Nonlinear Fourier transform spectroscopy using an attosecond-pump/attosecond-probe technique is used to <span class="hlt">observe</span> an attosecond electron wave packet in a nitrogen molecule in real time. The 500-as electronic motion between two bound electronic states in a nitrogen molecule is captured by measuring the fragment ions with the same kinetic energy generated in sequential two-photon dissociative ionization processes. The temporal evolution of electronic coherence originating from various electronic states is visualized via the fragment ions appearing after irradiation of the probe pulse. This <span class="hlt">observation</span> of an attosecond molecular electron wave packet is a critical step in understanding coupled nuclear and electron motion in polyatomic and biological molecules to explore attochemistry. PMID:26601262</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4267372','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4267372"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of prefreezing at the interface melt–solid in polymer crystallization</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Löhmann, Ann-Kristin; Henze, Thomas; Thurn-Albrecht, Thomas</p> <p>2014-01-01</p> <p>Crystallization is almost always initiated at an interface to a solid. This <span class="hlt">observation</span> is classically explained by the assumption of a reduced barrier for crystal nucleation at the interface. However, an interface can also induce crystallization by prefreezing (i.e., the formation of a crystalline layer that is already stable above the bulk melting temperature). We present an atomic force microscopy (AFM)-based in situ <span class="hlt">observation</span> of a prefreezing process at the interface of a polymeric model system and a crystalline solid. Explicitly, we show an interfacial ordered layer that forms well above the bulk melting temperature with thickness that increases on approaching melt–solid coexistence. Below the melting temperature, the ordered layer initiates crystal growth into the bulk, leading to an oriented, homogeneous semicrystalline structure. PMID:25422447</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhRvB..77n4411T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhRvB..77n4411T"><span id="translatedtitle">Evidence of L10 chemical order in CoPt nanoclusters: <span class="hlt">Direct</span> <span class="hlt">observation</span> and magnetic signature</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tournus, Florent; Tamion, Alexandre; Blanc, Nils; Hannour, Abdelkrim; Bardotti, Laurent; Prével, Brigitte; Ohresser, Philippe; Bonet, Edgar; Epicier, Thierry; Dupuis, Véronique</p> <p>2008-04-01</p> <p>We report the synthesis and characterization of well-defined CoPt clusters with a mean diameter of 3 nm, produced in ultrahigh vacuum conditions following a physical route. Samples made of diluted layers of CoPt clusters embedded in amorphous carbon have been studied by transmission electron microscopy. High-resolution <span class="hlt">observations</span> have revealed the appearance of L10 chemical order upon annealing, even for clusters with a 2 nm diameter, without cluster coalescence. The magnetic properties of both chemically disordered and ordered CoPt clusters embedded in amorphous carbon have then been measured by x-ray magnetic circular dichroism and superconducting quantum interference device magnetometry. Despite a striking change of the Co magnetic moment, the magnetic anisotropy of chemically ordered nanoparticles increases, with respect to the chemically disordered A1 phase, in much lower proportions than what is <span class="hlt">observed</span> for the bulk.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AcSpA.149...54L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AcSpA.149...54L"><span id="translatedtitle">Ultrafast imaging of electronic relaxation in n-propylbenzene: <span class="hlt">Direct</span> <span class="hlt">observation</span> of intermediate state</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Yuzhu; Gerber, Thomas; Radi, Peter; Knopp, Gregor</p> <p>2015-10-01</p> <p>The ultrafast dynamics of the second singlet electronically excited state (S2) in n-propylbenzene has been investigated by femtosecond time-resolved photoelectron imaging coupled with photofragmentation spectroscopy. The intermediate state for the deactivation of the S2 state is <span class="hlt">observed</span> by transient photoelectron kinetic energy distributions and photoelectron angular distributions. An ultrafast electronic relaxation process on timescale of the fitted ?50 fs was <span class="hlt">observed</span> in the S2 state by time-resolved photoelectron imaging and it is attributed to the S1 ? S2 internal conversion (IC). The time constant of 1.23 (±0.2) ps is determined for the further deactivation of the intermediate S1 state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22408268','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22408268"><span id="translatedtitle"><span class="hlt">Observation</span> of dust torus with poloidal rotation in <span class="hlt">direct</span> current glow discharge plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kaur, Manjit Bose, Sayak; Chattopadhyay, P. K. Sharma, Devendra; Ghosh, J.; Saxena, Y. C.</p> <p>2015-03-15</p> <p><span class="hlt">Observation</span> of dust cloud rotation in parallel-plate DC glow discharge plasma is reported here. The experiments are carried out at high pressures (?130?Pa) with a metallic ring placed on the lower electrode (cathode). The dust cloud rotates poloidally in the vertical plane near the cathode surface. This structure is continuous toroidally. Absence of magnetic field rules out the possibility of E?×?B induced ion flow as the cause of dust rotation. The dust rotational structures exist even with water cooled cathode. Therefore, temperature gradient driven mechanisms, such as thermophoretic force, thermal creep flow, and free convection cannot be causing the <span class="hlt">observed</span> dust rotation. Langmuir probe measurement reveals the existence of a sharp density gradient near the location of the rotating dust cloud. The gradient in the density, giving rise to a gradient in the ion drag force, has been identified as the principal cause behind the rotation of dust particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21175645','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21175645"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the birth of a nanocrystalline nucleus in an amorphous matrix</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rauf, Ijaz A.</p> <p>2008-10-06</p> <p>Nucleation of crystals within an amorphous phase can be induced using electron beam irradiation in an electron microscope. In contrast to generally believed two-step phase transformation involving nucleation and growth, we <span class="hlt">observe</span> a three-step transformation: a two-step nucleation stage followed by the growth process. The two steps in the nucleation stage are: the formation of a basic crystalline skeleton followed by the diffusion of excess defects to the periphery of the crystalline skeleton.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/951519','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/951519"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of spin-like reaction fronts in planar energetic multilayer foils.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Adams, David Price; Hodges, V. Carter; Jones, Eric D., Jr.; McDonald, Joel Patrick</p> <p>2008-10-01</p> <p>Propagating reactions in initially planar cobalt/aluminum exothermic multilayer foils have been investigated using high-speed digital photography. Real-time <span class="hlt">observations</span> of reactions indicate that unsteady (spinlike) reaction propagation leads to the formation of highly periodic surface morphologies with length scales ranging from 1 {micro}m to 1 mm. The characteristics of propagating spinlike reactions and corresponding reacted foil morphologies depend on the bilayer thickness of multilayer foils.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/2723815','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/2723815"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of molecular images of lanthanide phthalocyanines: III. Structural defects.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, W P; Kuo, K H; Dorset, D L; Hou, Y F; Ni, J Z</p> <p>1989-04-01</p> <p>The crystal imperfections in thin films of lanthanide phthalocyanines (LnPc2H, Ln = Nd, Tb, Er, Tm, Yb, and Lu) grown expitaxially on KCl have been <span class="hlt">observed</span> by molecular imaging. Grain and twin boundaries, stacking faults, point defects, vacancies, mosaic structures, and sometimes even some amorphous islands exist in the well-crystallized specimens. Combined with the results reported earlier, the packing characteristics of planar LnPc2H molecules can be well understood. PMID:2723815</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1488471','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1488471"><span id="translatedtitle">Nature of the clinical difficulties of first-year family medicine residents under <span class="hlt">direct</span> <span class="hlt">observation</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Beaumier, A; Bordage, G; Saucier, D; Turgeon, J</p> <p>1992-01-01</p> <p>OBJECTIVE: To determine and classify the difficulties of first-year family medicine residents <span class="hlt">observed</span> during clinical interviews. DESIGN: Retrospective, descriptive study. SETTING: Family practice unit at a teaching hospital. PARTICIPANTS: Forty-seven of the 56 first-year family medicine residents during their 2-month compulsory rotation in ambulatory family medicine, between July 1983 and December 1988, and 4 physicians who supervised the residents. MAIN OUTCOME MEASURE: The residents' difficulties noted on the <span class="hlt">observation</span> forms. MAIN RESULTS: A total of 1500 difficulties were <span class="hlt">observed</span> during 194 interviews, an average of 7.7 (standard deviation 5.2) per interview. There were 167 different difficulties, which were classified into seven categories (introduction, initial contract, body of the interview, techniques and organization, interpersonal aspects, final contract and miscellaneous) and 20 subcategories. The 17 most frequently noted difficulties accounted for 40% of the total. CONCLUSIONS: The results constitute a useful starting point for developing a classification of residents' difficulties during clinical interviews. We believe that the list of difficulties is applicable to residents at all levels and in other specialties, especially in ambulatory settings. The list can be used to develop learning materials for supervisors and residents. PMID:1737313</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20849473','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20849473"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of a 'devil's staircase' in wave-particle interaction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Doveil, Fabrice; Macor, Alessandro; Elskens, Yves</p> <p>2006-09-15</p> <p>We report the experimental <span class="hlt">observation</span> of a 'devil's staircase' in a time-dependent system considered as a paradigm for the transition to large-scale chaos in the universality class of Hamiltonian systems. A test electron beam is used to <span class="hlt">observe</span> its non-self-consistent interaction with externally excited wave(s) in a traveling wave tube (TWT). A trochoidal energy analyzer records the beam energy distribution at the output of the interaction line. An arbitrary waveform generator is used to launch a prescribed spectrum of waves along the slow wave structure (a 4 m long helix) of the TWT. The resonant velocity domain associated to a single wave is <span class="hlt">observed</span>, as well as the transition to large-scale chaos when the resonant domains of two waves and their secondary resonances overlap. This transition exhibits a 'devil's staircase' behavior for increasing excitation amplitude, due to the nonlinear forcing by the second wave on the pendulum-like motion of a charged particle in one electrostatic wave.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22360715','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22360715"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of nanoparticle superlattice formation by using liquid cell transmission electron microscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Park, Jungwon; Zheng, Haimei; Lee, Won Chul; Geissler, Phillip L; Rabani, Eran; Alivisatos, A Paul</p> <p>2012-03-27</p> <p><span class="hlt">Direct</span> imaging of nanoparticle solutions by liquid phase transmission electron microscopy has enabled unique in situ studies of nanoparticle motion and growth. In the present work, we report on real-time formation of two-dimensional nanoparticle arrays in the very low diffusive limit, where nanoparticles are mainly driven by capillary forces and solvent fluctuations. We find that superlattice formation appears to be segregated into multiple regimes. Initially, the solvent front drags the nanoparticles, condensing them into an amorphous agglomerate. Subsequently, the nanoparticle crystallization into an array is driven by local fluctuations. Following the crystallization event, superlattice growth can also occur via the addition of individual nanoparticles drawn from outlying regions by different solvent fronts. The dragging mechanism is consistent with simulations based on a coarse-grained lattice gas model at the same limit. PMID:22360715</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20023162','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20023162"><span id="translatedtitle">High-temperature corrosion <span class="hlt">observed</span> in austenitic coils and tubes in a <span class="hlt">direct</span> reduction process</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Campillo, B.; Gonzalez, C.; Hernandez-Duque, G.; Juarez-Islas, J.A.</p> <p>2000-02-01</p> <p>The subject of this study is related to the performance of austenitic steel coils and tubes, in a range of temperatures between 425 and 870 C for the transport of reducing gas, in an installation involving the <span class="hlt">direct</span> reduction of iron-ore by reforming natural gas. Evidence is presented that metal dusting is not the only unique high-temperature corrosion mechanism that caused catastrophic failures of austenitic 304 (UNS S30400) coils and HK-40 (UNS J94204) tubes. Sensitization as well as stress corrosion cracking occurred in 304 stainless steel coils and metal dusting took place in HK-40 tubes, a high resistance alloy. The role of continuous injection of H{sub 2}S into the process is suggested to avoid the high resistance metal dusting corrosion mechanism found in this kind of installation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/0810.1899v1','EPRINT'); return false;" href="http://arxiv.org/pdf/0810.1899v1"><span id="translatedtitle">Paul trapping of radioactive 6He+ions and <span class="hlt">direct</span> <span class="hlt">observation</span> of their beta-decay</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>X. Flechard; E. Lienard; A. Mery; D. Rodriguez; G. Ban; D. Durand; F. Duval; M. Herbane; M. Labalme; F. Mauger; O. Naviliat-Cuncic; J. C. Thomas; Ph. Velten</p> <p>2008-10-10</p> <p>We demonstrate that abundant quantities of short-lived beta unstable ions can be trapped in a novel transparent Paul trap and that their decay products can <span class="hlt">directly</span> be detected in coincidence. Low energy 6He+ (807 ms half-life) ions were extracted from the SPIRAL source at GANIL, then decelerated, cooled and bunched by means of the buffer gas cooling technique. More than 10^8 ions have been stored over a measuring period of six days and about 10^5 decay coincidences between the beta particles and the 6Li^{++} recoiling ions have been recorded. The technique can be extended to other short-lived species, opening new possibilities for trap assisted decay experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930033738&hterms=Chlorine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DChlorine','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930033738&hterms=Chlorine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DChlorine"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of ClO from chlorine nitrate photolysis. [as mechanism of polar ozone depletion</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Minton, Timothy K.; Nelson, Christine M.; Moore, Teresa A.; Okumura, Mitchio</p> <p>1992-01-01</p> <p>Chlorine nitrate photolysis has been investigated with the use of a molecular beam technique. Excitation at both 248 and 193 nanometers led to photodissociation by two pathways, ClONO2 yields ClO + NO2 and ClONO2 yields Cl + NO3, with comparable yields. This experiment provides a <span class="hlt">direct</span> measurement of the ClO product channel and consequently raises the possibility of an analogous channel in ClO dimer photolysis. Photodissociation of the ClO dimer is a critical step in the catalytic cycle that is presumed to dominate polar stratospheric ozone destruction. A substantial yield of ClO would reduce the efficiency of this cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22261576','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22261576"><span id="translatedtitle"><span class="hlt">Direct</span> atomic-scale <span class="hlt">observation</span> of layer-by-layer oxide growth during magnesium oxidation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zheng, He; Wu, Shujing; Sheng, Huaping; Liu, Chun; Liu, Yu; Cao, Fan; Zhou, Zhichao; Zhao, Dongshan E-mail: dszhao@whu.edu.cn; Wang, Jianbo E-mail: dszhao@whu.edu.cn; Zhao, Xingzhong</p> <p>2014-04-07</p> <p>The atomic-scale oxide growth dynamics are <span class="hlt">directly</span> revealed by in situ high resolution transmission electron microscopy during the oxidation of Mg surface. The oxidation process is characterized by the layer-by-layer growth of magnesium oxide (MgO) nanocrystal via the adatom process. Consistently, the nucleated MgO crystals exhibit faceted surface morphology as enclosed by (200) lattice planes. It is believed that the relatively lower surface energies of (200) lattice planes should play important roles, governing the growth mechanism. These results facilitate the understanding of the nanoscale oxide growth mechanism that will have an important impact on the development of magnesium or magnesium alloys with improved resistance to oxidation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NatCo...4E2817C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NatCo...4E2817C"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the oxygenated species during oxygen reduction on a platinum fuel cell cathode</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Casalongue, Hernan Sanchez; Kaya, Sarp; Viswanathan, Venkatasubramanian; Miller, Daniel J.; Friebel, Daniel; Hansen, Heine A.; Nørskov, Jens K.; Nilsson, Anders; Ogasawara, Hirohito</p> <p>2013-12-01</p> <p>The performance of polymer electrolyte membrane fuel cells is limited by the reduction at the cathode of various oxygenated intermediates in the four-electron pathway of the oxygen reduction reaction. Here we use ambient pressure X-ray photoelectron spectroscopy, and <span class="hlt">directly</span> probe the correlation between the adsorbed species on the surface and the electrochemical potential. We demonstrate that, during the oxygen reduction reaction, hydroxyl intermediates on the cathode surface occur in several configurations with significantly different structures and reactivities. In particular, we find that near the open-circuit potential, non-hydrated hydroxyl is the dominant surface species. On the basis of density functional theory calculations, we show that the removal of hydration enhances the reactivity of oxygen species. Tuning the hydration of hydroxyl near the triple phase boundary will be crucial for designing more active fuel cell cathodes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1510.00036v2','EPRINT'); return false;" href="http://arxiv.org/pdf/1510.00036v2"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of Feshbach enhanced $\\it{s}$-wave scattering of fermions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Dina Genkina; Lauren M. Aycock; Benjamin K. Stuhl; Hsin-I Lu; Ross A. Williams; Ian B. Spielman</p> <p>2015-10-08</p> <p>We <span class="hlt">directly</span> measured the normalized $\\it{s}$-wave scattering cross-section of ultracold $^{40}\\rm{K}$ atoms across a magnetic-field Feshbach resonance by colliding pairs of degenerate Fermi gases (DFGs) and imaging the scattered atoms. We extracted the scattered fraction for a range of bias magnetic fields, and measured the resonance location to be $B_0 = 20.206(15)$ mT with width $\\Delta = 1.0(5)$ mT. To optimize the signal-to-noise ratio of atom number in scattering images, we developed techniques to interpret absorption images in a regime where recoil induced detuning corrections are significant. These imaging techniques are generally applicable to experiments with lighter alkalis that would benefit from maximizing signal-to-noise ratio on atom number counting at the expense of spatial imaging resolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1052159','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1052159"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of two-step crystallization in nanoparticle superlattice formation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Park, Jungwon; Zheng, Haimei; Lee, Won Chul; Geissler, Phillip L.; Rabani, Eran; Alivisatos, A. Paul</p> <p>2011-10-06</p> <p><span class="hlt">Direct</span> imaging of nanoparticle solutions by liquid phase transmission electron microscopy has enabled unique in-situ studies of nanoparticle motion and growth. In the present work, we report on real-time formation of two-dimensional nanoparticle arrays in the very low diffusive limit, where nanoparticles are mainly driven by capillary forces and solvent fluctuations. We find that superlattice formation appears to be segregated into multiple regimes. Initially, the solvent front drags the nanoparticles, condensing them into an amorphous agglomerate. Subsequently, the nanoparticle crystallization into an array is driven by local fluctuations. Following the crystallization event, superlattice growth can also occur via the addition of individual nanoparticles drawn from outlying regions by different solvent fronts. The dragging mechanism is consistent with simulations based on a coarse-grained lattice gas model at the same limit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26538051','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26538051"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Triplet-State Population Dynamics in the RNA Uracil Derivative 1-Cyclohexyluracil.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brister, Matthew M; Crespo-Hernández, Carlos E</p> <p>2015-11-01</p> <p>Investigation of the excited-state dynamics in nucleic acid monomers is an area of active research due to the crucial role these early events play in DNA and RNA photodamage. The dynamics and rate at which the triplet state is populated are key mechanistic pathways yet to be fully elucidated. <span class="hlt">Direct</span> spectroscopic evidence is presented in this contribution for intersystem crossing dynamics in a uracil derivative, 1-cyclohexyluracil. It is shown that intersystem crossing to the triplet manifold occurs in one picosecond or less in acetonitrile solution-at least an order of magnitude faster than previously estimated experimentally. Broadband transient absorption measurements also reveal the primary electronic relaxation pathways of the uracil chromophore, including the absorption spectra of the (1)??*, (1)n?*, and (3)??* states and the rates of vibrational cooling in the ground and (3)??* states. The experimental results are supported by density functional calculations. PMID:26538051</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/993850','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/993850"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Room-Temperature Polar Ordering in Colloidal GeTe Nanocrystals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Polking, Mark J.; Zheng, Haimei; Urban, Jeffrey J.; Milliron, Delia J.; Chan, Emory; Caldwell, Marissa A.; Raoux, Simone; Kisielowski, Christian F.; Ager III, Joel W.; Ramesh, Ramamoorthy; Alivisatos, A.P.</p> <p>2009-12-07</p> <p>Ferroelectrics and other materials that exhibit spontaneous polar ordering have demonstrated immense promise for applications ranging from non-volatile memories to microelectromechanical systems. However, experimental evidence of polar ordering and effective synthetic strategies for accessing these materials are lacking for low-dimensional nanomaterials. Here, we demonstrate the synthesis of size-controlled nanocrystals of the polar material germanium telluride (GeTe) using colloidal chemistry and provide the first <span class="hlt">direct</span> evidence of room-temperature polar ordering in nanocrystals less than 5 nm in size using aberration-corrected transmission electron microscopy. Synchrotron x-ray diffraction and Raman studies demonstrate a sizeable polar distortion and a reversible size-dependent polar phase transition in these nanocrystals. The stability of polar ordering in solution-processible nanomaterials suggests an economical avenue to Tbit/in2-density non-volatile memory devices and other applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AMTD....5.8131A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AMTD....5.8131A"><span id="translatedtitle"><span class="hlt">Direct</span>-sun total ozone data from a Bentham spectroradiometer: methodology and comparison with satellite <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Antón, M.; Román, R.; Valenzuela, A.; Olmo, F. J.; Alados-Arboledas, L.</p> <p>2012-11-01</p> <p>A methodology to obtain the total ozone column (TOC) from the <span class="hlt">direct</span>-solar spectral measurements of a Bentham spectroradiometer located at Granada (Spain) is presented in this paper. The method relies on the differential absorption technique using two pairs of <span class="hlt">direct</span> irradiance at adjacent wavelengths between 305 and 340 nm. The extraterrestrial constant was determined from the extrapolation to zero air mass of each wavelength pair (Langley plot method). We checked the strong influence of the cloud cover on the Bentham TOC measurements using simultaneous sky images taken with an All-sky camera. Thus, reliable TOC data are exclusively obtained during cloud-free conditions or partly cloudy conditions without the solar disk obstructed. In this work, the hourly TOC averages retrieved by the Bentham instrument with a~standard deviation smaller than 3% (~ 10 Dobson Unit) are selected as high-quality TOC data. The analysis of the diurnal TOC variations during cloud-free days showed a differential behavior between the morning and afternoon periods. Thus, while the mornings exhibit an almost stable pattern, the afternoons displays a monotonic TOC increase which could be related to photochemical processes in the lower troposphere associated with the formation of surface ozone. Finally, the Bentham TOC measurements were validated against the satellite data derived from three satellite instruments: OMI, GOME and SCIAMACHY. The mean absolute values of the relative differences between satellite and ground-based data were smaller than 3% which highlight the high reliability of the retrieval method proposed in this paper to derive TOC data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AMT.....6..637A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AMT.....6..637A"><span id="translatedtitle"><span class="hlt">Direct</span>-sun total ozone data from a spectroradiometer: methodology and comparison with satellite <span class="hlt">observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Antón, M.; Román, R.; Valenzuela, A.; Olmo, F. J.; Alados-Arboledas, L.</p> <p>2013-03-01</p> <p>A methodology to obtain the total ozone column (TOC) from the <span class="hlt">direct</span>-sun spectral measurements of a Bentham spectroradiometer located at Granada (Spain) is presented in this paper. The method relies on the differential absorption technique using two pairs of <span class="hlt">direct</span> irradiance at adjacent wavelengths between 305 and 340 nm. The extraterrestrial constant was determined from the extrapolation to zero air mass of each wavelength pair (Langley plot method). We checked the strong influence of the cloud cover on the Bentham TOC measurements using simultaneous sky images taken with an all-sky camera. Thus, reliable TOC data are exclusively obtained during cloud-free conditions or partly cloudy conditions without the solar disk obstructed. In this work, the hourly TOC averages retrieved by the Bentham instrument with a standard deviation smaller than 3% (~ 10 Dobson Unit) are selected as high-quality TOC data. The analysis of the diurnal TOC variations during cloud-free days in late spring and summer showed different TOC values between the morning and afternoon periods. Thus, while the mornings exhibit an almost stable pattern, the afternoons display a monotonic TOC increase which could be partially related to photochemical processes in the lower troposphere associated with the formation of surface ozone. Finally, the Bentham TOC measurements were compared against the satellite data derived from three satellite instruments: OMI, GOME and SCIAMACHY. The mean absolute values of the relative differences between satellite and ground-based data were smaller than 3%, highlighting the high reliability of the retrieval method proposed in this paper to derive TOC data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22365056','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22365056"><span id="translatedtitle"><span class="hlt">DIRECT</span> <span class="hlt">OBSERVATIONS</span> OF MAGNETIC FLUX ROPE FORMATION DURING A SOLAR CORONAL MASS EJECTION</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Song, H. Q.; Chen, Y.; Zhang, J.; Cheng, X.</p> <p>2014-09-10</p> <p>Coronal mass ejections (CMEs) are the most spectacular eruptive phenomena in the solar atmosphere. It is generally accepted that CMEs are the results of eruptions of magnetic flux ropes (MFRs). However, there is heated debate on whether MFRs exist prior to the eruptions or if they are formed during the eruptions. Several coronal signatures, e.g., filaments, coronal cavities, sigmoid structures, and hot channels (or hot blobs), are proposed as MFRs and <span class="hlt">observed</span> before the eruption, which support the pre-existing MFR scenario. There is almost no reported <span class="hlt">observation</span> of MFR formation during the eruption. In this Letter, we present an intriguing <span class="hlt">observation</span> of a solar eruptive event that occurred on 2013 November 21 with the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory, which shows the formation process of the MFR during the eruption in detail. The process began with the expansion of a low-lying coronal arcade, possibly caused by the flare magnetic reconnection underneath. The newly formed ascending loops from below further pushed the arcade upward, stretching the surrounding magnetic field. The arcade and stretched magnetic field lines then curved in just below the arcade vertex, forming an X-point. The field lines near the X-point continued to approach each other and a second magnetic reconnection was induced. It is this high-lying magnetic reconnection that led to the formation and eruption of a hot blob (?10 MK), presumably an MFR, producing a CME. We suggest that two spatially separated magnetic reconnections occurred in this event, which were responsible for producing the flare and the hot blob (CME)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015TDM.....2c4015S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015TDM.....2c4015S"><span id="translatedtitle">How to <span class="hlt">directly</span> <span class="hlt">observe</span> Landau levels in driven-dissipative strained honeycomb lattices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salerno, Grazia; Ozawa, Tomoki; Price, Hannah M.; Carusotto, Iacopo</p> <p>2015-09-01</p> <p>We study the driven-dissipative steady-state of a coherently driven Bose field in a honeycomb lattice geometry. In the presence of a suitable spatial modulation of the hopping amplitudes, a valley-dependent artificial magnetic field appears and the low-energy eigenmodes have the form of relativistic Landau levels. We show how the main properties of the Landau levels can be extracted by <span class="hlt">observing</span> the peaks in the absorption spectrum of the system and the corresponding spatial intensity distribution. Finally, quantitative predictions for realistic lattices based on photonic or microwave technologies are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhRvL.112w8301L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhRvL.112w8301L"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of the Coherent Nuclear Response after the Absorption of a Photon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liebel, M.; Schnedermann, C.; Bassolino, G.; Taylor, G.; Watts, A.; Kukura, P.</p> <p>2014-06-01</p> <p>How molecules convert light energy to perform a specific transformation is a fundamental question in photophysics. Ultrafast spectroscopy reveals the kinetics associated with electronic energy flow, but little is known about how absorbed photon energy drives nuclear motion. Here we used ultrabroadband transient absorption spectroscopy to monitor coherent vibrational energy flow after photoexcitation of the retinal chromophore. In the proton pump bacteriorhodopsin, we <span class="hlt">observed</span> coherent activation of hydrogen-out-of-plane wagging and backbone torsional modes that were replaced by unreactive coordinates in the solution environment, concomitant with a deactivation of the reactive relaxation pathway.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22510785','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22510785"><span id="translatedtitle">Singlet fission in rubrene single crystal: <span class="hlt">direct</span> <span class="hlt">observation</span> by femtosecond pump-probe spectroscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ma, Lin; Zhang, Keke; Kloc, Christian; Sun, Handong; Michel-Beyerle, Maria E; Gurzadyan, Gagik G</p> <p>2012-06-21</p> <p>The excited state dynamics of rubrene in solution and in the single crystal were studied by femtosecond pump-probe spectroscopy under various excitation conditions. Singlet fission was demonstrated to play a predominant role in the excited state relaxation of the rubrene crystal in contrast to rubrene in solution. Upon 500 nm excitation, triplet excitons form on the picosecond time scale via fission from the lowest excited singlet state. Upon 250 nm excitation, fission from upper excited singlet states is <span class="hlt">observed</span> within 200 fs. PMID:22510785</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990ApPhL..56.1597M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990ApPhL..56.1597M"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of ion transfer in contact charging between a metal and a polymer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mizes, H. A.; Conwell, E. M.; Salamida, D. P.</p> <p>1990-04-01</p> <p>Triboelectric charging between metals and insulators is usually thought to involve electron transfer. Doping some polymers with a small amount of salt can significantly change their charging properties, even reversing the sign to which they charge upon contact with a given metal. We show by means of secondary-ion mass spectrometry that ions of the salt are transferred across the interface in contacts between a doped polymer and a metal. Specifically, we <span class="hlt">observe</span> a transfer of bromine ions when polystyrene doped with a small amount of the salt cetylpyridinium bromide is contacted to an indium surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3020647','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3020647"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of stepped proteolipid ring rotation in E. coli FoF1-ATP synthase</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ishmukhametov, Robert; Hornung, Tassilo; Spetzler, David; Frasch, Wayne D</p> <p>2010-01-01</p> <p>Although single-molecule experiments have provided mechanistic insight for several molecular motors, these approaches have proved difficult for membrane bound molecular motors like the FoF1-ATP synthase, in which proton transport across a membrane is used to synthesize ATP. Resolution of smaller steps in Fo has been particularly hampered by signal-to-noise and time resolution. Here, we show the presence of a transient dwell between Fo subunits a and c by improving the time resolution to 10 ?s at unprecedented S/N, and by using Escherichia coli FoF1 embedded in lipid bilayer nanodiscs. The transient dwell interaction requires 163 ?s to form and 175 ?s to dissociate, is independent of proton transport residues aR210 and cD61, and behaves as a leash that <span class="hlt">allows</span> rotary motion of the c-ring to a limit of ?36° while engaged. This leash behaviour satisfies a requirement of a Brownian ratchet mechanism for the Fo motor where c-ring rotational diffusion is limited to 36°. PMID:21037553</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAP...118g5501B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAP...118g5501B"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of conductive filament formation in Alq3 based organic resistive memories</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Busby, Y.; Nau, S.; Sax, S.; List-Kratochvil, E. J. W.; Novak, J.; Banerjee, R.; Schreiber, F.; Pireaux, J.-J.</p> <p>2015-08-01</p> <p>This work explores resistive switching mechanisms in non-volatile organic memory devices based on tris(8-hydroxyquinolie)aluminum (Alq3). Advanced characterization tools are applied to investigate metal diffusion in ITO/Alq3/Ag memory device stacks leading to conductive filament formation. The morphology of Alq3/Ag layers as a function of the metal evaporation conditions is studied by X-ray reflectivity, while depth profile analysis with X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry is applied to characterize operational memory elements displaying reliable bistable current-voltage characteristics. 3D images of the distribution of silver inside the organic layer clearly point towards the existence of conductive filaments and <span class="hlt">allow</span> for the identification of the initial filament formation and inactivation mechanisms during switching of the device. Initial filament formation is suggested to be driven by field assisted diffusion of silver from abundant structures formed during the top electrode evaporation, whereas thermochemical effects lead to local filament inactivation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AIPC.1027.1156C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AIPC.1027.1156C"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Phase Transition Dynamics in Suspensions of Soft Colloidal Hydrogel Particles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cho, Jae Kyu; Meng, Zhiyong; Lyon, L. Andrew; Breedveld, Victor</p> <p>2008-07-01</p> <p>Due to the tunability of their softness and volume as a function of temperature, poly(N-isopropylacrylamide) (pNIPAm) hydrogel particles have emerged as a model system for soft colloidal spheres. By introducing AAc as comonomer, one can also tune the particle volume via pH. We report on the phase behavior of these stimuli-responsive colloids as measured with a microdialysis cell. This device, which integrates microfluidics with Particle Tracking Video-microscopy <span class="hlt">allows</span> for simple and quick investigation of the phase behavior of suspensions the soft colloidal hydrogel as a function of pH as well as its packing density. In particular, we demonstrate the existence of an unusually broad liquid/crystal coexistence region as a function of effective particle volume fraction. Additionally, we reveal that nonequilibrium jammed states can be created in the coexistence region upon sudden large changes of pH. The phase diagram is indicative of complex interparticle interactions with weakly attractive components.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..SHK.E4004K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..SHK.E4004K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of an abrupt insulator-to-metal transition in dense liquid deuterium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knudson, Marcus; Desjarlais, Michael; Becker, Andeas; Lemke, Raymond; Cochrane, Kyle; Savage, Mark; Bliss, David; Mattsson, Thomas; Redmer, Ronald</p> <p>2015-06-01</p> <p>Recently a so-called shock-ramp platform has been developed on the Sandia Z Accelerator to access off-Hugoniot states in liquids. The accelerator delivers a two-step current pulse; the first accelerates the electrode to a reasonably constant velocity, which upon impact with the sample cell creates a well-defined shock, the subsequent current rise produces ramp compression from the initially shocked state. This technique generates relatively cool (~1-2 kK), high pressure (>300 GPa), high compression (~10-15 fold compression) states, <span class="hlt">allowing</span> experimental access to the region of phase space where hydrogen is predicted to undergo a first-order phase transition from an insulating molecular-like liquid to a conducting atomic-like liquid. In this talk we will discuss the experimental platform, survey the various theoretical predictions for the liquid-liquid, insulator-to-metal transition in hydrogen, and present the results of experiments that clearly show an abrupt transition to a metallic state. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26480438','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26480438"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of optical near field in nanophotonics devices at the nanoscale using Scanning Thermal Microscopy.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Grajower, Meir; Desiatov, Boris; Goykhman, Ilya; Stern, Liron; Mazurski, Noa; Levy, Uriel</p> <p>2015-10-19</p> <p>In recent years, following the miniaturization and integration of passive and active nanophotonic devices, thermal characterization of such devices at the nanoscale is becoming a task of crucial importance. The Scanning Thermal Microscopy (SThM) is a natural candidate for performing this task. However, it turns out that the SThM capability to precisely map the temperature of a photonic sample in the presence of light interacting with the sample is limited. This is because of the significant absorption of light by the SThM probe. As a result, the temperature of the SThM probe increases and a significant electrical signal which is <span class="hlt">directly</span> proportional to the light intensity is obtained. As such, instead of measuring the temperature of the sample, one may <span class="hlt">directly</span> measure the light intensity profile. While this is certainly a limitation in the context of thermal characterization of nanophotonic devices, this very property provides a new opportunity for optical near field characterization. In this paper we demonstrate numerically and experimentally the optical near field measurements of nanophotonic devices using a SThM probe. The system is characterized using several sets of samples with different properties and various wavelengths of operation. Our measurements indicate that the light absorption by the probe can be even larger than the light induced heat generation in the sample. The frequency response of the SThM system is characterized and the 3 dB frequency response was found to be ~1.5 kHz. The simplicity of the SThM system which eliminates the need for complex optical measurement setups together with its broadband wavelength of operation makes this approach an attractive alternative to the more conventional aperture and apertureless NSOM approaches. Finally, referring to its original role in characterizing thermal effects at the nanoscale, we propose an approach for characterizing the temperature profile of nanophotonic devices which are heated by light absorption within the device. This is achieved by spatially separating between the optical near field distribution and the SThM probe, taking advantage of the broader temperature profile as compared to the more localized light profile. PMID:26480438</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2682692','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2682692"><span id="translatedtitle">Epidemiologic Studies of Cancer in Agricultural Populations: <span class="hlt">Observations</span> and Future <span class="hlt">Directions</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Blair, Aaron; Freeman, Laura Beane</p> <p>2009-01-01</p> <p>This paper reviews epidemiologic studies of cancer among agricultural populations to identify possible associations and to provide a focus for future investigations. Meta-analyses of mortality surveys of farmers find excesses of several cancers, including connective tissue, non-Hodgkin lymphoma, Hodgkin disease, and multiple myeloma and cancers of the skin, stomach and brain and deficits for total mortality, heart disease, total cancer, and cancers of the esophagus, colon, lung and bladder. Meta-analyses of studies of individual cancers also support these findings indicating a need to identify exposures and lifestyle factors that might account for this mortality pattern. Although cancer studies of other occupations that might have pesticide exposures in common with farmers show some similarities with <span class="hlt">observations</span> among farmers, the overall patterns are quite different. This suggests that pesticides are not likely to fully explain the cancer and other disease patterns <span class="hlt">observed</span> among farmers. Because exposures vary by type of farm operation, exposures for individual farmers can differ considerably. Studies in the future need to focus on the full range of exposures to fully understand the cancer pattern in farmers. PMID:19437268</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999AAS...195.0504K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999AAS...195.0504K"><span id="translatedtitle"><span class="hlt">Observations</span> of an Unusual Extended Nonthermal Radio Source in the <span class="hlt">Direction</span> of the Galactic Center</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kazi, T.; LaRosa, T. N.; Kassim, N.; Lazio, T. J. W.; Lang, C. C.; Anantharamaiah, K.</p> <p>1999-12-01</p> <p>We present 20 and 90 cm VLA <span class="hlt">observations</span> of an unusual extended nonthermal radio source near the galactic center, G359.87+0.44. This source was recently discovered on a wide-field VLA B-C-D 90 cm image of the galactic center (LaRosa et al 2000). It is located approximately 0.5\\arcdeg\\ northwest of Sgr A. Although the source morphology is somewhat different at 90 and 20 cm, the strongest emission comes from a linear structure with a length of 7\\arcmin similar to the nonthermal filaments also found in the GC region. However, the 20/90 cm spectral index (the spectral index ? of a source to be S ? ? , where S is its flux density and ? is its frequency) along the length of this source decreases uniformly from -0.6 to -1.4, in constrast to the constant (as a function of position) spectral indices exhibited by the nonthermal filaments. We present several alternative interpretations and plans for future <span class="hlt">observations</span>. Basic research in radio astronomy at the NRL is supported by the Office of Naval Research. TNL acknowledges a NAVY-ASEE summer faculty fellowship at the NRL.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..MARD29010K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..MARD29010K"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of asymmetric band structure of bilayer graphene through quantum capacitance measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanayama, Kaoru; Nagashio, Kosuke; Nishimura, Tomonori; Toriumi, Akira</p> <p>2014-03-01</p> <p>Although upper conduction and valence sub-bands in bilayer graphene are known to be asymmetric, a detailed analysis based on the electrical measurements is very limited due to the infirm quality of gate insulator. In this study, the electrical quality of the top-gate Y2O3 insulator is drastically improved by the high-pressure O2 post-deposition annealing at 100 atm and the carrier density of ~8*1013 cm-2 is achieved. In quantum capacitance measurements, the drastic increase of the density of states is <span class="hlt">observed</span> in addition to the van Hove singularity, suggesting that the Fermi energy reaches upper sub-band. At the same carrier density, the sudden reduction of the conductivity is <span class="hlt">observed</span>, indicating that the inter-band scattering occurs. The estimated carrier density required to fill the upper sub-bands is different between electron and hole sides, i.e., asymmetric band structure between upper conduction and valence bands is revealed by the electrical measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23442920','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23442920"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of protein unfolded state compaction in the presence of macromolecular crowding.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mikaelsson, Therese; Adén, Jörgen; Johansson, Lennart B-Å; Wittung-Stafshede, Pernilla</p> <p>2013-02-01</p> <p>Proteins fold and function in cellular environments that are crowded with other macromolecules. As a consequence of excluded volume effects, compact folded states of proteins should be indirectly stabilized due to destabilization of extended unfolded conformations. Here, we assess the role of excluded volume in terms of protein stability, structural dimensions and folding dynamics using a sugar-based crowding agent, dextran 20, and the small ribosomal protein S16 as a model system. To specifically address dimensions, we labeled the protein with BODIPY at two positions and measured Trp-BODIPY distances under different conditions. As expected, we found that dextran 20 (200 mg/ml) stabilized the variants against urea-induced unfolding. At conditions where the protein is unfolded, Förster resonance energy transfer measurements reveal that in the presence of dextran, the unfolded ensemble is more compact and there is residual structure left as probed by far-ultraviolet circular dichroism. In the presence of a crowding agent, folding rates are faster in the two-state regime, and at low denaturant concentrations, a kinetic intermediate is favored. Our study provides <span class="hlt">direct</span> evidence for protein unfolded-state compaction in the presence of macromolecular crowding along with its energetic and kinetic consequences. PMID:23442920</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JSSCh.186..116S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JSSCh.186..116S"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of grafting interlayer phosphate in Mg/Al layered double hydroxides</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shimamura, Akihiro; Kanezaki, Eiji; Jones, Mark I.; Metson, James B.</p> <p>2012-02-01</p> <p>The grafting of interlayer phosphate in synthetic Mg/Al layered double hydroxides with interlayer hydrogen phosphate (LDH-HPO4) has been studied by XRD, TG/DTA, FT-IR, XPS and XANES. The basal spacing of crystalline LDH-HPO4 decreases in two stages with increasing temperature, from 1.06 nm to 0.82 nm at 333 K in the first transition, and to 0.722 nm at 453 K in the second. The first stage occurs due to the loss of interlayer water and rearrangement of the interlayer HPO42-. In the second transition, the interlayer phosphate is grafted to the layer by the formation of <span class="hlt">direct</span> bonding to metal cations in the layer, accompanied by a change in polytype of the crystalline structure. The grafted phosphate becomes immobilized and cannot be removed by anion-exchange with 1-octanesulfonate. The LDH is amorphous at 743 K but decomposes to Mg3(PO4)2, AlPO4, MgO and MgAl2O4 after heated to 1273 K.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22102260','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22102260"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of enhanced emission sites in nitrogen implanted hybrid structured ultrananocrystalline diamond films</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Panda, Kalpataru; Sundaravel, B.; Panigrahi, B. K.; Chen, Huang-Chin; Lin, I.-Nan</p> <p>2013-02-07</p> <p>A hybrid-structured ultrananocrystalline diamond (h-UNCD) film, synthesized on Si-substrates by a two-step microwave plasma enhanced chemical vapour deposition (MPECVD) process, contains duplex structure with large diamond aggregates evenly dispersed in a matrix of ultra-small grains ({approx}5 nm). The two-step plasma synthesized h-UNCD films exhibit superior electron field emission (EFE) properties than the one-step MPECVD deposited UNCD films. Nitrogen-ion implantation/post-annealing processes further improve the EFE properties of these films. Current imaging tunnelling spectroscopy in scanning tunnelling spectroscopy mode <span class="hlt">directly</span> shows increased density of emission sites in N implanted/post-annealed h-UNCD films than as-prepared one. X-ray photoelectron spectroscopy measurements show increased sp{sup 2} phase content and C-N bonding fraction in N ion implanted/post-annealed films. Transmission electron microscopic analysis reveals that the N implantation/post-annealing processes induce the formation of defects in the diamond grains, which decreases the band gap and increases the density of states within the band gap of diamond. Moreover, the formation of nanographitic phase surrounding the small diamond grains enhanced the conductivity at the diamond grain boundaries. Both of the phenomena enhance the EFE properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JCAP...12..015B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JCAP...12..015B"><span id="translatedtitle">What is the probability that <span class="hlt">direct</span> detection experiments have <span class="hlt">observed</span> dark matter?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bozorgnia, Nassim; Schwetz, Thomas</p> <p>2014-12-01</p> <p>In Dark Matter <span class="hlt">direct</span> detection we are facing the situation of some experiments reporting positive signals which are in conflict with limits from other experiments. Such conclusions are subject to large uncertainties introduced by the poorly known local Dark Matter distribution. We present a method to calculate an upper bound on the joint probability of obtaining the outcome of two potentially conflicting experiments under the assumption that the Dark Matter hypothesis is correct, but completely independent of assumptions about the Dark Matter distribution. In this way we can quantify the compatibility of two experiments in an astrophysics independent way. We illustrate our method by testing the compatibility of the hints reported by DAMA and CDMS-Si with the limits from the LUX and SuperCDMS experiments. The method does not require Monte Carlo simulations but is mostly based on using Poisson statistics. In order to deal with signals of few events we introduce the so-called ``signal length'' to take into account energy information. The signal length method provides a simple way to calculate the probability to obtain a given experimental outcome under a specified Dark Matter and background hypothesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCo...6E8691S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCo...6E8691S"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of many-body charge density oscillations in a two-dimensional electron gas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sessi, Paolo; Silkin, Vyacheslav M.; Nechaev, Ilya A.; Bathon, Thomas; El-Kareh, Lydia; Chulkov, Evgueni V.; Echenique, Pedro M.; Bode, Matthias</p> <p>2015-10-01</p> <p>Quantum interference is a striking manifestation of one of the basic concepts of quantum mechanics: the particle-wave duality. A spectacular visualization of this effect is the standing wave pattern produced by elastic scattering of surface electrons around defects, which corresponds to a modulation of the electronic local density of states and can be imaged using a scanning tunnelling microscope. To date, quantum-interference measurements were mainly interpreted in terms of interfering electrons or holes of the underlying band-structure description. Here, by imaging energy-dependent standing-wave patterns at noble metal surfaces, we reveal, in addition to the conventional surface-state band, the existence of an `anomalous' energy band with a well-defined dispersion. Its origin is explained by the presence of a satellite in the structure of the many-body spectral function, which is related to the acoustic surface plasmon. Visualizing the corresponding charge oscillations provides thus <span class="hlt">direct</span> access to many-body interactions at the atomic scale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26498368','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26498368"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of many-body charge density oscillations in a two-dimensional electron gas.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sessi, Paolo; Silkin, Vyacheslav M; Nechaev, Ilya A; Bathon, Thomas; El-Kareh, Lydia; Chulkov, Evgueni V; Echenique, Pedro M; Bode, Matthias</p> <p>2015-01-01</p> <p>Quantum interference is a striking manifestation of one of the basic concepts of quantum mechanics: the particle-wave duality. A spectacular visualization of this effect is the standing wave pattern produced by elastic scattering of surface electrons around defects, which corresponds to a modulation of the electronic local density of states and can be imaged using a scanning tunnelling microscope. To date, quantum-interference measurements were mainly interpreted in terms of interfering electrons or holes of the underlying band-structure description. Here, by imaging energy-dependent standing-wave patterns at noble metal surfaces, we reveal, in addition to the conventional surface-state band, the existence of an 'anomalous' energy band with a well-defined dispersion. Its origin is explained by the presence of a satellite in the structure of the many-body spectral function, which is related to the acoustic surface plasmon. Visualizing the corresponding charge oscillations provides thus <span class="hlt">direct</span> access to many-body interactions at the atomic scale. PMID:26498368</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10115003','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10115003"><span id="translatedtitle">The <span class="hlt">direct</span> <span class="hlt">observation</span> of alkali vapor species in biomass combustion and gasification</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>French, R.J.; Dayton, D.C.; Milne, T.A.</p> <p>1994-01-01</p> <p>This report summarizes new data from screening various feedstocks for alkali vapor release under combustion conditions. The successful development of a laboratory flow reactor and molecular beam, mass spectrometer interface is detailed. Its application to several herbaceous and woody feedstocks, as well as a fast-pyrolysis oil, under 800 and 1,100{degrees}C batch combustion, is documented. Chlorine seems to play a large role in the facile mobilization of potassium. Included in the report is a discussion of relevant literature on the alkali problem in combustors and turbines. Highlighted are the phenomena identified in studies on coal and methods that have been applied to alkali speciation. The nature of binding of alkali in coal versus biomass is discussed, together with the implications for the ease of release. Herbaceous species and many agricultural residues appear to pose significant problems in release of alkali species to the vapor at typical combustor temperatures. These problems could be especially acute in <span class="hlt">direct</span> combustion fired turbines, but may be ameliorated in integrated gasification combined cycles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22382089','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22382089"><span id="translatedtitle">What is the probability that <span class="hlt">direct</span> detection experiments have <span class="hlt">observed</span> dark matter?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bozorgnia, Nassim; Schwetz, Thomas E-mail: schwetz@fysik.su.se</p> <p>2014-12-01</p> <p>In Dark Matter <span class="hlt">direct</span> detection we are facing the situation of some experiments reporting positive signals which are in conflict with limits from other experiments. Such conclusions are subject to large uncertainties introduced by the poorly known local Dark Matter distribution. We present a method to calculate an upper bound on the joint probability of obtaining the outcome of two potentially conflicting experiments under the assumption that the Dark Matter hypothesis is correct, but completely independent of assumptions about the Dark Matter distribution. In this way we can quantify the compatibility of two experiments in an astrophysics independent way. We illustrate our method by testing the compatibility of the hints reported by DAMA and CDMS-Si with the limits from the LUX and SuperCDMS experiments. The method does not require Monte Carlo simulations but is mostly based on using Poisson statistics. In order to deal with signals of few events we introduce the so-called ''signal length'' to take into account energy information. The signal length method provides a simple way to calculate the probability to obtain a given experimental outcome under a specified Dark Matter and background hypothesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1410.6160v2','EPRINT'); return false;" href="http://arxiv.org/pdf/1410.6160v2"><span id="translatedtitle">What is the probability that <span class="hlt">direct</span> detection experiments have <span class="hlt">observed</span> Dark Matter?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Nassim Bozorgnia; Thomas Schwetz</p> <p>2014-11-17</p> <p>In Dark Matter <span class="hlt">direct</span> detection we are facing the situation of some experiments reporting positive signals which are in conflict with limits from other experiments. Such conclusions are subject to large uncertainties introduced by the poorly known local Dark Matter distribution. We present a method to calculate an upper bound on the joint probability of obtaining the outcome of two potentially conflicting experiments under the assumption that the Dark Matter hypothesis is correct, but completely independent of assumptions about the Dark Matter distribution. In this way we can quantify the compatibility of two experiments in an astrophysics independent way. We illustrate our method by testing the compatibility of the hints reported by DAMA and CDMS-Si with the limits from the LUX and SuperCDMS experiments. The method does not require Monte Carlo simulations but is mostly based on using Poisson statistics. In order to deal with signals of few events we introduce the so-called "signal length" to take into account energy information. The signal length method provides a simple way to calculate the probability to obtain a given experimental outcome under a specified Dark Matter and background hypothesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22218216','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22218216"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of interface and nanoscale compositional modulation in ternary III-As heterostructure nanowires</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Venkatesan, Sriram; Scheu, Christina; Madsen, Morten H.; Krogstrup, Peter; Johnson, Erik; Schmid, Herbert</p> <p>2013-08-05</p> <p>Straight, axial InAs nanowire with multiple segments of Ga{sub x}In{sub 1?x}As was grown. High resolution X-ray energy-dispersive spectroscopy (EDS) mapping reveals the distribution of group III atoms at the axial interfaces and at the sidewalls. Significant Ga enrichment, accompanied by a structural change is <span class="hlt">observed</span> at the Ga{sub x}In{sub 1?x}As/InAs interfaces and a higher Ga concentration for the early grown Ga{sub x}In{sub 1?x}As segments. The elemental map and EDS line profile infer Ga enrichment at the facet junctions between the sidewalls. The relative chemical potentials of ternary alloys and the thermodynamic driving force for liquid to solid transition explains the growth mechanisms behind the enrichment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4495604','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4495604"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of catalytic oxidation of particulate matter using in situ TEM</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kamatani, Kohei; Higuchi, Kimitaka; Yamamoto, Yuta; Arai, Shigeo; Tanaka, Nobuo; Ogura, Masaru</p> <p>2015-01-01</p> <p>The ability to <span class="hlt">observe</span> chemical reactions at the molecular level convincingly demonstrates the physical and chemical phenomena occurring throughout a reaction mechanism. Videos obtained through in situ transmission electron microscopy (TEM) revealed the oxidation of catalytic soot under practical reaction conditions. Carbon oxidation reactions using Ag/SiO2 or Cs2CO3/nepheline catalysts were performed at 330?°C under an O2 flow of 0.5?Pa in the TEM measurement chamber. Ag/SiO2 catalyzed the reaction at the interface of the mobile Ag species and carbon, while the Cs species was fixed on the nepheline surface during the reaction. In the latter case, carbon particles moved, remained attached to the Cs2CO3/nepheline surface, and were consumed at the interface by the oxidation reaction. Using this technique, we were able to visualize such mobile and immobile catalysis according to different mechanisms. PMID:26154580</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17769756','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17769756"><span id="translatedtitle">Laser beam <span class="hlt">directed</span> at the lunar retro-reflector array: <span class="hlt">observations</span> of the first returns.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Faller, J; Winer, I; Carrion, W; Johnson, T S; Spadin, P; Robinson, L; Wampler, E J; Wieber, D</p> <p>1969-10-01</p> <p>On 1 August between 10:15 and 12:50 Universal Time, with the Lick Observatory 120-inch (304-cm) telescope and a laser operating at 6943 angstroms, return signals from an optical retro-reflector array placed on the moon by the Apollo 11 astronauts were successfully detected. After the return signal was first detected it continued to appear with the expected time delay for the remainder of the night. The <span class="hlt">observed</span> range is in excellent agreement with the predicted ephemeris. Transmitting between 7 and 8 joules per pulse, we found that each return signal averaged more than one photoelectron. This is in good agreement with calculations of the expected signal strength. PMID:17769756</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4633643','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4633643"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> and temperature control of the surface Dirac gap in a topological crystalline insulator</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wojek, B. M.; Berntsen, M. H.; Jonsson, V.; Szczerbakow, A.; Dziawa, P.; Kowalski, B. J.; Story, T.; Tjernberg, O.</p> <p>2015-01-01</p> <p>Since the advent of topological insulators hosting Dirac surface states, efforts have been made to gap these states in a controllable way. A new route to accomplish this was opened up by the discovery of topological crystalline insulators where the topological states are protected by crystal symmetries and thus prone to gap formation by structural changes of the lattice. Here we show a temperature-driven gap opening in Dirac surface states within the topological crystalline insulator phase in (Pb,Sn)Se. By using angle-resolved photoelectron spectroscopy, the gap formation and mass acquisition is studied as a function of composition and temperature. The resulting <span class="hlt">observations</span> lead to the addition of a temperature- and composition-dependent boundary between massless and massive Dirac states in the topological phase diagram for (Pb,Sn)Se (001). Overall, our results experimentally establish the possibility to tune between massless and massive topological states on the surface of a topological system. PMID:26458506</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26561978','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26561978"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Confinement-Induced Charge Inversion at a Metal Surface.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tivony, Ran; Yaakov, Dan Ben; Silbert, Gilad; Klein, Jacob</p> <p>2015-12-01</p> <p>Surface interactions across water are central to areas from nanomedicine to colloidal stability. They are predominantly a combination of attractive but short-ranged dispersive (van der Waals) forces, and long-ranged electrostatic forces between the charged surfaces. Here we show, using a surface force balance, that electrostatic forces between two surfaces across water, one at constant charge while the other (a molecularly smooth metal surface) is at constant potential of the same sign, may revert smoothly from repulsion to attraction on progressive confinement of the aqueous intersurface gap. This remarkable effect, long predicted theoretically in the classic Gouy-Chapman (Poisson-Boltzmann) model but never previously experimentally <span class="hlt">observed</span>, unambiguously demonstrates surface charge reversal at the metal-water surface. This experimental confirmation emphasizes the implications for interactions of dielectrics with metal surfaces in aqueous media. PMID:26561978</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22415179','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22415179"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of electron emission and recombination processes by time domain measurements of charge pumping current</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hori, Masahiro Watanabe, Tokinobu; Ono, Yukinori; Tsuchiya, Toshiaki</p> <p>2015-01-26</p> <p>To analyze the charge pumping (CP) sequence in detail, the source/drain electron current and the substrate hole current under the CP mode of transistors are simultaneously monitored in the time domain. Peaks are <span class="hlt">observed</span> in both the electron and hole currents, which are, respectively, attributed to the electron emission from the interface defects and to the recombination with holes. The peak caused by the electron emission is found to consist of two components, strongly suggesting that the present time-domain measurement can enable us to resolve different kinds of interface defects. Investigating the correlation between the number of emitted and recombined electrons reveals that only one of the two components contributes to the CP current for the gate-pulse fall time from 6.25?×?10{sup ?4} to 1.25?×?10{sup ?2} s.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26359336','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26359336"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of ultrafast collective motions in CO myoglobin upon ligand dissociation.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Barends, Thomas R M; Foucar, Lutz; Ardevol, Albert; Nass, Karol; Aquila, Andrew; Botha, Sabine; Doak, R Bruce; Falahati, Konstantin; Hartmann, Elisabeth; Hilpert, Mario; Heinz, Marcel; Hoffmann, Matthias C; Köfinger, Jürgen; Koglin, Jason E; Kovacsova, Gabriela; Liang, Mengning; Milathianaki, Despina; Lemke, Henrik T; Reinstein, Jochen; Roome, Christopher M; Shoeman, Robert L; Williams, Garth J; Burghardt, Irene; Hummer, Gerhard; Boutet, Sébastien; Schlichting, Ilme</p> <p>2015-10-23</p> <p>The hemoprotein myoglobin is a model system for the study of protein dynamics. We used time-resolved serial femtosecond crystallography at an x-ray free-electron laser to resolve the ultrafast structural changes in the carbonmonoxy myoglobin complex upon photolysis of the Fe-CO bond. Structural changes appear throughout the protein within 500 femtoseconds, with the C, F, and H helices moving away from the heme cofactor and the E and A helices moving toward it. These collective movements are predicted by hybrid quantum mechanics/molecular mechanics simulations. Together with the <span class="hlt">observed</span> oscillations of residues contacting the heme, our calculations support the prediction that an immediate collective response of the protein occurs upon ligand dissociation, as a result of heme vibrational modes coupling to global modes of the protein. PMID:26359336</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/astro-ph/0604145v1','EPRINT'); return false;" href="http://arxiv.org/pdf/astro-ph/0604145v1"><span id="translatedtitle">Amplified Doppler shift <span class="hlt">observed</span> in diffraction images as function of the COBE "ether drift" <span class="hlt">direction</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>C. E. Navia; C. R. A. Augusto</p> <p>2006-04-06</p> <p>We report results on an ``one-way light path'' laser diffraction experiment as a function of the laser beam alignment relative to the Earth's velocity vector obtained by COBE measurements of the Doppler shift in the cosmic microwave background radiation (CMBR). An amplified Doppler shift is <span class="hlt">observed</span> in the diffraction images, and the effect is compatible with a ``dipole'' speed of light anisotropy due to Earth's motion relative to the ``CMBR rest frame'', with an amplitude of $\\delta c/\\bar{c}=0.00123$. This amplitude coincides with the value of the dipole temperature anisotropy $\\delta T/\\bar{T}=0.00123$ of the CMBR obtained by COBE. Our results point out that it is not possible to neglect the preferred frame imposed by the cosmology and they are well described by the Ether Gauge Theory (an extension of the Lorentz's ether theory) and it satisfies the cosmological time boundary condition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4639892','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4639892"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of ultrafast coherent exciton dynamics in helical ?-stacks of self-assembled perylene bisimides</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Sung, Jooyoung; Kim, Pyosang; Fimmel, Benjamin; Würthner, Frank; Kim, Dongho</p> <p>2015-01-01</p> <p>Ever since the discovery of dye self-assemblies in nature, there have been tremendous efforts to exploit biomimetic supramolecular assemblies for tailored artificial photon processing materials. This feature necessarily has resulted in an increasing demand for understanding exciton dynamics in the dye self-assemblies. In a sharp contrast with J-type aggregates, however, the detailed <span class="hlt">observation</span> of exciton dynamics in H-type aggregates has remained challenging. In this study, as we succeed in measuring transient fluorescence from Frenkel state of ?-stacked perylene tetracarboxylic acid bisimide dimer and oligomer aggregates, we present an experimental demonstration on Frenkel exciton dynamics of archetypal columnar ?–? stacks of dyes. The analysis of the vibronic peak ratio of the transient fluorescence spectra reveals that unlike the simple ?-stacked dimer, the photoexcitation energy in the columnar ?-stacked oligomer aggregates is initially delocalized over at least three molecular units and moves coherently along the chain in tens of femtoseconds, preceding excimer formation process. PMID:26492820</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvE..92c2202P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvE..92c2202P"><span id="translatedtitle">S -shaped flow curves of shear thickening suspensions: <span class="hlt">Direct</span> <span class="hlt">observation</span> of frictional rheology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pan, Zhongcheng; de Cagny, Henri; Weber, Bart; Bonn, Daniel</p> <p>2015-09-01</p> <p>We study the rheological behavior of concentrated granular suspensions of simple spherical particles. Under controlled stress, the system exhibits an S -shaped flow curve (stress vs shear rate) with a negative slope in between the low-viscosity Newtonian regime and the shear thickened regime. Under controlled shear rate, a discontinuous transition between the two states is <span class="hlt">observed</span>. Stress visualization experiments with a fluorescent probe suggest that friction is at the origin of shear thickening. Stress visualization shows that the stress in the system remains homogeneous (no shear banding) if a stress is imposed that is intermediate between the high- and low-stress branches. The S -shaped shear thickening is then due to the discontinuous formation of a frictional force network between particles upon increasing the stress.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCo...6E8463W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCo...6E8463W"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> and temperature control of the surface Dirac gap in a topological crystalline insulator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wojek, B. M.; Berntsen, M. H.; Jonsson, V.; Szczerbakow, A.; Dziawa, P.; Kowalski, B. J.; Story, T.; Tjernberg, O.</p> <p>2015-10-01</p> <p>Since the advent of topological insulators hosting Dirac surface states, efforts have been made to gap these states in a controllable way. A new route to accomplish this was opened up by the discovery of topological crystalline insulators where the topological states are protected by crystal symmetries and thus prone to gap formation by structural changes of the lattice. Here we show a temperature-driven gap opening in Dirac surface states within the topological crystalline insulator phase in (Pb,Sn)Se. By using angle-resolved photoelectron spectroscopy, the gap formation and mass acquisition is studied as a function of composition and temperature. The resulting <span class="hlt">observations</span> lead to the addition of a temperature- and composition-dependent boundary between massless and massive Dirac states in the topological phase diagram for (Pb,Sn)Se (001). Overall, our results experimentally establish the possibility to tune between massless and massive topological states on the surface of a topological system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22039299','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22039299"><span id="translatedtitle">EXTREME-ULTRAVIOLET SPECTROSCOPIC <span class="hlt">OBSERVATION</span> OF <span class="hlt">DIRECT</span> CORONAL HEATING DURING A C-CLASS SOLAR FLARE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Brosius, Jeffrey W.</p> <p>2012-07-20</p> <p>With the Coronal Diagnostic Spectrometer operating in rapid cadence (9.8 s) stare mode during a C6.6 flare on the solar disk, we <span class="hlt">observed</span> a sudden brightening of Fe XIX line emission (formed at temperature T Almost-Equal-To 8 MK) above the pre-flare noise without a corresponding brightening of emission from ions formed at lower temperatures, including He I (0.01 MK), O V (0.25 MK), and Si XII (2 MK). The sudden brightening persisted as a plateau of Fe XIX intensity that endured more than 11 minutes. The Fe XIX emission at the rise and during the life of the plateau showed no evidence of significant bulk velocity flows, and hence cannot be attributed to chromospheric evaporation. However, the line width showed a significant broadening at the rise of the plateau, corresponding to nonthermal velocities of at least 89 km s{sup -1} due to reconnection outflows or turbulence. During the plateau He I, O V, and Si XII brightened at successively later times starting about 3.5 minutes after Fe XIX, which suggests that these brightenings were produced by thermal conduction from the plasma that produced the Fe XIX line emission; however, we cannot rule out the possibility that they were produced by a weak beam of nonthermal particles. We interpret an <span class="hlt">observed</span> shortening of the O V wavelength for about 1.5 minutes toward the middle of the plateau to indicate new upward motions driven by the flare, as occurs during gentle chromospheric evaporation; relative to a quiescent interval shortly before the flare, the O V upward velocity was around -10 km s{sup -1}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23088251','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23088251"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of giant Pickering emulsion and colloidosome droplet interaction and stability.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thompson, Kate L; Giakoumatos, Emma C; Ata, Seher; Webber, Grant B; Armes, Steven P; Wanless, Erica J</p> <p>2012-12-01</p> <p>The interactions of two 2-mm pendant oil droplets grown in the presence of an aqueous solution of poly(glycerol monomethacrylate)-stabilized polystyrene latex particles was <span class="hlt">observed</span> using a high-speed video camera. The coalescence behavior was monitored as a function of oil type (n-dodecane versus sunflower oil) and particle size (135 versus 902 nm), as well as in the presence and absence of an oil-soluble cross-linker [tolylene 2,4-diisocyanate-terminated poly(propylene glycol)]. The damping coefficient of the coalescing n-dodecane droplets was found to increase in the presence of the latex, demonstrating particle adsorption. Coalescence times increased when the oil phase was changed from n-dodecane to sunflower oil, because of the much higher viscosity of the latter oil. In addition, increasing the adsorbed particle size from 135 to 902 nm led to longer coalescence times because of the greater distance separating the oil droplets. Coalescence times <span class="hlt">observed</span> in the presence of the larger 902-nm particles indicated that two different modes of contact can occur prior to a coalescence event (bilayer or bridging monolayer of particles in the film). Addition of an oil-soluble surface-active cross-linker to the sunflower oil phase to react with the hydroxy groups of the particle stabilizer reduced the interfacial elasticity and ultimately prevented coalescence after cross-linking for 20 min at 25 °C. Such giant colloidosomes can remain in contact for several hours without undergoing coalescence, which demonstrates their high stability. Furthermore, coalescence is prevented even if the cross-linker is present in only one of the pendant droplets. Finally, evidence for cross-linker diffusion from one pendant droplet to another was indicated by a visible filament connecting the two droplets upon retraction. PMID:23088251</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140005990','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140005990"><span id="translatedtitle">Extreme-Ultraviolet Spectroscopic <span class="hlt">Observation</span> of <span class="hlt">Direct</span> Coronal Heating During a C-Class Solar Flare</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Brosius, Jeffrey W.</p> <p>2012-01-01</p> <p>With the Coronal Diagnostic Spectrometer operating in rapid cadence (9.8 s) stare mode during a C6.6 flare on the solar disk, we <span class="hlt">observed</span> a sudden brightening of Fe xix line emission (formed at temperature T ˜ 8 MK) above the pre-flare noise without a corresponding brightening of emission from ions formed at lower temperatures, including He i (0.01 MK), Ov (0.25 MK), and Si xii (2 MK). The sudden brightening persisted as a plateau of Fe xix intensity that endured more than 11 minutes. The Fe xix emission at the rise and during the life of the plateau showed no evidence of significant bulk velocity flows, and hence cannot be attributed to chromospheric evaporation. However, the line width showed a significant broadening at the rise of the plateau, corresponding to nonthermal velocities of at least 89 km s-1 due to reconnection outflows or turbulence. During the plateau He i, Ov, and Si xii brightened at successively later times starting about 3.5 minutes after Fe xix, which suggests that these brightenings were produced by thermal conduction from the plasma that produced the Fe xix line emission; however, we cannot rule out the possibility that they were produced by a weak beam of nonthermal particles. We interpret an <span class="hlt">observed</span> shortening of the Ov wavelength for about 1.5 minutes toward the middle of the plateau to indicate new upward motions driven by the flare, as occurs during gentle chromospheric evaporation; relative to a quiescent interval shortly before the flare, the Ov upward velocity was around -10 km s-1.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21612900','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21612900"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of grafting interlayer phosphate in Mg/Al layered double hydroxides</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shimamura, Akihiro; Kanezaki, Eiji; Jones, Mark I.; Metson, James B.</p> <p>2012-02-15</p> <p>The grafting of interlayer phosphate in synthetic Mg/Al layered double hydroxides with interlayer hydrogen phosphate (LDH-HPO{sub 4}) has been studied by XRD, TG/DTA, FT-IR, XPS and XANES. The basal spacing of crystalline LDH-HPO{sub 4} decreases in two stages with increasing temperature, from 1.06 nm to 0.82 nm at 333 K in the first transition, and to 0.722 nm at 453 K in the second. The first stage occurs due to the loss of interlayer water and rearrangement of the interlayer HPO{sub 4}{sup 2-}. In the second transition, the interlayer phosphate is grafted to the layer by the formation of <span class="hlt">direct</span> bonding to metal cations in the layer, accompanied by a change in polytype of the crystalline structure. The grafted phosphate becomes immobilized and cannot be removed by anion-exchange with 1-octanesulfonate. The LDH is amorphous at 743 K but decomposes to Mg{sub 3}(PO{sub 4}){sub 2}, AlPO{sub 4}, MgO and MgAl{sub 2}O{sub 4} after heated to 1273 K. - Graphical abstract: The cross section of the synthetic Mg, Al layered double hydroxides in Phase 1, with interlayer hydrogen phosphate Phase 2, and with grafted phosphate, Phase 3. Highlights: Black-Right-Pointing-Pointer The grafting of hydrogen phosphate intercalated Mg/Al-LDH has been studied. Black-Right-Pointing-Pointer The basal spacing of crystalline LDH-HPO{sub 4} decreases in two stages with increasing temperature. Black-Right-Pointing-Pointer The first decrease is due to loss of interlayer water, the second is attributed to phosphate grafting. Black-Right-Pointing-Pointer The grafted interlayer phosphate becomes immobilized and cannot be removed by anion-exchange.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24704075','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24704075"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of ON and OFF pathways in the Drosophila visual system.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Strother, James A; Nern, Aljoscha; Reiser, Michael B</p> <p>2014-05-01</p> <p>Visual motion perception is critical to many animal behaviors, and flies have emerged as a powerful model system for exploring this fundamental neural computation. Although numerous studies have suggested that fly motion vision is governed by a simple neural circuit [1-3], the implementation of this circuit has remained mysterious for decades. Connectomics and neurogenetics have produced a surge in recent progress, and several studies have shown selectivity for light increments (ON) or decrements (OFF) in key elements associated with this circuit [4-7]. However, related studies have reached disparate conclusions about where this selectivity emerges and whether it plays a major role in motion vision [8-13]. To address these questions, we examined activity in the neuropil thought to be responsible for visual motion detection, the medulla, of Drosophila melanogaster in response to a range of visual stimuli using two-photon calcium imaging. We confirmed that the input neurons of the medulla, the LMCs, are not responsible for light-on and light-off selectivity. We then examined the pan-neural response of medulla neurons and found prominent selectivity for light-on and light-off in layers of the medulla associated with two anatomically derived pathways (L1/L2 associated) [14, 15]. We next examined the activity of prominent interneurons within each pathway (Mi1 and Tm1) and found that these neurons have corresponding selectivity for light-on or light-off. These results provide <span class="hlt">direct</span> evidence that motion is computed in parallel light-on and light-off pathways, demonstrate that this selectivity emerges in neurons immediately downstream of the LMCs, and specify where crucial elements of motion computation occur. PMID:24704075</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22199961','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22199961"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of unstained wet biological samples by scanning-electron generation X-ray microscopy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ogura, Toshihiko</p> <p>2010-01-01</p> <p>Analytical tools of nanometre-scale resolution are indispensable in the fields of biology, physics and chemistry. One suitable tool, the soft X-ray microscope, provides high spatial resolution of visible light for wet specimens. For biological specimens, X-rays of water-window wavelength between carbon (284 eV; 4.3 nm) and oxygen (540 eV; 2.3 nm) absorption edges provide high-contrast imaging of biological samples in water. Among types of X-ray microscope, the transmission X-ray microscope using a synchrotron radiation source with diffractive zone plates offers the highest spatial resolution, approaching 15-10 nm. However, even higher resolution is required to measure proteins and protein complexes in biological specimens; therefore, a new type of X-ray microscope with higher resolution that uses a simple light source is desirable. Here we report a novel scanning-electron generation X-ray microscope (SGXM) that demonstrates <span class="hlt">direct</span> imaging of unstained wet biological specimens. We deposited wet yeasts in the space between two silicon nitride (Si{sub 3}N{sub 4}) films. A scanning electron beam of accelerating voltage 5 keV and current 1.6 nA irradiates the titanium (Ti)-coated Si{sub 3}N{sub 4} film, and the soft X-ray signal from it is detected by an X-ray photodiode (PD) placed below the sample. The SGXM can theoretically achieve better than 5 nm resolution. Our method can be utilized easily for various wet biological samples of bacteria, viruses, and protein complexes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25637956','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25637956"><span id="translatedtitle">Quantifying the weight of fingerprint evidence through the spatial relationship, <span class="hlt">directions</span> and types of minutiae <span class="hlt">observed</span> on fingermarks.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Neumann, Cedric; Champod, Christophe; Yoo, Mina; Genessay, Thibault; Langenburg, Glenn</p> <p>2015-03-01</p> <p>This paper presents a statistical model for the quantification of the weight of fingerprint evidence. Contrarily to previous models (generative and score-based models), our model proposes to estimate the probability distributions of spatial relationships, <span class="hlt">directions</span> and types of minutiae <span class="hlt">observed</span> on fingerprints for any given fingermark. Our model is relying on an AFIS algorithm provided by 3M Cogent and on a dataset of more than 4,000,000 fingerprints to represent a sample from a relevant population of potential sources. The performance of our model was tested using several hundreds of minutiae configurations <span class="hlt">observed</span> on a set of 565 fingermarks. In particular, the effects of various sub-populations of fingers (i.e., finger number, finger general pattern) on the expected evidential value of our test configurations were investigated. The performance of our model indicates that the spatial relationship between minutiae carries more evidential weight than their type or <span class="hlt">direction</span>. Our results also indicate that the AFIS component of our model <span class="hlt">directly</span> enables us to assign weight to fingerprint evidence without the need for the additional layer of complex statistical modeling involved by the estimation of the probability distributions of fingerprint features. In fact, it seems that the AFIS component is more sensitive to the sub-population effects than the other components of the model. Overall, the data generated during this research project contributes to support the idea that fingerprint evidence is a valuable forensic tool for the identification of individuals. PMID:25637956</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.P53A1499F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.P53A1499F"><span id="translatedtitle">Apollo 11 and 16 Soil Bi-<span class="hlt">directional</span> Solar Reflectance Measurements, Models and LRO Diviner <span class="hlt">Observations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Foote, E. J.; Paige, D. A.; Shepard, M. K.; Johnson, J. R.; Biggar, S. F.; Greenhagen, B. T.; Allen, C.</p> <p>2010-12-01</p> <p>We have compared laboratory solar reflectance measurements of Apollo 11 and 16 soil samples to Lunar Reconnaissance Orbiter (LRO) Diviner orbital albedo measurements at the Apollo landing sites. The soil samples are two representative end member samples from the moon, low albedo lunar maria (sample 10084) and high albedo lunar highlands (sample 68810). Bidirectional reflectance distribution function (BRDF) measurements of the soil samples were conducted at Bloomsburg University (BUG) and at the University of Arizona [1,2]. We collected two different types of BUG datasets: a standard set of BRDF measurements at incidence angles of 0-60°, emission angles of 0-80°, and phase angles of 3-140°, and a high-incidence angle set of measurements along and perpendicular to the principal plane at incidence angles of 0-75° and phase angles of 3-155°. The BUG measurements generated a total of 765 data points in four different filters 450, 550, 750 and 950 nm. The Blacklab measurements were acquired at incidence angles of 60-88°, emission angles 60-82°, and phase angles of 17-93° at wavelengths of 455, 554, 699, 949nm. The BUG data were fit to two BRDF models: Hapke’s model [3] as described by Johnson et al, 2010 [4], and a simplified empirical function. The fact that both approaches can satisfactorily fit the BUG data is not unexpected, given the similarities between the functions and their input parameters, and the fact that the BRDF for dark lunar soil is dominated by the single scattering phase functions of the individual soil particles. To compare our lunar sample measurements with LRO Diviner data [5], we selected all daytime <span class="hlt">observations</span> acquired during the first year of operation within 3 km square boxes centered at the landing sites. We compared Diviner Channel 1 (0.3 - 3 µm) Lambert albedos with model calculated Lambert albedos of the lunar samples at the same photometric angles. In general, we found good agreement between the laboratory and Diviner measurements, particularly at intermediate incidence angles. We are currently reconciling any differences <span class="hlt">observed</span> between our two datasets to provide mutual validation, and to better understand the Diviner solar reflectance measurements in terms of lunar regolith properties. [1] Shepard, M.K., Solar System Remote Sensing Symposium, #4004, LPI, 2002; [2] Biggar, S.F. et al, Proc. Soc. Photo-Opt. Instrum. Eng. 924:232-240, 1988; [3] Hapke, B. Theory of Reflectance and Emittance Spectroscopy, Cambridge University Press, 1993; [4] Johnson J.R. et al, Fall AGU 2010; [5] Paige, D.A. et al, Space Science Reviews, 150:125-160, 2010;</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.5260P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.5260P"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of 1000m deep convection in the Irminger Sea by Argo-02 floats</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Piron, Anne; Mercier, Herlé; Thierry, Virginie; Caniaux, Guy</p> <p>2014-05-01</p> <p>Deep convection is an important process for intermediate and deep-water masses formation and for deep ocean ventilation. Deep convection is particularly important in the North Atlantic Ocean because it contributes at setting the density of the lower limb of the Meridional Overturning Circulation. The Labrador Sea is the most famous place in the North Atlantic Ocean where deep convection occurs, forming the intermediate Labrador Sea Water (LSW). Recent studies have suggested that the Irminger Sea is also a convection site where LSW could also be formed locally. Argo floats provide a regular sampling of the Irminger Sea since the early 2000s, in particular during the winter season. Thus, the Argo dataset provides opportunities to investigate, through a study of the winter mixed layers, whether deep convection in the Irminger Sea is isolated or occurs at a broad spatial scale firstly and to investigate local formation of LSW in the Irminger Sea secondly. The present analysis of Argo data highlights a deep convection event occurring in the Irminger Sea during winter 2011-2012. Intense convective activity at basin scale has been <span class="hlt">observed</span> for the first time in the Irminger Sea. From mid-January to mid-March, 31 Argo profiles exhibited a mixed layer depth exceeding 700m over a wide area located east of the southern tip of Greenland. Over the period 2002-2010, the deepest <span class="hlt">observed</span> mixed layers in the Irminger Sea did not exceed 600m, except for the winters 2007-2008 and 2008-2009 during which a few localized mixed layer depths reached 1000m. Among those 31 profiles, the mixed layer depth recorded by 4 different floats reached about 1000m, which is deep enough to feed the pool of LSW located in the Irminger Sea. A lagrangian study along the trajectory of those 4 floats, shows that there is a good agreement between heat loss at the air-sea interface and the heat content variations in the mixed layer. Those results clearly demonstrate that LSW was formed in the Irminger Sea in winter 2001-2012, which is further confirmed by oxygen data provided by one Argo float equipped with an oxygen sensor. Finally, the properties of the 2011-2012 LSW formed in the Irminger Sea are compared to those formed in the Labrador Sea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70019342','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70019342"><span id="translatedtitle"><span class="hlt">Directional</span> topographic site response at Tarzana <span class="hlt">observed</span> in aftershocks of the 1994 Northridge, California, earthquake: Implications for mainshock motions</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Spudich, P.; Hellweg, M.; Lee, W.H.K.</p> <p>1996-01-01</p> <p>The Northridge earthquake caused 1.78 g acceleration in the east-west <span class="hlt">direction</span> at a site in Tarzana, California, located about 6 km south of the mainshock epicenter. The accelerograph was located atop a hill about 15-m high, 500-m long, and 130-m wide, striking about N78??E. During the aftershock sequence, a temporary array of 21 three-component geophones was deployed in six radial lines centered on the accelerograph, with an average sensor spacing of 35 m. Station COO was located about 2 m from the accelerograph. We inverted aftershock spectra to obtain average relative site response at each station as a function of <span class="hlt">direction</span> of ground motion. We identified a 3.2-Hz resonance that is a transverse oscillation of the hill (a <span class="hlt">directional</span> topographic effect). The top/base amplification ratio at 3.2 Hz is about 4.5 for horizontal ground motions oriented approximately perpendicular to the long axis of the hill and about 2 for motions parallel to the hill. This resonance is seen most strongly within 50 m of COO. Other resonant frequencies were also <span class="hlt">observed</span>. A strong lateral variation in attenuation, probably associated with a fault, caused substantially lower motion at frequencies above 6 Hz at the east end of the hill. There may be some additional scattered waves associated with the fault zone and seen at both the base and top of the hill, causing particle motions (not spectral ratios) at the top of the hill to be rotated about 20?? away from the <span class="hlt">direction</span> transverse to the hill. The resonant frequency, but not the amplitude, of our <span class="hlt">observed</span> topographic resonance agrees well with theory, even for such a low hill. Comparisons of our <span class="hlt">observations</span> with theoretical results indicate that the 3D shape of the hill and its internal structure are important factors affecting its response. The strong transverse resonance of the hill does not account for the large east-west mainshock motions. Assuming linear soil response, mainshock east-west motions at the Tarzana accelerograph were amplified by a factor of about 2 or less compared with sites at the base of the hill. Probable variations in surficial shear-wave velocity do not account for the <span class="hlt">observed</span> differences among mainshock acceleration <span class="hlt">observed</span> at Tarzana and at two different sites within 2 km of Tarzana.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1509.08542.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1509.08542.pdf"><span id="translatedtitle">A Far-Infrared <span class="hlt">Observational</span> Test of the <span class="hlt">Directional</span> Dependence in Radiative Grain Alignment</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Vaillancourt, John E</p> <p>2015-01-01</p> <p>The alignment of interstellar dust grains with magnetic fields provides a key method for measuring the strength and morphology of the fields. In turn, this provides a means to study the role of magnetic fields from diffuse gas to dense star-forming regions. The physical mechanism for aligning the grains has been a long-term subject of study and debate. The theory of radiative torques, in which an anisotropic radiation field imparts sufficient torques to align the grains while simultaneously spinning them to high rotational velocities, has passed a number of <span class="hlt">observational</span> tests. Here we use archival polarization data in dense regions of the Orion molecular cloud (OMC-1) at 100, 350, and $850\\,\\mu$m to test the prediction that the alignment efficiency is dependent upon the relative orientations of the magnetic field and radiation anisotropy. We find that the expected polarization signal, with a 180-degree period, exists at all wavelengths out to radii of 1.5 arcminutes centered on the BNKL object in OMC-1. The ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1108.1256.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1108.1256.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of formation and propagation of subpolar eddies into the subtropical North Atlantic</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Bower, A S; Amrhein, D E; Lilly, J M</p> <p>2011-01-01</p> <p>Subsurface float and moored <span class="hlt">observations</span> are presented to show for the first time the formation and propagation of anticyclonic submesoscale coherent vortices that transport relatively cold, fresh subpolar water to the interior subtropical North Atlantic. Acoustically tracked RAFOS floats released in the southward-flowing Western Boundary Current at the exit of the Labrador Sea reveal the formation of three of these eddies at the southern tip of the Grand Banks (42 N, 50 W). Using a recently developed method to detect eddies in float trajectories and estimate their kinematic properties, it was found that the eddies had average rotation periods of 5--7 days at radii of 1025 km, with mean rotation speeds of up to 0.3 m/s. One especially long-lived (5.1 months) eddy crossed under the Gulf Stream path and translated southwestward in the subtropical recirculation to at least 35 N, where it hit one of the Corner Rise Seamounts. Velocity, temperature and salinity measurements from a nine-month deployment of two moor...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4142853','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4142853"><span id="translatedtitle"><span class="hlt">Direct</span> nanoscale <span class="hlt">observations</span> of the coupled dissolution of calcite and dolomite and the precipitation of gypsum</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cama, Jordi; Soler, Josep Maria; Putnis, Christine V</p> <p>2014-01-01</p> <p>Summary In-situ atomic force microscopy (AFM) experiments were performed to study the overall process of dissolution of common carbonate minerals (calcite and dolomite) and precipitation of gypsum in Na2SO4 and CaSO4 solutions with pH values ranging from 2 to 6 at room temperature (23 ± 1 °C). The dissolution of the carbonate minerals took place at the (104) cleavage surfaces in sulfate-rich solutions undersaturated with respect to gypsum, by the formation of characteristic rhombohedral-shaped etch pits. Rounding of the etch pit corners was <span class="hlt">observed</span> as solutions approached close-to-equilibrium conditions with respect to calcite. The calculated dissolution rates of calcite at pH 4.8 and 5.6 agreed with the values reported in the literature. When using solutions previously equilibrated with respect to gypsum, gypsum precipitation coupled with calcite dissolution showed short gypsum nucleation induction times. The gypsum precipitate quickly coated the calcite surface, forming arrow-like forms parallel to the crystallographic orientations of the calcite etch pits. Gypsum precipitation coupled with dolomite dissolution was slower than that of calcite, indicating the dissolution rate to be the rate-controlling step. The resulting gypsum coating partially covered the surface during the experimental duration of a few hours. PMID:25161860</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26437237','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26437237"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Highly Ordered Dendrimer Soft Building Blocks over a Large Area.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kwon, Kiok; Ok, Jong Min; Kim, Yun Ho; Kim, Jong-Seon; Jung, Woo-Bin; Cho, Soo-Yeon; Jung, Hee-Tae</p> <p>2015-11-11</p> <p>Developing large-area, single domain of organic soft-building blocks such as block copolymers, colloids, and supramolecular materials is one of the most important issues in the materials science and nanotechnology. Owing to their small sizes, complex molecular architectures, and high mobility, supramolecular materials are not well-suited for building large area, single domain structures. In the described study, a single domain of supramolecular columnar dendrimers was created over large area. The columnar structures in these domains have smaller (4.5 nm) diameters, higher area densities (ca. 36 Tera-dots/in(2)) and larger domains (>0.1 × 0.1 mm(2)) than those of all existing BCP and colloidal assemblies. By simply annealing dendrimer thin films between two flat solid surfaces, single domains of hexagonal columnar structures are created over large macroscopic areas. <span class="hlt">Observations</span> made in this effort should serve as the foundation for the design of new routes for bottom-up lithography based on supramolecular building blocks. PMID:26437237</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatPh..11..733L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatPh..11..733L"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of particle interactions and clustering in charged granular streams</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Victor; Waitukaitis, Scott R.; Miskin, Marc Z.; Jaeger, Heinrich M.</p> <p>2015-09-01</p> <p>Clustering of fine particles is of crucial importance in settings ranging from the early stages of planet formation to the coagulation of industrial powders and airborne pollutants. Models of such clustering typically focus on inelastic deformation and cohesion. However, even in charge-neutral particle systems comprising grains of the same dielectric material, tribocharging can generate large amounts of net positive or negative charge on individual particles, resulting in long-range electrostatic forces. The effects of such forces on cluster formation are not well understood and have so far not been studied in situ. Here we report the first <span class="hlt">observations</span> of individual collide-and-capture events between charged submillimetre particles, including Kepler-like orbits. Charged particles can become trapped in their mutual electrostatic energy well and aggregate via multiple bounces. This enables the initiation of clustering at relative velocities much larger than the upper limit for sticking after a head-on collision, a long-standing issue known from pre-planetary dust aggregation. Moreover, Coulomb interactions together with dielectric polarization are found to stabilize characteristic molecule-like configurations, providing new insights for the modelling of clustering dynamics in a wide range of microscopic dielectric systems, such as charged polarizable ions, biomolecules and colloids.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26352187','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26352187"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Very Large Zero-Field Splitting in a Tetrahedral Ni(II)Se4 Coordination Complex.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jiang, Shang-Da; Maganas, Dimitrios; Levesanos, Nikolaos; Ferentinos, Eleftherios; Haas, Sabrina; Thirunavukkuarasu, Komalavalli; Krzystek, J; Dressel, Martin; Bogani, Lapo; Neese, Frank; Kyritsis, Panayotis</p> <p>2015-10-14</p> <p>The high-spin (S = 1) tetrahedral Ni(II) complex [Ni{(i)Pr2P(Se)NP(Se)(i)Pr2}2] was investigated by magnetometry, spectroscopic, and quantum chemical methods. Angle-resolved magnetometry studies revealed the orientation of the magnetization principal axes. The very large zero-field splitting (zfs), D = 45.40(2) cm(-1), E = 1.91(2) cm(-1), of the complex was accurately determined by far-infrared magnetic spectroscopy, <span class="hlt">directly</span> <span class="hlt">observing</span> transitions between the spin sublevels of the triplet ground state. These are the largest zfs values ever determined-<span class="hlt">directly</span>-for a high-spin Ni(II) complex. Ab initio calculations further probed the electronic structure of the system, elucidating the factors controlling the sign and magnitude of D. The latter is dominated by spin-orbit coupling contributions of the Ni ions, whereas the corresponding effects of the Se atoms are remarkably smaller. PMID:26352187</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/15010520','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/15010520"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observations</span> of Daytime NO3: Implications for the Urban Boundary Layer Chemistry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Geyer, A.; Alicke, B.; Ackerman, Ralph; Martinez, M.; Harder, H.; Brune, W. H.; di Carlo, Piero; Williams, E. J.; Jobson, B Tom T.; Hall, Samual R.; Shetter, Richard E.; Stutz, Jochen P.</p> <p>2003-06-27</p> <p>The nitrate radical (NO3) is the dominant atmospheric oxidant during the night in most environments. During daytime, however, NO3 has thus far been undetected and considered insignificant. Here, we present the first daytime detection of NO3 by Differential Optical Absorption Spectroscopy near Houston, Texas during the Texas Air Quality Study 2000. On three consecutive days in August/September 2000, NO3 reached levels from » 5 ppt three hours before sunset to 31 ppt around sunset. Daytime NO3 has a negligible effect on the photostationary state (PSS) between O3 and NOx, with the exception of the last hour before sunset, when it significantly accelerates NO-to-NO2 conversion. On August 31 chemical reactions involving NO3 destroyed 8 (±4) ppb Ox (= O3 + NO2) during the day, and 27 (±6) ppb at night. NO3 chemistry contributed 10 (±7)% to the total Ox loss during the daytime, and 28% (±18%) integrated over a 24-hour period. It therefore plays an important role in the Ox budget. NO3 also contributed significantly to the daytime oxidation of hydrocarbons such as monoterpenes and phenol in Houston. The <span class="hlt">observed</span> daytime NO3 mixing ratios can be described as a function of O3 and NOx. Above NOx/O3 ratios of 3%, daytime NO3 becomes independent of NOx and proportional to the square of O3. Our calculations indicate that elevated (> 1ppt) NO3 levels are present whenever ozone mixing ratios exceed typical urban smog levels of 100 ppb.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007SPIE.6515E..1FF','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007SPIE.6515E..1FF"><span id="translatedtitle">Technology assessment: <span class="hlt">observer</span> study <span class="hlt">directly</span> compares screen/film to CR mammography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fletcher-Heath, Lynn; Richards, Anne; Ryan-Kron, Susan</p> <p>2007-03-01</p> <p>A new study supports and expands upon a previous reporting that computed radiography (CR) mammography offers as good, or better, image quality than state-of-the-art screen/film mammography. The suitability of CR mammography is explored through qualitative and quantitative study components: feature comparison and cancer detection rates of each modality. Images were collected from 150 normal and 50 biopsy-confirmed subjects representing a range of breast and pathology types. Comparison views were collected without releasing compression, using automatic exposure control on Kodak MIN-R films, followed by CR. Digital images were displayed as both softcopy (S/C) and hardcopy (H/C) for the feature comparison, and S/C for the cancer detection task. The qualitative assessment used preference scores from five board-certified radiologists obtained while viewing 100 screen/film-CR pairs from the cancer subjects for S/C and H/C CR output. Fifteen general image-quality features were rated, and up to 12 additional features were rated for each pair, based on the pathology present. Results demonstrate that CR is equivalent or preferred to conventional mammography for overall image quality (89% S/C, 95% H/C), image contrast (95% S/C, 98% H/C), sharpness (86% S/C, 93% H/C), and noise (94% S/C, 91% H/C). The quantitative objective was satisfied by asking 10 board-certified radiologists to provide a BI-RADS TM score and probability of malignancy per breast for each modality of the 200 cases. At least 28 days passed between <span class="hlt">observations</span> of the same case. Average sensitivity and specificity was 0.89 and 0.82 for CR and 0.91 and 0.82 for screen/film, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24897620','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24897620"><span id="translatedtitle">Detailed microscopic unfolding pathways of an ?-helix and a ?-hairpin: <span class="hlt">direct</span> <span class="hlt">observation</span> and molecular dynamics.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jas, Gouri S; Hegefeld, Wendy A; Middaugh, C Russell; Johnson, Carey K; Kuczera, Krzysztof</p> <p>2014-07-01</p> <p>We present a combined experimental and computational study of unfolding pathways of a model 21-residue ?-helical heteropeptide (W1H5-21) and a 16-residue ?-hairpin (GB41-56). Experimentally, we measured fluorescence energy transfer efficiency as a function of temperature, employing natural tryptophans as donors and dansylated lysines as acceptors. Secondary structural analysis was performed with circular dichroism and Fourier transform infrared spectroscopy. Our studies present markedly different unfolding pathways of the two elementary secondary structural elements. During thermal denaturation, the helical peptide exhibits an initial decrease in length, followed by an increase, while the hairpin undergoes a systematic increase in length. In the complementary computational part of the project, we performed microsecond length replica-exchange molecular dynamics simulations of the peptides in explicit solvent, yielding a detailed microscopic picture of the unfolding processes. For the ?-helical peptide, we found a large heterogeneous population of intermediates that are primarily frayed single helices or helix-turn-helix motifs. Unfolding starts at the termini and proceeds through a stable helical region in the interior of the peptide but shifted off-center toward the C-terminus. The simulations explain the experimentally <span class="hlt">observed</span> non-monotonic variation of helix length with temperature as due primarily to the presence of frayed-end single-helix intermediate structures. For the ?-hairpin peptide, our simulations indicate that folding is initiated at the turn, followed by formation of the hairpin in zipper-like fashion, with C?···C? contacts propagating from the turn to termini and hairpin hydrogen bonds forming in parallel with these contacts. In the early stages of hairpin formation, the hydrophobic side-chain contacts are only partly populated. Intermediate structures with low numbers of ?-hairpin hydrogen bonds have very low populations. This is in accord with the "broken zipper" model of Scheraga. The monotonic increase in length with temperature may be explained by the zipper-like breaking of the hairpin hydrogen bonds and backbone contacts. PMID:24897620</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1412169V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1412169V"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observations</span> of Magnetic Anomalies on the Lunar Surface under Varying Solar Wind Conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vorburger, A.; Wurz, P.; Barabash, S.; Wieser, M.; Futaana, Y.; Holmström, M.; Bhardwaj, A.; Dhanya, M. B.; Sridharan, R.; Asamura, K.</p> <p>2012-04-01</p> <p>In contrast to Earth, the Moon does not have a global dipolar magnetic field. Since the first lunar landing with Apollo 11, we know, though, that localised magnetic fields exist on the lunar surface. Measurements conducted by the Lunar Prospector magnetometer and electron reflectometer suggested that these localised magnetic fields are able to deflect the impinging solar wind in favourable cases (Lin et al., Science 1998). Magnetohydrodynamic simulations support the implication that mini-magnetospheres are formed above the locations of strong localised magnetic fields and can hold off the impinging solar wind (Harnett and Winglee, JGR 2002). Analysis of magnetic field data from Lunar Prospector of the Reiner Gamma anomaly region showed that the distortion of the magnetic field of this anomaly strongly depends on the impinging solar wind parameters, which was interpreted that the size and shape of the mini-magnetosphere changed with the solar wind parametes (Kurata et al., GRL 2005). Wieser et al., GRL 2010 showed that SARA, the Sub-KeV Atom Analyzer on board Chandrayaan-1, is able to detect an ENA image of the mini-magnetosphere in the measured energetic neutral atom flux. Here we analysed all orbits where CENA, the Chandrayaan-1 Energetic Neutral Analyzer, recorded data when a magnetic anomaly was in CENA's field-of-view. Our goal was to determine if 1) a signature of the magnetic anomaly is always visible in the ENA signal and if 2) there is a correlation between the solar wind dynamic pressure, the solar wind magnetic field, the local magnetic field strength and the reduction in the reflected ENA flux. Our results show that for the simplest case, i.e., the Gerasimovich anomaly, there is indeed a clear correlation between the shielding efficiency, the magnetic field strength and the solar wind dynamic pressure. For the other <span class="hlt">observed</span> magnetic anomalies, for which the magnetic fields are not only weaker but also spatially more variable than that of the Gerasimovich anomaly, only in about half of the cases such a correlation was found. We therefore conclude that the magnetic anomaly interaction is in general quite complex and that data with higher spatial resolution and more detailed modelling is required to understand this process better.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26514377','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26514377"><span id="translatedtitle">Hippocampal-dependent neurocognitive impairment following cranial irradiation <span class="hlt">observed</span> in pre-clinical models: current knowledge and possible future <span class="hlt">directions</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tomé, Wolfgang A; Gökhan, ?ölen; Gulinello, Maria E; Brodin, N Patrik; Heard, John; Mehler, Mark F; Guha, Chandan</p> <p>2016-01-01</p> <p>We reviewed the literature for studies pertaining to impaired adult neurogenesis leading to neurocognitive impairment following cranial irradiation in rodent models. This compendium was compared with respect to radiation dose, converted to equivalent dose in 2?Gy fractions (EQD2) to <span class="hlt">allow</span> for <span class="hlt">direct</span> comparison between studies. The effects of differences between animal species and the dependence on animal age as well as for time after irradiation were also considered. One of the major sites of de novo adult neurogenesis is the hippocampus, and as such, this review also focuses on assessing evidence related to the expression and potential effects of inflammatory cytokines on neural stem cells in the subgranular zone of the dentate gyrus and whether this correlates with neurocognitive impairment. This review also discusses potential strategies to mitigate the detrimental effects on neurogenesis and neurocognition resulting from cranial irradiation, and how the rationale for these strategies compares with the current outcome of pre-clinical studies. PMID:26514377</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23020575','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23020575"><span id="translatedtitle">Comparison of remote video and diver's <span class="hlt">direct</span> <span class="hlt">observations</span> to quantify reef fishes feeding on benthos in coral and rocky reefs.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Longo, G O; Floeter, S R</p> <p>2012-10-01</p> <p>This study compared remote underwater video and traditional <span class="hlt">direct</span> diver <span class="hlt">observations</span> to assess reef fish feeding impact on benthos across multiple functional groups within different trophic categories (e.g. herbivores, zoobenthivores and omnivores) and in two distinct reef systems: a subtropical rocky reef and a tropical coral reef. The two techniques were roughly equivalent, both detecting the species with higher feeding impact and recording similar bite rates, suggesting that reef fish feeding behaviour at the study areas are not strongly affected by the diver's presence. PMID:23020575</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1987MNRAS.226..173F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1987MNRAS.226..173F"><span id="translatedtitle">Aperture synthesis <span class="hlt">observations</span> of galactic atomic hydrogen in the <span class="hlt">direction</span> l=333.5 deg, b=-9,3</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Forster, J. R.; Whiteoak, J. B.; Kesteven, M. J.; Manchester, R. N.; Rayner, P. T.; Ables, J. G.; Peters, W. L.</p> <p>1987-05-01</p> <p>Galactic atomic hydrogen has been mapped with the Parkes two-element synthesis telescope (TEST) in the <span class="hlt">direction</span> l = 333°.5, b = -0°.3. H I structure on a large angular scale is probed using absorption measurements toward eight compact continuum sources scattered over an area 25 arcmin across. The detailed H I absorption over the extended (4 arcmin) H II region G 333.6-0.2 is mapped with 39×56 arcsec resolution. Various explanations for the 'anomalous' high-velocity gas associated with G 333.3-0.4 are considered in the light of the <span class="hlt">observations</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1102.3356v2','EPRINT'); return false;" href="http://arxiv.org/pdf/1102.3356v2"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> and Analysis of Spin Dependent Transport of Single Atoms in a 1D Optical Lattice</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Micha? Karski; Leonid Förster; Jai-Min Choi; Andrea Alberti; Wolfgang Alt; Artur Widera; Dieter Meschede</p> <p>2011-11-15</p> <p>We have <span class="hlt">directly</span> <span class="hlt">observed</span> spin-dependent transport of single cesium atoms in a 1D optical lattice. A superposition of two circularly polarized standing waves is generated from two counter propagating, linearly polarized laser beams. Rotation of one of the polarizations by $\\pi$ causes displacement of the $\\sigma^{+}$- and $\\sigma^{-}$-lattices by one lattice site. Unidirectional transport over several lattice sites is achieved by rotating the polarization back and forth and flipping the spin after each transport step. We have analyzed the transport efficiency over 10 and more lattice sites, and discussed and quantified relevant error sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://oaktrust.library.tamu.edu//handle/1969.1/126522','EPRINT'); return false;" href="http://oaktrust.library.tamu.edu//handle/1969.1/126522"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Hyperfine Quenching of the (2)3p0 Level in Helium-Like Nickel </span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Dunford, R. W.; Liu, C. J.; Last, J.; Berrahmansour, N.; Vondrasek, R.; Church, David A.; Curtis, L. J.</p> <p>1991-01-01</p> <p>VOLUME 44, NUMBER 1 I JULY 1991 <span class="hlt">Direct</span> <span class="hlt">observation</span> of hyperfine quenching of the 2 I'o level in heliumlike nickel R. W. Dunford, C. J. Liu, J. Last, N. Berrah-Mansour, and R. Vondrasek Physics Division, Argonne National Laboratory, Argonne, Illinois...~+ are given by 8'? = ?0.0109 eV, W&0 = ?0.0057 eV, I 0=2.640X 10 eV I ) =0.0518 eV. [14] R. W. Dunford, M. Hass, E. Bakke, H. G. Berry, C. J. Liu, M. L. A. Raphaelian, and L. J. Curtis, Phys. Rev. Lett. 62, 2809 (1989). [15]R. Marrus, P. Charles, P...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/564252','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/564252"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of atomic structures of defects in GaN by high-resolution Z-contrast STEM</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xin, Y. |; Pennycook, S.J.; Browning, N.D.; Sivananthan, S.; Nellist, P.D.; Faurie, J.P. |; Gibart, P.</p> <p>1997-12-01</p> <p>GaN/(0001) Sapphire grown by low pressure MOVPE is studied by high resolution Z-contrast imaging using STEM. First <span class="hlt">direct</span> <span class="hlt">observation</span> of the threading dislocation with edge character shows the atomic core structure, which appears to have a similar configuration to the {l_brace}10-10{r_brace} surface. The surfaces of the nanopipe walls are on {l_brace}10-10{r_brace} with the terminating layer between the atoms with one bond per pair. In addition, the high resolution Z contrast image of the prismatic stacking fault confirms the results by conventional HRTEM.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15768346','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15768346"><span id="translatedtitle">Use of community-based, <span class="hlt">directly</span> <span class="hlt">observed</span> therapy for HIV infection: lessons learned for treatment of hepatitis C virus infection.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Flanigan, Timothy P; Taylor, Lynn E; Mitty, Jennifer A</p> <p>2005-04-15</p> <p><span class="hlt">Directly</span> <span class="hlt">observed</span> therapy (DOT) is an effective approach for the treatment of tuberculosis among substance users. We have adapted this model to treat human immunodeficiency virus infection. Our experience suggests that community-based, modified DOT should be explored further as a means to treat infectious diseases and chronic medical illnesses for persons with drug dependence; it may be especially pertinent for the treatment of hepatitis C virus infection. DOT can both optimize adherence and provide a way to offer psychosocial support and linkages to social, addiction, psychiatric, and other services, to help address many of the challenges faced by persons with substance abuse disorders. PMID:15768346</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12960835','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12960835"><span id="translatedtitle"><span class="hlt">Directly</span> <span class="hlt">observed</span> antiretroviral therapy to reduce genital tract and plasma HIV-1 RNA in women with poor adherence.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Harwell, Joseph I; Flanigan, Timothy P; Mitty, Jennifer A; Macalino, Grace E; Caliendo, Angela M; Ingersoll, Jessica; Stenzel, Molly S; Carpenter, Charles C J; Cu-Uvin, Susan</p> <p>2003-09-01</p> <p>Six women with substance abuse and poor adherence histories received daily antiretroviral <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (DOT). Cervicovaginal lavage (CVL) and plasma HIV-1-RNA levels were measured at baseline, 1 month, 3 months, and 6 months. All subjects had undetectable (below 2.6 log10 copies/ml) CVL HIV-1-RNA levels by 3 months and undetectable plasma HIV-1-RNA levels by 6 months. The mean CD4 cell increase was 76 cells/mm3. DOT appears effective and may reduce infectiousness in this high-risk population. PMID:12960835</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JNuM..467..155R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JNuM..467..155R"><span id="translatedtitle">Effect of Gallium ion damage on poly-crystalline Zirconium: <span class="hlt">Direct</span> experimental <span class="hlt">observations</span> and molecular dynamics simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Revelly, A. K.; Monpara, G.; Samajdar, I.; Krishna, K. V. Mani; Tewari, R.; Srivastava, D.; Dey, G. K.; Panwar, A. S.</p> <p>2015-12-01</p> <p>This study involved controlled focused ion beam (FIB) damage of high purity poly-crystalline Zirconium (Zr) and EBSD (electron backscattered diffraction) <span class="hlt">observations</span> on the same region/microstructure. <span class="hlt">Direct</span> experimental <span class="hlt">observations</span> were augmented by molecular dynamics (MD) simulations: the latter demonstrating a hierarchy of microstructural features enabling/retarding relative ion damage. Experimental results clearly established a non-monotonic dependence of damage kinetics with average grain size. Damage increased with grain size, till an average grain size of 12 micron, and then dropped. This was explained from combined effects of grain size and in-grain misorientations. For lower than 12 micron average grain size, noticeable in-grain misorientations enabled lower damage kinetics. For greater than 17 micron grain size, with insignificant in-grain misorientations, reduced presence of high angle grain boundaries were shown to retard relative ion damage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/538366','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/538366"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of the amphoteric behavior of Ge in InP modified by P co-implantation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yu, K.M.; Ridgway, M.C.</p> <p>1997-08-01</p> <p>We have investigated the preferred substitution of Ge in InP by altering the local stoichiometry of the InP substrate. By co-implanting P with Ge to create a group V-rich environment, we <span class="hlt">directly</span> <span class="hlt">observed</span> an enhancement of the Ge substituting the In sublattice. A corresponding increase in the n-type conductivity by as much as three times was also <span class="hlt">observed</span> in the Ge and P co-implanted sample. However, due to the altered local stoichiometry, the Ge solubility in InP was reduced by a factor of 2. The residual crystalline damage in the P co-implanted InP after annealing was also decreased due to the compensation of the nonstoichiometry related damage by the excess P in the middle of the implanted region. {copyright} {ital 1997 American Institute of Physics.}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3273783','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3273783"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of crystal defects in an organic molecular crystals of copper hexachlorophthalocyanine by STEM-EELS</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Haruta, Mitsutaka; Kurata, Hiroki</p> <p>2012-01-01</p> <p>The structural analysis of crystal defects in organic thin films provides fundamental insights into their electronic properties for applications such as field effect transistors. <span class="hlt">Observation</span> of crystal defects in organic thin films has previously been performed at rather low resolution by conventional transmission electron microscopy based on phase-contrast imaging. Herein, we apply for the first time annular dark-field imaging to the <span class="hlt">direct</span> <span class="hlt">observation</span> of grain boundaries in copper hexachlorophthalocyanine thin films at the atomic resolution level by using an aberration-corrected scanning transmission electron microscope combined with electron energy-loss spectroscopy. By using a low-dose technique and an optimized detection angle, we were able to visualize the contrast of light element (C and N) together with the heavier elements (Cl and Cu) within the molecular column. We were also able to identify unexpected molecular orientations in the grain boundaries along the {110} crystallographic planes giving rise to stacking faults. PMID:22355764</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26113719','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26113719"><span id="translatedtitle">HIGH-PRESSURE PHYSICS. <span class="hlt">Direct</span> <span class="hlt">observation</span> of an abrupt insulator-to-metal transition in dense liquid deuterium.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Knudson, M D; Desjarlais, M P; Becker, A; Lemke, R W; Cochrane, K R; Savage, M E; Bliss, D E; Mattsson, T R; Redmer, R</p> <p>2015-06-26</p> <p>Eighty years ago, it was proposed that solid hydrogen would become metallic at sufficiently high density. Despite numerous investigations, this transition has not yet been experimentally <span class="hlt">observed</span>. More recently, there has been much interest in the analog of this predicted metallic transition in the dense liquid, due to its relevance to planetary science. Here, we show <span class="hlt">direct</span> <span class="hlt">observation</span> of an abrupt insulator-to-metal transition in dense liquid deuterium. Experimental determination of the location of this transition provides a much-needed benchmark for theory and may constrain the region of hydrogen-helium immiscibility and the boundary-layer pressure in standard models of the internal structure of gas-giant planets. PMID:26113719</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..MAR.Z7011X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..MAR.Z7011X"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of the Bandwidth Control Mott Transition in the NiS2-xSex Multiband System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, H. C.; Zhang, Y.; Xu, M.; Peng, R.; Shen, X. P.; Strocov, V. N.; Shi, M.; Kobayashi, M.; Schmitt, T.; Xie*, B. P.; Feng*, D. L.</p> <p>2015-03-01</p> <p>The bulk electronic structure of NiS2-xSex has been studied across the bandwidth-control Mott transition (BCMT) using soft x-ray angle-resolved photoemission spectroscopy. We show that Se doping does not alter the Fermi surface volume. When approaching the insulating phase with decreasing Se concentration, we <span class="hlt">observed</span> that the Fermi velocity continuously decreases. Meanwhile, the weight of the coherent quasiparticle, which sits on a large incoherent spectrum, continuously decreases and is transferred to higher binding energies, until it suddenly disappears across the Mott transition. In the insulating phase, there is still finite spectral weight at the Fermi energy, but it is incoherent and dispersionless due to strong correlations. Our results provide a <span class="hlt">direct</span> <span class="hlt">observation</span> of the distinct characters of BCMT in a multiband non-half-filled system.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120010093','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120010093"><span id="translatedtitle">Remote and In Situ <span class="hlt">Observations</span> of an Unusual Earth-<span class="hlt">Directed</span> Coronal Mass Ejection from Multiple Viewpoints</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nieves-Chinchilla, T.; Colaninno, R.; Vourlidas, A.; Szabo, A.; Lepping, R. P.; Boardsen, S. A.; Anderson, B. J.; Korth, H.</p> <p>2012-01-01</p> <p>During June 16-21, 2010, an Earth-<span class="hlt">directed</span> Coronal Mass Ejection (CME) event was <span class="hlt">observed</span> by instruments onboard STEREO, SOHO, MESSENGER and Wind. This event was the first <span class="hlt">direct</span> detection of a rotating CME in the middle and outer corona. Here, we carry out a comprehensive analysis of the evolution of the CME in the interplanetary medium comparing in-situ and remote <span class="hlt">observations</span>, with analytical models and three-dimensional reconstructions. In particular, we investigate the parallel and perpendicular cross section expansion of the CME from the corona through the heliosphere up to 1 AU. We use height-time measurements and the Gradual Cylindrical Shell (GCS) technique to model the imaging <span class="hlt">observations</span>, remove the projection effects, and derive the 3-dimensional extent of the event. Then, we compare the results with in-situ analytical Magnetic Cloud (MC) models, and with geometrical predictions from past works. We nd that the parallel (along the propagation plane) cross section expansion agrees well with the in-situ model and with the Bothmer & Schwenn [1998] empirical relationship based on in-situ <span class="hlt">observations</span> between 0.3 and 1 AU. Our results effectively extend this empirical relationship to about 5 solar radii. The expansion of the perpendicular diameter agrees very well with the in-situ results at MESSENGER ( 0:5 AU) but not at 1 AU. We also find a slightly different, from Bothmer & Schwenn [1998], empirical relationship for the perpendicular expansion. More importantly, we find no evidence that the CME undergoes a significant latitudinal over-expansion as it is commonly assumed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24625741','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24625741"><span id="translatedtitle">A new <span class="hlt">direct</span> single-molecule <span class="hlt">observation</span> method for DNA synthesis reaction using fluorescent replication protein A.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Takahashi, Shunsuke; Kawasaki, Shohei; Miyata, Hidefumi; Kurita, Hirofumi; Mizuno, Takeshi; Matsuura, Shun-ichi; Mizuno, Akira; Oshige, Masahiko; Katsura, Shinji</p> <p>2014-01-01</p> <p>Using a single-stranded region tracing system, single-molecule DNA synthesis reactions were <span class="hlt">directly</span> <span class="hlt">observed</span> in microflow channels. The <span class="hlt">direct</span> single-molecule <span class="hlt">observations</span> of DNA synthesis were labeled with a fusion protein consisting of the ssDNA-binding domain of a 70-kDa subunit of replication protein A and enhanced yellow fluorescent protein (RPA-YFP). Our method was suitable for measurement of DNA synthesis reaction rates with control of the ss?DNA form as stretched ss?DNA (+flow) and random coiled ss?DNA (-flow) via buffer flow. Sequentially captured photographs demonstrated that the synthesized region of an ss?DNA molecule monotonously increased with the reaction time. The DNA synthesis reaction rate of random coiled ss?DNA (-flow) was nearly the same as that measured in a previous ensemble molecule experiment (52 vs. 50 bases/s). This suggested that the random coiled form of DNA (-flow) reflected the DNA form in the bulk experiment in the case of DNA synthesis reactions. In addition, the DNA synthesis reaction rate of stretched ss?DNA (+flow) was approximately 75% higher than that of random coiled ss?DNA (-flow) (91 vs. 52 bases/s). The DNA synthesis reaction rate of the Klenow fragment (3'-5'exo-) was promoted by DNA stretching with buffer flow. PMID:24625741</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17948786','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17948786"><span id="translatedtitle">Monte Carlo simulations derived from <span class="hlt">direct</span> <span class="hlt">observations</span> of individual bacteria inform macroscopic migration models at granular porous media interfaces.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kusy, Kevin; Ford, Roseanne M</p> <p>2007-09-15</p> <p>Motile bacteria accumulated at the interface between an aqueous solution and a polymer gel suspension. The gel suspension was produced using Gelrite and contained 50-500 microm semisolid gel particulates in aqueous buffer. Smooth-swimming (HCB437) and wild-type (HCB1) Escherchia coli displayed normal swimming behaviors in the aqueous buffer but exhibited no translational motion when obstructed by the semisolid particulates of the gel suspension. Translational motion immediately resumed after the bacteria reoriented in a <span class="hlt">direction</span> away from the particle surfaces. These <span class="hlt">observations</span> were incorporated into Monte Carlo simulations that linked individual swimming properties to macroscopic bacterial distributions. The simulations suggested that the apparent surface area of the porous media influenced the degree of bacteria/surface interactions and thatthe mechanism of surface association could concentrate bacterial populations based upon the physical constraints of the porous media system. Population distributions from the Monte Carlo simulations matched a 1-D transport model that characterized the bacteria/surface interactions as an adsorption-like process even though <span class="hlt">direct</span> <span class="hlt">observations</span> suggested no physical attachment was occurring. Consequently, the 1-D transport model provided a semiquantitative approach to approximate bacterial migrations within porous media systems. Results suggest that the self-propulsive nature of bacteria can produce nondiffusive migration patterns within high-surface area environments. PMID:17948786</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4067821','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4067821"><span id="translatedtitle">What keeps family physicians busy in Portugal? A multicentre <span class="hlt">observational</span> study of work other than <span class="hlt">direct</span> patient contacts</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Granja, Mónica; Ponte, Carla; Cavadas, Luís Filipe</p> <p>2014-01-01</p> <p>Objectives To quantify the time spent by family physicians (FP) on tasks other than <span class="hlt">direct</span> patient contact, to evaluate job satisfaction, to analyse the association between time spent on tasks and physician characteristics, the association between the number of tasks performed and physician characteristics and the association between time spent on tasks and job satisfaction. Design Cross-sectional, using time-and-motion techniques. Two workdays were documented by <span class="hlt">direct</span> <span class="hlt">observation</span>. A significance level of 0.05 was adopted. Setting Multicentric in 104 Portuguese family practices. Participants A convenience sample of FP, with lists of over 1000 patients, teaching senior medical students and first-year family medicine residents in 2012, was obtained. Of the 217 FP invited to participate, 155 completed the study. Main outcomes measured Time spent on tasks other than <span class="hlt">direct</span> patient contact and on the performance of more than one task simultaneously, the number of <span class="hlt">direct</span> patient contacts in the office, the number of indirect patient contacts, job satisfaction, demographic and professional characteristics associated with time spent on tasks and the number of different tasks performed, and the association between time spent on tasks and job satisfaction. Results FP (n=155) spent a mean of 143.6?min/day (95% CI 135.2 to 152.0) performing tasks such as prescription refills, teaching, meetings, management and communication with other professionals (33.4% of their workload). FP with larger patient lists spent less time on these tasks (p=0.002). Older FP (p=0.021) and those with larger lists (p=0.011) performed fewer tasks. The mean job satisfaction score was 3.5 (out of 5). No association was found between job satisfaction and time spent on tasks. Conclusions FP spent one-third of their workday in coordinating care, teaching and managing. Time devoted to these tasks decreases with increasing list size and physician age. PMID:24934208</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25346189','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25346189"><span id="translatedtitle">Population genetic structure and <span class="hlt">direct</span> <span class="hlt">observations</span> reveal sex-reversed patterns of dispersal in a cooperative bird.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Harrison, Xavier A; York, Jennifer E; Young, Andrew J</p> <p>2014-12-01</p> <p>Sex-biased dispersal is pervasive and has diverse evolutionary implications, but the fundamental drivers of dispersal sex biases remain unresolved. This is due in part to limited diversity within taxonomic groups in the <span class="hlt">direction</span> of dispersal sex biases, which leaves hypothesis testing critically dependent upon identifying rare reversals of taxonomic norms. Here, we use a combination of <span class="hlt">observational</span> and genetic data to demonstrate a rare reversal of the avian sex bias in dispersal in the cooperatively breeding white-browed sparrow weaver (Plocepasser mahali). <span class="hlt">Direct</span> <span class="hlt">observations</span> revealed that (i) natal philopatry was rare, with both sexes typically dispersing locally to breed, and (ii), unusually for birds, males bred at significantly greater distances from their natal group than females. Population genetic analyses confirmed these patterns, as (i) corrected Assignment index (AIc), FST tests and isolation-by-distance metrics were all indicative of longer dispersal distances among males than females, and (ii) spatial autocorrelation analysis indicated stronger within-group genetic structure among females than males. Examining the spatial scale of extra-group mating highlighted that the resulting 'sperm dispersal' could have acted in concert with individual dispersal to generate these genetic patterns, but gamete dispersal alone cannot account entirely for the sex differences in genetic structure <span class="hlt">observed</span>. That leading hypotheses for the evolution of dispersal sex biases cannot readily account for these sex-reversed patterns of dispersal in white-browed sparrow weavers highlights the continued need for attention to alternative explanations for this enigmatic phenomenon. We highlight the potential importance of sex differences in the distances over which dispersal opportunities can be detected. PMID:25346189</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4265262','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4265262"><span id="translatedtitle">Population genetic structure and <span class="hlt">direct</span> <span class="hlt">observations</span> reveal sex-reversed patterns of dispersal in a cooperative bird</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Harrison, Xavier A; York, Jennifer E; Young, Andrew J</p> <p>2014-01-01</p> <p>Sex-biased dispersal is pervasive and has diverse evolutionary implications, but the fundamental drivers of dispersal sex biases remain unresolved. This is due in part to limited diversity within taxonomic groups in the <span class="hlt">direction</span> of dispersal sex biases, which leaves hypothesis testing critically dependent upon identifying rare reversals of taxonomic norms. Here, we use a combination of <span class="hlt">observational</span> and genetic data to demonstrate a rare reversal of the avian sex bias in dispersal in the cooperatively breeding white-browed sparrow weaver (Plocepasser mahali). <span class="hlt">Direct</span> <span class="hlt">observations</span> revealed that (i) natal philopatry was rare, with both sexes typically dispersing locally to breed, and (ii), unusually for birds, males bred at significantly greater distances from their natal group than females. Population genetic analyses confirmed these patterns, as (i) corrected Assignment index (AIc), FST tests and isolation-by-distance metrics were all indicative of longer dispersal distances among males than females, and (ii) spatial autocorrelation analysis indicated stronger within-group genetic structure among females than males. Examining the spatial scale of extra-group mating highlighted that the resulting ‘sperm dispersal’ could have acted in concert with individual dispersal to generate these genetic patterns, but gamete dispersal alone cannot account entirely for the sex differences in genetic structure <span class="hlt">observed</span>. That leading hypotheses for the evolution of dispersal sex biases cannot readily account for these sex-reversed patterns of dispersal in white-browed sparrow weavers highlights the continued need for attention to alternative explanations for this enigmatic phenomenon. We highlight the potential importance of sex differences in the distances over which dispersal opportunities can be detected. PMID:25346189</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16044005','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16044005"><span id="translatedtitle">The use of community-based modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy for the treatment of HIV-infected persons.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mitty, Jennifer A; Macalino, Grace E; Bazerman, Lauri B; Loewenthal, Helen G; Hogan, Joseph W; MacLeod, Cynthia J; Flanigan, Timothy P</p> <p>2005-08-15</p> <p><span class="hlt">Directly</span> <span class="hlt">observed</span> therapy, which has been successful in the treatment of tuberculosis, is being adapted for the treatment of HIV to decrease long-term morbidity and mortality. We describe the experiences of 69 HIV-infected individuals who were enrolled in a community-based modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (MDOT) program. Participants were referred by their primary care physicians based on nonadherence to antiretroviral therapy, and/or active substance use. A near-peer outreach worker initially delivered medications to participants 5 to 7 days per week, with visits subsequently tapered to 1 to 3 days per week after 3 or more months. Questionnaires were completed and laboratory values were obtained at baseline, 1 month, and every 3 months after enrollment. At enrollment, 96% of participants had a history of substance use, 71% had a history of incarceration, and 93% were experienced with highly active antiretroviral therapy (HAART). At the time of their 6-month assessment visit, 31 of 69 participants were receiving <span class="hlt">observed</span> therapy visits. The median baseline plasma viral load (PVL) was 4.8 log, and the median individual change in PVL from baseline to 6 months among participants receiving MDOT was a decrease of 2.7 log. Reasons why participants were not receiving visits included medication holidays, hospitalization or assisted living, incarceration, discontinuation of program involvement, and death. These results support that MDOT should be included in the spectrum of options available to enhance adherence to HAART among patients who are unsuccessful with self-administration of their medications. PMID:16044005</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20150004550&hterms=group+technology&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dgroup%2Btechnology','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20150004550&hterms=group+technology&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dgroup%2Btechnology"><span id="translatedtitle">Research and Development of External Occultor Technology for the <span class="hlt">Direct</span> <span class="hlt">Observation</span> of Extrasolar Planetary Systems : JPL Starshades Project</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Franz, Herbert; Stadeler, Mehnert</p> <p>2012-01-01</p> <p>Our group conducted work during the Summer of 2012 assembling and developing JPL's Starshades Project under the Technology Development for Exoplanet Missions(TDEM) initiative created by NASA, specifically TDEM stage 2. The goal of the work conducted at JPL by our group was to construct four occultor petals, the main optical components of the Starshade, for the analysis of joint deployment characteristics and of mechanical strain. A Starshade is an optical structure measuring approximately 30 meters in diameter that uses the effects of light diffraction off sheer edges, light scattering, and negative interference between waves to negate all on-axis light in a telescope's image, providing very high contrast that <span class="hlt">allows</span> planets orbiting a target star to be <span class="hlt">observed</span>. We completed our engineering goals in the time span of 10 weeks, during which the assembly processes of manufacture, alignment, and structural bonding took place. The Starshade technology and construction process is further discussed in the body of this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRA..120.4519Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRA..120.4519Z"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observations</span> of the full Dungey convection cycle in the polar ionosphere for southward interplanetary magnetic field conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Q.-H.; Lockwood, M.; Foster, J. C.; Zhang, S.-R.; Zhang, B.-C.; McCrea, I. W.; Moen, J.; Lester, M.; Ruohoniemi, J. M.</p> <p>2015-06-01</p> <p>Tracking the formation and full evolution of polar cap ionization patches in the polar ionosphere, we <span class="hlt">directly</span> <span class="hlt">observe</span> the full Dungey convection cycle for southward interplanetary magnetic field (IMF) conditions. This enables us to study how the Dungey cycle influences the patches' evolution. The patches were initially segmented from the dayside storm enhanced density plume at the equatorward edge of the cusp, by the expansion and contraction of the polar cap boundary due to pulsed dayside magnetopause reconnection, as indicated by in situ Time History of Events and Macroscale Interactions during Substorms (THEMIS) <span class="hlt">observations</span>. Convection led to the patches entering the polar cap and being transported antisunward, while being continuously monitored by the globally distributed arrays of GPS receivers and Super Dual Auroral Radar Network radars. Changes in convection over time resulted in the patches following a range of trajectories, each of which differed somewhat from the classical twin-cell convection streamlines. Pulsed nightside reconnection, occurring as part of the magnetospheric substorm cycle, modulated the exit of the patches from the polar cap, as confirmed by coordinated <span class="hlt">observations</span> of the magnetometer at Tromsø and European Incoherent Scatter Tromsø UHF radar. After exiting the polar cap, the patches broke up into a number of plasma blobs and returned sunward in the auroral return flow of the dawn and/or dusk convection cell. The full circulation time was about 3 h.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24943003','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24943003"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of lattice symmetry breaking at the hidden-order transition in URu2Si2.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tonegawa, S; Kasahara, S; Fukuda, T; Sugimoto, K; Yasuda, N; Tsuruhara, Y; Watanabe, D; Mizukami, Y; Haga, Y; Matsuda, T D; Yamamoto, E; Onuki, Y; Ikeda, H; Matsuda, Y; Shibauchi, T</p> <p>2014-01-01</p> <p>Since the 1985 discovery of the phase transition at THO=17.5 K in the heavy-fermion metal URu2Si2, neither symmetry change in the crystal structure nor large magnetic moment that can account for the entropy change has been <span class="hlt">observed</span>, which makes this hidden order enigmatic. Recent high-field experiments have suggested electronic nematicity that breaks fourfold rotational symmetry, but <span class="hlt">direct</span> evidence has been lacking for its ground state in the absence of magnetic field. Here we report on the <span class="hlt">observation</span> of lattice symmetry breaking from the fourfold tetragonal to twofold orthorhombic structure by high-resolution synchrotron X-ray diffraction measurements at zero field, which pins down the space symmetry of the order. Small orthorhombic symmetry-breaking distortion sets in at THO with a jump, uncovering the weakly first-order nature of the hidden-order transition. This distortion is <span class="hlt">observed</span> only in ultrapure samples, implying a highly unusual coupling nature between the electronic nematicity and underlying lattice. PMID:24943003</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22300129','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22300129"><span id="translatedtitle"><span class="hlt">Observation</span> of early shell-dopant mix in OMEGA <span class="hlt">direct</span>-drive implosions and comparisons with radiation-hydrodynamic simulations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Baumgaertel, J. A.; Bradley, P. A.; Hsu, S. C.; Cobble, J. A.; Hakel, P.; Tregillis, I. L.; Krasheninnikova, N. S.; Murphy, T. J.; Schmitt, M. J.; Shah, R. C.; Obrey, K. D.; Batha, S.; Johns, H.; Joshi, T.; Mayes, D.; Mancini, R. C.; Nagayama, T.</p> <p>2014-05-15</p> <p>Temporally, spatially, and spectrally resolved x-ray image data from <span class="hlt">direct</span>-drive implosions on OMEGA were interpreted with the aid of radiation-hydrodynamic simulations. Neither clean calculations nor those using a turbulent mix model can explain fully the <span class="hlt">observed</span> migration of shell-dopant material (titanium) into the core. Shell-dopant migration was <span class="hlt">observed</span> via time-dependent, spatially integrated spectra, and spatially and spectrally resolved x-ray images of capsule implosions and resultant dopant emissions. The titanium emission was centrally peaked in narrowband x-ray images. In post-processed clean simulations, the peak titanium emission forms in a ring in self-emission images as the capsule implodes. Post-processed simulations with mix reproduce trends in time-dependent, spatially integrated spectra, as well having centrally peaked Ti emission in synthetic multiple monochromatic imager. However, mix simulations still do not transport Ti to the core as is <span class="hlt">observed</span> in the experiment. This suggests that phenomena in addition to the turbulent mix must be responsible for the transport of Ti. Simple diffusion estimates are unable to explain the early Ti mix into the core. Mechanisms suggested for further study are capsule surface roughness, illumination non-uniformity, and shock entrainment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22255100','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22255100"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of adsorption geometry for the van der Waals adsorption of a single ?-conjugated hydrocarbon molecule on Au(111)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kim, Ju-Hyung; Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 ; Jung, Jaehoon; Kim, Yousoo E-mail: ykim@riken.jp; Tahara, Kazukuni; Tobe, Yoshito E-mail: ykim@riken.jp; Kawai, Maki E-mail: ykim@riken.jp</p> <p>2014-02-21</p> <p>Weak van der Waals adsorption of ?-conjugated hydrocarbon molecules onto the gold surface, Au(111), is one of the essential processes in constructing organic-metal interfaces in organic electronics. Here we provide a first <span class="hlt">direct</span> <span class="hlt">observation</span> of adsorption geometry of a single ?-conjugated hydrocarbon molecule on Au(111) using an atomically resolved scanning tunneling microscopy study combined with van der Waals density functional methodology. For the purpose, we utilized a highly symmetric ?-conjugated hydrocarbon molecule, dehydrobenzo[12]annulene (DBA), which has a definite three-fold symmetry, the same as the Au(111) surface. Interestingly, our <span class="hlt">observations</span> on an atomically resolved scale clearly indicate that the DBA molecule has only one adsorption configuration on Au(111) in spite of the weak van der Waals adsorption system. Based on the precisely determined adsorption geometry of DBA/Au(111), our calculation results imply that even a very small contribution of the interfacial orbital interaction at the organic-metal interface can play a decisive role in constraining the adsorption geometry even in the van der Waals adsorption system of a ?-conjugated hydrocarbon molecule on the noblest Au(111) surface. Our <span class="hlt">observations</span> provide not only deeper insight into the weak adsorption process, but also new perspectives to organic electronics using ?-conjugated hydrocarbon molecules on the Au surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15156428','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15156428"><span id="translatedtitle">Modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy for the treatment of HIV-seropositive substance users: lessons learned from a pilot study.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Macalino, Grace E; Mitty, Jennifer A; Bazerman, Lauri B; Singh, Kavita; McKenzie, Michelle; Flanigan, Timothy</p> <p>2004-06-01</p> <p>Highly active antiretroviral therapy (HAART) can dramatically decrease human immunodeficiency virus (HIV) load in plasma, increase CD4+ cell counts, and prolong life for HIV-seropositive persons. However, the need for optimal adherence has been recognized. We implemented a pilot community-based program of <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (DOT) with HAART among persons with substance use disorders and a history of failure of HAART. A near-peer outreach worker initially delivered and <span class="hlt">observed</span> once-daily HAART doses on up to 7 days per week. Many participants tapered the frequency of visits. Participants were assessed by a brief questionnaire and determination of their CD4+ cell count and plasma HIV load. Twenty-five HIV-seropositive persons were enrolled and followed-up for a mean of 6.6 months (standard deviation, 3.9 months). We found that once-daily dosing of HAART by DOT is feasible in this population; in addition to <span class="hlt">observation</span> of the majority of doses, most participants achieved virus suppression and felt favorably about the intervention. Tapering the intensity of visits with maximum flexibility was necessary to enhance the acceptability of the program to participants. PMID:15156428</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1212364','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1212364"><span id="translatedtitle">Using <span class="hlt">Direct</span> Metal Deposition to Fabricate Mold Plates for an Injection Mold Machine <span class="hlt">Allowing</span> for the Evaluation of Cost Effective Near-Sourcing Opportunities in Larger, High Volume Consumer Products</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Duty, Chad E; Groh, Bill</p> <p>2014-10-31</p> <p>ORNL collaborated with Radio Systems Corporation to investigate additive manufacturing (AM) of mold plates for plastic injection molding by <span class="hlt">direct</span> metal deposition. The team s modelling effort identified a 100% improvement in heat transfer through use of conformal cooling lines that could be built into the mold using a revolutionary design enabled by additive manufacturing. Using the newly installed laser deposition system at the ORNL Manufacturing Demonstration Facility (MDF) a stainless steel mold core was printed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23086109','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23086109"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of aluminium ions produced via pulsed laser ablation in liquid: a 'turn-on' fluorescence study.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Seulki; Ahn, Ahreum; Choi, Myong Yong</p> <p>2012-12-01</p> <p>An Al metal plate was ablated by a pulsed Nd-YAG laser to produce nano-structured Al and gamma-Al(2)O(3) in deionized water without any surfactants or catalysts. In this study, <span class="hlt">direct</span> evidence for the production of Al(3+) ions from the plasma plume is presented for the first time by characterizing the absorption and emission spectra of their [Al(salophen)](+) complex. Very interestingly, a remarkable increase in the fluorescence intensity was <span class="hlt">observed</span> when the Al(3+) ions, produced via the pulsed laser ablation, complexed with the salophen ligand. This fluorescence 'turn-on' behaviour of [Al(salophen)](+) was investigated by DFT/TD-DFT calculations. Based on these results, mechanisms for the production of aluminium and alumina nanoparticles in the pulsed laser ablation in liquid (PLAL) process are proposed. PMID:23086109</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3890906','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3890906"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Localized Spin Antiferromagnetic Transition in PdCrO2 by Angle-Resolved Photoemission Spectroscopy</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Noh, Han-Jin; Jeong, Jinwon; Chang, Bin; Jeong, Dahee; Moon, Hyun Sook; Cho, En-Jin; Ok, Jong Mok; Kim, Jun Sung; Kim, Kyoo; Min, B. I.; Lee, Han-Koo; Kim, Jae-Young; Park, Byeong-Gyu; Kim, Hyeong-Do; Lee, Seongsu</p> <p>2014-01-01</p> <p>We report the first case of the successful measurements of a localized spin antiferromagnetic transition in delafossite-type PdCrO2 by angle-resolved photoemission spectroscopy (ARPES). This demonstrates how to circumvent the shortcomings of ARPES for investigation of magnetism involved with localized spins in limited size of two-dimensional crystals or multi-layer thin films that neutron scattering can hardly study due to lack of bulk compared to surface. Also, our <span class="hlt">observations</span> give <span class="hlt">direct</span> evidence for the spin ordering pattern of Cr3+ ions in PdCrO2 suggested by neutron diffraction and quantum oscillation measurements, and provide a strong constraint that has to be satisfied by a microscopic mechanism for the unconventional anomalous Hall effect recently reported in this system. PMID:24419488</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3088622','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3088622"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of Young’s double-slit interferences in vibrationally resolved photoionization of diatomic molecules</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Canton, Sophie E.; Plésiat, Etienne; Bozek, John D.; Rude, Bruce S.; Decleva, Piero; Martín, Fernando</p> <p>2011-01-01</p> <p>Vibrationally resolved valence-shell photoionization spectra of H2, N2 and CO have been measured in the photon energy range 20–300 eV using third-generation synchrotron radiation. Young’s double-slit interferences lead to oscillations in the corresponding vibrational ratios, showing that the molecules behave as two-center electron-wave emitters and that the associated interferences leave their trace in the angle-integrated photoionization cross section. In contrast to previous work, the oscillations are <span class="hlt">directly</span> <span class="hlt">observable</span> in the experiment, thereby removing any possible ambiguity related to the introduction of external parameters or fitting functions. A straightforward extension of an original idea proposed by Cohen and Fano [Cohen HD, Fano U (1966) Phys Rev 150:30] confirms this interpretation and shows that it is also valid for diatomic heteronuclear molecules. Results of accurate theoretical calculations are in excellent agreement with the experimental findings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3544074','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3544074"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of Lomer-Cottrell Locks during strain hardening in nanocrystalline nickel by in situ TEM</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lee, Joon Hwan; Holland, Troy B.; Mukherjee, Amiya K.; Zhang, Xinghang; Wang, Haiyan</p> <p>2013-01-01</p> <p>Strain hardening capability is critical for metallic materials to achieve high ductility during plastic deformation. A majority of nanocrystalline metals, however, have inherently low work hardening capability with few exceptions. Interpretations on work hardening mechanisms in nanocrystalline metals are still controversial due to the lack of in situ experimental evidence. Here we report, by using an in situ transmission electron microscope nanoindentation tool, the <span class="hlt">direct</span> <span class="hlt">observation</span> of dynamic work hardening event in nanocrystalline nickel. During strain hardening stage, abundant Lomer-Cottrell (L-C) locks formed both within nanograins and against twin boundaries. Two major mechanisms were identified during interactions between L-C locks and twin boundaries. Quantitative nanoindentation experiments recorded show an increase of yield strength from 1.64 to 2.29?GPa during multiple loading-unloading cycles. This study provides both the evidence to explain the roots of work hardening at small length scales and the insight for future design of ductile nanocrystalline metals. PMID:23320142</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JOM...tmp..384G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JOM...tmp..384G"><span id="translatedtitle">In Situ X-Ray <span class="hlt">Observations</span> of Dendritic Fragmentation During <span class="hlt">Directional</span> Solidification of a Sn-Bi Alloy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gibbs, John W.; Tourret, Damien; Gibbs, Paul J.; Imhoff, Seth D.; Gibbs, Meghan J.; Walker, Brandon A.; Fezzaa, Kamel; Clarke, Amy J.</p> <p>2015-09-01</p> <p>Dendrite fragmentation is an important phenomenon in microstructural development during solidification. For instance, it plays a key role in initiating the columnar-to-equiaxed transition (CET). Here, we use x-ray radiography to study dendrite fragmentation rate in a Sn-39.5 wt.% Bi alloy during <span class="hlt">directional</span> solidification. Experiments were performed in which solidification was parallel and anti-parallel to gravity, leading to significantly different fragmentation rates. We quantify the distribution of fragmentation rate as a function of distance from the solidification front, time in the mushy zone, and volume fraction of solid. While the <span class="hlt">observed</span> fragmentation rate can be high, there is no evidence of a CET, illustrating that it requires more than just fragmentation to occur.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20050041672&hterms=ceres&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dceres','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20050041672&hterms=ceres&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dceres"><span id="translatedtitle">Top-of-Atmosphere <span class="hlt">Direct</span> Radiative Effect of Aerosols over Global Oceans from Merged CERES and MODIS <span class="hlt">Observations</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Loeb, N. G.; Smith, N. M.</p> <p>2004-01-01</p> <p>The <span class="hlt">direct</span> radiative effect of aerosols (DREA) is defined as the difference between radiative fluxes in the absence and presence of aerosols. In this study, the <span class="hlt">direct</span> radiative effect of aerosols is estimated for 46 months (March, 2000 to December, 2003) of merged CERES and MODIS Terra global measurements over ocean. This analysis includes the contribution from clear regions in both clear and partly cloudy CERES footprints. MODIS-CERES narrow-to-broadband regressions are developed to convert clear-sky MODIS narrowband radiances to broadband SW radiances, and CERES clear-sky Angular Distribution Models (ADMs) are used to estimate the corresponding TOA radiative fluxes needed to determine the DREA. Clear-sky MODIS pixels are identified using two independent cloud masks: (i) the NOAA-NESDIS algorithm used for inferring aerosol properties from MODIS on the CERES Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product (NOAA-SSF); and (ii) the standard algorithm used by the MODIS aerosol group to produce the MODO4 product (MODO4). Over global oceans, <span class="hlt">direct</span> radiative cooling by aerosols for clear scenes identified from MODO4 is estimated to be 5.5 W m-2, compared to 3.8 W m-2 for clear scenes from NOAA-SSF. Regionally, differences are largest in areas affected by dust aerosol, such as oceanic regions adjacent to the Saharan and Saudi Arabian deserts, and in northern Pacific Ocean regions influenced by dust transported from Asia. The net total-sky (clear and cloudy) DREA is negative (cooling) and is estimated to be -2.0 W m-2 from MOD04, and -1.6 W m-2 from NOAA-SSF. The DREA is shown to have pronounced seasonal cycles in the Northern Hemisphere and large year-to-year fluctuations near deserts. However, no systematic trend in deseasonalized anomalies of the DREA is <span class="hlt">observed</span> over the 46-month time series considered.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2938894','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2938894"><span id="translatedtitle"><span class="hlt">Directly</span> <span class="hlt">Observed</span> Patient–Physician Discussions in Palliative and End-of-Life Care: A Systematic Review of the Literature</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Reid, M. Carrington; Shengelia, Rouzi; Adelman, Ronald D.</p> <p>2010-01-01</p> <p>Abstract Objectives To review studies that used <span class="hlt">direct</span> <span class="hlt">observation</span> (i.e., videotaping or audiotaping) methods in palliative/end-of-life care communication research. Design Descriptive thematic analysis. Setting : Multinational studies were conducted in both the outpatient and inpatient setting. Measurements Extensive bibliographic searches (January 1, 1998 to July 31, 2009) of English-language literature involving physician–patient (or physician–family) interactions were conducted and augmented by reviews of reference listings. Three investigators independently abstracted key information from each article. Results Of the 20 retained articles, most enrolled young-old participants (mean age, 60 years) who were white and had a cancer diagnosis. Patient/family participation rates ranged from 68% to 89% demonstrating feasibility of this approach when studying palliative/end-of-life care communication issues. Four common themes were identified: (1) physicians focus on medical/technical and avoid emotional/quality of life issues; (2) sensitive topics are perceived by physicians to take longer to discuss and often do take longer to discuss; (3) physicians dominate discussions; and (4) patient/family satisfaction is associated with supportive physician behaviors. Conclusions This study demonstrates that <span class="hlt">direct</span> <span class="hlt">observation</span> methods can be feasibly used when studying physician–patient/physician–family communication in palliative/end-of-life care, but few investigations have utilized this approach. This article highlights areas that need improvement, including physicians' ability to address patient/family emotional issues and provide what patients and families find most satisfying (participation and support). A particular focus on older patients and patients with end-stage or late-stage chronic (noncancer) illness, the adaptation/application of existing communication measurement tools to capture palliative care communication issues, and development of corresponding outcome measures to assess impact is now needed. PMID:20491550</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/11373023','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/11373023"><span id="translatedtitle">Comparison of self-report, video <span class="hlt">observation</span> and <span class="hlt">direct</span> measurement methods for upper extremity musculoskeletal disorder physical risk factors.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Spielholz, P; Silverstein, B; Morgan, M; Checkoway, H; Kaufman, J</p> <p>2001-05-15</p> <p>The prevention of work-related musculoskeletal disorders has become a national priority in many countries. Increasingly, attempts are made to quantify those exposures that increase risk in order to set exposure limit values. This study used commonly employed field measurement methods and tools in order to perform an inter-method comparison between three primary methods of risk factor exposure assessment: self-report questionnaires, <span class="hlt">observational</span> video analysis and <span class="hlt">direct</span> measurement. Extreme posture duration, repetition, hand force (estimated from electromyography) and movement velocity were assessed for 18 subjects while performing each of three jobs processing tree seedlings. Results indicated that self-reports were the least precise assessment method, which consistently overestimated exposures for each of the measured risk factors. However, adjustment of the reports as psychophysical scales may increase agreement on a group level. Wrist flexion/extension duration and repetition were best measured by electrogoniometer. Electrogoniometric measures of wrist deviation duration and frequency were less precise than video analysis. Forearm rotation duration and repetition, grip force and velocity appeared to be best quantified by <span class="hlt">direct</span> measurement as measured by electrogoniometer and electromyography (EMG) (as root-mean-square amplitude). The results highlight the fact that it is as important to consider and report estimated measurement error in order to reduce potential exposure misclassification in epidemiologic studies. PMID:11373023</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/0908.0602.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/0908.0602.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Cosmic Strings via their Strong Gravitational Lensing Effect: II. Results from the HST/ACS Image Archive</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Morganson, Eric; Treu, Tommaso; Schrabback, Tim; Blandford, Roger D</p> <p>2009-01-01</p> <p>We have searched 4.5 square degrees of archival HST/ACS images for cosmic strings, identifying close pairs of similar, faint galaxies and selecting groups whose alignment is consistent with gravitational lensing by a long, straight string. We find no evidence for cosmic strings in five large-area HST treasury surveys (covering a total of 2.22 square degrees), or in any of 346 multi-filter guest <span class="hlt">observer</span> images (1.18 square degrees). Assuming that simulations ccurately predict the number of cosmic strings in the universe, this non-detection <span class="hlt">allows</span> us to place upper limits on the unitless Universal cosmic string tension of G mu/c^2 < 2.3 x 10^-6, and cosmic string density of Omega_s < 2.1 x 10^-5 at the 95% confidence level (marginalising over the other parameter in each case). We find four dubious cosmic string candidates in 318 single filter guest <span class="hlt">observer</span> images (1.08 square degrees), which we are unable to conclusively eliminate with existing data. The confirmation of any one of these candidates as co...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1504.03635v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1504.03635v1"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of ultrafast many-body electron dynamics in a strongly-correlated ultracold Rydberg gas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Nobuyuki Takei; Christian Sommer; Claudiu Genes; Guido Pupillo; Haruka Goto; Kuniaki Koyasu; Hisashi Chiba; Matthias Weidemüller; Kenji Ohmori</p> <p>2015-04-14</p> <p>Many-body interactions govern a variety of important quantum phenomena ranging from superconductivity and magnetism in condensed matter to solvent effects in chemistry. Understanding those interactions beyond mean field is a holy grail of modern sciences. AMO physics with advanced laser technologies has recently emerged as a new platform to study quantum many-body systems. One of its latest developments is the study of long-range interactions among ultracold particles to reveal the effects of many-body correlations. Rydberg atoms distinguish themselves by their large dipole moments and tunability of dipolar interactions. Most of ultracold Rydberg experiments have been performed with narrow-band lasers in the Rydberg blockade regime. Here we demonstrate an ultracold Rydberg gas in a complementary regime, where electronic coherence is created using a broadband picosecond laser pulse, thus circumventing the Rydberg blockade to induce strong many-body correlations. The effects of long-range Rydberg interactions have been investigated by time-domain Ramsey interferometry with attosecond precision. This approach <span class="hlt">allows</span> for the real-time <span class="hlt">observation</span> of coherent and ultrafast many-body dynamics in which the electronic coherence is modulated by the interaction-induced correlations. The modulation evolves more rapidly than expected for two-body correlations by several orders of magnitude. We have actively controlled such ultrafast many-body dynamics by tuning the principal quantum number and the population of the Rydberg state. The <span class="hlt">observed</span> Ramsey interferograms are well reproduced by a theoretical model beyond mean-field approximation, which can be relevant to other similar many-body phenomena in condensed matter physics and chemistry. Our new approach opens a new avenue to <span class="hlt">observe</span> and manipulate nonequilibrium dynamics of strongly-correlated quantum many-body systems on the ultrafast timescale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21360381','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21360381"><span id="translatedtitle">Task shifting for tuberculosis control: a qualitative study of community-based <span class="hlt">directly</span> <span class="hlt">observed</span> therapy in urban Uganda.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mafigiri, David K; McGrath, Janet W; Whalen, Christopher C</p> <p>2012-01-01</p> <p>This qualitative study of task shifting examined tuberculosis (TB) therapy under modified community-based <span class="hlt">directly</span> <span class="hlt">observed</span> treatment short-course (CB-DOTS) in Kampala, Uganda. New TB patients selected one of two strategies: home-based DOTS and clinic-based DOTS. Relevant socio-economic characteristics, treatment-seeking experiences and outcomes were assessed over eight months of follow-up. Of 107 patients recruited, 89 (83%) selected home-based DOTS. Sixty-two patients (70%) under home-based DOTS and 16 patients (89%) under clinic-based DOTS had successful outcomes following completion of tuberculosis therapy. Treatment supporters' provision of social support beyond <span class="hlt">observing</span> drug ingestion contributed to successful outcomes under both strategies. Home-based DOTS provides continuity of social support during therapy, strengthening the potential for treatment success. Conventional health facility-based DOTS can be modified in resource-limited urban Africa to offer a viable DOTS strategy that is sensitive to personal preference. Shifting the task of DOTS support away from only qualified health workers to include laypersons in the patients' social-support network may contribute to meeting World Health Organization (WHO) treatment targets. We recommend an intervention evaluating this modified DOTS strategy on a larger scale in TB high-burden, resource-poor urban settings. PMID:21360381</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3890821','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3890821"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of single stationary-phase bacteria reveals a surprisingly long period of constant protein production activity</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gefen, Orit; Fridman, Ofer; Ronin, Irine; Balaban, Nathalie Q.</p> <p>2014-01-01</p> <p>Exponentially growing bacteria are rarely found in the wild, as microorganisms tend to spend most of their lifetime at stationary phase. Despite this general prevalence of stationary-phase bacteria, they are as yet poorly characterized. Our goal was to quantitatively study this phase by <span class="hlt">direct</span> <span class="hlt">observation</span> of single bacteria as they enter into stationary phase and by monitoring their activity over several days during growth arrest. For this purpose, we devised an experimental procedure for starving single Escherichia coli bacteria in microfluidic devices and measured their activity by monitoring the production rate of fluorescent proteins. When amino acids were the sole carbon source, the production rate decreased by an order of magnitude upon entry into stationary phase. We found that, even while growth-arrested, bacteria continued to produce proteins at a surprisingly constant rate over several days. Our identification of this newly <span class="hlt">observed</span> period of constant activity in nongrowing cells, designated as constant activity stationary phase, makes possible the conduction of assays that require constant protein expression over time, and are therefore difficult to perform under exponential growth conditions. Moreover, we show that exogenous protein expression bears no fitness cost on the regrowth of the population when starvation ends. Further characterization of constant activity stationary phase—a phase where nongrowing bacteria can be quantitatively studied over several days in a reproducible manner—should contribute to a better understanding of this ubiquitous but overlooked physiological state of bacteria in nature. PMID:24344288</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApJ...746...33A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApJ...746...33A"><span id="translatedtitle"><span class="hlt">Observation</span> of Anisotropy in the Galactic Cosmic-Ray Arrival <span class="hlt">Directions</span> at 400 TeV with IceCube</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Allen, M. M.; Altmann, D.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K.-H.; Benabderrahmane, M. L.; BenZvi, S.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Bose, D.; Böser, S.; Botner, O.; Brown, A. M.; Buitink, S.; Caballero-Mora, K. S.; Carson, M.; Chirkin, D.; Christy, B.; Clevermann, F.; Cohen, S.; Colnard, C.; Cowen, D. F.; Cruz Silva, A. H.; D'Agostino, M. V.; Danninger, M.; Daughhetee, J.; Davis, J. C.; De Clercq, C.; Degner, T.; Demirörs, L.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; DeYoung, T.; Díaz-Vélez, J. C.; Dierckxsens, M.; Dreyer, J.; Dumm, J. P.; Dunkman, M.; Eisch, J.; Ellsworth, R. W.; Engdegård, O.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Fedynitch, A.; Feintzeig, J.; Feusels, T.; Filimonov, K.; Finley, C.; Fischer-Wasels, T.; Fox, B. D.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Gladstone, L.; Glüsenkamp, T.; Goldschmidt, A.; Goodman, J. A.; Góra, D.; Grant, D.; Griesel, T.; Groß, A.; Grullon, S.; Gurtner, M.; Ha, C.; Haj Ismail, A.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Heinen, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Hoffmann, B.; Homeier, A.; Hoshina, K.; Huelsnitz, W.; Hülß, J.-P.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Ishihara, A.; Jacobi, E.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kenny, P.; Kiryluk, J.; Kislat, F.; Klein, S. R.; Köhne, J.-H.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Kroll, G.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Laihem, K.; Landsman, H.; Larson, M. J.; Lauer, R.; Lünemann, J.; Madsen, J.; Marotta, A.; Maruyama, R.; Mase, K.; Matis, H. S.; Meagher, K.; Merck, M.; Mészáros, P.; Meures, T.; Miarecki, S.; Middell, E.; Milke, N.; Miller, J.; Montaruli, T.; Morse, R.; Movit, S. M.; Nahnhauer, R.; Nam, J. W.; Naumann, U.; Nygren, D. R.; Odrowski, S.; Olivas, A.; Olivo, M.; O'Murchadha, A.; Panknin, S.; Paul, L.; Pérez de los Heros, C.; Petrovic, J.; Piegsa, A.; Pieloth, D.; Porrata, R.; Posselt, J.; Price, C. C.; Price, P. B.; Przybylski, G. T.; Rawlins, K.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Richman, M.; Rodrigues, J. P.; Rothmaier, F.; Rott, C.; Ruhe, T.; Rutledge, D.; Ruzybayev, B.; Ryckbosch, D.; Sander, H.-G.; Santander, M.; Sarkar, S.; Schatto, K.; Schmidt, T.; Schönwald, A.; Schukraft, A.; Schultes, A.; Schulz, O.; Schunck, M.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strahler, E. A.; Ström, R.; Stüer, M.; Sullivan, G. W.; Swillens, Q.; Taavola, H.; Taboada, I.; Tamburro, A.; Tepe, A.; Ter-Antonyan, S.; Tilav, S.; Toale, P. A.; Toscano, S.; Tosi, D.; van Eijndhoven, N.; Vandenbroucke, J.; Van Overloop, A.; van Santen, J.; Vehring, M.; Voge, M.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Walter, M.; Weaver, Ch.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, C.; Xu, D. L.; Xu, X. W.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; Zoll, M.; IceCube Collaboration</p> <p>2012-02-01</p> <p>In this paper we report the first <span class="hlt">observation</span> in the Southern hemisphere of an energy dependence in the Galactic cosmic-ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic-ray-induced muons recorded by the partially deployed IceCube observatory between 2009 May and 2010 May. The data include a total of 33 × 109 muon events with a median angular resolution of ~3°. A sky map of the relative intensity in arrival <span class="hlt">direction</span> over the Southern celestial sky is presented for cosmic-ray median energies of 20 and 400 TeV. The same large-scale anisotropy <span class="hlt">observed</span> at median energies around 20 TeV is not present at 400 TeV. Instead, the high-energy sky map shows a different anisotropy structure including a deficit with a post-trial significance of -6.3?. This anisotropy reveals a new feature of the Galactic cosmic-ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvP...4e4008M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvP...4e4008M"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">Observation</span> of Fast Lithium-Ion Diffusion in a Superionic Conductor: Li7P3S11 Metastable Crystal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mori, Kazuhiro; Enjuji, Keigo; Murata, Shun; Shibata, Kaoru; Kawakita, Yukinobu; Yonemura, Masao; Onodera, Yohei; Fukunaga, Toshiharu</p> <p>2015-11-01</p> <p>Li7P3S11 metastable crystal attracts much attention as a solid electrolyte for all-solid-state Li-ion batteries (LIBs) because of its extremely high ionic conductivity at room temperature. Knowing the relationship between the structural framework and dynamics of Li ions will deepen the understanding of lithium-superionic conductors as solid electrolytes in LIBs. However, clarifying the dynamics of Li ions in Li7P3S11 metastable crystal is hindered by the lack of adequate techniques. In this study, we <span class="hlt">directly</span> <span class="hlt">observe</span> the fast Li-ion diffusion in Li7P3S11 metastable crystal by using state-of-the-art quasielastic neutron scattering. A signal for the self-diffusion of Li ions is clearly <span class="hlt">observed</span> at 473 K. The jump diffusion model is used to determine the self-diffusion constant D , mean residence time ?0 , and jump length ?l ? of the Li ions. We use crystal-structure analysis to successfully identify ?l ? as the average bond length lavLi - Li for the nearest-neighbor Li - Li bonds. The Li ions are located within stable regions in the conduction pathways, and the potential barrier is low between them. Consequently, we suggest that the Li ions migrate between stable regions within ?l ?=4.3 Å in Li7P3S11 metastable crystal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120015743','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120015743"><span id="translatedtitle"><span class="hlt">Observation</span> of Anisotropy in the Galactic Cosmic Ray Arrival <span class="hlt">Directions</span> at 400 TEV With IceCube</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Allen, M. M.; Altmann, D.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo, Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K. H.; Benabderrahmane, M. L.; Benzvi, S.; Berdermann, J.; Stamatikos, M.</p> <p>2011-01-01</p> <p>In this paper we report the first <span class="hlt">observation</span> in the Southern hemisphere of an energy dependence in the Galactic cosmic ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic ray induced muons recorded by the partially deployed IceCube observatory between May 2009 and May 2010. The data include a total of 33x l0(epx 9) muon events with a median angular resolution of approx 3 degrees. A sky map of the relative intensity in arrival <span class="hlt">direction</span> over the Southern celestial sky is presented for cosmic ray median energies of 20 and 400 Te V. The same large-scale anisotropy <span class="hlt">observed</span> at median energies around 20 TeV is not present at 400 TeV. Instead, the high energy skymap shows a different anisotropy structure including a deficit with a post-trial significance of -6.30 sigma. This anisotropy reveals a new feature of the Galactic cosmic ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25083648','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25083648"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of radiation-belt electron acceleration from electron-volt energies to megavolts by nonlinear whistlers.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mozer, F S; Agapitov, O; Krasnoselskikh, V; Lejosne, S; Reeves, G D; Roth, I</p> <p>2014-07-18</p> <p>The mechanisms for accelerating electrons from thermal to relativistic energies in the terrestrial magnetosphere, on the sun, and in many astrophysical environments have never been verified. We present the first <span class="hlt">direct</span> <span class="hlt">observation</span> of two processes that, in a chain, cause this acceleration in Earth's outer radiation belt. The two processes are parallel acceleration from electron-volt to kilovolt energies by parallel electric fields in time-domain structures (TDS), after which the parallel electron velocity becomes sufficiently large for Doppler-shifted upper band whistler frequencies to be in resonance with the electron gyration frequency, even though the electron energies are kilovolts and not hundreds of kilovolts. The electrons are then accelerated by the whistler perpendicular electric field to relativistic energies in several resonant interactions. TDS are packets of electric field spikes, each spike having duration of a few hundred microseconds and containing a local parallel electric field. The TDS of interest resulted from nonlinearity of the parallel electric field component in oblique whistlers and consisted of ? 0.1 msec pulses superposed on the whistler waveform with each such spike containing a net parallel potential the order of 50 V. Local magnetic field compression from remote activity provided the free energy to drive the two processes. The expected temporal correlations between the compressed magnetic field, the nonlinear whistlers with their parallel electric field spikes, the electron flux and the electron pitch angle distributions were all <span class="hlt">observed</span>. PMID:25083648</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22403369','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22403369"><span id="translatedtitle">Multiple-view spectrally resolved x-ray imaging <span class="hlt">observations</span> of polar-<span class="hlt">direct</span>-drive implosions on OMEGA</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mancini, R. C.; Johns, H. M.; Joshi, T.; Mayes, D.; Nagayama, T.; Hsu, S. C.; Baumgaertel, J. A.; Cobble, J.; Krasheninnikova, N. S.; Bradley, P. A.; Hakel, P.; Murphy, T. J.; Schmitt, M. J.; Shah, R. C.; Tregillis, I. L.; Wysocki, F. J.</p> <p>2014-12-15</p> <p>We present spatially, temporally, and spectrally resolved narrow- and broad-band x-ray images of polar-<span class="hlt">direct</span>-drive (PDD) implosions on OMEGA. These self-emission images were obtained during the deceleration phase and bang time using several multiple monochromatic x-ray imaging instruments fielded along two or three quasi-orthogonal lines-of-sight, including equatorial and polar views. The instruments recorded images based on K-shell lines from a titanium tracer located in the shell as well as continuum emission. These <span class="hlt">observations</span> constitute the first such data obtained for PDD implosions. The image data show features attributed to laser imprinting and zero-order hydrodynamics. Equatorial-view images show a “double bun” structure that is consistent with synthetic images obtained from post-processing 2D and 3D radiation-hydrodynamic simulations of the experiment. Polar-view images show a pentagonal, petal pattern that correlates with the PDD laser illumination used on OMEGA, thus revealing a 3D aspect of PDD OMEGA implosions not previously <span class="hlt">observed</span>. Differences are noted with respect to a PDD experiment performed at National Ignition Facility.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20120007458&hterms=cosmic+rays&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D%2528cosmic%2Brays%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20120007458&hterms=cosmic+rays&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D%2528cosmic%2Brays%2529"><span id="translatedtitle"><span class="hlt">Observation</span> of an Anisotropy in the Galactic Cosmic Ray Arrival <span class="hlt">Direction</span> at 400 TeV with IceCube</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Allen, M. M.; Altmann, D.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K. H.; Benabderrahmane, M. L.; BenZvi, S.; Berdermann, J.; Stamatikos, M.</p> <p>2012-01-01</p> <p>In this paper we report the first <span class="hlt">observation</span> in the Southern hemisphere of an energy dependence in the Galactic cosmic ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic ray induced muons recorded by the partially deployed IceCube observatory between May 2009 and May 2010. The data include a total of 33 x 10(exp 9) muon events with a median angular resolution of approx. 3 degrees. A sky map of the relative intensity in arrival <span class="hlt">direction</span> over the Southern celestial sky is presented for cosmic ray median energies of 20 and 400 TeV. The same large-scale anisotropy <span class="hlt">observed</span> at median energies around 20 TeV is not present at 400 TeV. Instead, the high energy skymap shows a different anisotropy structure including a deficit with a post-trial significance of -6.3 sigma. This anisotropy reveals a new feature of the Galactic cosmic ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1109.1017v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1109.1017v1"><span id="translatedtitle"><span class="hlt">Observation</span> of an Anisotropy in the Galactic Cosmic Ray arrival <span class="hlt">direction</span> at 400 TeV with IceCube</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>IceCube Collaboration; R. Abbasi; Y. Abdou; T. Abu-Zayyad; M. Ackermann; J. Adams; J. A. Aguilar; M. Ahlers; M. M. Allen; D. Altmann; K. Andeen; J. Auffenberg; X. Bai; M. Baker; S. W. Barwick; R. Bay; J. L. Bazo Alba; K. Beattie; J. J. Beatty; S. Bechet; J. K. Becker; K. -H. Becker; M. L. Benabderrahmane; S. BenZvi; J. Berdermann; P. Berghaus; D. Berley; E. Bernardini; D. Bertrand; D. Z. Besson; D. Bindig; M. Bissok; E. Blaufuss; J. Blumenthal; D. J. Boersma; C. Bohm; D. Bose; S. Böser; O. Botner; A. M. Brown; S. Buitink; K. S. Caballero-Mora; M. Carson; D. Chirkin; B. Christy; F. Clevermann; S. Cohen; C. Colnard; D. F. Cowen; A. H. Cruz Silva; M. V. D'Agostino; M. Danninger; J. Daughhetee; J. C. Davis; C. De Clercq; T. Degner; L. Demirörs; F. Descamps; P. Desiati; G. de Vries-Uiterweerd; T. DeYoung; J. C. Díaz-Vélez; M. Dierckxsens; J. Dreyer; J. P. Dumm; M. Dunkman; J. Eisch; R. W. Ellsworth; O. Engdegård; S. Euler; P. A. Evenson; O. Fadiran; A. R. Fazely; A. Fedynitch; J. Feintzeig; T. Feusels; K. Filimonov; C. Finley; T. Fischer-Wasels; B. D. Fox; A. Franckowiak; R. Franke; T. K. Gaisser; J. Gallagher; L. Gerhardt; L. Gladstone; T. Glüsenkamp; A. Goldschmidt; J. A. Goodman; D. Góra; D. Grant; T. Griesel; A. Groß; S. Grullon; M. Gurtner; C. Ha; A. Haj Ismail; A. Hallgren; F. Halzen; K. Han; K. Hanson; D. Heinen; K. Helbing; R. Hellauer; S. Hickford; G. C. Hill; K. D. Hoffman; B. Hoffmann; A. Homeier; K. Hoshina; W. Huelsnitz; J. -P. Hülß; P. O. Hulth; K. Hultqvist; S. Hussain; A. Ishihara; E. Jacobi; J. Jacobsen; G. S. Japaridze; H. Johansson; K. -H. Kampert; A. Kappes; T. Karg; A. Karle; P. Kenny; J. Kiryluk; F. Kislat; S. R. Klein; J. -H. Köhne; G. Kohnen; H. Kolanoski; L. Köpke; S. Kopper; D. J. Koskinen; M. Kowalski; T. Kowarik; M. Krasberg; G. Kroll; N. Kurahashi; T. Kuwabara; M. Labare; K. Laihem; H. Landsman; M. J. Larson; R. Lauer; J. Lünemann; J. Madsen; A. Marotta; R. Maruyama; K. Mase; H. S. Matis; K. Meagher; M. Merck; P. Mészáros; T. Meures; S. Miarecki; E. Middell; N. Milke; J. Miller; T. Montaruli; R. Morse; S. M. Movit; R. Nahnhauer; J. W. Nam; U. Naumann; D. R. Nygren; S. Odrowski; A. Olivas; M. Olivo; A. O'Murchadha; S. Panknin; L. Paul; C. Pérez de los Heros; J. Petrovic; A. Piegsa; D. Pieloth; R. Porrata; J. Posselt; C. C. Price; P. B. Price; G. T. Przybylski; K. Rawlins; P. Redl; E. Resconi; W. Rhode; M. Ribordy; M. Richman; J. P. Rodrigues; F. Rothmaier; C. Rott; T. Ruhe; D. Rutledge; B. Ruzybayev; D. Ryckbosch; H. -G. Sander; M. Santander; S. Sarkar; K. Schatto; T. Schmidt; A. Schönwald; A. Schukraft; A. Schultes; O. Schulz; M. Schunck; D. Seckel; B. Semburg; S. H. Seo; Y. Sestayo; S. Seunarine; A. Silvestri; G. M. Spiczak; C. Spiering; M. Stamatikos; T. Stanev; T. Stezelberger; R. G. Stokstad; A. Stößl; E. A. Strahler; R. Ström; M. Stüer; G. W. Sullivan; Q. Swillens; H. Taavola; I. Taboada; A. Tamburro; A. Tepe; S. Ter-Antonyan; S. Tilav; P. A. Toale; S. Toscano; D. Tosi; N. van Eijndhoven; J. Vandenbroucke; A. Van Overloop; J. van Santen; M. Vehring; M. Voge; C. Walck; T. Waldenmaier; M. Wallraff; M. Walter; Ch. Weaver; C. Wendt; S. Westerhoff; N. Whitehorn; K. Wiebe; C. H. Wiebusch; D. R. Williams; R. Wischnewski; H. Wissing; M. Wolf; T. R. Wood; K. Woschnagg; C. Xu; D. L. Xu; X. W. Xu; J. P. Yanez; G. Yodh; S. Yoshida; P. Zarzhitsky; M. Zoll</p> <p>2011-09-05</p> <p>In this paper we report the first <span class="hlt">observation</span> in the Southern hemisphere of an energy dependence in the Galactic cosmic ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic ray induced muons recorded by the partially deployed IceCube observatory between May 2009 and May 2010. The data include a total of 33$\\times 10^{9}$ muon events with a median angular resolution of $\\sim3^{\\circ}$ degrees. A sky map of the relative intensity in arrival <span class="hlt">direction</span> over the Southern celestial sky is presented for cosmic ray median energies of 20 and 400 TeV. The same large-scale anisotropy <span class="hlt">observed</span> at median energies around 20 TeV is not present at 400 TeV. Instead, the high energy skymap shows a different anisotropy structure including a deficit with a post-trial significance of -6.3$\\sigma$. This anisotropy reveals a new feature of the Galactic cosmic ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22364864','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22364864"><span id="translatedtitle"><span class="hlt">DIRECT</span> <span class="hlt">OBSERVATIONS</span> OF TETHER-CUTTING RECONNECTION DURING A MAJOR SOLAR EVENT FROM 2014 FEBRUARY 24 TO 25</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chen, Huadong; Zhang, Jun; Yang, Shuhong; Li, Ting; Cheng, Xin; Ma, Suli</p> <p>2014-12-20</p> <p>Using multi-wavelength data from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, we investigated two successive solar flares, a C5.1 confined flare and an X4.9 ejective flare with a halo coronal mass ejection, in NOAA active region 11990 from 2014 February 24 to 25. Before the confined flare onset, EUV brightening beneath the filament was detected. As the flare began, a twisted helical flux rope (FR) wrapping around the filament moved upward and then stopped, and in the meantime an obvious X-ray source below it was <span class="hlt">observed</span>. Prior to the ejective X4.9 flare, some pre-existing loop structures in the active region interacted with each other, which produced a brightening region beneath the filament. Meanwhile, a small flaring loop appeared below the interaction region and some new helical lines connecting the far ends of the loop structures were gradually formed and continually added into the former twisted FR. Then, due to the resulting imbalance between the magnetic pressure and tension, the new FR, together with the filament, erupted outward. Our <span class="hlt">observations</span> coincide well with a tether-cutting model, suggesting that the two flares probably have the same triggering mechanism, i.e., tether-cutting reconnection. To our knowledge, this is the first <span class="hlt">direct</span> <span class="hlt">observation</span> of tether-cutting reconnection occurring between pre-existing loops in an active region. In the ejective flare case, the erupting filament exhibited an ?-like kinked structure and underwent an exponential rise after a slow-rise phase, indicating that the kink instability might be also responsible for the eruption initiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://tc.dicp.ac.cn/paper/28.pdf','EPRINT'); return false;" href="http://tc.dicp.ac.cn/paper/28.pdf"><span id="translatedtitle"><span class="hlt">Direct</span> Spectroscopic <span class="hlt">Observation</span> of Fe(III)-Phenolate Complex Formed From the Reaction of Benzene With Peroxide Species on Fe/ZSM-5 At Room Temperature</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Li, Weixue</p> <p></p> <p><span class="hlt">Direct</span> Spectroscopic <span class="hlt">Observation</span> of Fe(III)-Phenolate Complex Formed From the Reaction of BenzeneVed: March 20, 2008 The reaction of benzene with the active oxygen species was studied by UV-visible diffuse as a precursor for phenol resins, fibers, dyestuffs, and medicine. The <span class="hlt">direct</span> oxidation of benzene to phenol</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title20-vol3/pdf/CFR-2011-title20-vol3-sec633-303.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title20-vol3/pdf/CFR-2011-title20-vol3-sec633-303.pdf"><span id="translatedtitle">20 CFR 633.303 - <span class="hlt">Allowable</span> costs.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-04-01</p> <p>... otherwise indicated below, <span class="hlt">direct</span> and indirect costs shall be charged in accordance with 41 CFR part 29-70... be <span class="hlt">allowable</span>, a cost must be necessary and reasonable for proper and efficient administration of the... billed as a single unit charge do not have to be allocated or prorated among the several cost...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22267705','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22267705"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of electron emission from the grain boundaries of chemical vapour deposition diamond films by tunneling atomic force microscopy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chatterjee, Vijay; Harniman, Robert; May, Paul W.; Barhai, P. K.</p> <p>2014-04-28</p> <p>The emission of electrons from diamond in vacuum occurs readily as a result of the negative electron affinity of the hydrogenated surface due to features with nanoscale dimensions, which can concentrate electric fields high enough to induce electron emission from them. Electrons can be emitted as a result of an applied electric field (field emission) with possible uses in displays or cold-cathode devices. Alternatively, electrons can be emitted simply by heating the diamond in vacuum to temperatures as low as 350?°C (thermionic emission), and this may find applications in solar energy generation or energy harvesting devices. Electron emission studies usually use doped polycrystalline diamond films deposited onto Si or metallic substrates by chemical vapor deposition, and these films have a rough, faceted morphology on the micron or nanometer scale. Electron emission is often improved by patterning the diamond surface into sharp points or needles, the idea being that the field lines concentrate at the points lowering the barrier for electron emission. However, there is little <span class="hlt">direct</span> evidence that electrons are emitted from these sharp tips. The few reports in the literature that have studied the emission sites suggested that emission came from the grain boundaries and not the protruding regions. We now present <span class="hlt">direct</span> <span class="hlt">observation</span> of the emission sites over a large area of polycrystalline diamond using tunneling atomic force microscopy. We confirm that the emission current comes mostly from the grain boundaries, which is consistent with a model for emission in which the non-diamond phase is the source of electrons with a threshold that is determined by the surrounding hydrogenated diamond surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2929153','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2929153"><span id="translatedtitle">A Qualitative Examination of the Indirect Effects of Modified <span class="hlt">Directly</span> <span class="hlt">Observed</span> Therapy on Health Behaviors Other Than Adherence</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Thomson, Domonique; Pinkston, Megan; Goggin, Kathy J.</p> <p>2008-01-01</p> <p>Abstract Modified <span class="hlt">directly</span> <span class="hlt">observed</span> therapy (mDOT), in which a portion of doses in a medication regimen are ingested under supervision, has had some demonstrated success in improving the high levels of adherence necessary to achieve maximum benefit from antiretroviral medications. Consistent with the Information-Motivation-Behavioral skills (IMB) model, mDOT's success is likely due to its <span class="hlt">direct</span> impact on patients' knowledge, motivation, and behaviors related to adherence. However, mDOT's potential impact on patients' information, motivation, and behaviors related to health activities other than adherence to antiretroviral medications has not been explored. Data from participants enrolled in Project MOTIV8, a randomized controlled trial to test the efficacy of novel behavioral adherence interventions, were analyzed to explore the potential impact of mDOT on health behaviors other than adherence. Participants were recruited from local HIV clinics from 2004–2008. Thirty-four percent of those approached, agreed to participate in the study. Data from all participants randomized to the mDOT intervention arm thus far (n?=?50, mean age 39.7 standard deviation [SD]?=?9.0, 78% male 64% African American, and 86% infected via sexual transmission) were included. Overall, participants reported a high level of satisfaction with the mDOT intervention. Qualitative data revealed that mDOT had a positive impact on participants' adherence to nonantiretroviral medications as well as their involvement and communication with health care providers. In addition, participants reported that the daily mDOT visits had indirect effects on their daily functioning, including improvements in their daily living activities (e.g., earlier awakenings, getting dressed, and cleaning their homes) and an increased level of community involvement. PMID:18627279</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyC..500...33N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyC..500...33N"><span id="translatedtitle"><span class="hlt">Direct</span> <span class="hlt">observation</span> of atomic columns in a Bi-2223 polycrystal by aberration-corrected STEM using a low accelerating voltage</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nagai, Takuro; Haruta, Mitsutaka; Kikuchi, Masashi; Zhang, Weizhu; Takeguchi, Masaki; Kimoto, Koji</p> <p>2014-05-01</p> <p>Aberration correction in scanning transmission electron microscopy (STEM) enables an atomic-scale probe size of ˜0.1 nm at a low accelerating voltage of 80 kV that avoids knock-on damage in materials including light elements such as oxygen. We used this advanced method of microscopy to <span class="hlt">directly</span> <span class="hlt">observe</span> atomic columns in a (Bi,Pb)2Sr2Ca2Cu3O10+? (Bi-2223) superconducting wire produced by a powder-in-tube method. Using the atomic-number (Z) contrast mechanism, incoherent high-angle annular dark-field (HAADF) imaging clearly showed the atomic columns. Atomic displacements toward the boundary with a maximum magnitude of ˜0.26 nm enable each atomic layer to be continuous at edge grain boundaries (EGBs). The grains tend to be terminated with deficient (Bi,Pb)-O single layers at c-axis twist boundaries (TWBs) and small-angle asymmetrical tilt boundaries (ATBs); a quantitative HAADF analysis showed that the occupancies of the (Bi,Pb) sites around these boundaries are ˜0.66 and ˜0.72, respectively. Electron energy-loss spectroscopy (EELS) mapping successfully visualized atomic columns in the half-unit cell intergrowth of (Bi,Pb)2Sr2CaCu2O8+? (Bi-2212) and (Bi,Pb)2Sr2Ca3Cu4O12+? (Bi-2234) phases. Furthermore, the HAADF analysis indicated that the occupancy of the (Bi,Pb) sites is modulated between ˜0.88 and 1.0 along the diagonal <span class="hlt">direction</span> of the primitive perovskite cell with the same period as the structural modulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16477016','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16477016"><span id="translatedtitle"><span class="hlt">Directly</span> <span class="hlt">observed</span> reversible shape changes and hemoglobin stratification during centrifugation of human and Amphiuma red blood cells.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hoffman, Joseph F; Inoué, Shinya</p> <p>2006-02-21</p> <p>This paper describes changes that occur in human and Amphiuma red blood cells <span class="hlt">observed</span> during centrifugation with a special microscope. Dilute suspensions of cells were layered, in a centrifuge chamber, above an osmotically matched dense solution, containing Nycodenz, Ficoll, or Percoll (Pharmacia) that formed a density gradient that <span class="hlt">allowed</span> the cells to slowly settle to an equilibrium position. Biconcave human red blood cells moved downward at low forces with minimum wobble. The cells oriented vertically when the force field was increased and Hb sedimented as the lower part of each cell became bulged and assumed a "bag-like" shape. The upper centripetal portion of the cell became thinner and remained biconcave. These changes occurred rapidly and were completely reversible upon lowering the centrifugal force. Bag-shaped cells, upon touching red cells in rouleau, immediately reverted to biconcave disks as they flipped onto a stack. Amphiuma red cells displayed a different type of reversible stratification and deformation at high force fields. Here the cells became stretched, with the nucleus now moving centrifugally, the Hb moving centripetally, and the bottom of the cells becoming thinner and clear. Nevertheless, the distribution of the marginal bands at the cells' rim was unchanged. We conclude that centrifugation, per se, while changing a red cell's shape and the distribution of its intracellular constituents, does so in a completely reversible manner. Centrifugation of red cells harboring altered or missing structural elements could provide information on shape determinants that are still unexplained. 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