Photoelectron Diffraction from Valence States of Oriented Molecules

NASA Astrophysics Data System (ADS)

Krüger, Peter

2018-06-01

The angular distribution of photoelectrons emitted from valence states of oriented molecules is investigated. The principles underlying the angular pattern formation are explained in terms of photoelectron wave interference, caused by initial state delocalization and final state photoelectron scattering. Computational approaches to photoelectron spectroscopy from molecules are briefly reviewed. Here a combination of molecular orbital calculations for the initial state and multiple scattering theory for the photoelectron final state is used and applied to the 3σ and 4σ orbitals of nitrogen and the highest occupied molecular orbital of pentacene. Appreciable perpendicular emission and circular dichroism in angular distributions is found, two effects that cannot be described by the popular plane wave approximation to the photoelectron final state.

Everybody Leads: A Model for Collaborative Leadership

ERIC Educational Resources Information Center

Maxfield, C. Robert; Klocko, Barbara A.

2010-01-01

This mixed-methods case study analyzes the perceptions of participants in a year-long collaborative leadership initiative conducted at a small school district situated between larger urban districts and multiple suburban districts in a midwestern state. The initiative was facilitated by the Galileo Institute for Teacher Leadership in cooperation…

What Is College and Career Readiness? A Summary of State Definitions. Bulletin, Issue 22

ERIC Educational Resources Information Center

Conforti, Peter A.

2013-01-01

This paper outlines each state's definition of college and career readiness and shows whether they associate with the Common Core State Standards Initiative (CCSSI), ACT College and Career Readiness System (ACCRS), or both. The general definition that emerges can not only facilitate interstate discussions on multiple levels, but also provide…

Chapter 4: Assessing the Air Pollution, Greenhouse Gas, Air Quality, and Health Benefits of Clean Energy Initiatives

EPA Pesticide Factsheets

Chapter 4 of Assessing the Multiple Benefits of Clean Energy helps state states understand the methods, models, opportunities, and issues associated with assessing the GHG, air pollution, air quality, and human health benefits of clean energy options.

Multiple scroll wave chimera states

NASA Astrophysics Data System (ADS)

Maistrenko, Volodymyr; Sudakov, Oleksandr; Osiv, Oleksiy; Maistrenko, Yuri

2017-06-01

We report the appearance of three-dimensional (3D) multiheaded chimera states that display cascades of self-organized spatiotemporal patterns of coexisting coherence and incoherence. We demonstrate that the number of incoherent chimera domains can grow additively under appropriate variations of the system parameters generating thereby head-adding cascades of the scroll wave chimeras. The phenomenon is derived for the Kuramoto model of N 3 identical phase oscillators placed in the unit 3D cube with periodic boundary conditions, parameters being the coupling radius r and phase lag α. To obtain the multiheaded chimeras, we perform the so-called `cloning procedure' as follows: choose a sample single-headed 3D chimera state, make appropriate scale transformation, and put some number of copies of them into the unit cube. After that, start numerical simulations with slightly perturbed initial conditions and continue them for a sufficiently long time to confirm or reject the state existence and stability. In this way it is found, that multiple scroll wave chimeras including those with incoherent rolls, Hopf links and trefoil knots admit this sort of multiheaded regeneration. On the other hand, multiple 3D chimeras without spiral rotations, like coherent and incoherent balls, tubes, crosses, and layers appear to be unstable and are destroyed rather fast even for arbitrarily small initial perturbations.

International or Global--The Expanding Universe of Librarianship

ERIC Educational Resources Information Center

Rudasill, Lynne M.

2009-01-01

This year, the United States Department of Education Title VI programs will celebrate their 50th anniversary. During the Cold War, the United States government passed the National Defense Education Act to marshal all possible resources to improve education in multiple subject areas, initiating the development of National Research Centers (NRCs) in…

Assessing the Multiple Benefits of Clean Energy Full Report

EPA Pesticide Factsheets

Guidance for state energy, environmental, and economic policy makers to identify and quantify the many benefits of clean energy to support the development and implementation of cost-effective clean energy initiatives.

Co-state initialization for the minimum-time low-thrust trajectory optimization

NASA Astrophysics Data System (ADS)

Taheri, Ehsan; Li, Nan I.; Kolmanovsky, Ilya

2017-05-01

This paper presents an approach for co-state initialization which is a critical step in solving minimum-time low-thrust trajectory optimization problems using indirect optimal control numerical methods. Indirect methods used in determining the optimal space trajectories typically result in two-point boundary-value problems and are solved by single- or multiple-shooting numerical methods. Accurate initialization of the co-state variables facilitates the numerical convergence of iterative boundary value problem solvers. In this paper, we propose a method which exploits the trajectory generated by the so-called pseudo-equinoctial and three-dimensional finite Fourier series shape-based methods to estimate the initial values of the co-states. The performance of the approach for two interplanetary rendezvous missions from Earth to Mars and from Earth to asteroid Dionysus is compared against three other approaches which, respectively, exploit random initialization of co-states, adjoint-control transformation and a standard genetic algorithm. The results indicate that by using our proposed approach the percent of the converged cases is higher for trajectories with higher number of revolutions while the computation time is lower. These features are advantageous for broad trajectory search in the preliminary phase of mission designs.

Collectivity in Small Collision Systems: An Initial-State Perspective

DOE PAGES

Schlichting, Sören; Tribedy, Prithwish

2016-01-01

Measurements of multiparticle correlations in the collisions of small systems such as p+p, p/d/ 3 He+A show striking similarity to the observations in heavy-ion collisions. A number of observables measured in the high-multiplicity events of these systems resemble features that are attributed to collectivity driven by hydrodynamics. However, alternative explanations based on initial-state dynamics are able to describe many characteristic features of these measurements. In this brief review, we highlight some of the recent developments and outstanding issues in this direction.

The multi-criteria optimization for the formation of the multiple-valued logic model of a robotic agent

NASA Astrophysics Data System (ADS)

Bykovsky, A. Yu; Sherbakov, A. A.

2016-08-01

The C-valued Allen-Givone algebra is the attractive tool for modeling of a robotic agent, but it requires the consensus method of minimization for the simplification of logic expressions. This procedure substitutes some undefined states of the function for the maximal truth value, thus extending the initially given truth table. This further creates the problem of different formal representations for the same initially given function. The multi-criteria optimization is proposed for the deliberate choice of undefined states and model formation.

Hawaii geothermal project

NASA Technical Reports Server (NTRS)

Kamins, R. M.

1974-01-01

Hawaii's Geothermal Project is investigating the occurrence of geothermal resources in the archipelago, initially on the Island of Hawaii. The state's interest in geothermal development is keen, since it is almost totally dependent on imported oil for energy. Geothermal development in Hawaii may require greater participation by the public sector than has been true in California. The initial exploration has been financed by the national, state, and county governments. Maximization of net benefits may call for multiple use of geothermal resources; the extraction of by-products and the application of treated effluents to agricultural and aquacultural uses.

"More Confident Going into College": Lessons Learned from Multiple Stakeholders in a New Blended Learning Initiative

ERIC Educational Resources Information Center

Whiteside, Aimee L.; Garrett Dikkers, Amy; Lewis, Somer

2016-01-01

This article examined a blended learning initiative in a large suburban high school in the Midwestern region of the United States. It employed a single-case exploratory design approach to learn about the experience of administrators, teachers, students, and parents. Using Zimmerman's Self-Regulated Learning (SRL) Theory as a guiding framework,…

Weak ergodicity of population evolution processes.

PubMed

Inaba, H

1989-10-01

The weak ergodic theorems of mathematical demography state that the age distribution of a closed population is asymptotically independent of the initial distribution. In this paper, we provide a new proof of the weak ergodic theorem of the multistate population model with continuous time. The main tool to attain this purpose is a theory of multiplicative processes, which was mainly developed by Garrett Birkhoff, who showed that ergodic properties generally hold for an appropriate class of multiplicative processes. First, we construct a general theory of multiplicative processes on a Banach lattice. Next, we formulate a dynamical model of a multistate population and show that its evolution operator forms a multiplicative process on the state space of the population. Subsequently, we investigate a sufficient condition that guarantees the weak ergodicity of the multiplicative process. Finally, we prove the weak and strong ergodic theorems for the multistate population and resolve the consistency problem.

Monthly mean simulation experiments with a course-mesh global atmospheric model

NASA Technical Reports Server (NTRS)

Spar, J.; Klugman, R.; Lutz, R. J.; Notario, J. J.

1978-01-01

Substitution of observed monthly mean sea-surface temperatures (SSTs) as lower boundary conditions, in place of climatological SSTs, failed to improve the model simulations. While the impact of SST anomalies on the model output is greater at sea level than at upper levels the impact on the monthly mean simulations is not beneficial at any level. Shifts of one and two days in initialization time produced small, but non-trivial, changes in the model-generated monthly mean synoptic fields. No improvements in the mean simulations resulted from the use of either time-averaged initial data or re-initialization with time-averaged early model output. The noise level of the model, as determined from a multiple initial state perturbation experiment, was found to be generally low, but with a noisier response to initial state errors in high latitudes than the tropics.

Initiation of Insensitive High Explosives Using Multiple Wave Interactions

NASA Astrophysics Data System (ADS)

Francois, Elizabeth; Burritt, Rosmary; Biss, Matt; Bowden, Patrick

2017-06-01

Insensitive High Explosives (IHEs) increase safety in many types of weapons. However, the safety comes at the cost of performance. Initiation of IHE requires large boosters and powerful detonators as well. Multipoint initiation is being utilized to exploit explosive wave interactions to create overdriven states, greatly facilitating the initiation of IHEs. This presentation will build from recent explosive experiments where the minimum spot size for single-point initiation in PBX 9502 was determined. Below this threshold, PBX 9502 could not be initiated. This was then expanded to three initiation points, which were smaller this threshold. Measurements of the velocity and pressure of the wave interactions were measured using Photon Doppler Velocimetry (PDV). Initiation was observed, and the resulting pressures at the double and triple points were found to be above the CJ state for PBX 9502. Based on these results, further tests were conducted to isolate and measure the longevity and pressure of this phenomenon using cut-back tests. All results will be presented and discussed.

Evaluation of multi-level social learning for sustainable landscapes: perspective of a development initiative in Bergslagen, Sweden.

PubMed

Axelsson, Robert; Angelstam, Per; Myhrman, Lennart; Sädbom, Stefan; Ivarsson, Milis; Elbakidze, Marine; Andersson, Kenneth; Cupa, Petr; Diry, Christian; Doyon, Frederic; Drotz, Marcus K; Hjorth, Arne; Hermansson, Jan Olof; Kullberg, Thomas; Lickers, F Henry; McTaggart, Johanna; Olsson, Anders; Pautov, Yurij; Svensson, Lennart; Törnblom, Johan

2013-03-01

To implement policies about sustainable landscapes and rural development necessitates social learning about states and trends of sustainability indicators, norms that define sustainability, and adaptive multi-level governance. We evaluate the extent to which social learning at multiple governance levels for sustainable landscapes occur in 18 local development initiatives in the network of Sustainable Bergslagen in Sweden. We mapped activities over time, and interviewed key actors in the network about social learning. While activities resulted in exchange of experiences and some local solutions, a major challenge was to secure systematic social learning and make new knowledge explicit at multiple levels. None of the development initiatives used a systematic approach to secure social learning, and sustainability assessments were not made systematically. We discuss how social learning can be improved, and how a learning network of development initiatives could be realized.

New PHOBOS results on event-by-event fluctuations

NASA Astrophysics Data System (ADS)

Alver, B.; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Chetluru, V.; Decowski, M. P.; García, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Harnarine, I.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Li, W.; Lin, W. T.; Loizides, C.; Manly, S.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Reed, C.; Remsberg, L. P.; Reuter, M.; Richardson, E.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Sedykh, I.; Skulski, W.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Szostak, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Walters, P.; Wenger, E.; Willhelm, D.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wyngaardt, S.; Wysłouch, B.

2006-04-01

We present new results from the PHOBOS experiment at RHIC on event-by-event fluctuations of particle multiplicities and angular distributions in nucleus-nucleus collisions at RHIC. Our data for Au+Au collisions at √sNN = 200 GeV show that at a level of 10-4 or less, no rare, large-amplitude fluctuations in the total multiplicity distributions or the shape of the pseudorapidity distributions are observed. We however find significant short-range multiplicity correlations in these data, that can be described as particle production in clusters. In Cu+Cu collisions, we observe large final-state azimuthal anisotropies ν2. A common scaling behavior for Cu+Cu and Au+Au for these anisotropies emerges when fluctuations in the initial state geometry are taken into account.

Core to College Evaluation: Exploring the Use of Multiple Measures for Placement into College-Level Courses. Seeking Alternatives or Improvements to the Use of a Single Standardized Test

ERIC Educational Resources Information Center

Bracco, Kathy Reeves; Dadgar, Mina; Austin, Kim; Klarin, Becca; Broek, Marie; Finkelstein, Neal; Mundry, Susan; Bugler, Dan

2014-01-01

"Core to College: Preparing Students for College Readiness and Success" is a three-year initiative. The initiative's mission is to "facilitate greater coordination between K-12 and postsecondary education systems around implementation of the Common Core State Standards (CCSS) and aligned assessments." Its aim is to foster…

Multiple hydrogen bonding in excited states of aminopyrazine in methanol solution: time-dependent density functional theory study.

PubMed

Chai, Shuo; Yu, Jie; Han, Yong-Chang; Cong, Shu-Lin

2013-11-01

Aminopyrazine (AP) and AP-methanol complexes have been theoretically studied by using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The excited-state hydrogen bonds are discussed in detail. In the ground state the intermolecular multiple hydrogen bonds can be formed between AP molecule and protic solvents. The AP monomer and hydrogen-bonded complex of AP with one methanol are photoexcited initially to the S2 state, and then transferred to the S1 state via internal conversion. However the complex of AP with two methanol molecules is directly excited to the S1 state. From the calculated electronic excited energies and simulated absorption spectra, we find that the intermolecular hydrogen bonds are strengthened in the electronic excited states. The strengthening is confirmed by the optimized excited-state geometries. The photochemical processes in the electronic excited states are significantly influenced by the excited-state hydrogen bond strengthening. Copyright © 2013 Elsevier B.V. All rights reserved.

Energy independent scaling of the ridge and final state description of high multiplicity p +p collisions at √{s }=7 and 13 TeV

NASA Astrophysics Data System (ADS)

Sarkar, Debojit

2018-02-01

An energy independent scaling of the near-side ridge yield at a given multiplicity has been observed by the ATLAS and the CMS collaborations in p +p collisions at √{s }=7 and 13 TeV. Such a striking feature of the data can be successfully explained by approaches based on initial state momentum space correlation generated due to gluon saturation. In this paper, we try to examine if such a scaling is also an inherent feature of the approaches that employ strong final state interaction in p +p collisions. We find that hydrodynamical modeling of p +p collisions using EPOS 3 shows a violation of such scaling. The current study can, therefore, provide important new insights on the origin of long-range azimuthal correlations in high multiplicity p +p collisions at the LHC energies.

From surveillance to action: early gains from the National Violent Death Reporting System.

PubMed

Campbell, R; Weis, M A; Millet, L; Powell, V; Hull-Jilly, D; Hackman, H

2006-12-01

Drawing from the experiences of individual state programs that currently participate in the National Violent Death Reporting System (NVDRS), this article reviews some of the practical benefits that may accrue from the introduction of violent death surveillance systems. As a state-based surveillance system that uses multiple data sources and relies upon multiple stakeholders, the NVDRS program has fostered an array of initiatives within and among individual state programs. State-based initiatives highlighted in this article were selected on the basis of a purposive sampling strategy intended to illustrate key aspects of program development. The NVDRS state programs are in Alaska, California, Colorado, Georgia, Kentucky, Maryland, Massachusetts, New Jersey, New Mexico, North Carolina, Oklahoma, Oregon, Rhode Island, South Carolina, Utah, Virginia, and Wisconsin. The NVDRS has helped to build alliances and collaborative efforts between key stakeholders, facilitated the recognition of violent death as a public health problem through outreach and media attention, acted as a catalyst for new projects, enhanced surveillance of special populations and utility for evaluation, and identified key circumstances that will target interventions in state prevention planning. The NVDRS has implemented data collection efforts and is beginning to produce and analyze findings. In the process of implementing the data collection system and publicizing findings, state NVDRS programs are realizing other gains that strengthen their surveillance efforts. The use of data for prevention purposes will be the ultimate indicator of program success.

Candidate R&D Thrusts for the Software Technology Initiative.

DTIC Science & Technology

1981-05-01

computer-aided design and manufacturing efforts provide examples of multiple representations and multiple manipulation modes. R&D difficulties exist in...farfetched, but the potential payoffs are enormous. References Birk, J., and R. Kelley. Research Needed to Advance the State of Knowledge in Robotics . In...and specifica- tion languages would be benefical . This R&D effort may also result in fusion with management tools with which an acquisition manager

Parallel Low-Loss Measurement of Multiple Atomic Qubits

NASA Astrophysics Data System (ADS)

Kwon, Minho; Ebert, Matthew F.; Walker, Thad G.; Saffman, M.

2017-11-01

We demonstrate low-loss measurement of the hyperfine ground state of rubidium atoms by state dependent fluorescence detection in a dipole trap array of five sites. The presence of atoms and their internal states are minimally altered by utilizing circularly polarized probe light and a strictly controlled quantization axis. We achieve mean state detection fidelity of 97% without correcting for imperfect state preparation or background losses, and 98.7% when corrected. After state detection and correction for background losses, the probability of atom loss due to the state measurement is <2 % and the initial hyperfine state is preserved with >98 % probability.

Chapter 2: Assessing the Potential Energy Impacts of Clean Energy Initiatives

EPA Pesticide Factsheets

Chapter 2 of Assessing the Multiple Benefits of Clean Energy helps state energy, environmental, and economic policy makers identify and quantify the many benefits of clean energy to support the development and implementation of cost-effective clean energ

Excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene. II. Ab initio multiple spawning simulations

NASA Astrophysics Data System (ADS)

Glover, William J.; Mori, Toshifumi; Schuurman, Michael S.; Boguslavskiy, Andrey E.; Schalk, Oliver; Stolow, Albert; Martínez, Todd J.

2018-04-01

The excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene (BD), has long been the subject of controversy due to its strong coupling, ultrafast time scales and the difficulties that theory faces in describing the relevant electronic states in a balanced fashion. Here we apply Ab Initio Multiple Spawning (AIMS) using state-averaged complete active space multistate second order perturbation theory [SA-3-CAS(4/4)-MSPT2] which describes both static and dynamic electron correlation effects, providing a balanced description of both the initially prepared bright 11Bu (ππ*) state and non-adiabatically coupled dark 21Ag state of BD. Importantly, AIMS allows for on-the-fly calculations of experimental observables. We validate our approach by directly simulating the time resolved photoelectron-photoion coincidence spectroscopy results presented in Paper I [A. E. Boguslavskiy et al., J. Chem. Phys. 148, 164302 (2018)], demonstrating excellent agreement with experiment. Our simulations reveal that the initial excitation to the 11Bu state rapidly evolves via wavepacket dynamics that follow both bright- and dark-state pathways as well as mixtures of these. In order to test the sensitivity of the AIMS results to the relative ordering of states, we considered two hypothetical scenarios biased toward either the bright 1Bu or the dark 21Ag state. In contrast with AIMS/SA-3-CAS(4/4)-MSPT2 simulations, neither of these scenarios yields favorable agreement with experiment. Thus, we conclude that the excited state non-adiabatic dynamics in BD involves both of these ultrafast pathways.

The continuous end-state comfort effect: weighted integration of multiple biases.

PubMed

Herbort, Oliver; Butz, Martin V

2012-05-01

The grasp orientation when grasping an object is frequently aligned in anticipation of the intended rotation of the object (end-state comfort effect). We analyzed grasp orientation selection in a continuous task to determine the mechanisms underlying the end-state comfort effect. Participants had to grasp a box by a circular handle-which allowed for arbitrary grasp orientations-and then had to rotate the box by various angles. Experiments 1 and 2 revealed both that the rotation's direction considerably determined grasp orientations and that end-postures varied considerably. Experiments 3 and 4 further showed that visual stimuli and initial arm postures biased grasp orientations if the intended rotation could be easily achieved. The data show that end-state comfort but also other factors determine grasp orientation selection. A simple mechanism that integrates multiple weighted biases can account for the data.

Experimental and CFD evidence of multiple solutions in a naturally ventilated building.

PubMed

Heiselberg, P; Li, Y; Andersen, A; Bjerre, M; Chen, Z

2004-02-01

This paper considers the existence of multiple solutions to natural ventilation of a simple one-zone building, driven by combined thermal and opposing wind forces. The present analysis is an extension of an earlier analytical study of natural ventilation in a fully mixed building, and includes the effect of thermal stratification. Both computational and experimental investigations were carried out in parallel with an analytical investigation. When flow is dominated by thermal buoyancy, it was found experimentally that there is thermal stratification. When the flow is wind-dominated, the room is fully mixed. Results from all three methods have shown that the hysteresis phenomena exist. Under certain conditions, two different stable steady-state solutions are found to exist by all three methods for the same set of parameters. As shown by both the computational fluid dynamics (CFD) and experimental results, one of the solutions can shift to another when there is a sufficient perturbation. These results have probably provided the strongest evidence so far for the conclusion that multiple states exist in natural ventilation of simple buildings. Different initial conditions in the CFD simulations led to different solutions, suggesting that caution must be taken when adopting the commonly used 'zero initialization'.

Airborne Intelligent Display (AID) Phase I Software Description,

DTIC Science & Technology

1983-10-24

Board Computer Characteristics 10 3.0 SOFTWARE GENERAL DESCRIPTION 13 3.1 Overview 13 3.2 System Software 14 3.2.1 System Startup 14 3.2.1.1 Initial...3 A-2 Task States A-4 A-3 Task Program Structure A-6 A-4 Task States and State Change Mechanisms A-7 A-5 Computing Return Addresses: RUNADR, SLPADR A...techniques. 2.2 Design Approach The stated objectives were met by: 1. distributing the processing load among multiple Z80 single-board computers (SBC’s). This

32 CFR 776.29 - Imputed disqualification: General rule.

Code of Federal Regulations, 2012 CFR

2012-07-01

... their federal, state, and local bar rules governing the representation of multiple or adverse clients within the same office before such representation is initiated, as such representation may expose them to... military (or Government) service may require representation of opposing sides by covered USG attorneys...

32 CFR 776.29 - Imputed disqualification: General rule.

Code of Federal Regulations, 2014 CFR

2014-07-01

... their federal, state, and local bar rules governing the representation of multiple or adverse clients within the same office before such representation is initiated, as such representation may expose them to... military (or Government) service may require representation of opposing sides by covered USG attorneys...

32 CFR 776.29 - Imputed disqualification: General rule.

Code of Federal Regulations, 2013 CFR

2013-07-01

... their federal, state, and local bar rules governing the representation of multiple or adverse clients within the same office before such representation is initiated, as such representation may expose them to... military (or Government) service may require representation of opposing sides by covered USG attorneys...

Creating Livable Communities

ERIC Educational Resources Information Center

Oberlink, Mia R.

2006-01-01

This report identifies barriers to developing livable communities and sheds light on potential methods for overcoming these barriers. It identifies and highlights multiple strategies that may be applied to the design and support of livable community principles. The identified strategies have been initiated by federal and state government agencies…

A generic multibody simulation

NASA Technical Reports Server (NTRS)

Hopping, K. A.; Kohn, W.

1986-01-01

Described is a dynamic simulation package which can be configured for orbital test scenarios involving multiple bodies. The rotational and translational state integration methods are selectable for each individual body and may be changed during a run if necessary. Characteristics of the bodies are determined by assigning components consisting of mass properties, forces, and moments, which are the outputs of user-defined environmental models. Generic model implementation is facilitated by a transformation processor which performs coordinate frame inversions. Transformations are defined in the initialization file as part of the simulation configuration. The simulation package includes an initialization processor, which consists of a command line preprocessor, a general purpose grammar, and a syntax scanner. These permit specifications of the bodies, their interrelationships, and their initial states in a format that is not dependent on a particular test scenario.

Treatment patterns in disease-modifying therapy for patients with multiple sclerosis in the United States.

PubMed

Bonafede, Machaon M; Johnson, Barbara H; Wenten, Madé; Watson, Crystal

2013-10-01

Patients with multiple sclerosis (MS) whose disease activity is inadequately controlled with a platform therapy (interferon beta or glatiramer acetate [GA]) may switch to another platform therapy or escalate therapy to natalizumab or fingolimod, which were approved in the US in 2006 and 2010, respectively. The objective of this study was to describe treatment patterns in patients with multiple sclerosis (MS) in the United States who were followed for 2 years after initiating a disease-modifying therapy (DMT). A retrospective observational cohort study was conducted to examine treatment patterns of initial DMT use (on initial therapy for 2 years with and without gaps of ≥ 60 days, medication switching, and discontinuation) among patients with MS who initiated a platform therapy (interferon-β or glatiramer acetate) or natalizumab between January 1, 2007, and September 30, 2009; the first DMT claim was the index. Eligible patients were identified in the MarketScan Commercial and Medicare Supplemental databases based on continuous enrollment for 6 months before (preindex period) and 24 months after their index date, with a diagnosis of MS and no claim for a previous DMT in the 6-month preindex period. Demographics at index and clinical characteristics during the preindex period were also analyzed. A total of 6181 MS patients were included, with 5735 (92.8%) starting on platform therapy. Natalizumab initiators were more likely to stay on index therapy (32.3% vs 16.9%, P < 0.001) and have fewer treatment gaps of ≥ 60 days (44.8% vs 55.3%, P < 0.001) compared with platform initiators. In addition, natalizumab initiators were less likely to switch treatment (13.9% vs 19.1%, P = 0.007) and took longer to switch (400.9 days vs 330.7 days, P < 0.001) compared with platform initiators. Nearly 79% of platform initiators who switched went to another platform therapy. Approximately two thirds of patients who switched to a third DMT (n = 130) switched to another platform therapy. A total of 9% of natalizumab and platform initiators discontinued DMT within the 2 years. Most MS patients initiating DMT started on platform therapy. Natalizumab initiators tended to stay on index therapy, have fewer treatment gaps, and switch less than platform initiators in the 2 years after treatment initiation. Switching between platform therapies is common despite evidence that MS patients on platform therapy may benefit from switching to natalizumab. © 2013 Elsevier HS Journals, Inc. All rights reserved.

Statistical strategy for inventorying and monitoring the ecosystem resources of the Mexican States of Jalisco and Colima at multiple scales and resolution levels

Treesearch

H. T. Schreuder; M. S. Williams; C. Aguirre-Bravo; P. L. Patterson

2003-01-01

The sampling strategy is presented for the initial phase of the natural resources pilot project in the Mexican States of Jalisco and Colima. The sampling design used is ground-based cluster sampling with poststratification based on Landsat Thematic Mapper imagery. The data collected will serve as a basis for additional data collection, mapping, and spatial modeling...

Integrating fine-scale soil data into species distribution models: preparing Soil Survey Geographic (SSURGO) data from multiple counties

Treesearch

Matthew P. Peters; Louis R. Iverson; Anantha M. Prasad; Steve N. Matthews

2013-01-01

Fine-scale soil (SSURGO) data were processed at the county level for 37 states within the eastern United States, initially for use as predictor variables in a species distribution model called DISTRIB II. Values from county polygon files converted into a continuous 30-m raster grid were aggregated to 4-km cells and integrated with other environmental and site condition...

Fatal thalamic abscess secondary to dental infection.

PubMed

Basyuni, Shadi; Sharma, Valmiki; Santhanam, Vijay; Ferro, Ashley

2015-12-17

We present the case of poor neurological recovery and subsequent death secondary to a thalamic abscess in a 53-year-old man. This patient initially presented with sudden dysarthria and left hemiparesis while driving. Neuroimaging showed a multilobular abscess involving the right thalamus with oedema extending to the basal ganglionic region and brainstem. The source of the abscess was initially unknown and it required draining multiple times while the different causes were being explored. The patient's neurological state along with intubation made for a difficult and inconclusive oral examination. It was only after neuroimaging included tooth-bearing areas that it became evident that this patient had extensive periodontal disease with multiple areas of periapical radiolucencies. The patient underwent complete dental clearance alongside repeated drainage of the abscess. Despite initial postoperative improvement, the patient never recovered from the neurological damage and died 3 weeks later. 2015 BMJ Publishing Group Ltd.

Context-specific adaptation of pursuit initiation in humans

NASA Technical Reports Server (NTRS)

Takagi, M.; Abe, H.; Hasegawa, S.; Usui, T.; Hasebe, H.; Miki, A.; Zee, D. S.; Shelhauser, M. (Principal Investigator)

2000-01-01

PURPOSE: To determine if multiple states for the initiation of pursuit, as assessed by acceleration in the "open-loop" period, can be learned and gated by context. METHODS: Four normal subjects were studied. A modified step-ramp paradigm for horizontal pursuit was used to induce adaptation. In an increasing paradigm, target velocity doubled 230 msec after onset; in a decreasing paradigm, it was halved. In the first experiment, vertical eye position (+/-5 degrees ) was used as the context cue, and the training paradigm (increasing or decreasing) changed with vertical eye position. In the second experiment, with vertical position constant, when the target was red, training was decreasing, and when green, increasing. The average eye acceleration in the first 100 msec of tracking was the index of open-loop pursuit performance. RESULTS: With vertical position as the cue, pursuit adaptation differed between up and down gaze. In some cases, the direction of adaptation was in exact accord with the training stimuli. In others, acceleration increased or decreased for both up and down gaze but always in correct relative proportion to the training stimuli. In contrast, multiple adaptive states were not induced with color as the cue. CONCLUSIONS: Multiple values for the relationship between the average eye acceleration during the initiation of pursuit and target velocity could be learned and gated by context. Vertical position was an effective contextual cue but not target color, implying that useful contextual cues must be similar to those occurring naturally, for example, orbital position with eye muscle weakness.

Comparative effectiveness and safety of thalidomide and lenalidomide in patients with multiple myeloma in the United States of America: A population-based cohort study.

PubMed

Luo, Jing; Gagne, Joshua J; Landon, Joan; Avorn, Jerry; Kesselheim, Aaron S

2017-01-01

The comparative effectiveness of thalidomide and lenalidomide in the treatment of multiple myeloma has not been established. We conducted an observational cohort study of multiple myeloma patients receiving either thalidomide or lenalidomide in routine care in the United States of America to assess their comparative survival and rates of peripheral neuropathy. Myeloma patients were identified and followed using administrative claims data from a large national health insurance provider (UnitedHealth). Patients were eligible if they initiated treatment with either lenalidomide or thalidomide between 2004 and 2013. Propensity score stratified Cox proportional hazards regression was used to estimate the hazard ratios (HR) and 95% confidence intervals (CI) for death and new-onset peripheral neuropathy (defined by International Classification of Disease, Ninth Revision codes or a new prescription intended to treat neuropathic pain). Our cohort included 1264 myeloma patients who initiated either thalidomide or lenalidomide. Among 406 new users of thalidomide, 142 (35%) developed peripheral neuropathy during a mean 499 person-days of follow-up. Among 858 new users of lenalidomide, 244 (29%) developed neuropathy during 587 person-days. Compared with thalidomide initiators, lenalidomide initiators had a reduced risk of peripheral neuropathy (HR 0.71, 95% CI: 0.56-0.92). We found no difference in rates of death (HR 1.00, 95% CI: 0.71-1.41). Our results agree with the findings of recently published trials suggesting that thalidomide and lenalidomide are equivalent with respect to survival outcomes but different with respect to neurotoxicity in clinical practice settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

ASSESSING THE CONDITION OF SOUTH CAROLINA'S ESTUARIES: A NEW APPROACH INVOLVING INTEGRATED MEASURES OF CONDITION

EPA Science Inventory

The South Carolina Estuarine and Coastal Assessment Program (SCECAP) was initiated in 1999 to assess the condition of the state's coastal habitats using multiple measures of water quality, sediment quality, and biological condition. Sampling has subsequently been expanded to incl...

Progression and prognosis in multiple system atrophy: an analysis of 230 Japanese patients.

PubMed

Watanabe, Hirohisa; Saito, Yufuko; Terao, Shinichi; Ando, Tetsuo; Kachi, Teruhiko; Mukai, Eiichiro; Aiba, Ikuko; Abe, Yuji; Tamakoshi, Akiko; Doyu, Manabu; Hirayama, Masaaki; Sobue, Gen

2002-05-01

We investigated the disease progression and survival in 230 Japanese patients with multiple system atrophy (MSA; 131 men, 99 women; 208 probable MSA, 22 definite; mean age at onset, 55.4 years). Cerebellar dysfunction (multiple system atrophy-cerebellar; MSA-C) predominated in 155 patients, and parkinsonism (multiple system atrophy-parkinsonian; MSA-P) in 75. The median time from initial symptom to combined motor and autonomic dysfunction was 2 years (range 1-10). Median intervals from onset to aid-requiring walking, confinement to a wheelchair, a bedridden state and death were 3, 5, 8 and 9 years, respectively. Patients manifesting combined motor and autonomic involvement within 3 years of onset had a significantly increased risk of not only developing advanced disease stage but also shorter survival (P < 0.01). MSA-P patients had more rapid functional deterioration than MSA-C patients (aid-requiring walking, P = 0.03; confinement to a wheelchair, P < 0.01; bedridden state, P < 0.01), but showed similar survival. Onset in older individuals showed increased risk of confinement to a wheelchair (P < 0.05), bedridden state (P = 0.03) and death (P < 0.01). Patients initially complaining of motor symptoms had accelerated risk of aid-requiring walking (P < 0.01) and confinement to a wheelchair (P < 0.01) compared with those initially complaining of autonomic symptoms, while the time until confinement to a bedridden state and survival were no worse. Gender was not associated with differences in worsening of function or survival. On MRI, a hyperintense rim at the lateral edge of the dorsolateral putamen was seen in 34.5% of cases, and a 'hot cross bun' sign in the pontine basis (PB) in 63.3%. These putaminal and pontine abnormalities became more prominent as MSA-P and MSA-C features advanced. The atrophy of the cerebellar vermis and PB showed a significant correlation particularly with the interval following the appearance of cerebellar symptoms in MSA-C (r = 0.71, P < 0.01, r = 0.76 and P < 0.01, respectively), but the relationship between atrophy and functional status was highly variable among the individuals, suggesting that other factors influenced the functional deterioration. Atrophy of the corpus callosum was seen in a subpopulation of MSA, suggesting hemispheric involvement in a subgroup of MSA patients. The present study suggested that many factors are involved in the progression of MSA but, most importantly, the interval from initial symptom to combined motor and autonomic dysfunction can predict functional deterioration and survival in MSA.

A survey of critical care nurses' practices and perceptions surrounding early intravenous antibiotic initiation during septic shock.

PubMed

Roberts, Russel J; Alhammad, Abdullah M; Crossley, Lindsay; Anketell, Eric; Wood, LeeAnn; Schumaker, Greg; Garpestad, Erik; Devlin, John W

2017-08-01

Delays in antibiotic administration after severe sepsis recognition increases mortality. While physician and pharmacy-related barriers to early antibiotic initiation have been well evaluated, those factors that affect the speed by which critical care nurses working in either the emergency department or the intensive care unit setting initiate antibiotic therapy remains poorly characterized. To evaluate the knowledge, practices and perceptions of critical care nurses regarding antibiotic initiation in patients with newly recognised septic shock. A validated survey was distributed to 122 critical care nurses at one 320-bed academic institution with a sepsis protocol advocating intravenous(IV) antibiotic initiation within 1hour of shock recognition. Among 100 (82%) critical care nurses responding, nearly all (98%) knew of the existence of the sepsis protocol. However, many critical care nurses stated they would optimise blood pressure [with either fluid (38%) or both fluid and a vasopressor (23%)] before antibiotic initiation. Communicated barriers to rapid antibiotic initiation included: excessive patient workload (74%), lack of awareness IV antibiotic(s) ordered (57%) or delivered (69%), need for administration of multiple non-antibiotic IV medications (54%) and no IV access (51%). Multiple nurse-related factors influence IV antibiotic(s) initiation speed and should be incorporated into sepsis quality improvement efforts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene. II. Ab initio multiple spawning simulations

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

Glover, William J.; Mori, Toshifumi; Schuurman, Michael S.

The excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene (BD), has long been the subject of controversy due to its strong coupling, ultrafast time scales and the difficulties that theory faces in describing the relevant electronic states in a balanced fashion. Here we apply Ab Initio Multiple Spawning (AIMS) using state-averaged complete active space multistate second order perturbation theory [SA-3-CAS(4/4)-MSPT2] which describes both static and dynamic electron correlation effects, providing a balanced description of both the initially prepared bright 1 1B u (ππ*) state and non-adiabatically coupled dark 2 1A g state of BD. Importantly, AIMS allows formore » on-the-fly calculations of experimental observables. We validate our approach by directly simulating the time resolved photoelectron-photoion coincidence spectroscopy results presented in Paper I [A. E. Boguslavskiy et al., J. Chem. Phys. 148, 164302 (2018)], demonstrating excellent agreement with experiment. Our simulations reveal that the initial excitation to the 1 1B u state rapidly evolves via wavepacket dynamics that follow both bright- and dark-state pathways as well as mixtures of these. In order to test the sensitivity of the AIMS results to the relative ordering of states, we considered two hypothetical scenarios biased toward either the bright 1B u or the dark 2 1A g state. In contrast with AIMS/SA-3-CAS(4/4)-MSPT2 simulations, neither of these scenarios yields favorable agreement with experiment. Thus, we conclude that the excited state non-adiabatic dynamics in BD involves both of these ultrafast pathways.« less

Excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene. II. Ab initio multiple spawning simulations.

PubMed

Glover, William J; Mori, Toshifumi; Schuurman, Michael S; Boguslavskiy, Andrey E; Schalk, Oliver; Stolow, Albert; Martínez, Todd J

2018-04-28

The excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene (BD), has long been the subject of controversy due to its strong coupling, ultrafast time scales and the difficulties that theory faces in describing the relevant electronic states in a balanced fashion. Here we apply Ab Initio Multiple Spawning (AIMS) using state-averaged complete active space multistate second order perturbation theory [SA-3-CAS(4/4)-MSPT2] which describes both static and dynamic electron correlation effects, providing a balanced description of both the initially prepared bright 1 1 B u (ππ*) state and non-adiabatically coupled dark 2 1 A g state of BD. Importantly, AIMS allows for on-the-fly calculations of experimental observables. We validate our approach by directly simulating the time resolved photoelectron-photoion coincidence spectroscopy results presented in Paper I [A. E. Boguslavskiy et al., J. Chem. Phys. 148, 164302 (2018)], demonstrating excellent agreement with experiment. Our simulations reveal that the initial excitation to the 1 1 B u state rapidly evolves via wavepacket dynamics that follow both bright- and dark-state pathways as well as mixtures of these. In order to test the sensitivity of the AIMS results to the relative ordering of states, we considered two hypothetical scenarios biased toward either the bright 1 B u or the dark 2 1 A g state. In contrast with AIMS/SA-3-CAS(4/4)-MSPT2 simulations, neither of these scenarios yields favorable agreement with experiment. Thus, we conclude that the excited state non-adiabatic dynamics in BD involves both of these ultrafast pathways.

Excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene. II. Ab initio multiple spawning simulations

DOE PAGES

Glover, William J.; Mori, Toshifumi; Schuurman, Michael S.; ...

2018-04-28

The excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene (BD), has long been the subject of controversy due to its strong coupling, ultrafast time scales and the difficulties that theory faces in describing the relevant electronic states in a balanced fashion. Here we apply Ab Initio Multiple Spawning (AIMS) using state-averaged complete active space multistate second order perturbation theory [SA-3-CAS(4/4)-MSPT2] which describes both static and dynamic electron correlation effects, providing a balanced description of both the initially prepared bright 1 1B u (ππ*) state and non-adiabatically coupled dark 2 1A g state of BD. Importantly, AIMS allows formore » on-the-fly calculations of experimental observables. We validate our approach by directly simulating the time resolved photoelectron-photoion coincidence spectroscopy results presented in Paper I [A. E. Boguslavskiy et al., J. Chem. Phys. 148, 164302 (2018)], demonstrating excellent agreement with experiment. Our simulations reveal that the initial excitation to the 1 1B u state rapidly evolves via wavepacket dynamics that follow both bright- and dark-state pathways as well as mixtures of these. In order to test the sensitivity of the AIMS results to the relative ordering of states, we considered two hypothetical scenarios biased toward either the bright 1B u or the dark 2 1A g state. In contrast with AIMS/SA-3-CAS(4/4)-MSPT2 simulations, neither of these scenarios yields favorable agreement with experiment. Thus, we conclude that the excited state non-adiabatic dynamics in BD involves both of these ultrafast pathways.« less

A Track Initiation Method for the Underwater Target Tracking Environment

NASA Astrophysics Data System (ADS)

Li, Dong-dong; Lin, Yang; Zhang, Yao

2018-04-01

A novel efficient track initiation method is proposed for the harsh underwater target tracking environment (heavy clutter and large measurement errors): track splitting, evaluating, pruning and merging method (TSEPM). Track initiation demands that the method should determine the existence and initial state of a target quickly and correctly. Heavy clutter and large measurement errors certainly pose additional difficulties and challenges, which deteriorate and complicate the track initiation in the harsh underwater target tracking environment. There are three primary shortcomings for the current track initiation methods to initialize a target: (a) they cannot eliminate the turbulences of clutter effectively; (b) there may be a high false alarm probability and low detection probability of a track; (c) they cannot estimate the initial state for a new confirmed track correctly. Based on the multiple hypotheses tracking principle and modified logic-based track initiation method, in order to increase the detection probability of a track, track splitting creates a large number of tracks which include the true track originated from the target. And in order to decrease the false alarm probability, based on the evaluation mechanism, track pruning and track merging are proposed to reduce the false tracks. TSEPM method can deal with the track initiation problems derived from heavy clutter and large measurement errors, determine the target's existence and estimate its initial state with the least squares method. What's more, our method is fully automatic and does not require any kind manual input for initializing and tuning any parameter. Simulation results indicate that our new method improves significantly the performance of the track initiation in the harsh underwater target tracking environment.

Effects of the Strategic Prevention Framework State Incentives Grant (SPF SIG) on state prevention infrastructure in 26 states.

PubMed

Orwin, Robert G; Stein-Seroussi, Alan; Edwards, Jessica M; Landy, Ann L; Flewelling, Robert L

2014-06-01

The Strategic Prevention Framework State Incentive Grant (SPF SIG) program is a national public health initiative sponsored by the U.S. Substance Abuse and Mental Health Services Administration's Center for Substance Abuse Prevention to prevent substance abuse and its consequences. State grantees used a data-driven planning model to allocate resources to 450 communities, which in turn launched over 2,200 intervention strategies to target prevention priorities in their respective populations. An additional goal was to build prevention capacity and infrastructure at the state and community levels. This paper addresses whether the state infrastructure goal was achieved, and what contextual and implementation factors were associated with success. The findings are consistent with claims that, overall, the SPF SIG program met its goal of increasing prevention capacity and infrastructure across multiple infrastructure domains, though the mediating effects of implementation were evident only in the evaluation/monitoring domain. The results also show that an initiative like the SPF SIG, which could easily have been compartmentalized within the states, has the potential to permeate more broadly throughout state prevention systems.

EPA'S COASTAL 2000 PROGRAM, NORTHEAST COMPONENT - AGENCIES FROM MULTIPLE STATES COLLECTING COMPARABLE ENVIRONMENTAL DATA: IT WORKS

EPA Science Inventory

Coastal 2000 is an environmental monitoring program initiated by the US Environmental Protection Agency's Office of Research and Development in 2000. The goal is to monitor selected ecological indicators in the nation's estuarine waters and produce an assessment of the health of ...

The Road to Tomorrow's Teachers: Planning, Implementing, and Evaluating a State-Based Special Education Workforce Development Initiative. Lessons Learned from the National Pilot Sites Project for Recruitment and Retention. Developing the Special Education Workforce.

ERIC Educational Resources Information Center

National Clearinghouse for Professions in Special Education, Arlington, VA.

This document describes the National Pilot Sites Project for Recruitment and Retention, an effort to recruit, prepare, and retain highly qualified diverse educators and related services personnel for children and youth with disabilities by involving multiple stakeholder groups within selected states (Alabama, Colorado, Georgia, New Jersey, Oregon,…

Attosecond transient absorption probing of electronic superpositions of bound states in neon. Detection of quantum beats

DOE PAGES

Beck, Annelise R; Bernhardt, Birgitta; Warrick, Erika R.; ...

2014-11-07

Electronic wavepackets composed of multiple bound excited states of atomic neon lying between 19.6 and 21.5 eV are launched using an isolated attosecond pulse. Individual quantum beats of the wavepacket are detected by perturbing the induced polarization of the medium with a time-delayed few-femtosecond near-infrared (NIR) pulse via coupling the individual states to multiple neighboring levels. All of the initially excited states are monitored simultaneously in the attosecond transient absorption spectrum, revealing Lorentzian to Fano lineshape spectral changes as well as quantum beats. The most prominent beating of the several that were observed was in the spin–orbit split 3d absorptionmore » features, which has a 40 femtosecond period that corresponds to the spin–orbit splitting of 0.1 eV. The few-level models and multilevel calculations confirm that the observed magnitude of oscillation depends strongly on the spectral bandwidth and tuning of the NIR pulse and on the location of possible coupling states.« less

Total teleportation of a single-photon state

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

Humble, Travis S; Bennink, Ryan S; Grice, Warren P

2008-01-01

Recent demonstrations of teleportation have transferred quantum information encoded into either polarization or field-quadrature degrees of freedom (DOFs), but an outstanding question is how to simultaneously teleport quantum information encoded into multiple DOFs. We describe how the transverse-spatial, spectral and polarization states of a single photon can be simultaneously teleported using a pair of multimode, polarization-entangled photons derived from spontaneous parametric down-conversion. Furthermore, when the initial photon pair is maximally entangled in the spatial, spectral, and polarization DOFs then the photon s full quantum state can be reliably teleported using a Bell-state measurement based on sum-frequency generation.

Wavelength dependence and multiple-induced states in photoresponses of copper phthalocyanine-doped gold nanoparticle single-electron device

NASA Astrophysics Data System (ADS)

Yamamoto, Makoto; Ueda, Rieko; Terui, Toshifumi; Imazu, Keisuke; Tamada, Kaoru; Sakano, Takeshi; Matsuda, Kenji; Ishii, Hisao; Noguchi, Yutaka

2014-01-01

We have proposed a gold nanoparticle (GNP)-based single-electron transistor (SET) doped with a dye molecule, where the molecule works as a photoresponsive floating gate. Here, we examined the source-drain current (I_{\\text{SD}}) at a constant drain voltage under light irradiation with various wavelengths ranging from 400 to 700 nm. Current change was enhanced at the wavelengths of 600 and 700 nm, corresponding to the optical absorption band of the doped molecule (copper phthalocyanine: CuPc). Moreover, several peaks appear in the histograms of I_{\\text{SD}} during light irradiation, indicating that multiple discrete states were induced in the device. The results suggest that the current change was initiated by the light absorption of CuPc and multiple CuPc molecules near the GNP working as a floating gate. Molecular doping can activate advanced device functions in GNP-based SETs.

Replica exchange enveloping distribution sampling (RE-EDS): A robust method to estimate multiple free-energy differences from a single simulation.

PubMed

Sidler, Dominik; Schwaninger, Arthur; Riniker, Sereina

2016-10-21

In molecular dynamics (MD) simulations, free-energy differences are often calculated using free energy perturbation or thermodynamic integration (TI) methods. However, both techniques are only suited to calculate free-energy differences between two end states. Enveloping distribution sampling (EDS) presents an attractive alternative that allows to calculate multiple free-energy differences in a single simulation. In EDS, a reference state is simulated which "envelopes" the end states. The challenge of this methodology is the determination of optimal reference-state parameters to ensure equal sampling of all end states. Currently, the automatic determination of the reference-state parameters for multiple end states is an unsolved issue that limits the application of the methodology. To resolve this, we have generalised the replica-exchange EDS (RE-EDS) approach, introduced by Lee et al. [J. Chem. Theory Comput. 10, 2738 (2014)] for constant-pH MD simulations. By exchanging configurations between replicas with different reference-state parameters, the complexity of the parameter-choice problem can be substantially reduced. A new robust scheme to estimate the reference-state parameters from a short initial RE-EDS simulation with default parameters was developed, which allowed the calculation of 36 free-energy differences between nine small-molecule inhibitors of phenylethanolamine N-methyltransferase from a single simulation. The resulting free-energy differences were in excellent agreement with values obtained previously by TI and two-state EDS simulations.

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

Macaluso, D. A.; Bogolub, K.; Johnson, A.

Absolute single photoionization cross-section measurements of Rb 2+ ions were performed at the Advanced Light Source at Lawrence Berkeley National Laboratory using synchrotron radiation and the photo-ion, merged-beams technique. Measurements were made at a photon energy resolution of 13.5 2.5 meV from 37.31 to 44.08 eV spanning the 2 P ground state and 2 P metastable state ionization thresholds. Multiple autoionizing resonance series arising from each initial state are identified using quantum defect theory. The measurements are compared to Breit-Pauli R-matrix calculations with excellent agreement between theory and experiment.

Entanglement Distillation from Greenberger-Horne-Zeilinger Shares

NASA Astrophysics Data System (ADS)

Vrana, Péter; Christandl, Matthias

2017-06-01

We study the problem of converting a product of Greenberger-Horne-Zeilinger (GHZ) states shared by subsets of several parties in an arbitrary way into GHZ states shared by every party. Such a state can be described by a hypergraph on the parties as vertices and with each hyperedge corresponding to a GHZ state shared among the parties incident with it. Our result is that if SLOCC transformations are allowed, then the best asymptotic rate is the minimum of bipartite log-ranks of the initial state, which in turn equals the minimum cut of the hypergraph. This generalizes a result by Strassen on the asymptotic subrank of the matrix multiplication tensor.

Enhanced disease characterization through multi network functional normalization in fMRI.

PubMed

Çetin, Mustafa S; Khullar, Siddharth; Damaraju, Eswar; Michael, Andrew M; Baum, Stefi A; Calhoun, Vince D

2015-01-01

Conventionally, structural topology is used for spatial normalization during the pre-processing of fMRI. The co-existence of multiple intrinsic networks which can be detected in the resting brain are well-studied. Also, these networks exhibit temporal and spatial modulation during cognitive task vs. rest which shows the existence of common spatial excitation patterns between these identified networks. Previous work (Khullar et al., 2011) has shown that structural and functional data may not have direct one-to-one correspondence and functional activation patterns in a well-defined structural region can vary across subjects even for a well-defined functional task. The results of this study and the existence of the neural activity patterns in multiple networks motivates us to investigate multiple resting-state networks as a single fusion template for functional normalization for multi groups of subjects. We extend the previous approach (Khullar et al., 2011) by co-registering multi group of subjects (healthy control and schizophrenia patients) and by utilizing multiple resting-state networks (instead of just one) as a single fusion template for functional normalization. In this paper we describe the initial steps toward using multiple resting-state networks as a single fusion template for functional normalization. A simple wavelet-based image fusion approach is presented in order to evaluate the feasibility of combining multiple functional networks. Our results showed improvements in both the significance of group statistics (healthy control and schizophrenia patients) and the spatial extent of activation when a multiple resting-state network applied as a single fusion template for functional normalization after the conventional structural normalization. Also, our results provided evidence that the improvement in significance of group statistics lead to better accuracy results for classification of healthy controls and schizophrenia patients.

Multiple electron processes of He and Ne by proton impact

NASA Astrophysics Data System (ADS)

Terekhin, Pavel Nikolaevich; Montenegro, Pablo; Quinto, Michele; Monti, Juan; Fojon, Omar; Rivarola, Roberto

2016-05-01

A detailed investigation of multiple electron processes (single and multiple ionization, single capture, transfer-ionization) of He and Ne is presented for proton impact at intermediate and high collision energies. Exclusive absolute cross sections for these processes have been obtained by calculation of transition probabilities in the independent electron and independent event models as a function of impact parameter in the framework of the continuum distorted wave-eikonal initial state theory. A binomial analysis is employed to calculate exclusive probabilities. The comparison with available theoretical and experimental results shows that exclusive probabilities are needed for a reliable description of the experimental data. The developed approach can be used for obtaining the input database for modeling multiple electron processes of charged particles passing through the matter.

Shock-adiabatic to quasi-isentropic compression of warm dense helium up to 150 GPa

NASA Astrophysics Data System (ADS)

Zheng, J.; Chen, Q. F.; Gu, Y. J.; Li, J. T.; Li, Z. G.; Li, C. J.; Chen, Z. Y.

2017-06-01

Multiple reverberation compression can achieve higher pressure, higher temperature, but lower entropy. It is available to provide an important validation for the elaborate and wider planetary models and simulate the inertial confinement fusion capsule implosion process. In the work, we have developed the thermodynamic and optical properties of helium from shock-adiabatic to quasi-isentropic compression by means of a multiple reverberation technique. By this technique, the initial dense gaseous helium was compressed to high pressure and high temperature and entered the warm dense matter (WDM) region. The experimental equation of state (EOS) of WDM helium in the pressure-density-temperature (P-ρ -T) range of 1 -150 GPa , 0.1 -1.1 g c m-3 , and 4600-24 000 K were measured. The optical radiations emanating from the WDM helium were recorded, and the particle velocity profiles detecting from the sample/window interface were obtained successfully up to 10 times compression. The optical radiation results imply that dense He has become rather opaque after the 2nd compression with a density of about 0.3 g c m-3 and a temperature of about 1 eV. The opaque states of helium under multiple compression were analyzed by the particle velocity measurements. The multiple compression technique could efficiently enhanced the density and the compressibility, and our multiple compression ratios (ηi=ρi/ρ0,i =1 -10 ) of helium are greatly improved from 3.5 to 43 based on initial precompressed density (ρ0) . For the relative compression ratio (ηi'=ρi/ρi -1) , it increases with pressure in the lower density regime and reversely decreases in the higher density regime, and a turning point occurs at the 3rd and 4th compression states under the different loading conditions. This nonmonotonic evolution of the compression is controlled by two factors, where the excitation of internal degrees of freedom results in the increasing compressibility and the repulsive interactions between the particles results in the decreasing compressibility at the onset of electron excitation and ionization. In the P-ρ -T contour with the experiments and the calculations, our multiple compression states from insulating to semiconducting fluid (from transparent to opaque fluid) are illustrated. Our results give an elaborate validation of EOS models and have applications for planetary and stellar opaque atmospheres.

Individual and Contextual Factors Related to Secondary Special Education Teachers' Reading Instructional Practices

ERIC Educational Resources Information Center

Leko, Melinda M.; Chiu, Ming Ming; Roberts, Carly A.

2018-01-01

This article reports findings from an initial investigation of the impact multiple individual and contextual factors have on secondary special educators' reading instructional practices. Data from 577 special educators from 221 school districts in a large Midwestern state were collected via an online and paper survey and analyzed using…

Blurring the Boundaries: Reflecting on PDS Roles and Responsibilities through Multiple Lenses

ERIC Educational Resources Information Center

Larson, Lotta C.; Lickteig, Amanda D.; Sherbert, Vicki S.; Nauerth, Deborah A.

2014-01-01

It is well documented that successful Professional Development School (PDS) initiatives are contingent on trusting relationships between the university and school districts. Over the past 25 years, continual efforts have been made by the Kansas State University (KSU) PDS to minimize notions of status while maintaining mutually beneficial goals and…

Service-Learning from a Distance: Partnering Multiple Universities and Local Governments in a Large Scale Initiative

ERIC Educational Resources Information Center

Poindexter, Sandra; Arnold, Pamela; Osterhout, Christopher

2009-01-01

Service-learning can be academically effective even when the distances between students and client organizations prevent face-to-face interchanges and site visits. Working with the State of Michigan and Michigan Townships Association, Michigan students from five universities learned about local government while helping Michigan townships develop…

Initial implementation of The National Map

USGS Publications Warehouse

Roth, K.

2003-01-01

The development of The National Map is "national" in the broadest sense of the word. Although the U.S. Geological Survey is taking the lead, local governments, states, and regions are active and essential partners in the process, contributing, for example, data updates, problem-solving data integration, and map development from multiple data layers.

Challenges of Literacy Coaching in High School

ERIC Educational Resources Information Center

Gross, Patricia A.

2012-01-01

This qualitative case study examined a state-run, foundation-funded initiative to introduce literacy coaching in a medium-sized urban high school district over a period of two years. Data analyses revealed the complex development and multiple understandings of the process of literacy coaching on the secondary level. The role of the coaches…

Relationships between Observations of Elementary Mathematics Instruction and Student Achievement: Exploring Variability across Districts

ERIC Educational Resources Information Center

Lynch, Kathleen; Chin, Mark; Blazar, David

2017-01-01

Much debate surrounding teacher quality has focused on students' standardized test scores, but recent federal and state initiatives have emphasized the use of multiple measures to evaluate teacher quality, including classroom observations. In this study, we explore differences across school districts in the relationship between student achievement…

Community Colleges: Multiple Missions, Diverse Student Bodies, and a Range of Policy Solutions

ERIC Educational Resources Information Center

Baime, David; Baum, Sandy

2016-01-01

The national commitment to increasing postsecondary educational attainment, combined with growing economic anxiety, has made community colleges the focus of many federal and state policy initiatives. There is good reason for this: by virtue of their nature and reach, community colleges--public institutions of higher education that predominantly…

Practical management of anticoagulation in patients with atrial fibrillation.

PubMed

Kovacs, Richard J; Flaker, Greg C; Saxonhouse, Sherry J; Doherty, John U; Birtcher, Kim K; Cuker, Adam; Davidson, Bruce L; Giugliano, Robert P; Granger, Christopher B; Jaffer, Amir K; Mehta, Bella H; Nutescu, Edith; Williams, Kim A

2015-04-07

Anticoagulation for atrial fibrillation has become more complex due to the introduction of new anticoagulant agents, the number and kinds of patients requiring therapy, and the interactions of those patients in the matrix of care. The management of anticoagulation has become a "team sport" involving multiple specialties in multiple sites of care. The American College of Cardiology, through the College's Anticoagulation Initiative, convened a roundtable of experts from multiple specialties to discuss topics important to the management of patients requiring anticoagulation and to make expert recommendations on issues such as the initiation and interruption of anticoagulation, quality of anticoagulation care, management of major and minor bleeding, and treatment of special populations. The attendees continued to work toward consensus on these topics, and present the key findings of this roundtable in a state-of- the-art review focusing on the practical aspects of anticoagulation care for the patient with atrial fibrillation. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Comparison study for multiple ionization of carbonyl sulfide by linearly and circularly polarized intense femtosecond laser fields using Coulomb explosion imaging

NASA Astrophysics Data System (ADS)

Ma, Pan; Wang, Chuncheng; Luo, Sizuo; Yu, Xitao; Li, Xiaokai; Wang, Zhenzhen; Hu, Wenhui; Yu, Jiaqi; Yang, Yizhang; Tian, Xu; Cui, Zhonghua; Ding, Dajun

2018-05-01

We studied the relative yields and dissociation dynamics for two- and three-body Coulomb explosion (CE) channels from highly charged carbonyl sulfide molecules in intense laser fields using the CE imaging technique. The electron recollision contributions are evaluated by comparing the relative yields for the multiple ionization process in linearly polarized and circularly polarized (LP and CP) laser fields. The nonsequential multiple ionization is only confirmed for the charge states of 2 to 4 because the energy for further ionization from the inner orbital is much larger than the maximum recollision energy, 3.2U p . The novel deviations of kinetic energy releases distributions between LP and CP pulses are observed for the charge states higher than 4. It can be attributed to the stronger molecular bending in highly charged states before three-body CE with CP light, in which the bending wave packet is initialed by the triple or quartic ionization and spread along their potential curves. Compared to LP light, CP light ionizes a larger fraction of bending molecules in the polarization plane.

The development of tool use: Planning for end-state comfort

PubMed Central

Comalli, David M.; Keen, Rachel; Abraham, Evelyn S.; Foo, Victoria J.; Lee, Mei-Hua; Adolph, Karen E.

2016-01-01

Some grips on the handle of a tool can be planned based on information directly available in the scene. Other grips, however, must be planned based on the final position of the hand. “End-state comfort” grips require an awkward or uncomfortable initial grip so as to later implement the action comfortably and efficiently. From a cognitive perspective, planning for end-state comfort requires a consistent representation of the entire action sequence, including the latter part, which is not based on information directly available in the scene. Many investigators have found that young children fail to demonstrate planning for end-state comfort and that adult-like performance does not appear until about 12 years of age. In two experiments, we used a hammering task that engaged children in a goal-directed action with multiple steps. We assessed end-state-comfort planning in novel ways by measuring children’s hand choice, grip choice, and tool implementation over multiple trials. The hammering task also uniquely allowed us to assess the efficiency of implementation. We replicated the previous developmental trend in 4-, 8-, and 12-year-old children with our novel task. Most important, our data revealed that 4-year-olds are in a transitional stage with several competing strategies exhibited during a single session. Preschoolers changed their grip within trials and across trials, indicating awareness of errors and a willingness to sacrifice speed for more efficient implementation. The end-state-comfort grip initially competes as one grip type among many, but gradually displaces all others. Children’s sensitivity to and drive for efficiency may motivate this change. PMID:27786531

An analytical derivation of MC-SCF vibrational wave functions for the quantum dynamical simulation of multiple proton transfer reactions: Initial application to protonated water chains

NASA Astrophysics Data System (ADS)

Drukker, Karen; Hammes-Schiffer, Sharon

1997-07-01

This paper presents an analytical derivation of a multiconfigurational self-consistent-field (MC-SCF) solution of the time-independent Schrödinger equation for nuclear motion (i.e. vibrational modes). This variational MC-SCF method is designed for the mixed quantum/classical molecular dynamics simulation of multiple proton transfer reactions, where the transferring protons are treated quantum mechanically while the remaining degrees of freedom are treated classically. This paper presents a proof that the Hellmann-Feynman forces on the classical degrees of freedom are identical to the exact forces (i.e. the Pulay corrections vanish) when this MC-SCF method is used with an appropriate choice of basis functions. This new MC-SCF method is applied to multiple proton transfer in a protonated chain of three hydrogen-bonded water molecules. The ground state and the first three excited state energies and the ground state forces agree well with full configuration interaction calculations. Sample trajectories are obtained using adiabatic molecular dynamics methods, and nonadiabatic effects are found to be insignificant for these sample trajectories. The accuracy of the excited states will enable this MC-SCF method to be used in conjunction with nonadiabatic molecular dynamics methods. This application differs from previous work in that it is a real-time quantum dynamical nonequilibrium simulation of multiple proton transfer in a chain of water molecules.

Quantum caustics in resonance-fluorescence trajectories

NASA Astrophysics Data System (ADS)

Naghiloo, M.; Tan, D.; Harrington, P. M.; Lewalle, P.; Jordan, A. N.; Murch, K. W.

2017-11-01

We employ phase-sensitive amplification to perform homodyne detection of the resonance fluorescence from a driven superconducting artificial atom. Entanglement between the emitter and its fluorescence allows us to track the individual quantum state trajectories of the emitter conditioned on the outcomes of the field measurements. We analyze the ensemble properties of these trajectories by considering trajectories that connect specific initial and final states. By applying the stochastic path-integral formalism, we calculate equations of motion for the most-likely path between two quantum states and compare these predicted paths to experimental data. Drawing on the mathematical similarity between the action formalism of the most-likely quantum paths and ray optics, we study the emergence of caustics in quantum trajectories: places where multiple extrema in the stochastic action occur. We observe such multiple most-likely paths in experimental data and find these paths to be in reasonable quantitative agreement with theoretical calculations.

Resonance fluorescence trajectories in superconducting qubit

NASA Astrophysics Data System (ADS)

Naghiloo, Mahdi; Tan, Dian; Harrington, Patrick; Lewalle, Philippe; Jordan, Andrew; Murch, Kater

We employ phase-sensitive amplification to perform homodyne detection of the resonance fluorescence from a driven superconducting artificial atom. Entanglement between the emitter and its fluorescence allows us to track the individual quantum state trajectories of the emitter. We analyze the ensemble properties of these trajectories by considering paths that connect specific initial and final states. By applying a stochastic path integral formalism, we calculate equations of motion for the most likely path between two quantum states and compare these predicted paths to experimental data. Drawing on the mathematical similarity between the action formalism of the most likely quantum paths and ray optics, we study the emergence of caustics in quantum trajectories-situations where multiple extrema in the stochastic action occur. We observe such multiple most likely paths in experimental data and find these paths to be in reasonable quantitative agreement with theoretical calculations. Supported by the John Templeton Foundation.

Ab Initio Multiple Spawning Photochemical Dynamics of DMABN Using GPUs

DOE PAGES

Curchod, Basile F. E.; Sisto, Aaron; Martinez, Todd J.

2016-12-15

The ultrafast decay dynamics of 4-( N,N-dimethylamino)benzonitrile (DMABN) following photoexcitation was studied with the ab initio multiple spawning (AIMS) method, combined with GPU-accelerated linear-response time-dependent density functional theory (LR-TDDFT). We validate the LR-TDDFT method for this case and then present a detailed analysis of the first ≈200 fs of DMABN excited-state dynamics. Almost complete nonadiabatic population transfer from S 2 (the initially populated bright state) to S 1 takes place in less than 50 fs, without significant torsion of the dimethylamino (DMA) group. Significant torsion of the DMA group is only observed after the nuclear wavepacket reaches S 1 andmore » acquires locally excited electronic character. Here, our results show that torsion of the DMA group is not prerequisite for nonadiabatic transitions in DMABN, although such motion is indeed relevant on the lowest excited state (S 1).« less

[Association of Kaposi sarcoma--multiple myeloma. A new case].

PubMed

Cohen, J D; Thomas, E; Garnier, N; Hellier, I; Durand, L; Guilhou, J J; Baldet, P; Blotman, F

2000-11-01

Kaposi's disease is an angiogenic multifocal cancer process that has several forms, namely Mediterranean, African, HIV-associated, and secondary to a preexisting immunodepressive state (hematological disorder, corticosteroid therapy, immunodepressive treatment). Whatever its form, Kaposi's sarcoma is probably associated with a chronic viral human herpes type 8 infection (HHV8). This virus has been implicated in the pathogenesis of multiple myeloma (17 cases recorded to date). In the present study, a further case of Kaposi's sarcoma associated with multiple myeloma has been reported. However, Epstein-Barr virus, cytomegalovirus, hepatitis B and C, HIV and HHV8 serologies were negative. Radiotherapy on the lower limbs was initiated. It is concluded that HHV8 does not appear to play a pathogenic role in cases of multiple myeloma, given the rarity of the association between Kaposi's sarcoma/multiple myeloma/HHV8.

Streptococcus anginosus endocarditis and multiple liver abscesses in a splenectomised patient.

PubMed

Finn, Talya; Schattner, Ami; Dubin, Ina; Cohen, Regev

2018-04-27

An unusual case of infective endocarditis and concurrent multiple liver abscesses both caused by Streptococcus anginosus in a splenectomised patient is reported. The microorganism is a very rare cause of endocarditis and its presentation with multiple liver abscesses is highly unusual. It was initially misdiagnosed as Streptococcus sanguinis and issues relating to the different clinical presentations of S. anginosus including the rare cases of endocarditis, the role of the patient's splenectomy and problems that may contribute to its potential laboratory misidentifications are discussed. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The Nanomaterial Data Curation Initiative: A collaborative approach to assessing, evaluating, and advancing the state of the field

PubMed Central

Powers, Christina M; Hoover, Mark D; Harper, Stacey L

2015-01-01

Summary The Nanomaterial Data Curation Initiative (NDCI), a project of the National Cancer Informatics Program Nanotechnology Working Group (NCIP NanoWG), explores the critical aspect of data curation within the development of informatics approaches to understanding nanomaterial behavior. Data repositories and tools for integrating and interrogating complex nanomaterial datasets are gaining widespread interest, with multiple projects now appearing in the US and the EU. Even in these early stages of development, a single common aspect shared across all nanoinformatics resources is that data must be curated into them. Through exploration of sub-topics related to all activities necessary to enable, execute, and improve the curation process, the NDCI will provide a substantive analysis of nanomaterial data curation itself, as well as a platform for multiple other important discussions to advance the field of nanoinformatics. This article outlines the NDCI project and lays the foundation for a series of papers on nanomaterial data curation. The NDCI purpose is to: 1) present and evaluate the current state of nanomaterial data curation across the field on multiple specific data curation topics, 2) propose ways to leverage and advance progress for both individual efforts and the nanomaterial data community as a whole, and 3) provide opportunities for similar publication series on the details of the interactive needs and workflows of data customers, data creators, and data analysts. Initial responses from stakeholder liaisons throughout the nanoinformatics community reveal a shared view that it will be critical to focus on integration of datasets with specific orientation toward the purposes for which the individual resources were created, as well as the purpose for integrating multiple resources. Early acknowledgement and undertaking of complex topics such as uncertainty, reproducibility, and interoperability is proposed as an important path to addressing key challenges within the nanomaterial community, such as reducing collateral negative impacts and decreasing the time from development to market for this new class of technologies. PMID:26425427

Reconstruction after complex facial trauma: achieving optimal outcome through multiple contemporary surgeries.

PubMed

Jaiswal, Rohit; Pu, Lee L Q

2013-04-01

Major facial trauma injuries often require complex repair. Traditionally, the reconstruction of such injuries has primarily utilized only free tissue transfer. However, the advent of newer, contemporary procedures may lead to potential reconstructive improvement through the use of complementary procedures after free flap reconstruction. An 18-year-old male patient suffered a major left facial degloving injury resulting in soft-tissue defect with exposed zygoma, and parietal bone. Multiple operations were undertaken in a staged manner for reconstruction. A state-of-the-art free anterolateral thigh (ALT) perforator flap and Medpor implant reconstruction of the midface were initially performed, followed by flap debulking, lateral canthopexy, midface lift with redo canthopexy, scalp tissue expansion for hairline reconstruction, and epidermal skin grafting for optimal skin color matching. Over a follow-up period of 2 years, a good and impressive reconstructive result was achieved through the use of multiple contemporary reconstructive procedures following an excellent free ALT flap reconstruction. Multiple staged reconstructions are essential in producing an optimal outcome in this complex facial injury that would likely not have been produced through a 1-stage traditional free flap reconstruction. Utilizing multiple, sequential contemporary surgeries may substantially improve outcome through the enhancement and refinement of results based on possibly the best initial soft-tissue reconstruction.

Exciton multiplication from first principles.

PubMed

Jaeger, Heather M; Hyeon-Deuk, Kim; Prezhdo, Oleg V

2013-06-18

Third-generation photovolatics require demanding cost and power conversion efficiency standards, which may be achieved through efficient exciton multiplication. Therefore, generating more than one electron-hole pair from the absorption of a single photon has vast ramifications on solar power conversion technology. Unlike their bulk counterparts, irradiated semiconductor quantum dots exhibit efficient exciton multiplication, due to confinement-enhanced Coulomb interactions and slower nonradiative losses. The exact characterization of the complicated photoexcited processes within quantum-dot photovoltaics is a work in progress. In this Account, we focus on the photophysics of nanocrystals and investigate three constituent processes of exciton multiplication, including photoexcitation, phonon-induced dephasing, and impact ionization. We quantify the role of each process in exciton multiplication through ab initio computation and analysis of many-electron wave functions. The probability of observing a multiple exciton in a photoexcited state is proportional to the magnitude of electron correlation, where correlated electrons can be simultaneously promoted across the band gap. Energies of multiple excitons are determined directly from the excited state wave functions, defining the threshold for multiple exciton generation. This threshold is strongly perturbed in the presence of surface defects, dopants, and ionization. Within a few femtoseconds following photoexcitation, the quantum state loses coherence through interactions with the vibrating atomic lattice. The phase relationship between single excitons and multiple excitons dissipates first, followed by multiple exciton fission. Single excitons are coupled to multiple excitons through Coulomb and electron-phonon interactions, and as a consequence, single excitons convert to multiple excitons and vice versa. Here, exciton multiplication depends on the initial energy and coupling magnitude and competes with electron-phonon energy relaxation. Multiple excitons are generated through impact ionization within picoseconds. The basis of exciton multiplication in quantum dots is the collective result of photoexcitation, dephasing, and nonadiabatic evolution. Each process is characterized by a distinct time-scale, and the overall multiple exciton generation dynamics is complete by about 10 ps. Without relying on semiempirical parameters, we computed quantum mechanical probabilities of multiple excitons for small model systems. Because exciton correlations and coherences are microscopic, quantum properties, results for small model systems can be extrapolated to larger, realistic quantum dots.

Professional Practice, Student Surveys, and Value-Added: Multiple Measures of Teacher Effectiveness in the Pittsburgh Public Schools. REL 2014-024

ERIC Educational Resources Information Center

Chaplin, Duncan; Gill, Brian; Thompkins, Allison; Miller, Hannah

2014-01-01

Responding to federal and state prompting, school districts across the country are implementing new teacher evaluation systems that aim to increase the rigor of evaluation ratings, better differentiate effective teaching, and support personnel and staff development initiatives that promote teacher effectiveness and ultimately improve student…

Integration of Nuclear- and Extranuclear-Initiated Estrogen Receptor Signaling in Breast Cancer Cells

ERIC Educational Resources Information Center

Madak Erdogan, Zeynep

2009-01-01

Estrogenic hormones exert their effects through binding to Estrogen Receptors (ERs), which work in concert with coregulators and extranuclear signaling pathways to control gene expression in normal as well as cancerous states, including breast tumors. In this thesis, we have used multiple genome-wide analysis tools to elucidate various ways that…

Early generation selection at multiple locations may identify potato parents that produce more widely adapted progency

USDA-ARS?s Scientific Manuscript database

Potato production in the eastern U.S. occurs over a wide range of environments from Maine to Florida; many of these states do not have a breeding program. Initial selections are usually made at the breeding location for more than two years before undergoing evaluation elsewhere, at which point, few...

Phytophthora species associated with forest soils in central and eastern U.S. oak ecosystems

Treesearch

Y. Balci; S. Balci; J. Eggers; W.L. MacDonald; K.W. Gottschalk; J. Juzwik; R. Long

2006-01-01

The existence of native and exotic species of Phytophthora in soils of eastern and central oak ecosystems is largely unknown. This informational void and the potential threat of P. ramorum to eastern oak species provided the impetus for a multiple state survey of soils associated with oak cover types. The initial survey was...

Teacher Perceptions of Head Start Preschool Programs in an Urban Public School District

ERIC Educational Resources Information Center

Perez, Salvador

2017-01-01

An initiative to coordinate early learning programs across a major city in the Midwestern United States was undertaken in 2013. The opinions of teachers regarding effects on instruction and children were not included in the development and implementation of the program. This omission is important because multiple scholars have pointed to the…

Restructuring Schools in Chester Upland, Pennsylvania: An Analysis of State and District Efforts. ECS Policy Brief

ERIC Educational Resources Information Center

Rhim, Lauren Morando

2005-01-01

Restructuring is a process initiated to substantively change the governance, operation and instruction of public schools or districts identified as failing. There are multiple definitions of restructuring, but the common thread binding all restructuring models is a substantive change of the standard operating procedures of a school or an entire…

A Job Too Big for One: Multiple Principals and Other Nontraditional Approaches to School Leadership

ERIC Educational Resources Information Center

Grubb, Norton W.; Flessa, Joseph J.

2006-01-01

Background: Current federal, state, and local school accountability measures as well as policy initiatives that call for improved leadership have placed increasing demands on principals. Many districts face shortages of appropriate candidates for the job; popularly, this shortage is explained by the fact that simply too few hero-principals exist…

Supporting Multiple Cognitive Processing Styles Using Tailored Support Systems

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

Tuan Q. Tran; Karen M. Feigh; Amy R. Pritchett

According to theories of cognitive processing style or cognitive control mode, human performance is more effective when an individual’s cognitive state (e.g., intuition/scramble vs. deliberate/strategic) matches his/her ecological constraints or context (e.g., utilize intuition to strive for a "good-enough" response instead of deliberating for the "best" response under high time pressure). Ill-mapping between cognitive state and ecological constraints are believed to lead to degraded task performance. Consequently, incorporating support systems which are designed to specifically address multiple cognitive and functional states e.g., high workload, stress, boredom, and initiate appropriate mitigation strategies (e.g., reduce information load) is essential to reduce plantmore » risk. Utilizing the concept of Cognitive Control Models, this paper will discuss the importance of tailoring support systems to match an operator's cognitive state, and will further discuss the importance of these ecological constraints in selecting and implementing mitigation strategies for safe and effective system performance. An example from the nuclear power plant industry illustrating how a support system might be tailored to support different cognitive states is included.« less

A Perspective on Multiple Waves of Influenza Pandemics

PubMed Central

Mummert, Anna; Weiss, Howard; Long, Li-Ping; Amigó, José M.; Wan, Xiu-Feng

2013-01-01

Background A striking characteristic of the past four influenza pandemic outbreaks in the United States has been the multiple waves of infections. However, the mechanisms responsible for the multiple waves of influenza or other acute infectious diseases are uncertain. Understanding these mechanisms could provide knowledge for health authorities to develop and implement prevention and control strategies. Materials and Methods We exhibit five distinct mechanisms, each of which can generate two waves of infections for an acute infectious disease. The first two mechanisms capture changes in virus transmissibility and behavioral changes. The third mechanism involves population heterogeneity (e.g., demography, geography), where each wave spreads through one sub-population. The fourth mechanism is virus mutation which causes delayed susceptibility of individuals. The fifth mechanism is waning immunity. Each mechanism is incorporated into separate mathematical models, and outbreaks are then simulated. We use the models to examine the effects of the initial number of infected individuals (e.g., border control at the beginning of the outbreak) and the timing of and amount of available vaccinations. Results Four models, individually or in any combination, reproduce the two waves of the 2009 H1N1 pandemic in the United States, both qualitatively and quantitatively. One model reproduces the two waves only qualitatively. All models indicate that significantly reducing or delaying the initial numbers of infected individuals would have little impact on the attack rate. Instead, this reduction or delay results in a single wave as opposed to two waves. Furthermore, four of these models also indicate that a vaccination program started earlier than October 2009 (when the H1N1 vaccine was initially distributed) could have eliminated the second wave of infection, while more vaccine available starting in October would not have eliminated the second wave. PMID:23637746

A perspective on multiple waves of influenza pandemics.

PubMed

Mummert, Anna; Weiss, Howard; Long, Li-Ping; Amigó, José M; Wan, Xiu-Feng

2013-01-01

A striking characteristic of the past four influenza pandemic outbreaks in the United States has been the multiple waves of infections. However, the mechanisms responsible for the multiple waves of influenza or other acute infectious diseases are uncertain. Understanding these mechanisms could provide knowledge for health authorities to develop and implement prevention and control strategies. We exhibit five distinct mechanisms, each of which can generate two waves of infections for an acute infectious disease. The first two mechanisms capture changes in virus transmissibility and behavioral changes. The third mechanism involves population heterogeneity (e.g., demography, geography), where each wave spreads through one sub-population. The fourth mechanism is virus mutation which causes delayed susceptibility of individuals. The fifth mechanism is waning immunity. Each mechanism is incorporated into separate mathematical models, and outbreaks are then simulated. We use the models to examine the effects of the initial number of infected individuals (e.g., border control at the beginning of the outbreak) and the timing of and amount of available vaccinations. Four models, individually or in any combination, reproduce the two waves of the 2009 H1N1 pandemic in the United States, both qualitatively and quantitatively. One model reproduces the two waves only qualitatively. All models indicate that significantly reducing or delaying the initial numbers of infected individuals would have little impact on the attack rate. Instead, this reduction or delay results in a single wave as opposed to two waves. Furthermore, four of these models also indicate that a vaccination program started earlier than October 2009 (when the H1N1 vaccine was initially distributed) could have eliminated the second wave of infection, while more vaccine available starting in October would not have eliminated the second wave.

Signs of universality in the structure of culture

NASA Astrophysics Data System (ADS)

Băbeanu, Alexandru-Ionuţ; Talman, Leandros; Garlaschelli, Diego

2017-11-01

Understanding the dynamics of opinions, preferences and of culture as whole requires more use of empirical data than has been done so far. It is clear that an important role in driving this dynamics is played by social influence, which is the essential ingredient of many quantitative models. Such models require that all traits are fixed when specifying the "initial cultural state". Typically, this initial state is randomly generated, from a uniform distribution over the set of possible combinations of traits. However, recent work has shown that the outcome of social influence dynamics strongly depends on the nature of the initial state. If the latter is sampled from empirical data instead of being generated in a uniformly random way, a higher level of cultural diversity is found after long-term dynamics, for the same level of propensity towards collective behavior in the short-term. Moreover, if the initial state is randomized by shuffling the empirical traits among people, the level of long-term cultural diversity is in-between those obtained for the empirical and uniformly random counterparts. The current study repeats the analysis for multiple empirical data sets, showing that the results are remarkably similar, although the matrix of correlations between cultural variables clearly differs across data sets. This points towards robust structural properties inherent in empirical cultural states, possibly due to universal laws governing the dynamics of culture in the real world. The results also suggest that this dynamics might be characterized by criticality and involve mechanisms beyond social influence.

Quench dynamics in superconducting nanojunctions: Metastability and dynamical Yang-Lee zeros

NASA Astrophysics Data System (ADS)

Souto, R. Seoane; Martín-Rodero, A.; Yeyati, A. Levy

2017-10-01

We study the charge transfer dynamics following the formation of a phase or voltage biased superconducting nanojunction using a full counting statistics analysis. We demonstrate that the evolution of the zeros of the generating function allows one to identify the population of different many body states much in the same way as the accumulation of Yang-Lee zeros of the partition function in equilibrium statistical mechanics is connected to phase transitions. We give an exact expression connecting the dynamical zeros to the charge transfer cumulants and discuss when an approximation based on "dominant" zeros is valid. We show that, for generic values of the parameters, the system gets trapped into a metastable state characterized by a nonequilibrium population of the many body states which is dependent on the initial conditions. We study in particular the effect of the switching rates in the dynamics showing that, in contrast to intuition, the deviation from thermal equilibrium increases for the slower rates. In the voltage biased case the steady state is reached independent of the initial conditions. Our method allows us to obtain accurate results for the steady state current and noise in quantitative agreement with steady state methods developed to describe the multiple Andreev reflections regime. Finally, we discuss the system dynamics after a sudden voltage drop showing the possibility of tuning the many body states population by an appropriate choice of the initial voltage, providing a feasible experimental way to access the quench dynamics and control the state of the system.

Complex transitions between spike, burst or chaos synchronization states in coupled neurons with coexisting bursting patterns

NASA Astrophysics Data System (ADS)

Gu, Hua-Guang; Chen, Sheng-Gen; Li, Yu-Ye

2015-05-01

We investigated the synchronization dynamics of a coupled neuronal system composed of two identical Chay model neurons. The Chay model showed coexisting period-1 and period-2 bursting patterns as a parameter and initial values are varied. We simulated multiple periodic and chaotic bursting patterns with non-(NS), burst phase (BS), spike phase (SS), complete (CS), and lag synchronization states. When the coexisting behavior is near period-2 bursting, the transitions of synchronization states of the coupled system follows very complex transitions that begins with transitions between BS and SS, moves to transitions between CS and SS, and to CS. Most initial values lead to the CS state of period-2 bursting while only a few lead to the CS state of period-1 bursting. When the coexisting behavior is near period-1 bursting, the transitions begin with NS, move to transitions between SS and BS, to transitions between SS and CS, and then to CS. Most initial values lead to the CS state of period-1 bursting but a few lead to the CS state of period-2 bursting. The BS was identified as chaos synchronization. The patterns for NS and transitions between BS and SS are insensitive to initial values. The patterns for transitions between CS and SS and the CS state are sensitive to them. The number of spikes per burst of non-CS bursting increases with increasing coupling strength. These results not only reveal the initial value- and parameter-dependent synchronization transitions of coupled systems with coexisting behaviors, but also facilitate interpretation of various bursting patterns and synchronization transitions generated in the nervous system with weak coupling strength. Project supported by the National Natural Science Foundation of China (Grant Nos. 11372224 and 11402039) and the Fundamental Research Funds for Central Universities designated to Tongji University (Grant No. 1330219127).

Hierarchical group testing for multiple infections.

PubMed

Hou, Peijie; Tebbs, Joshua M; Bilder, Christopher R; McMahan, Christopher S

2017-06-01

Group testing, where individuals are tested initially in pools, is widely used to screen a large number of individuals for rare diseases. Triggered by the recent development of assays that detect multiple infections at once, screening programs now involve testing individuals in pools for multiple infections simultaneously. Tebbs, McMahan, and Bilder (2013, Biometrics) recently evaluated the performance of a two-stage hierarchical algorithm used to screen for chlamydia and gonorrhea as part of the Infertility Prevention Project in the United States. In this article, we generalize this work to accommodate a larger number of stages. To derive the operating characteristics of higher-stage hierarchical algorithms with more than one infection, we view the pool decoding process as a time-inhomogeneous, finite-state Markov chain. Taking this conceptualization enables us to derive closed-form expressions for the expected number of tests and classification accuracy rates in terms of transition probability matrices. When applied to chlamydia and gonorrhea testing data from four states (Region X of the United States Department of Health and Human Services), higher-stage hierarchical algorithms provide, on average, an estimated 11% reduction in the number of tests when compared to two-stage algorithms. For applications with rarer infections, we show theoretically that this percentage reduction can be much larger. © 2016, The International Biometric Society.

Hierarchical group testing for multiple infections

PubMed Central

Hou, Peijie; Tebbs, Joshua M.; Bilder, Christopher R.; McMahan, Christopher S.

2016-01-01

Summary Group testing, where individuals are tested initially in pools, is widely used to screen a large number of individuals for rare diseases. Triggered by the recent development of assays that detect multiple infections at once, screening programs now involve testing individuals in pools for multiple infections simultaneously. Tebbs, McMahan, and Bilder (2013, Biometrics) recently evaluated the performance of a two-stage hierarchical algorithm used to screen for chlamydia and gonorrhea as part of the Infertility Prevention Project in the United States. In this article, we generalize this work to accommodate a larger number of stages. To derive the operating characteristics of higher-stage hierarchical algorithms with more than one infection, we view the pool decoding process as a time-inhomogeneous, finite-state Markov chain. Taking this conceptualization enables us to derive closed-form expressions for the expected number of tests and classification accuracy rates in terms of transition probability matrices. When applied to chlamydia and gonorrhea testing data from four states (Region X of the United States Department of Health and Human Services), higher-stage hierarchical algorithms provide, on average, an estimated 11 percent reduction in the number of tests when compared to two-stage algorithms. For applications with rarer infections, we show theoretically that this percentage reduction can be much larger. PMID:27657666

Multiple steady states in atmospheric chemistry

NASA Technical Reports Server (NTRS)

Stewart, Richard W.

1993-01-01

The equations describing the distributions and concentrations of trace species are nonlinear and may thus possess more than one solution. This paper develops methods for searching for multiple physical solutions to chemical continuity equations and applies these to subsets of equations describing tropospheric chemistry. The calculations are carried out with a box model and use two basic strategies. The first strategy is a 'search' method. This involves fixing model parameters at specified values, choosing a wide range of initial guesses at a solution, and using a Newton-Raphson technique to determine if different initial points converge to different solutions. The second strategy involves a set of techniques known as homotopy methods. These do not require an initial guess, are globally convergent, and are guaranteed, in principle, to find all solutions of the continuity equations. The first method is efficient but essentially 'hit or miss' in the sense that it cannot guarantee that all solutions which may exist will be found. The second method is computationally burdensome but can, in principle, determine all the solutions of a photochemical system. Multiple solutions have been found for models that contain a basic complement of photochemical reactions involving O(x), HO(x), NO(x), and CH4. In the present calculations, transitions occur between stable branches of a multiple solution set as a control parameter is varied. These transitions are manifestations of hysteresis phenomena in the photochemical system and may be triggered by increasing the NO flux or decreasing the CH4 flux from current mean tropospheric levels.

Application of the Constrained Admissible Region Multiple Hypothesis Filter to Initial Orbit Determination of a Break-up

NASA Astrophysics Data System (ADS)

Kelecy, Tom; Shoemaker, Michael; Jah, Moriba

2013-08-01

A break-up in Low Earth Orbit (LEO) is simulated for 10 objects having area-to-mass ratios (AMR's) ranging from 0.1-10.0 m2/kg. The Constrained Admissible Region Multiple Hypothesis Filter (CAR-MHF) is applied to determining and characterizing the orbit and atmospheric drag parameters (CdA/m) simultaneously for each of the 10 objects with no a priori orbit or drag information. The results indicate that CAR-MHF shows promise for accurate, unambiguous and autonomous determination of the orbit and drag states.

Non-AUG translation: a new start for protein synthesis in eukaryotes

PubMed Central

Kearse, Michael G.; Wilusz, Jeremy E.

2017-01-01

Although it was long thought that eukaryotic translation almost always initiates at an AUG start codon, recent advancements in ribosome footprint mapping have revealed that non-AUG start codons are used at an astonishing frequency. These non-AUG initiation events are not simply errors but instead are used to generate or regulate proteins with key cellular functions; for example, during development or stress. Misregulation of non-AUG initiation events contributes to multiple human diseases, including cancer and neurodegeneration, and modulation of non-AUG usage may represent a novel therapeutic strategy. It is thus becoming increasingly clear that start codon selection is regulated by many trans-acting initiation factors as well as sequence/structural elements within messenger RNAs and that non-AUG translation has a profound impact on cellular states. PMID:28982758

Charge transfer in single and multiple scattering events at metal surfaces: a wavepacket study of the Na(+)/Cu(100) system.

PubMed

Sindona, A; Pisarra, M; Maletta, S; Riccardi, P; Falcone, G

2010-12-01

Resonant neutralization of hyperthermal energy Na(+) ions impinging on Cu(100) surfaces is studied, focusing on two specific collision events: one in which the projectile is reflected off the surface, the other in which the incident atom penetrates the outer surface layers initiating a series of scattering processes, within the target, and coming out together with a single surface atom. A semi-empirical model potential is adopted that embeds: (i) the electronic structure of the sample, (ii) the central field of the projectile, and (iii) the contribution of the Cu atom ejected in multiple scattering events. The evolution of the ionization orbital of the scattered atom is simulated, backwards in time, using a wavepacket propagation algorithm. The output of the approach is the neutralization probability, obtained by projecting the time-reversed valence wavefunction of the projectile onto the initially filled conduction band states. The results are in agreement with available data from the literature (Keller et al 1995 Phys. Rev. Lett. 75 1654) indicating that the motion of surface atoms, exiting the targets with kinetic energies of the order of a few electronvolts, plays a significant role in the final charge state of projectiles.

MULTIPLE CURRENT SHEET SYSTEMS IN THE OUTER HELIOSPHERE: ENERGY RELEASE AND TURBULENCE

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

Burgess, D.; Gingell, P. W.; Matteini, L.

2016-05-01

In the outer heliosphere, beyond the solar wind termination shock, it is expected that the warped heliospheric current sheet forms a region of closely packed, multiple, thin current sheets. Such a system may be subject to the ion-kinetic tearing instability, and hence may generate magnetic islands and hot populations of ions associated with magnetic reconnection. Reconnection processes in this environment have important implications for local particle transport, and for particle acceleration at reconnection sites and in turbulence. We study this complex environment by means of three-dimensional hybrid simulations over long timescales, in order to capture the evolution from linear growthmore » of the tearing instability to a fully developed turbulent state at late times. The final state develops from the highly ordered initial state via both forward and inverse cascades. Component and spectral anisotropy in the magnetic fluctuations is present when a guide field is included. The inclusion of a population of newborn interstellar pickup protons does not strongly affect these results. Finally, we conclude that reconnection between multiple current sheets can act as an important source of turbulence in the outer heliosphere, with implications for energetic particle acceleration and propagation.« less

New method for finding multiple meaningful trajectories

NASA Astrophysics Data System (ADS)

Bao, Zhonghao; Flachs, Gerald M.; Jordan, Jay B.

1995-07-01

Mathematical foundations and algorithms for efficiently finding multiple meaningful trajectories (FMMT) in a sequence of digital images are presented. A meaningful trajectory is motion created by a sentient being or by a device under the control of a sentient being. It is smooth and predictable over short time intervals. A meaningful trajectory can suddenly appear or disappear in sequence images. The development of the FMMT is based on these assumptions. A finite state machine in the FMMT is used to model the trajectories under the conditions of occlusions and false targets. Each possible trajectory is associated with an initial state of a finite state machine. When two frames of data are available, a linear predictor is used to predict the locations of all possible trajectories. All trajectories within a certain error bound are moved to a monitoring trajectory state. When trajectories attain three consecutive good predictions, they are moved to a valid trajectory state and considered to be locked into a tracking mode. If an object is occluded while in the valid trajectory state, the predicted position is used to continue to track; however, the confidence in the trajectory is lowered. If the trajectory confidence falls below a lower limit, the trajectory is terminated. Results are presented that illustrate the FMMT applied to track multiple munitions fired from a missile in a sequence of images. Accurate trajectories are determined even in poor images where the probabilities of miss and false alarm are very high.

The need and approach for characterization - U.S. air force perspectives on materials state awareness

NASA Astrophysics Data System (ADS)

Aldrin, John C.; Lindgren, Eric A.

2018-04-01

This paper expands on the objective and motivation for NDE-based characterization and includes a discussion of the current approach using model-assisted inversion being pursued within the Air Force Research Laboratory (AFRL). This includes a discussion of the multiple model-based methods that can be used, including physics-based models, deep machine learning, and heuristic approaches. The benefits and drawbacks of each method is reviewed and the potential to integrate multiple methods is discussed. Initial successes are included to highlight the ability to obtain quantitative values of damage. Additional steps remaining to realize this capability with statistical metrics of accuracy are discussed, and how these results can be used to enable probabilistic life management are addressed. The outcome of this initiative will realize the long-term desired capability of NDE methods to provide quantitative characterization to accelerate certification of new materials and enhance life management of engineered systems.

A LOWER INITIAL ABUNDANCE OF SHORT-LIVED {sup 41}Ca IN THE EARLY SOLAR SYSTEM AND ITS IMPLICATIONS FOR SOLAR SYSTEM FORMATION

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

Liu, Ming-Chang; Chaussidon, Marc; Srinivasan, Gopalan

The short-lived radionuclide {sup 41}Ca plays an important role in constraining the immediate astrophysical environment and the formation timescale of the nascent solar system due to its extremely short half-life (0.1 Myr). Nearly 20 years ago, the initial ratio of {sup 41}Ca/{sup 40}Ca in the solar system was determined to be (1.41 {+-} 0.14) Multiplication-Sign 10{sup -8}, primarily based on two Ca-Al-rich Inclusions (CAIs) from the CV chondrite Efremovka. With an advanced analytical technique for isotopic measurements, we reanalyzed the potassium isotopic compositions of the two Efremovka CAIs and inferred the initial ratios of {sup 41}Ca/{sup 40}Ca to be (2.6more » {+-} 0.9) Multiplication-Sign 10{sup -9} and (1.4 {+-} 0.6) Multiplication-Sign 10{sup -9} (2{sigma}), a factor of 7-10 lower than the previously inferred value. Considering possible thermal processing that led to lower {sup 26}Al/{sup 27}Al ratios in the two CAIs, we propose that the true solar system initial value of {sup 41}Ca/{sup 40}Ca should have been {approx}4.2 Multiplication-Sign 10{sup -9}. Synchronicity could have existed between {sup 26}Al and {sup 41}Ca, indicating a uniform distribution of the two radionuclides at the time of CAI formation. The new initial {sup 41}Ca abundance is 4-16 times lower than the calculated value for steady-state galactic nucleosynthesis. Therefore, {sup 41}Ca could have originated as part of molecular cloud materials with a free decay time of 0.2-0.4 Myr. Alternative possibilities, such as a last-minute input from a stellar source and early solar system irradiation, could not be definitively ruled out. This underscores the need for more data from diverse CAIs to determine the true astrophysical origin of {sup 41}Ca.« less

Alabama Institute for Deaf and Blind Biodiesel Project Green

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

Edmiston, Jessica L

2012-09-28

Through extensive collaboration, Alabama Institute for Deaf and Blind (AIDB) is Alabama's first educational entity to initiate a biodiesel public education, student training and production program, Project Green. With state and national replication potential, Project Green benefits local businesses and city infrastructures within a 120-mile radius; provides alternative education to Alabama school systems and to schools for the deaf and blind in Appalachian States; trains students with sensory and/or multiple disabilities in the acquisition and production of biodiesel; and educates the external public on alternative fuels benefits.

Minimal gain marching schemes: searching for unstable steady-states with unsteady solvers

NASA Astrophysics Data System (ADS)

de S. Teixeira, Renan; S. de B. Alves, Leonardo

2017-12-01

Reference solutions are important in several applications. They are used as base states in linear stability analyses as well as initial conditions and reference states for sponge zones in numerical simulations, just to name a few examples. Their accuracy is also paramount in both fields, leading to more reliable analyses and efficient simulations, respectively. Hence, steady-states usually make the best reference solutions. Unfortunately, standard marching schemes utilized for accurate unsteady simulations almost never reach steady-states of unstable flows. Steady governing equations could be solved instead, by employing Newton-type methods often coupled with continuation techniques. However, such iterative approaches do require large computational resources and very good initial guesses to converge. These difficulties motivated the development of a technique known as selective frequency damping (SFD) (Åkervik et al. in Phys Fluids 18(6):068102, 2006). It adds a source term to the unsteady governing equations that filters out the unstable frequencies, allowing a steady-state to be reached. This approach does not require a good initial condition and works well for self-excited flows, where a single nonzero excitation frequency is selected by either absolute or global instability mechanisms. On the other hand, it seems unable to damp stationary disturbances. Furthermore, flows with a broad unstable frequency spectrum might require the use of multiple filters, which delays convergence significantly. Both scenarios appear in convectively, absolutely or globally unstable flows. An alternative approach is proposed in the present paper. It modifies the coefficients of a marching scheme in such a way that makes the absolute value of its linear gain smaller than one within the required unstable frequency spectra, allowing the respective disturbance amplitudes to decay given enough time. These ideas are applied here to implicit multi-step schemes. A few chosen test cases shows that they enable convergence toward solutions that are unstable to stationary and oscillatory disturbances, with either a single or multiple frequency content. Finally, comparisons with SFD are also performed, showing significant reduction in computer cost for complex flows by using the implicit multi-step MGM schemes.

Multiple parton interaction studies at DØ

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

Lincoln, D.

Here, we present the results of studies of multiparton interactions done by the DØ collaboration using the Fermilab Tevatron at a center of mass energy of 1.96 TeV. We also present three analyses, involving three distinct final signatures: (a) a photon with at least 3 jets ( γ + 3jets), (b) a photon with a bottom or charm quark tagged jet and at least 2 other jets ( γ + b/c + 2jets), and (c) two J/ ψ mesons. The fraction of photon + jet events initiated by double parton scattering is about 20%, while the fraction for events inmore » which two J/ ψ mesons were produced is 30 ± 10. While the two measurements are statistically compatible, the difference might indicate differences in the quark and gluon distribution within a nucleon. Finally, this speculation originates from the fact that photon + jet events are created by collisions with quarks in the initial states, while J/ ψ events are produced preferentially by a gluonic initial state.« less

Multiple parton interaction studies at DØ

DOE PAGES

Lincoln, D.

2016-04-01

Here, we present the results of studies of multiparton interactions done by the DØ collaboration using the Fermilab Tevatron at a center of mass energy of 1.96 TeV. We also present three analyses, involving three distinct final signatures: (a) a photon with at least 3 jets ( γ + 3jets), (b) a photon with a bottom or charm quark tagged jet and at least 2 other jets ( γ + b/c + 2jets), and (c) two J/ ψ mesons. The fraction of photon + jet events initiated by double parton scattering is about 20%, while the fraction for events inmore » which two J/ ψ mesons were produced is 30 ± 10. While the two measurements are statistically compatible, the difference might indicate differences in the quark and gluon distribution within a nucleon. Finally, this speculation originates from the fact that photon + jet events are created by collisions with quarks in the initial states, while J/ ψ events are produced preferentially by a gluonic initial state.« less

Flow processes on the catchment scale - modeling of initial structural states and hydrological behavior in an artificial exemplary catchment

NASA Astrophysics Data System (ADS)

Maurer, Thomas; Caviedes-Voullième, Daniel; Hinz, Christoph; Gerke, Horst H.

2017-04-01

Landscapes that are heavily disturbed or newly formed by either natural processes or human activity are in a state of disequilibrium. Their initial development is thus characterized by highly dynamic processes under all climatic conditions. The primary distribution and structure of the solid phase (i.e. mineral particles forming the pore space) is one of the decisive factors for the development of hydrological behavior of the eco-hydrological system and therefore (co-) determining for its - more or less - stable final state. The artificially constructed ‚Hühnerwasser' catchment (a 6 ha area located in the open-cast lignite mine Welzow-Süd, southern Brandenburg, Germany) is a landscape laboratory where the initial eco-hydrological development is observed since 2005. The specific formation (or construction) processes generated characteristic sediment structures and distributions, resulting in a spatially heterogeneous initial state of the catchment. We developed a structure generator that simulates the characteristic distribution of the solid phase for such constructed landscapes. The program is able to generate quasi-realistic structures and sediment compositions on multiple spatial levels (1 cm up to 100 m scale). The generated structures can be i) conditioned to actual measurement values (e.g., soil texture and bulk distribution); ii) stochastically generated, and iii) calculated deterministically according to the geology and technical processes at the excavation site. Results are visualized using the GOCAD software package and the free software Paraview. Based on the 3D-spatial sediment distributions, effective hydraulic van-Genuchten parameters are calculated using pedotransfer functions. The hydraulic behavior of different sediment distribution (i.e. versions or variations of the catchment's porous body) is calculated using a numerical model developed by one of us (Caviedes-Voullième). Observation data are available from catchment monitoring are available for i) determining the boundary conditions (e.g., precipitation), and ii) the calibration / validation of the model (catchment discharge, ground water). The analysis of multiple sediment distribution scenarios should allow to approximately determine the influx of starting conditions on initial development of hydrological behavior. We present first flow modeling results for a reference (conditioned) catchment model and variations thereof. We will also give an outlook on further methodical development of our approach.

Interfacing the Ab initio multiple spawning method with electronic structure methods in GAMESS: Photodecay of trans-Azomethane

DOE PAGES

Gaenko, Alexander; DeFusco, Albert; Varganov, Sergey A.; ...

2014-10-20

This work presents a nonadiabatic molecular dynamics study of the nonradiative decay of photoexcited trans-azomethane, using the ab initio multiple spawning (AIMS) program that has been interfaced with the General Atomic and Molecular Electronic Structure System (GAMESS) quantum chemistry package for on-the-fly electronic structure evaluation. The interface strategy is discussed, and the capabilities of the combined programs are demonstrated with a nonadiabatic molecular dynamics study of the nonradiative decay of photoexcited trans-azomethane. Energies, gradients, and nonadiabatic coupling matrix elements were obtained with the state-averaged complete active space self-consistent field method, as implemented in GAMESS. The influence of initial vibrational excitationmore » on the outcome of the photoinduced isomerization is explored. Increased vibrational excitation in the CNNC torsional mode shortens the excited state lifetime. Depending on the degree of vibrational excitation, the excited state lifetime varies from ~60–200 fs. As a result, these short lifetimes are in agreement with time-resolved photoionization mass spectroscopy experiments.« less

Reprint of: Ionization probabilities of Ne, Ar, Kr, and Xe by proton impact for different initial states and impact energies

NASA Astrophysics Data System (ADS)

Montanari, C. C.; Miraglia, J. E.

2018-01-01

In this contribution we present ab initio results for ionization total cross sections, probabilities at zero impact parameter, and impact parameter moments of order +1 and -1 of Ne, Ar, Kr, and Xe by proton impact in an extended energy range from 100 keV up to 10 MeV. The calculations were performed by using the continuum distorted wave eikonal initial state approximation (CDW-EIS) for energies up to 1 MeV, and using the first Born approximation for larger energies. The convergence of the CDW-EIS to the first Born above 1 MeV is clear in the present results. Our inner-shell ionization cross sections are compared with the available experimental data and with the ECPSSR results. We also include in this contribution the values of the ionization probabilities at the origin, and the impact parameter dependence. These values have been employed in multiple ionization calculations showing very good description of the experimental data. Tables of the ionization probabilities are presented, disaggregated for the different initial bound states, considering all the shells for Ne and Ar, the M-N shells of Kr and the N-O shells of Xe.

Multiple treatments yield early success in a shortleaf pine woodland restoration project in the Missouri Ozarks

Treesearch

Matthew G. Olson; Elizabeth K. Olson

2016-01-01

Shortleaf pine woodland communities were more extensive in the southeastern Missouri Ozarks prior to Euro-American settlement than today. In 2000, the Missouri Department of Conservation initiated a shortleaf pine woodland restoration project on state land in the Ozarks of southeast Missouri at an area called the Midco Pine Flats Restoration Area. The purpose of this...

On the Evolution of Terrestrial Planets: Implications of Evolutionary Paths and Evolving Lid-States

NASA Astrophysics Data System (ADS)

Weller, M. B.; Lenardic, A.

2015-12-01

Growing geodynamic and geochemical evidence suggests that plate tectonics may not have operated on the early Earth, with both the timing of its onset and the length of its activity far from certain [e.g., 1, 2, and references therein]. Accordingly, information from current observations and processes have the potential of sampling portions of the Earth that has both formed under and been modified by differing tectonic regimes. Here we use coupled 3D mantle convection and planetary tectonics simulations to explore evolutionary paths and planetary tectonic regimes. Early in the geologic lifetime of a terrestrial planet, high mantle temperatures favour stagnant-lids. As radiogenics decay, an initial stagnant-lid may yield into a high temperature mobile-lid state. The transition from an initial stagnant-lid is a function of yield strength, in addition to both internal and surface temperatures. Each lid-state has specific diagnostics and implications for internal parameters, and consequently planetary evolution. The implication within this framework is that a system with a different thermal evolution has the potential to migrate through tectonic regimes at the same 'thermal time' (e.g. temperature), but very different 'temporal times'. This indicate that multiple modes of convection and surface tectonics can potentially operate on a single planetary body at different times in its evolution, as consequence of changing internal parameters, surface temperatures, and differing thermal histories. We will discuss the implications of terrestrial worlds that can alternate, and be offset between multiple tectonic states over giga-year timescales. [1] O'Neill et. al. (2013b) Geol. Soc. London; [2] Weller et al. (2015) EPSL

New York State's "Assets Coming Together (ACT) for Youth": a statewide approach effects community change.

PubMed

Riser, Marta H; Mesler, Kristine; Tallon, Thomas C; Birkhead, Guthrie S

2006-11-01

The New York State Department of Health launched an innovative initiative, Assets Coming Together (ACT) for Youth, implemented in 2000, as a public health strategy to promote youth development (YD) as a means to improve health outcomes for youth. ACT for Youth shifted the focus from problems and problem reduction to assets and strength-based means of improving health by enhancing opportunities and supports in communities for all youth and their families. ACT for Youth is innovative in its emphasis on community building and community change at multiple levels. This descriptive report mentions development, implementation, specific objectives, and highlights of accomplishments in mobilizing communities around YD. Lessons learned over the first 5 years of the initiative are reviewed, with emphasis on the elements of successful health department YD programming. From this foundation, New York State hopes to be in the vanguard of utilizing YD as a public health improvement strategy and hopes that others will follow.

Hydrodynamic Flow Fluctuations in √sNN = 5:02 TeV PbPbCollisions

NASA Astrophysics Data System (ADS)

Castle, James R.

The collective, anisotropic expansion of the medium created in ultrarelativistic heavy-ion collisions, known as flow, is characterized through a Fourier expansion of the final-state azimuthal particle density. In the Fourier expansion, flow harmonic coefficients vn correspond to shape components in the final-state particle density, which are a consequence of similar spatial anisotropies in the initial-state transverse energy density of a collision. Flow harmonic fluctuations are studied for PbPb collisions at √sNN = 5.02 TeV using the CMS detector at the CERN LHC. Flow harmonic probability distributions p( vn) are obtained using particles with 0.3 < pT < 3.0 GeV/c and ∥eta∥ < 1.0 by removing finite-multiplicity resolution effects from the observed azimuthal particle density through an unfolding procedure. Cumulant elliptic flow harmonics (n = 2) are determined from the moments of the unfolded p(v2) distributions and used to construct observables in 5% wide centrality bins up to 60% that relate to the initial-state spatial anisotropy. Hydrodynamic models predict that fluctuations in the initial-state transverse energy density will lead to a non-Gaussian component in the elliptic flow probability distributions that manifests as a negative skewness. A statistically significant negative skewness is observed for all centrality bins as evidenced by a splitting between the higher-order cumulant elliptic flow harmonics. The unfolded p (v2) distributions are transformed assuming a linear relationship between the initial-state spatial anisotropy and final-state flow and are fitted with elliptic power law and Bessel Gaussian parametrizations to infer information on the nature of initial-state fluctuations. The elliptic power law parametrization is found to provide a more accurate description of the fluctuations than the Bessel-Gaussian parametrization. In addition, the event-shape engineering technique, where events are further divided into classes based on an observed ellipticity, is used to study fluctuation-driven differences in the initial-state spatial anisotropy for a given collision centrality that would otherwise be destroyed by event-averaging techniques. Correlations between the first and second moments of p( vn) distributions and event ellipticity are measured for harmonic orders n = 2 - 4 by coupling event-shape engineering to the unfolding technique.

Enzyme catalysis captured using multiple structures from one crystal at varying temperatures.

PubMed

Horrell, Sam; Kekilli, Demet; Sen, Kakali; Owen, Robin L; Dworkowski, Florian S N; Antonyuk, Svetlana V; Keal, Thomas W; Yong, Chin W; Eady, Robert R; Hasnain, S Samar; Strange, Richard W; Hough, Michael A

2018-05-01

High-resolution crystal structures of enzymes in relevant redox states have transformed our understanding of enzyme catalysis. Recent developments have demonstrated that X-rays can be used, via the generation of solvated electrons, to drive reactions in crystals at cryogenic temperatures (100 K) to generate 'structural movies' of enzyme reactions. However, a serious limitation at these temperatures is that protein conformational motion can be significantly supressed. Here, the recently developed MSOX (multiple serial structures from one crystal) approach has been applied to nitrite-bound copper nitrite reductase at room temperature and at 190 K, close to the glass transition. During both series of multiple structures, nitrite was initially observed in a 'top-hat' geometry, which was rapidly transformed to a 'side-on' configuration before conversion to side-on NO, followed by dissociation of NO and substitution by water to reform the resting state. Density functional theory calculations indicate that the top-hat orientation corresponds to the oxidized type 2 copper site, while the side-on orientation is consistent with the reduced state. It is demonstrated that substrate-to-product conversion within the crystal occurs at a lower radiation dose at 190 K, allowing more of the enzyme catalytic cycle to be captured at high resolution than in the previous 100 K experiment. At room temperature the reaction was very rapid, but it remained possible to generate and characterize several structural states. These experiments open up the possibility of obtaining MSOX structural movies at multiple temperatures (MSOX-VT), providing an unparallelled level of structural information during catalysis for redox enzymes.

MSClique: Multiple Structure Discovery through the Maximum Weighted Clique Problem.

PubMed

Sanroma, Gerard; Penate-Sanchez, Adrian; Alquézar, René; Serratosa, Francesc; Moreno-Noguer, Francesc; Andrade-Cetto, Juan; González Ballester, Miguel Ángel

2016-01-01

We present a novel approach for feature correspondence and multiple structure discovery in computer vision. In contrast to existing methods, we exploit the fact that point-sets on the same structure usually lie close to each other, thus forming clusters in the image. Given a pair of input images, we initially extract points of interest and extract hierarchical representations by agglomerative clustering. We use the maximum weighted clique problem to find the set of corresponding clusters with maximum number of inliers representing the multiple structures at the correct scales. Our method is parameter-free and only needs two sets of points along with their tentative correspondences, thus being extremely easy to use. We demonstrate the effectiveness of our method in multiple-structure fitting experiments in both publicly available and in-house datasets. As shown in the experiments, our approach finds a higher number of structures containing fewer outliers compared to state-of-the-art methods.

Multiple stepwise refolding of immunoglobulin domain I27 upon force quench depends on initial conditions

PubMed Central

Li, Mai Suan; Hu, Chin-Kun; Klimov, Dmitri K.; Thirumalai, D.

2006-01-01

Mechanical folding trajectories for polyproteins starting from initially stretched conformations generated by single-molecule atomic force microscopy experiments [Fernandez, J. M. & Li, H. (2004) Science 303, 1674–1678] show that refolding, monitored by the end-to-end distance, occurs in distinct multiple stages. To clarify the molecular nature of folding starting from stretched conformations, we have probed the folding dynamics, upon force quench, for the single I27 domain from the muscle protein titin by using a Cα-Go model. Upon temperature quench, collapse and folding of I27 are synchronous. In contrast, refolding from stretched initial structures not only increases the folding and collapse time scales but also decouples the two kinetic processes. The increase in the folding times is associated primarily with the stretched state to compact random coil transition. Surprisingly, force quench does not alter the nature of the refolding kinetics, but merely increases the height of the free-energy folding barrier. Force quench refolding times scale as \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\tau}_{F}\\approx {\\tau}_{F}^{0}{\\mathrm{exp}}(f_{q}{\\Delta}x_{f}/k_{{\\mathrm{B}}}T)\\end{equation*}\\end{document}, where Δxf ≈ 0.6 nm is the location of the average transition state along the reaction coordinate given by end-to-end distance. We predict that τF and the folding mechanism can be dramatically altered by the initial and/or final values of force. The implications of our results for design and analysis of experiments are discussed. PMID:16373511

Models of initial training and pathways to registration: a selective review of policy in professional regulation.

PubMed

Fealy, Gerard M; Carney, Marie; Drennan, Jonathan; Treacy, Margaret; Burke, Jacqueline; O'Connell, Dympna; Howley, Breeda; Clancy, Alison; McHugh, Aine; Patton, Declan; Sheerin, Fintan

2009-09-01

To provide a synthesis of literature on international policy concerning professional regulation in nursing and midwifery, with reference to routes of entry into training and pathways to licensure. Internationally, there is evidence of multiple points of entry into initial training, multiple divisions of the professional register and multiple pathways to licensure. Policy documents and commentary articles concerned with models of initial training and pathways to licensure were reviewed. Item selection, quality appraisal and data extraction were undertaken and documentary analysis was performed on all retrieved texts. Case studies of five Western countries indicate no single uniform system of routes of entry into initial training and no overall consensus regarding the optimal model of initial training. Multiple regulatory systems, with multiple routes of entry into initial training and multiple pathways to licensure pose challenges, in terms of achieving commonly-agreed understandings of practice competence. The variety of models of initial training present nursing managers with challenges in the recruitment and deployment of personnel trained in many different jurisdictions. Nursing managers need to consider the potential for considerable variation in competency repertoires among nurses trained in generic and specialist initial training models.

Emerging geomorphic approaches to guide river management practices

NASA Astrophysics Data System (ADS)

Brierley, Gary; Hooke, Janet

2015-12-01

Humans have been modifying river systems across much of the world for many thousands of years. Initially, piecemeal impacts inadvertently affected particular parts of landscapes. Subsequently, many rivers have been subjected to multiple layers of human disturbance, and changes have become widespread and systematic. Increasingly, human impacts reflect deliberative actions as part of river management programmes. These activities entail significant choices in determining the desirable (or acceptable) state and behavioural regime of a river. Typically, contemporary decision-making reflects negotiations among multiple stakeholders, seeking to provide balanced approaches to the management of socio-economic, cultural, and environmental values (e.g. Jähnig et al., 2011).

Law of Conservation of Muons

DOE R&D Accomplishments Database

Feinberg, G.; Weinberg, S.

1961-02-01

A multiplicative selection rule for mu meson-electron transitions is proposed. A "muon parity" = -1 is considered for the muon and its neutrino, while the "muon parity" for all other particles is +1. The selection rule then states that (-1) exp(no. of initial (-1) parity particles) = (-1) exp(no. of final (-1) parity particles). Several reactions that are forbidden by an additive law but allowed by the multiplicative law are suggested; these reactions include mu{sup +} .> e{sup +} + nu{sub mu} + {ovr nu}{sub e}, e{sup -} + e{sup -} .> mu{sup -} + mu{sup -}, and muonium .> antimuonium (mu{sup +} + e{sup -} .> mu{sup -} + e{sup +}). An intermediate-boson hypothesis is suggested. (T.F.H.)

The Next Generation of Users: Prevalence and Longitudinal Patterns of Tobacco Use Among US Young Adults

PubMed Central

Williams, Valerie; Rath, Jessica; Villanti, Andrea C.; Vallone, Donna

2014-01-01

Objectives. We monitored the prevalence and patterns of use of the array of tobacco products available to young adults, who are at risk for initiation and progression to established tobacco use. Methods. We used data from waves 1 to 3 of GfK’s KnowledgePanel (2011–2012), a nationally representative cohort of young adults aged 18 to 34 years (n = 2144). We examined prevalence and patterns of tobacco product use over time, associated demographics, and state-level tobacco policy. We used multivariable logistic regression to determine predictors of initiation of cigarettes as well as noncombustible and other combustible products. Results. The prevalence of ever tobacco use rose from 57.28% at wave 1 to 67.43% at wave 3. Use of multiple products was the most common pattern (66.39% of tobacco users by wave 3). Predictors of initiation differed by product type and included age, race/ethnicity, policy, and use of other tobacco products. Conclusions. Tobacco use is high among young adults and many are using multiple products. Efforts to implement policy and educate young adults about the risks associated with new and emerging products are critical to prevent increased initiation of tobacco use. PMID:24922152

The AGING Initiative experience: a call for sustained support for team science networks.

PubMed

Garg, Tullika; Anzuoni, Kathryn; Landyn, Valentina; Hajduk, Alexandra; Waring, Stephen; Hanson, Leah R; Whitson, Heather E

2018-05-18

Team science, defined as collaborative research efforts that leverage the expertise of diverse disciplines, is recognised as a critical means to address complex healthcare challenges, but the practical implementation of team science can be difficult. Our objective is to describe the barriers, solutions and lessons learned from our team science experience as applied to the complex and growing challenge of multiple chronic conditions (MCC). MCC is the presence of two or more chronic conditions that have a collective adverse effect on health status, function or quality of life, and that require complex healthcare management, decision-making or coordination. Due to the increasing impact on the United States society, MCC research has been identified as a high priority research area by multiple federal agencies. In response to this need, two national research entities, the Healthcare Systems Research Network (HCSRN) and the Claude D. Pepper Older Americans Independence Centers (OAIC), formed the Advancing Geriatrics Infrastructure and Network Growth (AGING) Initiative to build nationwide capacity for MCC team science. This article describes the structure, lessons learned and initial outcomes of the AGING Initiative. We call for funding mechanisms to sustain infrastructures that have demonstrated success in fostering team science and innovation in translating findings to policy change necessary to solve complex problems in healthcare.

Flight initiation and maintenance deficits in flies with genetically altered biogenic amine levels.

PubMed

Brembs, Björn; Christiansen, Frauke; Pflüger, Hans Joachim; Duch, Carsten

2007-10-10

Insect flight is one of the fastest, most intense and most energy-demanding motor behaviors. It is modulated on multiple levels by the biogenic amine octopamine. Within the CNS, octopamine acts directly on the flight central pattern generator, and it affects motivational states. In the periphery, octopamine sensitizes sensory receptors, alters muscle contraction kinetics, and enhances flight muscle glycolysis. This study addresses the roles for octopamine and its precursor tyramine in flight behavior by genetic and pharmacological manipulation in Drosophila. Octopamine is not the natural signal for flight initiation because flies lacking octopamine [tyramine-beta-hydroxylase (TbetaH) null mutants] can fly. However, they show profound differences with respect to flight initiation and flight maintenance compared with wild-type controls. The morphology, kinematics, and development of the flight machinery are not impaired in TbetaH mutants because wing-beat frequencies and amplitudes, flight muscle structure, and overall dendritic structure of flight motoneurons are unaffected in TbetaH mutants. Accordingly, the flight behavior phenotypes can be rescued acutely in adult flies. Flight deficits are rescued by substituting octopamine but also by blocking the receptors for tyramine, which is enriched in TbetaH mutants. Conversely, ablating all neurons containing octopamine or tyramine phenocopies TbetaH mutants. Therefore, both octopamine and tyramine systems are simultaneously involved in regulating flight initiation and maintenance. Different sets of rescue experiments indicate different sites of action for both amines. These findings are consistent with a complex system of multiple amines orchestrating the control of motor behaviors on multiple levels rather than single amines eliciting single behaviors.

Prediction of Hydrological Drought: What Can We Learn From Continental-Scale Offline Simulations?

NASA Technical Reports Server (NTRS)

Koster, Randal; Mahanama, Sarith; Livneh, Ben; Lettenmaier, Dennis; Reichle, Rolf

2011-01-01

Land surface model experiments are used to quantify, across the coterminous United States, the contributions (isolated and combined) of soil moisture and snowpack initialization to the skill of seasonal streamflow forecasts at multiple leads and for different start dates. Forecasted streamflows are compared to naturalized streamflow observations where available and to synthetic (model-generated) streamflow data elsewhere. We find that snow initialization has a major impact on skill in the mountainous western U.S. and in a portion of the northern Great Plains; a mid-winter (January 1) initialization of snow in these areas leads to significant skill in the spring melting season. Soil moisture initialization also contributes to skill, and although the maximum contributions are not as large as those seen for snow initialization, the soil moisture contributions extend across a much broader geographical area. Soil moisture initialization can contribute to skill at long leads (up to 5 or 6 months), particularly for forecasts issued during winter.

Theoretical investigations of quantum correlations in NMR multiple-pulse spin-locking experiments

NASA Astrophysics Data System (ADS)

Gerasev, S. A.; Fedorova, A. V.; Fel'dman, E. B.; Kuznetsova, E. I.

2018-04-01

Quantum correlations are investigated theoretically in a two-spin system with the dipole-dipole interactions in the NMR multiple-pulse spin-locking experiments. We consider two schemes of the multiple-pulse spin-locking. The first scheme consists of π /2-pulses only and the delays between the pulses can differ. The second scheme contains φ-pulses (0<φ <π ) and has equal delays between them. We calculate entanglement for both schemes for an initial separable state. We show that entanglement is absent for the first scheme at equal delays between π /2-pulses at arbitrary temperatures. Entanglement emerges after several periods of the pulse sequence in the second scheme at φ =π /4 at milliKelvin temperatures. The necessary number of the periods increases with increasing temperature. We demonstrate the dependence of entanglement on the number of the periods of the multiple-pulse sequence. Quantum discord is obtained for the first scheme of the multiple-pulse spin-locking experiment at different temperatures.

Response to Early AED Therapy and Its Prognostic Implications

PubMed Central

French, Jacqueline A.

2002-01-01

Determining the prognosis of patients when they first present with epilepsy is a difficult task. Several clinical studies have shed light on this very important topic. Potential predictors of the refractory state, including seizure etiology, duration of epilepsy before treatment, and epilepsy type, have not been successful indicators of long-term outcome. One predictor of the refractory state appears to be early response to AED therapy. Inadequate seizure control after initial treatment is a poor prognostic sign. Recent research into genetic causes of the refractory state has included investigation of the multiple drug resistance gene, and polymorphisms at drug targets. More work is needed to determine the causes and predictors of drug resistance. PMID:15309146

Optical Coherency Matrix Tomography

DTIC Science & Technology

2015-10-19

multiple DoFs, such a treatment necessitates introducing the notion of ‘classical entanglement ’10,19–25. In quantum mechanics, states associated with...corresponding concept of classical entanglement indi- cates the non-separability of the beam into uncoupled DoFs. After the initial suggestion by Spreeuw19, a...substantial body of work has accumulated in the past five years in which classical entanglement is exploited in solving long-standing problems in

Systematics of Charged Particle Production in Heavy-Ion Collisions with the PHOBOS Detector at Rhic

NASA Astrophysics Data System (ADS)

Steinberg, Peter A.; Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Corbo, J.; Decowski, M. P.; Garcia, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Henderson, C.; Hicks, D.; Hofman, D.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A.; Mülmenstädt, J.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Rafelski, M.; Rbeiz, M.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

2002-03-01

The multiplicity of charged particles produced in Au+Au collisions as a function of energy, centrality, rapidity and azimuthal angle has been measured with the PHOBOS detector at RHIC. These results contribute to our understanding of the initial state of heavy ion collisions and provide a means to compare basic features of particle production in nuclear collisions with more elementary systems.

Systems thinking: what business modeling can do for public health.

PubMed

Williams, Warren; Lyalin, David; Wingo, Phyllis A

2005-01-01

Today's public health programs are complex business systems with multiple levels of collaborating federal, state, and local entities. The use of proven systems engineering modeling techniques to analyze, align, and streamline public health operations is in the beginning stages. The authors review the initial business modeling efforts in immunization and cancer registries and present a case to broadly apply business modeling approaches to analyze and improve public health processes.

Examining Differentiation and Utilization of iPads across Content Areas in an Independent, PreK-4th Grade Elementary School

ERIC Educational Resources Information Center

Milman, Natalie B.; Carlson-Bancroft, Angela; Vanden Boogart, Amy

2014-01-01

This mixed methods case study examined the implementation of a 1:1 iPad initiative in a suburban, co-educational, independent, preK-4th grade elementary school in the United States. This article focuses on how teachers used iPads to differentiate instruction and across multiple content areas. Findings show the processes by which teachers employed…

Generalized Grover's Algorithm for Multiple Phase Inversion States

NASA Astrophysics Data System (ADS)

Byrnes, Tim; Forster, Gary; Tessler, Louis

2018-02-01

Grover's algorithm is a quantum search algorithm that proceeds by repeated applications of the Grover operator and the Oracle until the state evolves to one of the target states. In the standard version of the algorithm, the Grover operator inverts the sign on only one state. Here we provide an exact solution to the problem of performing Grover's search where the Grover operator inverts the sign on N states. We show the underlying structure in terms of the eigenspectrum of the generalized Hamiltonian, and derive an appropriate initial state to perform the Grover evolution. This allows us to use the quantum phase estimation algorithm to solve the search problem in this generalized case, completely bypassing the Grover algorithm altogether. We obtain a time complexity of this case of √{D /Mα }, where D is the search space dimension, M is the number of target states, and α ≈1 , which is close to the optimal scaling.

Multiple recurrent ischaemic strokes in a patient with cancer: is there a role for the initiation of anticoagulation therapy for secondary stroke prevention?

PubMed

Suero-Abreu, Giselle Alexandra; Cheng, Jia Zhen; Then, Ryna Karina

2017-06-03

A 52-year-old woman with a medical history of cervical and thyroid cancer, hypertension, dyslipidaemia, uncontrolled diabetes and heavy smoking was diagnosed with a new metastatic cholangiocarcinoma. While undergoing palliative chemotherapy, she developed dysarthria and left-sided weakness. Imaging studies showed multiple bilateral ischaemic strokes. On hospital days 2 and 5, she developed worsening neurological symptoms and imaging studies revealed new areas of ischaemia on respective days. Subsequent workup did not revealed a clear aetiology for the multiple ischaemic events and hypercoagulability studies were only significant for a mildly elevated serum D-dimer level. Although guidelines are unclear, full-dose anticoagulation with low molecular weight heparin was initiated given her high risk of stroke recurrence. She was discharged to acute rehabilitation but, within a month, she experienced complications of her malignant disease progression and a new pulmonary thromboembolism. The patient died soon after being discharged home with hospice care. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Enhanced sampling by multiple molecular dynamics trajectories: carbonmonoxy myoglobin 10 micros A0-->A(1-3) transition from ten 400 picosecond simulations.

PubMed

Loccisano, Anne E; Acevedo, Orlando; DeChancie, Jason; Schulze, Brita G; Evanseck, Jeffrey D

2004-05-01

The utility of multiple trajectories to extend the time scale of molecular dynamics simulations is reported for the spectroscopic A-states of carbonmonoxy myoglobin (MbCO). Experimentally, the A0-->A(1-3) transition has been observed to be 10 micros at 300 K, which is beyond the time scale of standard molecular dynamics simulations. To simulate this transition, 10 short (400 ps) and two longer time (1.2 ns) molecular dynamics trajectories, starting from five different crystallographic and solution phase structures with random initial velocities centered in a 37 A radius sphere of water, have been used to sample the native-fold of MbCO. Analysis of the ensemble of structures gathered over the cumulative 5.6 ns reveals two biomolecular motions involving the side chains of His64 and Arg45 to explain the spectroscopic states of MbCO. The 10 micros A0-->A(1-3) transition involves the motion of His64, where distance between His64 and CO is found to vary up to 8.8 +/- 1.0 A during the transition of His64 from the ligand (A(1-3)) to bulk solvent (A0). The His64 motion occurs within a single trajectory only once, however the multiple trajectories populate the spectroscopic A-states fully. Consequently, multiple independent molecular dynamics simulations have been found to extend biomolecular motion from 5 ns of total simulation to experimental phenomena on the microsecond time scale.

Enabling Highly Effective Boiling from Superhydrophobic Surfaces

NASA Astrophysics Data System (ADS)

Allred, Taylor P.; Weibel, Justin A.; Garimella, Suresh V.

2018-04-01

A variety of industrial applications such as power generation, water distillation, and high-density cooling rely on heat transfer processes involving boiling. Enhancements to the boiling process can improve the energy efficiency and performance across multiple industries. Highly wetting textured surfaces have shown promise in boiling applications since capillary wicking increases the maximum heat flux that can be dissipated. Conversely, highly nonwetting textured (superhydrophobic) surfaces have been largely dismissed for these applications as they have been shown to promote formation of an insulating vapor film that greatly diminishes heat transfer efficiency. The current Letter shows that boiling from a superhydrophobic surface in an initial Wenzel state, in which the surface texture is infiltrated with liquid, results in remarkably low surface superheat with nucleate boiling sustained up to a critical heat flux typical of hydrophilic wetting surfaces, and thus upends this conventional wisdom. Two distinct boiling behaviors are demonstrated on both micro- and nanostructured superhydrophobic surfaces based on the initial wetting state. For an initial surface condition in which vapor occupies the interstices of the surface texture (Cassie-Baxter state), premature film boiling occurs, as has been commonly observed in the literature. However, if the surface texture is infiltrated with liquid (Wenzel state) prior to boiling, drastically improved thermal performance is observed; in this wetting state, the three-phase contact line is pinned during vapor bubble growth, which prevents the development of a vapor film over the surface and maintains efficient nucleate boiling behavior.

Single-Molecule Probing the Energy Landscape of Enzymatic Reaction and Non-Covalent Interactions

NASA Astrophysics Data System (ADS)

Lu, H. Peter; Hu, Dehong; Chen, Yu; Vorpagel, Erich R.

2002-03-01

We have applied single-molecule spectroscopy under physiological conditions to study the mechanisms and dynamics of T4 lysozyme enzymatic reactions, characterizing mode-specific protein conformational dynamics. Enzymatic reaction turnovers and the associated structure changes of individual protein molecules were observed simultaneously in real-time. The overall reaction rates were found to vary widely from molecule-to-molecule, and the initial non-specific binding of the enzyme to the substrate was seen to dominate this inhomogeneity. The reaction steps subsequent to the initial binding were found to have homogeneous rates. Molecular dynamics simulation has been applied to elucidate the mechanism and intermediate states of the single-molecule enzymatic reaction. Combining the analysis of single-molecule experimental trajectories, MD simulation trajectories, and statistical modeling, we have revealed the nature of multiple intermediate states involved in the active enzyme-substrate complex formation and the associated conformational change mechanism and dynamics.

Recovery methods of the dragonfly from irregular initial conditions

NASA Astrophysics Data System (ADS)

Melfi, James; Leonardo, Anthony; Wang, Jane

We release dragonflies from a magnetic tether in a wide range of initial orientations, which results in them utilizing multiple methods to regain their typical flight orientation. Special focus is placed on dropping them while upside down, as the recovery method used is a purely rolling motion. Filming this stereotypical motion with a trio of high speed cameras at 4000 fps, we capture detailed body and wing kinematics data to determine how the dragonfly generates this motion. By replaying the flights within a computer simulation, we can isolate the significant changes to wing kinematics, and find that it is an asymmetry in the wing pitch which generates the roll. Further investigation demonstrates that this choice is highly dependent upon the state of the dragonfly, and as such our results indicate the dragonfly both tracks its current state, and changes its mid-flight control mechanisms accordingly.

Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance

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

Kilic, C.; Raible, C. C.; Stocker, T. F., E-mail: stocker@climate.unibe.ch

Stable, steady climate states on an Earth-size planet with no continents are determined as a function of the tilt of the planet’s rotation axis (obliquity) and stellar irradiance. Using a general circulation model of the atmosphere coupled to a slab ocean and a thermodynamic sea ice model, two states, the Aquaplanet and the Cryoplanet, are found for high and low stellar irradiance, respectively. In addition, four stable states with seasonally and perennially open water are discovered if comprehensively exploring a parameter space of obliquity from 0° to 90° and stellar irradiance from 70% to 135% of the present-day solar constant.more » Within 11% of today’s solar irradiance, we find a rich structure of stable states that extends the area of habitability considerably. For the same set of parameters, different stable states result if simulations are initialized from an aquaplanet or a cryoplanet state. This demonstrates the possibility of multiple equilibria, hysteresis, and potentially rapid climate change in response to small changes in the orbital parameters. The dynamics of the atmosphere of an aquaplanet or a cryoplanet state is investigated for similar values of obliquity and stellar irradiance. The atmospheric circulation substantially differs in the two states owing to the relative strength of the primary drivers of the meridional transport of heat and momentum. At 90° obliquity and present-day solar constant, the atmospheric dynamics of an Aquaplanet state and one with an equatorial ice cover is analyzed.« less

Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance

NASA Astrophysics Data System (ADS)

Kilic, C.; Raible, C. C.; Stocker, T. F.

2017-08-01

Stable, steady climate states on an Earth-size planet with no continents are determined as a function of the tilt of the planet’s rotation axis (obliquity) and stellar irradiance. Using a general circulation model of the atmosphere coupled to a slab ocean and a thermodynamic sea ice model, two states, the Aquaplanet and the Cryoplanet, are found for high and low stellar irradiance, respectively. In addition, four stable states with seasonally and perennially open water are discovered if comprehensively exploring a parameter space of obliquity from 0° to 90° and stellar irradiance from 70% to 135% of the present-day solar constant. Within 11% of today’s solar irradiance, we find a rich structure of stable states that extends the area of habitability considerably. For the same set of parameters, different stable states result if simulations are initialized from an aquaplanet or a cryoplanet state. This demonstrates the possibility of multiple equilibria, hysteresis, and potentially rapid climate change in response to small changes in the orbital parameters. The dynamics of the atmosphere of an aquaplanet or a cryoplanet state is investigated for similar values of obliquity and stellar irradiance. The atmospheric circulation substantially differs in the two states owing to the relative strength of the primary drivers of the meridional transport of heat and momentum. At 90° obliquity and present-day solar constant, the atmospheric dynamics of an Aquaplanet state and one with an equatorial ice cover is analyzed.

Statistical analysis of electric field parameters for negative lightning in Malaysia

NASA Astrophysics Data System (ADS)

Wooi, Chin-Leong; Abdul-Malek, Zulkurnain; Ahmad, Noor-Azlinda; El Gayar, Ali I.

2016-08-01

This paper presents a comparative study on the electric field and its derivative parameters of negative lightning in Malaysia and other regions. This study is the first in Malaysia where the parameters of negative electric field and its derivative are thoroughly analyzed. 104 negative lightning flashes containing 277 negative return strokes occurring within 10-100 km from the measuring station and recorded during monsoon period in the state of Johor, Malaysia had been analyzed. It was found that 73% of the recorded flashes are multiple strokes with an average multiplicity of 2.6 strokes per flash. For first return strokes, the arithmetic mean (AM) of initial peak electric field and the AM of initial peak electric field derivative are 21.8 V/m and 11.3 V/m/μs, respectively. The initial peaks of electric field and its derivative for first return strokes are larger than those for the subsequent return strokes. Comparison of overall results with those obtained earlier in Sri Lanka, Germany, Sweden, Japan, Florida indicates that several electric field and its derivative parameters are affected by propagation media and geographical region. Similarity of results with other countries having the same climatic condition is also observed.

Correlating Polymer Crystals via Self-Induced Nucleation

NASA Astrophysics Data System (ADS)

Reiter, Günter

Crystallizable polymers often form multiple stacks of uniquely oriented lamellae, which have good registry despite being separated by amorphous fold surfaces. These correlations require multiple synchronized, yet unidentified, nucleation events. Here, we demonstrate that in thin films of isotactic polystyrene, the probability of generating correlated lamellae is controlled by the branched morphology of a single primary lamella. The nucleation density ns of secondary lamellae is found to be dependent on the width of the branches of the primary lamella. This relation is independent of molecular weight, crystallization temperature, and film thickness. We propose a nucleation mechanism based on the insertion of polymers into a branched primary lamellar crystal. Even in single crystals, characterized by faceted structures with a well-defined envelope reflecting the underlying crystal unit cell, polymers are folded and thus in a meta-stable state. Annealing such meta-stable single crystals allowed to unveil the initial morphological framework of a dendritic single crystal, i.e. the initial stages of growth.

Reducing Traumatic Brain Injuries in Youth Sports: Youth Sports Traumatic Brain Injury State Laws, January 2009–December 2012

PubMed Central

2013-01-01

Objectives. I sought to describe current state-wide youth sports traumatic brain injury (TBI) laws and their relationship to prevailing scientific understandings of youth sports TBIs, and to facilitate further research by creating an open-source data set of current laws. Methods. I used Westlaw and LexisNexis databases to create a 50-state data set of youth sports TBI laws enacted between January 2009 and December 2012. I collected and coded the text and citations of each law and developed a protocol and codebook to facilitate future research. Results. Forty-four states and Washington, DC, passed youth sports TBI laws between 2009 and 2012. No state’s youth sports TBI law focuses on primary prevention. Instead, such laws focus on (1) increasing coaches’ and parents’ ability to identify and respond to TBIs and (2) reducing the immediate risk of multiple TBIs. Conclusions. Existing youth sports TBI laws were not designed to reduce initial TBIs. Evaluation is required to assess their effectiveness in reducing the risk and consequences of multiple TBIs. Continued research and evaluation of existing laws will be needed to develop a more comprehensive youth TBI-reduction solution. PMID:23678903

Nonadiabatic excited-state molecular dynamics: modeling photophysics in organic conjugated materials.

PubMed

Nelson, Tammie; Fernandez-Alberti, Sebastian; Roitberg, Adrian E; Tretiak, Sergei

2014-04-15

To design functional photoactive materials for a variety of technological applications, researchers need to understand their electronic properties in detail and have ways to control their photoinduced pathways. When excited by photons of light, organic conjugated materials (OCMs) show dynamics that are often characterized by large nonadiabatic (NA) couplings between multiple excited states through a breakdown of the Born-Oppenheimer (BO) approximation. Following photoexcitation, various nonradiative intraband relaxation pathways can lead to a number of complex processes. Therefore, computational simulation of nonadiabatic molecular dynamics is an indispensable tool for understanding complex photoinduced processes such as internal conversion, energy transfer, charge separation, and spatial localization of excitons. Over the years, we have developed a nonadiabatic excited-state molecular dynamics (NA-ESMD) framework that efficiently and accurately describes photoinduced phenomena in extended conjugated molecular systems. We use the fewest-switches surface hopping (FSSH) algorithm to treat quantum transitions among multiple adiabatic excited state potential energy surfaces (PESs). Extended molecular systems often contain hundreds of atoms and involve large densities of excited states that participate in the photoinduced dynamics. We can achieve an accurate description of the multiple excited states using the configuration interaction single (CIS) formalism with a semiempirical model Hamiltonian. Analytical techniques allow the trajectory to be propagated "on the fly" using the complete set of NA coupling terms and remove computational bottlenecks in the evaluation of excited-state gradients and NA couplings. Furthermore, the use of state-specific gradients for propagation of nuclei on the native excited-state PES eliminates the need for simplifications such as the classical path approximation (CPA), which only uses ground-state gradients. Thus, the NA-ESMD methodology offers a computationally tractable route for simulating hundreds of atoms on ~10 ps time scales where multiple coupled excited states are involved. In this Account, we review recent developments in the NA-ESMD modeling of photoinduced dynamics in extended conjugated molecules involving multiple coupled electronic states. We have successfully applied the outlined NA-ESMD framework to study ultrafast conformational planarization in polyfluorenes where the rate of torsional relaxation can be controlled based on the initial excitation. With the addition of the state reassignment algorithm to identify instances of unavoided crossings between noninteracting PESs, NA-ESMD can now be used to study systems in which these so-called trivial unavoided crossings are expected to predominate. We employ this technique to analyze the energy transfer between poly(phenylene vinylene) (PPV) segments where conformational fluctuations give rise to numerous instances of unavoided crossings leading to multiple pathways and complex energy transfer dynamics that cannot be described using a simple Förster model. In addition, we have investigated the mechanism of ultrafast unidirectional energy transfer in dendrimers composed of poly(phenylene ethynylene) (PPE) chromophores and have demonstrated that differential nuclear motion favors downhill energy transfer in dendrimers. The use of native excited-state gradients allows us to observe this feature.

Cooperative angle-only orbit initialization via fusion of admissible areas

NASA Astrophysics Data System (ADS)

Jia, Bin; Pham, Khanh; Blasch, Erik; Chen, Genshe; Shen, Dan; Wang, Zhonghai

2017-05-01

For the short-arc angle only orbit initialization problem, the admissible area is often used. However, the accuracy using a single sensor is often limited. For high value space objects, it is desired to achieve more accurate results. Fortunately, multiple sensors, which are dedicated to space situational awareness, are available. The work in this paper uses multiple sensors' information to cooperatively initialize the orbit based on the fusion of multiple admissible areas. Both the centralized fusion and decentralized fusion are discussed. Simulation results verify the expectation that the orbit initialization accuracy is improved by using information from multiple sensors.

Multiple parent bodies of ordinary chondrites

NASA Technical Reports Server (NTRS)

Yomogida, K.; Matsui, T.

1984-01-01

Thermal histories of chondrite parent bodies are calculated from an initial state with material in a powder-like form, taking into account the effect of consolidation state on thermal conductivity. The very low thermal conductivity of the starting materials makes it possible for a small body with a radius of less than 100 km to be heated by several hundred degrees even if long-lived radioactive elements in chondritic abundances are the only source of heat. The maximum temperature is determined primarily by the temperature at which sintering of the constituent materials occurs. The thermal state of the interior of a chondrite parent body after sintering has begun is nearly isothermal. Near the surface, however, where the material is unconsolidated and the thermal conductivity is much lower, the thermal gradient is quite large. This result contradicts the conventional 'onion-shell' model of chondrite parent bodies. But because the internal temperature is almost constant through the whole body, it supports a 'multiple-parent bodies' model, according to which each petrologic type of chondrite comes from a different parent body.

Mechanisms for Differential Protein Production in Toxin–Antitoxin Systems

PubMed Central

Deter, Heather S.; Jensen, Roderick V.; Mather, William H.; Butzin, Nicholas C.

2017-01-01

Toxin–antitoxin (TA) systems are key regulators of bacterial persistence, a multidrug-tolerant state found in bacterial species that is a major contributing factor to the growing human health crisis of antibiotic resistance. Type II TA systems consist of two proteins, a toxin and an antitoxin; the toxin is neutralized when they form a complex. The ratio of antitoxin to toxin is significantly greater than 1.0 in the susceptible population (non-persister state), but this ratio is expected to become smaller during persistence. Analysis of multiple datasets (RNA-seq, ribosome profiling) and results from translation initiation rate calculators reveal multiple mechanisms that ensure a high antitoxin-to-toxin ratio in the non-persister state. The regulation mechanisms include both translational and transcriptional regulation. We classified E. coli type II TA systems into four distinct classes based on the mechanism of differential protein production between toxin and antitoxin. We find that the most common regulation mechanism is translational regulation. This classification scheme further refines our understanding of one of the fundamental mechanisms underlying bacterial persistence, especially regarding maintenance of the antitoxin-to-toxin ratio. PMID:28677629

Resistive MHD modelling of the quasi-single helicity state in the KTX regimes

NASA Astrophysics Data System (ADS)

Luo, Bing; Zhu, Ping; Li, Hong; Liu, Wandong; KTX Team

2018-01-01

The potential formation of a quasi-single-helicity (QSH) state in the Keda Torus eXperiment (KTX) is investigated in resistive MHD simulations using the NIMROD code. We focus on the effects of finite resistivity on the mode structure and characteristics of the dominant linear and nonlinear resistive tearing-mode in a finite β, cylindrical configuration of a reversed field pinch model for KTX. In the typical resistive regimes of KTX where the Lundquist number S=5 × 104 , the plasma transitions to a steady QSH state after evolving through an initial transient phase with multiple helicities. The dominant mode of the QSH state develops from the dominant linear tearing mode instability. In the lower β regime, the QSH state is intermittent and short in duration; in the higher β regime, the QSH state persists for a longer time and should be more easily observed in experiments.

How Maryland increased infection prevention and control activity in long-term care facilities, 2003-2008.

PubMed

Roup, Brenda J; Scaletta, Joseph M

2011-05-01

In January 2003, the Maryland Department of Health and Mental Hygiene (DHMH) assessed the state of infection prevention and control (IPC) resources and practices in all long-term care facilities (LTC) in the state. Only 8.1% of facilities that responded employed a trained IPC professional (IP) who managed the facility IPC program. Between 2003 and 2008, the DHMH partnered with long-term care industry trade associations and spearheaded regulatory, educational, and financial initiatives to improve this situation. In January 2008, all LTC facilities in the state were resurveyed to determine the impact of these initiatives on IPC activities. The 2008 survey indicated that 44% of LTC facilities used a trained IP who managed the IPC program, a 5-fold increase from 2003. Unpublished DHMH outbreak data indicated that LTC facilities with a trained IP recognized and reported outbreaks to the local health department 2 days sooner than facilities without a trained IP, resulting in fewer cases of disease. Multiple initiatives with concerned stakeholders and LTC partners over the course of 5 years resulted in increased numbers of LTC facilities with trained IPs who recognized and responded to outbreaks sooner than facilities without trained IPs. Copyright © 2011 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Use of the 2010 McDonald criteria can facilitate early diagnosis of pediatric multiple sclerosis in a predominantly black cohort.

PubMed

Williams, Mitchel T; Tapos, Daniela O; Juhász, Csaba

2014-12-01

Pediatric-onset multiple sclerosis represents around 3-5% of all patients with multiple sclerosis. Both the 2005 and 2010 McDonald criteria for multiple sclerosis have been suggested for the possible use in pediatric-onset multiple sclerosis. Modifications incorporated into the 2010 criteria enabled the fulfillment of dissemination in time to be met with the initial magnetic resonance imaging. The present study was designed to compare the diagnostic sensitivity of these criteria at initial presentation, the time to fulfilling them, and secondary effects of ethnicity in pediatric-onset multiple sclerosis. Twenty-five children with clinically definite multiple sclerosis (mean age, 14.6 ± 3.1 years; 15 girls) from a single center between 2005 and 2012 were analyzed using both the 2005 and 2010 McDonald criteria based on initial clinical presentation and neuroimaging findings comparing diagnostic sensitivity, time interval to meet diagnosis, and ethnicity. Initial multiple sclerosis diagnosis rates applying the 2005 McDonald criteria were 32% compared with 92% for the 2010 criteria (P = 0.0003). The mean time after initial signs until the 2005 and 2010 McDonald criteria for multiple sclerosis were met was 5.0 vs 0.7 months, respectively (P = 0.001). Time to diagnosis using the 2010 criteria was shorter in black children than the European white (P = 0.005). The 2010 McDonald criteria are an appropriate tool for the timely diagnosis of pediatric multiple sclerosis, especially in black children, potentially allowing an earlier initiation of disease-modifying therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

Body-force-driven multiplicity and stability of combined free and forced convection in rotating curved ducts: Coriolis force

NASA Astrophysics Data System (ADS)

Yang, T.; Wang, L.

A numerical study is made on the fully developed bifurcation structure and stability of forced convection in a rotating curved duct of square cross-section. Solution structure is determined as variation of a parameter that indicates the effect of rotation (Coriolis-force-driven multiplicity). Three solutions for the flows in a stationary curved duct obtained in the work of Yang and Wang [1] are used as initial solutions of continuation calculations to unfold the solution branches. Twenty-one solution branches are found comparing with five obtained by Selmi and Nandakumar [2]. Dynamic responses of the multiple solutions to finite random disturbances are examined by the direct transient computation. Results show that characteristics of physically realizable fully developed flows changes significantly with variation of effect of rotation. Fourteen sub-ranges are identified according to characteristics of physically realizable solutions. As rotation effect changes, possible physically realizable fully-developed flows can be stable steady 2-cell state, stable multi-cell state, temporal periodic oscillation between symmetric/asymmetric 2-cell/4-cell flows, temporal oscillation with intermittency, temporal chaotic oscillation and temporal oscillation with pseudo intermittency. Among these possible physically realizable fully developed flows, stable multi-cell state and stable steady 2-cell state exist as dual stable. And oscillation with pseudo intermittency is a new phenomenon. In addition to the temporal oscillation with intermittency, sudden shift from stationary stable solution to temporal chaotic oscillation is identified to be another way of onset of chaos.

Resonant recombination and autoionization in electron-ion collisions

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

Mueller, A.

1990-06-01

The occurence of resonances in elastic and inelastic electron-ion collisions is discussed. Resonant processes involve excitation of the ion with simultaneous capture of the initially free electron. The decay mechanism subsequent to the formation of the intermediate multiply excited state determines whether a resonance is found in recombination, excitation, elastic scattering, in single or even in multiple ionization. This review concentrates on resonances in the ionization channel. Correlated two-electron transitions are considered.

"FORCE" learning in recurrent neural networks as data assimilation

NASA Astrophysics Data System (ADS)

Duane, Gregory S.

2017-12-01

It is shown that the "FORCE" algorithm for learning in arbitrarily connected networks of simple neuronal units can be cast as a Kalman Filter, with a particular state-dependent form for the background error covariances. The resulting interpretation has implications for initialization of the learning algorithm, leads to an extension to include interactions between the weight updates for different neurons, and can represent relationships within groups of multiple target output signals.

Resource utilization with insulin pump therapy for type 2 diabetes mellitus.

PubMed

Lynch, Peter M; Riedel, Aylin Altan; Samant, Navendu; Fan, Ying; Peoples, Tim; Levinson, Jennifer; Lee, Scott W

2010-01-01

To evaluate the effects of switching from multiple daily injection (MDI) therapy to insulin pump therapy, also called continuous subcutaneous insulin infusion (CSII), on antidiabetic drug and healthcare resource utilization. This study was a retrospective analysis of administrative claims data from a large geographically diverse health plan in the United States from January 1, 2005, through April 30, 2008. Changes in antidiabetic drug use, antidiabetic drug switching and augmentation, and healthcare utilization during the baseline period and after CSII initiation were assessed using paired t test. There were 3649 possible subjects, of whom 943 met the criteria for analysis. The mean number of antidiabetic drugs used decreased by 46% after CSII initiation, and the mean reduction in antidiabetic drug utilization was 0.67; both were statistically significant. More than one-third of subjects who were taking antidiabetic drugs before CSII initiation discontinued oral therapy after CSII initiation. The number of subjects using multiple antidiabetic drugs significantly decreased after CSII initiation by 58%, and rates of switching or augmenting significantly decreased from 42% at baseline to 25% after CSII initiation.The rates of emergency department visits and inpatient admissions significantly decreased, and the rate of ambulatory visits significantly increased. CSII was associated with significant decreases in antidiabetic drug and healthcare resource utilization, contributing to stability of care. The evidence from this study indicates that CSII should be considered as an option for patients with type 2 diabetes mellitus who are using MDI and are experiencing a high degree of antidiabetic drug and healthcare resource utilization.

Gender difference in early initiation of methamphetamine use among current methamphetamine users in Muse, Northern Shan State, Myanmar.

PubMed

Saw, Yu Mon; Saw, Thu Nandar; Yasuoka, Junko; Chan, Nyein; Kham, Nang Pann Ei; Khine, Wint; Cho, Su Myat; Jimba, Masamine

2017-05-08

Globally, methamphetamine (MA) use is a significant public health concern due to unprecedented health effects of its use. However, gender similarities and differences in early age of MA initiation and its risk factors among current MA users have been understudied in a developing country setting. A community-based, cross-sectional study was conducted using a computer assisted self-interviewing program from January to March 2013 in Muse, Northern Shan State, Myanmar. A total of 1362 (775 male and 587 female) self-reported current MA users aged between 18 and 35 years were recruited using respondent-driven sampling. Two gender-stratified multiple logistic regression models (models I and II) were done for analysis. For similarities, 73.0% of males and 60.5% of females initiated MA before their 18th birthday. The early age of MA initiation was positively associated with the reasons and places of the first time MA use among both genders. For differences, males [hazard ratio 1.35; 95% confidence interval, 1.18-1.54] had a significantly higher risk than females to initiate MA at earlier age. Among male users, participants who had bisexual/homosexual preferences were more likely to initiate MA use earlier. In contrast, female users who exchanged sex for money and/or drugs were more likely to initiate MA in earlier age. More than 60.0% of male and female participants initiated MA use early; however, males initiated use earlier than females. Although similarities were found among both genders, differences found in key risk factors for early age MA initiation suggest that gender-specific, MA prevention programs are urgently needed in Myanmar.

Precision Medicine in Gastrointestinal Pathology.

PubMed

Wang, David H; Park, Jason Y

2016-05-01

-Precision medicine is the promise of individualized therapy and management of patients based on their personal biology. There are now multiple global initiatives to perform whole-genome sequencing on millions of individuals. In the United States, an early program was the Million Veteran Program, and a more recent proposal in 2015 by the president of the United States is the Precision Medicine Initiative. To implement precision medicine in routine oncology care, genetic variants present in tumors need to be matched with effective clinical therapeutics. When we focus on the current state of precision medicine for gastrointestinal malignancies, it becomes apparent that there is a mixed history of success and failure. -To present the current state of precision medicine using gastrointestinal oncology as a model. We will present currently available targeted therapeutics, promising new findings in clinical genomic oncology, remaining quality issues in genomic testing, and emerging oncology clinical trial designs. -Review of the literature including clinical genomic studies on gastrointestinal malignancies, clinical oncology trials on therapeutics targeted to molecular alterations, and emerging clinical oncology study designs. -Translating our ability to sequence thousands of genes into meaningful improvements in patient survival will be the challenge for the next decade.

Dementia: A complex disease with multiple etiologies and multiple treatments.

PubMed

Fisher, Travis J; Schwartz, Ann C; Greenspan, Heather N; Heinrich, Thomas W

As the population of the United States ages, the rates of dementia are also likely to increase. Clinicians will, therefore, likely be asked to evaluate and treat an escalating number of patients experiencing a decline in multiple domains of cognitive function, which is the hallmark of neurocognitive disorders. It is also probable that clinicians will be confronted with management dilemmas related to the myriad of psychological and behavioral problems that often occur as a consequence of the neurocognitive impairment. In fact, these behavioral and psychological issues might be the initial symptoms that lead the patient to present to the clinician. Dementia has multiple potential etiologies, and a careful diagnostic assessment is imperative to best characterize the specific type of dementia impacting the patient. This is important, as knowing the type of dementia helps the clinician choose the most effective treatment. Potential treatments should be interdisciplinary in scope, patient/family-centered, and may include both nonpharmacologic and pharmacologic treatments. © The Author(s) 2016.

First Results from the Test Of Astronomy STandards (TOAST) Assessment Instrument

NASA Astrophysics Data System (ADS)

Slater, Stephanie

2009-01-01

Considerable effort in the astronomy education research over the past several years has focused on developing assessment tools in the form of multiple-choice conceptual diagnostics and content knowledge surveys. This has been critically important in advancing astronomy as a sub-discipline of physics education research, allowing researchers to establish the initial knowledge state of students as well as to attempt to measure some of the impacts of innovative instructional interventions. Before now, few of the existing instruments were constructed upon a solid list of clearly articulated and widely agreed upon learning objectives. Moving beyond the 10-year old Astronomy Diagnostics Test, we have developed and validated a new assessment instrument that is tightly aligned to the consensus learning goals stated by the American Astronomical Society - Chair's Conference on ASTRO 101, the American Association of the Advancement of Science's Project 2061 Benchmarks, and the National Research Council's National Science Education Standards. Researchers from the Cognition in Astronomy, Physics and Earth sciences Research (CAPER) Team at the University of Wyoming's Science and Math Teaching Center (UWYO SMTC) designed a criterion-referenced assessment tool, called the Test Of Astronomy STandards (TOAST). Through iterative development, this multiple-choice instrument has a high degree of reliability and validity for instructors and researchers needing information on students’ initial knowledge state at the beginning of a course and can be used, in aggregate, to help measure the impact of course-length duration instructional strategies for undergraduate science survey courses with learning goals tightly aligned to the consensus goals of the astronomy education community.

Factors affecting initial disability allowance rates for the Disability Insurance and Supplemental Security Income programs: the role of the demographic and diagnostic composition of applicants and local labor market conditions.

PubMed

Rupp, Kalman

2012-01-01

Various factors outside the control of decision makers may affect the rate at which disability applications are allowed or denied during the initial step of eligibility determination in the Social Security Disability Insurance (DI) and Supplemental Security Income (SSI) programs. In this article, using individual-level data on applications, I estimate the role of three important factors--the demographic characteristics of applicants, the diagnostic mix of applicants, and the local unemployment rate--in affecting the probability of an initial allowance and state allowance rates. I use a random sample of initial determinations from 1993 through 2008 and a fixed-effects multiple regression framework. The empirical results show that the demographic and diagnostic characteristics of applicants and the local unemployment rate substantially affect the initial allowance rate. An increase in the local unemployment rate tends to be associated with a decrease in the initial allowance rate. This negative relationship holds for adult DI and SSI applicants and for SSI childhood applicants.

Threshold-based epidemic dynamics in systems with memory

NASA Astrophysics Data System (ADS)

Bodych, Marcin; Ganguly, Niloy; Krueger, Tyll; Mukherjee, Animesh; Siegmund-Schultze, Rainer; Sikdar, Sandipan

2016-11-01

In this article we analyze an epidemic dynamics model (SI) where we assume that there are k susceptible states, that is a node would require multiple (k) contacts before it gets infected. In specific, we provide a theoretical framework for studying diffusion rate in complete graphs and d-regular trees with extensions to dense random graphs. We observe that irrespective of the topology, the diffusion process could be divided into two distinct phases: i) the initial phase, where the diffusion process is slow, followed by ii) the residual phase where the diffusion rate increases manifold. In fact, the initial phase acts as an indicator for the total diffusion time in dense graphs. The most remarkable lesson from this investigation is that such a diffusion process could be controlled and even contained if acted upon within its initial phase.

Sub-500 fs electronically nonadiabatic chemical dynamics of energetic molecules from the S1 excited state: Ab initio multiple spawning study

NASA Astrophysics Data System (ADS)

Ghosh, Jayanta; Gajapathy, Harshad; Konar, Arindam; Narasimhaiah, Gowrav M.; Bhattacharya, Atanu

2017-11-01

Energetic materials store a large amount of chemical energy. Different ignition processes, including laser ignition and shock or compression wave, initiate the energy release process by first promoting energetic molecules to the electronically excited states. This is why a full understanding of initial steps of the chemical dynamics of energetic molecules from the excited electronic states is highly desirable. In general, conical intersection (CI), which is the crossing point of multidimensional electronic potential energy surfaces, is well established as a controlling factor in the initial steps of chemical dynamics of energetic molecules following their electronic excitations. In this article, we have presented different aspects of the ultrafast unimolecular relaxation dynamics of energetic molecules through CIs. For this task, we have employed ab initio multiple spawning (AIMS) simulation using the complete active space self-consistent field (CASSCF) electronic wavefunction and frozen Gaussian-based nuclear wavefunction. The AIMS simulation results collectively reveal that the ultrafast relaxation step of the best energetic molecules (which are known to exhibit very good detonation properties) is completed in less than 500 fs. Many, however, exhibit sub-50 fs dynamics. For example, nitro-containing molecules (including C-NO2, N-NO2, and O-NO2 active moieties) relax back to the ground state in approximately 40 fs through similar (S1/S0)CI conical intersections. The N3-based energetic molecule undergoes the N2 elimination process in 40 fs through the (S1/S0)CI conical intersection. Nitramine-Fe complexes exhibit sub-50 fs Fe-O and N-O bond dissociation through the respective (S1/S0)CI conical intersection. On the other hand, tetrazine-N-oxides, which are known to exhibit better detonation properties than tetrazines, undergo internal conversion in a 400-fs time scale, while the relaxation time of tetrazine is very long (about 100 ns). Many other characteristics of sub-500 fs nonadiabatic decay of energetic molecules are discussed. In the end, many unresolved issues associated with the ultrafast nonadiabatic chemical dynamics of energetic molecules are presented.

Uninformative Prior Multiple Target Tracking Using Evidential Particle Filters

NASA Astrophysics Data System (ADS)

Worthy, J. L., III; Holzinger, M. J.

Space situational awareness requires the ability to initialize state estimation from short measurements and the reliable association of observations to support the characterization of the space environment. The electro-optical systems used to observe space objects cannot fully characterize the state of an object given a short, unobservable sequence of measurements. Further, it is difficult to associate these short-arc measurements if many such measurements are generated through the observation of a cluster of satellites, debris from a satellite break-up, or from spurious detections of an object. An optimization based, probabilistic short-arc observation association approach coupled with a Dempster-Shafer based evidential particle filter in a multiple target tracking framework is developed and proposed to address these problems. The optimization based approach is shown in literature to be computationally efficient and can produce probabilities of association, state estimates, and covariances while accounting for systemic errors. Rigorous application of Dempster-Shafer theory is shown to be effective at enabling ignorance to be properly accounted for in estimation by augmenting probability with belief and plausibility. The proposed multiple hypothesis framework will use a non-exclusive hypothesis formulation of Dempster-Shafer theory to assign belief mass to candidate association pairs and generate tracks based on the belief to plausibility ratio. The proposed algorithm is demonstrated using simulated observations of a GEO satellite breakup scenario.

Subunit III-depleted cytochrome c oxidase provides insight into the process of proton uptake by proteins

PubMed Central

Varanasi, Lakshman; Hosler, Jonathan P.

2011-01-01

We review studies of subunit III-depleted cytochrome c oxidase (CcO III (−)) that elucidate the structural basis of steady-state proton uptake from solvent into an internal proton transfer pathway. The removal of subunit III from R. sphaeroides CcO makes proton uptake into the D pathway a rate-determining step, such that measurements of the pH dependence of steady-state O2 consumption can be used to compare the rate and functional pKa of proton uptake by D pathways containing different initial proton acceptors. The removal of subunit III also promotes spontaneous suicide inactivation by CcO, greatly shortening its catalytic lifespan. Because the probability of suicide inactivation is controlled by the rate at which the D pathway delivers protons to the active site, measurements of catalytic lifespan provide a second method to compare the relative efficacy of proton uptake by engineered CcO III (−) forms. These simple experimental systems have been used to explore general questions of proton uptake by proteins, such as the functional value of an initial proton acceptor, whether an initial acceptor must be surface-exposed, which side chains will function as initial proton acceptors and whether multiple acceptors can speed proton uptake. PMID:22023935

H{sub 2} dissociation due to collisions with He

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

Ohlinger, L.; Forrey, R. C.; Lee, Teck-Ghee

2007-10-15

Cross sections for dissociation of H{sub 2} due to collision with He are calculated for highly excited rovibrational states using the quantum-mechanical coupled-states approximation. An L{sup 2} Sturmian basis set with multiple length scales is used to provide a discrete representation of the H{sub 2} continuum which includes orbiting resonances and a nonresonant background. Cross sections are given over a range of translational energies for both resonant and nonresonant dissociation together with the most important bound-state transitions for many different initial states. The results demonstrate that it is possible to compute converged quantum-mechanical cross sections using basis sets of modestmore » size. It is found that collision-induced dissociation competes with inelastic scattering as a depopulation mechanism for the highly excited states. The relevance of the present calculations to astrophysical models is discussed.« less

Resistive MHD Simulation of Quasi-Single-Helicity State on KTX

NASA Astrophysics Data System (ADS)

Luo, Bing; Zhu, Ping; Li, Hong; Liu, Wandong

2016-10-01

The potential formation of quasi-single-helicity (QSH) state on Keda Torus eXperiment (KTX) is evaluated in resistive MHD simulations using the NIMROD code. In this work, we focus on the effects of finite resistivity on the mode structure and characteristics of the dominant linear and nonlinear resistive tearing-mode instability in a finite β, cylindrical reversed field pinch model configuration for KTX. In the typical resistivity regimes of KTX where Lundquist number S =105 , the plasma reaches a steady QSH state after the initial transient phase of multiple helicities. The dominat mode of the QSH state is developed from the dominat linear tearing mode instability. The conditions for and the variations of the formation of QSH states in different resistivity regimes of KTX will be reported and discussed. Supported by National Magnetic Confinement Fusion Science Program of China Grant Nos. 2014GB124002, 2015GB101004, 2011GB106000, and 2011GB106003.

Multiple-output support vector machine regression with feature selection for arousal/valence space emotion assessment.

PubMed

Torres-Valencia, Cristian A; Álvarez, Mauricio A; Orozco-Gutiérrez, Alvaro A

2014-01-01

Human emotion recognition (HER) allows the assessment of an affective state of a subject. Until recently, such emotional states were described in terms of discrete emotions, like happiness or contempt. In order to cover a high range of emotions, researchers in the field have introduced different dimensional spaces for emotion description that allow the characterization of affective states in terms of several variables or dimensions that measure distinct aspects of the emotion. One of the most common of such dimensional spaces is the bidimensional Arousal/Valence space. To the best of our knowledge, all HER systems so far have modelled independently, the dimensions in these dimensional spaces. In this paper, we study the effect of modelling the output dimensions simultaneously and show experimentally the advantages in modeling them in this way. We consider a multimodal approach by including features from the Electroencephalogram and a few physiological signals. For modelling the multiple outputs, we employ a multiple output regressor based on support vector machines. We also include an stage of feature selection that is developed within an embedded approach known as Recursive Feature Elimination (RFE), proposed initially for SVM. The results show that several features can be eliminated using the multiple output support vector regressor with RFE without affecting the performance of the regressor. From the analysis of the features selected in smaller subsets via RFE, it can be observed that the signals that are more informative into the arousal and valence space discrimination are the EEG, Electrooculogram/Electromiogram (EOG/EMG) and the Galvanic Skin Response (GSR).

Syringe Pump Performance Maintained with IV Filter Use During Low Flow Rate Delivery for Pediatric Patients.

PubMed

Chau, Destiny F; Vasilopoulos, Terrie; Schoepf, Miriam; Zhang, Christina; Fahy, Brenda G

2016-09-01

Complex surgical and critically ill pediatric patients rely on syringe infusion pumps for precise delivery of IV medications. Low flow rates and in-line IV filter use may affect drug delivery. To determine the effects of an in-line filter to remove air and/or contaminants on syringe pump performance at low flow rates, we compared the measured rates with the programmed flow rates with and without in-line IV filters. Standardized IV infusion assemblies with and without IV filters (filter and control groups) attached to a 10-mL syringe were primed and then loaded onto a syringe pump and connected to a 16-gauge, 16-cm single-lumen catheter. The catheter was suspended in a normal saline fluid column to simulate the back pressure from central venous circulation. The delivered infusate was measured by gravimetric methods at predetermined time intervals, and flow rate was calculated. Experimental trials for initial programmed rates of 1.0, 0.8, 0.6, and 0.4 mL/h were performed in control and filter groups. For each trial, the flow rate was changed to double the initial flow rate and was then returned to the initial flow rate to analyze pump performance for titration of rates often required during medication administration. These conditions (initial rate, doubling of initial rate, and return to initial rate) were analyzed separately for steady-state flow rate and time to steady state, whereas their average was used for percent deviation analysis. Differences between control and filter groups were assessed using Student t tests with adjustment for multiplicity (using n = 3 replications per group). Mean time from 0 to initial flow (startup delay) was <1 minute in both groups with no statistical difference between groups (P = 1.0). The average time to reach steady-state flow after infusion startup or rate changes was not statistically different between the groups (range, 0.8-5.5 minutes), for any flow rate or part of the trial (initial rate, doubling of initial rate, and return to initial rate), although the study was underpowered to detect small time differences. Overall, the mean steady-state flow rate for each trial was below the programmed flow rate with negative mean percent deviations for each trial. In the 1.0-mL/h initial rate trial, the steady-state flow rate attained was lower in the filter than the control group for the initial rate (P = 0.04) and doubling of initial rate (P = 0.04) with a trend during the return to initial rate (P = 0.06), although this same effect was not observed when doubling the initial rate trials of 0.8 or 0.6 mL/h or any other rate trials compared with the control group. With low flow rates used in complex surgical and pediatric critically ill patients, the addition of IV filters did not confer statistically significant changes in startup delay, flow variability, or time to reach steady-state flow of medications administered by syringe infusion pumps. The overall flow rate was lower than programmed flow rate with or without a filter.

Impact of multiple-dose versus single-dose inhaler devices on COPD patients’ persistence with long-acting β2-agonists: a dispensing database analysis

PubMed Central

van Boven, Job FM; van Raaij, Joost J; van der Galiën, Ruben; Postma, Maarten J; van der Molen, Thys; Dekhuijzen, PN Richard; Vegter, Stefan

2014-01-01

Background: With a growing availability of different devices and types of medication, additional evidence is required to assist clinicians in prescribing the optimal medication in relation to chronic obstructive pulmonary disease (COPD) patients’ persistence with long-acting β2-agonists (LABAs). Aims: To assess the impact of the type of inhaler device (multiple-dose versus single-dose inhalers) on 1-year persistence and switching patterns with LABAs. Methods: A retrospective observational cohort study was performed comparing a cohort of patients initiating multiple-dose inhalers and a cohort initiating single-dose inhalers. The study population consisted of long-acting bronchodilator naive COPD patients, initiating inhalation therapy with mono-LABAs (formoterol, indacaterol or salmeterol). Analyses were performed using pharmacy dispensing data from 1994 to 2012, obtained from the IADB.nl database. Study outcomes were 1-year persistence and switching patterns. Results were adjusted for initial prescriber, initial medication, dosing regimen and relevant comorbidities. Results: In all, 575 patients initiating LABAs were included in the final study cohort. Among them, 475 (83%) initiated a multiple-dose inhaler and 100 (17%) a single-dose inhaler. Further, 269 (47%) initiated formoterol, 9 (2%) indacaterol and 297 (52%) salmeterol. There was no significant difference in persistence between users of multiple-dose or single-dose inhalers (hazard ratio: 0.98, 95% confidence interval: 0.76–1.26, P=0.99). Over 80% re-started or switched medication. Conclusions: There seems no impact of inhaler device (multiple-dose versus single-dose inhalers) on COPD patients’ persistence with LABAs. Over 80% of patients who initially seemed to discontinue LABAs, re-started their initial medication or switched inhalers or medication within 1 year. PMID:25274453

The Impacts of State Health Reform Initiatives on Adults in New York and Massachusetts

PubMed Central

Long, Sharon K; Stockley, Karen

2011-01-01

Objective To analyze the effects of health reform efforts in two large states—New York and Massachusetts. Data Sources/Study Setting National Health Interview Survey (NHIS) data from 1999 to 2008. Study Design We take advantage of the “natural experiments” that occurred in New York and Massachusetts to compare health insurance coverage and health care access and use for adults before and after the implementation of the health policy changes. To control for underlying trends not related to the reform initiatives, we subtract changes in the outcomes over the same time period for comparison groups of adults who were not affected by the policy changes using a differences-in-differences framework. The analyses are conducted using multiple comparison groups and different time periods as a check on the robustness of the findings. Data Collection/Extraction Methods Nonelderly adults ages 19–64 in the NHIS. Principal Findings We find evidence of the success of the initiatives in New York and Massachusetts at expanding insurance coverage, with the greatest gains reported by the initiative that was broadest in scope—the Massachusetts push toward universal coverage. There is no evidence of improvements in access to care in New York, reflecting the small gains in coverage under that state's reform effort and the narrow focus of the initiative. In contrast, there were significant gains in access to care in Massachusetts, where the impact on insurance coverage was greater and a more comprehensive set of reforms were implemented to improve access to a full array of health care services. The estimated gains in coverage and access to care reported here for Massachusetts were achieved in the early period under health reform, before the state's reform initiative was fully implemented. Conclusions Comprehensive reform initiatives are more successful at addressing gaps in coverage and access to care than are narrower efforts, highlighting the potential gains under national health reform. Tracking the implications of national health reform will be challenging, as sample sizes and content in existing national surveys are not currently sufficient for in-depth evaluations of the impacts of reform within many states. PMID:21091471

Single and multiple ionization of C60 fullerenes and collective effects in collisions with highly charged C, F, and Si ions with energy 3 MeV/u

NASA Astrophysics Data System (ADS)

Kelkar, A. H.; Kadhane, U.; Misra, D.; Gulyas, L.; Tribedi, L. C.

2010-10-01

We have measured absolute cross sections for single, double, triple, and quadruple ionization of C60 in collisions with 3 MeV/u C, F, and Si projectile ions at various projectile charge states. The experiment was performed using the recoil-ion time-of-flight technique. Projectile charge state dependence of the ionization yields was compared mainly with a model based on the giant dipole plasmon resonance (GDPR). In some cases, the continuum-distorted-wave-eikonal-initial-state (CDW-EIS) model which is normally applied for ion-atom collisions was also used as a reference. An excellent qualitative agreement between the experimental data for single and double ionization and the GDPR model predictions was found for all projectile charge states.

Mosaicked Historic Airborne Imagery from Seward Peninsula, Alaska, Starting in the 1950's

DOE Data Explorer

Cherry, Jessica; Wirth, Lisa

2016-12-06

Historical airborne imagery for each Seward Peninsula NGEE Arctic site - Teller, Kougarok, Council - with multiple years for each site. This dataset includes mosaicked, geolocated and, where possible, orthorectified, historic airborne and recent satellite imagery. The older photos were sourced from USGS's Earth Explorer site and the newer, satellite imagery is from the Statewide Digital Mapping Initiative (SDMI) project managed by the Geographic Information Network of Alaska on behalf of the state of Alaska.

Comparing State-Space Multivariable Controls to Multi-SISO Controls for Load Reduction of Drivetrain-Coupled Modes on Wind Turbines through Field-Testing: Preprint

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

Fleming, P. A.; van Wingerden, J. W.; Wright, A. D.

2011-12-01

This paper presents the structure of an ongoing controller comparison experiment at NREL's National Wind Technology Center; the design process for the two controllers compared in this phase of the experiment, and initial comparison results obtained in field-testing. The intention of the study is to demonstrate the advantage of using modern multivariable methods for designing control systems for wind turbines versus conventional approaches. We will demonstrate the advantages through field-test results from experimental turbines located at the NWTC. At least two controllers are being developed side-by-side to meet an incrementally increasing number of turbine load-reduction objectives. The first, a multiplemore » single-input, single-output (m-SISO) approach, uses separately developed decoupled and classicially tuned controllers, which is, to the best of our knowledge, common practice in the wind industry. The remaining controllers are developed using state-space multiple-input and multiple-output (MIMO) techniques to explicity account for coupling between loops and to optimize given known frequency structures of the turbine and disturbance. In this first publication from the study, we present the structure of the ongoing controller comparison experiment, the design process for the two controllers compared in this phase, and initial comparison results obtained in field-testing.« less

Temporal redistribution of inhibition over neuronal subcellular domains underlies state-dependent rhythmic change of excitability in the hippocampus

PubMed Central

Somogyi, Peter; Katona, Linda; Klausberger, Thomas; Lasztóczi, Bálint; Viney, Tim J.

2014-01-01

The behaviour-contingent rhythmic synchronization of neuronal activity is reported by local field potential oscillations in the theta, gamma and sharp wave-related ripple (SWR) frequency ranges. In the hippocampus, pyramidal cell assemblies representing temporal sequences are coordinated by GABAergic interneurons selectively innervating specific postsynaptic domains, and discharging phase locked to network oscillations. We compare the cellular network dynamics in the CA1 and CA3 areas recorded with or without anaesthesia. All parts of pyramidal cells, except the axon initial segment, receive GABA from multiple interneuron types, each with distinct firing dynamics. The axon initial segment is exclusively innervated by axo-axonic cells, preferentially firing after the peak of the pyramidal layer theta cycle, when pyramidal cells are least active. Axo-axonic cells are inhibited during SWRs, when many pyramidal cells fire synchronously. This dual inverse correlation demonstrates the key inhibitory role of axo-axonic cells. Parvalbumin-expressing basket cells fire phase locked to field gamma activity in both CA1 and CA3, and also strongly increase firing during SWRs, together with dendrite-innervating bistratified cells, phasing pyramidal cell discharge. Subcellular domain-specific GABAergic innervation probably developed for the coordination of multiple glutamatergic inputs on different parts of pyramidal cells through the temporally distinct activity of GABAergic interneurons, which differentially change their firing during different network states. PMID:24366131

The stress-buffering effects of hope on changes in adjustment to caregiving in multiple sclerosis.

PubMed

Madan, Sindia; Pakenham, Kenneth I

2015-09-01

This study examined the direct and stress-buffering effects of global hope and its components (agency and pathways) on changes in adjustment to multiple sclerosis caregiving over 12 months. A total of 140 carers and their care-recipients completed questionnaires at Time 1 and 12 months later, Time 2. Focal predictors were stress, hope, agency and pathways, and the adjustment outcomes were anxiety, depression, positive affect, positive states of mind and life satisfaction. Results showed that as predicted, greater hope was associated with better adjustment after controlling for the effects of initial adjustment and caregiving and care-recipient illness variables. No stress-buffering effects of hope emerged. Regarding hope components, only the agency dimension emerged as a significant predictor of adjustment. Findings highlight hope as an important protective resource for coping with multiple sclerosis caregiving and underscore the role of agency thinking in this process. © The Author(s) 2013.

A Sequential Ensemble Prediction System at Convection Permitting Scales

NASA Astrophysics Data System (ADS)

Milan, M.; Simmer, C.

2012-04-01

A Sequential Assimilation Method (SAM) following some aspects of particle filtering with resampling, also called SIR (Sequential Importance Resampling), is introduced and applied in the framework of an Ensemble Prediction System (EPS) for weather forecasting on convection permitting scales, with focus to precipitation forecast. At this scale and beyond, the atmosphere increasingly exhibits chaotic behaviour and non linear state space evolution due to convectively driven processes. One way to take full account of non linear state developments are particle filter methods, their basic idea is the representation of the model probability density function by a number of ensemble members weighted by their likelihood with the observations. In particular particle filter with resampling abandons ensemble members (particles) with low weights restoring the original number of particles adding multiple copies of the members with high weights. In our SIR-like implementation we substitute the likelihood way to define weights and introduce a metric which quantifies the "distance" between the observed atmospheric state and the states simulated by the ensemble members. We also introduce a methodology to counteract filter degeneracy, i.e. the collapse of the simulated state space. To this goal we propose a combination of resampling taking account of simulated state space clustering and nudging. By keeping cluster representatives during resampling and filtering, the method maintains the potential for non linear system state development. We assume that a particle cluster with initially low likelihood may evolve in a state space with higher likelihood in a subsequent filter time thus mimicking non linear system state developments (e.g. sudden convection initiation) and remedies timing errors for convection due to model errors and/or imperfect initial condition. We apply a simplified version of the resampling, the particles with highest weights in each cluster are duplicated; for the model evolution for each particle pair one particle evolves using the forward model; the second particle, however, is nudged to the radar and satellite observation during its evolution based on the forward model.

An Enhanced Differential Evolution Algorithm Based on Multiple Mutation Strategies.

PubMed

Xiang, Wan-li; Meng, Xue-lei; An, Mei-qing; Li, Yin-zhen; Gao, Ming-xia

2015-01-01

Differential evolution algorithm is a simple yet efficient metaheuristic for global optimization over continuous spaces. However, there is a shortcoming of premature convergence in standard DE, especially in DE/best/1/bin. In order to take advantage of direction guidance information of the best individual of DE/best/1/bin and avoid getting into local trap, based on multiple mutation strategies, an enhanced differential evolution algorithm, named EDE, is proposed in this paper. In the EDE algorithm, an initialization technique, opposition-based learning initialization for improving the initial solution quality, and a new combined mutation strategy composed of DE/current/1/bin together with DE/pbest/bin/1 for the sake of accelerating standard DE and preventing DE from clustering around the global best individual, as well as a perturbation scheme for further avoiding premature convergence, are integrated. In addition, we also introduce two linear time-varying functions, which are used to decide which solution search equation is chosen at the phases of mutation and perturbation, respectively. Experimental results tested on twenty-five benchmark functions show that EDE is far better than the standard DE. In further comparisons, EDE is compared with other five state-of-the-art approaches and related results show that EDE is still superior to or at least equal to these methods on most of benchmark functions.

Sea surface temperature predictions using a multi-ocean analysis ensemble scheme

NASA Astrophysics Data System (ADS)

Zhang, Ying; Zhu, Jieshun; Li, Zhongxian; Chen, Haishan; Zeng, Gang

2017-08-01

This study examined the global sea surface temperature (SST) predictions by a so-called multiple-ocean analysis ensemble (MAE) initialization method which was applied in the National Centers for Environmental Prediction (NCEP) Climate Forecast System Version 2 (CFSv2). Different from most operational climate prediction practices which are initialized by a specific ocean analysis system, the MAE method is based on multiple ocean analyses. In the paper, the MAE method was first justified by analyzing the ocean temperature variability in four ocean analyses which all are/were applied for operational climate predictions either at the European Centre for Medium-range Weather Forecasts or at NCEP. It was found that these systems exhibit substantial uncertainties in estimating the ocean states, especially at the deep layers. Further, a set of MAE hindcasts was conducted based on the four ocean analyses with CFSv2, starting from each April during 1982-2007. The MAE hindcasts were verified against a subset of hindcasts from the NCEP CFS Reanalysis and Reforecast (CFSRR) Project. Comparisons suggested that MAE shows better SST predictions than CFSRR over most regions where ocean dynamics plays a vital role in SST evolutions, such as the El Niño and Atlantic Niño regions. Furthermore, significant improvements were also found in summer precipitation predictions over the equatorial eastern Pacific and Atlantic oceans, for which the local SST prediction improvements should be responsible. The prediction improvements by MAE imply a problem for most current climate predictions which are based on a specific ocean analysis system. That is, their predictions would drift towards states biased by errors inherent in their ocean initialization system, and thus have large prediction errors. In contrast, MAE arguably has an advantage by sampling such structural uncertainties, and could efficiently cancel these errors out in their predictions.

Occupational Therapy and Management of Multiple Chronic Conditions in the Context of Health Care Reform

PubMed Central

Fogelberg, Donald J.; Halle, Ashley D.; Mroz, Tracy M.

2017-01-01

One in four individuals living in the United States has multiple chronic conditions (MCCs), and the already high prevalence of MCCs continues to grow. This population has high rates of health care utilization yet poor outcomes, leading to elevated concerns about fragmented, low-quality care provided within the current health care system. Several national initiatives endeavor to improve care for the population with MCCs, and occupational therapy is uniquely positioned to contribute to these efforts for more efficient, effective, client-centered management of care. By integrating findings from the literature with current policy and practice, we aim to highlight the potential role for occupational therapy in managing MCCs within the evolving health care system. PMID:28027031

New insights into mechanistic photoisomerization of ethylene-bridged azobenzene from ab initio multiple spawning simulation.

PubMed

Liu, Lihong; Wang, Yating; Fang, Qiu

2017-02-14

Ethylene-bridged azobenzene (br-AB) has aroused broad interests due to its unique photoswitching properties. Numerous dynamical simulations have been performed for the br-AB photoisomerization, which focused mainly on the conformational effect and the funnel role of minimum-energy conical intersection (MECI) on the mechanism. In the present work, we use the "full quantum" ab initio multiple spawning method to simulate the br-AB photoisomerization, which provides new insights into the mechanism. Upon irradiation of br-AB to the first excited singlet state (S 1 ), most of the excess energies are trapped in the azo-moiety. Since the intramolecular vibrational energy redistribution is slower than the S 1 relaxation processes, the nonadiabatic transition from S 1 to the ground state (S 0 ) occurs in the vicinity of high-energy crossing seam and even the largest probabilities of the S 1 → S 0 transition are not distributed in the MECI regions. Once decaying to the S 0 state through the high-energy region, the subsequent isomerization and re-formation of the initial isomer are ultrafast processes in the S 0 state. It is the nonergodic behavior of the S 1 and S 0 dynamics that is mainly responsible for the unique photoswitching properties of the ethylene-bridged azobenzene, which will be discussed in detail.

Update on risk stratification and treatment of newly diagnosed multiple myeloma.

PubMed

Kapoor, Prashant; Rajkumar, S Vincent

2011-10-01

Multiple myeloma is the second most common hematologic malignancy. Chromosomal aberrations are important prognostic determinants that influence the clinical decision-making in newly-diagnosed multiple myeloma (NDMM). Patients are considered high-risk if any of the following features are detected: hypodiploidy, deletion 13 by cytogenetics, t(4;14), t(14;16), t(14;20) and/or 17 p deletion. In the absence of these features patients are considered standard risk. Outside of trials, risk-adapted therapy in the transplant-eligible high-risk patients advocates use of bortezomib-based induction therapy followed by autologous stem cell transplantation (ASCT) and bortezomib-based maintenance therapy. High-risk, transplant-ineligible patients should also utilize bortezomib as initial therapy since it is known to overcome the poor prognosis associated with some high-risk features. The goal of therapy in high-risk patients is to attain and maintain a state of complete remission as much as possible. In contrast, the standard-risk, transplant-eligible patients may be treated with either lenalidomide-dexamethasone or bortezomib-based therapy followed by ASCT. In such patients, ASCT can also be deferred until first relapse if the patients are tolerating initial therapy well. Lenalidomide maintenance therapy in the post-transplant setting in standard-risk patients is controversial and not recommended routinely. For transplant-ineligible standard-risk patients, multiple options exist, although in the absence direct comparisons, we prefer lenalidomide plus low-dose dexamethasone over melphalan-based combinations. This review outlines evidence-based management approaches in NDMM, with a focus on risk-adapted therapy.

Health care administrators' perspectives on the role of absorptive capacity for strategic change initiatives: a qualitative study.

PubMed

Kash, Bita A; Spaulding, Aaron; Gamm, Larry; Johnson, Christopher E

2013-01-01

The dimensions of absorptive capacity (ACAP) are defined, and the importance of ACAP is established in the management literature, but the concept has not been applied to health care organizations attempting to implement multiple strategic initiatives. The aim of this study was to test the utility of ACAP by analyzing health care administrators' experiences with multiple strategic initiatives within two health systems. Results are drawn from administrators' assessments of multiple initiatives within two health systems using in-depth personal interviews with a total of 61 health care administrators. Data analysis was performed following deductive qualitative analysis guidelines. Interview transcripts were coded based on the four dimensions of ACAP: acquiring, assimilating, internalizing/transforming, and exploiting knowledge. Furthermore, we link results related to utilization of management resources, including number of key personnel involved and time consumption, to dimensions of ACAP. Participants' description of multiple strategic change initiatives confirmed the importance of the four ACAP dimensions. ACAP can be a useful framework to assess organizational capacity with respect to the organization's ability to concurrently implement multiple strategic initiatives. This capacity specifically revolves around human capital requirements from upper management based on the initiatives' location or stage within the ACAP framework. Strategic change initiatives in health care can be usefully viewed from an ACAP perspective. There is a tendency for those strategic initiatives ranking higher in priority and time consumption to reflect more advanced dimensions of ACAP (assimilate and transform), whereas few initiatives were identified in the ACAP "exploit" dimension. This may suggest that health care leaders tend to no longer identify as strategic initiatives those innovations that have moved to the exploitation stage or that less attention is given to the exploitation elements of a strategic initiative than to the earlier stages.

Nonlinear modelling of high-speed catenary based on analytical expressions of cable and truss elements

NASA Astrophysics Data System (ADS)

Song, Yang; Liu, Zhigang; Wang, Hongrui; Lu, Xiaobing; Zhang, Jing

2015-10-01

Due to the intrinsic nonlinear characteristics and complex structure of the high-speed catenary system, a modelling method is proposed based on the analytical expressions of nonlinear cable and truss elements. The calculation procedure for solving the initial equilibrium state is proposed based on the Newton-Raphson iteration method. The deformed configuration of the catenary system as well as the initial length of each wire can be calculated. Its accuracy and validity of computing the initial equilibrium state are verified by comparison with the separate model method, absolute nodal coordinate formulation and other methods in the previous literatures. Then, the proposed model is combined with a lumped pantograph model and a dynamic simulation procedure is proposed. The accuracy is guaranteed by the multiple iterative calculations in each time step. The dynamic performance of the proposed model is validated by comparison with EN 50318, the results of the finite element method software and SIEMENS simulation report, respectively. At last, the influence of the catenary design parameters (such as the reserved sag and pre-tension) on the dynamic performance is preliminarily analysed by using the proposed model.

Ab initio metadynamics simulations of oxygen/ligand interactions in organoaluminum clusters

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

Alnemrat, Sufian; Hooper, Joseph P., E-mail: jphooper@nps.edu

2014-10-14

Car-Parrinello molecular dynamics combined with a metadynamics algorithm is used to study the initial interaction of O{sub 2} with the low-valence organoaluminum clusters Al{sub 4}Cp{sub 4} (Cp=C{sub 5}H{sub 5}) and Al{sub 4}Cp{sub 4}{sup *} (Cp{sup *}=C{sub 5}[CH{sub 3}]{sub 5}). Prior to reaction with the aluminum core, simulations suggest that the oxygen undergoes a hindered crossing of the steric barrier presented by the outer ligand monolayer. A combination of two collective variables based on aluminum/oxygen distance and lateral oxygen displacement was found to produce distinct reactant, product, and transition states for this process. In the methylated cluster with Cp{sup *} ligands,more » a broad transition state of 45 kJ/mol was observed due to direct steric interactions with the ligand groups and considerable oxygen reorientation. In the non-methylated cluster the ligands distort away from the oxidizer, resulting in a barrier of roughly 34 kJ/mol with minimal O{sub 2} reorientation. A study of the oxygen/cluster system fixed in a triplet multiplicity suggests that the spin state does not affect the initial steric interaction with the ligands. The metadynamics approach appears to be a promising means of analyzing the initial steps of such oxidation reactions for ligand-protected clusters.« less

Nucleosomes influence multiple steps during replication initiation

PubMed Central

Azmi, Ishara F; Watanabe, Shinya; Maloney, Michael F; Kang, Sukhyun; Belsky, Jason A; MacAlpine, David M; Peterson, Craig L; Bell, Stephen P

2017-01-01

Eukaryotic replication origin licensing, activation and timing are influenced by chromatin but a mechanistic understanding is lacking. Using reconstituted nucleosomal DNA replication assays, we assessed the impact of nucleosomes on replication initiation. To generate distinct nucleosomal landscapes, different chromatin-remodeling enzymes (CREs) were used to remodel nucleosomes on origin-DNA templates. Nucleosomal organization influenced two steps of replication initiation: origin licensing and helicase activation. Origin licensing assays showed that local nucleosome positioning enhanced origin specificity and modulated helicase loading by influencing ORC DNA binding. Interestingly, SWI/SNF- and RSC-remodeled nucleosomes were permissive for origin licensing but showed reduced helicase activation. Specific CREs rescued replication of these templates if added prior to helicase activation, indicating a permissive chromatin state must be established during origin licensing to allow efficient origin activation. Our studies show nucleosomes directly modulate origin licensing and activation through distinct mechanisms and provide insights into the regulation of replication initiation by chromatin. DOI: http://dx.doi.org/10.7554/eLife.22512.001 PMID:28322723

Structural dynamics of ribosome subunit association studied by mixing-spraying time-resolved cryo-EM

PubMed Central

Chen, Bo; Kaledhonkar, Sandip; Sun, Ming; Shen, Bingxin; Lu, Zonghuan; Barnard, David; Lu, Toh-Ming; Gonzalez, Ruben L.; Frank, Joachim

2015-01-01

Ribosomal subunit association is a key checkpoint in translation initiation, but its structural dynamics are poorly understood. Here, we used a recently developed mixing-spraying, time-resolved, cryogenic electron microscopy (cryo-EM) method to study ribosomal subunit association in the sub-second time range. We have improved this method and increased the cryo-EM data yield by tenfold. Pre-equilibrium states of the association reaction were captured by reacting the mixture of ribosomal subunits for 60 ms and 140 ms. We also identified three distinct ribosome conformations in the associated ribosomes. The observed proportions of these conformations are the same in these two time points, suggesting that ribosomes equilibrate among the three conformations within less than 60 ms upon formation. Our results demonstrate that the mixing-spraying method can capture multiple states of macromolecules during a sub-second reaction. Other fast processes, such as translation initiation, decoding and ribosome recycling, are amenable to study with this method. PMID:26004440

Far-red light photoactivatable near-infrared fluorescent proteins engineered from a bacterial phytochrome.

PubMed

Piatkevich, Kiryl D; Subach, Fedor V; Verkhusha, Vladislav V

2013-01-01

The ability to modulate the fluorescence of optical probes can be used to enhance signal-to-noise ratios for imaging within highly autofluorescent environments, such as intact tissues and living organisms. Here, we report two bacteriophytochrome-based photoactivatable near-infrared fluorescent proteins, named PAiRFP1 and PAiRFP2. PAiRFPs utilize haem-derived biliverdin, ubiquitous in mammalian tissues, as the chromophore. Initially weakly fluorescent PAiRFPs undergo photoconversion into a highly fluorescent state with excitation/emission at 690/717 nm following a brief irradiation with far-red light. After photoactivation, PAiRFPs slowly revert back to initial state, enabling multiple photoactivation-relaxation cycles. Low-temperature optical spectroscopy reveals several intermediates involved in PAiRFP photocycles, which all differ from that of the bacteriophytochrome precursor. PAiRFPs can be photoactivated in a spatially selective manner in mouse tissues, and optical modulation of their fluorescence allows for substantial contrast enhancement, making PAiRFPs advantageous over permanently fluorescent probes for in vivo imaging conditions of high autofluorescence and low signal levels.

Modeling target normal sheath acceleration using handoffs between multiple simulations

NASA Astrophysics Data System (ADS)

McMahon, Matthew; Willis, Christopher; Mitchell, Robert; King, Frank; Schumacher, Douglass; Akli, Kramer; Freeman, Richard

2013-10-01

We present a technique to model the target normal sheath acceleration (TNSA) process using full-scale LSP PIC simulations. The technique allows for a realistic laser, full size target and pre-plasma, and sufficient propagation length for the accelerated ions and electrons. A first simulation using a 2D Cartesian grid models the laser-plasma interaction (LPI) self-consistently and includes field ionization. Electrons accelerated by the laser are imported into a second simulation using a 2D cylindrical grid optimized for the initial TNSA process and incorporating an equation of state. Finally, all of the particles are imported to a third simulation optimized for the propagation of the accelerated ions and utilizing a static field solver for initialization. We also show use of 3D LPI simulations. Simulation results are compared to recent ion acceleration experiments using SCARLET laser at The Ohio State University. This work was performed with support from ASOFR under contract # FA9550-12-1-0341, DARPA, and allocations of computing time from the Ohio Supercomputing Center.

Ultrafast dynamics of exciton fission in polycrystalline pentacene.

PubMed

Wilson, Mark W B; Rao, Akshay; Clark, Jenny; Kumar, R Sai Santosh; Brida, Daniele; Cerullo, Giulio; Friend, Richard H

2011-08-10

We use ultrafast transient absorption spectroscopy with sub-20 fs time resolution and broad spectral coverage to directly probe the process of exciton fission in polycrystalline thin films of pentacene. We observe that the overwhelming majority of initially photogenerated singlet excitons evolve into triplet excitons on an ∼80 fs time scale independent of the excitation wavelength. This implies that exciton fission occurs at a rate comparable to phonon-mediated exciton localization processes and may proceed directly from the initial, delocalized, state. The singlet population is identified due to the brief presence of stimulated emission, which is emitted at wavelengths which vary with the photon energy of the excitation pulse, a violation of Kasha's Rule that confirms that the lowest-lying singlet state is extremely short-lived. This direct demonstration that triplet generation is both rapid and efficient establishes multiple exciton generation by exciton fission as an attractive route to increased efficiency in organic solar cells. © 2011 American Chemical Society

Lifetime and current sexual assault and harassment victimization rates of active-duty United States Air Force women.

PubMed

Bostock, Deborah J; Daley, James G

2007-09-01

From a stratified random sample, 2,018 active-duty United States Air Force women completed a telephone survey dealing with sexual assault and harassment. The lifetime prevalence of rape among Air Force women (28%) was more than twice as high as the prevalence in a national sample (13%). Nearly half of the military sample had been the victims of rape, molestation, or attempted sexual assault. The majority of both initial rapes (75%) and most recent rapes (56%) involved assault by civilians when the victims were civilians. Family members perpetrated 29% of initial rapes and 33% of most recent rapes. Regarding military status of the perpetrator, 14% of first-time victims were raped by a military member, 26% of multiple-time victims were raped by a military member, 31.8% of military women were sexually harassed by a military supervisor or boss, and 26.7% of military women were sexually harassed by a military coworker.

Ca 3d unoccupied states in Bi2Sr2CaCu2O8 investigated by Ca L2,3 x-ray-absorption near-edge structure

NASA Astrophysics Data System (ADS)

Borg, A.; King, P. L.; Pianetta, P.; Lindau, I.; Mitzi, D. B.; Kapitulnik, A.; Soldatov, A. V.; della Longa, S.; Bianconi, A.

1992-10-01

The high-resolution Ca L2,3 x-ray-absorption near-edge-structure (XANES) spectrum of a Bi2Sr2CaCu2O8 single crystal has been measured by use of a magnetic-projection x-ray microscope probing a surface area of 200×200 μm2. The Ca L2,3 XANES spectrum is analyzed by performing a multiple-scattering XANES calculation in real space and comparing the results with the spectrum of CaF2. Good agreement between the calculated and experimental crystal-field splitting Δf of the Ca 3d final states is found and the splitting is shown to be smaller by 0.5 eV than in the initial state. The Ca 3d partial density of states is found to be close to the Fermi level in the initial state. The Ca-O(in plane) distance is shown to be a critical parameter associated with the shift of the Ca 3d states relative to the Fermi level; in particular, we have studied the effect of the out-of-plane dimpling mode of the in-plane oxygen atoms O(in plane) that will move the Ca 3d states on or off the Fermi level. This mode can therefore play a role in modulating the charge transfer between the two CuO2 planes separated by the Ca ions.

INSPIRE: Initiating New Science Partnerships in Rural Education

NASA Astrophysics Data System (ADS)

Pierce, Donna M.; McNeal, K. S.; Bruce, L. M.; Harpole, S. H.; Schmitz, D. W.

2010-10-01

INSPIRE, Initiating New Science Partnerships in Rural Education, is a partnership between Mississippi State University and three school districts in Mississippi's Golden Triangle (Starkville, Columbus, West Point). This program recruits ten graduate fellows each year from geosciences, physics, astronomy, and engineering and pairs them with a participating middle school or high school teacher. The graduate fellows provide technology-supported inquiry-based learning in the earth and space sciences by incorporating their research into classroom instruction and using multiple resources such as Google Earth, geographic information systems (GIS), Celestia, and others. In addition to strengthening the communication skills of the graduate fellows, INSPIRE will increase the content knowledge of participating teachers, provide high-quality instruction using multiple technologies, promote higher education to area high-school students, and provide fellows and teachers with international research experience through our partners in Australia, The Bahamas, England, and Poland. INSPIRE is funded by the Graduate STEM Fellows in K-12 Education Program (GK-12; Award No. DGE-0947419), which is part of the Division for Graduate Education of the National Science Foundation.

National Hydropower Plant Dataset, Version 1 (Update FY18Q2)

DOE Data Explorer

Samu, Nicole; Kao, Shih-Chieh; O'Connor, Patrick; Johnson, Megan; Uria-Martinez, Rocio; McManamay, Ryan

2016-09-30

The National Hydropower Plant Dataset, Version 1, Update FY18Q2, includes geospatial point-level locations and key characteristics of existing hydropower plants in the United States that are currently online. These data are a subset extracted from NHAAP’s Existing Hydropower Assets (EHA) dataset, which is a cornerstone of NHAAP’s EHA effort that has supported multiple U.S. hydropower R&D research initiatives related to market acceleration, environmental impact reduction, technology-to-market activities, and climate change impact assessment.

Aircraft Dynamic Response to Damaged and Repaired Runways.

DTIC Science & Technology

1982-08-01

is particularly beneficial in giving the engineer a fast understanding of problems encountered. This can extend, if required, to computer animation of...pitch response following a repair for a selection of ’critical’ initial states o animation of time history responses o routines, for the multiple repair...forms L𔄀&alit6 so produit on css do glissement avao ~ed i/~ Ct am :ooefficient do laminago do l’huilo, eat dittdrant ontro is d6tonte at i’ontonoeent at

Predicting 2D target velocity cannot help 2D motion integration for smooth pursuit initiation.

PubMed

Montagnini, Anna; Spering, Miriam; Masson, Guillaume S

2006-12-01

Smooth pursuit eye movements reflect the temporal dynamics of bidimensional (2D) visual motion integration. When tracking a single, tilted line, initial pursuit direction is biased toward unidimensional (1D) edge motion signals, which are orthogonal to the line orientation. Over 200 ms, tracking direction is slowly corrected to finally match the 2D object motion during steady-state pursuit. We now show that repetition of line orientation and/or motion direction does not eliminate the transient tracking direction error nor change the time course of pursuit correction. Nonetheless, multiple successive presentations of a single orientation/direction condition elicit robust anticipatory pursuit eye movements that always go in the 2D object motion direction not the 1D edge motion direction. These results demonstrate that predictive signals about target motion cannot be used for an efficient integration of ambiguous velocity signals at pursuit initiation.

Parameter identification of thermophilic anaerobic degradation of valerate.

PubMed

Flotats, Xavier; Ahring, Birgitte K; Angelidaki, Irini

2003-01-01

The considered mathematical model of the decomposition of valerate presents three unknown kinetic parameters, two unknown stoichiometric coefficients, and three unknown initial concentrations for biomass. Applying a structural identifiability study, we concluded that it is necessary to perform simultaneous batch experiments with different initial conditions for estimating these parameters. Four simultaneous batch experiments were conducted at 55 degrees C, characterized by four different initial acetate concentrations. Product inhibition of valerate degradation by acetate was considered. Practical identification was done optimizing the sum of the multiple determination coefficients for all measured state variables and for all experiments simultaneously. The estimated values of kinetic parameters and stoichiometric coefficients were characterized by the parameter correlation matrix, the confidence interval, and the student's t-test at 5% significance level with positive results except for the saturation constant, for which more experiments for improving its identifiability should be conducted. In this article, we discuss kinetic parameter estimation methods.

Initiation of DNA replication requires actin dynamics and formin activity.

PubMed

Parisis, Nikolaos; Krasinska, Liliana; Harker, Bethany; Urbach, Serge; Rossignol, Michel; Camasses, Alain; Dewar, James; Morin, Nathalie; Fisher, Daniel

2017-11-02

Nuclear actin regulates transcriptional programmes in a manner dependent on its levels and polymerisation state. This dynamics is determined by the balance of nucleocytoplasmic shuttling, formin- and redox-dependent filament polymerisation. Here, using Xenopus egg extracts and human somatic cells, we show that actin dynamics and formins are essential for DNA replication. In proliferating cells, formin inhibition abolishes nuclear transport and initiation of DNA replication, as well as general transcription. In replicating nuclei from transcriptionally silent Xenopus egg extracts, we identified numerous actin regulators, and disruption of actin dynamics abrogates nuclear transport, preventing NLS (nuclear localisation signal)-cargo release from RanGTP-importin complexes. Nuclear formin activity is further required to promote loading of cyclin-dependent kinase (CDK) and proliferating cell nuclear antigen (PCNA) onto chromatin, as well as initiation and elongation of DNA replication. Therefore, actin dynamics and formins control DNA replication by multiple direct and indirect mechanisms. © 2017 The Authors.

Education and Public Outreach

NASA Technical Reports Server (NTRS)

Sakimoto, Philip (Editor)

2000-01-01

This Annual Report is a summary of nearly 400 Education and Public Outreach (E/PO) products and activities developed or carried out in FY2000 under NASA's Office of Space Science (OSS) E/PO program. It includes products and activities developed by OSS missions and research programs, innovative space science concepts developed under the Initiative to Develop Education through Astronomy and Space Science (IDEAS) Program, projects initiated under the Minority University Education and Research Partnership Initiative in Space Science, and a number of additional comprehensive or special purpose programs managed by OSS at NASA Headquarters. Taking into account the fact that many of the activities reported involve multiple events that took place in a variety of venues, the total number of E/PO events reported for FY2000 is over 1,500, with events having taken place in all 50 states, the District of Columbia, one US Territory (Guam), and four foreign nations (Australia, Canada, Mexico, and Peru).

Electron-impact vibrational relaxation in high-temperature nitrogen

NASA Technical Reports Server (NTRS)

Lee, Jong-Hun

1992-01-01

Vibrational relaxation process of N2 molecules by electron-impact is examined for the future planetary entry environments. Multiple-quantum transitions from excited states to higher/lower states are considered for the electronic ground state of the nitrogen molecule N2 (X 1Sigma-g(+)). Vibrational excitation and deexcitation rate coefficients obtained by computational quantum chemistry are incorporated into the 'diffusion model' to evaluate the time variations of vibrational number densities of each energy state and total vibrational energy. Results show a non-Boltzmann distribution of number densities at the earlier stage of relaxation, which in turn suppresses the equilibrium process but affects little the time variation of total vibrational energy. An approximate rate equation and a corresponding relaxation time from the excited states, compatible with the system of flow conservation equations, are derived. The relaxation time from the excited states indicates the weak dependency of the initial vibrational temperature. The empirical curve-fit formula for the improved e-V relaxation time is obtained.

A study of roll attractor and wing rock of delta wings at high angles of attack

NASA Technical Reports Server (NTRS)

Niranjana, T.; Rao, D. M.; Pamadi, Bandu N.

1993-01-01

Wing rock is a high angle of attack dynamic phenomenon of limited cycle motion predominantly in roll. The wing rock is one of the limitations to combat effectiveness of the fighter aircraft. Roll Attractor is the steady state or equilibrium trim angle (phi(sub trim)) attained by the free-to-roll model, held at some angle of attack, and released form rest at a given initial roll (bank) angle (phi(sub O)). Multiple roll attractors are attained at different trim angles depending on initial roll angle. The test facility (Vigyan's low speed wind tunnel) and experimental work is presented here along with mathematical modelling of roll attractor phenomenon and analysis and comparison of predictions with experimental data.

Medical marijuana: legal considerations.

PubMed

Schouten, J T

1999-01-01

In 1998, Washington State passed a law, Initiative 692 (I-692), that gives individuals who are charged with possession of marijuana for medical purposes a possible affirmative defense. The law lets these individuals provide a note from their doctor or a copy of their medical records stating they have a condition that may benefit from the use of marijuana. I-692 does not legalize the medical use of marijuana and does not affect Federal law, which makes obtaining, possessing, and growing marijuana illegal. The Washington law limits the amount of marijuana a patient can possess to a 60-day supply and defines the conditions for which medical marijuana may be used. These conditions include HIV, cancer, multiple sclerosis, and epilepsy.

Strategies in a symmetric quantum Kolkata restaurant problem

NASA Astrophysics Data System (ADS)

Sharif, Puya; Heydari, Hoshang

2012-12-01

The Quantum Kolkata restaurant problem is a multiple-choice version of the quantum minority game, where a set of n non-communicating players have to chose between one of m choices. A payoff is granted to the players that make a unique choice. It has previously been shown that shared entanglement and quantum operations can aid the players to coordinate their actions and acquire higher payoffs than is possible with classical randomization. In this paper the initial quantum state is expanded to a family of GHZ-type states and strategies are discussed in terms of possible final outcomes. It is shown that the players individually seek outcomes that maximize the collective good.

Probing energy transfer events in the light harvesting complex 2 (LH2) of Rhodobacter sphaeroides with two-dimensional spectroscopy.

PubMed

Fidler, Andrew F; Singh, Ved P; Long, Phillip D; Dahlberg, Peter D; Engel, Gregory S

2013-10-21

Excitation energy transfer events in the photosynthetic light harvesting complex 2 (LH2) of Rhodobacter sphaeroides are investigated with polarization controlled two-dimensional electronic spectroscopy. A spectrally broadened pulse allows simultaneous measurement of the energy transfer within and between the two absorption bands at 800 nm and 850 nm. The phased all-parallel polarization two-dimensional spectra resolve the initial events of energy transfer by separating the intra-band and inter-band relaxation processes across the two-dimensional map. The internal dynamics of the 800 nm region of the spectra are resolved as a cross peak that grows in on an ultrafast time scale, reflecting energy transfer between higher lying excitations of the B850 chromophores into the B800 states. We utilize a polarization sequence designed to highlight the initial excited state dynamics which uncovers an ultrafast transfer component between the two bands that was not observed in the all-parallel polarization data. We attribute the ultrafast transfer component to energy transfer from higher energy exciton states to lower energy states of the strongly coupled B850 chromophores. Connecting the spectroscopic signature to the molecular structure, we reveal multiple relaxation pathways including a cyclic transfer of energy between the two rings of the complex.

Single and multiple ionization of C{sub 60} fullerenes and collective effects in collisions with highly charged C, F, and Si ions with energy 3 MeV/u

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

Kelkar, A. H.; Kadhane, U.; Misra, D.

2010-10-15

We have measured absolute cross sections for single, double, triple, and quadruple ionization of C{sub 60} in collisions with 3 MeV/u C, F, and Si projectile ions at various projectile charge states. The experiment was performed using the recoil-ion time-of-flight technique. Projectile charge state dependence of the ionization yields was compared mainly with a model based on the giant dipole plasmon resonance (GDPR). In some cases, the continuum-distorted-wave-eikonal-initial-state (CDW-EIS) model which is normally applied for ion-atom collisions was also used as a reference. An excellent qualitative agreement between the experimental data for single and double ionization and the GDPR modelmore » predictions was found for all projectile charge states.« less

Concept Mapping for Planning and Evaluation of a Community-Based Initiative

ERIC Educational Resources Information Center

Chiu, Korinne

2012-01-01

Community-based initiatives address community issues by providing a multi-agency approach to prevention and intervention services (Connell et al.,1995). When incorporating multiple agencies, it can be challenging to obtain multiple perspectives and gaining consensus on the priorities and direction for these initiatives. This study employed a…

Molecular mechanisms of "off-on switch" of activities of human IDH1 by tumor-associated mutation R132H.

PubMed

Yang, Bei; Zhong, Chen; Peng, Yingjie; Lai, Zheng; Ding, Jianping

2010-11-01

Human cytosolic NADP-IDH (IDH1) has recently been found to be involved in tumorigenesis. Notably, the tumor-derived IDH1 mutations identified so far mainly occur at Arg132, and mutation R132H is the most prevalent one. This mutation impairs the oxidative IDH activity of the enzyme, but renders a new reduction function of converting α-ketoglutarate (αKG) to 2-hydroxyglutarate. Here, we report the structures of the R132H mutant IDH1 with and without isocitrate (ICT) bound. The structural data together with mutagenesis and biochemical data reveal a previously undefined initial ICT-binding state and demonstrate that IDH activity requires a conformational change to a closed pre-transition state. Arg132 plays multiple functional roles in the catalytic reaction; in particular, the R132H mutation hinders the conformational changes from the initial ICT-binding state to the pre-transition state, leading to the impairment of the IDH activity. Our results describe for the first time that there is an intermediate conformation that corresponds to an initial ICT-binding state and that the R132H mutation can trap the enzyme in this conformation, therefore shedding light on the molecular mechanism of the "off switch" of the potentially tumor-suppressive IDH activity. Furthermore, we proved the necessity of Tyr139 for the gained αKG reduction activity and propose that Tyr139 may play a vital role by compensating the increased negative charge on the C2 atom of αKG during the transfer of a hydride anion from NADPH to αKG, which provides new insights into the mechanism of the "on switch" of the hypothetically oncogenic reduction activity of IDH1 by this mutation.

A MAD-Bayes Algorithm for State-Space Inference and Clustering with Application to Querying Large Collections of ChIP-Seq Data Sets.

PubMed

Zuo, Chandler; Chen, Kailei; Keleş, Sündüz

2017-06-01

Current analytic approaches for querying large collections of chromatin immunoprecipitation followed by sequencing (ChIP-seq) data from multiple cell types rely on individual analysis of each data set (i.e., peak calling) independently. This approach discards the fact that functional elements are frequently shared among related cell types and leads to overestimation of the extent of divergence between different ChIP-seq samples. Methods geared toward multisample investigations have limited applicability in settings that aim to integrate 100s to 1000s of ChIP-seq data sets for query loci (e.g., thousands of genomic loci with a specific binding site). Recently, Zuo et al. developed a hierarchical framework for state-space matrix inference and clustering, named MBASIC, to enable joint analysis of user-specified loci across multiple ChIP-seq data sets. Although this versatile framework estimates both the underlying state-space (e.g., bound vs. unbound) and also groups loci with similar patterns together, its Expectation-Maximization-based estimation structure hinders its applicability with large number of loci and samples. We address this limitation by developing MAP-based asymptotic derivations from Bayes (MAD-Bayes) framework for MBASIC. This results in a K-means-like optimization algorithm that converges rapidly and hence enables exploring multiple initialization schemes and flexibility in tuning. Comparison with MBASIC indicates that this speed comes at a relatively insignificant loss in estimation accuracy. Although MAD-Bayes MBASIC is specifically designed for the analysis of user-specified loci, it is able to capture overall patterns of histone marks from multiple ChIP-seq data sets similar to those identified by genome-wide segmentation methods such as ChromHMM and Spectacle.

Multiple Objects Fusion Tracker Using a Matching Network for Adaptively Represented Instance Pairs

PubMed Central

Oh, Sang-Il; Kang, Hang-Bong

2017-01-01

Multiple-object tracking is affected by various sources of distortion, such as occlusion, illumination variations and motion changes. Overcoming these distortions by tracking on RGB frames, such as shifting, has limitations because of material distortions caused by RGB frames. To overcome these distortions, we propose a multiple-object fusion tracker (MOFT), which uses a combination of 3D point clouds and corresponding RGB frames. The MOFT uses a matching function initialized on large-scale external sequences to determine which candidates in the current frame match with the target object in the previous frame. After conducting tracking on a few frames, the initialized matching function is fine-tuned according to the appearance models of target objects. The fine-tuning process of the matching function is constructed as a structured form with diverse matching function branches. In general multiple object tracking situations, scale variations for a scene occur depending on the distance between the target objects and the sensors. If the target objects in various scales are equally represented with the same strategy, information losses will occur for any representation of the target objects. In this paper, the output map of the convolutional layer obtained from a pre-trained convolutional neural network is used to adaptively represent instances without information loss. In addition, MOFT fuses the tracking results obtained from each modality at the decision level to compensate the tracking failures of each modality using basic belief assignment, rather than fusing modalities by selectively using the features of each modality. Experimental results indicate that the proposed tracker provides state-of-the-art performance considering multiple objects tracking (MOT) and KITTIbenchmarks. PMID:28420194

Toward a new generation of agricultural system data, models, and knowledge products: State of agricultural systems science.

PubMed

Jones, James W; Antle, John M; Basso, Bruno; Boote, Kenneth J; Conant, Richard T; Foster, Ian; Godfray, H Charles J; Herrero, Mario; Howitt, Richard E; Janssen, Sander; Keating, Brian A; Munoz-Carpena, Rafael; Porter, Cheryl H; Rosenzweig, Cynthia; Wheeler, Tim R

2017-07-01

We review the current state of agricultural systems science, focusing in particular on the capabilities and limitations of agricultural systems models. We discuss the state of models relative to five different Use Cases spanning field, farm, landscape, regional, and global spatial scales and engaging questions in past, current, and future time periods. Contributions from multiple disciplines have made major advances relevant to a wide range of agricultural system model applications at various spatial and temporal scales. Although current agricultural systems models have features that are needed for the Use Cases, we found that all of them have limitations and need to be improved. We identified common limitations across all Use Cases, namely 1) a scarcity of data for developing, evaluating, and applying agricultural system models and 2) inadequate knowledge systems that effectively communicate model results to society. We argue that these limitations are greater obstacles to progress than gaps in conceptual theory or available methods for using system models. New initiatives on open data show promise for addressing the data problem, but there also needs to be a cultural change among agricultural researchers to ensure that data for addressing the range of Use Cases are available for future model improvements and applications. We conclude that multiple platforms and multiple models are needed for model applications for different purposes. The Use Cases provide a useful framework for considering capabilities and limitations of existing models and data.

Toward a New Generation of Agricultural System Data, Models, and Knowledge Products: State of Agricultural Systems Science

NASA Technical Reports Server (NTRS)

Jones, James W.; Antle, John M.; Basso, Bruno; Boote, Kenneth J.; Conant, Richard T.; Foster, Ian; Godfray, H. Charles J.; Herrero, Mario; Howitt, Richard E.; Janssen, Sander;

Toward a new generation of agricultural system data, models, and knowledge products: State of agricultural systems science

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

Jones, James W.; Antle, John M.; Basso, Bruno

We review the current state of agricultural systems science, focusing in particular on the capabilities and limitations of agricultural systems models. We discuss the state of models relative to five different Use Cases spanning field, farm, landscape, regional, and global spatial scales and engaging questions in past, current, and future time periods. Contributions from multiple disciplines have made major advances relevant to a wide range of agricultural system model applications at various spatial and temporal scales. Although current agricultural systems models have features that are needed for the Use Cases, we found that all of them have limitations and needmore » to be improved. We identified common limitations across all Use Cases, namely 1) a scarcity of data for developing, evaluating, and applying agricultural system models and 2) inadequate knowledge systems that effectively communicate model results to society. We argue that these limitations are greater obstacles to progress than gaps in conceptual theory or available methods for using system models. New initiatives on open data show promise for addressing the data problem, but there also needs to be a cultural change among agricultural researchers to ensure that data for addressing the range of Use Cases are available for future model improvements and applications. We conclude that multiple platforms and multiple models are needed for model applications for different purposes. The Use Cases provide a useful framework for considering capabilities and limitations of existing models and data.« less

Surgeon migration between developing countries and the United States: train, retain, and gain from brain drain.

PubMed

Hagander, Lars E; Hughes, Christopher D; Nash, Katherine; Ganjawalla, Karan; Linden, Allison; Martins, Yolanda; Casey, Kathleen M; Meara, John G

2013-01-01

The critical shortage of surgeons in many low- and middle-income countries (LMICs) prevents adequate responses to surgical needs, but the factors that affect surgeon migration have remained incompletely understood. The goal of this study was to examine the importance of personal, professional, and infrastructural factors on surgeon migration from LMICs to the United States. We hypothesized that the main drivers of surgeon migration can be addressed by providing adequate domestic surgical infrastructure, surgical training programs, and viable surgical career paths. We conducted an internet-based nationwide survey of surgeons living in the US who originated from LMICs. 66 surgeons completed the survey. The most influential factors for primary migration were related to professional reasons (p ≤ 0.001). Nonprofessional factors, such as concern for remuneration, family, and security were significantly less important for the initial migration decisions, but adopted a more substantial role in deciding whether or not to return after training in the United States. Migration to the United States was initially considered temporary (44 %), and a majority of the surveyed surgeons have returned to their source countries in some capacity (56 %), often on multiple occasions (80 %), to contribute to clinical work, research, and education. This study suggests that surgically oriented medical graduates from LMICs migrate primarily for professional reasons. Initiatives to improve specialist education and surgical infrastructure in LMICs have the potential to promote retention of the surgical workforce. There may be formal ways for LMICs to gain from the international pool of relocated surgeons.

Recurrent spontaneous motor seizures after repeated low-dose systemic treatment with kainate: assessment of a rat model of temporal lobe epilepsy.

PubMed

Hellier, J L; Patrylo, P R; Buckmaster, P S; Dudek, F E

1998-06-01

Human temporal lobe epilepsy is associated with complex partial seizures that can produce secondarily generalized seizures and motor convulsions. In some patients with temporal lobe epilepsy, the seizures and convulsions occur following a latent period after an initial injury and may progressively increase in frequency for much of the patient's life. Available animal models of temporal lobe epilepsy are produced by acute treatments that often have high mortality rates and/or are associated with a low proportion of animals developing spontaneous chronic motor seizures. In this study, rats were given multiple low-dose intraperitoneal (i.p.) injections of kainate in order to minimize the mortality rate usually associated with single high-dose injections. We tested the hypothesis that these kainate-treated rats consistently develop a chronic epileptic state (i.e. long-term occurrence of spontaneous, generalized seizures and motor convulsions) following a latent period after the initial treatment. Kainate (5 mg/kg per h, i.p.) was administered to rats every hour for several hours so that class III-V seizures were elicited for > or = 3 h, while control rats were treated similarly with saline. This treatment protocol had a relatively low mortality rate (15%). After acute treatment, rats were observed for the occurrence of motor seizures for 6-8 h/week. Nearly all of the kainate-treated rats (97%) had two or more spontaneous motor seizures months after treatment. With this observation protocol, the average latency for the first spontaneous motor seizure was 77+/-38 (+/-S.D.) days after treatment. Although variability was observed between rats, seizure frequency initially increased with time after treatment, and nearly all of the kainate-treated rats (91%) had spontaneous motor seizures until the time of euthanasia (i.e. 5-22 months after treatment). Therefore, multiple low-dose injections of kainate, which cause recurrent motor seizures for > or = 3 h, lead to the development of a chronic epileptic state that is characterized by (i) a latent period before the onset of chronic motor seizures, and (ii) a high but variable seizure frequency that initially increases with time after the first chronic seizure. This modification of the kainate-treatment protocol is efficient and relatively simple, and the properties of the chronic epileptic state appear similar to severe human temporal lobe epilepsy. Furthermore, the observation that seizure frequency initially increased as a function of time after kainate treatment supports the hypothesis that temporal lobe epilepsy can be a progressive syndrome.

Multiple transient memories in sheared suspensions: Robustness, structure, and routes to plasticity

NASA Astrophysics Data System (ADS)

Keim, Nathan C.; Paulsen, Joseph D.; Nagel, Sidney R.

2013-09-01

Multiple transient memories, originally discovered in charge-density-wave conductors, are a remarkable and initially counterintuitive example of how a system can store information about its driving. In this class of memories, a system can learn multiple driving inputs, nearly all of which are eventually forgotten despite their continual input. If sufficient noise is present, the system regains plasticity so that it can continue to learn new memories indefinitely. Recently, Keim and Nagel [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.010603 107, 010603 (2011)] showed how multiple transient memories could be generalized to a generic driven disordered system with noise, giving as an example simulations of a simple model of a sheared non-Brownian suspension. Here, we further explore simulation models of suspensions under cyclic shear, focusing on three main themes: robustness, structure, and overdriving. We show that multiple transient memories are a robust feature independent of many details of the model. The steady-state spatial distribution of the particles is sensitive to the driving algorithm; nonetheless, the memory formation is independent of such a change in particle correlations. Finally, we demonstrate that overdriving provides another means for controlling memory formation and retention.

Comparing State-Space Multivariable Controls to Multi-SISO Controls for Load Reduction of Drivetrain-Coupled Modes on Wind Turbines Through Field-Testing

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

Fleming, P. A.; Van Wingerden, J. W.; Wright, A. D.

2012-01-01

In this paper we present results from an ongoing controller comparison study at the National Renewable Energy Laboratory's (NREL's) National Wind Technology Center (NWTC). The intention of the study is to demonstrate the advantage of using modern multivariable methods for designing control systems for wind turbines versus conventional approaches. We will demonstrate the advantages through field-test results from experimental turbines located at the NWTC. At least two controllers are being developed side-by-side to meet an incrementally increasing number of turbine load-reduction objectives. The first, a multiple single-input, single-output (m-SISO) approach, uses separately developed decoupled and classicially tuned controllers, which is,more » to the best of our knowledge, common practice in the wind industry. The remaining controllers are developed using state-space multiple-input and multiple-output (MIMO) techniques to explicity account for coupling between loops and to optimize given known frequency structures of the turbine and disturbance. In this first publication from the study, we present the structure of the ongoing controller comparison experiment, the design process for the two controllers compared in this phase, and initial comparison results obtained in field-testing.« less

Modeling the Potential Effects of New Tobacco Products and Policies. A Dynamic Population Model for Multiple Product Use and Harm

DOE PAGES

Vugrin, Eric D.; Rostron, Brian L.; Verzi, Stephen J.; ...

2015-03-27

Background Recent declines in US cigarette smoking prevalence have coincided with increases in use of other tobacco products. Multiple product tobacco models can help assess the population health impacts associated with use of a wide range of tobacco products. Methods and Findings We present a multi-state, dynamical systems population structure model that can be used to assess the effects of tobacco product use behaviors on population health. The model incorporates transition behaviors, such as initiation, cessation, switching, and dual use, related to the use of multiple products. The model tracks product use prevalence and mortality attributable to tobacco use formore » the overall population and by sex and age group. The model can also be used to estimate differences in these outcomes between scenarios by varying input parameter values. We demonstrate model capabilities by projecting future cigarette smoking prevalence and smoking-attributable mortality and then simulating the effects of introduction of a hypothetical new lower-risk tobacco product under a variety of assumptions about product use. Sensitivity analyses were conducted to examine the range of population impacts that could occur due to differences in input values for product use and risk. We demonstrate that potential benefits from cigarette smokers switching to the lower-risk product can be offset over time through increased initiation of this product. Model results show that population health benefits are particularly sensitive to product risks and initiation, switching, and dual use behaviors. Conclusion Our model incorporates the variety of tobacco use behaviors and risks that occur with multiple products. As such, it can evaluate the population health impacts associated with the introduction of new tobacco products or policies that may result in product switching or dual use. Further model development will include refinement of data inputs for non-cigarette tobacco products and inclusion of health outcomes such as morbidity and disability.« less

Modeling the Potential Effects of New Tobacco Products and Policies: A Dynamic Population Model for Multiple Product Use and Harm

PubMed Central

Vugrin, Eric D.; Rostron, Brian L.; Verzi, Stephen J.; Brodsky, Nancy S.; Brown, Theresa J.; Choiniere, Conrad J.; Coleman, Blair N.; Paredes, Antonio; Apelberg, Benjamin J.

2015-01-01

Background Recent declines in US cigarette smoking prevalence have coincided with increases in use of other tobacco products. Multiple product tobacco models can help assess the population health impacts associated with use of a wide range of tobacco products. Methods and Findings We present a multi-state, dynamical systems population structure model that can be used to assess the effects of tobacco product use behaviors on population health. The model incorporates transition behaviors, such as initiation, cessation, switching, and dual use, related to the use of multiple products. The model tracks product use prevalence and mortality attributable to tobacco use for the overall population and by sex and age group. The model can also be used to estimate differences in these outcomes between scenarios by varying input parameter values. We demonstrate model capabilities by projecting future cigarette smoking prevalence and smoking-attributable mortality and then simulating the effects of introduction of a hypothetical new lower-risk tobacco product under a variety of assumptions about product use. Sensitivity analyses were conducted to examine the range of population impacts that could occur due to differences in input values for product use and risk. We demonstrate that potential benefits from cigarette smokers switching to the lower-risk product can be offset over time through increased initiation of this product. Model results show that population health benefits are particularly sensitive to product risks and initiation, switching, and dual use behaviors. Conclusion Our model incorporates the variety of tobacco use behaviors and risks that occur with multiple products. As such, it can evaluate the population health impacts associated with the introduction of new tobacco products or policies that may result in product switching or dual use. Further model development will include refinement of data inputs for non-cigarette tobacco products and inclusion of health outcomes such as morbidity and disability. PMID:25815840

Modeling the potential effects of new tobacco products and policies: a dynamic population model for multiple product use and harm.

PubMed

Vugrin, Eric D; Rostron, Brian L; Verzi, Stephen J; Brodsky, Nancy S; Brown, Theresa J; Choiniere, Conrad J; Coleman, Blair N; Paredes, Antonio; Apelberg, Benjamin J

2015-01-01

Recent declines in US cigarette smoking prevalence have coincided with increases in use of other tobacco products. Multiple product tobacco models can help assess the population health impacts associated with use of a wide range of tobacco products. We present a multi-state, dynamical systems population structure model that can be used to assess the effects of tobacco product use behaviors on population health. The model incorporates transition behaviors, such as initiation, cessation, switching, and dual use, related to the use of multiple products. The model tracks product use prevalence and mortality attributable to tobacco use for the overall population and by sex and age group. The model can also be used to estimate differences in these outcomes between scenarios by varying input parameter values. We demonstrate model capabilities by projecting future cigarette smoking prevalence and smoking-attributable mortality and then simulating the effects of introduction of a hypothetical new lower-risk tobacco product under a variety of assumptions about product use. Sensitivity analyses were conducted to examine the range of population impacts that could occur due to differences in input values for product use and risk. We demonstrate that potential benefits from cigarette smokers switching to the lower-risk product can be offset over time through increased initiation of this product. Model results show that population health benefits are particularly sensitive to product risks and initiation, switching, and dual use behaviors. Our model incorporates the variety of tobacco use behaviors and risks that occur with multiple products. As such, it can evaluate the population health impacts associated with the introduction of new tobacco products or policies that may result in product switching or dual use. Further model development will include refinement of data inputs for non-cigarette tobacco products and inclusion of health outcomes such as morbidity and disability.

Modeling the Potential Effects of New Tobacco Products and Policies. A Dynamic Population Model for Multiple Product Use and Harm

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

Vugrin, Eric D.; Rostron, Brian L.; Verzi, Stephen J.

Background Recent declines in US cigarette smoking prevalence have coincided with increases in use of other tobacco products. Multiple product tobacco models can help assess the population health impacts associated with use of a wide range of tobacco products. Methods and Findings We present a multi-state, dynamical systems population structure model that can be used to assess the effects of tobacco product use behaviors on population health. The model incorporates transition behaviors, such as initiation, cessation, switching, and dual use, related to the use of multiple products. The model tracks product use prevalence and mortality attributable to tobacco use formore » the overall population and by sex and age group. The model can also be used to estimate differences in these outcomes between scenarios by varying input parameter values. We demonstrate model capabilities by projecting future cigarette smoking prevalence and smoking-attributable mortality and then simulating the effects of introduction of a hypothetical new lower-risk tobacco product under a variety of assumptions about product use. Sensitivity analyses were conducted to examine the range of population impacts that could occur due to differences in input values for product use and risk. We demonstrate that potential benefits from cigarette smokers switching to the lower-risk product can be offset over time through increased initiation of this product. Model results show that population health benefits are particularly sensitive to product risks and initiation, switching, and dual use behaviors. Conclusion Our model incorporates the variety of tobacco use behaviors and risks that occur with multiple products. As such, it can evaluate the population health impacts associated with the introduction of new tobacco products or policies that may result in product switching or dual use. Further model development will include refinement of data inputs for non-cigarette tobacco products and inclusion of health outcomes such as morbidity and disability.« less

Big data on a big new market: Insights from Washington State's legal cannabis market.

PubMed

Caulkins, Jonathan P; Bao, Yilun; Davenport, Steve; Fahli, Imane; Guo, Yutian; Kinnard, Krista; Najewicz, Mary; Renaud, Lauren; Kilmer, Beau

2018-07-01

Voters in eight U.S. states have passed initiatives to legalize large-scale commercial production of cannabis for non-medical use. All plan or require some form of "seed-to-sale" tracking systems, which provide a view of cannabis market activity at a heretofore unimagined level of detail. Legal markets also create a range of new matters for policy makers to address. Publicly available data were obtained on approximately 45 million individually priced items purchased in the 35 million retail transactions that took place during the first two and a half years of Washington State's legal cannabis market. Records include product type (flower, extract, lotion, liquid edible, etc.), product name, price, and potency with respect to multiple cannabinoids, notably THC and CBD. Items sold can be traced back up the supply chain through the store to the processor and producer, to the level of identifying the specific production batch and mother plant, the firm that tested the product, and test results. Data visualization methods are employed to describe spatial-temporal patterns of multiple correlated attributes (e.g., price and potency) broken down by product. Text-analytic methods are used to subdivide the broad category of "extracts for inhalation" into more homogeneous sub-categories. To understand the competitiveness of the legal cannabis market in Washington we calculate the Herfindahl-Hirschman index (HHI) for processors and retailers. Cannabis prices fell steadily and proportionally at the processor and retailer levels. Retail and wholesale price maintained a roughly 3:1 ratio for multiple product types after some initial fluctuations. Although a wide range of edibles are sold, they account for a modest share of consumer spending; extracts for inhalation are a larger and heterogeneous market segment. The HHI indicates the cannabis market is highly competitive at the processor level, but less so for retail markets at the county level. Washington's state-legal cannabis market is diverse and rapidly evolving in terms of pricing, products, and organization. Post-legalization, researchers and policy makers may need to think in terms of a family of cannabis products, akin to how we think of new psychoactive substances and amphetamine-type stimulants, not a single drug "cannabis." Copyright © 2018 Elsevier B.V. All rights reserved.

An equation-free approach to agent-based computation: Bifurcation analysis and control of stationary states

NASA Astrophysics Data System (ADS)

Siettos, C. I.; Gear, C. W.; Kevrekidis, I. G.

2012-08-01

We show how the equation-free approach can be exploited to enable agent-based simulators to perform system-level computations such as bifurcation, stability analysis and controller design. We illustrate these tasks through an event-driven agent-based model describing the dynamic behaviour of many interacting investors in the presence of mimesis. Using short bursts of appropriately initialized runs of the detailed, agent-based simulator, we construct the coarse-grained bifurcation diagram of the (expected) density of agents and investigate the stability of its multiple solution branches. When the mimetic coupling between agents becomes strong enough, the stable stationary state loses its stability at a coarse turning point bifurcation. We also demonstrate how the framework can be used to design a wash-out dynamic controller that stabilizes open-loop unstable stationary states even under model uncertainty.

Mathematical modeling of solid cancer growth with angiogenesis

PubMed Central

2012-01-01

Background Cancer arises when within a single cell multiple malfunctions of control systems occur, which are, broadly, the system that promote cell growth and the system that protect against erratic growth. Additional systems within the cell must be corrupted so that a cancer cell, to form a mass of any real size, produces substances that promote the growth of new blood vessels. Multiple mutations are required before a normal cell can become a cancer cell by corruption of multiple growth-promoting systems. Methods We develop a simple mathematical model to describe the solid cancer growth dynamics inducing angiogenesis in the absence of cancer controlling mechanisms. Results The initial conditions supplied to the dynamical system consist of a perturbation in form of pulse: The origin of cancer cells from normal cells of an organ of human body. Thresholds of interacting parameters were obtained from the steady states analysis. The existence of two equilibrium points determine the strong dependency of dynamical trajectories on the initial conditions. The thresholds can be used to control cancer. Conclusions Cancer can be settled in an organ if the following combination matches: better fitness of cancer cells, decrease in the efficiency of the repairing systems, increase in the capacity of sprouting from existing vascularization, and higher capacity of mounting up new vascularization. However, we show that cancer is rarely induced in organs (or tissues) displaying an efficient (numerically and functionally) reparative or regenerative mechanism. PMID:22300422

Spin-locking of half-integer quadrupolar nuclei in nuclear magnetic resonance of solids: creation and evolution of coherences.

PubMed

Ashbrook, Sharon E; Wimperis, Stephen

2004-02-08

Spin-locking of half-integer quadrupolar nuclei, such as 23Na (I=3/2) and 27Al (I=5/2), is of renewed interest owing to the development of variants of the multiple-quantum and satellite-transition magic angle spinning (MAS) nuclear magnetic resonance experiments that either utilize spin-locking directly or offer the possibility that spin-locked states may arise. However, the large magnitude and, under MAS, the time dependence of the quadrupolar interaction often result in complex spin-locking phenomena that are not widely understood. Here we show that, following the application of a spin-locking pulse, a variety of coherence transfer processes occur on a time scale of approximately 1/omegaQ before the spin system settles down into a spin-locked state which may itself be time dependent if MAS is performed. We show theoretically for both spin I=3/2 and 5/2 nuclei that the spin-locked state created by this initial rapid dephasing typically consists of a variety of single- and multiple-quantum coherences and nonequilibrium population states and we discuss the subsequent evolution of these under MAS. In contrast to previous work, we consider spin-locking using a wide range of radio frequency field strengths, i.e., a range that covers both the "strong-field" (omega1 > omegaQPAS and "weak-field" (omega1 < omegaQPAS limits. Single- and multiple-quantum filtered spin-locking experiments on NaNO2, NaNO3, and Al(acac)3, under both static and MAS conditions, are used to illustrate and confirm the results of the theoretical discussion.

Ethylene Glycol Quenching of Nitrogenase Catalysis: An Electron Paramagnetic Resonance Spectroscopic Study of Nitrogenase Turnover States and CO Bonding.

PubMed

Hales, Brian J

2015-07-14

Most hydrophilic organic solvents inhibit enzymatic activity. Nitrogenase is shown to be approximately 3 times more sensitive to organic inhibition than most other soluble enzymes. Ethylene glycol (EG) is demonstrated to rapidly inhibit nitrogenase activity without uncoupling ATP hydrolysis. Our data suggest the mechanism of inhibition is EG's blocking of binding of MgATP to the nitrogenase Fe protein. EG quenching allows, for the first time, the observation of the relaxation of the intermediate reaction states at room temperature. Electron paramagnetic resonance (EPR) spectroscopy is used to monitor the room-temperature decay of the nitrogenase turnover states following EG quenching of catalytic activity. The return of the intermediate states to the resting state occurs in multiple phases over 2 h. During the initial stage, nitrogenase still possesses the ability to generate CO-induced EPR signals even though catalytic activity has ceased. During the last phase of relaxation, the one-electron reduced state of the MoFe protein (E1) relaxes to the resting state (E0) in a slow first-order reaction.

Signatures of α clustering in ultrarelativistic collisions with light nuclei

NASA Astrophysics Data System (ADS)

Rybczyński, Maciej; Piotrowska, Milena; Broniowski, Wojciech

2018-03-01

We explore possible observable signatures of α clustering of light nuclei in ultrarelativistic nuclear collisions involving Be,97, 12C, and 16O. The clustering leads to specific spatial correlations of the nucleon distributions in the ground state, which are manifest in the earliest stage of the ultrahigh energy reaction. The formed initial state of the fireball is sensitive to these correlations, and the effect influences, after the collective evolution of the system, the hadron production in the final stage. Specifically, we study effects on the harmonic flow in collisions of light clustered nuclei with a heavy target (208Pb), showing that measures of the elliptic flow are sensitive to clusterization in Be,97, whereas triangular flow is sensitive to clusterization in 12C and 16O. Specific predictions are made for model collisions at energies available at the CERN Super Proton Synchrotron. In another exploratory development we also examine proton-beryllium collisions, where the 3 /2- ground state of Be,97 nuclei is polarized by an external magnetic field. Clusterization leads to multiplicity distributions of participant nucleons which depend on the orientation of the polarization with respect to the collision axis, as well as on the magnetic number of the state. The obtained effects on multiplicities reach a factor of a few for collisions with a large number of participant nucleons.

Experiments on Thermal Convection in Rotating Spherical Shells With Radial Gravity: The Geophysical Fluid Flow Cell

NASA Technical Reports Server (NTRS)

Hart, John E.

1996-01-01

Experiments designed to study the fluid dynamics of buoyancy driven circulations in rotating spherical shells were conducted on the United States Microgravity Laboratory 2 spacelab mission. These experiments address several aspects of prototypical global convection relevant to large scale motions on the Sun, Earth, and on the giant planets. The key feature is the consistent modeling of radially directed gravity in spherical geometry by using dielectric polarization forces. Imagery of the planforms of thermally driven flows for rapidly-rotating regimes shows an initial separation and eventual merger of equatorial and polar convection as the heating (i.e. the Rayleigh number) is increased. At low rotation rates, multiple-states of motion for the same external parameters were observed.

Initiation of Detonation in Multiple Shock-Compressed Liquid Explosives

NASA Astrophysics Data System (ADS)

Yoshinaka, A. C.; Zhang, F.; Petel, O. E.; Higgins, A. J.

2006-07-01

Initiation and resulting propagation of detonation via multiple shock reverberations between two high impedance plates has been investigated in amine-sensitized nitromethane. Experiments were designed so that the first reflected shock strength was below the critical value for initiation found previously. Luminosity combined with a distinct pressure hump indicated onset of reaction and successful initiation after double or triple shock reflection off the bottom plate. Final temperature estimates for double or triple shock reflection immediately before initiation lie between 700-720 K, consistent with those found previously for both incident and singly reflected shock initiation.

Carrier transport in amorphous silicon utilizing picosecond photoconductivity

NASA Astrophysics Data System (ADS)

Johnson, A. M.

1981-08-01

The development of a high-speed electronic measurement capability permitted the direct observation of the transient photoresponse of amorphous silicon (a-Si) with a time resolution of approximately 10ps. This technique was used to measure the initial mobility of photogenerated (2.1eV) free carriers in three types of a-Si having widely different densities of structural defects (i.e., as prepared by: (1) RF glow discharge (a-Si:H); (2) chemical vapor deposition; and (3) evaporation in ultra-high vacuum). In all three types of a-Si, the same initial mobility of approximately 1 cu cm/Vs at room temperature was found. This result tends to confirm the often-made suggestion that the free carrier mobility is determined by the influence of shallow states associated with the disorder in the random atomic network, and is an intrinsic property of a-Si which is unaffected by the method of preparation. The rate of decay of the photocurrent correlates with the density of structural defects and varies from 4ps to 200ps for the three types of a-Si investigated. The initial mobility of a-Si:H was found to be thermally activated. The possible application of extended state transport controlled by multiple trapping and small polaron formation is discussed.

Atmospheric Ascent Guidance for Rocket-Powered Launch Vehicles

NASA Technical Reports Server (NTRS)

Dukeman, Greg A.

2002-01-01

An advanced ascent guidance algorithm for rocket- powered launch vehicles is developed. This algorithm cyclically solves the calculus-of-variations two-point boundary-value problem starting at vertical rise completion through main engine cutoff. This is different from traditional ascent guidance algorithms which operate in a simple open-loop mode until high dynamic pressure (including the critical max-Q) portion of the trajectory is over, at which time guidance operates under the assumption of negligible aerodynamic acceleration (i.e., vacuum dynamics). The initial costate guess is corrected based on errors in the terminal state constraints and the transversality conditions. Judicious approximations are made to reduce the order and complexity of the state/costate system. Results comparing guided launch vehicle trajectories with POST open-loop trajectories are given verifying the basic formulation of the algorithm. Multiple shooting is shown to be a very effective numerical technique for this application. In particular, just one intermediate shooting point, in addition to the initial shooting point, is sufficient to significantly reduce sensitivity to the guessed initial costates. Simulation results from a high-fidelity trajectory simulation are given for the case of launch to sub-orbital cutoff conditions as well as launch to orbit conditions. An abort to downrange landing site formulation of the algorithm is presented.

Solution of linear systems by a singular perturbation technique

NASA Technical Reports Server (NTRS)

Ardema, M. D.

1976-01-01

An approximate solution is obtained for a singularly perturbed system of initial valued, time invariant, linear differential equations with multiple boundary layers. Conditions are stated under which the approximate solution converges uniformly to the exact solution as the perturbation parameter tends to zero. The solution is obtained by the method of matched asymptotic expansions. Use of the results for obtaining approximate solutions of general linear systems is discussed. An example is considered to illustrate the method and it is shown that the formulas derived give a readily computed uniform approximation.

The Canadian Hydrological Model (CHM): A multi-scale, variable-complexity hydrological model for cold regions

NASA Astrophysics Data System (ADS)

Marsh, C.; Pomeroy, J. W.; Wheater, H. S.

2016-12-01

There is a need for hydrological land surface schemes that can link to atmospheric models, provide hydrological prediction at multiple scales and guide the development of multiple objective water predictive systems. Distributed raster-based models suffer from an overrepresentation of topography, leading to wasted computational effort that increases uncertainty due to greater numbers of parameters and initial conditions. The Canadian Hydrological Model (CHM) is a modular, multiphysics, spatially distributed modelling framework designed for representing hydrological processes, including those that operate in cold-regions. Unstructured meshes permit variable spatial resolution, allowing coarse resolutions at low spatial variability and fine resolutions as required. Model uncertainty is reduced by lessening the necessary computational elements relative to high-resolution rasters. CHM uses a novel multi-objective approach for unstructured triangular mesh generation that fulfills hydrologically important constraints (e.g., basin boundaries, water bodies, soil classification, land cover, elevation, and slope/aspect). This provides an efficient spatial representation of parameters and initial conditions, as well as well-formed and well-graded triangles that are suitable for numerical discretization. CHM uses high-quality open source libraries and high performance computing paradigms to provide a framework that allows for integrating current state-of-the-art process algorithms. The impact of changes to model structure, including individual algorithms, parameters, initial conditions, driving meteorology, and spatial/temporal discretization can be easily tested. Initial testing of CHM compared spatial scales and model complexity for a spring melt period at a sub-arctic mountain basin. The meshing algorithm reduced the total number of computational elements and preserved the spatial heterogeneity of predictions.

Artery of Percheron: an unusual stroke presentation.

PubMed

Pitts-Tucker, Toby; Small, Jeremy

2018-03-28

An 86-year-old woman was admitted with multiple episodes of transient loss of consciousness. She was initially treated for seizures, and stroke was not considered likely. MRI on the same day of admission showed acute bilateral medial thalamic infarcts in keeping with the Artery of Percheron (AOP) territory infarcts. Investigation for polycythaemia and thrombocytosis showed JAK2 positive myeloproliferative neoplasm.A diagnosis of AOP infarction is often missed or delayed because it is rare and presents with variable neurological symptoms. Initial imaging in the form of CT is often negative, and some report that initial MRI findings may also be normal.An awareness of a wide range of differential diagnoses alongside a multi-modality imaging approach is required to reach a diagnosis.Although there are several other case reports of AOP infarction in the literature, this is the first to present with transient symptoms initially mistaken for seizure activity. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Choosing Wisely: A Neurosurgical Perspective on Neuroimaging for Headaches

PubMed Central

Hawasli, Ammar H.; Chicoine, Michael R.; Dacey, Ralph G.

2016-01-01

Multiple national initiatives seek to curb spending in order to address increasing health care costs in the United States. The Choosing Wisely® initiative is one popular initiative that focuses on reducing health care spending by setting guidelines to limit tests and procedures requested by patients and ordered by physicians. To reduce spending on neuroimaging, the Choosing Wisely® initiative and other organizations have offered guidelines to limit neuroimaging for headaches. Although the intentions are laudable, these guidelines are inconsistent with the neurosurgeon’s experience with brain tumor patients. If adopted by governing or funding organizations, these guidelines threaten to negatively impact the care and outcomes of patients with brain tumors, who frequently present with minimal symptoms or isolated headaches syndromes. As we grapple with the difficult conflict between evidence-based cost-cutting guidelines and individualized patient-tailored medicine, a physician must carefully balance the costs and benefits of discretionary services such as neuroimaging for headaches. By participating in the development of validated clinical decision rules on neuroimaging for headaches, neurosurgeons can advocate for their patients and improve their patients’ outcomes. PMID:25255253

The Jormungand Global Climate State and Implications for the Neoproterozoic Snowball Paradox (Invited)

NASA Astrophysics Data System (ADS)

Abbot, D. S.; Voigt, A.; Koll, D.; Pierrehumbert, R. T.

2010-12-01

We present a previously undescribed global climate state, the Jormungand state, that is nearly ice-covered with a narrow (~10-15 degrees of latitude) strip of open ocean near the equator. This state is sustained by internal dynamics of the hydrological cycle and the cryosphere. There is a new bifurcation in global climate climate associated with the Jormungand state that leads to significant hysteresis. We investigate the Jormungand state in a coupled ocean-atmosphere GCM, in multiple atmospheric GCMs coupled to a mixed layer ocean run in an idealized configuration, and we make a simple modification to the Budyko-Sellers model so that it produces Jormungand states. We suggest that the Jormungand state may be a better model for the Neoproterozoic glaciations (~635 Ma and ~715 Ma) than either the hard Snowball or the Slushball models. A Jormungand state would have a large enough region of open ocean near the equator to explain the micropaleontological and molecular clock evidence that photosynthetic eukaryotes thrived both before and immediately after the Neoproterozoic episodes. Additionally, since there is significant hysteresis associated with the Jormungand state, it can explain the cap carbonate sequences, the oxygen isotopic evidence that suggests high CO2 values, and the various evidence that suggests lifetimes for the glaciations of 1 Myrs or more. Since there is not significant hysteresis associated with the Slushball model, the Slushball model cannot explain these observations. Finally, we note that although the Slushball and Jormungand models share the characteristic of open ocean in the tropics, the Jormungand state is produced by entirely different physics, is entered through a new bifurcation in global climate, and is associated with significant hysteresis. Bifurcation diagram of global climate in the CAM global climate model, run with no continents, a 50 m mixed layer with no ocean heat transport, an eccentricity of zero, and annually and diurnally-varying insolation with a solar constant of 94% of present value. Red diamonds denote simulations initiated from ice-free conditions, blue circles denote simulations initiated from the Jormungand state, and green squares denote simulations initiated from the Snowball state. The black curve shows model equilibria, with dotted unstable solution branches (separatrices) and bifurcations drawn schematically.

The network of corporate clients: customer attrition at commercial banks

NASA Astrophysics Data System (ADS)

Lublóy, Á.; Szenes, M.

2008-12-01

Commercial banks might profit from the adoption of methods widely used in network theory. A decision making process might become biased if one disregards network effects within the corporate client portfolio. This paper models the phenomenon of customer attrition by generating a weighted and directed network of corporate clients linked by financial transactions. During the numerical study of the agent-based toy model we demonstrate that multiple steady states may exist. The statistical properties of the distinct steady states show similarities. We show that most companies of the same community choose the same bank in the steady state. In contrast to the case for the steady state of the Barabási-Albert network, market shares in this model equalize by network size. When modeling customer attrition in the network of 3 × 105 corporate clients, none of the companies followed the behavior of the initial switcher in three quarters of the simulations. The number of switchers exceeded 20 in 1% of the cases. In the worst-case scenario a total of 688 companies chose a competitor bank. Significant network effects have been discovered; high correlation prevailed between the degree of the initial switcher and the severity of the avalanche effect. This suggests that the position of the corporate client in the network might be much more important than the underlying properties (industry, size, profitability, etc) of the company.

A brief introduction to PYTHIA 8.1

NASA Astrophysics Data System (ADS)

Sjöstrand, Torbjörn; Mrenna, Stephen; Skands, Peter

2008-06-01

The PYTHIA program is a standard tool for the generation of high-energy collisions, comprising a coherent set of physics models for the evolution from a few-body hard process to a complex multihadronic final state. It contains a library of hard processes and models for initial- and final-state parton showers, multiple parton-parton interactions, beam remnants, string fragmentation and particle decays. It also has a set of utilities and interfaces to external programs. While previous versions were written in Fortran, PYTHIA 8 represents a complete rewrite in C++. The current release is the first main one after this transition, and does not yet in every respect replace the old code. It does contain some new physics aspects, on the other hand, that should make it an attractive option especially for LHC physics studies. Program summaryProgram title:PYTHIA 8.1 Catalogue identifier: ACTU_v3_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ACTU_v3_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GPL version 2 No. of lines in distributed program, including test data, etc.: 176 981 No. of bytes in distributed program, including test data, etc.: 2 411 876 Distribution format: tar.gz Programming language: C++ Computer: Commodity PCs Operating system: Linux; should also work on other systems RAM: 8 megabytes Classification: 11.2 Does the new version supersede the previous version?: yes, partly Nature of problem: High-energy collisions between elementary particles normally give rise to complex final states, with large multiplicities of hadrons, leptons, photons and neutrinos. The relation between these final states and the underlying physics description is not a simple one, for two main reasons. Firstly, we do not even in principle have a complete understanding of the physics. Secondly, any analytical approach is made intractable by the large multiplicities. Solution method: Complete events are generated by Monte Carlo methods. The complexity is mastered by a subdivision of the full problem into a set of simpler separate tasks. All main aspects of the events are simulated, such as hard-process selection, initial- and final-state radiation, beam remnants, fragmentation, decays, and so on. Therefore events should be directly comparable with experimentally observable ones. The programs can be used to extract physics from comparisons with existing data, or to study physics at future experiments. Reasons for new version: Improved and expanded physics models, transition from Fortran to C++. Summary of revisions: New user interface, transverse-momentum-ordered showers, interleaving with multiple interactions, and much more. Restrictions: Depends on the problem studied. Running time: 10-1000 events per second, depending on process studied. References: [1] T. Sjöstrand, P. Edén, C. Friberg, L. Lönnblad, G. Miu, S. Mrenna, E. Norrbin, Comput. Phys. Comm. 135 (2001) 238.

Theoretically informed Monte Carlo simulation of liquid crystals by sampling of alignment-tensor fields.

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

Armas-Perez, Julio C.; Londono-Hurtado, Alejandro; Guzman, Orlando

2015-07-27

A theoretically informed coarse-grained Monte Carlo method is proposed for studying liquid crystals. The free energy functional of the system is described in the framework of the Landau-de Gennes formalism. The alignment field and its gradients are approximated by finite differences, and the free energy is minimized through a stochastic sampling technique. The validity of the proposed method is established by comparing the results of the proposed approach to those of traditional free energy minimization techniques. Its usefulness is illustrated in the context of three systems, namely, a nematic liquid crystal confined in a slit channel, a nematic liquid crystalmore » droplet, and a chiral liquid crystal in the bulk. It is found that for systems that exhibit multiple metastable morphologies, the proposed Monte Carlo method is generally able to identify lower free energy states that are often missed by traditional approaches. Importantly, the Monte Carlo method identifies such states from random initial configurations, thereby obviating the need for educated initial guesses that can be difficult to formulate.« less

Theoretically informed Monte Carlo simulation of liquid crystals by sampling of alignment-tensor fields

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

Armas-Pérez, Julio C.; Londono-Hurtado, Alejandro; Guzmán, Orlando

2015-07-28

A theoretically informed coarse-grained Monte Carlo method is proposed for studying liquid crystals. The free energy functional of the system is described in the framework of the Landau-de Gennes formalism. The alignment field and its gradients are approximated by finite differences, and the free energy is minimized through a stochastic sampling technique. The validity of the proposed method is established by comparing the results of the proposed approach to those of traditional free energy minimization techniques. Its usefulness is illustrated in the context of three systems, namely, a nematic liquid crystal confined in a slit channel, a nematic liquid crystalmore » droplet, and a chiral liquid crystal in the bulk. It is found that for systems that exhibit multiple metastable morphologies, the proposed Monte Carlo method is generally able to identify lower free energy states that are often missed by traditional approaches. Importantly, the Monte Carlo method identifies such states from random initial configurations, thereby obviating the need for educated initial guesses that can be difficult to formulate.« less

Genomic epidemiology reveals multiple introductions of Zika virus into the United States

PubMed Central

Grubaugh, Nathan D; Ladner, Jason T; Kraemer, Moritz UG; Dudas, Gytis; Tan, Amanda L; Gangavarapu, Karthik; Wiley, Michael R; White, Stephen; Thézé, Julien; Magnani, Diogo M; Prieto, Karla; Reyes, Daniel; Bingham, Andrea; Paul, Lauren M; Robles-Sikisaka, Refugio; Oliveira, Glenn; Pronty, Darryl; Barcellona, Carolyn M; Metsky, Hayden C; Baniecki, Mary Lynn; Barnes, Kayla G; Chak, Bridget; Freije, Catherine A; Gladden-Young, Adrianne; Gnirke, Andreas; Luo, Cynthia; MacInnis, Bronwyn; Matranga, Christian B; Park, Daniel J; Qu, James; Schaffner, Stephen F; Tomkins-Tinch, Christopher; West, Kendra L; Winnicki, Sarah M; Wohl, Shirlee; Yozwiak, Nathan L; Quick, Joshua; Fauver, Joseph R; Khan, Kamran; Brent, Shannon E; Reiner, Robert C; Lichtenberger, Paola N; Ricciardi, Michael; Bailey, Varian K; Watkins, David I; Cone, Marshall R; Kopp, Edgar W; Hogan, Kelly N; Cannons, Andrew C; Jean, Reynald; Monaghan, Andrew J; Garry, Robert F; Loman, Nicholas J; Faria, Nuno R; Porcelli, Mario C; Vasquez, Chalmers; Nagle, Elyse R; Cummings, Derek AT; Stanek, Danielle; Rambaut, Andrew; Sanchez-Lockhart, Mariano; Sabeti, Pardis C; Gillis, Leah D; Michael, Scott F; Bedford, Trevor; Pybus, Oliver G; Isern, Sharon; Palacios, Gustavo; Andersen, Kristian G

2017-01-01

Zika virus (ZIKV) is causing an unprecedented epidemic linked to severe congenital syndromes1,2. In July 2016, mosquito-borne ZIKV transmission was reported in the continental United States and since then, hundreds of locally-acquired infections have been reported in Florida3,4. To gain insights into the timing, source, and likely route(s) of ZIKV introduction, we tracked the virus from its first detection in Florida by sequencing ZIKV genomes from infected patients and Aedes aegypti mosquitoes. We show that at least four introductions, but potentially as many as 40, contributed to the outbreak in Florida and that local transmission likely started in the spring of 2016 - several months before initial detection. By analyzing surveillance and genetic data, we discovered that ZIKV moved among transmission zones in Miami. Our analyses show that most introductions are linked to the Caribbean, a finding corroborated by the high incidence rates and traffic volumes from the region into the Miami area. Our study provides an understanding of how ZIKV initiates transmission in new regions. PMID:28538723

Analysis of damaging process and crack propagation

NASA Astrophysics Data System (ADS)

Semenski, D.; Wolf, H.; Božić, Ž.

2010-06-01

Supervising and health monitoring of structures can assess the actual state of existing structures after initial loading or in the state of operation. Structural life management requires the integration of design and analysis, materials behavior and structural testing, as given for several examples. Procedure of survey of structural elements and criteria for their selection must be strongly defined as it is for the offshore gas platforms. Numerical analysis of dynamic loading is shown for the Aeolian vibrations of overhead transmission line conductors. Since the damper’s efficiency strongly depends on its position, the procedure of determining the optimum position of the damper is described. The optical method of caustics is established in isotropic materials for determination of the stress intensity factors (SIFs) of the cracks in deformed structures and is advantageously improved for the application to fiberreinforced composites. A procedure for simulation of crack propagation for multiple cracks was introduced and SIFs have been calculated by using finite element method. Crack growth of a single crack or a periodical array of cracks initiated at the stiffeners in a stiffened panel has been investigated.

Genomic epidemiology reveals multiple introductions of Zika virus into the United States

NASA Astrophysics Data System (ADS)

Grubaugh, Nathan D.; Ladner, Jason T.; Kraemer, Moritz U. G.; Dudas, Gytis; Tan, Amanda L.; Gangavarapu, Karthik; Wiley, Michael R.; White, Stephen; Thézé, Julien; Magnani, Diogo M.; Prieto, Karla; Reyes, Daniel; Bingham, Andrea M.; Paul, Lauren M.; Robles-Sikisaka, Refugio; Oliveira, Glenn; Pronty, Darryl; Barcellona, Carolyn M.; Metsky, Hayden C.; Baniecki, Mary Lynn; Barnes, Kayla G.; Chak, Bridget; Freije, Catherine A.; Gladden-Young, Adrianne; Gnirke, Andreas; Luo, Cynthia; Macinnis, Bronwyn; Matranga, Christian B.; Park, Daniel J.; Qu, James; Schaffner, Stephen F.; Tomkins-Tinch, Christopher; West, Kendra L.; Winnicki, Sarah M.; Wohl, Shirlee; Yozwiak, Nathan L.; Quick, Joshua; Fauver, Joseph R.; Khan, Kamran; Brent, Shannon E.; Reiner, Robert C.; Lichtenberger, Paola N.; Ricciardi, Michael J.; Bailey, Varian K.; Watkins, David I.; Cone, Marshall R.; Kopp, Edgar W.; Hogan, Kelly N.; Cannons, Andrew C.; Jean, Reynald; Monaghan, Andrew J.; Garry, Robert F.; Loman, Nicholas J.; Faria, Nuno R.; Porcelli, Mario C.; Vasquez, Chalmers; Nagle, Elyse R.; Cummings, Derek A. T.; Stanek, Danielle; Rambaut, Andrew; Sanchez-Lockhart, Mariano; Sabeti, Pardis C.; Gillis, Leah D.; Michael, Scott F.; Bedford, Trevor; Pybus, Oliver G.; Isern, Sharon; Palacios, Gustavo; Andersen, Kristian G.

2017-06-01

Zika virus (ZIKV) is causing an unprecedented epidemic linked to severe congenital abnormalities. In July 2016, mosquito-borne ZIKV transmission was reported in the continental United States; since then, hundreds of locally acquired infections have been reported in Florida. To gain insights into the timing, source, and likely route(s) of ZIKV introduction, we tracked the virus from its first detection in Florida by sequencing ZIKV genomes from infected patients and Aedes aegypti mosquitoes. We show that at least 4 introductions, but potentially as many as 40, contributed to the outbreak in Florida and that local transmission is likely to have started in the spring of 2016—several months before its initial detection. By analysing surveillance and genetic data, we show that ZIKV moved among transmission zones in Miami. Our analyses show that most introductions were linked to the Caribbean, a finding corroborated by the high incidence rates and traffic volumes from the region into the Miami area. Our study provides an understanding of how ZIKV initiates transmission in new regions.

Relaxation and thermalization in the one-dimensional Bose-Hubbard model: A case study for the interaction quantum quench from the atomic limit

NASA Astrophysics Data System (ADS)

Heidrich-Meisner, Fabian; Pollet, Lode; Sorg, Stefan; Vidmar, Lev

2015-03-01

We study the relaxation dynamics and thermalization in the one-dimensional Bose-Hubbard model induced by a global interaction quench. Specifically, we start from an initial state that has exactly one boson per site and is the ground state of a system with infinitely strong repulsive interactions at unit filling. The same interaction quench was realized in a recent experiment. Using exact diagonalization and the density-matrix renormalization-group method, we compute the time dependence of such observables as the multiple occupancy and the momentum distribution function. We discuss our numerical results in the framework of the eigenstate thermalization hypothesis and we observe that the microcanonical ensemble describes the time averages of many observables reasonably well for small and intermediate interaction strength. Moreover, the diagonal and the canonical ensembles are practically identical for our initial conditions already on the level of their respective energy distributions for small interaction strengths. Supported by the DFG through FOR 801 and the Alexander von Humboldt foundation.

Combining remote sensing and watershed modeling for regional-scale carbon cycling studies in disturbance-prone systems

NASA Astrophysics Data System (ADS)

Hanan, E. J.; Tague, C.; Choate, J.; Liu, M.; Adam, J. C.

2016-12-01

Disturbance is a major force regulating C dynamics in terrestrial ecosystems. Evaluating future C balance in disturbance-prone systems requires understanding the underlying mechanisms that drive ecosystem processes over multiple scales of space and time. Simulation modeling is a powerful tool for bridging these scales, however, model projections are limited by large uncertainties in the initial state of vegetation C and N stores. Watershed models typically use one of two methods to initialize these stores. Spin up involves running a model until vegetation reaches steady state based on climate. This "potential" state however assumes the vegetation across the entire watershed has reached maturity and has a homogeneous age distribution. Yet to reliably represent C and N dynamics in disturbance-prone systems, models should be initialized to reflect their non-equilibrium conditions. Alternatively, remote sensing of a single vegetation parameter (typically leaf area index; LAI) can be combined with allometric relationships to allocate C and N to model stores and can reflect non-steady-state conditions. However, allometric relationships are species and region specific and do not account for environmental variation, thus resulting in C and N stores that may be unstable. To address this problem, we developed a new approach for initializing C and N pools using the watershed-scale ecohydrologic model RHESSys. The new approach merges the mechanistic stability of spinup with the spatial fidelity of remote sensing. Unlike traditional spin up, this approach supports non-homogeneous stand ages. We tested our approach in a pine-dominated watershed in central Idaho, which partially burned in July of 2000. We used LANDSAT and MODIS data to calculate LAI across the watershed following the 2000 fire. We then ran three sets of simulations using spin up, direct measurements, and the combined approach to initialize vegetation C and N stores, and compared our results to remotely sensed LAI following the simulation period. Model estimates of C, N, and water fluxes varied depending on which approach was used. The combined approach provided the best LAI estimates after 10 years of simulation. This method shows promise for improving projections of C, N, and water fluxes in disturbance-prone watersheds.

Atypical anticipatory postural adjustments during gait initiation among individuals with sub-acute stroke.

PubMed

Rajachandrakumar, Roshanth; Fraser, Julia E; Schinkel-Ivy, Alison; Inness, Elizabeth L; Biasin, Lou; Brunton, Karen; McIlroy, William E; Mansfield, Avril

2017-02-01

Anticipatory postural adjustments, executed prior to gait initiation, help preserve lateral stability when stepping. Atypical patterns of anticipatory activity prior to gait initiation may occur in individuals with unilateral impairment (e.g., stroke). This study aimed to determine the prevalence, correlates, and consequences of atypical anticipatory postural adjustment patterns prior to gait initiation in a sub-acute stroke population. Forty independently-ambulatory individuals with sub-acute stroke stood on two force plates and initiated gait at a self-selected speed. Medio-lateral centre of pressure displacement was calculated and used to define anticipatory postural adjustments (shift in medio-lateral centre of pressure >10mm from baseline). Stroke severity, motor recovery, and functional balance and mobility status were also obtained. Three patterns were identified: single (typical), absent (atypical), and multiple (atypical) anticipatory postural adjustments. Thirty-five percent of trials had atypical anticipatory postural adjustments (absent and multiple). Frequency of absent anticipatory postural adjustments was negatively correlated with walking speed. Multiple anticipatory postural adjustments were more prevalent when leading with the non-paretic than the paretic limb. Trials with multiple anticipatory postural adjustments had longer duration of anticipatory postural adjustment and time to foot-off, and shorter unloading time than trials with single anticipatory postural adjustments. A high prevalence of atypical anticipatory control prior to gait initiation was found in individuals with stroke. Temporal differences were identified with multiple anticipatory postural adjustments, indicating altered gait initiation. These findings provide insight into postural control during gait initiation in individuals with sub-acute stroke, and may inform interventions to improve ambulation in this population. Copyright © 2016 Elsevier B.V. All rights reserved.

Endogenous Thrombin Potential Changes during the First Cycle of Oral Contraceptive Use

PubMed Central

Westhoff, Carolyn L.; Pike, Malcolm C.; Cremers, Serge; Eisenberger, Andrew; Thomassen, Stella; Rosing, Jan

2017-01-01

Objectives Venous thromboembolism (VTE) risk increases within months of combination oral contraceptive (COC) initiation. Because elevated endogenous thrombin potential (ETP) has been found in several studies to be a VTE risk factor, we evaluated the extent of ETP changes during the initial cycle of an ethinyl estradiol (EE) and levonorgestrel (LNG) COC. We also assessed the relationship between ETP changes and systemic EE and LNG concentrations. Study Design Participants provided multiple blood samples during a first 21-day cycle of a 30 µg EE/150 µg LNG COC and after a further 7 days without an active COC. Thrombin generation measured with and without addition of activated protein C (APC) yielded ETP+APC and ETP−APC and the normalized APC sensitivity ratio (nAPCsr). EE and LNG pharmacokinetic analyses were conducted over 24 hours after the first COC tablet and again at steady state. Results Thrombin generation was determined in 16 of the 17 women who completed the study. Mean ETP−APC increased steadily to 21% above baseline at 24 hours after the 6th COC tablet (COC624; p < 0.001) and to 28% above baseline at steady state (COC21; p < 0.001). Mean ETP+APC increased considerably more – by 54% at COC624 and by 79% at steady state. Mean nAPCsr increased by 28% at COC624 and by 41% at steady state. Higher concentrations of EE or LNG were not correlated with greater increases in ETP. Conclusions ETP increases during the first COC cycle were substantial. Implications The early increases in ETP may provide biological support for the rapid increase in VTE risk during initial COC use. The lack of association between this clotting system perturbation and the systemic EE concentration is surprising and deserves further study. PMID:28088496

Advances in using Internet searches to track dengue

PubMed Central

Yang, Shihao; Kou, Samuel C.; Brownstein, John S.; Brooke, Nicholas

2017-01-01

Dengue is a mosquito-borne disease that threatens over half of the world’s population. Despite being endemic to more than 100 countries, government-led efforts and tools for timely identification and tracking of new infections are still lacking in many affected areas. Multiple methodologies that leverage the use of Internet-based data sources have been proposed as a way to complement dengue surveillance efforts. Among these, dengue-related Google search trends have been shown to correlate with dengue activity. We extend a methodological framework, initially proposed and validated for flu surveillance, to produce near real-time estimates of dengue cases in five countries/states: Mexico, Brazil, Thailand, Singapore and Taiwan. Our result shows that our modeling framework can be used to improve the tracking of dengue activity in multiple locations around the world. PMID:28727821

Non Secretory Multiple Myeloma With Extensive Extramedullary Plasmacytoma: A Diagnostic Dilemma

PubMed Central

Low, Soo Fin; Mohd Tap, Nor Hanani; Kew, Thean Yean; Ngiu, Chai Soon; Sridharan, Radhika

2015-01-01

Multiple myeloma (MM) is characterized by progressive proliferation of malignant plasma cells, usually initiating in the bone marrow. MM can affect any organ; a total of 7 - 18% of patients with MM demonstrate extramedullary involvement at diagnosis. Non-secretory multiple myeloma (NSMM) is a rare variant that accounts for 1 - 5% of all cases of multiple myeloma. The disease is characterized by the absence of monoclonal gammopathy in serum and urine electrophoresis. Our case report highlights the diagnostic challenge of a case of NSMM with extensive extramedullary involvement in a young female patient who initially presented with right shoulder pain and bilateral breasts lumps. Skeletal survey showed multiple lytic bony lesions. The initial diagnosis was primary breast carcinoma with osseous metastases. No monoclonal gammopathy was found in the serum or urine electrophoresis. Bone marrow and breast biopsies revealed marked plasmacytosis. The diagnosis was delayed for a month in view of the lack of clinical suspicion of multiple myeloma in a young patient and scant biochemical expression of non-secretory type of multiple myeloma. PMID:26528383

Dynamic optimization and adaptive controller design

NASA Astrophysics Data System (ADS)

Inamdar, S. R.

2010-10-01

In this work I present a new type of controller which is an adaptive tracking controller which employs dynamic optimization for optimizing current value of controller action for the temperature control of nonisothermal continuously stirred tank reactor (CSTR). We begin with a two-state model of nonisothermal CSTR which are mass and heat balance equations and then add cooling system dynamics to eliminate input multiplicity. The initial design value is obtained using local stability of steady states where approach temperature for cooling action is specified as a steady state and a design specification. Later we make a correction in the dynamics where material balance is manipulated to use feed concentration as a system parameter as an adaptive control measure in order to avoid actuator saturation for the main control loop. The analysis leading to design of dynamic optimization based parameter adaptive controller is presented. The important component of this mathematical framework is reference trajectory generation to form an adaptive control measure.

Enhancing Pediatric Palliative Care for Latino Children and Their Families: A Review of the Literature and Recommendations for Research and Practice in the United States

PubMed Central

Raisanen, Jessica C.; Donohue, Pamela K.; Boss, Renee D.

2017-01-01

As the demand for pediatric palliative care (PC) increases, data suggest that Latino children are less likely to receive services than non-Latino children. Evidence on how to best provide PC to Latino children is sparse. We conducted a narrative review of literature related to PC for Latino children and their families in the United States. In the United States, Latinos face multiple barriers that affect their receipt of PC, including poverty, lack of access to health insurance, language barriers, discrimination, and cultural differences. Pediatric PC research and clinical initiatives that target the needs of Latino families are sparse, underfunded, but essential. Education of providers on Latino cultural values is necessary. Additionally, advocacy efforts with a focus on equitable care and policy reform are essential to improving the health of this vulnerable population. PMID:29271924

Water state changes during the composting of kitchen waste.

PubMed

Shen, Dong-Sheng; Yang, Yu-Qiang; Huang, Huan-Lin; Hu, Li-Fang; Long, Yu-Yang

2015-04-01

Changes in water states during the composting of kitchen waste were determined. Three experiments, R(55), R(60), and R(65), with different initial moisture contents, 55%, 60%, and 65%, respectively, were performed. Three water states, entrapped water (EW), capillary water (CW), and multiple-molecular-layer water (MMLW), were monitored during the experiments. Changes only occurred with the EW and CW during the composting process. The percentage of EW increased, and the percentage of CW decreased as the composting process progressed. The R(60) experiment performed better than the other experiments according to changes in the temperature and carbon-to-nitrogen ratio (C/N). The percentage of EW correlated well (P<0.05) with the dissolved organic carbon content (DOC), electrical conductivity (EC), pH, and C/N, and was affected by the hemicellulose and cellulose contents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Psychological Factors and Alcohol Use in Problematic Mobile Phone Use in the Spanish Population

PubMed Central

De-Sola, José; Talledo, Hernán; Rubio, Gabriel; de Fonseca, Fernando Rodríguez

2017-01-01

This research aims to study the existing relationships among the factors of state anxiety, depression, impulsivity, and alcohol consumption regarding problematic mobile phone use, as assessed by the Mobile Phone Problem Use Scale. The study was conducted among 1,126 participants recruited among the general Spanish population, aged 16–65 years, by assessing the predictive value of these variables regarding this problematic use. Initially tobacco use was also considered being subsequently refused because of the low internal consistency of the scale used. In general terms, the results show that this problematic use is mainly related to state anxiety and impulsivity, through the dimensions of Positive and Negative Urgency. Considering its predictive value, multiple regression analysis reveals that state anxiety, positive and negative urgency, and alcohol consumption may predict problematic mobile phone use, ruling out the influence of depression. PMID:28217101

Generation of steady entanglement via unilateral qubit driving in bad cavities.

PubMed

Jin, Zhao; Su, Shi-Lei; Zhu, Ai-Dong; Wang, Hong-Fu; Shen, Li-Tuo; Zhang, Shou

2017-12-15

We propose a scheme for generating an entangled state for two atoms trapped in two separate cavities coupled to each other. The scheme is based on the competition between the unitary dynamics induced by the classical fields and the collective decays induced by the dissipation of two non-local bosonic modes. In this scheme, only one qubit is driven by external classical fields, whereas the other need not be manipulated via classical driving. This is meaningful for experimental implementation between separate nodes of a quantum network. The steady entanglement can be obtained regardless of the initial state, and the robustness of the scheme against parameter fluctuations is numerically demonstrated. We also give an analytical derivation of the stationary fidelity to enable a discussion of the validity of this regime. Furthermore, based on the dissipative entanglement preparation scheme, we construct a quantum state transfer setup with multiple nodes as a practical application.

Psychological Factors and Alcohol Use in Problematic Mobile Phone Use in the Spanish Population.

PubMed

De-Sola, José; Talledo, Hernán; Rubio, Gabriel; de Fonseca, Fernando Rodríguez

2017-01-01

This research aims to study the existing relationships among the factors of state anxiety, depression, impulsivity, and alcohol consumption regarding problematic mobile phone use, as assessed by the Mobile Phone Problem Use Scale. The study was conducted among 1,126 participants recruited among the general Spanish population, aged 16-65 years, by assessing the predictive value of these variables regarding this problematic use. Initially tobacco use was also considered being subsequently refused because of the low internal consistency of the scale used. In general terms, the results show that this problematic use is mainly related to state anxiety and impulsivity, through the dimensions of Positive and Negative Urgency. Considering its predictive value, multiple regression analysis reveals that state anxiety, positive and negative urgency, and alcohol consumption may predict problematic mobile phone use, ruling out the influence of depression.

Pausing controls branching between productive and non-productive pathways during initial transcription in bacteria.

PubMed

Dulin, David; Bauer, David L V; Malinen, Anssi M; Bakermans, Jacob J W; Kaller, Martin; Morichaud, Zakia; Petushkov, Ivan; Depken, Martin; Brodolin, Konstantin; Kulbachinskiy, Andrey; Kapanidis, Achillefs N

2018-04-16

Transcription in bacteria is controlled by multiple molecular mechanisms that precisely regulate gene expression. It has been recently shown that initial RNA synthesis by the bacterial RNA polymerase (RNAP) is interrupted by pauses; however, the pausing determinants and the relationship of pausing with productive and abortive RNA synthesis remain poorly understood. Using single-molecule FRET and biochemical analysis, here we show that the pause encountered by RNAP after the synthesis of a 6-nt RNA (ITC6) renders the promoter escape strongly dependent on the NTP concentration. Mechanistically, the paused ITC6 acts as a checkpoint that directs RNAP to one of three competing pathways: productive transcription, abortive RNA release, or a new unscrunching/scrunching pathway. The cyclic unscrunching/scrunching of the promoter generates a long-lived, RNA-bound paused state; the abortive RNA release and DNA unscrunching are thus not as tightly linked as previously thought. Finally, our new model couples the pausing with the abortive and productive outcomes of initial transcription.

Combat Wound Initiative program.

PubMed

Stojadinovic, Alexander; Elster, Eric; Potter, Benjamin K; Davis, Thomas A; Tadaki, Doug K; Brown, Trevor S; Ahlers, Stephen; Attinger, Christopher E; Andersen, Romney C; Burris, David; Centeno, Jose; Champion, Hunter; Crumbley, David R; Denobile, John; Duga, Michael; Dunne, James R; Eberhardt, John; Ennis, William J; Forsberg, Jonathan A; Hawksworth, Jason; Helling, Thomas S; Lazarus, Gerald S; Milner, Stephen M; Mullick, Florabel G; Owner, Christopher R; Pasquina, Paul F; Patel, Chirag R; Peoples, George E; Nissan, Aviram; Ring, Michael; Sandberg, Glenn D; Schaden, Wolfgang; Schultz, Gregory S; Scofield, Tom; Shawen, Scott B; Sheppard, Forest R; Stannard, James P; Weina, Peter J; Zenilman, Jonathan M

2010-07-01

The Combat Wound Initiative (CWI) program is a collaborative, multidisciplinary, and interservice public-private partnership that provides personalized, state-of-the-art, and complex wound care via targeted clinical and translational research. The CWI uses a bench-to-bedside approach to translational research, including the rapid development of a human extracorporeal shock wave therapy (ESWT) study in complex wounds after establishing the potential efficacy, biologic mechanisms, and safety of this treatment modality in a murine model. Additional clinical trials include the prospective use of clinical data, serum and wound biomarkers, and wound gene expression profiles to predict wound healing/failure and additional clinical patient outcomes following combat-related trauma. These clinical research data are analyzed using machine-based learning algorithms to develop predictive treatment models to guide clinical decision-making. Future CWI directions include additional clinical trials and study centers and the refinement and deployment of our genetically driven, personalized medicine initiative to provide patient-specific care across multiple medical disciplines, with an emphasis on combat casualty care.

Compression of thick laminated composite beams with initial impact-like damage

NASA Technical Reports Server (NTRS)

Breivik, N. L.; Guerdal, Z.; Griffin, O. H., Jr.

1992-01-01

While the study of compression after impact of laminated composites has been under consideration for many years, the complexity of the damage initiated by low velocity impact has not lent itself to simple predictive models for compression strength. The damage modes due to non-penetrating, low velocity impact by large diameter objects can be simulated using quasi-static three-point bending. The resulting damage modes are less coupled and more easily characterized than actual impact damage modes. This study includes the compression testing of specimens with well documented initial damage states obtained from three-point bend testing. Compression strengths and failure modes were obtained for quasi-isotropic stacking sequences from 0.24 to 1.1 inches thick with both grouped and interspersed ply stacking. Initial damage prior to compression testing was divided into four classifications based on the type, extent, and location of the damage. These classifications are multiple through-thickness delaminations, isolated delamination, damage near the surface, and matrix cracks. Specimens from each classification were compared to specimens tested without initial damage in order to determine the effects of the initial damage on the final compression strength and failure modes. A finite element analysis was used to aid in the understanding and explanation of the experimental results.

Public Perceptions of Self-Harm: Perceived Motivations of (and Willingness to Help in Response to) Adolescent Self-Harm.

PubMed

Nielsen, Emma; Townsend, Ellen

2018-01-01

We investigated public perceptions of, and responses to, adolescent self-harm-an under-researched topic, given that the majority of self-harm in this group is not disclosed to formal support services. Participants (N = 355, aged 18-67 years) were presented with 1 of 10 vignettes and completed self-report measures assessing perceived motivations for self-harm and helping/rejecting responses. Vignettes were manipulated across conditions for stated motivation, controllability of stated cause, and presentation format. Results indicate that stated motivation for self-harm, controllability of stated cause, and presentation format affect perceived motivations. Further, participants demonstrate an understanding of the complex nature of self-harm, indicating an appreciation that an individual may hold multiple motivations simultaneously. Perceived motivations for self-harm are associated with the endorsement of helping/rejecting behaviors. These relationships are important to explore, given the critical importance of initial responses to self-harm on subsequent disclosures and help-seeking.

Long-term treatment with low dose naltrexone maintains stable health in patients with multiple sclerosis.

PubMed

Ludwig, Michael D; Turel, Anthony P; Zagon, Ian S; McLaughlin, Patricia J

2016-01-01

A retrospective study was conducted on patients at Penn State Hershey Medical Center diagnosed with relapsing-remitting multiple sclerosis between 2006 and 2015. Laboratory and clinical data collected over this 10-year period were reviewed. Two cohorts of patients were established based on their relapsing-remitting multiple sclerosis therapy at the time of their first visit to Penn State. One group of patients ( n  = 23) was initially prescribed low dose naltrexone at the time first seen at Hershey. This group was offered low dose naltrexone because of symptoms of fatigue or refusal to take an available disease-modifying therapy. The second group of patients ( n  = 31) was treated with the glatiramer acetate (Copaxone) and offered low dose naltrexone as an adjunct therapy to their disease-modifying therapy. Patient data from visits after 1-50 months post-diagnosis were evaluated in a retrospective manner. Data obtained from patient charts included clinical laboratory values from standard blood tests, timed 25-foot walking trials, and changes in magnetic resonance imaging reports. Statistical analyses between the groups and for each patient over time indicated no significant differences in clinical laboratory values, timed walking, or changes in magnetic resonance imaging. These data suggest that the apparently non-toxic, inexpensive, biotherapeutic is safe and if taken alone did not result in an exacerbation of disease symptoms.

Pharmacokinetics of isotretinoin during repetitive dosing to patients.

PubMed

Brazzell, R K; Vane, F M; Ehmann, C W; Colburn, W A

1983-01-01

The multiple dose pharmacokinetics of isotretinoin and its major blood metabolite, 4-oxo-isotretinoin, were studied in 10 patients with cystic acne and 11 patients with various keratinization disorders. Blood samples were obtained at predetermined times following the first dose, interim doses and the final dose. Blood concentrations of isotretinoin and 4-oxo-isotretinoin were measured by a specific and sensitive HPLC method. A lag time was usually observed prior to the onset of absorption following oral administration of the drug in a soft elastic gelatin capsule. Absorption then proceeded rapidly and maximum blood concentrations usually occurred within 4 h of drug administration. The harmonic mean half-life for the elimination of isotretinoin by the cystic acne patients was approximately 10 h after the initial dose and did not change significantly following 25 days of 40 mg b.i.d. dosing. Steady-state blood concentrations remained relatively constant after the fifth day of dosing. The harmonic mean elimination half-life in the patients with various disorders of keratinization was about 16 h. The results of the 2 studies suggest that no significant changes in the pharmacokinetics of isotretinoin occur during multiple dosing and that the multiple dose pharmacokinetic profile is predictable and can be described using a linear pharmacokinetic model. This suggests that the steady-state concentrations of isotretinoin can be predicted from single dose data.

New Contemporary Criterion-Referenced Assessment Instruments for Astronomy & Geology: TOAST & EGGS

NASA Astrophysics Data System (ADS)

Guffey, Sarah Katie; Slater, Stephanie J.; Slater, Timothy F.

2015-08-01

Considerable effort in the astronomy and Earth sciences education research over the past decade has focused on developing assessment tools in the form of multiple-choice conceptual diagnostics and content knowledge surveys. This has been critically important in advancing discipline-based education research allowing scholar to establish the initial, incoming knowledge state of students as well as to attempt to measure some of the impacts of innovative instructional interventions. Before now, few of the existing instruments were constructed upon a solid list of clearly articulated and widely agreed upon learning objectives. Whereas first-generation assessment tools, such as the Astronomy Diagnostics Test ADT2) were based primarily upon further identifying documented astronomy misconceptions, scholars from the CAPER Center for Astronomy & Physics Education Research team are creating contemporary instruments based instead by developing items using modern test construction techniques and tightly aligned to the consensus learning goals identified by the American Association of the Advancement of Science’s Project 2061 Benchmarks, and the National Research Council’s National Science Education Standards, and the National Research Council’s Frameworks for A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. These consensus learning goals are further enhanced guiding documents from the American Astronomical Society - Chair’s Conference on ASTRO 101 and the NSF-funded Earth Science Literacy Initiative. Two of the resulting criterion-referenced assessment tools widely used by researchers are the Test Of Astronomy STandards (TOAST) and the Exam of GeoloGy StandardS (EGGS). These easy-to-use and easy-to-score multiple-choice instruments have a high degree of reliability and validity for instructors and researchers needing information on students’ initial knowledge state at the beginning of a course and can be used, in aggregate, to help measure the impact teaching innovations with learning goals tightly aligned to consensus goals of the broader education community.

End of FY10 report - used fuel disposition technical bases and lessons learned : legal and regulatory framework for high-level waste disposition in the United States.

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

Weiner, Ruth F.; Blink, James A.; Rechard, Robert Paul

This report examines the current policy, legal, and regulatory framework pertaining to used nuclear fuel and high level waste management in the United States. The goal is to identify potential changes that if made could add flexibility and possibly improve the chances of successfully implementing technical aspects of a nuclear waste policy. Experience suggests that the regulatory framework should be established prior to initiating future repository development. Concerning specifics of the regulatory framework, reasonable expectation as the standard of proof was successfully implemented and could be retained in the future; yet, the current classification system for radioactive waste, including hazardousmore » constituents, warrants reexamination. Whether or not consideration of multiple sites are considered simultaneously in the future, inclusion of mechanisms such as deliberate use of performance assessment to manage site characterization would be wise. Because of experience gained here and abroad, diversity of geologic media is not particularly necessary as a criterion in site selection guidelines for multiple sites. Stepwise development of the repository program that includes flexibility also warrants serious consideration. Furthermore, integration of the waste management system from storage, transportation, and disposition, should be examined and would be facilitated by integration of the legal and regulatory framework. Finally, in order to enhance acceptability of future repository development, the national policy should be cognizant of those policy and technical attributes that enhance initial acceptance, and those policy and technical attributes that maintain and broaden credibility.« less

Anxiety, Depression, and Cigarette Smoking: A Transdiagnostic Vulnerability Framework to Understanding Emotion-Smoking Comorbidity

PubMed Central

Leventhal, Adam M.; Zvolensky, Michael J.

2014-01-01

Research into the comorbidity between emotional psychopathology and cigarette smoking has often focused upon anxiety and depression’s manifest symptoms and syndromes, with limited theoretical and clinical advancement. This paper presents a novel framework to understanding emotion-smoking comorbidity. We propose that transdiagnostic emotional vulnerabilities—core biobehavioral traits reflecting maladaptive responses to emotional states that underpin multiple types of emotional psychopathology—link various anxiety and depressive psychopathologies to smoking. This framework is applied in a review and synthesis of the empirical literature on three trandiagnostic emotional vulnerabilities implicated in smoking: (1) anhedonia (Anh; diminished pleasure/interest in response to rewards); (2) anxiety sensitivity (AS; fear of anxiety-related sensations); and (3) distress tolerance (DT; ability to withstand distressing states). We conclude that Anh, AS, and DT collectively: (a) underpin multiple emotional psychopathologies; (b) amplify smoking’s anticipated and actual affect enhancing properties and other mechanisms underlying smoking; (c) promote progression across the smoking trajectory (i.e., initiation, escalation/progression, maintenance, cessation/relapse); and (d) are promising targets for smoking intervention. After existing gaps are identified, an integrative model of transdiagnostic processes linking emotional psychopathology to smoking is proposed. The model’s key premise is that Anh amplifies smoking’s anticipated and actual pleasure-enhancing effects, AS amplifies smoking’s anxiolytic effects, and poor DT amplifies smoking’s distress terminating effects. Collectively, these processes augment the reinforcing properties of smoking for individuals with emotional psychopathology to heighten risk of smoking initiation, progression, maintenance, cessation avoidance, and relapse. We conclude by drawing clinical and scientific implications from this framework that may generalize to other comorbidities. PMID:25365764

Vesicular erythema migrans: an atypical and easily misdiagnosed form of Lyme disease.

PubMed

Mazori, Daniel R; Orme, Charisse M; Mir, Adnan; Meehan, Shane A; Neimann, Andrea L

2015-08-15

Erythema migrans is the initial sign in the majority of patients infected with Borrelia, the genus of spirochetes that causes Lyme disease. Early identification and treatment decrease the risk of progression to later stages of disease. Although a "bull's eye" appearance owing to lesional clearing is considered classic for erythema migrans, this feature is surprisingly often lacking among patients in the United States. Furthermore, cutaneous Lyme disease can exhibit a wide range of morphologic variability in a minority of patients. Herein, we describe the case of a patient with Lyme disease in which the presence of atypical vesicular features, in conjunction with the initial absence of clearing, resulted in multiple misdiagnoses and delayed treatment. We also review the literature on the epidemiology and management of erythema migrans for cases in which the diagnosis may pose a challenge.

Implementing Health and Safety Policy Changes at the High School Level From a Leadership Perspective.

PubMed

Pagnotta, Kelly D; Mazerolle, Stephanie M; Pitney, William A; Burton, Laura J; Casa, Douglas J

2016-04-01

Although consensus statements and recommendations from professional organizations aim to reduce the incidence of injury or sudden death in sport, nothing is mandated at the high school level. This allows states the freedom to create and implement individual policies. An example of a recommended policy is heat acclimatization. Despite its efficacy in reducing sudden death related to heat stroke, very few states follow the recommended guidelines. To retroactively examine why and how 3 states were able to facilitate the successful creation and adoption of heat-acclimatization guidelines. Qualitative study. High school athletic associations in Arkansas, Georgia, and New Jersey. Eight men and 3 women (n = 11; 6 athletic trainers; 2 members of high school athletic associations; 2 parents; 1 physician) participated. Participant recruitment ceased when data saturation was reached. All phone interviews were digitally recorded and transcribed verbatim. A grounded-theory approach guided analysis and multiple analysts and peer review were used to establish credibility. Each state had a different catalyst to change (student-athlete death, empirical data, proactivity). Recommendations from national governing bodies guided the policy creation. Once the decision to implement change was made, the states displayed 2 similarities: shared leadership and open communication between medical professionals and members of the high school athletic association helped overcome barriers. The initiating factor that spurred the change varied, yet shared leadership and communication fundamentally allowed for successful adoption of the policy. Our participants were influenced by the recommendations from national governing bodies, which align with the institutional change theory. As more states begin to examine and improve their health and safety policies, this information could serve as a valuable resource for athletic trainers in other states and for future health and safety initiatives.

Folding of human telomerase RNA pseudoknot using ion-jump and temperature-quench simulations.

PubMed

Biyun, Shi; Cho, Samuel S; Thirumalai, D

2011-12-21

Globally RNA folding occurs in multiple stages involving chain compaction and subsequent rearrangement by a number of parallel routes to the folded state. However, the sequence-dependent details of the folding pathways and the link between collapse and folding are poorly understood. To obtain a comprehensive picture of the thermodynamics and folding kinetics we used molecular simulations of coarse-grained model of a pseudoknot found in the conserved core domain of the human telomerase (hTR) by varying both temperature (T) and ion concentration (C). The phase diagram in the [T,C] plane shows that the boundary separating the folded and unfolded state for the finite 47-nucleotide system is relatively sharp, implying that from a thermodynamic perspective hTR behaves as an apparent two-state system. However, the folding kinetics following single C-jump or T-quench is complicated, involving multiple channels to the native state. Although globally folding kinetics triggered by T-quench and C-jump are similar, the kinetics of chain compaction are vastly different, which reflects the role of initial conditions in directing folding and collapse. Remarkably, even after substantial reduction in the overall size of hTR, the ensemble of compact conformations are far from being nativelike, suggesting that the search for the folded state occurs among the ensemble of low-energy fluidlike globules. The rate of unfolding, which occurs in a single step, is faster upon C-decrease compared to a jump in temperature. To identify "hidden" states that are visited during the folding process we performed simulations by periodically interrupting the approach to the folded state by lowering C. These simulations show that hTR reaches the folded state through a small number of connected clusters that are repeatedly visited during the pulse sequence in which the folding or unfolding is interrupted. The results from interrupted folding simulations, which are in accord with non-equilibrium single-molecule folding of a large ribozyme, show that multiple probes are needed to reveal the invisible states that are sampled by RNA as it folds. Although we have illustrated the complexity of RNA folding using hTR as a case study, general arguments and qualitative comparisons to time-resolved scattering experiments on Azoarcus group I ribozyme and single-molecule non-equilibrium periodic ion-jump experiments establish the generality of our findings. © 2011 American Chemical Society

Ab initio multiple spawning dynamics study of dimethylnitramine and dimethylnitramine-Fe complex to model their ultrafast nonadiabatic chemistry

NASA Astrophysics Data System (ADS)

Bera, Anupam; Ghosh, Jayanta; Bhattacharya, Atanu

2017-07-01

Conical intersections are now firmly established to be the key features in the excited electronic state processes of polyatomic energetic molecules. In the present work, we have explored conical intersection-mediated nonadiabatic chemical dynamics of a simple analogue nitramine molecule, dimethylnitramine (DMNA, containing one N-NO2 energetic group), and its complex with an iron atom (DMNA-Fe). For this task, we have used the ab initio multiple spawning (AIMS) dynamics simulation at the state averaged-complete active space self-consistent field(8,5)/6-31G(d) level of theory. We have found that DMNA relaxes back to the ground (S0) state following electronic excitation to the S1 excited state [which is an (n,π*) excited state] with a time constant of approximately 40 fs. This AIMS result is in very good agreement with the previous surface hopping-result and femtosecond laser spectroscopy result. DMNA does not dissociate during this fast internal conversion from the S1 to the S0 state. DMNA-Fe also undergoes extremely fast relaxation from the upper S1 state to the S0 state; however, this relaxation pathway is dissociative in nature. DMNA-Fe undergoes initial Fe-O, N-O, and N-N bond dissociations during relaxation from the upper S1 state to the ground S0 state through the respective conical intersection. The AIMS simulation reveals the branching ratio of these three channels as N-N:Fe-O:N-O = 6:3:1 (based on 100 independent simulations). Furthermore, the AIMS simulation reveals that the Fe-O bond dissociation channel exhibits the fastest (time constant 24 fs) relaxation, while the N-N bond dissociation pathway features the slowest (time constant 128 fs) relaxation. An intermediate time constant (30 fs) is found for the N-O bond dissociation channel. This is the first nonadiabatic chemical dynamics study of metal-contained energetic molecules through conical intersections.

Simulations of Karenia Brevis on the West Florida Shelf

NASA Astrophysics Data System (ADS)

Lenes, J. M.; Darrow, B. P.; Chen, F. R.; Walsh, J. J.; Dieterle, D. A.; Weisberg, R. H.

2010-12-01

The ecological model, HABSIM, was developed and tested to examine the initiation and maintenance of red tides of the toxic dinoflagellate Karenia brevis on the West Florida shelf (WFS). Phytoplankton competition among K. brevis, nitrogen fixing cyanophytes (Trichodesmium spp.), large siliceous phytoplankton (diatoms), and small non-siliceous phytoplankton (microflagellates) thus explores the sequence of events required to support the observed bloom from August to December 2001. The ecological model contains twenty two state variables within four submodels: atmospheric (iron deposition), biological (phytoplankton, bacteria, zooplankton, and fish), chemical (multiple species of carbon, nitrogen, phosphorus, silica, and iron), and benthic (nutrient regeneration). Here, we present results for the 2001 1-d hindcast simulations, with and without data assimilation of the Karenia state variable, as well as preliminary 3-d results.

The effects of internal heating and large scale climate variations on tectonic bi-stability in terrestrial planets

NASA Astrophysics Data System (ADS)

Weller, M. B.; Lenardic, A.; O'Neill, C.

2015-06-01

We use 3D mantle convection and planetary tectonics models to explore the links between tectonic regimes and the level of internal heating within the mantle of a planet (a proxy for thermal age), planetary surface temperature, and lithosphere strength. At both high and low values of internal heating, for moderate to high lithospheric yield strength, hot and cold stagnant-lid (single plate planet) states prevail. For intermediate values of internal heating, multiple stable tectonic states can exist. In these regions of parameter space, the specific evolutionary path of the system has a dominant role in determining its tectonic state. For low to moderate lithospheric yield strength, mobile-lid behavior (a plate tectonic-like mode of convection) is attainable for high degrees of internal heating (i.e., early in a planet's thermal evolution). However, this state is sensitive to climate driven changes in surface temperatures. Relatively small increases in surface temperature can be sufficient to usher in a transition from a mobile- to a stagnant-lid regime. Once a stagnant-lid mode is initiated, a return to mobile-lid is not attainable by a reduction of surface temperatures alone. For lower levels of internal heating, the tectonic regime becomes less sensitive to surface temperature changes. Collectively our results indicate that terrestrial planets can alternate between multiple tectonic states over giga-year timescales. Within parameter space regions that allow for bi-stable behavior, any model-based prediction as to the current mode of tectonics is inherently non-unique in the absence of constraints on the geologic and climatic histories of a planet.

Intermittent Drug Dosing Intervals Guided by the Operational Multiple Dosing Half Lives for Predictable Plasma Accumulation and Fluctuation

PubMed Central

Grover, Anita; Benet, Leslie Z.

2013-01-01

Intermittent drug dosing intervals are usually initially guided by the terminal pharmacokinetic half life and are dependent on drug formulation. For chronic multiple dosing and for extended release dosage forms, the terminal half life often does not predict the plasma drug accumulation or fluctuation observed. We define and advance applications for the operational multiple dosing half lives for drug accumulation and fluctuation after multiple oral dosing at steady-state. Using Monte Carlo simulation, our results predict a way to maximize the operational multiple dosing half lives relative to the terminal half life by using a first-order absorption rate constant close to the terminal elimination rate constant in the design of extended release dosage forms. In this way, drugs that may be eliminated early in the development pipeline due to a relatively short half life can be formulated to be dosed at intervals three times the terminal half life, maximizing compliance, while maintaining tight plasma concentration accumulation and fluctuation ranges. We also present situations in which the operational multiple dosing half lives will be especially relevant in the determination of dosing intervals, including for drugs that follow a direct PKPD model and have a narrow therapeutic index, as the rate of concentration decrease after chronic multiple dosing (that is not the terminal half life) can be determined via simulation. These principles are illustrated with case studies on valproic acid, diazepam, and anti-hypertensives. PMID:21499748

Electronic coupling between photo-excited stacked bases in DNA and RNA strands with emphasis on the bright states initially populated.

PubMed

Nielsen, Lisbeth Munksgaard; Hoffmann, Søren Vrønning; Nielsen, Steen Brøndsted

2013-08-01

In biology the interplay between multiple light-absorbers gives rise to complex quantum effects such as superposition states that are of extreme importance for life, both for harvesting solar energy and likely protecting nucleic acids from radiation damage. Still the characteristics of these states and their quantum dynamics are a much debated issue. While the electronic properties of single bases are fairly well understood, the situation for strands is complicated by the fact that stacked bases electronically couple when photoexcited. These newly arising states are denoted as exciton states and are simply linear combinations of localised wavefunctions that involve N - 1 ground-state bases and one base in its excited state (cf. the Frenkel exciton model). There is disagreement over the number of bases, N, that coherently couple, i.e., the spatial extent of the exciton, and how electronic deexcitation back to the ground state occurs. The importance of dark charge-transfer states has been inferred both from time-resolved fluorescence and transient absorption experiments. These states were suggested to be responsible for long deexcitation times but it is unclear whether 'long' is tens of picoseconds or nanoseconds. In this review paper, we focus on the bright states initially populated and discuss their nature based on information obtained from systematic absorption and circular dichroism experiments on single strands of different lengths. Our results from the last five years are compared with those from other groups, and are discussed in the context of successive deexcitation schemes. Pieces to the puzzle have come from different experiments and theory but a complete description has yet to emerge. As such the story about DNA/RNA photophysical decay mechanisms resembles the tale about the blind men and the elephant where all see the beast in different, correct but incomplete ways.

An evaluation of two methods for increasing self-initiated verbalizations in autistic children.

PubMed Central

Matson, J L; Sevin, J A; Box, M L; Francis, K L; Sevin, B M

1993-01-01

Three children with autism and mental retardation were treated for deficits in self-initiated speech. A novel treatment package employing visual cue fading was compared with a graduated time-delay procedure previously shown to be effective for increasing self-initiated language. Both treatments included training multiple self-initiated verbalizations using multiple therapists and settings. Both treatments were effective, with no differences in measures of acquisition of target phrases, maintenance of behavioral gains, acquisition with additional therapists and settings, and social validity. PMID:8407687

Infectious disease and dermatologic conditions in evacuees and rescue workers after Hurricane Katrina--multiple states, August-September, 2005.

PubMed

2005-09-30

On August 29, 2005, Hurricane Katrina struck states along the Gulf Coast of the United States. In the days after the hurricane struck, approximately 750 evacuation centers were established in at least 18 states to accommodate more than 200,000 evacuees. State and local health departments, with assistance from CDC, initiated enhanced infectious disease surveillance and outbreak response activities, implemented by teams of public health and rescue workers, including military personnel. Outbreak monitoring included direct reporting of conditions of public health significance to public health agencies; daily contact between CDC and local public health officials; canvassing of reports from CDC, public health departments, and news media for potential infectious disease outbreaks; and investigation of reports of infectious disease with outbreak potential. This report summarizes infectious disease and dermatologic conditions reported during the first 3 weeks after the hurricane, before effective local surveillance was fully implemented. One outbreak of norovirus was reported among evacuees in Texas; no other outbreaks requiring unusual mobilization of public health resources were reported among evacuees or rescue workers.

Psychophysiological Sensing and State Classification for Attention Management in Commercial Aviation

NASA Technical Reports Server (NTRS)

Harrivel, Angela R.; Liles, Charles; Stephens, Chad L.; Ellis, Kyle K.; Prinzel, Lawrence J.; Pope, Alan T.

2016-01-01

Attention-related human performance limiting states (AHPLS) can cause pilots to lose airplane state awareness (ASA), and their detection is important to improving commercial aviation safety. The Commercial Aviation Safety Team found that the majority of recent international commercial aviation accidents attributable to loss of control inflight involved flight crew loss of airplane state awareness, and that distraction of various forms was involved in all of them. Research on AHPLS, including channelized attention, diverted attention, startle / surprise, and confirmation bias, has been recommended in a Safety Enhancement (SE) entitled "Training for Attention Management." To accomplish the detection of such cognitive and psychophysiological states, a broad suite of sensors has been implemented to simultaneously measure their physiological markers during high fidelity flight simulation human subject studies. Pilot participants were asked to perform benchmark tasks and experimental flight scenarios designed to induce AHPLS. Pattern classification was employed to distinguish the AHPLS induced by the benchmark tasks. Unimodal classification using pre-processed electroencephalography (EEG) signals as input features to extreme gradient boosting, random forest and deep neural network multiclass classifiers was implemented. Multi-modal classification using galvanic skin response (GSR) in addition to the same EEG signals and using the same types of classifiers produced increased accuracy with respect to the unimodal case (90 percent vs. 86 percent), although only via the deep neural network classifier. These initial results are a first step toward the goal of demonstrating simultaneous real time classification of multiple states using multiple sensing modalities in high-fidelity flight simulators. This detection is intended to support and inform training methods under development to mitigate the loss of ASA and thus reduce accidents and incidents.

Repeat workers' compensation claims: risk factors, costs and work disability

PubMed Central

2011-01-01

Background The objective of our study was to describe factors associated with repeat workers' compensation claims and to compare the work disability arising in workers with single and multiple compensation claims. Methods All initial injury claims lodged by persons of working age during a five year period (1996 to 2000) and any repeat claims were extracted from workers' compensation administrative data in the state of Victoria, Australia. Groups of workers with single and multiple claims were identified. Descriptive analysis of claims by affliction, bodily location, industry segment, occupation, employer and workplace was undertaken. Survival analysis determined the impact of these variables on the time between the claims. The economic impact and duration of work incapacity associated with initial and repeat claims was compared between groups. Results 37% of persons with an initial claim lodged a second claim. This group contained a significantly greater proportion of males, were younger and more likely to be employed in manual occupations and high-risk industries than those with single claims. 78% of repeat claims were for a second injury. Duration between the claims was shortest when the working conditions had not changed. The initial claims of repeat claimants resulted in significantly (p < 0.001) lower costs and work disability than the repeat claims. Conclusions A substantial proportion of injured workers experience a second occupational injury or disease. These workers pose a greater economic burden than those with single claims, and also experience a substantially greater cumulative period of work disability. There is potential to reduce the social, health and economic burden of workplace injury by enacting prevention programs targeted at these workers. PMID:21696637

The New Federalism: State Policies Regarding Embryonic Stem Cell Research.

PubMed

Acosta, Nefi D; Golub, Sidney H

2016-09-01

Stem cell policy in the United States is an amalgam of federal and state policies. The scientific development of human pluripotent embryonic stem cells (ESCs) triggered a contentious national stem cell policy debate during the administration of President George W. Bush. The Bush "compromise" that allowed federal funding to study only a very limited number of ESC derived cell lines did not satisfy either the researchers or the patient advocates who saw great medical potential being stifled. Neither more restrictive legislation nor expansion of federal funding proved politically possible and the federal impasse opened the door for a variety of state-based experiments. In 2004, California became the largest and most influential state venture into stem cell research by passing "Prop 71," a voter initiative that created a new stem cell agency and funded it with $3 billion. Several states followed suit with similar programs to protect the right of investigators to do stem cell research and in some cases to invest state funding in such projects. Other states devised legislation to restrict stem cell research and in five states, criminal penalties were included. Thus, the US stem cell policy is a patchwork of multiple, often conflicting, state and federal policies. © 2016 American Society of Law, Medicine & Ethics.

Analysis in Motion Initiative – Summarization Capability

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

Arendt, Dustin; Pirrung, Meg; Jasper, Rob

2017-06-22

Analysts are tasked with integrating information from multiple data sources for important and timely decision making. What if sense making and overall situation awareness could be improved through visualization techniques? The Analysis in Motion initiative is advancing the ability to summarize and abstract multiple streams and static data sources over time.

Multiple Input Sliding Mode Control for Autonomous Diving and Steering of Underwater Vehicles

DTIC Science & Technology

1990-12-01

States Navy B.S., University of Minnesota Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN MECHANICAL...VARIABLES C REAL UCO,UC,VCO,VC REAL TARGET,PSID,DAWAY,ALPHA REAL XD,XD1,XD2,XPOS,XCURRXCTE,YD,YD1,YD2,YPOS,YCU RR,YCTE REAL XDOT,YDOT INTEGER IWAY, INAV C...INVERT THE MASS MATRIX USING IMSL LIBRARY SUBROUTINE CALL LINRG(3,MM,3,MMINV,3) C C INITIALIZE THE COUNTERS C ISCREEN=l INAV =0 IWAY=l IOUT=1 C C OPEN

Extremal values of the sojourn time

NASA Astrophysics Data System (ADS)

Astaburuaga, M. A.; Cortés, V. H.; Duclos, P.

2010-11-01

Consider a self-adjoint operator H on a separable Hilbert space \\ {H} with non-trivial absolutely continuous component. We study the general properties of the real-valued functional, \\tau _{H}(\\psi )=\\int _{{\\ R}}|(e^{-itH}\\psi,\\psi )|^2\\,dt, which in quantum mechanics represents the sojourn time (or life time) of an initial state \\psi \\in \\ {H}. We characterize the critical points of the sojourn time, τX, of the operator multiplication by x in L^2({\\ R}), and prove that it attains a global maximum in the unit sphere of the Sobolev space \\ {W}^{1,2}({\\ R}).

Constraining biosphere CO2 flux at regional scale with WRF-CO2 4DVar assimilation system

NASA Astrophysics Data System (ADS)

Zheng, T.

2017-12-01

The WRF-CO2 4DVar assimilation system is updated to include (1) operators for tower based observations (2) chemistry initial and boundary condition in the state vector (3) mechanism for aggregation from simulation model grid to state vector space. The update system is first tested with synthetic data to ensure its accuracy. The system is then used to test regional scale CO2 inversion at MCI (Midcontinental intensive) sites where CO2 mole fraction data were collected at multiple high towers during 2007-2008. The model domain is set to center on Iowa and include 8 towers within its boundary, and it is of 12x12km horizontal grid spacing. First, the relative impacts of the initial and boundary condition are assessed by the system's adjoint model. This is done with 24, 48, 72 hour time span. Second, we assessed the impacts of the transport error, including the misrepresentation of the boundary layer and cumulus activities. Third, we evaluated the different aggregation approach from the native model grid to the control variables (including scaling factors for flux, initial and boundary conditions). Four, we assessed the inversion performance using CO2 observation with different time-interval, and from different tower levels. We also examined the appropriate treatment of the background and observation error covariance in relation with these varying observation data sets.

"None of the above" as a correct and incorrect alternative on a multiple-choice test: implications for the testing effect.

PubMed

Odegard, Timothy N; Koen, Joshua D

2007-11-01

Both positive and negative testing effects have been demonstrated with a variety of materials and paradigms (Roediger & Karpicke, 2006b). The present series of experiments replicate and extend the research of Roediger and Marsh (2005) with the addition of a "none-of-the-above" response option. Participants (n=32 in both experiments) read a set of passages, took an initial multiple-choice test, completed a filler task, and then completed a final cued-recall test (Experiment 1) or multiple-choice test (Experiment 2). Questions were manipulated on the initial multiple-choice test by adding a "none-of-the-above" response alternative (choice "E") that was incorrect ("E" Incorrect) or correct ("E" Correct). The results from both experiments demonstrated that the positive testing effect was negated when the "none-of-the-above" alternative was the correct response on the initial multiple-choice test, but was still present when the "none-of-the-above" alternative was an incorrect response.

Multi-specie isothermal flow calculations of widely-spaced co-axial jets in a confined sudden expansion, with the central jet dominant

NASA Astrophysics Data System (ADS)

Sturgess, G. J.; Syed, S. A.

1982-06-01

A numerical simulation is made of the flow in the Wright Aeronautical Propulsion Laboratory diffusion flame research combustor operating with a strong central jet of carbon dioxide in a weak and removed co-axial jet of air. The simulation is based on a finite difference solution of the time-average, steady-state, elliptic form of the Reynolds equations. Closure for these equations is provided by a two-equation turbulence model. Comparisons between measurements and predictions are made for centerline axial velocities and radial profiles of CO2 concentration. Earlier findings for a single specie, constant density, single jet flow that a large expansion ratio confined jet behaves initially as if it were unconfined, are confirmed for the multiple-specie, variable density, multiple-jet system. The lack of universality in the turbulence model constants and the turbulent Schmidt/Prandtl number is discussed.

Brownian Dynamics and Molecular Dynamics Study of the Association between Hydrogenase and Ferredoxin from Chlamydomonas reinhardtii

PubMed Central

Long, Hai; Chang, Christopher H.; King, Paul W.; Ghirardi, Maria L.; Kim, Kwiseon

2008-01-01

The [FeFe] hydrogenase from the green alga Chlamydomonas reinhardtii can catalyze the reduction of protons to hydrogen gas using electrons supplied from photosystem I and transferred via ferredoxin. To better understand the association of the hydrogenase and the ferredoxin, we have simulated the process over multiple timescales. A Brownian dynamics simulation method gave an initial thorough sampling of the rigid-body translational and rotational phase spaces, and the resulting trajectories were used to compute the occupancy and free-energy landscapes. Several important hydrogenase-ferredoxin encounter complexes were identified from this analysis, which were then individually simulated using atomistic molecular dynamics to provide more details of the hydrogenase and ferredoxin interaction. The ferredoxin appeared to form reasonable complexes with the hydrogenase in multiple orientations, some of which were good candidates for inclusion in a transition state ensemble of configurations for electron transfer. PMID:18621810

A model for making project funding decisions at the National Cancer Institute.

PubMed

Hall, N G; Hershey, J C; Kessler, L G; Stotts, R C

1992-01-01

This paper describes the development of a model for making project funding decisions at The National Cancer Institute (NCI). The American Stop Smoking Intervention Study (ASSIST) is a multiple-year, multiple-site demonstration project, aimed at reducing smoking prevalence. The initial request for ASSIST proposals was answered by about twice as many states as could be funded. Scientific peer review of the proposals was the primary criterion used for funding decisions. However, a modified Delphi process made explicit several criteria of secondary importance. A structured questionnaire identified the relative importance of these secondary criteria, some of which we incorporated into a composite preference function. We modeled the proposal funding decision as a zero-one program, and adjusted the preference function and available budget parametrically to generate many suitable outcomes. The actual funding decision, identified by our model, offers significant advantages over manually generated solutions found by experts at NCI.

Control of proliferation and cancer growth by the Hippo signaling pathway

PubMed Central

Ehmer, Ursula; Sage, Julien

2015-01-01

The control of cell division is essential for normal development and the maintenance of cellular homeostasis. Abnormal cell proliferation is associated with multiple pathological states, including cancer. While the Hippo/YAP signaling pathway was initially thought to control organ size and growth, increasing evidence indicates that this pathway also plays a major role in the control of proliferation independent of organ size control. In particular, accumulating evidence indicates that the Hippo/YAP signaling pathway functionally interacts with multiple other cellular pathways and serves as a central node in the regulation of cell division, especially in cancer cells. Here recent observations are highlighted that connect Hippo/YAP signaling to transcription, the basic cell cycle machinery, and the control of cell division. Furthermore, the oncogenic and tumor suppressive attributes of YAP/TAZ are reviewed which emphasizes the relevance of the Hippo pathway in cancer. PMID:26432795

The FORE-SCE model: a practical approach for projecting land cover change using scenario-based modeling

USGS Publications Warehouse

Sohl, Terry L.; Sayler, Kristi L.; Drummond, Mark A.; Loveland, Thomas R.

2007-01-01

A wide variety of ecological applications require spatially explicit, historic, current, and projected land use and land cover data. The U.S. Land Cover Trends project is analyzing contemporary (1973–2000) land-cover change in the conterminous United States. The newly developed FORE-SCE model used Land Cover Trends data and theoretical, statistical, and deterministic modeling techniques to project future land cover change through 2020 for multiple plausible scenarios. Projected proportions of future land use were initially developed, and then sited on the lands with the highest potential for supporting that land use and land cover using a statistically based stochastic allocation procedure. Three scenarios of 2020 land cover were mapped for the western Great Plains in the US. The model provided realistic, high-resolution, scenario-based land-cover products suitable for multiple applications, including studies of climate and weather variability, carbon dynamics, and regional hydrology.

Providing end-to-end QoS for multimedia applications in 3G wireless networks

NASA Astrophysics Data System (ADS)

Guo, Katherine; Rangarajan, Samapth; Siddiqui, M. A.; Paul, Sanjoy

2003-11-01

As the usage of wireless packet data services increases, wireless carriers today are faced with the challenge of offering multimedia applications with QoS requirements within current 3G data networks. End-to-end QoS requires support at the application, network, link and medium access control (MAC) layers. We discuss existing CDMA2000 network architecture and show its shortcomings that prevent supporting multiple classes of traffic at the Radio Access Network (RAN). We then propose changes in RAN within the standards framework that enable support for multiple traffic classes. In addition, we discuss how Session Initiation Protocol (SIP) can be augmented with QoS signaling for supporting end-to-end QoS. We also review state of the art scheduling algorithms at the base station and provide possible extensions to these algorithms to support different classes of traffic as well as different classes of users.

Selective transformations between nanoparticle superlattices via the reprogramming of DNA-mediated interactions

DOE PAGES

Zhang, Yugang; Pal, Suchetan; Srinivasan, Babji; ...

2015-05-25

The rapid development of self-assembly approaches has enabled the creation of materials with desired organization of nanoscale components. However, achieving dynamic control, wherein the system can be transformed on demand into multiple entirely different states, is typically absent in atomic and molecular systems and has remained elusive in designed nanoparticle systems. Here, we demonstrate with in situ small-angle x-ray scattering that, by using DNA strands as inputs, the structure of a three-dimensional lattice of DNA-coated nanoparticles can be switched from an initial 'mother' phase into one of multiple 'daughter' phases. The introduction of different types of re-programming DNA strands modifiesmore » the DNA shells of the nanoparticles within the superlattice, thereby shifting interparticle interactions to drive the transformation into a particular daughter phase. We mapped quantitatively with free-energy calculations the selective re-programming of interactions onto the observed daughter phases.« less

An improved numerical method to compute neutron/gamma deexcitation cascades starting from a high spin state

DOE PAGES

Regnier, D.; Litaize, O.; Serot, O.

2015-12-23

Numerous nuclear processes involve the deexcitation of a compound nucleus through the emission of several neutrons, gamma-rays and/or conversion electrons. The characteristics of such a deexcitation are commonly derived from a total statistical framework often called “Hauser–Feshbach” method. In this work, we highlight a numerical limitation of this kind of method in the case of the deexcitation of a high spin initial state. To circumvent this issue, an improved technique called the Fluctuating Structure Properties (FSP) method is presented. Two FSP algorithms are derived and benchmarked on the calculation of the total radiative width for a thermal neutron capture onmore » 238U. We compare the standard method with these FSP algorithms for the prediction of particle multiplicities in the deexcitation of a high spin level of 143Ba. The gamma multiplicity turns out to be very sensitive to the numerical method. The bias between the two techniques can reach 1.5 γγ/cascade. Lastly, the uncertainty of these calculations coming from the lack of knowledge on nuclear structure is estimated via the FSP method.« less

Multiple Dirac cones and topological magnetism in honeycomb-monolayer transition metal trichalcogenides

NASA Astrophysics Data System (ADS)

Sugita, Yusuke; Miyake, Takashi; Motome, Yukitoshi

2018-01-01

The discovery of monolayer graphene has initiated two fertile fields in condensed matter physics: Dirac semimetals and atomically thin layered materials. When these trends meet again in transition metal compounds, which possess spin and orbital degrees of freedom and strong electron correlations, more exotic phenomena are expected to emerge in the cross section of topological states of matter and Mott physics. Here, we show by using ab initio calculations that a monolayer form of transition metal trichalcogenides (TMTs), which has a honeycomb network of 4 d and 5 d transition metal cations, may exhibit multiple Dirac cones in the electronic structure of the half-filled eg orbitals. The Dirac cones are gapped by the spin-orbit coupling under the trigonal lattice distortion and, hence, can be tuned by tensile strain. Furthermore, we show that electron correlations and carrier doping turn the multiple Dirac semimetal into a topological ferromagnet with high Chern number. Our findings indicate that the honeycomb-monolayer TMTs provide a good playground for correlated Dirac electrons and topologically nontrivial magnetism.

Nonlinear Dynamic Models in Advanced Life Support

NASA Technical Reports Server (NTRS)

Jones, Harry

2002-01-01

To facilitate analysis, ALS systems are often assumed to be linear and time invariant, but they usually have important nonlinear and dynamic aspects. Nonlinear dynamic behavior can be caused by time varying inputs, changes in system parameters, nonlinear system functions, closed loop feedback delays, and limits on buffer storage or processing rates. Dynamic models are usually cataloged according to the number of state variables. The simplest dynamic models are linear, using only integration, multiplication, addition, and subtraction of the state variables. A general linear model with only two state variables can produce all the possible dynamic behavior of linear systems with many state variables, including stability, oscillation, or exponential growth and decay. Linear systems can be described using mathematical analysis. Nonlinear dynamics can be fully explored only by computer simulations of models. Unexpected behavior is produced by simple models having only two or three state variables with simple mathematical relations between them. Closed loop feedback delays are a major source of system instability. Exceeding limits on buffer storage or processing rates forces systems to change operating mode. Different equilibrium points may be reached from different initial conditions. Instead of one stable equilibrium point, the system may have several equilibrium points, oscillate at different frequencies, or even behave chaotically, depending on the system inputs and initial conditions. The frequency spectrum of an output oscillation may contain harmonics and the sums and differences of input frequencies, but it may also contain a stable limit cycle oscillation not related to input frequencies. We must investigate the nonlinear dynamic aspects of advanced life support systems to understand and counter undesirable behavior.

A Markov Environment-dependent Hurricane Intensity Model and Its Comparison with Multiple Dynamic Models

NASA Astrophysics Data System (ADS)

Jing, R.; Lin, N.; Emanuel, K.; Vecchi, G. A.; Knutson, T. R.

2017-12-01

A Markov environment-dependent hurricane intensity model (MeHiM) is developed to simulate the climatology of hurricane intensity given the surrounding large-scale environment. The model considers three unobserved discrete states representing respectively storm's slow, moderate, and rapid intensification (and deintensification). Each state is associated with a probability distribution of intensity change. The storm's movement from one state to another, regarded as a Markov chain, is described by a transition probability matrix. The initial state is estimated with a Bayesian approach. All three model components (initial intensity, state transition, and intensity change) are dependent on environmental variables including potential intensity, vertical wind shear, midlevel relative humidity, and ocean mixing characteristics. This dependent Markov model of hurricane intensity shows a significant improvement over previous statistical models (e.g., linear, nonlinear, and finite mixture models) in estimating the distributions of 6-h and 24-h intensity change, lifetime maximum intensity, and landfall intensity, etc. Here we compare MeHiM with various dynamical models, including a global climate model [High-Resolution Forecast-Oriented Low Ocean Resolution model (HiFLOR)], a regional hurricane model (Geophysical Fluid Dynamics Laboratory (GFDL) hurricane model), and a simplified hurricane dynamic model [Coupled Hurricane Intensity Prediction System (CHIPS)] and its newly developed fast simulator. The MeHiM developed based on the reanalysis data is applied to estimate the intensity of simulated storms to compare with the dynamical-model predictions under the current climate. The dependences of hurricanes on the environment under current and future projected climates in the various models will also be compared statistically.

Building a potential wetland restoration indicator for the contiguous United States

PubMed Central

Horvath, Elena K.; Christensen, Jay R.; Mehaffey, Megan H.; Neale, Anne C.

2018-01-01

Wetlands provide key functions in the landscape from improving water quality, to regulating flows, to providing wildlife habitat. Over half of the wetlands in the contiguous United States (CONUS) have been converted to agricultural and urban land uses. However, over the last several decades, research has shown the benefits of wetlands to hydrologic, chemical, biological processes, spurring the creation of government programs and private initiatives to restore wetlands. Initiatives tend to focus on individual wetland creation, yet the greatest benefits are achieved when strategic restoration planning occurs across a watershed or multiple watersheds. For watershed-level wetland restoration planning to occur, informative data layers on potential wetland areas are needed. We created an indicator of potential wetland areas (PWA), using nationally available datasets to identify characteristics that could support wetland ecosystems, including: poorly drained soils and low-relief landscape positions as indicated by a derived topographic data layer. We compared our PWA with the National Wetlands Inventory (NWI) from 11 states throughout the CONUS to evaluate their alignment. The state-level percentage of NWI-designated wetlands directly overlapping the PWA ranged from 39 to 95%. When we included NWI that was immediately adjacent to the overlapping NWI, our range of correspondence to NWI ranged from 60 to 99%. Wetland restoration is more likely on certain landscapes (e.g., agriculture) than others due to the lack of substantive infrastructure and the potential for the restoration of hydrology; therefore, we combined the National Land Cover Dataset (NLCD) with the PWA to identify potentially restorable wetlands on agricultural land (PRW-Ag). The PRW-Ag identified a total of over 46 million ha with the potential to support wetlands. The largest concentrations of PRW-Ag occurred in the glaciated corn belt of the upper Mississippi River from Ohio to the Dakotas and in the Mississippi Alluvial Valley. The PRW-Ag layer could assist land managers in identifying sites that may qualify for enrollment in conservation programs, where planners can coordinate restoration efforts, or where decision makers can target resources to optimize the services provided across a watershed or multiple watersheds. PMID:29706804

Building a potential wetland restoration indicator for the contiguous United States.

PubMed

Horvath, Elena K; Christensen, Jay R; Mehaffey, Megan H; Neale, Anne C

2017-01-01

Wetlands provide key functions in the landscape from improving water quality, to regulating flows, to providing wildlife habitat. Over half of the wetlands in the contiguous United States (CONUS) have been converted to agricultural and urban land uses. However, over the last several decades, research has shown the benefits of wetlands to hydrologic, chemical, biological processes, spurring the creation of government programs and private initiatives to restore wetlands. Initiatives tend to focus on individual wetland creation, yet the greatest benefits are achieved when strategic restoration planning occurs across a watershed or multiple watersheds. For watershed-level wetland restoration planning to occur, informative data layers on potential wetland areas are needed. We created an indicator of potential wetland areas (PWA), using nationally available datasets to identify characteristics that could support wetland ecosystems, including: poorly drained soils and low-relief landscape positions as indicated by a derived topographic data layer. We compared our PWA with the National Wetlands Inventory (NWI) from 11 states throughout the CONUS to evaluate their alignment. The state-level percentage of NWI-designated wetlands directly overlapping the PWA ranged from 39 to 95%. When we included NWI that was immediately adjacent to the overlapping NWI, our range of correspondence to NWI ranged from 60 to 99%. Wetland restoration is more likely on certain landscapes (e.g., agriculture) than others due to the lack of substantive infrastructure and the potential for the restoration of hydrology; therefore, we combined the National Land Cover Dataset (NLCD) with the PWA to identify potentially restorable wetlands on agricultural land (PRW-Ag). The PRW-Ag identified a total of over 46 million ha with the potential to support wetlands. The largest concentrations of PRW-Ag occurred in the glaciated corn belt of the upper Mississippi River from Ohio to the Dakotas and in the Mississippi Alluvial Valley. The PRW-Ag layer could assist land managers in identifying sites that may qualify for enrollment in conservation programs, where planners can coordinate restoration efforts, or where decision makers can target resources to optimize the services provided across a watershed or multiple watersheds.

Single- and Multiple-dose Pharmacokinetics of a Lorcaserin Extended-release Tablet.

PubMed

Christopher, Ronald; Morgan, Mike; Ferry, Jim; Rege, Bhaskar; Tang, Yong; Kristensen, Allan; Shanahan, William

2016-10-01

Lorcaserin is a serotonin 2C receptor agonist indicated for chronic weight management as an adjunct to diet and exercise. The initial approved formulation is a 10-mg, immediate-release (IR) tablet for administration BID. These studies investigated the single- and multiple-dose pharmacokinetic properties of a new, recently US Food and Drug Administration-approved, extended-release, 20-mg once-daily formulation. We performed 2 separate 2-period, 2-sequence crossover studies in 36 healthy adults: a study comparing the IR formulation to the extended-release formulation under fasting conditions and a study comparing the extended-release formulation under fed and fasted conditions. Compared with lorcaserin IR, the T max after a single dose of lorcaserin extended-release was greater (median, 12 vs 3 hours), and the C max was 26% lower (38.8 vs 52.3 ng/mL). AUC data were bioequivalent for the 2 formulations in both single- and multiple-dose regimens, confirming no formulation effect on lorcaserin bioavailability. In fasted and fed conditions, T max after a single dose was identical (median, 12 hours), but C max was approximately 45% higher in the fed state (mean, 38.5 ng/mL fasted vs 56.1 ng/mL fed). However, at steady state, C max and AUC were determined to be bioequivalent between the fasted and fed states, indicating no clinically relevant food effect on the pharmacokinetic properties of lorcaserin extended-release. The safety profile was consistent between the 2 formulations. Overall, the results indicate that lorcaserin extended-release is a suitable once-daily alternative to the approved IR BID formulation. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

A reconfigurable waveguide for energy-efficient transmission and local manipulation of information in a nanomagnetic device

NASA Astrophysics Data System (ADS)

Adeyeye, Adekunle

In the last few years, interest in propagating-spin-wave based devices has grown largely due to advances in nanotechnology which allows shapes of geometrically confined magnonic elements to be fabricated, the development of new advanced experimental techniques for studying high-frequency magnetization dynamics and the potential use of spin waves as information carriers in spintronic applications. The first part of this talk will focus on design and fabrication strategies for synthesizing nanomagnetic networks with deterministic magnetic ground states. Reliable reconfiguration between ferromagnetic (FM), antiferromagnetic (AFM) and ferrimagnetic ground magnetic states will be shown in rhomboid nanomagnets which stabilize to unique ground states upon field initialized along their short axis. In the second part, a new waveguide consisting of dipolar coupled rhombic shaped nanomagnetic chain that eliminate the requirement of a stand-by power during operation will be presented. The sizes of the nanomagnets are small enough to retain their correct magnetic states once initialized. It will be shown that our waveguide could be used to send spin wave signal around a corner without any stand-by power. Another important parameter for device operation is the manipulation of the output signal, which is similar to a gating operation in a transistor. In our design, gating operation is demonstrated by switching the magnetization of single/multiple nanomagnets in the waveguides in order to manipulate the spin wave amplitude at the output. This work is supported by the National Research Foundation, Prime Minister's Office, under CRP 10-2012-03.

Free energy landscapes for initiation and branching of protein aggregation.

PubMed

Zheng, Weihua; Schafer, Nicholas P; Wolynes, Peter G

2013-12-17

Experiments on artificial multidomain protein constructs have probed the early stages of aggregation processes, but structural details of the species that initiate aggregation remain elusive. Using the associative-memory, water-mediated, structure and energy model known as AWSEM, a transferable coarse-grained protein model, we performed simulations of fused constructs composed of up to four copies of the Titin I27 domain or its mutant I27* (I59E). Free energy calculations enable us to quantify the conditions under which such multidomain constructs will spontaneously misfold. Consistent with experimental results, the dimer of I27 is found to be the smallest spontaneously misfolding construct. Our results show how structurally distinct misfolded states can be stabilized under different thermodynamic conditions, and this result provides a plausible link between the single-molecule misfolding experiments under native conditions and aggregation experiments under denaturing conditions. The conditions for spontaneous misfolding are determined by the interplay among temperature, effective local protein concentration, and the strength of the interdomain interactions. Above the folding temperature, fusing additional domains to the monomer destabilizes the native state, and the entropically stabilized amyloid-like state is favored. Because it is primarily energetically stabilized, the domain-swapped state is more likely to be important under native conditions. Both protofibril-like and branching structures are found in annealing simulations starting from extended structures, and these structures suggest a possible connection between the existence of multiple amyloidogenic segments in each domain and the formation of branched, amorphous aggregates as opposed to linear fibrillar structures.

Clustering of neural code words revealed by a first-order phase transition

NASA Astrophysics Data System (ADS)

Huang, Haiping; Toyoizumi, Taro

2016-06-01

A network of neurons in the central nervous system collectively represents information by its spiking activity states. Typically observed states, i.e., code words, occupy only a limited portion of the state space due to constraints imposed by network interactions. Geometrical organization of code words in the state space, critical for neural information processing, is poorly understood due to its high dimensionality. Here, we explore the organization of neural code words using retinal data by computing the entropy of code words as a function of Hamming distance from a particular reference codeword. Specifically, we report that the retinal code words in the state space are divided into multiple distinct clusters separated by entropy-gaps, and that this structure is shared with well-known associative memory networks in a recallable phase. Our analysis also elucidates a special nature of the all-silent state. The all-silent state is surrounded by the densest cluster of code words and located within a reachable distance from most code words. This code-word space structure quantitatively predicts typical deviation of a state-trajectory from its initial state. Altogether, our findings reveal a non-trivial heterogeneous structure of the code-word space that shapes information representation in a biological network.

Exploring Photoinduced Excited State Evolution in Heterobimetallic Ru(II)-Co(III) Complexes.

PubMed

Kuhar, Korina; Fredin, Lisa A; Persson, Petter

2015-06-18

Quantum chemical calculations provide detailed theoretical information concerning key aspects of photoinduced electron and excitation transfer processes in supramolecular donor-acceptor systems, which are particularly relevant to fundamental charge separation in emerging molecular approaches for solar energy conversion. Here we use density functional theory (DFT) calculations to explore the excited state landscape of heterobimetallic Ru-Co systems with varying degrees of interaction between the two metal centers, unbound, weakly bound, and tightly bound systems. The interplay between structural and electronic factors involved in various excited state relaxation processes is examined through full optimizations of multiple charge/spin states of each of the investigated systems. Low-energy relaxed heterobimetallic states of energy transfer and excitation transfer character are characterized in terms of energy, structure, and electronic properties. These findings support the notion of efficient photoinduced charge separation from a Ru(II)-Co(III) ground state, via initial optical excitation of the Ru-center, to low-energy Ru(III)-Co(II) states. The strongly coupled system has significant involvement of the conjugated bridge, qualitatively distinguishing it from the other two weakly coupled systems. Finally, by constructing potential energy surfaces for the three systems where all charge/spin state combinations are projected onto relevant reaction coordinates, excited state decay pathways are explored.

Prenatal cigarette smoke exposure and early initiation of multiple substance use.

PubMed

Goldschmidt, Lidush; Cornelius, Marie D; Day, Nancy L

2012-06-01

Earlier studies have shown a relation between prenatal cigarette smoke exposure (PCSE) and offspring initiation of tobacco use. No prior study has examined the association between PCSE and early initiation of multiple substances (EIMS) including marijuana and alcohol in addition to tobacco. We investigated the association between PCSE and multiple substance use during adolescence. Pregnant women attending an urban prenatal clinic were selected to participate in the prospective longitudinal study based on their substance use. This study is based on the 16-year follow-up phase and consists of 579 mother-offspring dyads. The women were of lower socioeconomic status, 54% were Black, and 53% reported smoking cigarettes. 52% of the offspring were female. EIMS is a measure of the number of substances initiated prior to age 16 by the adolescents; it ranged from 0 (no initiation, N = 166) to 3 (all, N = 162). Adolescents exposed to tobacco during first trimester of gestation were 1.4 times more likely to initiate multiple substances by age 16 than the nonexposed group. PCSE was a significant predictor of EIMS after controlling for other prenatal exposures, home environment, and demographic characteristics, using ordinal polytomous logistic regression. Other risk factors of EIMS were maternal and adolescent depression, less strict and less involved parenting, offspring attention problems, and lack of participation in a youth club. There is a significant relation between PCSE and adolescent's EIMS.

Initial Implementation Indicators From a Statewide Rollout of SafeCare Within a Child Welfare System

PubMed Central

Whitaker, Daniel J.; Ryan, Kerry A.; Wild, Robert C.; Self-Brown, Shannon; Lutzker, John R.; Shanley, Jenelle R.; Edwards, Anna M.; McFry, Erin A.; Moseley, Colby N.; Hodges, Amanda E.

2013-01-01

There is a strong movement toward implementation of evidence-based practices (EBP) in child welfare systems. The SafeCare parenting model is one of few parent-training models that addresses child neglect, the most common form of maltreatment. Here, the authors describe initial findings from a statewide effort to implement the EBP, SafeCare®, into a state child welfare system. A total of 50 agencies participated in training, with 295 individuals entering training to implement SafeCare. Analyses were conducted to describe the trainee sample, describe initial training and implementation indicators, and to examine correlates of initial training performance and implementation indicators. The quality of SafeCare uptake during training and implementation was high with trainees performing very well on training quizzes and role-plays, and demonstrating high fidelity when implementing SafeCare in the field (performing over 90% of expected behaviors). However, the quantity of implementation was generally low, with relatively few providers (only about 25%) implementing the model following workshop training. There were no significant predictors of training or implementation performance, once corrections for multiple comparisons were applied. The Discussion focuses on challenges to large-scale system-wide implementation of EBP. PMID:22146860

Annular wave packets at Dirac points in graphene and their probability-density oscillation.

PubMed

Luo, Ji; Valencia, Daniel; Lu, Junqiang

2011-12-14

Wave packets in graphene whose central wave vector is at Dirac points are investigated by numerical calculations. Starting from an initial Gaussian function, these wave packets form into annular peaks that propagate to all directions like ripple-rings on water surface. At the beginning, electronic probability alternates between the central peak and the ripple-rings and transient oscillation occurs at the center. As time increases, the ripple-rings propagate at the fixed Fermi speed, and their widths remain unchanged. The axial symmetry of the energy dispersion leads to the circular symmetry of the wave packets. The fixed speed and widths, however, are attributed to the linearity of the energy dispersion. Interference between states that, respectively, belong to two branches of the energy dispersion leads to multiple ripple-rings and the probability-density oscillation. In a magnetic field, annular wave packets become confined and no longer propagate to infinity. If the initial Gaussian width differs greatly from the magnetic length, expanding and shrinking ripple-rings form and disappear alternatively in a limited spread, and the wave packet resumes the Gaussian form frequently. The probability thus oscillates persistently between the central peak and the ripple-rings. If the initial Gaussian width is close to the magnetic length, the wave packet retains the Gaussian form and its height and width oscillate with a period determined by the first Landau energy. The wave-packet evolution is determined jointly by the initial state and the magnetic field, through the electronic structure of graphene in a magnetic field. © 2011 American Institute of Physics

Modeling Smoke Plume-Rise and Dispersion from Southern United States Prescribed Burns with Daysmoke.

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

Achtemeier, Gary, L.; Goodrick, Scott, A.; Liu, Yongqiang

2011-08-19

We present Daysmoke, an empirical-statistical plume rise and dispersion model for simulating smoke from prescribed burns. Prescribed fires are characterized by complex plume structure including multiple-core updrafts which makes modeling with simple plume models difficult. Daysmoke accounts for plume structure in a three-dimensional veering/sheering atmospheric environment, multiple-core updrafts, and detrainment of particulate matter. The number of empirical coefficients appearing in the model theory is reduced through a sensitivity analysis with the Fourier Amplitude Sensitivity Test (FAST). Daysmoke simulations for 'bent-over' plumes compare closely with Briggs theory although the two-thirds law is not explicit in Daysmoke. However, the solutions for themore » 'highly-tilted' plume characterized by weak buoyancy, low initial vertical velocity, and large initial plume diameter depart considerably from Briggs theory. Results from a study of weak plumes from prescribed burns at Fort Benning GA showed simulated ground-level PM2.5 comparing favorably with observations taken within the first eight kilometers of eleven prescribed burns. Daysmoke placed plume tops near the lower end of the range of observed plume tops for six prescribed burns. Daysmoke provides the levels and amounts of smoke injected into regional scale air quality models. Results from CMAQ with and without an adaptive grid are presented.« less

Condensation and transport in the totally asymmetric inclusion process (TASIP)

NASA Astrophysics Data System (ADS)

Knebel, Johannes; Weber, Markus F.; Krueger, Torben; Frey, Erwin

Transport phenomena are often modeled by the hopping of particles on regular lattices or networks. Such models describe, e.g., the exclusive movement of molecular motors along microtubules: no two motors may occupy the same site. In our work, we study inclusion processes that are the bosonic analogues of the fermionic exclusion processes. In inclusion processes, many particles may occupy a single site and hopping rates depend linearly on the occupation of departure and arrival sites. Particles thus attract other particles to their own site. Condensation occurs when particles collectively cluster in one or multiple sites, whereas other sites become depleted.We showed that inclusion processes describe both the selection of strategies in evolutionary zero-sum games and the condensation of non-interacting bosons into multiple quantum states in driven-dissipative systems. The condensation is captured by the antisymmetric Lotka-Volterra equation (ALVE), which constitutes a nonlinearly coupled dynamical system. We derived an algebraic method to analyze the ALVE and to determine the condensates. Our approach allows for the design of networks that result in condensates with oscillating occupations, and yields insight into the interplay between network topology and transport properties. Deutsche Forschungsgemeinschaft (SFB-TR12), German Excellence Initiative (Nanosystems Initiative Munich), Center for NanoScience Munich.

Productive engagement among older Americans: prevalence, patterns, and implications for public policy.

PubMed

Hinterlong, James E

2008-01-01

This study estimates the prevalence of productive engagement among adults aged 60 and over residing in the United States over a nine-year period. We analyze three waves of data from the Americans' Changing Lives Study, which allows the findings to describe the non-institutionalized older American population. Focusing upon five activities--formal paid employment, irregular paid work, unpaid volunteerism, caregiving, and informal assistance to others--we identify changes in the engagement rates, examine the extent to which engagement occurs through single or multiple concurrent activities, and document intra-individual patterns of engagement within and across forms of productive activity, including the continuity, initiation, and cessation of involvement. The findings reveal that late-life productive engagement is widespread, with the majority of older individuals involved in multiple forms of activity concurrently. Non-market-based activities such as caregiving, informal assistance, and volunteering are most prevalent. Initiation and cessation of activities are common and yield more complex patterns and lower rates of non-participation than are revealed in cross-sectional analyses. Time spent in productive engagement is highly variable and exhibits an overall decline across time. We conclude by highlighting policy strategies to increase the availability and quality of opportunities for productive engagement and promote planning for engagement in late life.

Development of, and initial validity evidence for, the referee self-efficacy scale: a multistudy report.

PubMed

Myers, Nicholas D; Feltz, Deborah L; Guillén, Félix; Dithurbide, Lori

2012-12-01

The purpose of this multistudy report was to develop, and then to provide initial validity evidence for measures derived from, the Referee Self-Efficacy Scale. Data were collected from referees (N = 1609) in the United States (n = 978) and Spain (n = 631). In Study 1 (n = 512), a single-group exploratory structural equation model provided evidence for four factors: game knowledge, decision making, pressure, and communication. In Study 2 (n = 1153), multiple-group confirmatory factor analytic models provided evidence for partial factorial invariance by country, level of competition, team gender, and sport refereed. In Study 3 (n = 456), potential sources of referee self-efficacy information combined to account for a moderate or large amount of variance in each dimension of referee self-efficacy with years of referee experience, highest level refereed, physical/mental preparation, and environmental comfort, each exerting at least two statistically significant direct effects.

Atomistic study on shock behaviour of NiTi shape memory alloy

NASA Astrophysics Data System (ADS)

Yin, Qiuyun; Wu, Xianqian; Huang, Chenguang

2017-06-01

The shock behaviour of NiTi shape memory alloy is investigated by using molecular dynamics simulation. The nano-pillar samples of the alloy are subjected to the impact of a piston with a velocity of 350 m/s at initial environment temperatures of 325 and 500 K. At 325 K, we observe two different pathways of the formation of BCO phase, the gradient twins, and the detwinning phenomena, strongly depending on the local stress and the deformation state. As the initial temperature increases to 500 K, the plasticity is dominated by the dislocation movements rather than the twinning at 325 K. The phase transformation and plasticity result in stress attenuation when the stress wave propagates through the nano-pillar. Furthermore, it is interesting to note that multiple stress peaks occur due to the formation of local complex atomic structures with various wave speeds, leading to the catch up and overlap of the stress waves.

MS lesion segmentation using a multi-channel patch-based approach with spatial consistency

NASA Astrophysics Data System (ADS)

Mechrez, Roey; Goldberger, Jacob; Greenspan, Hayit

2015-03-01

This paper presents an automatic method for segmentation of Multiple Sclerosis (MS) in Magnetic Resonance Images (MRI) of the brain. The approach is based on similarities between multi-channel patches (T1, T2 and FLAIR). An MS lesion patch database is built using training images for which the label maps are known. For each patch in the testing image, k similar patches are retrieved from the database. The matching labels for these k patches are then combined to produce an initial segmentation map for the test case. Finally a novel iterative patch-based label refinement process based on the initial segmentation map is performed to ensure spatial consistency of the detected lesions. A leave-one-out evaluation is done for each testing image in the MS lesion segmentation challenge of MICCAI 2008. Results are shown to compete with the state-of-the-art methods on the MICCAI 2008 challenge.

Temperature Controller System for Gas Gun Targets

NASA Astrophysics Data System (ADS)

Bucholtz, S. M.; Gehr, R. J.; Rupp, T. D.; Sheffield, S. A.; Robbins, D. L.

2006-07-01

A temperature controller system capable of heating and cooling gas gun targets over the range -75°C to +120°C was designed and tested. The system uses cold nitrogen gas from a liquid nitrogen Dewar for cooling and compressed air for heating. Two gas flow heaters control the gas temperature for both heating and cooling. One heater controls the temperature of the target mounting plate and the other the temperature of a copper tubing coil surrounding the target. Each heater is separately adjustable, so the target material will achieve a uniform temperature throughout its volume. A magnetic gauge membrane with integrated thermocouples was developed to measure the internal temperature of the target. Using this system, multiple magnetic gauge shock experiments, including equation-of-state measurements and shock initiation of high explosives, can be performed over a range of initial temperatures. Successful heating and cooling tests were completed on Teflon samples.

Influence of microstructure on the fretting resistance of Al-Cu-Li alloys

NASA Astrophysics Data System (ADS)

Delacroix, Jessica; Cazottes, Sophie; Daniélou, Armelle; Fouvry, Siegfried; Buffiere, Jean-Yves

The resistance of two Al-Cu-Li alloys (2050 and 2196) to fretting has been investigated. For each material two heat treatments have been studied (T8 and low temperature ageing). Fretting tests with a cylinder-plane configuration have been performed in the partial slip regime. The results obtained show that the low temperature temper gives a better resistance to fretting crack initiation and propagation than the T8 temper for both alloys. The 3D shape of the fretting cracks has been observed by high resolution synchrotron X-ray tomography. Multiple initiation sites were observed below the contact. In their early stages of development, the fretting cracks grow approximately radially within the material leading to thumb nail cracks which eventually merge laterally. The difference in fretting resistance is analysed with respect to the 3D fracture surface of the fretting cracks in relation with the alloys precipitation state.

[Trends and inequalities in risk behaviors among adolescents: a comparison of birth cohorts in Pelotas, Rio Grande do Sul State, Brazil].

PubMed

Arroyave, Leidy Johanna Ocampo; Restrepo-Méndez, María Clara; Horta, Bernardo Lessa; Menezes, Ana Maria Baptista; Gigante, Denise Petrucci; Gonçalves, Helen

2016-10-10

This study focuses on trends and inequalities in health risk behaviors among adolescents. A cross-sectional study compared two birth cohorts in the city of Pelotas, Rio Grande do Sul State, Brazil. The sample included 1,281 adolescents from the 1982 cohort and 4,106 from the 1993 cohort, followed in 2001 and 2011, respectively. The study recorded alcohol intake, illegal drug use, smoking, sexual initiation < 16 years, lack of condom use, and multiple sex partners. Total prevalence rates were calculated for each cohort, stratified by gender and per capita income, besides absolute and relative measures of inequality. There was a decrease from 2001 to 2011 in prevalence rates for trying alcohol, illegal drug use, smoking, and lack of condom use, and an increase in the number of sex partners. The gap between boys and girls increased for non-use of condoms and decreased for the other behaviors. The gap between income groups decreased for sexual initiation before 16 years of age and increased for episodes of intoxication. Socioeconomic inequalities persist, despite the downward trend in prevalence of risk behaviors.

The effect of hospital-physician integration on health information technology adoption.

PubMed

Lammers, Eric

2013-10-01

The US federal government has recently made a substantial investment to enhance the US health information technology (IT) infrastructure. Previous literature on the impact of IT on firm performance across multiple industries has emphasized the importance of a process of co-invention whereby organizations develop complementary practices to achieve greater benefit from their IT investments. In health care, employment of physicians by hospitals can confer greater administrative control to hospitals over physicians' actions and resources and thus enable the implementation of new technology and initiatives aimed at maximizing benefit from use of the technology. In this study, I tested for the relationship between hospital employment of physicians and hospitals' propensity to use health IT. I used state laws that prohibit hospital employment of physicians as an instrument to account for the endogenous relationship with hospital IT use. Hospital employment of physicians is associated with significant increases in the probability of hospital health IT use. Therefore, subsidization of health IT among hospitals not employing physicians may be less efficient. Furthermore, state laws prohibiting hospitals from employing physicians may inhibit adoption of health IT, thus working against policy initiatives aimed at promoting use of the technology. Copyright © 2012 John Wiley & Sons, Ltd.

Wyoming Landscape Conservation Initiative data management and integration

USGS Publications Warehouse

Latysh, Natalie; Bristol, R. Sky

2011-01-01

Six Federal agencies, two State agencies, and two local entities formally support the Wyoming Landscape Conservation Initiative (WLCI) and work together on a landscape scale to manage fragile habitats and wildlife resources amidst growing energy development in southwest Wyoming. The U.S. Geological Survey (USGS) was tasked with implementing targeted research and providing scientific information about southwest Wyoming to inform the development of WLCI habitat enhancement and restoration projects conducted by land management agencies. Many WLCI researchers and decisionmakers representing the Bureau of Land Management, U.S. Fish and Wildlife Service, the State of Wyoming, and others have overwhelmingly expressed the need for a stable, robust infrastructure to promote sharing of data resources produced by multiple entities, including metadata adequately describing the datasets. Descriptive metadata facilitates use of the datasets by users unfamiliar with the data. Agency representatives advocate development of common data handling and distribution practices among WLCI partners to enhance availability of comprehensive and diverse data resources for use in scientific analyses and resource management. The USGS Core Science Informatics (CSI) team is developing and promoting data integration tools and techniques across USGS and partner entity endeavors, including a data management infrastructure to aid WLCI researchers and decisionmakers.

Use of Data Libraries for IAEA Nuclear Security Assessment Methodologies (NUSAM) [section 5.4

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

Shull, D.; Lane, M.

2015-06-23

Data libraries are essential for the characterization of the facility and provide the documented input which enables the facility assessment results and subsequent conclusions. Data Libraries are historical, verifiable, quantified, and applicable collections of testing data on different types of barriers, sensors, cameras, procedures, and/or personnel. Data libraries are developed and maintained as part of any assessment program or process. Data is collected during the initial stages of facility characterization to aid in the model and/or simulation development process. Data library values may also be developed through the use of state testing centers and/or site resources by testing different typesmore » of barriers, sensors, cameras, procedures, and/or personnel. If no data exists, subject matter expert opinion and manufacturer's specifications/ testing values can be the basis for initially assigning values, but are generally less reliable and lack appropriate confidence measures. The use of existing data libraries that have been developed by a state testing organization reduces the assessment costs by establishing standard delay, detection and assessment values for use by multiple sites or facilities where common barriers and alarms systems exist.« less

Differential tumor biology effects of double-initiation in a mouse skin chemical carcinogenesis model comparing wild type versus protein kinase Cepsilon overexpression mice.

PubMed

Li, Yafan; Wheeler, Deric L; Ananthaswamy, Honnavara N; Verma, Ajit K; Oberley, Terry D

2007-12-01

Our previous studies showed that protein kinase Cepsilon (PKCepsilon) verexpression in mouse skin resulted in metastatic squamous cell carcinoma (SCC) elicited by single 7,12-dimethylbenz(a)anthracene (DMBA)-initiation and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promotion in the absence of preceding papilloma formation as is typically observed in wild type mice. The present study demonstrates that double-DMBA initiation modulates tumor incidence, multiplicity, and latency period in both wild type and PKCepsilon overexpression transgenic (PKCepsilon-Tg) mice. After 17 weeks (wks) of tumor promotion, a reduction in papilloma multiplicity was observed in double- versus single-DMBA initiated wild type mice. Papilloma multiplicity was inversely correlated with cell death indices of interfollicular keratinocytes, indicating decreased papilloma formation was caused by increased cell death and suggesting the origin of papillomas is in interfollicular epidermis. Double-initiated PKCepsilon-Tg mice had accelerated carcinoma formation and cancer incidence in comparison to single-initiated PKCepsilon-Tg mice. Morphologic analysis of mouse skin following double initiation and tumor promotion showed a similar if not identical series of events to those previously observed following single initiation and tumor promotion: putative preneoplastic cells were observed arising from hyperplastic hair follicles (HFs) with subsequent cancer cell infiltration into the dermis. Single-initiated PKCepsilon-Tg mice exhibited increased mitosis in epidermal cells of HFs during tumor promotion.

High multiplicity α-particle breakup measurements to study α-condensate states

NASA Astrophysics Data System (ADS)

Bishop, J.; Kokalova, Tz; Freer, M.; Assie, M.; Acosta, L.; Bailey, S.; Cardella, G.; Curtis, N.; De Filippo, E.; Dell'Aquila, D.; De Luca, S.; Francalanza, L.; Gnoffo, B.; Lanzalone, G.; Lombardo, I.; Martorana, N.; Norella, S.; Pagano, A.; Pagano, E. V.; Papa, M.; Pirrone, S.; Politi, G.; Rizzo, F.; Russotto, P.; Quattrocchi, L.; Smith, R.; Stefan, I.; Trifirò, A.; Trimarchì, M.; Verde, G.; Vigilante, M.; Wheldon, C.

2017-06-01

An experiment was performed to investigate α-condensate states via high α-particle multiplicity breakup. The nucleus of interest was 28Si therefore to measure multiplicity 7 particle breakup events, a highly granular detector with a high solid angle coverage was required. For this purpose, the CHIMERA and FARCOS detectors at INFN LNS were employed. Particle identification was achieved through ΔE-E energy loss. The α-particle multiplicity was measured at three beam energies to investigate different excitation regimes in 28Si. At a beam energy where the energy is sufficient to provide the 7 α-particles with enough energy to be identified using the ΔE-E method, multiplicity 7 events can be seen. Given these high multiplicity events, the particles can be reconstructed to investigate the breakup of α-condensate states. Analysing the decay paths of these states can elucidate whether the state of interest corresponds to a non-cluster, clustered or condensed state.

Application of models to conservation planning for terrestrial birds in North America

USGS Publications Warehouse

Fitzgerald, Jane A.; Thogmartin, Wayne E.; Dettmers, Randy; Jones, Tim; Rustay, Christopher; Ruth, Janet M.; Thompson, Frank R.; Will, Tom; Millspaugh, Joshua J.; Thompson, Frank R.

2009-01-01

Partners in Flight (PIF), a public–private coalition for the conservation of land birds, has developed one of four international bird conservation plans recognized under the auspices of the North American Bird Conservation Initiative (NABCI). Partners in Flight prioritized species most in need of conservation attention and set range-wide population goals for 448 species of terrestrial birds. Partnerships are now tasked with developing spatially explicit estimates of the distribution, and abundance of priority species across large ecoregions and identifying habitat acreages needed to support populations at prescribed levels. The PIF Five Elements process of conservation design identifies five steps needed to implement all bird conservation at the ecoregional scale. Habitat assessment and landscape characterization describe the current amounts of different habitat types and summarize patch characteristics, and landscape configurations that define the ability of a landscape to sustain healthy bird populations and are a valuable first step to describing the planning area before pursuing more complex species-specific models. Spatially linked database models, landscape-scale habitat suitability models, and statistical models are viable alternatives for predicting habitat suitability or bird abundance across large planning areas to help assess conservation opportunities, design landscapes to meet population objectives, and monitor change in habitat suitability or bird numbers over time.Bird conservation in the United States is a good example of the use of models in large-scale wildlife conservation planning because of its geographic extent, focus on multiple species, involvement of multiple partners, and use of simple to complex models. We provide some background on the recent development of bird conservation initiatives in the United States and the approaches used for regional conservation assessment and planning. We focus on approaches being used for landscape characterization and assessment, and bird population response modeling.

Quality assured measurements of animal building emissions: gas concentrations.

PubMed

Heber, Albert J; Ni, Ji-Qin; Lim, Teng T; Tao, Pei-Chun; Schmidt, Amy M; Koziel, Jacek A; Beasley, David B; Hoff, Steven J; Nicolai, Richard E; Jacobson, Larry D; Zhang, Yuanhui

2006-10-01

Comprehensive field studies were initiated in 2002 to measure emissions of ammonia (NH3), hydrogen sulfide (H2S), carbon dioxide (CO2), methane (CH4), nonmethane hydrocarbons (NMHC), particulate matter <10 microm in diameter, and total suspended particulate from swine and poultry production buildings in the United States. This paper focuses on the quasicontinuous gas concentration measurement at multiple locations among paired barns in seven states. Documented principles, used in air pollution monitoring at industrial sources, were applied in developing quality assurance (QA) project plans for these studies. Air was sampled from multiple locations with each gas analyzed with one high quality commercial gas analyzer that was located in an environmentally controlled on-farm instrument shelter. A nominal 4 L/min gas sampling system was designed and constructed with Teflon wetted surfaces, bypass pumping, and sample line flow and pressure sensors. Three-way solenoids were used to automatically switch between multiple gas sampling lines with > or =10 min sampling intervals. Inside and outside gas sampling probes were between 10 and 115 m away from the analyzers. Analyzers used chemiluminescence, fluorescence, photoacoustic infrared, and photoionization detectors for NH3, H2S, CO2, CH4, and NMHC, respectively. Data were collected using personal computer-based data acquisition hardware and software. This paper discusses the methodology of gas concentration measurements and the unique challenges that livestock barns pose for achieving desired accuracy and precision, data representativeness, comparability and completeness, and instrument calibration and maintenance.

Building International Research Partnerships in the North Atlantic-Arctic Region

NASA Astrophysics Data System (ADS)

Benway, Heather M.; Hofmann, Eileen; St. John, Michael

2014-09-01

The North Atlantic-Arctic region, which is critical to the health and socioeconomic well being of North America and Europe, is susceptible to climate-driven changes in circulation, biogeochemistry, and marine ecosystems. The need for strong investment in the study of biogeochemical and ecosystem processes and interactions with physical processes over a range of time and space scales in this region was clearly stated in the 2013 Galway Declaration, an intergovernmental statement on Atlantic Ocean cooperation (http://europa.eu/rapid/press-release_IP-13-459_en.htm). Subsequently, a workshop was held to bring together researchers from the United States, Canada, and Europe with expertise across multiple disciplines to discuss an international research initiative focused on key features, processes, and ecosystem services (e.g., Atlantic Meridional Overturning Circulation, spring bloom dynamics, fisheries, etc.) and associated sensitivities to climate changes.

Simultaneous Estimation of Microphysical Parameters and Atmospheric State Variables With Radar Data and Ensemble Square-root Kalman Filter

NASA Astrophysics Data System (ADS)

Tong, M.; Xue, M.

2006-12-01

An important source of model error for convective-scale data assimilation and prediction is microphysical parameterization. This study investigates the possibility of estimating up to five fundamental microphysical parameters, which are closely involved in the definition of drop size distribution of microphysical species in a commonly used single-moment ice microphysics scheme, using radar observations and the ensemble Kalman filter method. The five parameters include the intercept parameters for rain, snow and hail/graupel, and the bulk densities of hail/graupel and snow. Parameter sensitivity and identifiability are first examined. The ensemble square-root Kalman filter (EnSRF) is employed for simultaneous state and parameter estimation. OSS experiments are performed for a model-simulated supercell storm, in which the five microphysical parameters are estimated individually or in different combinations starting from different initial guesses. When error exists in only one of the microphysical parameters, the parameter can be successfully estimated without exception. The estimation of multiple parameters is found to be less robust, with end results of estimation being sensitive to the realization of the initial parameter perturbation. This is believed to be because of the reduced parameter identifiability and the existence of non-unique solutions. The results of state estimation are, however, always improved when simultaneous parameter estimation is performed, even when the estimated parameters values are not accurate.

Origin of the satellites Lα3, Lα4 and Lα5 in the elements from 40Zr to 50Sn

NASA Astrophysics Data System (ADS)

Kendurkar, Renuka; Shrivastava, B. D.

2014-09-01

The origin of the Lα satellites Lα3, Lα4 and Lα5 have been explained in the elements from 40Zr to 50Sn, on the basis of multiple ionization theory. The energies and intensities of the various transitions corresponding to the L3Mx - MxM4,5 (where x = 1-5) transition array, which may give rise to these satellites, have been calculated theoretically. The energies of the transitions have been calculated using the available Hartree-Fock-Slater data for the energies of K-LM and L-MM Auger transitions. The intensities of the various transitions have been estimated by considering cross sections for L1-L3Mx Coster-Kronig transitions as well as for M-shell shake-off process occurring simultaneous to a L3 hole creation. The total cross sections for initial two-hole states L3Mx have then been distributed statistically amongst the various allowed transitions from these initial states to the final states MxM4,5. By assuming each transition as a Gaussian line, theoretical satellite spectrum has been computed as the sum of these Gaussian curves. The energies of the satellites, as obtained from the theoretical spectrum, have been found to be comparable with the measured energies of the satellites Lα3, Lα4 and Lα5. Consequently, these satellites have been assigned the transitions.

Initial Correction versus Negative Marking in Multiple Choice Examinations

ERIC Educational Resources Information Center

Van Hecke, Tanja

2015-01-01

Optimal assessment tools should measure in a limited time the knowledge of students in a correct and unbiased way. A method for automating the scoring is multiple choice scoring. This article compares scoring methods from a probabilistic point of view by modelling the probability to pass: the number right scoring, the initial correction (IC) and…

Technology Integration in a One-to-One Laptop Initiative: A Multiple Case Study Analysis

ERIC Educational Resources Information Center

Jones, Marsha B.

2013-01-01

The purpose of this multiple case study analysis was to examine teachers' experiences and perceptions in order to understand what actions and interactions supported or inhibited technology integration during a one-to-one laptop initiative. This research sought to gain teachers' perspectives on the challenges and successes they faced as classroom…

Factors associated with hookah use initiation among adolescents.

PubMed

Reveles, Caroline C; Segri, Neuber J; Botelho, Clovis

2013-01-01

to determine the prevalence and to analyze factors associated with hookah use initiation among adolescents. This was a cross-sectional study, in which questionnaires were collected from 495 students attending public and private schools of the urban area of the city of Várzea Grande, in the state of Mato Grosso, Brazil. Data were analyzed through descriptive, bivariate, and multiple Poisson regression analyses. A total of 19.7% students had tried a hookah. The use of hookah was associated with the final period of adolescence [PR=6.54 (2.79, 15.32)]; enrollment in private schools [PR=2.23 (1.73, 2.88)]; and presence of work activities [PR=1.80 (1.17, 2.78)]. The proportion of adolescents that had tried a hookah was high. The influence of age, work activities, and class period on smoking initiation using the hookah was observed. Preventive measures encompassing all forms of tobacco smoking should be targeted at adolescents in the school environment, aiming at tobacco use control. Copyright © 2013 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Electrically stimulated contractions of Vorticella convallaria

NASA Astrophysics Data System (ADS)

Kantha, Deependra; van Winkle, David

2009-03-01

The contraction of Vorticella convallaria was triggered by applying a voltage pulse in its host culturing medium. The 50V, 1ms wide pulse was applied across platinum wires separated by 0.7 cm on a microscope slide. The contractions were recorded as cines (image sequences) by a Phantom V5 camera (Vision Research) on a bright field microscope with 20X objective, with the image size of 256 pixels x 128 pixels at 7352 pictures per second. The starting time of the cines was synchronized with the starting of the electrical pulse. We recorded five contractions of each of 12 organisms. The cines were analyzed to obtain the initiation time, defined as the difference in time between the leading edge of the electrical pulse and the first frame showing zooid movement. From multiple contractions of same organism, we found the initiation time is reproducible. In comparing different organisms, we found the average initiation time of 1.73 ms with a standard deviation of 0.63 ms. This research is supported by the state of Florida (MARTECH) and Research Corporation.

Linking Federal, State, and Local Adaptation Strategies in New York (Invited)

NASA Astrophysics Data System (ADS)

Rosenzweig, C.

2010-12-01

New York City and New York State are leaders in adaptation in the U.S. In 2008 Mayor Bloomberg convened the NYC Climate Change Adaptation Task Force and the New York City Panel on Climate Change (NPCC). Also in 2008, the New York State Energy Research and Development Authority (NYSERDA) initiated the Integrated Assessment for Effective Climate Change Adaptation Strategies (ClimAID), to provide New York State decision-makers with cutting-edge information on its vulnerability to climate change and to facilitate the development of adaptation strategies informed by both local experience and scientific knowledge. The two efforts are working together to develop effective adaptation strategies across multiple jurisdictions. The New York Task Force consists of approximate 40 city, state, and federal agencies, regional public authorities, and private companies that operate, maintain, or regulate critical infrastructure in the region. The NPCC consisted of climate change and impacts scientists, and legal, insurance, and risk-management experts and served as the technical advisory body for the Mayor and the Task Force on issues related to climate change, impacts, and adaptation. In its 2010 report, the NPCC recommended adoption of a risk-based approach to climate change; creation of a monitoring program to track and analyze key climate change factors, impacts, and adaptation indicators; review of relevant standards and codes; inclusion of multiple layers of government and a wide range of public and private stakeholder experts to build buy-in; and formation of crucial partnerships for development of coordinated adaptation strategies. The task now is for these partnerships to create pilot programs that move adaptation from the planning phase to implementation; urban areas can provide critical ‘test-beds’ for such efforts.

Dissipative production of a maximally entangled steady state of two quantum bits.

PubMed

Lin, Y; Gaebler, J P; Reiter, F; Tan, T R; Bowler, R; Sørensen, A S; Leibfried, D; Wineland, D J

2013-12-19

Entangled states are a key resource in fundamental quantum physics, quantum cryptography and quantum computation. Introduction of controlled unitary processes--quantum gates--to a quantum system has so far been the most widely used method to create entanglement deterministically. These processes require high-fidelity state preparation and minimization of the decoherence that inevitably arises from coupling between the system and the environment, and imperfect control of the system parameters. Here we combine unitary processes with engineered dissipation to deterministically produce and stabilize an approximate Bell state of two trapped-ion quantum bits (qubits), independent of their initial states. Compared with previous studies that involved dissipative entanglement of atomic ensembles or the application of sequences of multiple time-dependent gates to trapped ions, we implement our combined process using trapped-ion qubits in a continuous time-independent fashion (analogous to optical pumping of atomic states). By continuously driving the system towards the steady state, entanglement is stabilized even in the presence of experimental noise and decoherence. Our demonstration of an entangled steady state of two qubits represents a step towards dissipative state engineering, dissipative quantum computation and dissipative phase transitions. Following this approach, engineered coupling to the environment may be applied to a broad range of experimental systems to achieve desired quantum dynamics or steady states. Indeed, concurrently with this work, an entangled steady state of two superconducting qubits was demonstrated using dissipation.

How we manage autologous stem cell transplantation for patients with multiple myeloma

PubMed Central

Dingli, David

2014-01-01

An estimated 22 350 patients had multiple myeloma diagnosed in 2013, representing 1.3% of all new cancers; 10 710 deaths are projected, representing 1.8% of cancer deaths. Approximately 0.7% of US men and women will have a myeloma diagnosis in their lifetime, and with advances in therapy, 77 600 US patients are living with myeloma. The 5-year survival rate was 25.6% in 1989 and was 44.9% in 2005. The median age at diagnosis is 69 years, with 62.4% of patients aged 65 or older at diagnosis. Median age at death is 75 years. The rate of new myeloma cases has been rising 0.7% per year during the past decade. The most common indication for autologous stem cell transplantation in the United States is multiple myeloma, and this article is designed to provide the specifics of organizing a transplant program for multiple myeloma. We review the data justifying use of stem cell transplantation as initial management in myeloma patients. We provide selection criteria that minimize the risks of transplantation. Specific guidelines on mobilization and supportive care through the transplant course, as done at Mayo Clinic, are given. A review of the data on tandem vs sequential autologous transplants is provided. PMID:24973360

Systematic procedure for designing processes with multiple environmental objectives.

PubMed

Kim, Ki-Joo; Smith, Raymond L

2005-04-01

Evaluation of multiple objectives is very important in designing environmentally benign processes. It requires a systematic procedure for solving multiobjective decision-making problems due to the complex nature of the problems, the need for complex assessments, and the complicated analysis of multidimensional results. In this paper, a novel systematic procedure is presented for designing processes with multiple environmental objectives. This procedure has four steps: initialization, screening, evaluation, and visualization. The first two steps are used for systematic problem formulation based on mass and energy estimation and order of magnitude analysis. In the third step, an efficient parallel multiobjective steady-state genetic algorithm is applied to design environmentally benign and economically viable processes and to provide more accurate and uniform Pareto optimal solutions. In the last step a new visualization technique for illustrating multiple objectives and their design parameters on the same diagram is developed. Through these integrated steps the decision-maker can easily determine design alternatives with respect to his or her preferences. Most importantly, this technique is independent of the number of objectives and design parameters. As a case study, acetic acid recovery from aqueous waste mixtures is investigated by minimizing eight potential environmental impacts and maximizing total profit. After applying the systematic procedure, the most preferred design alternatives and their design parameters are easily identified.

Results of a multi-media multiple behavior obesity prevention program for adolescents.

PubMed

Mauriello, Leanne M; Ciavatta, Mary Margaret H; Paiva, Andrea L; Sherman, Karen J; Castle, Patricia H; Johnson, Janet L; Prochaska, Janice M

2010-12-01

This study reports on effectiveness trial outcomes of Health in Motion, a computer tailored multiple behavior intervention for adolescents. Using school as level of assignment, students (n=1800) from eight high schools in four states (RI, TN, MA, and NY) were stratified and randomly assigned to no treatment or a multi-media intervention for physical activity, fruit and vegetable consumption, and limited TV viewing between 2006 and 2007. Intervention effects on continuous outcomes, on movement to action and maintenance stages, and on stability within action and maintenance stages were evaluated using random effects modeling. Effects were most pronounced for fruit and vegetable consumption and for total risks across all time points and for each behavior immediately post intervention. Co-variation of behavior change occurred within the treatment group, where individuals progressing to action or maintenance for one behavior were 1.4-4.2 times more likely to make similar progress on another behavior. Health in Motion is an innovative, multiple behavior obesity prevention intervention relevant for all adolescents that relies solely on interactive technology to deliver tailored feedback. The outcomes of the effectiveness trial demonstrate both an ability to initiate behavior change across multiple energy balance behaviors simultaneously and feasibility for ease of dissemination. Copyright © 2010 The Institute For Cancer Prevention. Published by Elsevier Inc. All rights reserved.

Mass murder in a university setting: analysis of the medical examiner's response.

PubMed

Fierro, Marcella F

2007-09-01

Seung-Hui Cho, a student at Virginia Polytechnic Institute and State University (Virginia Tech), shot and killed 33 students and faculty, including himself, on the morning of April 16, 2007. A retrospective review of the medical examiner system response to this multiple fatality event was undertaken to identify which procedures were and were not effective. Case records, spreadsheets, telephone call logs, notes, and after-action interviews of staff were reviewed and analyzed. Recommendations were developed to improve the management of the multiple components of a high-profile multiple fatality event. One autopsy took place on Monday, April 16, 12 on Tuesday, April 17, and 20 on Wednesday, April 18. Pathologists archived the biopsies of major organs in formalin. Slides were made of entrance wounds that exhibited residues. Blood for alcohols was collected from victims. Blood for alcohols, acid, base, and neutral drugs was collected from Cho for analysis. Standard forensic pathology procedures worked and timely postmortem examinations were completed. The victim identification component of the family assistance center must be established and staffed at the time of the initial response. Public information officers need training in morgue and medicolegal death management and in ways to effectively communicate with different audiences about multiple fatality management procedures.

Ultrafast terahertz snapshots of excitonic Rydberg states and electronic coherence in an organometal halide perovskite

DOE PAGES

Luo, Liang; Men, Long; Liu, Zhaoyu; ...

2017-06-01

How photoexcitations evolve into Coulomb-bound electron and hole pairs, called excitons, and unbound charge carriers is a key cross-cutting issue in photovoltaics and optoelectronics. Until now, the initial quantum dynamics following photoexcitation remains elusive in the hybrid perovskite system. Furthermore we reveal excitonic Rydberg states with distinct formation pathways by observing the multiple resonant, internal quantum transitions using ultrafast terahertz quasi-particle transport. Nonequilibrium emergent states evolve with a complex co-existence of excitons, carriers and phonons, where a delayed buildup of excitons under on- and off-resonant pumping conditions allows us to distinguish between the loss of electronic coherence and hot statemore » cooling processes. The nearly ~1 ps dephasing time, efficient electron scattering with discrete terahertz phonons and intermediate binding energy of ~13.5 meV in perovskites are distinct from conventional photovoltaic semiconductors. In addition to providing implications for coherent energy conversion, these are potentially relevant to the development of light-harvesting and electron-transport devices.« less

Multifaceted Leptin network: the molecular connection between obesity and breast cancer

PubMed Central

Saxena, Neeraj K.; Sharma, Dipali

2016-01-01

High plasma levels of leptin, a major adipocytokine produced by adipocytes, are correlated with increased fat mass in obese state. Leptin is emerging as a key candidate molecule linking obesity with breast cancer. Acting via endocrine, paracrine, and autocrine manner, leptin impacts various stages of breast tumorigenesis from initiation and primary tumor growth to metastatic progression. Leptin also modulates the tumor microenvironment mainly through supporting migration of endothelial cells, neo-angiogenesis and sustaining recruitment of macrophage and monocytes. Various studies have shown that hyperactive leptin-signaling network leads to concurrent activation of multiple oncogenic pathways resulting in enhanced proliferation, decreased apoptosis, acquisition of mesenchymal phenotype, potentiated migration and enhanced invasion potential of tumor cells. Furthermore, the capability of leptin to interact with other molecular effectors of obese state including, estrogen, IGF-1, insulin, VEGF and inflammatory cytokines further increases its impact on breast tumor progression in obese state. This article presents an overview of the studies investigating the involvement of leptin in breast cancer. PMID:24214584

Raf kinase inhibitory protein: a signal transduction modulator and metastasis suppressor.

PubMed

Granovsky, Alexey E; Rosner, Marsha Rich

2008-04-01

Cells have a multitude of controls to maintain their integrity and prevent random switching from one biological state to another. Raf Kinase Inhibitory Protein (RKIP), a member of the phosphatidylethanolamine binding protein (PEBP) family, is representative of a new class of modulators of signaling cascades that function to maintain the "yin yang" or balance of biological systems. RKIP inhibits MAP kinase (Raf-MEK-ERK), G protein-coupled receptor (GPCR) kinase and NFkappaB signaling cascades. Because RKIP targets different kinases dependent upon its state of phosphorylation, RKIP also acts to integrate crosstalk initiated by multiple environmental stimuli. Loss or depletion of RKIP results in disruption of the normal cellular stasis and can lead to chromosomal abnormalities and disease states such as cancer. Since RKIP and the PEBP family have been reviewed previously, the goal of this analysis is to provide an update and highlight some of the unique features of RKIP that make it a critical player in the regulation of cellular signaling processes.

Ultrafast terahertz snapshots of excitonic Rydberg states and electronic coherence in an organometal halide perovskite

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

Luo, Liang; Men, Long; Liu, Zhaoyu

How photoexcitations evolve into Coulomb-bound electron and hole pairs, called excitons, and unbound charge carriers is a key cross-cutting issue in photovoltaics and optoelectronics. Until now, the initial quantum dynamics following photoexcitation remains elusive in the hybrid perovskite system. Furthermore we reveal excitonic Rydberg states with distinct formation pathways by observing the multiple resonant, internal quantum transitions using ultrafast terahertz quasi-particle transport. Nonequilibrium emergent states evolve with a complex co-existence of excitons, carriers and phonons, where a delayed buildup of excitons under on- and off-resonant pumping conditions allows us to distinguish between the loss of electronic coherence and hot statemore » cooling processes. The nearly ~1 ps dephasing time, efficient electron scattering with discrete terahertz phonons and intermediate binding energy of ~13.5 meV in perovskites are distinct from conventional photovoltaic semiconductors. In addition to providing implications for coherent energy conversion, these are potentially relevant to the development of light-harvesting and electron-transport devices.« less

Exploring the folding free energy landscape of a β-hairpin miniprotein, chignolin, using multiscale free energy landscape calculation method.

PubMed

Harada, Ryuhei; Kitao, Akio

2011-07-14

The folding process for a β-hairpin miniprotein, chignolin, was investigated by free energy landscape (FEL) calculations using the recently proposed multiscale free energy landscape calculation method (MSFEL). First, coarse-grained molecular dynamics simulations searched a broad conformational space, then multiple independent, all-atom molecular dynamics simulations with explicit solvent determined the detailed local FEL using massively distributed computing. The combination of the two models enabled efficient calculation of the free energy landscapes. The MSFEL analysis showed that chignolin has an intermediate state as well as a misfolded state. The folding process is initiated by the formation of a β-hairpin turn, followed by the formation of contacts in the hydrophobic core between Tyr2 and Trp9. Furthermore, mutation of Tyr2 shifts the population to the misfolded conformation. The results indicate that the hydrophobic core plays an important role in stabilizing the native state of chignolin. © 2011 American Chemical Society

Many-body Quantum Control of a Spin-1 BEC

NASA Astrophysics Data System (ADS)

Hoang, Thai; Anquez, Martin; Robbins, Bryce; Yang, Xiaoyun; Land, Benjamin; Hamley, Christopher; Chapman, Michael

2014-05-01

Spin-1 condensates provide a useful platform for investigations of atom squeezing, generation of non-Gaussian states, and dynamical control. We demonstrate dynamic control of a quantum many-body spin-1 system that is enabled by strong collisional interactions. In contrast to the usual single-particle quantum control techniques, the method demonstrated here is intrinsically many-body, exploiting the strong collisional interactions. The experiment uses a spin-1 87Rb condensate initialized in the | F = 1 , mF = 0 > polar state at a high magnetic field above the quantum phase transition, and then prepared in a coherent state using a rf rotation. The many-body control is implemented by time-varying the relative strength of the Zeeman and spin interaction energies of the condensate at multiples of the natural coherent oscillation frequency of the system. This is a parametric excitation method relying on time varying changes to the Hamiltonian. We will present our experimental results, which compare well to theory, and will discuss future directions and applications.

Consolidation in older adults depends upon competition between resting-state networks

PubMed Central

Jacobs, Heidi I. L.; Dillen, Kim N. H.; Risius, Okka; Göreci, Yasemin; Onur, Oezguer A.; Fink, Gereon R.; Kukolja, Juraj

2015-01-01

Memory encoding and retrieval problems are inherent to aging. To date, however, the effect of aging upon the neural correlates of forming memory traces remains poorly understood. Resting-state fMRI connectivity can be used to investigate initial consolidation. We compared within and between network connectivity differences between healthy young and older participants before encoding, after encoding and before retrieval by means of resting-state fMRI. Alterations over time in the between-network connectivity analyses correlated with retrieval performance, whereas within-network connectivity did not: a higher level of negative coupling or competition between the default mode and the executive networks during the after encoding condition was associated with increased retrieval performance in the older adults, but not in the young group. Data suggest that the effective formation of memory traces depends on an age-dependent, dynamic reorganization of the interaction between multiple, large-scale functional networks. Our findings demonstrate that a cross-network based approach can further the understanding of the neural underpinnings of aging-associated memory decline. PMID:25620930

Abortion in the United States' bible belt: organizing for power and empowerment

PubMed Central

2011-01-01

Over the last 30 years, conservative power in the United States, financed and organized by Christian fundamentalist sects, the Catholic Church, and conservative corporate and political leadership, has become more threatening and potentially destabilizing of progressive democratic principles and practices. Powerful interlocking political, financial and social forces are arrayed against women in many Southern and Western states. They are having destructive effects on women's ability to control their fertility and maintain bodily integrity and health. Poor women and women of color are disproportionately affected by restrictions on abortion services. Strategically developed interventions must be initiated and managed at every level in these localities. It is urgent to coordinate and empower individuals, multiple organizations and communities to engender effective changes in attitudes, norms, behavior and policies that will enable women to obtain reproductive health services, including abortion care. This paper describes contextual factors that continue to decimate U.S. women's right to health and, then, describes a community organizing-social action project in a number of US' states aimed at reversing the erosion of women's right to have or not to have children. PMID:21208420

Abortion in the United States' Bible Belt: organizing for power and empowerment.

PubMed

Castle, Mary Ann

2011-01-05

Over the last 30 years, conservative power in the United States, financed and organized by Christian fundamentalist sects, the Catholic Church, and conservative corporate and political leadership, has become more threatening and potentially destabilizing of progressive democratic principles and practices. Powerful interlocking political, financial and social forces are arrayed against women in many Southern and Western states. They are having destructive effects on women's ability to control their fertility and maintain bodily integrity and health. Poor women and women of color are disproportionately affected by restrictions on abortion services. Strategically developed interventions must be initiated and managed at every level in these localities. It is urgent to coordinate and empower individuals, multiple organizations and communities to engender effective changes in attitudes, norms, behavior and policies that will enable women to obtain reproductive health services, including abortion care. This paper describes contextual factors that continue to decimate U.S. women's right to health and, then, describes a community organizing-social action project in a number of US' states aimed at reversing the erosion of women's right to have or not to have children.

High- and low-risk profiles for the development of multiple sclerosis within 10 years after optic neuritis: experience of the optic neuritis treatment trial.

PubMed

Beck, Roy W; Trobe, Jonathan D; Moke, Pamela S; Gal, Robin L; Xing, Dongyuan; Bhatti, M Tariq; Brodsky, Michael C; Buckley, Edward G; Chrousos, Georgia A; Corbett, James; Eggenberger, Eric; Goodwin, James A; Katz, Barrett; Kaufman, David I; Keltner, John L; Kupersmith, Mark J; Miller, Neil R; Nazarian, Sarkis; Orengo-Nania, Silvia; Savino, Peter J; Shults, William T; Smith, Craig H; Wall, Michael

2003-07-01

To identify factors associated with a high and low risk of developing multiple sclerosis after an initial episode of optic neuritis. Three hundred eighty-eight patients who experienced acute optic neuritis between July 1, 1988, and June 30, 1991, were followed up prospectively for the development of multiple sclerosis. Consenting patients were reassessed after 10 to 13 years. The 10-year risk of multiple sclerosis was 38% (95% confidence interval, 33%-43%). Patients (160) who had 1 or more typical lesions on the baseline magnetic resonance imaging (MRI) scan of the brain had a 56% risk; those with no lesions (191) had a 22% risk (P<.001, log rank test). Among the patients who had no lesions on MRI, male gender and optic disc swelling were associated with a lower risk of multiple sclerosis, as was the presence of the following atypical features for optic neuritis: no light perception vision; absence of pain; and ophthalmoscopic findings of severe optic disc edema, peripapillary hemorrhages, or retinal exudates. The 10-year risk of multiple sclerosis following an initial episode of acute optic neuritis is significantly higher if there is a single brain MRI lesion; higher numbers of lesions do not appreciably increase that risk. However, even when brain lesions are seen on MRI, more than 40% of the patients will not develop clinical multiple sclerosis after 10 years. In the absence of MRI lesions, certain demographic and clinical features seem to predict a very low likelihood of developing multiple sclerosis. This natural history information is a critical input for estimating a patient's 10-year multiple sclerosis risk and for weighing the benefit of initiating prophylactic treatment at the time of optic neuritis or other initial demyelinating events in the central nervous system.

Computational multiple steady states for enzymatic esterification of ethanol and oleic acid in an isothermal CSTR.

PubMed

Ho, Pang-Yen; Chuang, Guo-Syong; Chao, An-Chong; Li, Hsing-Ya

2005-05-01

The capacity of complex biochemical reaction networks (consisting of 11 coupled non-linear ordinary differential equations) to show multiple steady states, was investigated. The system involved esterification of ethanol and oleic acid by lipase in an isothermal continuous stirred tank reactor (CSTR). The Deficiency One Algorithm and the Subnetwork Analysis were applied to determine the steady state multiplicity. A set of rate constants and two corresponding steady states are computed. The phenomena of bistability, hysteresis and bifurcation are discussed. Moreover, the capacity of steady state multiplicity is extended to the family of the studied reaction networks.

Benchmarking in a differentially heated rotating annulus experiment: Multiple equilibria in the light of laboratory experiments and simulations

NASA Astrophysics Data System (ADS)

Vincze, Miklos; Harlander, Uwe; Borchert, Sebastian; Achatz, Ulrich; Baumann, Martin; Egbers, Christoph; Fröhlich, Jochen; Hertel, Claudia; Heuveline, Vincent; Hickel, Stefan; von Larcher, Thomas; Remmler, Sebastian

2014-05-01

In the framework of the German Science Foundation's (DFG) priority program 'MetStröm' various laboratory experiments have been carried out in a differentially heated rotating annulus configuration in order to test, validate and tune numerical methods to be used for modeling large-scale atmospheric processes. This classic experimental set-up is well known since the late 1940s and is a widely studied minimal model of the general mid-latitude atmospheric circulation. The two most relevant factors of cyclogenesis, namely rotation and meridional temperature gradient are quite well captured in this simple arrangement. The tabletop-size rotating tank is divided into three sections by coaxial cylindrical sidewalls. The innermost section is cooled whereas the outermost annular cavity is heated, therefore the working fluid (de-ionized water) in the middle annular section experiences differential heat flow, which imposes thermal (density) stratification on the fluid. At high enough rotation rates the isothermal surfaces tilt, leading to baroclinic instability. The extra potential energy stored in this unstable configuration is then converted into kinetic energy, exciting drifting wave patterns of temperature and momentum anomalies. The signatures of these baroclinic waves at the free water surface have been analysed via infrared thermography in a wide range of rotation rates (keeping the radial temperature difference constant) and under different initial conditions (namely, initial spin-up and "spin-down"). Paralelly to the laboratory simulations of BTU Cottbus-Senftenberg, five other groups from the MetStröm collaboration have conducted simulations in the same parameter regime using different numerical approaches and solvers, and applying different initial conditions and perturbations for stability analysis. The obtained baroclinic wave patterns have been evaluated via determining and comparing their Empirical Orthogonal Functions (EOFs), drift rates and dominant wave modes. Thus certain "benchmarks" have been created that can later be used as test cases for atmospheric numerical model validation. Both in the experiments and in the numerics multiple equilibrium states have been observed in the form of hysteretic behavior depending on the initial conditions. The precise quantification of these state and wave mode transitions may shed light to some aspects of the basic underlying dynamics of the baroclinic annulus configuration, still to be understood.

Synchronization in neural nets

NASA Technical Reports Server (NTRS)

Vidal, Jacques J.; Haggerty, John

1988-01-01

The paper presents an artificial neural network concept (the Synchronizable Oscillator Networks) where the instants of individual firings in the form of point processes constitute the only form of information transmitted between joining neurons. In the model, neurons fire spontaneously and regularly in the absence of perturbation. When interaction is present, the scheduled firings are advanced or delayed by the firing of neighboring neurons. Networks of such neurons become global oscillators which exhibit multiple synchronizing attractors. From arbitrary initial states, energy minimization learning procedures can make the network converge to oscillatory modes that satisfy multi-dimensional constraints. Such networks can directly represent routing and scheduling problems that consist of ordering sequences of events.

Customizing cell signaling using engineered genetic logic circuits.

PubMed

Wang, Baojun; Buck, Martin

2012-08-01

Cells live in an ever-changing environment and continuously sense, process and react to environmental signals using their inherent signaling and gene regulatory networks. Recently, there have been great advances on rewiring the native cell signaling and gene networks to program cells to sense multiple noncognate signals and integrate them in a logical manner before initiating a desired response. Here, we summarize the current state-of-the-art of engineering synthetic genetic logic circuits to customize cellular signaling behaviors, and discuss their promising applications in biocomputing, environmental, biotechnological and biomedical areas as well as the remaining challenges in this growing field. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fluctuation Flooding Method (FFM) for accelerating conformational transitions of proteins.

PubMed

Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

2014-03-28

A powerful conformational sampling method for accelerating structural transitions of proteins, "Fluctuation Flooding Method (FFM)," is proposed. In FFM, cycles of the following steps enhance the transitions: (i) extractions of largely fluctuating snapshots along anisotropic modes obtained from trajectories of multiple independent molecular dynamics (MD) simulations and (ii) conformational re-sampling of the snapshots via re-generations of initial velocities when re-starting MD simulations. In an application to bacteriophage T4 lysozyme, FFM successfully accelerated the open-closed transition with the 6 ns simulation starting solely from the open state, although the 1-μs canonical MD simulation failed to sample such a rare event.

Fluctuation Flooding Method (FFM) for accelerating conformational transitions of proteins

NASA Astrophysics Data System (ADS)

Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

2014-03-01

A powerful conformational sampling method for accelerating structural transitions of proteins, "Fluctuation Flooding Method (FFM)," is proposed. In FFM, cycles of the following steps enhance the transitions: (i) extractions of largely fluctuating snapshots along anisotropic modes obtained from trajectories of multiple independent molecular dynamics (MD) simulations and (ii) conformational re-sampling of the snapshots via re-generations of initial velocities when re-starting MD simulations. In an application to bacteriophage T4 lysozyme, FFM successfully accelerated the open-closed transition with the 6 ns simulation starting solely from the open state, although the 1-μs canonical MD simulation failed to sample such a rare event.

The Kirkwood{endash}Buckingham variational method and the boundary value problems for the molecular Schr{umlt o}dinger equation

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

Pupyshev, V.I.; Scherbinin, A.V.; Stepanov, N.F.

1997-11-01

The approach based on the multiplicative form of a trial wave function within the framework of the variational method, initially proposed by Kirkwood and Buckingham, is shown to be an effective analytical tool in the quantum mechanical study of atoms and molecules. As an example, the elementary proof is given to the fact that the ground state energy of a molecular system placed into the box with walls of finite height goes to the corresponding eigenvalue of the Dirichlet boundary value problem when the height of the walls is growing up to infinity. {copyright} {ital 1997 American Institute of Physics.}

Hysteresis phenomena of the intelligent driver model for traffic flow

NASA Astrophysics Data System (ADS)

Dahui, Wang; Ziqiang, Wei; Ying, Fan

2007-07-01

We present hysteresis phenomena of the intelligent driver model for traffic flow in a circular one-lane roadway. We show that the microscopic structure of traffic flow is dependent on its initial state by plotting the fraction of congested vehicles over the density, which shows a typical hysteresis loop, and by investigating the trajectories of vehicles on the velocity-over-headway plane. We find that the trajectories of vehicles on the velocity-over-headway plane, which usually show a hysteresis loop, include multiple loops. We also point out the relations between these hysteresis loops and the congested jams or high-density clusters in traffic flow.

An Exploratory Multiple-Case Study of the Experiences of Participants in Self-Initiated Peer Support Groups among School Leaders

ERIC Educational Resources Information Center

House, Collette R.

2016-01-01

School leaders commonly face issues of loneliness, isolation, burnout, and depression. The purpose of this qualitative multiple-case study was to explore self-initiated peer support group participation for professional impact and personal impact on school leaders facing issues of loneliness, isolation, stress, and burnout. This study provides an…

Spiral-wave dynamics in ionically realistic mathematical models for human ventricular tissue: the effects of periodic deformation.

PubMed

Nayak, Alok R; Pandit, Rahul

2014-01-01

We carry out an extensive numerical study of the dynamics of spiral waves of electrical activation, in the presence of periodic deformation (PD) in two-dimensional simulation domains, in the biophysically realistic mathematical models of human ventricular tissue due to (a) ten-Tusscher and Panfilov (the TP06 model) and (b) ten-Tusscher, Noble, Noble, and Panfilov (the TNNP04 model). We first consider simulations in cable-type domains, in which we calculate the conduction velocity θ and the wavelength λ of a plane wave; we show that PD leads to a periodic, spatial modulation of θ and a temporally periodic modulation of λ; both these modulations depend on the amplitude and frequency of the PD. We then examine three types of initial conditions for both TP06 and TNNP04 models and show that the imposition of PD leads to a rich variety of spatiotemporal patterns in the transmembrane potential including states with a single rotating spiral (RS) wave, a spiral-turbulence (ST) state with a single meandering spiral, an ST state with multiple broken spirals, and a state SA in which all spirals are absorbed at the boundaries of our simulation domain. We find, for both TP06 and TNNP04 models, that spiral-wave dynamics depends sensitively on the amplitude and frequency of PD and the initial condition. We examine how these different types of spiral-wave states can be eliminated in the presence of PD by the application of low-amplitude pulses by square- and rectangular-mesh suppression techniques. We suggest specific experiments that can test the results of our simulations.

Spiral-wave dynamics in ionically realistic mathematical models for human ventricular tissue: the effects of periodic deformation

PubMed Central

Nayak, Alok R.; Pandit, Rahul

2014-01-01

We carry out an extensive numerical study of the dynamics of spiral waves of electrical activation, in the presence of periodic deformation (PD) in two-dimensional simulation domains, in the biophysically realistic mathematical models of human ventricular tissue due to (a) ten-Tusscher and Panfilov (the TP06 model) and (b) ten-Tusscher, Noble, Noble, and Panfilov (the TNNP04 model). We first consider simulations in cable-type domains, in which we calculate the conduction velocity θ and the wavelength λ of a plane wave; we show that PD leads to a periodic, spatial modulation of θ and a temporally periodic modulation of λ; both these modulations depend on the amplitude and frequency of the PD. We then examine three types of initial conditions for both TP06 and TNNP04 models and show that the imposition of PD leads to a rich variety of spatiotemporal patterns in the transmembrane potential including states with a single rotating spiral (RS) wave, a spiral-turbulence (ST) state with a single meandering spiral, an ST state with multiple broken spirals, and a state SA in which all spirals are absorbed at the boundaries of our simulation domain. We find, for both TP06 and TNNP04 models, that spiral-wave dynamics depends sensitively on the amplitude and frequency of PD and the initial condition. We examine how these different types of spiral-wave states can be eliminated in the presence of PD by the application of low-amplitude pulses by square- and rectangular-mesh suppression techniques. We suggest specific experiments that can test the results of our simulations. PMID:24959148

Methods used to parameterize the spatially-explicit components of a state-and-transition simulation model

USGS Publications Warehouse

Sleeter, Rachel; Acevedo, William; Soulard, Christopher E.; Sleeter, Benjamin M.

2015-01-01

Spatially-explicit state-and-transition simulation models of land use and land cover (LULC) increase our ability to assess regional landscape characteristics and associated carbon dynamics across multiple scenarios. By characterizing appropriate spatial attributes such as forest age and land-use distribution, a state-and-transition model can more effectively simulate the pattern and spread of LULC changes. This manuscript describes the methods and input parameters of the Land Use and Carbon Scenario Simulator (LUCAS), a customized state-and-transition simulation model utilized to assess the relative impacts of LULC on carbon stocks for the conterminous U.S. The methods and input parameters are spatially explicit and describe initial conditions (strata, state classes and forest age), spatial multipliers, and carbon stock density. Initial conditions were derived from harmonization of multi-temporal data characterizing changes in land use as well as land cover. Harmonization combines numerous national-level datasets through a cell-based data fusion process to generate maps of primary LULC categories. Forest age was parameterized using data from the North American Carbon Program and spatially-explicit maps showing the locations of past disturbances (i.e. wildfire and harvest). Spatial multipliers were developed to spatially constrain the location of future LULC transitions. Based on distance-decay theory, maps were generated to guide the placement of changes related to forest harvest, agricultural intensification/extensification, and urbanization. We analyze the spatially-explicit input parameters with a sensitivity analysis, by showing how LUCAS responds to variations in the model input. This manuscript uses Mediterranean California as a regional subset to highlight local to regional aspects of land change, which demonstrates the utility of LUCAS at many scales and applications.

Exponential Sensitivity and its Cost in Quantum Physics

PubMed Central

Gilyén, András; Kiss, Tamás; Jex, Igor

2016-01-01

State selective protocols, like entanglement purification, lead to an essentially non-linear quantum evolution, unusual in naturally occurring quantum processes. Sensitivity to initial states in quantum systems, stemming from such non-linear dynamics, is a promising perspective for applications. Here we demonstrate that chaotic behaviour is a rather generic feature in state selective protocols: exponential sensitivity can exist for all initial states in an experimentally realisable optical scheme. Moreover, any complex rational polynomial map, including the example of the Mandelbrot set, can be directly realised. In state selective protocols, one needs an ensemble of initial states, the size of which decreases with each iteration. We prove that exponential sensitivity to initial states in any quantum system has to be related to downsizing the initial ensemble also exponentially. Our results show that magnifying initial differences of quantum states (a Schrödinger microscope) is possible; however, there is a strict bound on the number of copies needed. PMID:26861076

Exponential Sensitivity and its Cost in Quantum Physics.

PubMed

Gilyén, András; Kiss, Tamás; Jex, Igor

2016-02-10

State selective protocols, like entanglement purification, lead to an essentially non-linear quantum evolution, unusual in naturally occurring quantum processes. Sensitivity to initial states in quantum systems, stemming from such non-linear dynamics, is a promising perspective for applications. Here we demonstrate that chaotic behaviour is a rather generic feature in state selective protocols: exponential sensitivity can exist for all initial states in an experimentally realisable optical scheme. Moreover, any complex rational polynomial map, including the example of the Mandelbrot set, can be directly realised. In state selective protocols, one needs an ensemble of initial states, the size of which decreases with each iteration. We prove that exponential sensitivity to initial states in any quantum system has to be related to downsizing the initial ensemble also exponentially. Our results show that magnifying initial differences of quantum states (a Schrödinger microscope) is possible; however, there is a strict bound on the number of copies needed.

Surface-Enhanced Raman Optical Data Storage system

DOEpatents

Vo-Dinh, T.

1994-06-28

An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level. 18 figures.

Surface-enhanced raman optical data storage system

DOEpatents

Vo-Dinh, Tuan

1994-01-01

An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level.

75 FR 79419 - Training and Employment Guidance (TEGL) Letter No. 13-10: Fiscal Year (FY) 2011 State Initial...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-20

...) Letter No. 13-10: Fiscal Year (FY) 2011 State Initial Allocations and the Process for Requesting...-10 entitled, FY 2011 State Initial Allocations and the Process for Requesting Additional TAA Program... INFORMATION: Fiscal Year (FY) 2011 State Initial Allocations and the Process for Requesting Additional Trade...

Consumer Satisfaction in Long-Term Care: State Initiatives in Nursing Homes and Assisted Living Facilities

ERIC Educational Resources Information Center

Lowe, Timothy J.; Lucas, Judith A.; Castle, Nicholas G.; Robinson, Joanne P.; Crystal, Stephen

2003-01-01

Purpose: We report the results of a survey of state initiatives that measure resident satisfaction in nursing homes and assisted living facilities, and we describe several model programs for legislators and public administrators contemplating the initiation of their own state programs. Design and Methods: Data on state initiatives and programs…

Assisting People with Multiple Disabilities to Use Computers with Multiple Mice

ERIC Educational Resources Information Center

Shih, Ching-Hsiang; Shih, Ching-Tien

2009-01-01

This study assessed the combination of multiple mice aid with two persons with multiple disabilities. Complete mouse operation which needed the physically functional sound, was distributed among their limbs with remaining ability. Through these decentralized operations, they could still reach complete mouse pointing control. Initially, both…

West Nile virus: a primer for the otolaryngologist.

PubMed

Michaelson, Peter G; Mair, Eric A

2005-03-01

Since recognition in the United States with a 1999 New York City epidemic, West Nile virus has enduringly migrated westward, leaving few states unaffected. Infection rates are rising at an alarming rate, doubling every year since introduction, with more than 9800 cases in 2003 alone and more than 260 deaths. Patients may present with myriad symptoms including a maculopapular rash that affects the face and trunk and diffuse lymphadenopathy, both of which may result in the initial consultation of the otolaryngologist. We review the clinical history of West Nile virus and its epidemiology, laboratory findings, and variable clinical presentation, with an emphasis on otolaryngologic manifestations. STUDY DESIGN AND SETTING COMPREHENSIVE: review of the literature over the past 50 years with an emphasis on what the present-day otolaryngologist needs to know concerning West Nile virus. Clinical manifestations of the head and neck such as encephalitis, meningitis, maculopapular rash, lymphadenopathy and dysphagia are discussed. To date, there are no articles in the otolaryngology literature discussing West Nile virus. These patients may present initially to multiple providers in diverse specialties because of multifarious initial signs and symptoms. The otolaryngologist must be educated on this quickly growing affliction and practice with a high index of suspicion. In this article we describe the clinical manifestations of West Nile virus, with an emphasis on the otolaryngologic manifestations. The otolaryngologist must become educated about this entity to facilitate preventative measures, adequately treat, and assist other providers in hopeful control and potential eradication of this infectious threat.

Multiple switching modes and multiple level states in memristive devices

NASA Astrophysics Data System (ADS)

Miao, Feng; Yang, J. Joshua; Borghetti, Julien; Strachan, John Paul; Zhang, M.-X.; Goldfarb, Ilan; Medeiros-Ribeiro, Gilberto; Williams, R. Stanley

2011-03-01

As one of the most promising technologies for next generation non-volatile memory, metal oxide based memristive devices have demonstrated great advantages on scalability, operating speed and power consumption. Here we report the observation of multiple switching modes and multiple level states in different memristive systems. The multiple switching modes can be obtained by limiting the current during electroforming, and related transport behaviors, including ionic and electronic motions, are characterized. Such observation can be rationalized by a model of two effective switching layers adjacent to the bottom and top electrodes. Multiple level states, corresponding to different composition of the conducting channel, will also be discussed in the context of multiple-level storage for high density, non-volatile memory applications.

Prediction of hearing outcomes by multiple regression analysis in patients with idiopathic sudden sensorineural hearing loss.

PubMed

Suzuki, Hideaki; Tabata, Takahisa; Koizumi, Hiroki; Hohchi, Nobusuke; Takeuchi, Shoko; Kitamura, Takuro; Fujino, Yoshihisa; Ohbuchi, Toyoaki

2014-12-01

This study aimed to create a multiple regression model for predicting hearing outcomes of idiopathic sudden sensorineural hearing loss (ISSNHL). The participants were 205 consecutive patients (205 ears) with ISSNHL (hearing level ≥ 40 dB, interval between onset and treatment ≤ 30 days). They received systemic steroid administration combined with intratympanic steroid injection. Data were examined by simple and multiple regression analyses. Three hearing indices (percentage hearing improvement, hearing gain, and posttreatment hearing level [HLpost]) and 7 prognostic factors (age, days from onset to treatment, initial hearing level, initial hearing level at low frequencies, initial hearing level at high frequencies, presence of vertigo, and contralateral hearing level) were included in the multiple regression analysis as dependent and explanatory variables, respectively. In the simple regression analysis, the percentage hearing improvement, hearing gain, and HLpost showed significant correlation with 2, 5, and 6 of the 7 prognostic factors, respectively. The multiple correlation coefficients were 0.396, 0.503, and 0.714 for the percentage hearing improvement, hearing gain, and HLpost, respectively. Predicted values of HLpost calculated by the multiple regression equation were reliable with 70% probability with a 40-dB-width prediction interval. Prediction of HLpost by the multiple regression model may be useful to estimate the hearing prognosis of ISSNHL. © The Author(s) 2014.

Intrinsic functional component analysis via sparse representation on Alzheimer's disease neuroimaging initiative database.

PubMed

Jiang, Xi; Zhang, Xin; Zhu, Dajiang

2014-10-01

Alzheimer's disease (AD) is the most common type of dementia (accounting for 60% to 80%) and is the fifth leading cause of death for those people who are 65 or older. By 2050, one new case of AD in United States is expected to develop every 33 sec. Unfortunately, there is no available effective treatment that can stop or slow the death of neurons that causes AD symptoms. On the other hand, it is widely believed that AD starts before development of the associated symptoms, so its prestages, including mild cognitive impairment (MCI) or even significant memory concern (SMC), have received increasing attention, not only because of their potential as a precursor of AD, but also as a possible predictor of conversion to other neurodegenerative diseases. Although these prestages have been defined clinically, accurate/efficient diagnosis is still challenging. Moreover, brain functional abnormalities behind those alterations and conversions are still unclear. In this article, by developing novel sparse representations of whole-brain resting-state functional magnetic resonance imaging signals and by using the most updated Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset, we successfully identified multiple functional components simultaneously, and which potentially represent those intrinsic functional networks involved in the resting-state activities. Interestingly, these identified functional components contain all the resting-state networks obtained from traditional independent-component analysis. Moreover, by using the features derived from those functional components, it yields high classification accuracy for both AD (94%) and MCI (92%) versus normal controls. Even for SMC we can still have 92% accuracy.

Creating Weather System Ensembles Through Synergistic Process Modeling and Machine Learning

NASA Astrophysics Data System (ADS)

Chen, B.; Posselt, D. J.; Nguyen, H.; Wu, L.; Su, H.; Braverman, A. J.

2017-12-01

Earth's weather and climate are sensitive to a variety of control factors (e.g., initial state, forcing functions, etc). Characterizing the response of the atmosphere to a change in initial conditions or model forcing is critical for weather forecasting (ensemble prediction) and climate change assessment. Input - response relationships can be quantified by generating an ensemble of multiple (100s to 1000s) realistic realizations of weather and climate states. Atmospheric numerical models generate simulated data through discretized numerical approximation of the partial differential equations (PDEs) governing the underlying physics. However, the computational expense of running high resolution atmospheric state models makes generation of more than a few simulations infeasible. Here, we discuss an experiment wherein we approximate the numerical PDE solver within the Weather Research and Forecasting (WRF) Model using neural networks trained on a subset of model run outputs. Once trained, these neural nets can produce large number of realization of weather states from a small number of deterministic simulations with speeds that are orders of magnitude faster than the underlying PDE solver. Our neural network architecture is inspired by the governing partial differential equations. These equations are location-invariant, and consist of first and second derivations. As such, we use a 3x3 lon-lat grid of atmospheric profiles as the predictor in the neural net to provide the network the information necessary to compute the first and second moments. Results indicate that the neural network algorithm can approximate the PDE outputs with high degree of accuracy (less than 1% error), and that this error increases as a function of the prediction time lag.

Influence of Ambient Humidity on the Voltage Response of Ionic Polymer-Metal Composite Sensor.

PubMed

Zhu, Zicai; Horiuchi, Tetsuya; Kruusamäe, Karl; Chang, Longfei; Asaka, Kinji

2016-03-31

Electrical potential based on ion migration exists not only in natural systems but also in ionic polymer materials. In order to investigate the influence of ambient humidity on voltage response, classical Au-Nafion IPMC was chosen as the reference sample. Voltage response under a bending deformation was measured in two ways: first, continuous measurement of voltage response in the process of absorption and desorption of water to study the tendency of voltage variation at all water states; second, measurements at multiple fixed ambient humidity levels to characterize the process of voltage response quantitatively. Ambient humidity influences the voltage response mainly by varying water content in ionic polymer. Under a step bending, the amplitude of initial voltage peak first increases and then decreases as the ambient humidity and the inherent water content decrease. This tendency is explained semiquantitatively by mass storage capacity related to the stretchable state of the Nafion polymer network. Following the initial peak, the voltage shows a slow decay to a steady state, which is first characterized in this paper. The relative voltage decay during the steady state always decreases as the ambient humidity is lowered. It is ascribed to progressive increase of the ratio between the water molecules in the cation hydration shell to the free water. Under sinusoidal mechanical bending excitation in the range of 0.1-10 Hz, the voltage magnitude increases with frequency at high ambient humidity but decreases with frequency at low ambient humidity. The relationship is mainly controlled by the voltage decay effect and the response speed.

Self-balancing dynamic scheduling of electrical energy for energy-intensive enterprises

NASA Astrophysics Data System (ADS)

Gao, Yunlong; Gao, Feng; Zhai, Qiaozhu; Guan, Xiaohong

2013-06-01

Balancing production and consumption with self-generation capacity in energy-intensive enterprises has huge economic and environmental benefits. However, balancing production and consumption with self-generation capacity is a challenging task since the energy production and consumption must be balanced in real time with the criteria specified by power grid. In this article, a mathematical model for minimising the production cost with exactly realisable energy delivery schedule is formulated. And a dynamic programming (DP)-based self-balancing dynamic scheduling algorithm is developed to obtain the complete solution set for such a multiple optimal solutions problem. For each stage, a set of conditions are established to determine whether a feasible control trajectory exists. The state space under these conditions is partitioned into subsets and each subset is viewed as an aggregate state, the cost-to-go function is then expressed as a function of initial and terminal generation levels of each stage and is proved to be a staircase function with finite steps. This avoids the calculation of the cost-to-go of every state to resolve the issue of dimensionality in DP algorithm. In the backward sweep process of the algorithm, an optimal policy is determined to maximise the realisability of energy delivery schedule across the entire time horizon. And then in the forward sweep process, the feasible region of the optimal policy with the initial and terminal state at each stage is identified. Different feasible control trajectories can be identified based on the region; therefore, optimising for the feasible control trajectory is performed based on the region with economic and reliability objectives taken into account.

The transition of dynamic rupture styles in elastic media under velocity-weakening friction

NASA Astrophysics Data System (ADS)

Gabriel, A.-A.; Ampuero, J.-P.; Dalguer, L. A.; Mai, P. M.

2012-09-01

Although kinematic earthquake source inversions show dominantly pulse-like subshear rupture behavior, seismological observations, laboratory experiments and theoretical models indicate that earthquakes can operate with different rupture styles: either as pulses or cracks, that propagate at subshear or supershear speeds. The determination of rupture style and speed has important implications for ground motions and may inform about the state of stress and strength of active fault zones. We conduct 2D in-plane dynamic rupture simulations with a spectral element method to investigate the diversity of rupture styles on faults governed by velocity-and-state-dependent friction with dramatic velocity-weakening at high slip rate. Our rupture models are governed by uniform initial stresses, and are artificially initiated. We identify the conditions that lead to different rupture styles by investigating the transitions between decaying, steady state and growing pulses, cracks, sub-shear and super-shear ruptures as a function of background stress, nucleation size and characteristic velocity at the onset of severe weakening. Our models show that small changes of background stress or nucleation size may lead to dramatic changes of rupture style. We characterize the asymptotic properties of steady state and self-similar pulses as a function of background stress. We show that an earthquake may not be restricted to a single rupture style, but that complex rupture patterns may emerge that consist of multiple rupture fronts, possibly involving different styles and back-propagating fronts. We also demonstrate the possibility of a super-shear transition for pulse-like ruptures. Finally, we draw connections between our findings and recent seismological observations.

Increasing atmospheric CO2 overrides the historical legacy of multiple stable biome states in Africa.

PubMed

Moncrieff, Glenn R; Scheiter, Simon; Bond, William J; Higgins, Steven I

2014-02-01

The dominant vegetation over much of the global land surface is not predetermined by contemporary climate, but also influenced by past environmental conditions. This confounds attempts to predict current and future biome distributions, because even a perfect model would project multiple possible biomes without knowledge of the historical vegetation state. Here we compare the distribution of tree- and grass-dominated biomes across Africa simulated using a dynamic global vegetation model (DGVM). We explicitly evaluate where and under what conditions multiple stable biome states are possible for current and projected future climates. Our simulation results show that multiple stable biomes states are possible for vast areas of tropical and subtropical Africa under current conditions. Widespread loss of the potential for multiple stable biomes states is projected in the 21st Century, driven by increasing atmospheric CO2 . Many sites where currently both tree-dominated and grass-dominated biomes are possible become deterministically tree-dominated. Regions with multiple stable biome states are widespread and require consideration when attempting to predict future vegetation changes. Testing for behaviour characteristic of systems with multiple stable equilibria, such as hysteresis and dependence on historical conditions, and the resulting uncertainty in simulated vegetation, will lead to improved projections of global change impacts. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

The initial rise method extended to multiple trapping levels in thermoluminescent materials.

PubMed

Furetta, C; Guzmán, S; Ruiz, B; Cruz-Zaragoza, E

2011-02-01

The well known Initial Rise Method (IR) is commonly used to determine the activation energy when only one glow peak is presented and analysed in the phosphor materials. However, when the glow peak is more complex, a wide peak and some holders appear in the structure. The application of the Initial Rise Method is not valid because multiple trapping levels are considered and then the thermoluminescent analysis becomes difficult to perform. This paper shows the case of a complex glow curve structure as an example and shows that the calculation is also possible using the IR method. The aim of the paper is to extend the well known Initial Rise Method (IR) to the case of multiple trapping levels. The IR method is applied to minerals extracted from Nopal cactus and Oregano spices because the thermoluminescent glow curve's shape suggests a trap distribution instead of a single trapping level. Copyright © 2010 Elsevier Ltd. All rights reserved.

Toward optimizing the delivery and use of climate science for natural resource management: lessons learned from recent adaptation efforts in the southwestern U.S.

NASA Astrophysics Data System (ADS)

Enquist, C.

2014-12-01

Within the past decade, a wealth of federal, state, and NGO-driven initiatives has emerged across managed landscapes in the United States with the goal of facilitating a coordinated response to rapidly changing climate and environmental conditions. In addition to acquisition and translation of the latest climate science, climate vulnerability assessment and scenario planning at multiple spatial and temporal scales are typically major components of such broad adaptation efforts. Numerous approaches for conducting this work have emerged in recent years and have culminated in general guidance and trainings for resource professionals that are specifically designed to help practitioners face the challenges of climate change. In particular, early engagement of stakeholders across multiple jurisdictions is particularly critical to cultivate buy-in and other enabling conditions for moving the science to on-the-ground action. I report on a suite of adaptation efforts in the southwestern US and interior Rockies, highlighting processes used, actions taken, lessons learned, and recommended next steps to facilitate achieving desired management outcomes. This includes a discussion of current efforts to optimize funding for actionable climate science, formalize science-management collaborations, and facilitate new investments in approaches for strategic climate-informed monitoring and evaluation.

Track Everything: Limiting Prior Knowledge in Online Multi-Object Recognition.

PubMed

Wong, Sebastien C; Stamatescu, Victor; Gatt, Adam; Kearney, David; Lee, Ivan; McDonnell, Mark D

2017-10-01

This paper addresses the problem of online tracking and classification of multiple objects in an image sequence. Our proposed solution is to first track all objects in the scene without relying on object-specific prior knowledge, which in other systems can take the form of hand-crafted features or user-based track initialization. We then classify the tracked objects with a fast-learning image classifier, that is based on a shallow convolutional neural network architecture and demonstrate that object recognition improves when this is combined with object state information from the tracking algorithm. We argue that by transferring the use of prior knowledge from the detection and tracking stages to the classification stage, we can design a robust, general purpose object recognition system with the ability to detect and track a variety of object types. We describe our biologically inspired implementation, which adaptively learns the shape and motion of tracked objects, and apply it to the Neovision2 Tower benchmark data set, which contains multiple object types. An experimental evaluation demonstrates that our approach is competitive with the state-of-the-art video object recognition systems that do make use of object-specific prior knowledge in detection and tracking, while providing additional practical advantages by virtue of its generality.

Implementing Health and Safety Policy Changes at the High School Level From a Leadership Perspective

PubMed Central

Pagnotta, Kelly D.; Mazerolle, Stephanie M.; Pitney, William A.; Burton, Laura J.; Casa, Douglas J.

2016-01-01

Context:  Although consensus statements and recommendations from professional organizations aim to reduce the incidence of injury or sudden death in sport, nothing is mandated at the high school level. This allows states the freedom to create and implement individual policies. An example of a recommended policy is heat acclimatization. Despite its efficacy in reducing sudden death related to heat stroke, very few states follow the recommended guidelines. Objective:  To retroactively examine why and how 3 states were able to facilitate the successful creation and adoption of heat-acclimatization guidelines. Design:  Qualitative study. Setting:  High school athletic associations in Arkansas, Georgia, and New Jersey. Patients or Other Participants:  Eight men and 3 women (n = 11; 6 athletic trainers; 2 members of high school athletic associations; 2 parents; 1 physician) participated. Participant recruitment ceased when data saturation was reached. Data Collection and Analysis:  All phone interviews were digitally recorded and transcribed verbatim. A grounded-theory approach guided analysis and multiple analysts and peer review were used to establish credibility. Results:  Each state had a different catalyst to change (student-athlete death, empirical data, proactivity). Recommendations from national governing bodies guided the policy creation. Once the decision to implement change was made, the states displayed 2 similarities: shared leadership and open communication between medical professionals and members of the high school athletic association helped overcome barriers. Conclusions:  The initiating factor that spurred the change varied, yet shared leadership and communication fundamentally allowed for successful adoption of the policy. Our participants were influenced by the recommendations from national governing bodies, which align with the institutional change theory. As more states begin to examine and improve their health and safety policies, this information could serve as a valuable resource for athletic trainers in other states and for future health and safety initiatives. PMID:27002250

Evaluating and Understanding Parameterized Convective Processes and their Role in the Development of Mesoscale Precipitation Systems

NASA Technical Reports Server (NTRS)

Fritsch, J. Michael; Kain, John S.

1997-01-01

Research efforts during the second year have centered on improving the manner in which convective stabilization is achieved in the Penn State/NCAR mesoscale model MM5. Ways of improving this stabilization have been investigated by (1) refining the partitioning between the Kain-Fritsch convective parameterization scheme and the grid scale by introducing a form of moist convective adjustment; (2) using radar data to define locations of subgrid-scale convection during a dynamic initialization period; and (3) parameterizing deep-convective feedbacks as subgrid-scale sources and sinks of mass. These investigations were conducted by simulating a long-lived convectively-generated mesoscale vortex that occurred during 14-18 Jul. 1982 and the 10-11 Jun. 1985 squall line that occurred over the Kansas-Oklahoma region during the PRE-STORM experiment. The long-lived vortex tracked across the central Plains states and was responsible for multiple convective outbreaks during its lifetime.

Charge-Transfer Processes in Warm Dense Matter: Selective Spectral Filtering for Laser-Accelerated Ion Beams

NASA Astrophysics Data System (ADS)

Braenzel, J.; Barriga-Carrasco, M. D.; Morales, R.; Schnürer, M.

2018-05-01

We investigate, both experimentally and theoretically, how the spectral distribution of laser accelerated carbon ions can be filtered by charge exchange processes in a double foil target setup. Carbon ions at multiple charge states with an initially wide kinetic energy spectrum, from 0.1 to 18 MeV, were detected with a remarkably narrow spectral bandwidth after they had passed through an ultrathin and partially ionized foil. With our theoretical calculations, we demonstrate that this process is a consequence of the evolution of the carbon ion charge states in the second foil. We calculated the resulting spectral distribution separately for each ion species by solving the rate equations for electron loss and capture processes within a collisional radiative model. We determine how the efficiency of charge transfer processes can be manipulated by controlling the ionization degree of the transfer matter.

Growth of a Pharmacy School Through Planning, Cooperation, and Establishment of a Satellite Campus

PubMed Central

Roffman, David S.; Cooper, William J.

2009-01-01

University of Maryland School of Pharmacy was in a quandary: its comprehensive mission required meeting state workforce needs while increasing educational quality, expanding research, and responding to service needs, but state resources were declining, faculty members were stressed, construction of a long-needed new building was stalled, and pressure to increase doctor of pharmacy (PharmD) enrollment was growing. A sharp challenge from the Board of Regents mobilized the school to quickly launch a growth initiative to accelerate PharmD program expansion through a satellite campus. Within 4 months, a plan was approved that not only led to enrollment growth, but also to a significant expansion of the faculty and staff, increased operating and capital budgets, and ground breaking for an $83 million new building. This case study illustrates how seemingly competitive needs such as teaching, research, and service can be woven together synergistically to accomplish multiple goals. PMID:19885071

National nursing science priorities: Creating a shared vision.

PubMed

Eckardt, Patricia; Culley, Joan M; Corwin, Elizabeth; Richmond, Therese; Dougherty, Cynthia; Pickler, Rita H; Krause-Parello, Cheryl A; Roye, Carol F; Rainbow, Jessica G; DeVon, Holli A

Nursing science is essential to advance population health through contributions at all phases of scientific inquiry. Multiple scientific initiatives important to nursing science overlap in aims and population focus. This article focused on providing the American Academy of Nursing and nurse scientists in the Unites States with a blueprint of nursing science priorities to inform a shared vision for future collaborations, areas of scientific inquiry, and resource allocation. The Science Committee convened four times and using Delphi methods identified priorities with empirical evidence and expert opinion for prioritization, state of the science, expert interest, and potential target stakeholders. Nursing science priorities for 2017 were categorized into four themes including: (a) precision science, (b) big data and data analytics, (c) determinants of health, and (d) global health. Nurse scientists can generate new knowledge in priority areas that advances the health of the world's populations. Copyright © 2017 Elsevier Inc. All rights reserved.

Synthetic Vision System Commercial Aircraft Flight Deck Display Technologies for Unusual Attitude Recovery

NASA Technical Reports Server (NTRS)

Prinzel, Lawrence J., III; Ellis, Kyle E.; Arthur, Jarvis J.; Nicholas, Stephanie N.; Kiggins, Daniel

2017-01-01

A Commercial Aviation Safety Team (CAST) study of 18 worldwide loss-of-control accidents and incidents determined that the lack of external visual references was associated with a flight crew's loss of attitude awareness or energy state awareness in 17 of these events. Therefore, CAST recommended development and implementation of virtual day-Visual Meteorological Condition (VMC) display systems, such as synthetic vision systems, which can promote flight crew attitude awareness similar to a day-VMC environment. This paper describes the results of a high-fidelity, large transport aircraft simulation experiment that evaluated virtual day-VMC displays and a "background attitude indicator" concept as an aid to pilots in recovery from unusual attitudes. Twelve commercial airline pilots performed multiple unusual attitude recoveries and both quantitative and qualitative dependent measures were collected. Experimental results and future research directions under this CAST initiative and the NASA "Technologies for Airplane State Awareness" research project are described.

Effects of Multiple Planning Constraints on the Development of Grasp Posture Planning in 6- to 10-Year-Old Children

ERIC Educational Resources Information Center

Stöckel, Tino; Hughes, Charmayne M. L.

2015-01-01

This experiment examined how multiple planning constraints affect grasp posture planning in 6- to 10-year-old children (n = 16 in each group) by manipulating the intended object end-orientation (left end-down, right end-down) and initial precision demands (standard, initial precision) of a bar transport task. Results indicated that grasp posture…

USArray Receiver Function Imaging of Multiple-Layer Crustal Structure of the Contiguous United States

NASA Astrophysics Data System (ADS)

Ma, X.; Lowry, A. R.; Ravat, D.

2014-12-01

Thickness andseismic velocity of crustal layers are useful for understanding the history and evolution of continental lithosphere. Lowry and Pérez-Gussinyé (2011) observed that low bulk crustal seismic velocity ratio, Vp/Vs, strongly correlates with high geothermal gradient and active deformation, indicating quartz (to which Vp/Vs is most sensitive) plays a role in these processes. The lower crust (where ductile flow occurs which might explain the relationship) is commonly thought to be quartz-poor. However, layering of the crust may represent changes in either lithology or the phase of quartz. Laboratory strain-stress experiments on quartz indicate that near the a- to b-quartz phase transition, both Vp and Vp/Vs initially drop dramatically but then increase relative to the a-quartz regime because Young's modulus initially decreases by 30% before increasing by a net ~20%. Shear modulus varies only ~3% across the transition. Crustal structure is commonly represented by an upper, mid- and lower layer (e.g., Crust1.0) and conceptualized as primarily reflecting a change to more mafic lithology at greater depth, but estimates of Moho temperature indicate a quartz phase transition should be present in much of the western and central U.S. We have imaged multiple layering of the contiguous U.S. by applying a new cross-correlation and stacking method to USArray receiver functions. Synthetic models of a multiple layer crust indicate 'splitting' of converted-phase arrivals would be expected if a quartz phase transition were responsible. Preliminary imaging using cross-correlation of observed receiver functions with multiple layer synthetics demonstrates a marked improvement in correlation coefficients relative to a single-layer crust. In this presentation we will examine observational evidence for possible a- to b- phase transition layering (indicating quartz at depth) and compare with depths predicted for the quartz phase transition based on Pn-derived Moho temperatures and estimates of magnetic Curie depths.

A Class of Manifold Regularized Multiplicative Update Algorithms for Image Clustering.

PubMed

Yang, Shangming; Yi, Zhang; He, Xiaofei; Li, Xuelong

2015-12-01

Multiplicative update algorithms are important tools for information retrieval, image processing, and pattern recognition. However, when the graph regularization is added to the cost function, different classes of sample data may be mapped to the same subspace, which leads to the increase of data clustering error rate. In this paper, an improved nonnegative matrix factorization (NMF) cost function is introduced. Based on the cost function, a class of novel graph regularized NMF algorithms is developed, which results in a class of extended multiplicative update algorithms with manifold structure regularization. Analysis shows that in the learning, the proposed algorithms can efficiently minimize the rank of the data representation matrix. Theoretical results presented in this paper are confirmed by simulations. For different initializations and data sets, variation curves of cost functions and decomposition data are presented to show the convergence features of the proposed update rules. Basis images, reconstructed images, and clustering results are utilized to present the efficiency of the new algorithms. Last, the clustering accuracies of different algorithms are also investigated, which shows that the proposed algorithms can achieve state-of-the-art performance in applications of image clustering.

[Utility of conceptual schemes and mental maps on the teaching-learning process of residents in pediatrics].

PubMed

Cruza, Norberto Sotelo; Fierros, Luis E

2006-01-01

The present study was done at the internal medicine service oft he Hospital lnfantil in the State of Sonora, Mexico. We tried to address the question of the use of conceptual schemes and mind maps and its impact on the teaching-learning-evaluation process among medical residents. Analyze the effects of conceptual schemes, and mind maps as a teaching and evaluation tool and compare them with multiple choice exams among Pediatric residents. Twenty two residents (RI, RII, RIII)on service rotation during six months were assessed initially, followed by a lecture on a medical subject. Conceptual schemes and mind maps were then introduced as a teaching-learning-evaluation instrument. Comprehension impact and comparison with a standard multiple choice evaluation was done. The statistical package (JMP version 5, SAS inst. 2004) was used. We noted that when we used conceptual schemes and mind mapping, learning improvement was noticeable among the three groups of residents (P < 0.001) and constitutes a better evaluation tool when compared with multiple choice exams (P < 0.0005). Based on our experience we recommend the use of this educational technique for medical residents in training.

Low-Latitude Ethane Rain on Titan

NASA Technical Reports Server (NTRS)

Dalba, Paul A.; Buratti, Bonnie J.; Brown, R. H.; Barnes, J. W.; Baines, K. H.; Sotin, C.; Clark, R. N.; Lawrence, K. J.; Nicholson, P. D.

2012-01-01

Cassini ISS observed multiple widespread changes in surface brightness in Titan's equatorial regions over the past three years. These brightness variations are attributed to rainfall from cloud systems that appear to form seasonally. Determining the composition of this rainfall is an important step in understanding the "methanological" cycle on Titan. I use data from Cassini VIMS to complete a spectroscopic investigation of multiple rain-wetted areas. I compute "before-and-after" spectral ratios of any areas that show either deposition or evaporation of rain. By comparing these spectral ratios to a model of liquid ethane, I find that the rain is most likely composed of liquid ethane. The spectrum of liquid ethane contains multiple absorption features that fall within the 2-micron and 5-micron spectral windows in Titan's atmosphere. I show that these features are visible in the spectra taken of Titan's surface and that they are characteristically different than those in the spectrum of liquid methane. Furthermore, just as ISS saw the surface brightness reverting to its original state after a period of time, I show that VIMS observations of later flybys show the surface composition in different stages of returning to its initial form.

Multiple and substitute addictions involving prescription drugs misuse among 12th graders: gateway theory revisited with Market Basket Analysis.

PubMed

Jayawardene, Wasantha Parakrama; YoussefAgha, Ahmed Hassan

2014-01-01

This study aimed to identify the sequential patterns of drug use initiation, which included prescription drugs misuse (PDM), among 12th-grade students in Indiana. The study also tested the suitability of the data mining method Market Basket Analysis (MBA) to detect common drug use initiation sequences in large-scale surveys. Data from 2007 to 2009 Annual Surveys of Alcohol, Tobacco, and Other Drug Use by Indiana Children and Adolescents were used for this study. A close-ended, self-administered questionnaire was used to ask adolescents about the use of 21 substance categories and the age of first use. "Support%" and "confidence%" statistics of Market Basket Analysis detected multiple and substitute addictions, respectively. The lifetime prevalence of using any addictive substance was 73.3%, and it has been decreasing during past few years. Although the lifetime prevalence of PDM was 19.2%, it has been increasing. Males and whites were more likely to use drugs and engage in multiple addictions. Market Basket Analysis identified common drug use initiation sequences that involved 11 drugs. High levels of support existed for associations among alcohol, cigarettes, and marijuana, whereas associations that included prescription drugs had medium levels of support. Market Basket Analysis is useful for the detection of common substance use initiation sequences in large-scale surveys. Before initiation of prescription drugs, physicians should consider the adolescents' risk of addiction. Prevention programs should address multiple addictions, substitute addictions, common sequences in drug use initiation, sex and racial differences in PDM, and normative beliefs of parents and adolescents in relation to PDM.

Rate of revisions or conversion after bariatric surgery over 10 years in the state of New York.

PubMed

Altieri, Maria S; Yang, Jie; Nie, Lizhou; Blackstone, Robin; Spaniolas, Konstantinos; Pryor, Aurora

2018-04-01

A primary measure of the success of a procedure is the whether or not additional surgery may be necessary. Multi-institutional studies regarding the need for reoperation after bariatric surgery are scarce. The purpose of this study is to evaluate the rate of revisions/conversions (RC) after 3 common bariatric procedures over 10 years in the state of New York. University Hospital, involving a large database in New York State. The Statewide Planning and Research Cooperative System database was used to identify all patients undergoing laparoscopic adjustable gastric banding (LAGB), sleeve gastrectomy (SG), and Roux-en-Y gastric bypass (RYGB) between 2004 and 2010. Patients were followed for RC to other bariatric procedures for at least 4 years (up to 2014). Multivariable cox proportional hazard regression analysis was performed to identify risk factors for additional surgery after each common bariatric procedure. Multivariable logistic regression was used to check the factors associated with having ≥2 follow-up procedures. There were 40,994 bariatric procedures with 16,444 LAGB, 22,769 RYGB, and 1781 SG. Rate of RC was 26.0% for LAGB, 9.8% for SG, and 4.9% for RYGB. Multiple RC ( = />2) were more common for LAGB (5.7% for LAGB, .5% for RYGB, and .2% for LSG). Band revision/replacements required further procedures compared with patients who underwent conversion to RYGB/SG (939 compared with 48 procedures). Majority of RC were not performed at initial institution (68.2% of LAGB patients, 75.9% for RYGB, 63.7% of SG). Risk factors for multiple procedures included surgery type, as LAGB was more likely to have multiple RC. Reoperation was common for LAGB, but less common for RYGB (4.9%) and SG (9.8%). RC rate are almost twice after SG than after RYGB. LAGB had the highest rate (5.7%) of multiple reoperations. Conversion was the procedure of choice after a failed LAGB. Copyright © 2018 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

A palliative care hotline for multiple sclerosis: A pilot feasibility study.

PubMed

Knies, Andrea K; Golla, Heidrun; Strupp, Julia; Galushko, Maren; Schipper, Sabine; Voltz, Raymond

2015-08-01

Research findings suggest that patients severely affected by multiple sclerosis benefit from palliative care. Our objectives were to (1) implement a pilot palliative care counseling hotline for severely affected multiple sclerosis patients and their caregivers in order to connect them to palliative care, and (2) evaluate its preliminary feasibility through a pilot study. The hotline was designed in cooperation with the local state association of the German Multiple Sclerosis Society and based on a review of the literature. The initial study setting for the hotline was the broader region of the cities Cologne and Bonn in Germany. The hotline was introduced through a magazine published by the German Multiple Sclerosis Society and leaflets sent to local healthcare providers. Calls were conducted using a semistructured interview guide and documented by a standardized case report form. Measures to assess feasibility were both quantitative (e.g., number of calls) and qualitative (e.g., criteria for eligibility for palliative care). During its pilot year, the hotline received 18 calls. Some 15 callers were included in the analysis, and 10 of these 15 were deemed eligible for palliative care due to such criteria as medical characteristics, care or nursing conditions, caregiver strain, and concerns regarding death and dying. Access to palliative care services could be provided for all 10 callers. Based on our pilot feasibility study, the hotline seems to be a valuable service for patients severely affected by multiple sclerosis (MS) and their caregivers in order to gain information about and access to palliative care. It will be extended on a nationwide scale through a grant of the German Multiple Sclerosis Society. Awareness of the hotline needs to be enhanced in order to attract and support a significant number of new callers.

A mathematical analysis of multiple-target SELEX.

PubMed

Seo, Yeon-Jung; Chen, Shiliang; Nilsen-Hamilton, Marit; Levine, Howard A

2010-10-01

SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is a procedure by which a mixture of nucleic acids can be fractionated with the goal of identifying those with specific biochemical activities. One combines the mixture with a specific target molecule and then separates the target-NA complex from the resulting reactions. The target-NA complex is separated from the unbound NA by mechanical means (such as by filtration), the NA is eluted from the complex, amplified by PCR (polymerase chain reaction), and the process repeated. After several rounds, one should be left with the nucleic acids that best bind to the target. The problem was first formulated mathematically in Irvine et al. (J. Mol. Biol. 222:739-761, 1991). In Levine and Nilsen-Hamilton (Comput. Biol. Chem. 31:11-25, 2007), a mathematical analysis of the process was given. In Vant-Hull et al. (J. Mol. Biol. 278:579-597, 1998), multiple target SELEX was considered. It was assumed that each target has a single nucleic acid binding site that permits occupation by no more than one nucleic acid. Here, we revisit Vant-Hull et al. (J. Mol. Biol. 278:579-597, 1998) using the same assumptions. The iteration scheme is shown to be convergent and a simplified algorithm is given. Our interest here is in the behavior of the multiple target SELEX process as a discrete "time" dynamical system. Our goal is to characterize the limiting states and their dependence on the initial distribution of nucleic acid and target fraction components. (In multiple target SELEX, we vary the target component fractions, but not their concentrations, as fixed and the initial pool of nucleic acids as a variable starting condition). Given N nucleic acids and a target consisting of M subtarget component species, there is an M × N matrix of affinities, the (i,j) entry corresponding to the affinity of the jth nucleic acid for the ith subtarget. We give a structure condition on this matrix that is equivalent to the following statement: For any initial pool of nucleic acids such that all N species are represented, the dynamical system defined by the multiple target SELEX process will converge to a unique subset of nucleic acids, each of whose concentrations depend only upon the total nucleic acid concentration, the initial fractional target distribution (both of which are assumed to be the same from round to round), and the overall limiting association constant. (The overall association constant is the equilibrium constant for the system of MN reactions when viewed as a composite single reaction). This condition is equivalent to the statement that every member of a certain family of chemical potentials at infinite target dilution can have at most one critical point. (The condition replaces the statement for single target SELEX that the dynamical system generated via the process always converges to a pool that contains only the nucleic acid that binds best to the target). This suggests that the effectiveness of multiple target SELEX as a separation procedure may not be as useful as single target SELEX unless the thermodynamic properties of these chemical potentials are well understood.

Eccentricity Evolution of Extrasolar Multiple Planetary Systems Due to the Depletion of Nascent Protostellar Disks

NASA Astrophysics Data System (ADS)

Nagasawa, M.; Lin, D. N. C.; Ida, S.

2003-04-01

Most extrasolar planets are observed to have eccentricities much larger than those in the solar system. Some of these planets have sibling planets, with comparable masses, orbiting around the same host stars. In these multiple planetary systems, eccentricity is modulated by the planets' mutual secular interaction as a consequence of angular momentum exchange between them. For mature planets, the eigenfrequencies of this modulation are determined by their mass and semimajor axis ratios. However, prior to the disk depletion, self-gravity of the planets' nascent disks dominates the precession eigenfrequencies. We examine here the initial evolution of young planets' eccentricity due to the apsidal libration or circulation induced by both the secular interaction between them and the self-gravity of their nascent disks. We show that as the latter effect declines adiabatically with disk depletion, the modulation amplitude of the planets' relative phase of periapsis is approximately invariant despite the time-asymmetrical exchange of angular momentum between planets. However, as the young planets' orbits pass through a state of secular resonance, their mean eccentricities undergo systematic quantitative changes. For applications, we analyze the eccentricity evolution of planets around υ Andromedae and HD 168443 during the epoch of protostellar disk depletion. We find that the disk depletion can change the planets' eccentricity ratio. However, the relatively large amplitude of the planets' eccentricity cannot be excited if all the planets had small initial eccentricities.

Mechanism for multiplicity of steady states with distinct cell concentration in continuous culture of mammalian cells.

PubMed

Yongky, Andrew; Lee, Jongchan; Le, Tung; Mulukutla, Bhanu Chandra; Daoutidis, Prodromos; Hu, Wei-Shou

2015-07-01

Continuous culture for the production of biopharmaceutical proteins offers the possibility of steady state operations and thus more consistent product quality and increased productivity. Under some conditions, multiplicity of steady states has been observed in continuous cultures of mammalian cells, wherein with the same dilution rate and feed nutrient composition, steady states with very different cell and product concentrations may be reached. At those different steady states, cells may exhibit a high glycolysis flux with high lactate production and low cell concentration, or a low glycolysis flux with low lactate and high cell concentration. These different steady states, with different cell concentration, also have different productivity. Developing a mechanistic understanding of the occurrence of steady state multiplicity and devising a strategy to steer the culture toward the desired steady state is critical. We establish a multi-scale kinetic model that integrates a mechanistic intracellular metabolic model and cell growth model in a continuous bioreactor. We show that steady state multiplicity exists in a range of dilution rate in continuous culture as a result of the bistable behavior in glycolysis. The insights from the model were used to devise strategies to guide the culture to the desired steady state in the multiple steady state region. The model provides a guideline principle in the design of continuous culture processes of mammalian cells. © 2015 Wiley Periodicals, Inc.

Coalescence-Induced Jumping of Multiple Condensate Droplets on Hierarchical Superhydrophobic Surfaces

PubMed Central

Chen, Xuemei; Patel, Ravi S.; Weibel, Justin A.; Garimella, Suresh V.

2016-01-01

Coalescence-induced jumping of condensate droplets from a superhydrophobic surface with hierarchical micro/nanoscale roughness is quantitatively characterized. Experimental observations show that the condensate droplet jumping is induced by coalescence of multiple droplets of different sizes, and that the coalesced droplet trajectories typically deviate from the surface normal. A depth-from-defocus image processing technique is developed to track the out-of-plane displacement of the jumping droplets, so as to accurately measure the droplet size and velocity. The results demonstrate that the highest jumping velocity is achieved when two droplets coalesce. The jumping velocity decreases gradually with an increase in the number of coalescing droplets, despite the greater potential surface energy released upon coalescence. A general theoretical model that accounts for viscous dissipation, surface adhesion, line tension, the initial droplet wetting states, and the number and sizes of the coalescing droplets is developed to explain the trends of droplet jumping velocity observed in the experiments. PMID:26725512

A Sequential Multiplicative Extended Kalman Filter for Attitude Estimation Using Vector Observations.

PubMed

Qin, Fangjun; Chang, Lubin; Jiang, Sai; Zha, Feng

2018-05-03

In this paper, a sequential multiplicative extended Kalman filter (SMEKF) is proposed for attitude estimation using vector observations. In the proposed SMEKF, each of the vector observations is processed sequentially to update the attitude, which can make the measurement model linearization more accurate for the next vector observation. This is the main difference to Murrell’s variation of the MEKF, which does not update the attitude estimate during the sequential procedure. Meanwhile, the covariance is updated after all the vector observations have been processed, which is used to account for the special characteristics of the reset operation necessary for the attitude update. This is the main difference to the traditional sequential EKF, which updates the state covariance at each step of the sequential procedure. The numerical simulation study demonstrates that the proposed SMEKF has more consistent and accurate performance in a wide range of initial estimate errors compared to the MEKF and its traditional sequential forms.

A Sequential Multiplicative Extended Kalman Filter for Attitude Estimation Using Vector Observations

PubMed Central

Qin, Fangjun; Jiang, Sai; Zha, Feng

2018-01-01

In this paper, a sequential multiplicative extended Kalman filter (SMEKF) is proposed for attitude estimation using vector observations. In the proposed SMEKF, each of the vector observations is processed sequentially to update the attitude, which can make the measurement model linearization more accurate for the next vector observation. This is the main difference to Murrell’s variation of the MEKF, which does not update the attitude estimate during the sequential procedure. Meanwhile, the covariance is updated after all the vector observations have been processed, which is used to account for the special characteristics of the reset operation necessary for the attitude update. This is the main difference to the traditional sequential EKF, which updates the state covariance at each step of the sequential procedure. The numerical simulation study demonstrates that the proposed SMEKF has more consistent and accurate performance in a wide range of initial estimate errors compared to the MEKF and its traditional sequential forms. PMID:29751538

Towards a comparable carbon footprint for local initiatives: The FP7 project TESS

NASA Astrophysics Data System (ADS)

Reusser, Dominik E.; Kropp, Jürgen P.

2014-05-01

TESS (Towards European Societal Sustainability -- www.tess-transition.eu) is a three-year, European-wide research project. It aims to reach an understanding of the potential for community-led initiatives to help deliver a truly sustainable, low-carbon future. Transitions to low-carbon societies take place at multiple and complementary scales. Transition processes are highly dependent on the innovative potential of community-based initiatives and their articulation with appropriate institutional architecture. Community-based initiatives are potentially more adaptable and less constrained by current structural circumstances than top-down policies and can give impetus to large-scale and technology driven changes. TESS will provide an understanding on the upscaling possibilities of such high-potential community-based initiatives by addressing two main questions: What is the impact of community-based initiatives in terms of carbon reduction potential and economic effect? What institutional structures (values, policies and mechanisms) support these initiatives in persisting beyond the initial phase and moving into an acceleration phase, spreading desired impacts? Answers will be provided through (1) a novel measuring, reporting and verification (MRV) framework for benchmarking community-based initiatives. This will enable quantifiable, comparable and standardised evaluation, and (2) the identification of success factors for the emergence, persistence and diffusion of promising initiatives, including online initiatives. We will identify these initiatives through case studies across regions and sectors and produce a systemic understanding of their impact on societal transitions towards sustainability. Our research will be integrated and transdisciplinary, with the unique opportunity to bring together social and natural scientists to foster a transition towards European societal sustainability. Our work will feed into and extend the Climate Adapt database to facilitate reconciliation of mitigation and adaptation and connect to Europe wide evaluation approaches such as the Common Monitoring and Evaluation Framework (CMEF) of the Rural Development Programmes. The poster will show the current state of the initiative selection process and of the method development.

Correlates of HPV vaccine initiation and provider recommendation among male adolescents, 2014 NIS-Teen.

PubMed

Landis, Kathryn; Bednarczyk, Robert A; Gaydos, Laura M

2018-05-08

Vaccination is a safe and effective way to prevent Human Papillomavirus (HPV) infection and related cancers; however, HPV vaccine uptake remains low in the US. After the 2011 Advisory Committee on Immunization Practices (ACIP) recommendation for routine HPV vaccination of adolescent males, several studies have examined predictors for initiating the vaccine series in this population of interest, particularly with regard to provider recommendations. This study examined racial and ethnic differences for HPV vaccine initiation and provider recommendation in male adolescents. Based on prior HPV vaccine uptake estimates and healthcare utilization data, we hypothesized that minority adolescents would be more likely to initiate HPV vaccines, but less likely to receive a provider recommendation compared to white counterparts. We analyzed the 2014 National Immunization Survey-Teen (NIS-Teen), which included 10,753 male adolescents with provider-verified vaccination data in 50 US states, using multivariate logistic regression models to evaluate racial/ethnic differences in HPV vaccine initiation and provider recommendation. The odds of HPV vaccine initiation were 76 percent higher for Hispanic adolescents and 43 percent higher for non-Hispanic Other or Multiple race adolescents compared to white adolescents. Approximately half of parents reported receiving a provider recommendation for vaccination, with no significant difference in the odds of receiving a provider recommendation across racial/ethnic groups. Despite similar frequency of recommendations across racial and ethnic groups, male adolescents who are racial/ethnic minorities are more likely to initiate vaccination. Future research should focus on developing tailored interventions to increase HPV vaccine receipt among males of all racial/ethnic groups. Copyright © 2018 Elsevier Ltd. All rights reserved.

Deactivation via ring opening: A quantum chemical study of the excited states of furan and comparison to thiophene

NASA Astrophysics Data System (ADS)

Gavrilov, Nemanja; Salzmann, Susanne; Marian, Christel M.

2008-06-01

Minimum nuclear arrangements of the ground and low-lying excited electronic states of furan were obtained by means of (time dependent) Kohn-Sham density functional theory. A combined density functional/multi-reference configuration interaction method (DFT/MRCI) was employed to compute the spectral properties at these points. Multiple minima were found on the first excited singlet (S 1) potential energy hypersurface with electronic structures S1, S2, S3 corresponding to the 1 1A 2 (π → 3s-Ryd), 1 1B 2 (π → π ∗), and 2 1A 1 (π → π ∗) states in the vertical absorption spectrum, respectively. In analogy to recently published studies in thiophene [S. Salzmann, M. Kleinschmidt, J. Tatchen, R. Weinkauf, C.M. Marian, Phys. Chem. Chem. Phys. 10 (2008) 380] a deactivation mechanism for electronically excited furan was detected that involves the opening of the pentacyclic ring. We found a nearly barrierless relaxation pathway from the Franck-Condon region along a C-O bond-breaking coordinate. Hereby the initially excited 1B 2 (π → π ∗) state undergoes a conical intersection with a 1B 1 (π → σ ∗) state. The system can return to the electronic ground state through a second conical intersection of the 1(π → σ ∗) state before the minimum of that B 1 state is reached.

Thin Shell evolution of NIF capsule with asymmetric drive and the resulting neutron diagnostics

NASA Astrophysics Data System (ADS)

Buchoff, Michael; Hammer, Jim

2015-11-01

One of the major impediments to achieving ignition via ICF is the non-spherical implosion arising from small asymmetries in the drive forcing the collapse of the capsule. Likewise, an experimental diagnostic for quantifying the characteristics of the implosion asymmetry is the final state neutrons, whose number and velocity distributions are not experimentally consistent with the expectation of a spherical implosion. In principle, connecting these initial and final state asymmetries could be solved via hydrodynamic simulations, but due to the multiple scales traversed throughout this process, these calculations are difficult and expensive, leaving much of the potential drive asymmetry profiles unexplored. In this work, we solve the resulting analytic equations from the thin-shell model proposed by Ott et. al. to evolve the capsule over a range of different drive asymmetries from its initial state (when the shell aspect ratio is much greater than 1) to a radius of roughly 250 microns, consisting of a layer of dense CH, a cold layer of dense DT, and a warm core of sparsely distributed DT. At this stage, more tractable hydrodynamical simulations are performed in the ARES code suite, determining the distribution of neutron from thermonuclear yield. These and future results allow for a multitude of tests of asymmetric sources to compare with and potentially guide experiment. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Part-to-itself model inversion in process compensated resonance testing

NASA Astrophysics Data System (ADS)

Mayes, Alexander; Jauriqui, Leanne; Biedermann, Eric; Heffernan, Julieanne; Livings, Richard; Aldrin, John C.; Goodlet, Brent; Mazdiyasni, Siamack

2018-04-01

Process Compensated Resonance Testing (PCRT) is a non-destructive evaluation (NDE) method involving the collection and analysis of a part's resonance spectrum to characterize its material or damage state. Prior work used the finite element method (FEM) to develop forward modeling and model inversion techniques. In many cases, the inversion problem can become confounded by multiple parameters having similar effects on a part's resonance frequencies. To reduce the influence of confounding parameters and isolate the change in a part (e.g., creep), a part-to-itself (PTI) approach can be taken. A PTI approach involves inverting only the change in resonance frequencies from the before and after states of a part. This approach reduces the possible inversion parameters to only those that change in response to in-service loads and damage mechanisms. To evaluate the effectiveness of using a PTI inversion approach, creep strain and material properties were estimated in virtual and real samples using FEM inversion. Virtual and real dog bone samples composed of nickel-based superalloy Mar-M-247 were examined. Virtual samples were modeled with typically observed variations in material properties and dimensions. Creep modeling was verified with the collected resonance spectra from an incrementally crept physical sample. All samples were inverted against a model space that allowed for change in the creep damage state and the material properties but was blind to initial part dimensions. Results quantified the capabilities of PTI inversion in evaluating creep strain and material properties, as well as its sensitivity to confounding initial dimensions.

Lack of multiplicative transitivity in person trade-off responses.

PubMed

Schwarzinger, Michaël; Lanoë, Jean-Louis; Nord, Erik; Durand-Zaleski, Isabelle

2004-02-01

The person trade-off (PTO) is a technique for eliciting preferences for resource allocation across patient groups. In principle PTO responses should satisfy a requirement of multiplicative transitivity, i.e. that if people consider treatment of 1 in state A to be equivalent to treating 10 in state B, and 1 in state B to be equivalent to 10 in state C, then they should find 1 in state A equivalent to 100 in state C. Earlier studies addressing labelled diseases (specific diagnoses), have shown multiplicative intransitivity of the PTO responses. Our purpose was to test multiplicative transitivity in the case of health states described with the EuroQol instrument only and to find a possible framing effect such as the number of persons in the reference intervention. Forty-four master degree students were asked to fill in a questionnaire addressing four chronic health states. Their task consisted in (1). ranking the states by severity, (2). valuing each of them by the means of the time trade-off, and (3). doing the PTO for all the 10 possible pairwise combinations of the four chronic states plus a fatal one. In a subsequent questionnaire the number of persons in the reference intervention in the PTO was increased from 10 to 100. Multiplicative transitivity was studied in subjects who demonstrated a willingness to trade off and consistency in ranking individual values. None of the 39 subjects included satisfied a minimum multiplicative transitivity requirement in PTO responses. Internal consistency was not improved when the PTO involved health states close to each other in terms of severity, nor when the prevention of death was not the reference intervention. For the 22 subjects having answered both types of questionnaire, increasing the number of persons in the reference intervention did not improve multiplicative transitivity. The PTO holds promise as a useful method for determining social preferences for priority setting, inasmuch as it captures distributive concerns that individual utility techniques such as the time trade-off do not address. But the lack of multiplicative transitivity in PTO responses is unsatisfactory, and ways to reduce this problem need to be explored. Copyright 2003 John Wiley & Sons, Ltd.

Management Strategies to Facilitate Optimal Outcomes for Patients Treated with Delayed-release Dimethyl Fumarate.

PubMed

Mayer, Lori; Fink, Mary Kay; Sammarco, Carrie; Laing, Lisa

2018-04-01

Delayed-release dimethyl fumarate is an oral disease-modifying therapy that has demonstrated significant efficacy in adults with relapsing-remitting multiple sclerosis. Incidences of flushing and gastrointestinal adverse events are common in the first month after delayed-release dimethyl fumarate initiation. Our objective was to propose mitigation strategies for adverse events related to initiation of delayed-release dimethyl fumarate in the treatment of patients with multiple sclerosis. Studies of individually developed mitigation strategies and chart reviews were evaluated. Those results, as well as mitigation protocols developed at multiple sclerosis care centers, are summarized. Key steps to optimize the effectiveness of delayed-release dimethyl fumarate treatment include education prior to and at the time of delayed-release dimethyl fumarate initiation, initiation dose protocol gradually increasing to maintenance dose, dietary suggestions for co-administration with food, gastrointestinal symptom management with over-the-counter medications, flushing symptom management with aspirin, and temporary dose reduction. Using the available evidence from clinical trials and evaluations of post-marketing studies, these strategies to manage gastrointestinal and flushing symptoms can be effective and helpful to the patient when initiating delayed-release dimethyl fumarate.

Numerical simulations of the process of multiple shock-flame interactions

NASA Astrophysics Data System (ADS)

Jiang, Hua; Dong, Gang; chen, Xiao; Wu, Jin-Tao

2016-08-01

Based on a weighted essentially nonoscillatory scheme, the multiple interactions of a flame interface with an incident shock wave and its reshock waves are numerically simulated by solving the compressible reactive Navier-Stokes equations with a single-step Arrhenius chemical reaction. The two-dimensional sinusoidally perturbed premixed flames with different initial perturbed amplitudes are used to investigate the effect of the initial perturbation on the flame evolutions. The results show that the development of the flame interface is directly affected by the initial perturbed amplitudes before the passages of reshock waves, and the perturbation development is mainly controlled by the Richtmyer-Meshkov instability (RMI). After the successive impacts of multiple reshock waves, the chemical reaction accelerates the consumption of reactants and leads to a gradual disappearance of the initial perturbed information. The perturbation developments in frozen flows with the same initial interface as those in reactive flows are also demonstrated. Comparisons of results between the reactive and frozen flows show that a chemical reaction changes the perturbation pattern of the flame interface by decreasing the density gradient, thereby weakening the baroclinic torque in the flame mixing region, and therefore plays a dominant role after the passage of reshock waves.

A Cognitive System Model for Human/Automation Dynamics in Airspace Management

NASA Technical Reports Server (NTRS)

Corker, Kevin M.; Pisanich, Gregory; Lebacqz, J. Victor (Technical Monitor)

1997-01-01

NASA has initiated a significant thrust of research and development focused on providing the flight crew and air traffic managers automation aids to increase capacity in en route and terminal area operations through the use of flexible, more fuel-efficient routing, while improving the level of safety in commercial carrier operations. In that system development, definition of cognitive requirements for integrated multi-operator dynamic aiding systems is fundamental. In order to support that cognitive function definition, we have extended the Man Machine Integrated Design and Analysis System (MIDAS) to include representation of multiple cognitive agents (both human operators and intelligent aiding systems) operating aircraft, airline operations centers and air traffic control centers in the evolving airspace. The demands of this application require representation of many intelligent agents sharing world-models, and coordinating action/intention with cooperative scheduling of goals and actions in a potentially unpredictable world of operations. The MIDAS operator models have undergone significant development in order to understand the requirements for operator aiding and the impact of that aiding in the complex nondeterminate system of national airspace operations. The operator model's structure has been modified to include attention functions, action priority, and situation assessment. The cognitive function model has been expanded to include working memory operations including retrieval from long-term store, interference, visual-motor and verbal articulatory loop functions, and time-based losses. The operator's activity structures have been developed to include prioritization and interruption of multiple parallel activities among multiple operators, to provide for anticipation (knowledge of the intention and action of remote operators), and to respond to failures of the system and other operators in the system in situation-specific paradigms. The model's internal representation has been be modified so that multiple, autonomous sets of equipment will function in a scenario as the single equipment sets do now. In order to support the analysis requirements with multiple items of equipment, it is necessary for equipment to access the state of other equipment objects at initialization time (a radar object may need to access the position and speed of aircraft in its area, for example), and as a function of perception and sensor system interaction. The model has been improved to include multiple world-states as a function of equipment am operator interaction. The model has been used -1o predict the impact of warning and alert zones in aircraft operation, and, more critic-ally, the interaction of flight-deck based warning mechanisms and air traffic controller action in response to ground-based conflict prediction and alerting systems. In this operation, two operating systems provide alerting to two autonomous, but linked sets of operators, whose view of the system and whose dynamics in response are radically different. System stability and operator action was predicted using the MIDAS model.

Responding to climate change and the global land crisis: REDD+, market transformation and low-emissions rural development

PubMed Central

Nepstad, Daniel C.; Boyd, William; Stickler, Claudia M.; Bezerra, Tathiana; Azevedo, Andrea A.

2013-01-01

Climate change and rapidly escalating global demand for food, fuel, fibre and feed present seemingly contradictory challenges to humanity. Can greenhouse gas (GHG) emissions from land-use, more than one-fourth of the global total, decline as growth in land-based production accelerates? This review examines the status of two major international initiatives that are designed to address different aspects of this challenge. REDD+ is an emerging policy framework for providing incentives to tropical nations and states that reduce their GHG emissions from deforestation and forest degradation. Market transformation, best represented by agricultural commodity roundtables, seeks to exclude unsustainable farmers from commodity markets through international social and environmental standards for farmers and processors. These global initiatives could potentially become synergistically integrated through (i) a shared approach for measuring and favouring high environmental and social performance of land use across entire jurisdictions and (ii) stronger links with the domestic policies, finance and laws in the jurisdictions where agricultural expansion is moving into forests. To achieve scale, the principles of REDD+ and sustainable farming systems must be embedded in domestic low-emission rural development models capable of garnering support across multiple constituencies. We illustrate this potential with the case of Mato Grosso State in the Brazilian Amazon. PMID:23610173

Manual for the Jet Event and Background Simulation Library(JEBSimLib)

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

Heinz, Matthias; Soltz, Ron; Angerami, Aaron

Jets are the collimated streams of particles resulting from hard scattering in the initial state of high-energy collisions. In heavy-ion collisions, jets interact with the quark-gluon plasma (QGP) before freezeout, providing a probe into the internal structure and properties of the QGP. In order to study jets, background must be subtracted from the measured event, potentially introducing a bias. We aim to understand and quantify this subtraction bias. PYTHIA, a library to simulate pure jet events, is used to simulate a model for a signature with one pure jet (a photon) and one quenched jet, where all quenched particle momentamore » are reduced by a user-de ned constant fraction. Background for the event is simulated using multiplicity values generated by the TRENTO initial state model of heavy-ion collisions fed into a thermal model consisting of a 3-dimensional Boltzmann distribution for particle types and momenta. Data from the simulated events is used to train a statistical model, which computes a posterior distribution of the quench factor for a data set. The model was tested rst on pure jet events and then on full events including the background. This model will allow for a quantitative determination of biases induced by various methods of background subtraction.« less

Manual for the Jet Event and Background Simulation Library

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

Heinz, M.; Soltz, R.; Angerami, A.

Jets are the collimated streams of particles resulting from hard scattering in the initial state of high-energy collisions. In heavy-ion collisions, jets interact with the quark-gluon plasma (QGP) before freezeout, providing a probe into the internal structure and properties of the QGP. In order to study jets, background must be subtracted from the measured event, potentially introducing a bias. We aim to understand and quantify this subtraction bias. PYTHIA, a library to simulate pure jet events, is used to simulate a model for a signature with one pure jet (a photon) and one quenched jet, where all quenched particle momentamore » are reduced by a user-de ned constant fraction. Background for the event is simulated using multiplicity values generated by the TRENTO initial state model of heavy-ion collisions fed into a thermal model consisting of a 3-dimensional Boltzmann distribution for particle types and momenta. Data from the simulated events is used to train a statistical model, which computes a posterior distribution of the quench factor for a data set. The model was tested rst on pure jet events and then on full events including the background. This model will allow for a quantitative determination of biases induced by various methods of background subtraction.« less

Responding to climate change and the global land crisis: REDD+, market transformation and low-emissions rural development.

PubMed

Nepstad, Daniel C; Boyd, William; Stickler, Claudia M; Bezerra, Tathiana; Azevedo, Andrea A

2013-06-05

Climate change and rapidly escalating global demand for food, fuel, fibre and feed present seemingly contradictory challenges to humanity. Can greenhouse gas (GHG) emissions from land-use, more than one-fourth of the global total, decline as growth in land-based production accelerates? This review examines the status of two major international initiatives that are designed to address different aspects of this challenge. REDD+ is an emerging policy framework for providing incentives to tropical nations and states that reduce their GHG emissions from deforestation and forest degradation. Market transformation, best represented by agricultural commodity roundtables, seeks to exclude unsustainable farmers from commodity markets through international social and environmental standards for farmers and processors. These global initiatives could potentially become synergistically integrated through (i) a shared approach for measuring and favouring high environmental and social performance of land use across entire jurisdictions and (ii) stronger links with the domestic policies, finance and laws in the jurisdictions where agricultural expansion is moving into forests. To achieve scale, the principles of REDD+ and sustainable farming systems must be embedded in domestic low-emission rural development models capable of garnering support across multiple constituencies. We illustrate this potential with the case of Mato Grosso State in the Brazilian Amazon.

e-Science Partnerships: Towards a Sustainable Framework for School-Scientist Engagement

NASA Astrophysics Data System (ADS)

Falloon, Garry

2013-08-01

In late 2006, the New Zealand Government embarked on a series of initiatives to explore how the resources and expertise of eight, small, state-owned science research institutes could be combined efficiently to support science teaching in schools. Programmes were developed to enable students and teachers to access and become involved in local science research and innovation, with the aim being to broaden their awareness of New Zealand science research contexts, adding authenticity and relevance to their school studies. One of these initiatives, known as Science-for-Life, partnered scientists with teachers and students in primary and secondary schools (K-12). A key output from the trial phase of Science-for-Life was the generation of a framework for guiding and coordinating the activities of the eight institutes within the education sector, to improve efficiency, effectiveness and promote sustainability. The framework, based on data gathered from a series of interviews with each institute's Chief Executive Officer (CEO), an online questionnaire, and informed by findings from trial partnership case studies published as institute technical reports and published articles, is presented in this paper. While the framework is developed from New Zealand data, it is suggested that it may be useful for coordinating interactions between multiple small science organisations and the school sector in other small-nation or state contexts.

Bladder Preservation for Localized Muscle-Invasive Bladder Cancer: The Survival Impact of Local Utilization Rates of Definitive Radiotherapy

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

Kozak, Kevin R.; Hamidi, Maryam; Manning, Matthew

2012-06-01

Purpose: This study examines the management and outcomes of muscle-invasive bladder cancer in the United States. Methods and Materials: Patients with muscle-invasive bladder cancer diagnosed between 1988 and 2006 were identified in the Surveillance, Epidemiology, and End Results (SEER) database. Patients were classified according to three mutually exclusive treatment categories based on the primary initial treatment: no local management, radiotherapy, or surgery. Overall survival was assessed with Kaplan-Meier analysis and Cox models based on multiple factors including treatment utilization patterns. Results: The study population consisted of 26,851 patients. Age, sex, race, tumor grade, histology, and geographic location were associated withmore » differences in treatment (all p < 0.01). Patients receiving definitive radiotherapy tended to be older and have less differentiated tumors than patients undergoing surgery (RT, median age 78 years old and 90.6% grade 3/4 tumors; surgery, median age 71 years old and 77.1% grade 3/4 tumors). No large shifts in treatment were seen over time, with most patients managed with surgical resection (86.3% for overall study population). Significant survival differences were observed according to initial treatment: median survival, 14 months with no definitive local treatment; 17 months with radiotherapy; and 43 months for surgery. On multivariate analysis, differences in local utilization rates of definitive radiotherapy did not demonstrate a significant effect on overall survival (hazard ratio, 1.002; 95% confidence interval, 0.999-1.005). Conclusions: Multiple factors influence the initial treatment strategy for muscle-invasive bladder cancer, but definitive radiotherapy continues to be used infrequently. Although patients who undergo surgery fare better, a multivariable model that accounted for patient and tumor characteristics found no survival detriment to the utilization of definitive radiotherapy. These results support continued research into bladder preservation strategies and suggest that definitive radiotherapy represents a viable initial treatment strategy for those who wish to attempt to preserve their native bladder.« less

HURON (HUman and Robotic Optimization Network) Multi-Agent Temporal Activity Planner/Scheduler

NASA Technical Reports Server (NTRS)

Hua, Hook; Mrozinski, Joseph J.; Elfes, Alberto; Adumitroaie, Virgil; Shelton, Kacie E.; Smith, Jeffrey H.; Lincoln, William P.; Weisbin, Charles R.

2012-01-01

HURON solves the problem of how to optimize a plan and schedule for assigning multiple agents to a temporal sequence of actions (e.g., science tasks). Developed as a generic planning and scheduling tool, HURON has been used to optimize space mission surface operations. The tool has also been used to analyze lunar architectures for a variety of surface operational scenarios in order to maximize return on investment and productivity. These scenarios include numerous science activities performed by a diverse set of agents: humans, teleoperated rovers, and autonomous rovers. Once given a set of agents, activities, resources, resource constraints, temporal constraints, and de pendencies, HURON computes an optimal schedule that meets a specified goal (e.g., maximum productivity or minimum time), subject to the constraints. HURON performs planning and scheduling optimization as a graph search in state-space with forward progression. Each node in the graph contains a state instance. Starting with the initial node, a graph is automatically constructed with new successive nodes of each new state to explore. The optimization uses a set of pre-conditions and post-conditions to create the children states. The Python language was adopted to not only enable more agile development, but to also allow the domain experts to easily define their optimization models. A graphical user interface was also developed to facilitate real-time search information feedback and interaction by the operator in the search optimization process. The HURON package has many potential uses in the fields of Operations Research and Management Science where this technology applies to many commercial domains requiring optimization to reduce costs. For example, optimizing a fleet of transportation truck routes, aircraft flight scheduling, and other route-planning scenarios involving multiple agent task optimization would all benefit by using HURON.

Self-Management for People with Multiple Sclerosis

PubMed Central

Fraser, Robert; Ehde, Dawn; Amtmann, Dagmar; Johnson, Kurt L.; Johnson, Erica; Kraft, George H.

2013-01-01

People with multiple sclerosis (MS) must manage the day-to-day effects of the disease on their lives. Self-management interventions may be helpful in this challenge. An international, multidisciplinary consensus conference was held on November 15, 2010, by the University of Washington's Rehabilitation Research and Training Center for Multiple Sclerosis (MS RRTC), with funding from the Consortium of Multiple Sclerosis Centers (CMSC) and the National Institute on Disability and Rehabilitation Research (NIDRR), to discuss the concept of self-management for people with MS. The specific goals of the consensus conference were as follows: 1) review the current research on self-management and related issues in chronic disability and specifically in MS; 2) review optimal research methodologies, outcome measurement tools, program planning frameworks, and dissemination strategies for self-management research; and 3) establish recommendations on the next steps necessary to develop, adapt, and test self-management interventions for people with MS. The consensus conference and this document are the initial steps toward achieving the stated goals. Participants in the consensus conference concluded that it is necessary to: 1) define an empirically based conceptual model of self-management for people with MS; 2) establish reliable and valid self-management outcome measures; 3) use best practices to validate models of self-management interventions; and 4) plan dissemination and knowledge translation of interventions once their effectiveness is established. PMID:24453769

Pharmacokinetic profile of extended-release versus immediate-release oral naproxen sodium after single and multiple dosing under fed and fasting conditions: two randomized, open-label trials.

PubMed

Laurora, Irene; Wang, Yuan

2016-10-01

Extended-release (ER) naproxen sodium provides pain relief for up to 24 hours with a single dose (660 mg/day). Its pharmacokinetic profile after single and multiple dosing was compared to immediate release (IR) naproxen sodium in two randomized, open-label, crossover studies, under fasting and fed conditions. Eligible healthy subjects were randomized to ER naproxen sodium 660-mg tablet once daily or IR naproxen sodium 220-mg tablet twice daily (440 mg initially, followed by 220 mg 12 hours later). Primary variables: pharmacokinetic parameters after singleday administration (day 1) and at steady state after multiple-day administration (day 6). Total exposure was comparable for both treatments under fasting and fed conditions. After fasting: peak naproxen concentrations were slightly lower with ER naproxen sodium than with IR naproxen sodium but were reached at a similar time. Fed conditions: mean peak concentrations were comparable but reached after a longer time with ER vs. IR naproxen sodium. ER naproxen sodium was well tolerated, with a similar safety profile to IR naproxen sodium. The total exposure of ER naproxen sodium (660 mg) is comparable to IR naproxen sodium (220 mg) when administered at the maximum over the counter (OTC) dose of 660-mg daily dose on a single day and over multiple days. The rate of absorption is delayed under fed conditions.

Outcomes of Multiple Listing for Adult Heart Transplantation in the United States: Analysis of OPTN Data From 2000 to 2013.

PubMed

Givens, Raymond C; Dardas, Todd; Clerkin, Kevin J; Restaino, Susan; Schulze, P Christian; Mancini, Donna M

2015-12-01

This study sought to assess the association of multiple listing with waitlist outcomes and post-heart transplant (HT) survival. HT candidates in the United States may register at multiple centers. Not all candidates have the resources and mobility needed for multiple listing; thus this policy may advantage wealthier and less sick patients. We identified 33,928 adult candidates for a first single-organ HT between January 1, 2000 and December 31, 2013 in the Organ Procurement and Transplantation Network database. We identified 679 multiple-listed (ML) candidates (2.0%) who were younger (median age, 53 years [interquartile range (IQR): 43 to 60 years] vs. 55 years [IQR: 45 to 61 years]; p < 0.0001), more often white (76.4% vs. 70.7%; p = 0.0010) and privately insured (65.5% vs. 56.3%; p < 0.0001), and lived in zip codes with higher median incomes (US$90,153 [IQR: US$25,471 to US$253,831] vs. US$68,986 [IQR: US$19,471 to US$219,702]; p = 0.0015). Likelihood of ML increased with the primary center's median waiting time. ML candidates had lower initial priority (39.0% 1A or 1B vs. 55.1%; p < 0.0001) and predicted 90-day waitlist mortality (2.9% [IQR: 2.3% to 4.7%] vs. 3.6% [IQR: 2.3% to 6.0]%; p < 0.0001), but were frequently upgraded at secondary centers (58.2% 1A/1B; p < 0.0001 vs. ML primary listing). ML candidates had a higher HT rate (74.4% vs. 70.2%; p = 0.0196) and lower waitlist mortality (8.1% vs. 12.2%; p = 0.0011). Compared with a propensity-matched cohort, the relative ML HT rate was 3.02 (95% confidence interval: 2.59 to 3.52; p < 0.0001). There were no post-HT survival differences. Multiple listing is a rational response to organ shortage but may advantage patients with the means to participate rather than the most medically needy. The multiple-listing policy should be overturned. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Use of autologous hematopoietic cell transplantation as initial therapy in multiple myeloma and the impact of socio-geo-demographic factors in the era of novel agents.

PubMed

Al-Hamadani, Mohammed; Hashmi, Shahrukh K; Go, Ronald S

2014-08-01

Very effective combination chemotherapy using novel agents has become available in multiple myeloma (MM). Its impact on the use of high-dose chemotherapy and autologous hematopoietic stem cell transplantation (AHCT) as part of initial therapy is unknown. Using the National Cancer Data Base, we studied the rate of upfront AHCT use among 137,409 newly diagnosed MM patients from 1998 to 2010 in the United States and determined whether disparity exists among various sociodemographic as well as geographic subgroups. Overall, 12,378 (9.0%) patients received AHCT as part of initial treatment. The use of upfront AHCT increased steadily from 5.2% in 1998 to 12.1% in 2010 (trend test, P < 0.001), with no sign of plateau. This was seen across all socio-geo-demographic subgroups except among patients treated in the Northeast where the rate fell from 8.7% in 1998 to 6.6% in 2010. In multivariable analysis, patients with the following characteristics were the least likely to receive AHCT (odds ratio): year of diagnosis from 1998 to 2003 before the era of novel agents (0.67), older age (0.35), Black race (0.58), Hispanic ethnicity (0.78), low level of education or annual household income (0.55), residence in a metro area (0.66), no or unknown medical insurance (0.30), treatment at a community cancer center (0.16), and treatment facility located in the Northeast region (0.54). Even after the introduction of novel agents, the rate of upfront AHCT in MM continues to increase annually. Significant disparities exist dependent on demographic, social, and geographic factors. © 2014 Wiley Periodicals, Inc.

Initial dislocation structure and dynamic dislocation multiplication in Mo single crystals

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

Hsiung, L M; Lassila, D H

Initial dislocation structure in annealed high-purity Mo single crystals and deformation substructure in a crystal subjected to 1% compression have been examined and studied in order to investigate dislocation multiplication mechanisms in the early stages of plastic deformation. The initial dislocation density is in a range of 10{sup 6} {approx} 10{sup 7} cm{sup -2}, and the dislocation structure is found to contain many grown-in superjogs along dislocation lines. The dislocation density increases to a range of 10{sup 8} {approx} 10{sup 9} cm{sup -2}, and the average jog height is also found to increase after compressing for a total strain ofmore » 1%. It is proposed that the preexisting jogged screw dislocations can act as (multiple) dislocation multiplication sources when deformed under quasi-static conditions. Both the jog height and length of link segment (between jogs) can increase by stress-induced jog coalescence, which takes place via the lateral migration (drift) of superjogs driven by unbalanced line-tension partials acting on link segments of unequal lengths. Applied shear stress begins to push each link segment to precede dislocation multiplication when link length and jog height are greater than critical lengths. This dynamic dislocation multiplication source is subsequently verified by direct simulations of dislocation dynamics under stress to be crucial in the early stages of plastic deformation in Mo single crystals.« less

Applying a Cognitive-Affective Model of Conceptual Change to Professional Development

NASA Astrophysics Data System (ADS)

Ebert, Ellen K.; Crippen, Kent J.

2010-04-01

This study evaluated Gregoire’s (2003) Cognitive-Affective Conceptual Change model (CAMCC) for predicting and assessing conceptual change in science teachers engaged in a long-term professional development project set in a large school district in the southwestern United States. A multiple case study method with data from three teacher participants was used to understand the process of integrating and applying a reform message of inquiry based science teaching. Data sources included: responses to example teaching scenarios, reflective essays, lesson plans, classroom observations, and action research projects. Findings show that the CAMCC functioned well in predicting how these teachers made decisions that impacted how they processed the reform message. When the reform message was communicated in such a way as to initiate stress appraisal, conceptual change occurred, producing changes in classroom practice. If the reform message did not initiate stress appraisal, teachers rejected the professional development message and developed heuristic responses. In order to further research and improve practice, propositions for assessments related to the CAMCC are provided.

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

Schnedermann, E.; Heinz, U.

We are analyzing the hydrodynamics of 200[ital A] GeV S+S collisions using a new approach which tries to quantify the uncertainties arising from the specific implementation of the hydrodynamical model. Based on a previous phenomenological analysis we use the global hydrodynamics model to show that the amount of initial flow, or initial energy density, cannot be determined from the hadronic momentum spectra. We additionally find that almost always a sizable transverse flow develops, which causes the system to freeze out, thereby limiting the flow velocity in itself. This freeze-out dominance in turn makes a distinction between a plasma and amore » hadron resonance gas equation of state very difficult, whereas a pure pion gas can easily be ruled out from present data. To complete the picture we also analyze particle multiplicity data, which suggest that chemical equilibrium is not reached with respect to the strange particles. However, the overpopulation of pions seems to be at most moderate, with a pion chemical potential far away from the Bose divergence.« less

Generalized teleparallel cosmology and initial singularity crossing

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

Awad, Adel; Nashed, Gamal, E-mail: Adel.Awad@bue.edu.eg, E-mail: gglnashed@sci.asu.edu.eg

We present a class of cosmological solutions for a generalized teleparallel gravity with f ( T )= T +α̃ (− T ) {sup n} , where α̃ is some parameter and n is an integer or half-integer. Choosing α̃ ∼ G {sup n} {sup −1}, where G is the gravitational constant, and working with an equation of state p = w ρ, one obtains a cosmological solution with multiple branches. The dynamics of the solution describes standard cosmology at late times, but the higher-torsion correction changes the nature of the initial singularity from big bang to a sudden singularity. Themore » milder behavior of the sudden singularity enables us to extend timelike or lightlike curves, through joining two disconnected branches of solution at the singularity, leaving the singularity traversable. We show that this extension is consistent with the field equations through checking the known junction conditions for generalized teleparallel gravity. This suggests that these solutions describe a contracting phase a prior to the expanding phase of the universe.« less

Parallel cascade selection molecular dynamics for efficient conformational sampling and free energy calculation of proteins

NASA Astrophysics Data System (ADS)

Kitao, Akio; Harada, Ryuhei; Nishihara, Yasutaka; Tran, Duy Phuoc

2016-12-01

Parallel Cascade Selection Molecular Dynamics (PaCS-MD) was proposed as an efficient conformational sampling method to investigate conformational transition pathway of proteins. In PaCS-MD, cycles of (i) selection of initial structures for multiple independent MD simulations and (ii) conformational sampling by independent MD simulations are repeated until the convergence of the sampling. The selection is conducted so that protein conformation gradually approaches a target. The selection of snapshots is a key to enhance conformational changes by increasing the probability of rare event occurrence. Since the procedure of PaCS-MD is simple, no modification of MD programs is required; the selections of initial structures and the restart of the next cycle in the MD simulations can be handled with relatively simple scripts with straightforward implementation. Trajectories generated by PaCS-MD were further analyzed by the Markov state model (MSM), which enables calculation of free energy landscape. The combination of PaCS-MD and MSM is reported in this work.

Abdominal aortic aneurysm events in the women's health initiative: cohort study.

PubMed

Lederle, Frank A; Larson, Joseph C; Margolis, Karen L; Allison, Matthew A; Freiberg, Matthew S; Cochrane, Barbara B; Graettinger, William F; Curb, J David

2008-10-14

To assess the association between potential risk factors and subsequent clinically important abdominal aortic aneurysm events (repairs and ruptures) in women. Large prospective observational cohort study with mean follow-up of 7.8 years. 40 clinical centres across the United States. 161 808 postmenopausal women aged 50-79 enrolled in the women's health initiative. Association of self reported or measured baseline variables with confirmed abdominal aortic aneurysm events assessed with multiple logistic regression. Events occurred in 184 women and were strongly associated with age and smoking. Ever smoking, current smoking, and amount smoked all contributed independent risk. Diabetes showed a negative association (odds ratio 0.29, 95% confidence interval 0.13, 0.68), as did postmenopausal hormone therapy. Positive associations were also seen for height, hypertension, cholesterol lowering treatment, and coronary and peripheral artery disease. Our findings confirm the strong positive associations of clinically important abdominal aortic aneurysm with age and smoking in women and the negative association with diabetes previously reported in men.

Transient Melting and Recrystallization of Semiconductor Nanocrystals Under Multiple Electron–Hole Pair Excitation

DOE PAGES

Kirschner, Matthew S.; Hannah, Daniel C.; Diroll, Benjamin T.; ...

2017-07-28

Ultrafast optical pump, X-ray diffraction probe experiments were performed on CdSe nanocrystal (NC) colloidal dispersions as functions of particle size, polytype, and pump fluence. Bragg peak shifts relate heating and peak amplitude reduction confers lattice disordering. For smaller NCs, melting initiates upon absorption of as few as ~15 electron-hole pair excitations per NC on average (0.89 excitations/nm 3 for a 1.5-nm radius) with roughly the same excitation density inducing melting for all examined NCs. Diffraction intensity recovery kinetics, attributable to recrystallization, occur over hundreds of picoseconds with slower recoveries for larger particles. Zincblende and wurtzite NCs revert to initial structuresmore » following intense photoexcitation suggesting melting occurs primarily at the surface, as supported by simulations. Electronic structure calculations relate significant band gap narrowing with decreased crystallinity. Here, these findings reflect the need to consider the physical stability of nanomaterials and related electronic impacts in high intensity excitation applications such as lasing and solid-state lighting.« less

Transient Melting and Recrystallization of Semiconductor Nanocrystals Under Multiple Electron–Hole Pair Excitation

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

Kirschner, Matthew S.; Hannah, Daniel C.; Diroll, Benjamin T.

Ultrafast optical pump, X-ray diffraction probe experiments were performed on CdSe nanocrystal (NC) colloidal dispersions as functions of particle size, polytype, and pump fluence. Bragg peak shifts relate heating and peak amplitude reduction confers lattice disordering. For smaller NCs, melting initiates upon absorption of as few as ~15 electron-hole pair excitations per NC on average (0.89 excitations/nm 3 for a 1.5-nm radius) with roughly the same excitation density inducing melting for all examined NCs. Diffraction intensity recovery kinetics, attributable to recrystallization, occur over hundreds of picoseconds with slower recoveries for larger particles. Zincblende and wurtzite NCs revert to initial structuresmore » following intense photoexcitation suggesting melting occurs primarily at the surface, as supported by simulations. Electronic structure calculations relate significant band gap narrowing with decreased crystallinity. Here, these findings reflect the need to consider the physical stability of nanomaterials and related electronic impacts in high intensity excitation applications such as lasing and solid-state lighting.« less

[Knowledge of emergency contraception among adolescents in public and private Brazilian high schools].

PubMed

Chofakian, Christiane Borges do Nascimento; Borges, Ana Luiza Vilela; Fujimori, Elizabeth; Hoga, Luiza Akiko Komura

2014-07-01

This study aimed to analyze the level of knowledge concerning emergency contraception among adolescents in public and private high schools. This was a cross-sectional study with 705 students 15 to 19 years of age enrolled in public and private high schools in a municipality in São Paulo State, Brazil. The authors used stratified probabilistic sampling by type of school and systematic sampling by class. Sexual initiation and use of emergency contraception were reported by 24.9% of private school students and 32% of public school students. The mean score on knowledge was 3.87 (SD = 2.12) in public schools and 5.14 (SD = 2.00) in private schools. Multiple linear regression analysis showed that higher scores on knowledge concerning emergency contraception were associated with: enrollment in private schools, female gender, older adolescents, sexual initiation, previous use of emergency contraception, and knowing someone who had used the method. The study concludes that few adolescents are properly informed about the method and that many harbor persistent misconceptions.

The relationship between psychosocial maturity and assertiveness in males and females.

PubMed

Goldman, J A; Olczak, P V

1981-02-01

The relationship between psychosocial maturity (psychological health) and assertiveness was investigated in a sample of United States college males and females. Results revealed a moderately high positive relationship between psychosocial maturity (PSM) and self-reported assertiveness on the Rathus and Galassi scales for both sexes. This relationship was slightly stronger (in terms of variance accounted for) for males than females, significant differences being obtained for Intimacy on the Rathus scale and PSM and Intimacy on the Galassi scale. Multiple regression analyses revealed that the personality components most consistently accounting for major portions of the variance in predicting male assertiveness scores on both the Rathus Assertiveness Schedule and the College Self-Expression Scale were Intimacy and Initiative, while in predicting female assertiveness, only Initiative was involved. The findings were related to previous research, recent work on the androgyny construct (instrumental vs. expressive behaviors), and exhortations for increased cooperation between schools of psychotherapy to establish it as a more unified discipline.

Family instability and early initiation of sexual activity in Western Kenya.

PubMed

Goldberg, Rachel E

2013-04-01

Epidemiological, economic, and social forces have produced high levels of volatility in family and household structure for young people growing up in sub-Saharan Africa in recent decades. However, scholarship on the family to date has not examined the influence of this family instability on young people's well-being. The current study employs unique life history calendar data from Western Kenya to investigate the relationship between instability in caregiving and early initiation of sexual activity. It draws on a body of work on parental union instability in the United States, and examines new dimensions of family change. Analyses reveal a positive association between transitions in primary caregiver and the likelihood of early sexual debut that is rapidly manifested following caregiver change and persists for a short period. The association is strongest at early ages, and there is a cumulative effect of multiple caregiver changes. The results highlight the importance of studying family stability in sub-Saharan Africa, as distinct from family structure, and for attention to dimensions such as age and recency.

Transient Melting and Recrystallization of Semiconductor Nanocrystals Under Multiple Electron-Hole Pair Excitation.

PubMed

Kirschner, Matthew S; Hannah, Daniel C; Diroll, Benjamin T; Zhang, Xiaoyi; Wagner, Michael J; Hayes, Dugan; Chang, Angela Y; Rowland, Clare E; Lethiec, Clotilde M; Schatz, George C; Chen, Lin X; Schaller, Richard D

2017-09-13

Ultrafast optical pump, X-ray diffraction probe experiments were performed on CdSe nanocrystal (NC) colloidal dispersions as functions of particle size, polytype, and pump fluence. Bragg peak shifts related to heating and peak amplitude reduction associated with lattice disordering are observed. For smaller NCs, melting initiates upon absorption of as few as ∼15 electron-hole pair excitations per NC on average (0.89 excitations/nm 3 for a 1.5 nm radius) with roughly the same excitation density inducing melting for all examined NCs. Diffraction intensity recovery kinetics, attributable to recrystallization, occur over hundreds of picoseconds with slower recoveries for larger particles. Zincblende and wurtzite NCs revert to initial structures following intense photoexcitation suggesting melting occurs primarily at the surface, as supported by simulations. Electronic structure calculations relate significant band gap narrowing with decreased crystallinity. These findings reflect the need to consider the physical stability of nanomaterials and related electronic impacts in high intensity excitation applications such as lasing and solid-state lighting.

Reducing Unnecessary Portable Pelvic Radiographs in Trauma Patients: A Resident-Driven Quality Improvement Initiative.

PubMed

Langer, Jessica M; Tsai, Emily B; Luhar, Aarti; McWilliams, Justin; Motamedi, Kambiz

2015-09-01

Quality improvement is increasingly important in the changing health care climate. We aim to establish a methodology and identify critical factors leading to successful implementation of a resident-led radiology quality improvement intervention at the institutional level. Under guidance of faculty mentors, the first-year radiology residents developed a quality improvement initiative to decrease unnecessary STAT pelvic radiographs (PXRs) in hemodynamically stable trauma patients who would additionally receive STAT pelvic CT scans. Development and implementation of this initiative required multiple steps, including: establishing resident and faculty leadership, gathering evidence from published literature, cultivating multidisciplinary support, and developing and implementing an institution-wide ordering algorithm. A visual aid and brief questionnaire were distributed to clinicians for use during treatment of trauma cases to ensure sustainability of the initiative. At multiple time points, pre- and post-intervention, residents performed a retrospective chart review to evaluate changes in imaging-ordering trends for trauma patients. Chart review showed a decline in the number of PXRs for hemodynamically stable trauma patients, as recommended in the ordering algorithm: 78% of trauma patients received both a PXR and a pelvic CT scan in the first 24 hours of the initiative, compared with 26% at 1 month; 24% at 6 months; and 18% at 10 to 12 months postintervention. The resident-led radiology quality improvement initiative created a shift in ordering culture at an institutional level. Development and implementation of this algorithm exemplified the impact of a multidisciplinary collaborative effort involving multiple departments and multiple levels of the medical hierarchy. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Recent Initiatives in the Republic of Srpska to Enhance Appropriate Use of Antibiotics in Ambulatory Care; Their Influence and Implications.

PubMed

Bojanić, Ljubica; Marković-Peković, Vanda; Škrbić, Ranko; Stojaković, Nataša; Ðermanović, Mirjana; Bojanić, Janja; Fürst, Jurij; Kurdi, Amanj B; Godman, Brian

2018-01-01

Introduction: There are increasing concerns world-wide with growing rates of antibiotic resistance necessitating urgent action. There have been a number of initiatives in the Republic of Srpska in recent years to address this and improve rational antibiotic prescribing and dispensing despite limited resources to fund multiple initiatives. Objective: Analyse antibiotic utilization patterns in the Republic of Srpska following these multiple initiatives as a basis for developing future programmes in the Republic if needed. Methods: Observational retrospective study of total outpatient antibiotic utilization from 2010 to 2015, based on data obtained from the Public Health Institute, alongside documentation of ongoing initiatives to influence utilization. The quality of antibiotic utilization principally assessed according to ESAC, ECDC, and WHO quality indicators and DU 90% (the drug utilization 90%) profile as well as vs. neighboring countries. Results: Following multiple initiatives, antibiotic utilization remained relatively stable in the Republic at 15.6 to 18.4 DIDs, with a decreasing trend in recent years, with rates comparable or lower than neighboring countries. Amoxicillin and the penicillins accounted for 29-40 and 50% of total utilization, respectively. Overall, limited utilization of co-amoxiclav (7-11%), cephalosporins, macrolides, and quinolones, as well as low use of third and fourth generation cephalosporins vs. first and second cephalosporins. However, increasing utilization of co-amoxiclav and azithromycin, as well as higher rates of quinolone utilization compared to some countries, was seen. Conclusions: Multiple interventions in the Republic of Srpska in recent years have resulted in one of the lowest utilization of antibiotics when compared with similar countries, acting as an exemplar to others. However, there are some concerns with current utilization of co-amoxiclav and azithromycin which are being addressed. This will be the subject of future research activities.

RAS Initiative - Events

Cancer.gov

The NCI RAS Initiative has organized multiple events with outside experts to discuss how the latest scientific and technological breakthroughs can be applied to discover vulnerabilities in RAS-driven cancers.

Role of Perturbing Ocean Initial Condition in Simulated Regional Sea Level Change

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

Hu, Aixue; Meehl, Gerald; Stammer, Detlef

Multiple lines of observational evidence indicate that the global climate has been getting warmer since the early 20th century. This warmer climate has led to a global mean sea level rise of about 18 cm during the 20th century, and over 6 cm for the first 15 years of the 21st century. Regionally the sea level rise is not uniform due in large part to internal climate variability. To better serve the community, the uncertainties of predicting/projecting regional sea level changes associated with internal climate variability need to be quantified. Previous research on this topic has used single-model large ensemblesmore » with perturbed atmospheric initial conditions (ICs). Here we compare uncertainties associated with perturbing ICs in just the atmosphere and just the ocean using a state-of-the-art coupled climate model. We find that by perturbing the oceanic ICs, the uncertainties in regional sea level changes increase compared to those with perturbed atmospheric ICs. In order for us to better assess the full spectrum of the impacts of such internal climate variability on regional and global sea level rise, approaches that involve perturbing both atmospheric and oceanic initial conditions are thus necessary.« less

Role of Perturbing Ocean Initial Condition in Simulated Regional Sea Level Change

DOE PAGES

Hu, Aixue; Meehl, Gerald; Stammer, Detlef; ...

2017-06-05

Multiple lines of observational evidence indicate that the global climate has been getting warmer since the early 20th century. This warmer climate has led to a global mean sea level rise of about 18 cm during the 20th century, and over 6 cm for the first 15 years of the 21st century. Regionally the sea level rise is not uniform due in large part to internal climate variability. To better serve the community, the uncertainties of predicting/projecting regional sea level changes associated with internal climate variability need to be quantified. Previous research on this topic has used single-model large ensemblesmore » with perturbed atmospheric initial conditions (ICs). Here we compare uncertainties associated with perturbing ICs in just the atmosphere and just the ocean using a state-of-the-art coupled climate model. We find that by perturbing the oceanic ICs, the uncertainties in regional sea level changes increase compared to those with perturbed atmospheric ICs. In order for us to better assess the full spectrum of the impacts of such internal climate variability on regional and global sea level rise, approaches that involve perturbing both atmospheric and oceanic initial conditions are thus necessary.« less

The operations of quantum logic gates with pure and mixed initial states.

PubMed

Chen, Jun-Liang; Li, Che-Ming; Hwang, Chi-Chuan; Ho, Yi-Hui

2011-04-07

The implementations of quantum logic gates realized by the rovibrational states of a C(12)O(16) molecule in the X((1)Σ(+)) electronic ground state are investigated. Optimal laser fields are obtained by using the modified multitarget optimal theory (MTOCT) which combines the maxima of the cost functional and the fidelity for state and quantum process. The projection operator technique together with modified MTOCT is used to get optimal laser fields. If initial states of the quantum gate are pure states, states at target time approach well to ideal target states. However, if the initial states are mixed states, the target states do not approach well to ideal ones. The process fidelity is introduced to investigate the reliability of the quantum gate operation driven by the optimal laser field. We found that the quantum gates operate reliably whether the initial states are pure or mixed.

Observability and Estimation of Distributed Space Systems via Local Information-Exchange Networks

NASA Technical Reports Server (NTRS)

Fathpour, Nanaz; Hadaegh, Fred Y.; Mesbahi, Mehran; Rahmani, Amirreza

2011-01-01

Spacecraft formation flying involves the coordination of states among multiple spacecraft through relative sensing, inter-spacecraft communication, and control. Most existing formation-flying estimation algorithms can only be supported via highly centralized, all-to-all, static relative sensing. New algorithms are proposed that are scalable, modular, and robust to variations in the topology and link characteristics of the formation exchange network. These distributed algorithms rely on a local information exchange network, relaxing the assumptions on existing algorithms. Distributed space systems rely on a signal transmission network among multiple spacecraft for their operation. Control and coordination among multiple spacecraft in a formation is facilitated via a network of relative sensing and interspacecraft communications. Guidance, navigation, and control rely on the sensing network. This network becomes more complex the more spacecraft are added, or as mission requirements become more complex. The observability of a formation state was observed by a set of local observations from a particular node in the formation. Formation observability can be parameterized in terms of the matrices appearing in the formation dynamics and observation matrices. An agreement protocol was used as a mechanism for observing formation states from local measurements. An agreement protocol is essentially an unforced dynamic system whose trajectory is governed by the interconnection geometry and initial condition of each node, with a goal of reaching a common value of interest. The observability of the interconnected system depends on the geometry of the network, as well as the position of the observer relative to the topology. For the first time, critical GN&C (guidance, navigation, and control estimation) subsystems are synthesized by bringing the contribution of the spacecraft information-exchange network to the forefront of algorithmic analysis and design. The result is a formation estimation algorithm that is modular and robust to variations in the topology and link properties of the underlying formation network.

Fate of a gray soliton in a quenched Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Gamayun, O.; Bezvershenko, Yu. V.; Cheianov, V.

2015-03-01

We investigate the destiny of a gray soliton in a repulsive one-dimensional Bose-Einstein condensate undergoing a sudden quench of the nonlinearity parameter. The outcome of the quench is found to depend dramatically on the ratio η of the final and initial values of the speed of sound. For integer η the soliton splits into exactly 2 η -1 solitons. For noninteger η the soliton decays into multiple solitons and Bogoliubov modes. The case of integer η is analyzed in detail. The parameters of solitons in the out state are found explicitly. Our approach exploits the inverse scattering method and can be easily used for similar quenches in any classical integrable system.

Dynamical phases in a one-dimensional chain of heterospecies Rydberg atoms with next-nearest-neighbor interactions

NASA Astrophysics Data System (ADS)

Qian, Jing; Zhang, Lu; Zhai, Jingjing; Zhang, Weiping

2015-12-01

We theoretically investigate the dynamical phase diagram of a one-dimensional chain of laser-excited two-species Rydberg atoms. The existence of a variety of unique dynamical phases in the experimentally achievable parameter region is predicted under the mean-field approximation, and the change in those phases when the effect of the next-nearest-neighbor interaction is included is further discussed. In particular, we find that the com-petition of the strong Rydberg-Rydberg interactions and the optical excitation imbalance can lead to the presence of complex multiple chaotic phases, which are highly sensitive to the initial Rydberg-state population and the strength of the next-nearest-neighbor interactions.

Florida's tuberculosis epidemic. Public health response.

PubMed

Witte, J J; Bigler, W J

1994-03-01

Florida ranked fourth in the nation with 1,707 tuberculosis cases reported in 1992 for a rate of 12.7 per 100,000 population. Thirteen percent of these patients had AIDS. Recent cases in prisons, shelters, hospitals and schools have stimulated interest and media coverage. Resurgence of strains of multiple-drug resistant tuberculosis is a serious concern. The Florida Department of Health and Rehabilitative Services, in collaboration with allied agencies, has utilized several initiatives in response. The most significant, Tuberculosis Epidemic Containment Plan, details intervention strategies needed to eliminate TB in the state by the year 2010. Successful implementation depends upon local TB prevention and control coalitions that include private and public sector providers.

The end of gonad-centric sex determination in mammals

PubMed Central

Arnold, Arthur P.

2011-01-01

The 20th century theory of mammalian sex determination states that the embryo is sexually indifferent until the differentiation of gonads, after which sex differences in phenotype are caused by differential effects of gonadal hormones. That theory is inadequate because some sex differences precede differentiation of the gonads and/or are determined by non-gonadal effects of the sexual inequality in number and type of sex chromosomes. A general theory of sex determination is proposed, which recognizes multiple parallel primary sex-determining pathways initiated by genes or factors encoded by the sex chromosomes. The separate sex-specific pathways interact to synergize with or antagonize each other, enhancing or reducing sex differences in phenotype. PMID:22078126

Something fishy: an unusual Erysipelothrix rhusiopathiae infection in an immunocompromised individual.

PubMed

Sinclair, Marie; Hawkins, Angela; Testro, Adam

2013-04-03

A 39-year-old man with a history of Crohn's disease presented to the emergency department with a 12-h history of worsening febrile illness. He deteriorated rapidly with progression to sepsis and was admitted to the intensive care unit. Initial treatment comprised broad spectrum antibiotics and inotropic support resulting in rapid improvement. With the immunocompromised state of the patient, and multiple blood cultures revealing Erysipelothrix rhusiopathiae, a detailed history disclosed a recent injury sustained from a fishing wire as the probable source of an infection. Treatment was narrowed to target the identified pathogen, the patient made a full recovery, and was counselled to be more cautious in future fishing activities.

Something fishy: an unusual Erysipelothrix rhusiopathiae infection in an immunocompromised individual

PubMed Central

Sinclair, Marie; Hawkins, Angela; Testro, Adam

2013-01-01

A 39-year-old man with a history of Crohn's disease presented to the emergency department with a 12-h history of worsening febrile illness. He deteriorated rapidly with progression to sepsis and was admitted to the intensive care unit. Initial treatment comprised broad spectrum antibiotics and inotropic support resulting in rapid improvement. With the immunocompromised state of the patient, and multiple blood cultures revealing Erysipelothrix rhusiopathiae, a detailed history disclosed a recent injury sustained from a fishing wire as the probable source of an infection. Treatment was narrowed to target the identified pathogen, the patient made a full recovery, and was counselled to be more cautious in future fishing activities. PMID:23559657

Critical Care for the Patient With Multiple Trauma.

PubMed

Radomski, Michal; Zettervall, Sara; Schroeder, Mary Elizabeth; Messing, Jonathan; Dunne, James; Sarani, Babak

2016-06-01

Trauma remains the leading cause of death worldwide and the leading cause of death in those less than 44 years old in the United States. Admission to a verified trauma center has been shown to decrease mortality following a major injury. This decrease in mortality has been a direct result of improvements in the initial evaluation and resuscitation from injury as well as continued advances in critical care. As such, it is vital that intensive care practitioners be familiar with various types of injuries and their associated treatment strategies as well as their potential complications in order to minimize the morbidity and mortality frequently seen in this patient population. © The Author(s) 2015.

The Role of TLR2 in Infection and Immunity

PubMed Central

Oliveira-Nascimento, Laura; Massari, Paola; Wetzler, Lee M.

2012-01-01

Toll-like receptors (TLRs) are recognition molecules for multiple pathogens, including bacteria, viruses, fungi, and parasites. TLR2 forms heterodimers with TLR1 and TLR6, which is the initial step in a cascade of events leading to significant innate immune responses, development of adaptive immunity to pathogens and protection from immune sequelae related to infection with these pathogens. This review will discuss the current status of TLR2 mediated immune responses by recognition of pathogen-associated molecular patterns (PAMPS) on these organisms. We will emphasize both canonical and non-canonical responses to TLR2 ligands with emphasis on whether the inflammation induced by these responses contributes to the disease state or to protection from diseases. PMID:22566960

Age as a moderator of relations of physical self-concept and mood changes associated with 10 weeks of programmed exercise in women.

PubMed

Annesi, James J; Westcott, Wayne L

2005-12-01

Significant correlations were found between reported changes in scores on the Physical Self-concept scale of the Tennessee Self-concept Scale, with those on the Depression (r=-.34) and Total Mood Disturbance (r=-.38) scales of the Profile of Mood States, for 35 women who initiated a structured exercise program. Accounting for age in simultaneous multiple regression equations added to the explained variance in changes in both Depression (R2=.29) and Total Mood Disturbance (R2=.18) scores. Findings supported propositions of social cognitive theory and self-efficacy theory. Limitations and the need for replication and extension were discussed.

Assessment of the Sustainability Capacity of a Coordinated Approach to Chronic Disease Prevention.

PubMed

Moreland-Russell, Sarah; Combs, Todd; Polk, LaShaun; Dexter, Sarah

This article outlines some factors that influenced the sustainability capacity of a coordinated approach to chronic disease prevention in state and territory health departments. This study involved a cross-sectional design and mixed-methods approach. Quantitative data were collected using the Program Sustainability Assessment Tool (PSAT), a 40-item multiple-choice instrument that assesses 8 domains of sustainability capacity (environmental support, funding stability, partnerships, organizational capacity, program evaluation, program adaptation, communications, and strategic planning). Qualitative data were collected via phone interviews. The PSAT was administered to staff and stakeholders from public health departments in 50 US states, District of Columbia, and Puerto Rico, who were involved in the implementation of coordinated chronic disease programs. Phone interviews were conducted with program coordinators in each state. Sustainability score patterns and state-level categorical results, as well as strengths and opportunities for improvement across the 8 program sustainability domains, were explored. On average, programs reported the strongest sustainability capacity in the domains of program adaptation, environmental support, and organizational capacity, while funding stability, strategic planning, and communications yielded lowest scores, indicating weakest capacity. Scores varied the most by state in environmental support and strategic planning. The PSAT results highlight the process through which states approached the sustainability of coordinated chronic disease initiatives. This process included an initial focus on program evaluation and partnerships with transfer of priority to long-term strategic planning, communications, and funding stability to further establish coordinated chronic disease efforts. Qualitative interviews provided further context to PSAT results, indicating that leadership, communications, partnerships, funding stability, and policy change were perceived as keys to success of the transition. Integrating these findings into future efforts may help those in transition establish greater sustainability capacity. The PSAT results and interviews provide insight into the capacity for sustainability for programs transitioning from traditional siloed programs to coordinated chronic disease programs.

Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae

PubMed Central

Waldbusser, George G.; Hales, Burke; Langdon, Chris J.; Haley, Brian A.; Schrader, Paul; Brunner, Elizabeth L.; Gray, Matthew W.; Miller, Cale A.; Gimenez, Iria; Hutchinson, Greg

2015-01-01

Ocean acidification (OA) is altering the chemistry of the world’s oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by saturation state. PMID:26061095

Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

PubMed

Waldbusser, George G; Hales, Burke; Langdon, Chris J; Haley, Brian A; Schrader, Paul; Brunner, Elizabeth L; Gray, Matthew W; Miller, Cale A; Gimenez, Iria; Hutchinson, Greg

2015-01-01

Ocean acidification (OA) is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by saturation state.

Initial correlations in open-systems dynamics: The Jaynes-Cummings model

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

Smirne, Andrea; Vacchini, Bassano; INFN, Sezione di Milano, Via Celoria 16, I-20133 Milano

2010-12-15

Employing the trace distance as a measure for the distinguishability of quantum states, we study the influence of initial correlations on the dynamics of open systems. We concentrate on the Jaynes-Cummings model for which the knowledge of the exact joint dynamics of system and reservoir allows the treatment of initial states with arbitrary correlations. As a measure for the correlations in the initial state we consider the trace distance between the system-environment state and the product of its marginal states. In particular, we examine the correlations contained in the thermal equilibrium state for the total system, analyze their dependence onmore » the temperature and on the coupling strength, and demonstrate their connection to the entanglement properties of the eigenstates of the Hamiltonian. A detailed study of the time dependence of the distinguishability of the open system states evolving from the thermal equilibrium state and its corresponding uncorrelated product state shows that the open system dynamically uncovers typical features of the initial correlations.« less

Relations between heat exchange and Rényi divergences

NASA Astrophysics Data System (ADS)

Wei, Bo-Bo

2018-04-01

In this work, we establish an exact relation which connects the heat exchange between two systems initialized in their thermodynamic equilibrium states at different temperatures and the Rényi divergences between the initial thermodynamic equilibrium state and the final nonequilibrium state of the total system. The relation tells us that the various moments of the heat statistics are determined by the Renyi divergences between the initial equilibrium state and the final nonequilibrium state of the global system. In particular the average heat exchange is quantified by the relative entropy between the initial equilibrium state and the final nonequilibrium state of the global system. The relation is applicable to both finite classical systems and finite quantum systems.

Relations between heat exchange and Rényi divergences.

PubMed

Wei, Bo-Bo

2018-04-01

In this work, we establish an exact relation which connects the heat exchange between two systems initialized in their thermodynamic equilibrium states at different temperatures and the Rényi divergences between the initial thermodynamic equilibrium state and the final nonequilibrium state of the total system. The relation tells us that the various moments of the heat statistics are determined by the Renyi divergences between the initial equilibrium state and the final nonequilibrium state of the global system. In particular the average heat exchange is quantified by the relative entropy between the initial equilibrium state and the final nonequilibrium state of the global system. The relation is applicable to both finite classical systems and finite quantum systems.

On the adiabatic limit of Hadamard states

NASA Astrophysics Data System (ADS)

Drago, Nicolò; Gérard, Christian

2017-08-01

We consider the adiabatic limit of Hadamard states for free quantum Klein-Gordon fields, when the background metric and the field mass are slowly varied from their initial to final values. If the Klein-Gordon field stays massive, we prove that the adiabatic limit of the initial vacuum state is the (final) vacuum state, by extending to the symplectic framework the adiabatic theorem of Avron-Seiler-Yaffe. In cases when only the field mass is varied, using an abstract version of the mode decomposition method we can also consider the case when the initial or final mass vanishes, and the initial state is either a thermal state or a more general Hadamard state.

Hypercoagulable states in patients with multiple myeloma can affect the thalidomide-associated venous thromboembolism.

PubMed

Talamo, Giampaolo P; Ibrahim, Sulfi; Claxton, David; Tricot, Guido J; Fink, Louis M; Zangari, Maurizio

2009-07-01

The therapeutic use of thalidomide in patients with multiple myeloma is often complicated by the development of venous thromboembolism. The objective of the present study was to identify hypercoagulable states associated with development of venous thromboembolism in thalidomide-treated multiple myeloma patients. We screened 49 consecutive multiple myeloma patients treated with thalidomide at baseline for hypercoagulability. With a median follow-up of 11 months, 10 of 49 multiple myeloma patients developed a thrombotic episode. Laboratory assays revealed an underlying abnormality in nine of the 10 patients; hypercoagulable screenings were normal in 36 of the 39 patients who did not develop venous thromboembolism (P < 0.0001). Our retrospective study results suggest that the multiple myeloma patients with thromboembolic complications during treatment with thalidomide have a frequent concomitant underlying thrombophilic state.

The New Hampshire retail competition pilot program and the role of green marketing

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

Holt, E.A.; Fang, J.M.

1997-11-01

Most states in the US are involved in electric industry restructuring, from considering the pros and cons in regulatory dockets to implementing legislative mandates for full restructuring and retail access for all consumers. Several states and utilities have initiated pilot programs in which multiple suppliers or service providers may compete for business and some utility customers can choose among competing suppliers. The State of New Hampshire has been experimenting with a pilot program, mandated by the State Legislature in 1995 and implemented by the New Hampshire Public Utilities Commission (NHPUC), before it implements full retail access. Green marketing, an attemptmore » to characterize the supplier or service provider as environmentally friendly without referring to the energy resource used to generate electricity, was used by several suppliers or service providers to attract customers. This appeal to environmental consumerism was moderately successful, but it raised a number of consumer protection and public policy issues. This issue brief examines the marketing methods used in New Hampshire and explores what green marketing might mean for the development of renewable energy generation. It also addresses the issues raised and their implications.« less

Nanosecond laser-cluster interactions at 109-1012 W/cm 2

NASA Astrophysics Data System (ADS)

Singh, Rohtash; Tripathi, V. K.; Vatsa, R. K.; Das, D.

2017-08-01

An analytical model and a numerical code are developed to study the evolution of multiple charge states of ions by irradiating clusters of atoms of a high atomic number (e.g., Xe) by 1.06 μm and 0.53 μm nanosecond laser pulses of an intensity in the range of 109-1012 W/cm 2 . The laser turns clusters into plasma nanoballs. Initially, the momentum randomizing collisions of electrons are with neutrals, but soon these are taken over by collisions with ions. The ionization of an ion to the next higher state of ionization is taken to be caused by an energetic free electron impact, and the rates of impact ionization are suitably modelled by having an inverse exponential dependence of ionizing collision frequency on the ratio of ionization potential to electron temperature. Cluster expansion led adiabatic cooling is a major limiting mechanism on electron temperature. In the intensity range considered, ionization states up to 7 are expected with nanosecond pulses. Another possible mechanism, filamentation of the laser, has also been considered to account for the observation of higher charged states. However, filamentation is seen to be insufficient to cause substantial local enhancement in the intensity to affect electron heating rates.

Selectivity of Electronic Coherence and Attosecond Ionization Delays in Strong-Field Double Ionization

NASA Astrophysics Data System (ADS)

Kobayashi, Yuki; Reduzzi, Maurizio; Chang, Kristina F.; Timmers, Henry; Neumark, Daniel M.; Leone, Stephen R.

2018-06-01

Experiments are presented on real-time probing of coherent electron dynamics in xenon initiated by strong-field double ionization. Attosecond transient absorption measurements allow for characterization of electronic coherences as well as relative ionization timings in multiple electronic states of Xe+ and Xe2 + . A high degree of coherence g =0.4 is observed between P3 2 0-P3 0 0 of Xe2 + , whereas for other possible pairs of states the coherences are below the detection limits of the experiments. A comparison of the experimental results with numerical simulations based on an uncorrelated electron-emission model shows that the coherences produced by strong-field double ionization are more selective than predicted. Surprisingly short ionization time delays, 0.85 fs, 0.64 fs, and 0.75 fs relative to Xe+ formation, are also measured for the P2 3 , P0 3 , and P1 3 states of Xe2 + , respectively. Both the unpredicted selectivity in the formation of coherence and the subfemtosecond time delays of specific states provide new insight into correlated electron dynamics in strong-field double ionization.

Switching neuronal state: optimal stimuli revealed using a stochastically-seeded gradient algorithm.

PubMed

Chang, Joshua; Paydarfar, David

2014-12-01

Inducing a switch in neuronal state using energy optimal stimuli is relevant to a variety of problems in neuroscience. Analytical techniques from optimal control theory can identify such stimuli; however, solutions to the optimization problem using indirect variational approaches can be elusive in models that describe neuronal behavior. Here we develop and apply a direct gradient-based optimization algorithm to find stimulus waveforms that elicit a change in neuronal state while minimizing energy usage. We analyze standard models of neuronal behavior, the Hodgkin-Huxley and FitzHugh-Nagumo models, to show that the gradient-based algorithm: (1) enables automated exploration of a wide solution space, using stochastically generated initial waveforms that converge to multiple locally optimal solutions; and (2) finds optimal stimulus waveforms that achieve a physiological outcome condition, without a priori knowledge of the optimal terminal condition of all state variables. Analysis of biological systems using stochastically-seeded gradient methods can reveal salient dynamical mechanisms underlying the optimal control of system behavior. The gradient algorithm may also have practical applications in future work, for example, finding energy optimal waveforms for therapeutic neural stimulation that minimizes power usage and diminishes off-target effects and damage to neighboring tissue.

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

LeBaron, Robin; Saul-Rinaldi, Kara

There has never been a better time to launch initiatives to promote residential energy efficiency savings. Over the past several decades, residential retrofit programs have demonstrated that energy efficiency measures contribute to achieving multiple benefits, including but not limited to reductions in home energy consumption, stabilization improvements for the grid by shaving peak loads, saving consumers millions on utility bills, and significantly reducing carbon emissions. Although a number of barriers to widespread uptake of home energy upgrades persist, the lessons learned as a result of the 2009 stimulus funding1 have resulted in a set of policy approaches that create newmore » strategies for taking residential energy efficiency to scale.2 The identification of these approaches is well timed; energy efficiency is often the least expensive and most cost effective way to comply with a variety of federal, state and local policies. This Guide is designed to help state and local policymakers to take full advantage of new policy developments by providing them with a comprehensive set of tools to support launching or accelerating residential energy efficiency programs. It is written primarily for state and local policymakers, including state and local executives, legislators, public utility commissioners, and the staff who advise them.« less

A System-Oriented Approach for the Optimal Control of Process Chains under Stochastic Influences

NASA Astrophysics Data System (ADS)

Senn, Melanie; Schäfer, Julian; Pollak, Jürgen; Link, Norbert

2011-09-01

Process chains in manufacturing consist of multiple connected processes in terms of dynamic systems. The properties of a product passing through such a process chain are influenced by the transformation of each single process. There exist various methods for the control of individual processes, such as classical state controllers from cybernetics or function mapping approaches realized by statistical learning. These controllers ensure that a desired state is obtained at process end despite of variations in the input and disturbances. The interactions between the single processes are thereby neglected, but play an important role in the optimization of the entire process chain. We divide the overall optimization into two phases: (1) the solution of the optimization problem by Dynamic Programming to find the optimal control variable values for each process for any encountered end state of its predecessor and (2) the application of the optimal control variables at runtime for the detected initial process state. The optimization problem is solved by selecting adequate control variables for each process in the chain backwards based on predefined quality requirements for the final product. For the demonstration of the proposed concept, we have chosen a process chain from sheet metal manufacturing with simplified transformation functions.

Accounting for disturbance history in models: using remote sensing to constrain carbon and nitrogen pool spin-up.

PubMed

Hanan, Erin J; Tague, Christina; Choate, Janet; Liu, Mingliang; Kolden, Crystal; Adam, Jennifer

2018-03-24

Disturbances such as wildfire, insect outbreaks, and forest clearing, play an important role in regulating carbon, nitrogen, and hydrologic fluxes in terrestrial watersheds. Evaluating how watersheds respond to disturbance requires understanding mechanisms that interact over multiple spatial and temporal scales. Simulation modeling is a powerful tool for bridging these scales; however, model projections are limited by uncertainties in the initial state of plant carbon and nitrogen stores. Watershed models typically use one of two methods to initialize these stores: spin-up to steady state or remote sensing with allometric relationships. Spin-up involves running a model until vegetation reaches equilibrium based on climate. This approach assumes that vegetation across the watershed has reached maturity and is of uniform age, which fails to account for landscape heterogeneity and non-steady-state conditions. By contrast, remote sensing, can provide data for initializing such conditions. However, methods for assimilating remote sensing into model simulations can also be problematic. They often rely on empirical allometric relationships between a single vegetation variable and modeled carbon and nitrogen stores. Because allometric relationships are species- and region-specific, they do not account for the effects of local resource limitation, which can influence carbon allocation (to leaves, stems, roots, etc.). To address this problem, we developed a new initialization approach using the catchment-scale ecohydrologic model RHESSys. The new approach merges the mechanistic stability of spin-up with the spatial fidelity of remote sensing. It uses remote sensing to define spatially explicit targets for one or several vegetation state variables, such as leaf area index, across a watershed. The model then simulates the growth of carbon and nitrogen stores until the defined targets are met for all locations. We evaluated this approach in a mixed pine-dominated watershed in central Idaho, and a chaparral-dominated watershed in southern California. In the pine-dominated watershed, model estimates of carbon, nitrogen, and water fluxes varied among methods, while the target-driven method increased correspondence between observed and modeled streamflow. In the chaparral watershed, where vegetation was more homogeneously aged, there were no major differences among methods. Thus, in heterogeneous, disturbance-prone watersheds, the target-driven approach shows potential for improving biogeochemical projections. © 2018 by the Ecological Society of America.

The interaction of DiaA and DnaA regulates the replication cycle in E. coli by directly promoting ATP–DnaA-specific initiation complexes

PubMed Central

Keyamura, Kenji; Fujikawa, Norie; Ishida, Takuma; Ozaki, Shogo; Su’etsugu, Masayuki; Fujimitsu, Kazuyuki; Kagawa, Wataru; Yokoyama, Shigeyuki; Kurumizaka, Hitoshi; Katayama, Tsutomu

2007-01-01

Escherichia coli DiaA is a DnaA-binding protein that is required for the timely initiation of chromosomal replication during the cell cycle. In this study, we determined the crystal structure of DiaA at 1.8 Å resolution. DiaA forms a homotetramer consisting of a symmetrical pair of homodimers. Mutational analysis revealed that the DnaA-binding activity and formation of homotetramers are required for the stimulation of initiation by DiaA. DiaA tetramers can bind multiple DnaA molecules simultaneously. DiaA stimulated the assembly of multiple DnaA molecules on oriC, conformational changes in ATP–DnaA-specific initiation complexes, and unwinding of oriC duplex DNA. The mutant DiaA proteins are defective in these stimulations. DiaA associated also with ADP–DnaA, and stimulated the assembly of inactive ADP–DnaA–oriC complexes. Specific residues in the putative phosphosugar-binding motif of DiaA were required for the stimulation of initiation and formation of ATP–DnaA-specific–oriC complexes. Our data indicate that DiaA regulates initiation by a novel mechanism, in which DiaA tetramers most likely bind to multiple DnaA molecules and stimulate the assembly of specific ATP–DnaA–oriC complexes. These results suggest an essential role for DiaA in the promotion of replication initiation in a cell cycle coordinated manner. PMID:17699754

Vehicle electrical system state controller

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

Bissontz, Jay E.

A motor vehicle electrical power distribution system includes a plurality of distribution sub-systems, an electrical power storage sub-system and a plurality of switching devices for selective connection of elements of and loads on the power distribution system to the electrical power storage sub-system. A state transition initiator provides inputs to control system operation of switching devices to change the states of the power distribution system. The state transition initiator has a plurality of positions selection of which can initiate a state transition. The state transition initiator can emulate a four position rotary ignition switch. Fail safe power cutoff switches providemore » high voltage switching device protection.« less

Linked-List-Based Multibody Dynamics (MBDyn) Engine

NASA Technical Reports Server (NTRS)

MacLean, John; Brain, Thomas; Wuiocho, Leslie; Huynh, An; Ghosh, Tushar

2012-01-01

This new release of MBDyn is a software engine that calculates the dynamics states of kinematic, rigid, or flexible multibody systems. An MBDyn multibody system may consist of multiple groups of articulated chains, trees, or closed-loop topologies. Transient topologies are handled through conservation of energy and momentum. The solution for rigid-body systems is exact, and several configurable levels of nonlinear term fidelity are available for flexible dynamics systems. The algorithms have been optimized for efficiency and can be used for both non-real-time (NRT) and real-time (RT) simulations. Interfaces are currently compatible with NASA's Trick Simulation Environment. This new release represents a significant advance in capability and ease of use. The two most significant new additions are an application programming interface (API) that clarifies and simplifies use of MBDyn, and a link-list infrastructure that allows a single MBDyn instance to propagate an arbitrary number of interacting groups of multibody top ologies. MBDyn calculates state and state derivative vectors for integration using an external integration routine. A Trickcompatible interface is provided for initialization, data logging, integration, and input/output.

Replication of the Escherichia coli chromosome in RNase HI-deficient cells: multiple initiation regions and fork dynamics.

PubMed

Maduike, Nkabuije Z; Tehranchi, Ashley K; Wang, Jue D; Kreuzer, Kenneth N

2014-01-01

DNA replication in Escherichia coli is normally initiated at a single origin, oriC, dependent on initiation protein DnaA. However, replication can be initiated elsewhere on the chromosome at multiple ectopic oriK sites. Genetic evidence indicates that initiation from oriK depends on RNA-DNA hybrids (R-loops), which are normally removed by enzymes such as RNase HI to prevent oriK from misfiring during normal growth. Initiation from oriK sites occurs in RNase HI-deficient mutants, and possibly in wild-type cells under certain unusual conditions. Despite previous work, the locations of oriK and their impact on genome stability remain unclear. We combined 2D gel electrophoresis and whole genome approaches to map genome-wide oriK locations. The DNA copy number profiles of various RNase HI-deficient strains contained multiple peaks, often in consistent locations, identifying candidate oriK sites. Removal of RNase HI protein also leads to global alterations of replication fork migration patterns, often opposite to normal replication directions, and presumably eukaryote-like replication fork merging. Our results have implications for genome stability, offering a new understanding of how RNase HI deficiency results in R-loop-mediated transcription-replication conflict, as well as inappropriate replication stalling or blockage at Ter sites outside of the terminus trap region and at ribosomal operons. © 2013 John Wiley & Sons Ltd.

The Potential for Elimination of Racial-Ethnic Disparities in HIV Treatment Initiation in the Medicaid Population among 14 Southern States

PubMed Central

Zhang, Shun; McGoy, Shanell L.; Dawes, Daniel; Fransua, Mesfin; Rust, George; Satcher, David

2014-01-01

Objectives The purpose of this study was to explore the racial and ethnic disparities in initiation of antiretroviral treatment (ARV treatment or ART) among HIV-infected Medicaid enrollees 18–64 years of age in 14 southern states which have high prevalence of HIV/AIDS and high racial disparities in HIV treatment access and mortality. Methods We used Medicaid claims data from 2005 to 2007 for a retrospective cohort study. We compared frequency variances of HIV treatment uptake among persons of different racial- ethnic groups using univariate and multivariate methods. The unadjusted odds ratio was estimated through multinomial logistic regression. The multinomial logistic regression model was repeated with adjustment for multiple covariates. Results Of the 23,801 Medicaid enrollees who met criteria for initiation of ARV treatment, only one third (34.6%) received ART consistent with national guideline treatment protocols, and 21.5% received some ARV medication, but with sub-optimal treatment profiles. There was no significant difference in the proportion of people who received ARV treatment between black (35.8%) and non-Hispanic whites (35.7%), but Hispanic/Latino persons (26%) were significantly less likely to receive ARV treatment. Conclusions Overall ARV treatment levels for all segments of the population are less than optimal. Among the Medicaid population there are no racial HIV treatment disparities between Black and White persons living with HIV, which suggests the potential relevance of Medicaid to currently uninsured populations, and the potential to achieve similar levels of equality within Medicaid for Hispanic/Latino enrollees and other segments of the Medicaid population. PMID:24769625

Studies of azimuthal dihadron correlations in ultra-central PbPb collisions at $$\\sqrt{s_{NN}} =$$ 2.76 TeV

DOE PAGES

Chatrchyan, Serguei

2014-02-20

Azimuthal dihadron correlations of charged particles have been measured in PbPb collisions atmore » $$\\sqrt{s_{NN}}$$ = 2.76 TeV by the CMS collaboration, using data from the 2011 LHC heavy-ion run. The data set includes a sample of ultra-central (0-0.2% centrality) PbPb events collected using a trigger based on total transverse energy in the hadron forward calorimeters and the total multiplicity of pixel clusters in the silicon pixel tracker. A total of about 1.8 million ultra-central events were recorded, corresponding to an integrated luminosity of 120 inverse microbarns. The observed correlations in ultra-central PbPb events are expected to be particularly sensitive to initial-state fluctuations. The single-particle anisotropy Fourier harmonics, from $$v_2$$ to $$v_6$$, are extracted as a function of particle transverse momentum. At higher transverse momentum, the $$v_2$$ harmonic becomes significantly smaller than the higher-order $$v_n$$ (n greater than or equal to 3). The pt-averaged $$v_2$$ and $$v_3$$ are found to be equal within 2%, while higher-order $$v_n$$ decrease as n increases. The breakdown of factorization of dihadron correlations into single-particle azimuthal anisotropies is observed. This effect is found to be most prominent in the ultra-central PbPb collisions, where the initial-state fluctuations play a dominant role. As a result, a comparison of the factorization data to hydrodynamic predictions with event-by-event fluctuating initial conditions is also presented.« less

Collaborative Procurement Initiative

EPA Pesticide Factsheets

GPP's Clean Energy Collaborative Procurement Initiative provides a platform for deploying clean energy technologies across multiple government and educational organizations for maximum impact on installed solar system capacity and local economic activity.

Initial state with shear in peripheral heavy ion collisions

NASA Astrophysics Data System (ADS)

Magas, V. K.; Gordillo, J.; Strottman, D.; Xie, Y. L.; Csernai, L. P.

2018-06-01

In the present work we propose a new way of constructing the initial state for further hydrodynamic simulation of relativistic heavy ion collisions based on Bjorken-like solution applied streak by streak in the transverse plane. Previous fluid dynamical calculations in Cartesian coordinates with an initial state based on a streak by streak Yang-Mills field led for peripheral higher energy collisions to large angular momentum, initial shear flow and significant local vorticity. Recent experiments verified the existence of this vorticity via the resulting polarization of emitted Λ and Λ ¯ particles. At the same time parton cascade models indicated the existence of more compact initial state configurations, which we are going to simulate in our approach. The proposed model satisfies all the conservation laws, including conservation of a strong initial angular momentum, which is present in noncentral collisions. As a consequence of this large initial angular momentum we observe the rotation of the whole system as well as the fluid shear in the initial state, which leads to large flow vorticity. Another advantage of the proposed model is that the initial state can be given in both [t,x,y,z] and [τ ,x ,y ,η ] coordinates and thus can be tested by all 3+1D hydrodynamical codes which exist in the field.

Strategy Instruction and Maintenance of Basic Multiplication Facts through Digital Game Play

ERIC Educational Resources Information Center

Denham, André R.

2013-01-01

Formative instruction on multiplication primarily focuses on rote memorization. This leads to factual fluency, but also develops a narrow view of multiplication and hinders the development of conceptual understanding. Theory and research recommend the concurrent development of conceptual understanding and factual fluency during the initial stages…

Development of a Climate Resilience Screening Index (CRSI) ...

EPA Pesticide Factsheets

A Climate Resilience Screening Index is being developed that is applicable at multiple scales for the United States. Those scales include national, state, county and community. The index will be applied at the first three scales and at selected communities. The index was developed in order to explicitly include domains, indicators and metrics addressing environmental, economic and societal aspects of climate resilience. In addition, the index uses indicators and metrics that assess ecosystem, economic, governance and social services at these scales. Finally, we are developing forecasting approaches that can relate intended changes in services and governance to likely levels of changes in the resiliency of communities to climate change impacts. The present challenge is the incorporation of the index, its relationships to governance and the developing forecasting tools into Federal decision-making across US government and into state/county/community decision-making across the US. Governmental acceptance of changes to policies often can be just as challenging as the initial technical acceptance of the index and its relation to climate change. Climate Resilience Index is a requested product by ORD AA and EPA Administrator through SHC Program. Index needed to assess states', counties', and communities' abilities of recovery from climate events. Audience: Internal EPA (Administrator, IO, OLEM, OW and OAR) and external (states, counties and communities). Product

Conformational dynamics of a G-protein α subunit is tightly regulated by nucleotide binding.

PubMed

Goricanec, David; Stehle, Ralf; Egloff, Pascal; Grigoriu, Simina; Plückthun, Andreas; Wagner, Gerhard; Hagn, Franz

2016-06-28

Heterotrimeric G proteins play a pivotal role in the signal-transduction pathways initiated by G-protein-coupled receptor (GPCR) activation. Agonist-receptor binding causes GDP-to-GTP exchange and dissociation of the Gα subunit from the heterotrimeric G protein, leading to downstream signaling. Here, we studied the internal mobility of a G-protein α subunit in its apo and nucleotide-bound forms and characterized their dynamical features at multiple time scales using solution NMR, small-angle X-ray scattering, and molecular dynamics simulations. We find that binding of GTP analogs leads to a rigid and closed arrangement of the Gα subdomain, whereas the apo and GDP-bound forms are considerably more open and dynamic. Furthermore, we were able to detect two conformational states of the Gα Ras domain in slow exchange whose populations are regulated by binding to nucleotides and a GPCR. One of these conformational states, the open state, binds to the GPCR; the second conformation, the closed state, shows no interaction with the receptor. Binding to the GPCR stabilizes the open state. This study provides an in-depth analysis of the conformational landscape and the switching function of a G-protein α subunit and the influence of a GPCR in that landscape.

Conformational dynamics of a G-protein α subunit is tightly regulated by nucleotide binding

PubMed Central

Goricanec, David; Stehle, Ralf; Egloff, Pascal; Grigoriu, Simina; Wagner, Gerhard; Hagn, Franz

2016-01-01

Heterotrimeric G proteins play a pivotal role in the signal-transduction pathways initiated by G-protein–coupled receptor (GPCR) activation. Agonist–receptor binding causes GDP-to-GTP exchange and dissociation of the Gα subunit from the heterotrimeric G protein, leading to downstream signaling. Here, we studied the internal mobility of a G-protein α subunit in its apo and nucleotide-bound forms and characterized their dynamical features at multiple time scales using solution NMR, small-angle X-ray scattering, and molecular dynamics simulations. We find that binding of GTP analogs leads to a rigid and closed arrangement of the Gα subdomain, whereas the apo and GDP-bound forms are considerably more open and dynamic. Furthermore, we were able to detect two conformational states of the Gα Ras domain in slow exchange whose populations are regulated by binding to nucleotides and a GPCR. One of these conformational states, the open state, binds to the GPCR; the second conformation, the closed state, shows no interaction with the receptor. Binding to the GPCR stabilizes the open state. This study provides an in-depth analysis of the conformational landscape and the switching function of a G-protein α subunit and the influence of a GPCR in that landscape. PMID:27298341

Multiple polarization states of vector soliton in fiber laser

NASA Astrophysics Data System (ADS)

Chen, Weicheng; Xu, Wencheng; Cao, Hui; Han, Dingan

2007-11-01

Vector soliton is obtained in erbium-doped fiber laser via nonlinear polarization rotation techniques. In experiment, we observe the every 4- and 7-pulse sinusoidal peak modulation. Temporal pulse sinusoidal peak modulation owes to evolution behavior of vector solitons in multiple polarization states. The polarizer in the laser modulates the mode-locked pulses with different polarization states into periodical pulse train intensities modulation. Moreover, the increasing pumping power lead to the appearance of the harmonic pulses and change the equivalent beat length to accelerate the polarization rotation. When the laser cavity length is the n-th multiple ratios to the beat length to maintain the mode-locking, the mode-locked vector soliton is in n-th multiple polarization states, exhibiting every n-pulse sinusoidal peak modulation.

Multiple populations within globular clusters in Early-type galaxies Exploring their effect on stellar initial mass function estimates

NASA Astrophysics Data System (ADS)

Chantereau, W.; Usher, C.; Bastian, N.

2018-05-01

It is now well-established that most (if not all) ancient globular clusters host multiple populations, that are characterised by distinct chemical features such as helium abundance variations along with N-C and Na-O anti-correlations, at fixed [Fe/H]. These very distinct chemical features are similar to what is found in the centres of the massive early-type galaxies and may influence measurements of the global properties of the galaxies. Additionally, recent results have suggested that M/L variations found in the centres of massive early-type galaxies might be due to a bottom-heavy stellar initial mass function. We present an analysis of the effects of globular cluster-like multiple populations on the integrated properties of early-type galaxies. In particular, we focus on spectral features in the integrated optical spectrum and the global mass-to-light ratio that have been used to infer variations in the stellar initial mass function. To achieve this we develop appropriate stellar population synthesis models and take into account, for the first time, an initial-final mass relation which takes into consideration a varying He abundance. We conclude that while the multiple populations may be present in massive early-type galaxies, they are likely not responsible for the observed variations in the mass-to-light ratio and IMF sensitive line strengths. Finally, we estimate the fraction of stars with multiple populations chemistry that come from disrupted globular clusters within massive ellipticals and find that they may explain some of the observed chemical patterns in the centres of these galaxies.

How Kinetics within the Unfolded State Affects Protein Folding: an Analysis Based on Markov State Models and an Ultra-Long MD Trajectory

PubMed Central

Deng, Nan-jie; Dai, Wei

2013-01-01

Understanding how kinetics in the unfolded state affects protein folding is a fundamentally important yet less well-understood issue. Here we employ three different models to analyze the unfolded landscape and folding kinetics of the miniprotein Trp-cage. The first is a 208 μs explicit solvent molecular dynamics (MD) simulation from D. E. Shaw Research containing tens of folding events. The second is a Markov state model (MSM-MD) constructed from the same ultra-long MD simulation; MSM-MD can be used to generate thousands of folding events. The third is a Markov state model built from temperature replica exchange MD simulations in implicit solvent (MSM-REMD). All the models exhibit multiple folding pathways, and there is a good correspondence between the folding pathways from direct MD and those computed from the MSMs. The unfolded populations interconvert rapidly between extended and collapsed conformations on time scales ≤ 40 ns, compared with the folding time of ≈ 5 μs. The folding rates are independent of where the folding is initiated from within the unfolded ensemble. About 90 % of the unfolded states are sampled within the first 40 μs of the ultra-long MD trajectory, which on average explores ~27 % of the unfolded state ensemble between consecutive folding events. We clustered the folding pathways according to structural similarity into “tubes”, and kinetically partitioned the unfolded state into populations that fold along different tubes. From our analysis of the simulations and a simple kinetic model, we find that when the mixing within the unfolded state is comparable to or faster than folding, the folding waiting times for all the folding tubes are similar and the folding kinetics is essentially single exponential despite the presence of heterogeneous folding paths with non-uniform barriers. When the mixing is much slower than folding, different unfolded populations fold independently leading to non-exponential kinetics. A kinetic partition of the Trp-cage unfolded state is constructed which reveals that different unfolded populations have almost the same probability to fold along any of the multiple folding paths. We are investigating whether the results for the kinetics in the unfolded state of the twenty-residue Trp-cage is representative of larger single domain proteins. PMID:23705683

"Bad Luck Mutations": DNA Mutations Are not the Whole Answer to Understanding Cancer Risk.

PubMed

Trosko, James E; Carruba, Giuseppe

2017-01-01

It has been proposed that many human cancers are generated by intrinsic mechanisms that produce "Bad Luck" mutations by the proliferation of organ-specific adult stem cells. There have been serious challenges to this interpretation, including multiple extrinsic factors thought to be correlated with mutations found in cancers associated with these exposures. While support for both interpretations provides some validity, both interpretations ignore several concepts of the multistage, multimechanism process of carcinogenesis, namely, (1) mutations can be generated by both "errors of DNA repair" and "errors of DNA replication," during the "initiation" process of carcinogenesis; (2) "initiated" stem cells must be clonally amplified by nonmutagenic, intrinsic or extrinsic epigenetic mechanisms; (3) organ-specific stem cell numbers can be modified during in utero development, thereby altering the risk to cancer later in life; and (4) epigenetic tumor promoters are characterized by species, individual genetic-, gender-, developmental state-specificities, and threshold levels to be active; sustained and long-term exposures; and exposures in the absence of antioxidant "antipromoters." Because of the inevitability of some of the stem cells generating "initiating" mutations by either "errors of DNA repair" or "errors of DNA replication," a tumor is formed depending on the promotion phase of carcinogenesis. While it is possible to reduce our frequencies of mutagenic "initiated" cells, one can never reduce it to zero. Because of the extended period of the promotion phase of carcinogenesis, strategies to reduce the appearance of cancers must involve the interruption of the promotion of these initiated cells.

Determination of Multiple φ-Torsion Angles in Proteins by Selective and Extensive 13C Labeling and Two-Dimensional Solid-State NMR

NASA Astrophysics Data System (ADS)

Hong, Mei

1999-08-01

We describe an approach to efficiently determine the backbone conformation of solid proteins that utilizes selective and extensive 13C labeling in conjunction with two-dimensional magic-angle-spinning NMR. The selective 13C labeling approach aims to reduce line broadening and other multispin complications encountered in solid-state NMR of uniformly labeled proteins while still enhancing the sensitivity of NMR spectra. It is achieved by using specifically labeled glucose or glycerol as the sole carbon source in the protein expression medium. For amino acids synthesized in the linear part of the biosynthetic pathways, [1-13C]glucose preferentially labels the ends of the side chains, while [2-13C]glycerol labels the Cα of these residues. Amino acids produced from the citric-acid cycle are labeled in a more complex manner. Information on the secondary structure of such a labeled protein was obtained by measuring multiple backbone torsion angles φ simultaneously, using an isotropic-anisotropic 2D correlation technique, the HNCH experiment. Initial experiments for resonance assignment of a selectively 13C labeled protein were performed using 15N-13C 2D correlation spectroscopy. From the time dependence of the 15N-13C dipolar coherence transfer, both intraresidue and interresidue connectivities can be observed, thus yielding partial sequential assignment. We demonstrate the selective 13C labeling and these 2D NMR experiments on a 8.5-kDa model protein, ubiquitin. This isotope-edited NMR approach is expected to facilitate the structure determination of proteins in the solid state.

Addressable single-spin control in multiple quantum dots coupled in series

NASA Astrophysics Data System (ADS)

Nakajima, Takashi

2015-03-01

Electron spin in semiconductor quantum dots (QDs) is promising building block of quantum computers for its controllability and potential scalability. Recent experiments on GaAs QDs have demonstrated necessary ingredients of universal quantum gate operations: single-spin rotations by electron spin resonance (ESR) which is virtually free from the effect of nuclear spin fluctuation, and pulsed control of two-spin entanglement. The scalability of this architecture, however, has remained to be demonstrated in the real world. In this talk, we will present our recent results on implementing single-spin-based qubits in triple, quadruple, and quintuple QDs based on a series coupled architecture defined by gate electrodes. Deterministic initialization of individual spin states and spin-state readout were performed by the pulse operation of detuning between two neighboring QDs. The spin state was coherently manipulated by ESR, where each spin in different QDs is addressed by the shift of the resonance frequency due to the inhomogeneous magnetic field induced by the micro magnet deposited on top of the QDs. Control of two-spin entanglement was also demonstrated. We will discuss key issues for implementing quantum algorithms based on three or more qubits, including the effect of a nuclear spin bath, single-shot readout fidelity, and tuning of multiple qubit devices. Our approaches to these issues will be also presented. This research is supported by Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST) from JSPS, IARPA project ``Multi-Qubit Coherent Operations'' through Copenhagen University, and Grant-in-Aid for Scientific Research from JSPS.

HIV community viral load trends in South Carolina.

PubMed

Chakraborty, Hrishikesh; Weissman, Sharon; Duffus, Wayne A; Hossain, Akhtar; Varma Samantapudi, Ashok; Iyer, Medha; Albrecht, Helmut

2017-03-01

Community viral load is an aggregate measure of HIV viral load in a particular geographic location, community, or subgroup. Community viral load provides a measure of disease burden in a community and community transmission risk. This study aims to examine community viral load trend in South Carolina and identify differences in community viral load trends between selected population subgroups using a state-wide surveillance dataset that maintains electronic records of all HIV viral load measurements reported to the state health department. Community viral load trends were examined using random mixed effects models, adjusting for age, race, gender, residence, CD4 counts, HIV risk group, and initial antiretroviral regimen during the study period, and time. The community viral load gradually decreased from 2004 to 2013 ( p < 0.0001). The number of new infections also decreased ( p = 0.0001) over time. A faster rate of decrease was seen among men compared to women ( p < 0.0001), men who have sex with men ( p = 0.0001) compared to heterosexuals, patients diagnosed in urban areas compared to that in rural areas ( p = 0.0004), and patients prescribed single-tablet regimen compared to multiple-tablet regimen ( p < 0.0001). While the state-wide community viral load decreased over time, the decline was not uniform among residence at diagnosis, HIV risk group, and single-tablet regimen versus multiple-tablet regimen subgroups. Slower declines in community viral load among females, those in rural areas, and heterosexuals suggest possible disparities in care that require further exploration. The association between using single-tablet regimen and faster community viral load decline is noteworthy.

Framing Innovation: The Impact of the Superintendent's Technology Infrastructure Decisions on the Acceptance of Large-Scale Technology Initiatives

ERIC Educational Resources Information Center

Arnold, Erik P.

2014-01-01

A multiple-case qualitative study of five school districts that had implemented various large-scale technology initiatives was conducted to describe what superintendents do to gain acceptance of those initiatives. The large-scale technology initiatives in the five participating districts included 1:1 District-Provided Device laptop and tablet…

Structural Transition and Antibody Binding of EBOV GP and ZIKV E Proteins from Pre-Fusion to Fusion-Initiation State.

PubMed

Lappala, Anna; Nishima, Wataru; Miner, Jacob; Fenimore, Paul; Fischer, Will; Hraber, Peter; Zhang, Ming; McMahon, Benjamin; Tung, Chang-Shung

2018-05-10

Membrane fusion proteins are responsible for viral entry into host cells—a crucial first step in viral infection. These proteins undergo large conformational changes from pre-fusion to fusion-initiation structures, and, despite differences in viral genomes and disease etiology, many fusion proteins are arranged as trimers. Structural information for both pre-fusion and fusion-initiation states is critical for understanding virus neutralization by the host immune system. In the case of Ebola virus glycoprotein (EBOV GP) and Zika virus envelope protein (ZIKV E), pre-fusion state structures have been identified experimentally, but only partial structures of fusion-initiation states have been described. While the fusion-initiation structure is in an energetically unfavorable state that is difficult to solve experimentally, the existing structural information combined with computational approaches enabled the modeling of fusion-initiation state structures of both proteins. These structural models provide an improved understanding of four different neutralizing antibodies in the prevention of viral host entry.

Depersonalisation and schizophrenia: Comparative study of initial and multiple episodes of schizophrenia.

PubMed

Luque-Luque, Rogelio; Chauca-Chauca, Geli Marie; Alonso-Lobato, Pablo; Jaen-Moreno, M Jose

2016-01-01

The phenomena of depersonalisation/derealisation have classically been associated with the initial phases of psychosis, and it is assumed that they would precede (even by years) the onset of clinical psychosis, being much more common in the prodromal and acute phases of the illness. The aims of the present study are to analyse the differences in depersonalisation/derealisation between patients with initial and multiple episodes and the factors that could influence this. A descriptive, controlled and cross-sectional study of 48 patients diagnosed with paranoid schizophrenia (20 with an initial episode and 28 with multiple episodes). These patients were assessed using scales such as the Cambridge Depersonalization Scale, the Positive and Negative Symptom Scale, and the Dissociative Experiences Scale. Participants with initial episodes score higher on both the Cambridge Depersonalisation Scale, and the subscale of the Dissociative Experiences Scale that evaluates such experiences. There were no associations between these types of experience and the positive symptoms subscale of the Positive and Negative Symptom Scale. Depersonalisation/derealisation experiences appear with greater frequency, duration and intensity in patients in the early stages of the illnesses, gradually decreasing as they become chronic. Copyright © 2016 SEP y SEPB. Published by Elsevier España. All rights reserved.

Stochastic switching of TiO2-based memristive devices with identical initial memory states

PubMed Central

2014-01-01

In this work, we show that identical TiO2-based memristive devices that possess the same initial resistive states are only phenomenologically similar as their internal structures may vary significantly, which could render quite dissimilar switching dynamics. We experimentally demonstrated that the resistive switching of practical devices with similar initial states could occur at different programming stimuli cycles. We argue that similar memory states can be transcribed via numerous distinct active core states through the dissimilar reduced TiO2-x filamentary distributions. Our hypothesis was finally verified via simulated results of the memory state evolution, by taking into account dissimilar initial filamentary distribution. PMID:24994953

A Descriptive Analysis of State-Supported Formative Assessment Initiatives in New York and Vermont. Summary. Issues & Answers. REL 2012-No. 112

ERIC Educational Resources Information Center

Louie, Josephine; Sanchez, Maria Teresa; North, Charlotte; Cazabon, Mary; Melo, Daniel; Kagle, Melissa

2011-01-01

This study examines two state-supported formative assessment initiatives that promote a consensus definition of formative assessment endorsed by the Council of Chief State School Officers. It describes the primary components of the two initiatives and the strategies that state, district, and school leaders report using to support implementation of…

A Descriptive Analysis of State-Supported Formative Assessment Initiatives in New York and Vermont. Issues & Answers. REL 2012-No. 112

ERIC Educational Resources Information Center

Louie, Josephine; Sanchez, Maria Teresa; North, Charlotte; Cazabon, Mary; Melo, Daniel; Kagle, Melissa

2011-01-01

This study examines two state-supported formative assessment initiatives that promote a consensus definition of formative assessment endorsed by the Council of Chief State School Officers. It describes the primary components of the two initiatives and the strategies that state, district, and school leaders report using to support implementation of…

Family Support: Fostering Leadership and Partnership to Improve Access and Quality. Building State Early Childhood Comprehensive Systems Series, Number 14

ERIC Educational Resources Information Center

Thompson, Lisa; Uyeda, Kimberly

2004-01-01

The federal Maternal and Child Health Bureau (MCHB) has launched a five-year initiative that will support state efforts to build comprehensive early childhood service systems. This initiative--the State Early Childhood Comprehensive Systems (SECCS) Initiative--provides planning and implementation grants to the state and territory Maternal and…

Sudden birth versus sudden death of entanglement for the extended Werner-like state in a dissipative environment

NASA Astrophysics Data System (ADS)

Shan, Chuan-Jia; Chen, Tao; Liu, Ji-Bing; Cheng, Wei-Wen; Liu, Tang-Kun; Huang, Yan-Xia; Li, Hong

2010-06-01

In this paper, we investigate the dynamical behaviour of entanglement in terms of concurrence in a bipartite system subjected to an external magnetic field under the action of dissipative environments in the extended Werner-like initial state. The interesting phenomenon of entanglement sudden death as well as sudden birth appears during the evolution process. We analyse in detail the effect of the purity of the initial entangled state of two qubits via Heisenberg XY interaction on the apparition time of entanglement sudden death and entanglement sudden birth. Furthermore, the conditions on the conversion of entanglement sudden death and entanglement sudden birth can be generalized when the initial entangled state is not pure. In particular, a critical purity of the initial mixed entangled state exists, above which entanglement sudden birth vanishes while entanglement sudden death appears. It is also noticed that stable entanglement, which is independent of different initial states of the qubits (pure or mixed state), occurs even in the presence of decoherence. These results arising from the combination of the extended Werner-like initial state and dissipative environments suggest an approach to control and enhance the entanglement even after purity induced sudden birth, death and revival.

A practical theoretical formalism for atomic multielectron processes: direct multiple ionization by a single auger decay or by impact of a single electron or photon

NASA Astrophysics Data System (ADS)

Liu, Pengfei; Zeng, Jiaolong; Yuan, Jianmin

2018-04-01

Multiple electron processes occur widely in atoms, molecules, clusters, and condensed matters when they are interacting with energetic particles or intense laser fields. Direct multielectron processes (DMEP) are the most complicated among the general multiple electron processes and are the most difficult to describe theoretically. In this work, a unified and accurate theoretical formalism is proposed on the DMEP of atoms including the multiple auger decay and multiple ionization by an impact of a single electron or a single photon based on the atomic collision theory described by a correlated many-body Green's function. Such a practical treatment is made possible by taking consideration of the different coherence features of the atoms (matter waves) in the initial and final states. We first explain how the coherence characteristics of the ejected continuum electrons is largely destructed, by taking the electron impact direct double ionization process as an example. The direct double ionization process is completely different from the single ionization where the complete interference can be maintained. The detailed expressions are obtained for the energy correlations among the continuum electrons and energy resolved differential and integral cross sections according to the separation of knock-out (KO) and shake-off (SO) mechanisms for the electron impact direct double ionization, direct double and triple auger decay, and double and triple photoionization (TPI) processes. Extension to higher order DMEP than triple ionization is straight forward by adding contributions of the following KO and SO processes. The approach is applied to investigate the electron impact double ionization processes of C+, N+, and O+, the direct double and triple auger decay of the K-shell excited states of C+ 1s2{s}22{p}2{}2D and {}2P, and the double and TPI of lithium. Comparisons with the experimental and other theoretical investigations wherever available in the literature show that our theoretical formalism is accurate and effective in treating the atomic multielectron processes.

Characteristics of first suicide attempts in single versus multiple suicide attempters with bipolar disorder.

PubMed

Michaelis, Benjamin H; Goldberg, Joseph F; Singer, Tara M; Garno, Jessica L; Ernst, Carrie L; Davis, Glen P

2003-01-01

Although suicidality remains highly prevalent among patients with bipolar disorder, little research exists examining the characteristics of successive attempts among individuals who make and survive a first suicide attempt. We compared bipolar subjects with a history of one suicide attempt to those with multiple attempts and assessed demographic characteristics, family histories, psychopathology, and clinical dimensions of suicidal behavior. Fifty-two DSM-IV bipolar patients (age 21 to 74 years) with a history of at least one suicide attempt were consecutively evaluated in the Bipolar Disorders Research Clinic of the New York Presbyterian Hospital. Circumstances surrounding each lifetime suicide attempt were assessed by direct interviews, questionnaires, and chart reviews along with family psychiatric histories, substance abuse histories, current psychopathology, and features of impulsivity and aggression. Multiple suicide attempts occurred in approximately two thirds of the study group. Single attempters were significantly more likely than multiple attempters to show high seriousness of intent at their first attempt (OR = 0.65, 95% CI = 0.43 to 0.99), and tended to be less likely than multiple attempters to exhibit mixed states at their first attempt (OR = 0.54, 95% CI = 0.28 to 1.01). Seriousness of intent was consistent across the first and second attempts (r =.48, P <.01) and second and third attempts (r =.74, P <.05). Single and multiple attempters differed in no other clinical or demographic characteristics studied. We conclude that multiple suicide attempts are common among bipolar patients. Those who survive an initial suicide attempt involving high seriousness of intent appear less likely than those with low intent to make subsequent attempts. Consequently, single attempters may represent a group more closely resembling those who complete suicide on a first attempt, in terms of the risk for death associated with their first attempt. However, multiple suicide attempts among bipolar patients are not necessarily associated with a higher risk for lethality in first suicide attempt survivors. Copyright 2003, Elsevier Science (USA). All rights reserved.

Limited common origins of multiple adult health-related behaviors: Evidence from U.S. twins.

PubMed

Sudharsanan, Nikkil; Behrman, Jere R; Kohler, Hans-Peter

2016-12-01

Health-related behaviors are significant contributors to morbidity and mortality in the United States, yet evidence on the underlying causes of the vast within-population variation in behaviors is mixed. While many potential causes of health-related behaviors have been identified-such as schooling, genetics, and environments-little is known on how much of the variation across multiple behaviors is due to a common set of causes. We use three separate datasets on U.S. twins to investigate the degree to which multiple health-related behaviors correlate and can be explained by a common set of factors. We find that aside from smoking and drinking, most behaviors are not strongly correlated among individuals. Based on the results of both within-identical-twins regressions and multivariate behavioral genetics models, we find some evidence that schooling may be related to smoking but not to the covariation between multiple behaviors. Similarly, we find that a large fraction of the variance in each of the behaviors is consistent with genetic factors; however, we do not find strong evidence that a single common set of genes explains variation in multiple behaviors. We find, however, that a large portion of the correlation between smoking and heavy drinking is consistent with common, mostly childhood, environments. This suggests that the initiation and patterns of these two behaviors might arise from a common childhood origin. Research and policy to identify and modify this source may provide a strong way to reduce the population health burden of smoking and heavy drinking. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analysis of Wind Characteristics at United States Tall Tower Measurement Sites

NASA Astrophysics Data System (ADS)

Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.

2008-12-01

A major initiative of the U.S. Department of Energy (DOE) is to ensure that 20% of the country's electricity is produced by wind energy by the year 2030. An understanding of the boundary layer characteristics, especially at elevated heights greater than 80 meters (m) above the surface is a key factor for wind turbine design, wind plant layout, and identifying potential markets for advanced wind technology. The wind resource group at the DOE National Renewable Energy Laboratory is analyzing wind data collected at tall (80+ m) towers across the United States. The towers established by both public and private initiative, measure wind characteristics at multiple levels above the surface, with the highest measurement levels generally between 80 and 110 m. A few locations have measurements above 200 m. Measurements of wind characteristics over a wide range of heights are useful to: (1) characterize the local and regional wind climate; (2) validate wind resource estimates derived from numerical models; and (3) directly assess and analyze specific wind resource characteristics such as wind speed shear over the turbine blade swept area. The majority of the available public tall tower measurement sites are located between the Appalachian and Rocky Mountains. The towers are not evenly distributed among the states. The states with the largest number of towers include Indiana, Iowa, Missouri, and Kansas. These states have five or six towers collecting data. Other states with multiple tower locations include Texas, Oklahoma, Minnesota, and Ohio. The primary consideration when analyzing the data from the tall towers is identifying tower flow effects that not only can produce slightly misleading average wind speeds, but also significantly misleading wind speed shear values. In addition, the periods-of-record of most tall tower data are only one to two years in length. The short data collection time frame does not significantly affect the diurnal wind speed pattern though it does complicate analysis of seasonal wind patterns. The tall tower data analysis revealed some distinct regional features of wind shear climatology. For example, the wind shear exponent (alpha) at the towers in the Central Plains is generally between 0.15 and 0.25, greater than the commonly used 1/7 power law exponent value of 0.143. Another characteristic of Central Plains wind climatology was that winds from the south had alpha values of 0.2 to 0.3, while northerly winds had lower alpha values from 0.1 to 0.2. The wind resource at a particular tower is affected not only by the regional climatology but also by local conditions such as terrain, surface roughness, and structure of the lower boundary layer.

The Contribution of Soil Moisture Information to Forecast Skill: Two Studies

NASA Technical Reports Server (NTRS)

Koster, Randal

2010-01-01

This talk briefly describes two recent studies on the impact of soil moisture information on hydrological and meteorological prediction. While the studies utilize soil moisture derived from the integration of large-scale land surface models with observations-based meteorological data, the results directly illustrate the potential usefulness of satellite-derived soil moisture information (e.g., from SMOS and SMAP) for applications in prediction. The first study, the GEWEX- and ClIVAR-sponsored GLACE-2 project, quantifies the contribution of realistic soil moisture initialization to skill in subseasonal forecasts of precipitation and air temperature (out to two months). The multi-model study shows that soil moisture information does indeed contribute skill to the forecasts, particularly for air temperature, and particularly when the initial local soil moisture anomaly is large. Furthermore, the skill contributions tend to be larger where the soil moisture initialization is more accurate, as measured by the density of the observational network contributing to the initialization. The second study focuses on streamflow prediction. The relative contributions of snow and soil moisture initialization to skill in streamflow prediction at seasonal lead, in the absence of knowledge of meteorological anomalies during the forecast period, were quantified with several land surface models using uniquely designed numerical experiments and naturalized streamflow data covering mUltiple decades over the western United States. In several basins, accurate soil moisture initialization is found to contribute significant levels of predictive skill. Depending on the date of forecast issue, the contributions can be significant out to leads of six months. Both studies suggest that improvements in soil moisture initialization would lead to increases in predictive skill. The relevance of SMOS and SMAP satellite-based soil moisture information to prediction are discussed in the context of these studies.