A New Approach to Predict Microbial Community Assembly and Function Using a Stochastic, Genome-Enabled Modeling Framework

NASA Astrophysics Data System (ADS)

King, E.; Brodie, E.; Anantharaman, K.; Karaoz, U.; Bouskill, N.; Banfield, J. F.; Steefel, C. I.; Molins, S.

2016-12-01

Characterizing and predicting the microbial and chemical compositions of subsurface aquatic systems necessitates an understanding of the metabolism and physiology of organisms that are often uncultured or studied under conditions not relevant for one's environment of interest. Cultivation-independent approaches are therefore important and have greatly enhanced our ability to characterize functional microbial diversity. The capability to reconstruct genomes representing thousands of populations from microbial communities using metagenomic techniques provides a foundation for development of predictive models for community structure and function. Here, we discuss a genome-informed stochastic trait-based model incorporated into a reactive transport framework to represent the activities of coupled guilds of hypothetical microorganisms. Metabolic pathways for each microbe within a functional guild are parameterized from metagenomic data with a unique combination of traits governing organism fitness under dynamic environmental conditions. We simulate the thermodynamics of coupled electron donor and acceptor reactions to predict the energy available for cellular maintenance, respiration, biomass development, and enzyme production. While `omics analyses can now characterize the metabolic potential of microbial communities, it is functionally redundant as well as computationally prohibitive to explicitly include the thousands of recovered organisms into biogeochemical models. However, one can derive potential metabolic pathways from genomes along with trait-linkages to build probability distributions of traits. These distributions are used to assemble groups of microbes that couple one or more of these pathways. From the initial ensemble of microbes, only a subset will persist based on the interaction of their physiological and metabolic traits with environmental conditions, competing organisms, etc. Here, we analyze the predicted niches of these hypothetical microbes and assess the ability of a stochastically assembled community of organisms to predict subsurface biogeochemical dynamics.

Dual Trajectories of Reactive and Proactive Aggression from Mid-childhood to Early Adolescence: Relations to Sensation Seeking, Risk Taking, and Moral Reasoning.

PubMed

Cui, Lixian; Colasante, Tyler; Malti, Tina; Ribeaud, Denis; Eisner, Manuel P

2016-05-01

We examined the roles of sensation seeking, risk taking, and moral reasoning in the development of reactive and proactive aggression. Data were drawn from a multiethnic, longitudinal study of children from Switzerland (N = 1571; 52 % male; assessed annually over 6 years; 7-years-old at Time 1). At all 6 time points, teachers reported children's reactive and proactive aggression via questionnaire. Children's sensation seeking (at Time 1) and risk taking (at Time 2) were assessed with two interactive computer tasks and their moral reasoning was assessed at Time 2 in response to four hypothetical vignettes depicting moral transgressions. Parallel process Latent Class Growth Analysis (PP-LCGA) identified six dual trajectories of reactive and proactive aggression. Children with either childhood-limited or adolescent-onset aggression showed high sensation seeking. Children with persistent, high levels of both reactive and proactive aggression across time showed high levels of sensation seeking and risk taking, as well as low levels of moral reasoning. Children with only high risk taking were more likely to display moderate levels of aggression across time. These findings highlight the shared and differential roles of sensation seeking, risk taking, and moral reasoning in the dual development of reactive and proactive aggression from mid-childhood to early adolescence. We discuss implications for common and tailored strategies to combat these aggression subtypes.

Impact of layer thickness and well orientation on caprock integrity for geologic carbon storage

DOE PAGES

Newell, P.; Martinez, M. J.; Eichhubl, P.

2016-07-29

Economic feasibility of geologic carbon storage demands sustaining large storage rates without damaging caprock seals. Reactivation of pre-existing or newly formed fractures may provide a leakage pathway across caprock layers. In this paper, we apply an equivalent continuum approach within a finite element framework to model the fluid-pressure-induced reactivation of pre-existing fractures within the caprock, during high-rate injection of super-critical CO 2 into a brine-saturated reservoir in a hypothetical system, using realistic geomechanical and fluid properties. We investigate the impact of reservoir to caprock layer thickness, wellbore orientation, and injection rate on overall performance of the system with respect tomore » caprock failure and leakage. We find that vertical wells result in locally higher reservoir pressures relative to horizontal injection wells for the same injection rate, with high pressure inducing caprock leakage along reactivated opening-mode fractures in the caprock. After prolonged injection, leakage along reactivated fractures in the caprock is always higher for vertical than horizontal injection wells. Furthermore, we find that low ratios of reservoir to caprock thickness favor high excess pressure and thus fracture reactivation in the caprock. Finally, injection into thick reservoir units thus lowers the risk associated with CO 2 leakage.« less

Characterization of Impact Initiation of Aluminum-Based Intermetallic-Forming Reactive Materials

DTIC Science & Technology

2011-12-01

compressed intermetallic-forming aluminum-based reactive materials upon impact initiation, consisting of equi-volumetric tantalum-aluminum, tungsten-aluminum...18 2.3.4 Dynamic Energy Release Characterization using Pig Test . . . . . . 21 2.3.5 Shock Compression of Reactive Powder Mixtures...is to evaluate the reaction initiation characteristics of quasi-statically compressed intermetallic-forming aluminum-based reactive materials upon

Age Differences in Affective and Cardiovascular Responses to a Negative Social Interaction: The Role of Goals, Appraisals, and Emotion Regulation

PubMed Central

Luong, Gloria; Charles, Susan T.

2014-01-01

Older adults often report less affective reactivity to interpersonal tensions than younger individuals, but few studies have directly investigated mechanisms explaining this effect. The current study examined whether older adults’ differential endorsement of goals, appraisals, and emotion regulation strategies (i.e., conflict avoidance/de-escalation, self-distraction) during a controlled negative social interaction may explain age differences in affective and cardiovascular responses to the conflict discussion. Participants (N=159; 80 younger adults, 79 older adults) discussed hypothetical dilemmas with disagreeable confederates. Throughout the laboratory session, participants’ subjective emotional experience, blood pressure, and pulse rate were assessed. Older adults generally exhibited less reactivity (negative affect reactivity, diastolic blood pressure reactivity, and pulse rate reactivity) to the task, and more pronounced positive and negative affect recovery following the task, than did younger adults. Older adults appraised the task as more enjoyable and the confederate as more likeable, and more strongly endorsed goals to perform well on the task, which mediated age differences in negative affect reactivity, pulse rate reactivity, and positive affect recovery (i.e., increases in post-task positive affect), respectively. In addition, younger adults showed increased negative affect reactivity with greater use of self-distraction, whereas older adults did not. Together, findings suggest that older adults respond less negatively to unpleasant social interactions than younger adults, and these responses are explained in part by older adults’ pursuit of different motivational goals, less threatening appraisals of the social interaction, and more effective use of self-distraction, compared to younger adults. PMID:24773101

Probabilistic Asteroid Impact Risk Assessment for the Hypothetical PDC17 Impact Exercise

NASA Technical Reports Server (NTRS)

Wheeler, Lorien; Mathias, Donovan

2017-01-01

Performing impact risk assessment for the 2017 Planetary Defense Conference (PDC17) hypothetical impact exercise, to take place at the PDC17 conference, May 15-20, 2017. Impact scenarios and trajectories are developed and provided by NASA's Near Earth Objects Office at JPL (Paul Chodas). These results represent purely hypothetical impact scenarios, and do not reflect any known asteroid threat. Risk assessment was performed using the Probabilistic Asteroid Impact Risk (PAIR) model developed by the Asteroid Threat Assessment Project (ATAP) at NASA Ames Research Center. This presentation includes sample results that may be presented or used in discussions during the various stages of the impact exercisecenter dot Some cases represent alternate scenario options that may not be used during the actual impact exercise at the PDC17 conference. Updates to these initial assessments and/or additional scenario assessments may be performed throughout the impact exercise as different scenario options unfold.

Detection of functionally important regions in "hypothetical proteins" of known structure.

PubMed

Nimrod, Guy; Schushan, Maya; Steinberg, David M; Ben-Tal, Nir

2008-12-10

Structural genomics initiatives provide ample structures of "hypothetical proteins" (i.e., proteins of unknown function) at an ever increasing rate. However, without function annotation, this structural goldmine is of little use to biologists who are interested in particular molecular systems. To this end, we used (an improved version of) the PatchFinder algorithm for the detection of functional regions on the protein surface, which could mediate its interactions with, e.g., substrates, ligands, and other proteins. Examination, using a data set of annotated proteins, showed that PatchFinder outperforms similar methods. We collected 757 structures of hypothetical proteins and their predicted functional regions in the N-Func database. Inspection of several of these regions demonstrated that they are useful for function prediction. For example, we suggested an interprotein interface and a putative nucleotide-binding site. A web-server implementation of PatchFinder and the N-Func database are available at http://patchfinder.tau.ac.il/.

The economics of improving medication adherence in osteoporosis: validation and application of a simulation model.

PubMed

Patrick, Amanda R; Schousboe, John T; Losina, Elena; Solomon, Daniel H

2011-09-01

Adherence to osteoporosis treatment is low. Although new therapies and behavioral interventions may improve medication adherence, questions are likely to arise regarding their cost-effectiveness. Our objectives were to develop and validate a model to simulate the clinical outcomes and costs arising from various osteoporosis medication adherence patterns among women initiating bisphosphonate treatment and to estimate the cost-effectiveness of a hypothetical intervention to improve medication adherence. We constructed a computer simulation using estimates of fracture rates, bisphosphonate treatment effects, costs, and utilities for health states drawn from the published literature. Probabilities of transitioning on and off treatment were estimated from administrative claims data. Patients were women initiating bisphosphonate therapy from the general community. We evaluated a hypothetical behavioral intervention to improve medication adherence. Changes in 10-yr fracture rates and incremental cost-effectiveness ratios were evaluated. A hypothetical intervention with a one-time cost of $250 and reducing bisphosphonate discontinuation by 30% had an incremental cost-effectiveness ratio (ICER) of $29,571 per quality-adjusted life year in 65-yr-old women initiating bisphosphonates. Although the ICER depended on patient age, intervention effectiveness, and intervention cost, the ICERs were less than $50,000 per quality-adjusted life year for the majority of intervention cost and effectiveness scenarios evaluated. Results were sensitive to bisphosphonate cost and effectiveness and assumptions about the rate at which intervention and treatment effects decline over time. Our results suggests that behavioral interventions to improve osteoporosis medication adherence will likely have favorable ICERs if their efficacy can be sustained.

Freeze-quench (57)Fe-Mössbauer spectroscopy: trapping reactive intermediates.

PubMed

Krebs, Carsten; Bollinger, J Martin

2009-01-01

(57)Fe-Mössbauer spectroscopy is a method that probes transitions between the nuclear ground state (I=1/2) and the first nuclear excited state (I=3/2). This technique provides detailed information about the chemical environment and electronic structure of iron. Therefore, it has played an important role in studies of the numerous iron-containing proteins and enzymes. In conjunction with the freeze-quench method, (57)Fe-Mössbauer spectroscopy allows for monitoring changes of the iron site(s) during a biochemical reaction. This approach is particularly powerful for detection and characterization of reactive intermediates. Comparison of experimentally determined Mössbauer parameters to those predicted by density functional theory for hypothetical model structures can then provide detailed insight into the structures of reactive intermediates. We have recently used this methodology to study the reactions of various mononuclear non-heme-iron enzymes by trapping and characterizing several Fe(IV)-oxo reaction intermediates. In this article, we summarize these findings and demonstrate the potential of the method. © Springer Science+Business Media B.V. 2009

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

Scott Stewart, D., E-mail: dss@illinois.edu; Hernández, Alberto; Lee, Kibaek

The estimation of pressure and temperature histories, which are required to understand chemical pathways in condensed phase explosives during detonation, is discussed. We argue that estimates made from continuum models, calibrated by macroscopic experiments, are essential to inform modern, atomistic-based reactive chemistry simulations at detonation pressures and temperatures. We present easy to implement methods for general equation of state and arbitrarily complex chemical reaction schemes that can be used to compute reactive flow histories for the constant volume, the energy process, and the expansion process on the Rayleigh line of a steady Chapman-Jouguet detonation. A brief review of state-of-the-art ofmore » two-component reactive flow models is given that highlights the Ignition and Growth model of Lee and Tarver [Phys. Fluids 23, 2362 (1980)] and the Wide-Ranging Equation of State model of Wescott, Stewart, and Davis [J. Appl. Phys. 98, 053514 (2005)]. We discuss evidence from experiments and reactive molecular dynamic simulations that motivate models that have several components, instead of the two that have traditionally been used to describe the results of macroscopic detonation experiments. We present simplified examples of a formulation for a hypothetical explosive that uses simple (ideal) equation of state forms and detailed comparisons. Then, we estimate pathways computed from two-component models of real explosive materials that have been calibrated with macroscopic experiments.« less

Effects of Social Stressors on Cardiovascular Reactivity in Black and White Women

PubMed Central

Lepore, Stephen J.; Revenson, Tracey A.; Weinberger, Sarah L.; Weston, Peter; Frisina, Pasquale G.; Robertson, Rommel; Portillo, Minerva Mentor; Jones, Hollie; Cross, William

2008-01-01

Background Behavioral scientists have theorized that perceived racism in social interactions may account for some of the observed disparities in coronary heart disease between Black and White Americans. Purpose The objective was to examine whether racial stress influences cardiovascular reactivity, a risk factor for cardiovascular disease. Methods We measured cardiovascular responses in Black and White women (n = 80) as they talked about 3 hypothetical scenarios: (a) being accused of shoplifting (racial stressor), (b) experiencing airport delays (nonracial stressor), and (c) giving a campus tour (control). Results Relative to White women, Black women had significantly greater mean diastolic blood pressure reactivity (3.81 vs. 0.25 mmHg; p < .05) in response to the racial stressor than in response to the nonracial stressor. Black women exhibited significantly lower heart rate during recovery following the racial stressor than during recovery following the nonracial stressor (−0.37 beats/min vs. 0.86 beats/min; p < .001). Among Black women, those who explicitly made race attributions during the racial stressor had greater systolic but not diastolic blood pressure reactivity than those who did not make racial attributions (8.32 mmHg vs. 2.17 mmHg; p < .05). Conclusions These findings suggest that perceived racism in social interactions may contribute to increased physiological stress for Black women. PMID:16542126

Hypothetical Modeling of Redox Conditions Within a Complex Ground-Water Flow Field in a Glacial Setting

USGS Publications Warehouse

Feinstein, Daniel T.; Thomas, Mary Ann

2009-01-01

This report describes a modeling approach for studying how redox conditions evolve under the influence of a complex ground-water flow field. The distribution of redox conditions within a flow system is of interest because of the intrinsic susceptibility of an aquifer to redox-sensitive, naturally occurring contaminants - such as arsenic - as well as anthropogenic contaminants - such as chlorinated solvents. The MODFLOW-MT3D-RT3D suite of code was applied to a glacial valley-fill aquifer to demonstrate a method for testing the interaction of flow patterns, sources of reactive organic carbon, and availability of electron acceptors in controlling redox conditions. Modeling results show how three hypothetical distributions of organic carbon influence the development of redox conditions in a water-supply aquifer. The distribution of strongly reduced water depends on the balance between the rate of redox reactions and the capability of different parts of the flow system to transmit oxygenated water. The method can take account of changes in the flow system induced by pumping that result in a new distribution of reduced water.

Changes in skin reactivity and associated factors in patients sensitized to house dust mites after 1 year of allergen-specific immunotherapy.

PubMed

Son, Jeong-Yeop; Jung, Mann-Hong; Koh, Kwang-Wook; Park, Eun-Kee; Heo, Jeong-Hoon; Choi, Gil-Soon; Kim, Hee-Kyoo

2017-04-01

Allergen-specific immunotherapy (SIT) can significantly improve symptoms and reduce the need for symptomatic medication. The aim of this study was to investigate changes in skin reactivity to house dust mites (HDMs) as an immunologic response and associated factors after 1 year of immunotherapy. A total of 80 patients with allergic airway diseases who received subcutaneous SIT with HDMs from 2009 to 2014 were evaluated. The investigated parameters were basic demographic characteristics, skin reactivity and specific IgE for HDM, serum total IgE level, blood eosinophil counts, and medication score. The mean levels of skin reactivity to HDMs, blood eosinophil counts, and medication scores after 1 year were significantly reduced from baseline. In univariate comparison of the changes in skin reactivity to HDMs, age ≤30 years, HDMs only as target of immunotherapy, and high initial skin reactivity (≥2) to HDMs were significantly associated with the reduction in skin test reactivity. In multivariate analysis, high initial skin reactivity and HDMs only as target allergens were significantly associated with changes in skin reactivity to HDMs. In the receiver operating characteristic curve of the initial mean skin reactivity to HDMs for more than 50% reduction, the optimal cutoff value was 2.14. This study showed significant reductions in allergen skin reactivity to HDMs after 1 year of immunotherapy in patients sensitized to HDMs. The extent of initial allergen skin reactivity and only HDMs as target allergen were important predictive factors for changes in skin reactivity.

Observing system simulation experiments with multiple methods

NASA Astrophysics Data System (ADS)

Ishibashi, Toshiyuki

2014-11-01

An observing System Simulation Experiment (OSSE) is a method to evaluate impacts of hypothetical observing systems on analysis and forecast accuracy in numerical weather prediction (NWP) systems. Since OSSE requires simulations of hypothetical observations, uncertainty of OSSE results is generally larger than that of observing system experiments (OSEs). To reduce such uncertainty, OSSEs for existing observing systems are often carried out as calibration of the OSSE system. The purpose of this study is to achieve reliable OSSE results based on results of OSSEs with multiple methods. There are three types of OSSE methods. The first one is the sensitivity observing system experiment (SOSE) based OSSE (SOSEOSSE). The second one is the ensemble of data assimilation cycles (ENDA) based OSSE (ENDA-OSSE). The third one is the nature-run (NR) based OSSE (NR-OSSE). These three OSSE methods have very different properties. The NROSSE evaluates hypothetical observations in a virtual (hypothetical) world, NR. The ENDA-OSSE is very simple method but has a sampling error problem due to a small size ensemble. The SOSE-OSSE requires a very highly accurate analysis field as a pseudo truth of the real atmosphere. We construct these three types of OSSE methods in the Japan meteorological Agency (JMA) global 4D-Var experimental system. In the conference, we will present initial results of these OSSE systems and their comparisons.

Communicating Uncertain Experimental Evidence

ERIC Educational Resources Information Center

Davis, Alexander L.; Fischhoff, Baruch

2014-01-01

Four experiments examined when laypeople attribute unexpected experimental outcomes to error, in foresight and in hindsight, along with their judgments of whether the data should be published. Participants read vignettes describing hypothetical experiments, along with the result of the initial observation, considered as either a possibility…

Potential impact of reactive vaccination in controlling cholera outbreaks: an exploratory analysis using a Zimbabwean experience.

PubMed

Kim, Sun-Young; Choi, Yeongchull; Mason, Peter R; Rusakaniko, Simbarashe; Goldie, Sue J

2011-09-05

To contain ongoing cholera outbreaks, the World Health Organization has suggested that reactive vaccination should be considered in addition to its previous control measures. To explore the potential impact of a hypothetical reactive oral cholera vaccination using the example of the recent large-scale cholera outbreak in Zimbabwe. This was a retrospective cost-effectiveness analysis calculating the health and economic burden of the cholera outbreak in Zimbabwe with and without reactive vaccination. The primary outcome measure was incremental cost per disability-adjusted life year (DALY) averted. Under the base-case assumptions (assuming 50% coverage among individuals aged ≥2 years), reactive vaccination could have averted 1 320 deaths and 23 650 DALYs. Considering herd immunity, the corresponding values would have been 2 920 deaths and 52 360 DALYs averted. The total vaccination costs would have been ~$74 million and ~$21 million, respectively, with per-dose vaccine price of US$5 and $1. The incremental costs per DALY averted of reactive vaccination were $2 770 and $370, respectively, for vaccine price set at $5 and $1. Assuming herd immunity, the corresponding cost was $980 with vaccine price of $5, and the programme was cost-saving with a vaccine price of $1. Results were most sensitive to case-fatality rate, per-dose vaccine price, and the size of the outbreak. Reactive vaccination has the potential to be a cost-effective measure to contain cholera outbreaks in countries at high risk. However, the feasibility of implementation should be further evaluated, and caution is warranted in extrapolating the findings to different settings in the absence of other in-depth studies.

Development of the simulation system {open_quotes}IMPACT{close_quotes} for analysis of nuclear power plant severe accidents

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

Naitoh, Masanori; Ujita, Hiroshi; Nagumo, Hiroichi

1997-07-01

The Nuclear Power Engineering Corporation (NUPEC) has initiated a long-term program to develop the simulation system {open_quotes}IMPACT{close_quotes} for analysis of hypothetical severe accidents in nuclear power plants. IMPACT employs advanced methods of physical modeling and numerical computation, and can simulate a wide spectrum of senarios ranging from normal operation to hypothetical, beyond-design-basis-accident events. Designed as a large-scale system of interconnected, hierarchical modules, IMPACT`s distinguishing features include mechanistic models based on first principles and high speed simulation on parallel processing computers. The present plan is a ten-year program starting from 1993, consisting of the initial one-year of preparatory work followed bymore » three technical phases: Phase-1 for development of a prototype system; Phase-2 for completion of the simulation system, incorporating new achievements from basic studies; and Phase-3 for refinement through extensive verification and validation against test results and available real plant data.« less

Detecting Change in Longitudinal Social Networks

DTIC Science & Technology

2011-01-01

organizational change may cause a manager to investigate the presence of good initiatives and see them through to implementation. On the other hand, terrorist... marketing campaigns and media on social behavior. Initial Construct populations, social and knowledge networks, can be hypothetical or real (Carley...mality Data tic data set f any) are 9 independe easible for th ication probl d, this is simp the radio lso known as e unit as a res significant t

Reactive transport modeling of ⁹⁰Sr sorption in reactive sandpacks.

PubMed

Yin, Jun; Jeen, Sung-Wook; Lee, David R; Mayer, K Ulrich

2014-09-15

Strontium-90 ((90)Sr) is one of the most problematic radioactive contaminants in groundwater at nuclear sites. Although (90)Sr is retarded relative to groundwater flow, it is sufficiently mobile and long-lived to require treatment in many hydrogeological settings. A detailed study was performed on the practicality of using granular clinoptilolite as a sandpack around groundwater wells where groundwater is contaminated with (90)Sr and the water table must be lowered. The effectiveness of the reactive sandpack concept and the mechanisms controlling (90)Sr attenuation was investigated by numerical analysis of data obtained from four in situ column experiments. The experiments spanned the range of pore-water velocities that would occur during radial flow through granular clinoptilolite sandpacks. A kinetic sorption model was required to adequately reproduce the experimentally observed (90)Sr behavior. Calibrated first-order kinetic rates were correlated with pore-water velocities. After calibration, three sorption models were used to simulate (90)Sr attenuation for four hypothetical pumping scenarios. Results show that a velocity-dependent kinetic model accurately simulates the observed early breakthrough for high pore-water velocities. The results indicate (1) that reactive sandpacks have good potential for in situ remediation and construction dewatering and (2) that quantitative modeling can aid in the design and application of this novel technique. Copyright © 2014 Elsevier B.V. All rights reserved.

Teacher Training for Secondary Education and Graduates' Entrance into the Teaching Profession

ERIC Educational Resources Information Center

Rots, Isabel; Aelterman, Antonia

2008-01-01

This study focuses on the relationship between teacher education and graduates' intended and actual entrance into teaching. Moreover, it explores how this relationship differs for two types of initial teacher training for secondary education. A hypothetical model of graduates' entrance into the teaching profession comprising empirically grounded…

Iodine-catalyzed diazo activation to access radical reactivity.

PubMed

Li, Pan; Zhao, Jingjing; Shi, Lijun; Wang, Jin; Shi, Xiaodong; Li, Fuwei

2018-05-17

Transition-metal-catalyzed diazo activation is a classical way to generate metal carbene, which are valuable intermediates in synthetic organic chemistry. An alternative iodine-catalyzed diazo activation is disclosed herein under either photo-initiated or thermal-initiated conditions, which represents an approach to enable carbene radical reactivity. This metal-free diazo activation strategy were successfully applied into olefin cyclopropanation and epoxidation, and applying this method to pyrrole synthesis under thermal-initiated conditions further demonstrates the unique reactivity using this method over typical metal-catalyzed conditions.

Study on communications costs for Columbus utilization

NASA Astrophysics Data System (ADS)

Nielsen, Svend Moller; Sorensen, Nicolaj

1988-09-01

On the basis of a hypothetical communications scenario established for cost calculations, the expected communications costs for Columbus utilization in the year 1995 and onwards to the year 2025, are estimated to provide initial considerations for a charging policy in relation to potential Columbus users. A hypothetical sample of five European countries is established, and current telecommunications tariffs for the data, voice, and video communications required for the Columbus utilization in and between these five countries and the USA are identified. Technological, political, and commercial development trends are analyzed as to their likely influences on future telecommunications tariff development. Communications costs for the study period are estimated, assuming telecommunications administrations to be providers of service and considering estimated equipment and operations costs. Alternative communications solutions are indicated.

Summary and evaluation: fuel dynamics loss-of-flow experiments (tests L2, L3, and L4)

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

Barts, E.W.; Deitrich, L.W.; Eberhart, J.G.

1975-09-01

Three similar experiments conducted to support the analyses of hypothetical LMFBR unprotected-loss-of-flow accidents are summarized and evaluated. The tests, designated L2, L3, and L4, provided experimental data against which accident-analysis codes could be compared, so as to guide further analysis and modeling of the initiating phases of the hypothetical accident. The tests were conducted using seven-pin bundles of mixed-oxide fuel pins in Mark-II flowing-sodium loops in the TREAT reactor. Test L2 used fresh fuel. Tests L3 and L4 used irradiated fuel pins having, respectively, ''intermediate-power'' (no central void) and ''high-power'' (fully developed central void) microstructure. 12 references. (auth)

Formation of NDMA and halogenated DBPs by chloramination of tertiary amines: the influence of bromide ion.

PubMed

Le Roux, Julien; Gallard, Hervé; Croué, Jean-Philippe

2012-02-07

The formation of NDMA and other DBPs (including THMs, HANs, and HKs) has been investigated by chloramination of several tertiary amines in the absence and presence of bromide ion. NDMA formation from the most reactive tertiary amines (e.g., dimethylaminomethylfurfuryl alcohol or DMP30) was enhanced in the presence of bromide due to the formation of brominated oxidant species such as bromochloramine (NHBrCl) and the hypothetical UDMH-Br as an intermediate. The formation of NDMA by chloramination of less reactive model compounds was inhibited in the presence of bromide. This can be explained by competitive reactions leading to the production of brominated DBPs (i.e., THMs). In the presence of bromide, the formation of brominated THMs during chloramination can be attributed to the presence of small amounts of HOBr produced by the decomposition of chloramines and bromamines. The results are of particular interest to understand NDMA formation mechanisms, especially during chloramination of wastewaters impacted by anthropogenic tertiary amines and containing bromide ion.

[Chronic periodontitis with Takayasu arteritis: a case report].

PubMed

Gao, Wei; Luan, Qing-xian

2015-10-18

This case report concerns a 23-year-old woman with chronic periodontitis who had been previously diagnosed with Takayasu arteritis (TA). Her erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level were decreased before and 3 months after non-surgical periodontal therapy with no change in her prescribed medications (ESR from 31.00 mm/h to 23.0 mm/h, CRP from 21.40 mg/L to 18.46 mm/h). Through the occasional findings, we raised a hypothetical analysis about the potential relationship between periodontitis and TA with respect to inflammatory factors, bacteria and medication. Further studies of large samples are needed to verify the findings.

Intrinsic platelet reactivity before start with clopidogrel as predictor for on-clopidogrel platelet function and long-term clinical outcome.

PubMed

Hochholzer, Willibald; Valina, Christian M; Bömicke, Timo; Amann, Michael; Stratz, Christian; Nührenberg, Thomas; Trenk, Dietmar; Neumann, Franz-Josef

2015-07-01

High on-clopidogrel platelet reactivity is associated with worse clinical outcome. Previous data suggest that intrinsic platelet reactivity before initiation of clopidogrel contributes significantly to on-clopidogrel platelet reactivity. It is unknown whether intrinsic reactivity can sufficiently predict on-clopidogrel reactivity and therefore identify patients with insufficient response to clopidogrel before initiation of treatment and at risk for worse clinical outcome. This analysis included 765 consecutive patients undergoing elective coronary stent implantation. Platelet reactivity was assessed by light transmission aggregometry (5 µM ADP) before administration of clopidogrel 600mg and after intake of first maintenance dose of clopidogrel on day 1 following coronary stenting. Patients were followed for up to seven years. The combined primary endpoint was death of any cause or non-fatal myocardial infarction. Intrinsic and on-clopidogrel platelet reactivity were significant correlated (r=0.31; p < 0.001). Among all tested clinical and genetic factors including the cytochrome P450 2C19*2 polymorphism, intrinsic platelet reactivity was the strongest predictor for on-clopidogrel platelet reactivity. However, intrinsic platelet reactivity could only explain 8 % of variability of on-clopidogrel platelet function. Only on-treatment platelet reactivity was predictive for long-term clinical outcome (HR 1.47, 95 % CI 1.05-2.05; p = 0.02) whereas intrinsic platelet reactivity was not (HR 1.03, 95 % CI 0.74-1.43; p = 0.86). In conclusion, intrinsic platelet reactivity before initiation of clopidogrel is the strongest predictor of early on-clopidogrel platelet reactivity but can only explain a minor proportion of its variability and is not significantly associated with clinical outcome. Thus, baseline testing cannot substitute on-clopidogrel platelet function testing.

Finite Feedback Cycling in Structural Equation Models

ERIC Educational Resources Information Center

Hayduk, Leslie A.

2009-01-01

In models containing reciprocal effects, or longer causal loops, the usual effect estimates assume that any effect touching a loop initiates an infinite cycling of effects around that loop. The real world, in contrast, might permit only finite feedback cycles. I use a simple hypothetical model to demonstrate that if the world permits only a few…

A User-Centered View of Document Delivery and Interlibrary Loan.

ERIC Educational Resources Information Center

Martin, Harry S., III; Kendrick, Curtis L.

1994-01-01

Discusses reasons why libraries are being forced to seek new forms of information storage. A hypothetical scenario of user-initiated document delivery alternatives integrated with a search process used by a professor using the Harvard OnLine Library Information System is presented. Extensive notes elaborate on the process and the technology…

Wind gusts and plant aeroelasticity effects on the aerodynamics of pollen shedding: a hypothetical turbulence-initiated wind-pollination mechanism.

PubMed

Urzay, Javier; Llewellyn Smith, Stefan G; Thompson, Elinor; Glover, Beverley J

2009-08-21

Plant reproduction depends on pollen dispersal. For anemophilous (wind-pollinated) species, such as grasses and many trees, shedding pollen from the anther must be accomplished by physical mechanisms. The unknown nature of this process has led to its description as the 'paradox of pollen liberation'. A simple scaling analysis, supported by experimental measurements on typical wind-pollinated plant species, is used to estimate the suitability of previous resolutions of this paradox based on wind-gust aerodynamic models of fungal-spore liberation. According to this scaling analysis, the steady Stokes drag force is found to be large enough to liberate anemophilous pollen grains, and unsteady boundary-layer forces produced by wind gusts are found to be mostly ineffective since the ratio of the characteristic viscous time scale to the inertial time scale of acceleration of the wind stream is a small parameter for typical anemophilous species. A hypothetical model of a stochastic aeroelastic mechanism, initiated by the atmospheric turbulence typical of the micrometeorological conditions in the vicinity of the plant, is proposed to contribute to wind pollination.

Model-Based Structural Health Monitoring of Fatigue Damage Test-Bed Specimens

DTIC Science & Technology

2011-11-15

the hull welds or notches along component edges are good initial candidates for the hypothetical damage initiation areas. The branching process adds...to it off-center. The base plate and the stiffener plate are rigidly welded by a tungsten inert gas ( TIG ) weld . Three different crack paths...shown in Figure 9(a), an 18 in long stiffener plate has been welded to each of the tested plates with 0.625 in long discrete TIG welds at 5 locations

An Optimal Design for Placements of Tsunami Observing Systems Around the Nankai Trough, Japan

NASA Astrophysics Data System (ADS)

Mulia, I. E.; Gusman, A. R.; Satake, K.

2017-12-01

Presently, there are numerous tsunami observing systems deployed in several major tsunamigenic regions throughout the world. However, documentations on how and where to optimally place such measurement devices are limited. This study presents a methodological approach to select the best and fewest observation points for the purpose of tsunami source characterizations, particularly in the form of fault slip distributions. We apply the method to design a new tsunami observation network around the Nankai Trough, Japan. In brief, our method can be divided into two stages: initialization and optimization. The initialization stage aims to identify favorable locations of observation points, as well as to determine the initial number of observations. These points are generated based on extrema of an empirical orthogonal function (EOF) spatial modes derived from 11 hypothetical tsunami events in the region. In order to further improve the accuracy, we apply an optimization algorithm called a mesh adaptive direct search (MADS) to remove redundant measurements from the initially generated points by the first stage. A combinatorial search by the MADS will improve the accuracy and reduce the number of observations simultaneously. The EOF analysis of the hypothetical tsunamis using first 2 leading modes with 4 extrema on each mode results in 30 observation points spread along the trench. This is obtained after replacing some clustered points within the radius of 30 km with only one representative. Furthermore, the MADS optimization can improve the accuracy of the EOF-generated points by approximately 10-20% with fewer observations (23 points). Finally, we compare our result with the existing observation points (68 stations) in the region. The result shows that the optimized design with fewer number of observations can produce better source characterizations with approximately 20-60% improvement of accuracies at all the 11 hypothetical cases. It should be note, however, that our design is a tsunami-based approach, some of the existing observing systems are equipped with additional devices to measure other parameter of interests, i.e., for monitoring seismic activities.

Micro-chip initiator realized by integrating Al/CuO multilayer nanothermite on polymeric membrane

NASA Astrophysics Data System (ADS)

Taton, G.; Lagrange, D.; Conedera, V.; Renaud, L.; Rossi, C.

2013-10-01

We have developed a new nanothermite based polymeric electro-thermal initiator for non-contact ignition of a propellant. A reactive Al/CuO multilayer nanothermite resides on a 100 µm thick SU-8/PET (polyethyleneterephtalate) membrane to insulate the reactive layer from the silicon bulk substrate. When current is supplied to the initiator, the chemical reaction Al+CuO occurs and sparkles are spread to a distance of several millimeters. A micro-manufacturing process for fabricating the initiator is presented and the electrical behaviors of the ignition elements are also investigated. The characteristics of the initiator made on a 100 µm thick SU-8/PET membrane were compared to two bulk electro-thermal initiators: one on a silicon and one on a Pyrex substrate. The PET devices give 100% of Al/CuO ignition success for an electrical current >250 mA. Glass based reactive initiators give 100% of Al/CuO ignition success for an electrical current >500 mA. Reactive initiators directly on silicon cannot initiate even with a 4 A current. At low currents (<1 A), the initiation time is two orders of magnitude longer for Pyrex initiator compared to those obtained for PET initiator technology. We also observed that, the Al/CuO thermite film on PET membrane reacts within 1 ms (sparkles duration) whereas it reacts within 4 ms on Pyrex. The thermite reaction is 40 times greater in intensity using the PET substrate in comparison to Pyrex.

Social and monetary incentives counteract fear-driven avoidance: Evidence from approach-avoidance decisions.

PubMed

Pittig, Andre; Hengen, Kristina; Bublatzky, Florian; Alpers, Georg W

2018-04-22

The reduction of avoidance behavior is a central target in the treatment of anxiety disorders, but it has rarely been studied how approach of fear-relevant stimuli may be initiated. In two studies, the impact of hypothetical monetary and symbolic social incentives on approach-avoidance behavior was examined. In Study 1, individuals high or low on fear of spiders (N = 84) could choose to approach a fear-relevant versus a neutral stimulus, which were equally rewarded. In a subsequent micro-intervention, approaching the fear-relevant stimulus was differentially rewarded either by monetary or social incentives. In Study 2 (N = 76), initial incentives for approach were discontinued to investigate the stability of approach. Hypothetical monetary and symbolic social incentives reduced or eliminated initial avoidance, even in highly fearful individuals. Approach resulted in a decrease of self-reported aversiveness towards the fear-relevant stimulus. However, even after successful approach, fearful individuals showed significant avoidance behavior when incentives for approach were discontinued. Future research should investigate the long-term effects of prolonged approach incentives on multiple levels of fear (e.g., self-report, behavioral, physiological). It should also be tested if such an intervention actually improves compliance with exposure based interventions. The present findings highlight that incentives are useful to initiate initial approach towards a feared stimulus. Although incentive-based approach may neither fully eliminate avoidance nor negative feelings towards the feared stimulus, such operant interventions may set the stage for more extensive extinction training. Copyright © 2018 Elsevier Ltd. All rights reserved.

Exploring the cause of initially reactive bovine brains on rapid tests for BSE

PubMed Central

Dudas, Sandor; James, Jace; Anderson, Renee; Czub, Stefanie

2015-01-01

ABSTRACT Bovine spongiform encephalopathy (BSE) is an invariably fatal prion disease of cattle. The identification of the zoonotic potential of BSE prompted safety officials to initiate surveillance testing for this disease. In Canada, BSE surveillance is primarily focused on high risk cattle including animals which are dead, down and unable to rise, diseased or distressed. This targeted surveillance results in the submission of brain samples with a wide range of tissue autolysis and associated contaminants. These contaminants have the potential to interfere with important steps of surveillance tests resulting in initially positive test results requiring additional testing to confirm the disease status of the animal. The current tests used for BSE screening in Canada utilize the relative protease resistance of the prion protein gained when it misfolds from PrPC to PrPSc as part of the disease process. Proteinase K completely digests PrPC in normal brains, but leaves most of the PrPSc in BSE positive brains intact which is detected using anti-prion antibodies. These tests are highly reliable but occasionally give rise to initially reactive/false positive results. Test results for these reactive samples were close to the positive/negative cut-off on a sub set of test platforms. This is in contrast to all of the previous Canadian positive samples whose numeric values on these same test platforms were 10 to 100 fold greater than the test positive/negative cut-off. Here we explore the potential reason why a sample is repeatedly positive on a sub-set of rapid surveillance tests, but negative on other test platforms. In order to better understand and identify what might cause these initial reactions, we have conducted a variety of rapid and confirmatory assays as well as bacterial isolation and identification on BSE positive, negative and initially reactive samples. We observed high levels of viable bacterial contamination in initially reactive samples suggesting that the reactivity may be related to bacterial factors. Several bacteria isolated from the initially reactive samples have characteristics of biofilm forming bacteria and this extracellular matrix might play a role in preventing complete digestion of PrPC in these samples. PMID:26689488

Adaptive and Context-Aware Reconciliation of Reactive and Pro-active Behavior in Evolving Systems

NASA Astrophysics Data System (ADS)

Trajcevski, Goce; Scheuermann, Peter

One distinct characteristics of the context-aware systems is their ability to react and adapt to the evolution of the environment, which is often a result of changes in the values of various (possibly correlated) attributes. Based on these changes, reactive systems typically take corrective actions, e.g., adjusting parameters in order to maintain the desired specifications of the system's state. Pro-active systems, on the other hand, may change the mode of interaction with the environment as well as the desired goals of the system. In this paper we describe our (ECA)2 paradigm for reactive behavior with proactive impact and we present our ongoing work and vision for a system that is capable of context-aware adaptation, while ensuring the maintenance of a set of desired behavioral policies. Our main focus is on developing a formalism that provides tools for expressing normal, as well as defeasible and/or exceptional specification. However, at the same time, we insist on a sound semantics and the capability of answering hypothetical "what-if" queries. Towards this end, we introduce the high-level language L_{ EAR} that can be used to describe the dynamics of the problem domain, specify triggers under the (ECA)2 paradigm, and reason about the consequences of the possible evolutions.

Crossing the dividing surface of transition state theory. III. Once and only once. Selecting reactive trajectories

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

Lorquet, J. C., E-mail: jc.lorquet@ulg.ac.be

2015-09-14

The purpose of the present work is to determine initial conditions that generate reacting, recrossing-free trajectories that cross the conventional dividing surface of transition state theory (i.e., the plane in configuration space passing through a saddle point of the potential energy surface and perpendicular to the reaction coordinate) without ever returning to it. Local analytical equations of motion valid in the neighborhood of this planar surface have been derived as an expansion in Poisson brackets. We show that the mere presence of a saddle point implies that reactivity criteria can be quite simply formulated in terms of elements of thismore » series, irrespective of the shape of the potential energy function. Some of these elements are demonstrated to be equal to a sum of squares and thus to be necessarily positive, which has a profound impact on the dynamics. The method is then applied to a three-dimensional model describing an atom-diatom interaction. A particular relation between initial conditions is shown to generate a bundle of reactive trajectories that form reactive cylinders (or conduits) in phase space. This relation considerably reduces the phase space volume of initial conditions that generate recrossing-free trajectories. Loci in phase space of reactive initial conditions are presented. Reactivity is influenced by symmetry, as shown by a comparative study of collinear and bent transition states. Finally, it is argued that the rules that have been derived to generate reactive trajectories in classical mechanics are also useful to build up a reactive wave packet.« less

The Effects of Methylphenidate on Discounting of Delayed Rewards in ADHD

PubMed Central

Shiels, Keri; Hawk, Larry W.; Reynolds, Brady; Mazzullo, Rebecca; Rhodes, Jessica; Pelham, William E.; Waxmonsky, James G.; Gangloff, Brian P.

2010-01-01

Impulsivity is a central component of attention-deficit/hyperactivity disorder (ADHD). Delay discounting, or a preference for smaller, immediate rewards over larger, delayed rewards is considered an important aspect of impulsivity, and delay-related impulsivity has been emphasized in etiological models of ADHD. The current study examined whether stimulant medication, an effective treatment for ADHD, reduces discounting of delayed experiential and hypothetical rewards among 49 children (age 9–12 years) with ADHD. Following a practice day, participants completed a 3-day double-blind placebo-controlled acute medication assessment. Active doses were long-acting methylphenidate (Concerta), with the nearest equivalents of 0.3 and 0.6 mg/kg TID immediate-release methylphenidate. On each testing day, participants completed experiential (real-world money in real time) and hypothetical discounting tasks. Relative to placebo, methylphenidate reduced discounting of delayed experiential rewards, but not hypothetical rewards. Broadly consistent with etiological models that emphasize delay-related impulsivity among children with ADHD, these findings provide initial evidence that stimulant medication reduces delay discounting among those with the disorder. The present results also draw attention to task parameters that may influence the sensitivity of various delay discounting measures to medication effects. PMID:19803628

Delay, probability, and social discounting in a public goods game.

PubMed

Jones, Bryan A; Rachlin, Howard

2009-01-01

A human social discount function measures the value to a person of a reward to another person at a given social distance. Just as delay discounting is a hyperbolic function of delay, and probability discounting is a hyperbolic function of odds-against, social discounting is a hyperbolic function of social distance. Experiment 1 obtained individual social, delay, and probability discount functions for a hypothetical $75 reward; participants also indicated how much of an initial $100 endowment they would contribute to a common investment in a public good. Steepness of discounting correlated, across participants, among all three discount dimensions. However, only social and probability discounting were correlated with the public-good contribution; high public-good contributors were more altruistic and also less risk averse than low contributors. Experiment 2 obtained social discount functions with hypothetical $75 rewards and delay discount functions with hypothetical $1,000 rewards, as well as public-good contributions. The results replicated those of Experiment 1; steepness of the two forms of discounting correlated with each other across participants but only social discounting correlated with the public-good contribution. Most participants in Experiment 2 predicted that the average contribution would be lower than their own contribution.

Looking for the Prototype of Teaching Expertise: An Initial Attempt in Taiwan.

ERIC Educational Resources Information Center

Lin, Sunny S. J.

This study followed Sternberg and Horvath's (1995) prototype view to sketch a teaching expertise schema as the hypothetical model. An interview of 13 novice, beginning, and expert teachers was used to examine the adequacy of the model. The participants were asked to comment on slides of classroom events. Their think-out-loud protocols were coded…

Neural Reactivity to Emotional Faces Mediates the Relationship Between Childhood Empathy and Adolescent Prosocial Behavior

PubMed Central

Flournoy, John C.; Pfeifer, Jennifer H.; Moore, William E.; Tackman, Allison; Masten, Carrie L.; Mazziotta, John C.; Iacoboni, Marco; Dapretto, Mirella

2017-01-01

Reactivity to others' emotions can result in empathic concern (EC), an important motivator of prosocial behavior, but can also result in personal distress (PD), which may hinder prosocial behavior. Examining neural substrates of emotional reactivity may elucidate how EC and PD differentially influence prosocial behavior. Participants (N=57) provided measures of EC, PD, prosocial behavior, and neural responses to emotional expressions at age 10 and 13. Initial EC predicted subsequent prosocial behavior. Initial EC and PD predicted subsequent reactivity to emotions in the inferior frontal gyrus (IFG) and inferior parietal lobule, respectively. Activity in the IFG, a region linked to mirror neuron processes, as well as cognitive control and language, mediated the relation between initial EC and subsequent prosocial behavior. PMID:28262939

Kinetics of zero-valent iron reductive transformation of the anthraquinone dye Reactive Blue 4.

PubMed

Epolito, William J; Yang, Hanbae; Bottomley, Lawrence A; Pavlostathis, Spyros G

2008-12-30

The effect of operational conditions and initial dye concentration on the reductive transformation (decolorization) of the textile dye Reactive Blue 4 (RB4) using zero-valent iron (ZVI) filings was evaluated in batch assays. The decolorization rate increased with decreasing pH and increasing temperature, mixing intensity, and addition of salt (100gL(-1) NaCl) and base (3gL(-1) Na2CO3 and 1gL(-1) NaOH), conditions typical of textile reactive dyebaths. ZVI RB4 decolorization kinetics at a single initial dye concentration were evaluated using a pseudo first-order model. Under dyebath conditions and at an initial RB4 concentration of 1000mgL(-1), the pseudo first-order rate constant (kobs) was 0.029+/-0.006h(-1), corresponding to a half-life of 24.2h and a ZVI surface area-normalized rate constant (kSA) of 2.9x10(-4)Lm(-2)h(-1). However, as the initial dye concentration increased, the kobs decreased, suggesting saturation of ZVI surface reactive sites. Non-linear regression of initial decolorization rate values as a function of initial dye concentration, based on a reactive sites saturation model, resulted in a maximum decolorization rate (Vm) of 720+/-88mgL(-1)h(-1) and a half-saturation constant (K) of 1299+/-273mgL(-1). Decolorization of RB4 via a reductive transformation, which was essentially irreversible (2-5% re-oxidation), is believed to be the dominant decolorization mechanism. However, some degree of RB4 irreversible sorption cannot be completely discounted. The results of this study show that ZVI treatment is a promising technology for the decolorization of commercial, anthraquinone-bearing, spent reactive dyebaths.

The hepatitis C cascade of care: identifying priorities to improve clinical outcomes.

PubMed

Linas, Benjamin P; Barter, Devra M; Leff, Jared A; Assoumou, Sabrina A; Salomon, Joshua A; Weinstein, Milton C; Kim, Arthur Y; Schackman, Bruce R

2014-01-01

As highly effective hepatitis C virus (HCV) therapies emerge, data are needed to inform the development of interventions to improve HCV treatment rates. We used simulation modeling to estimate the impact of loss to follow-up on HCV treatment outcomes and to identify intervention strategies likely to provide good value for the resources invested in them. We used a Monte Carlo state-transition model to simulate a hypothetical cohort of chronically HCV-infected individuals recently screened positive for serum HCV antibody. We simulated four hypothetical intervention strategies (linkage to care; treatment initiation; integrated case management; peer navigator) to improve HCV treatment rates, varying efficacies and costs, and identified strategies that would most likely result in the best value for the resources required for implementation. Sustained virologic responses (SVRs), life expectancy, quality-adjusted life expectancy (QALE), costs from health system and program implementation perspectives, and incremental cost-effectiveness ratios (ICERs). We estimate that imperfect follow-up reduces the real-world effectiveness of HCV therapies by approximately 75%. In the base case, a modestly effective hypothetical peer navigator program maximized the number of SVRs and QALE, with an ICER compared to the next best intervention of $48,700/quality-adjusted life year. Hypothetical interventions that simultaneously addressed multiple points along the cascade provided better outcomes and more value for money than less costly interventions targeting single steps. The 5-year program cost of the hypothetical peer navigator intervention was $14.5 million per 10,000 newly diagnosed individuals. We estimate that imperfect follow-up during the HCV cascade of care greatly reduces the real-world effectiveness of HCV therapy. Our mathematical model shows that modestly effective interventions to improve follow-up would likely be cost-effective. Priority should be given to developing and evaluating interventions addressing multiple points along the cascade rather than options focusing solely on single points.

The Hepatitis C Cascade of Care: Identifying Priorities to Improve Clinical Outcomes

PubMed Central

Linas, Benjamin P.; Barter, Devra M.; Leff, Jared A.; Assoumou, Sabrina A.; Salomon, Joshua A.; Weinstein, Milton C.; Kim, Arthur Y.; Schackman, Bruce R.

2014-01-01

Background As highly effective hepatitis C virus (HCV) therapies emerge, data are needed to inform the development of interventions to improve HCV treatment rates. We used simulation modeling to estimate the impact of loss to follow-up on HCV treatment outcomes and to identify intervention strategies likely to provide good value for the resources invested in them. Methods We used a Monte Carlo state-transition model to simulate a hypothetical cohort of chronically HCV-infected individuals recently screened positive for serum HCV antibody. We simulated four hypothetical intervention strategies (linkage to care; treatment initiation; integrated case management; peer navigator) to improve HCV treatment rates, varying efficacies and costs, and identified strategies that would most likely result in the best value for the resources required for implementation. Main measures Sustained virologic responses (SVRs), life expectancy, quality-adjusted life expectancy (QALE), costs from health system and program implementation perspectives, and incremental cost-effectiveness ratios (ICERs). Results We estimate that imperfect follow-up reduces the real-world effectiveness of HCV therapies by approximately 75%. In the base case, a modestly effective hypothetical peer navigator program maximized the number of SVRs and QALE, with an ICER compared to the next best intervention of $48,700/quality-adjusted life year. Hypothetical interventions that simultaneously addressed multiple points along the cascade provided better outcomes and more value for money than less costly interventions targeting single steps. The 5-year program cost of the hypothetical peer navigator intervention was $14.5 million per 10,000 newly diagnosed individuals. Conclusions We estimate that imperfect follow-up during the HCV cascade of care greatly reduces the real-world effectiveness of HCV therapy. Our mathematical model shows that modestly effective interventions to improve follow-up would likely be cost-effective. Priority should be given to developing and evaluating interventions addressing multiple points along the cascade rather than options focusing solely on single points. PMID:24842841

Multiphysics Nuclear Thermal Rocket Thrust Chamber Analysis

NASA Technical Reports Server (NTRS)

Wang, Ten-See

2005-01-01

The objective of this effort is t o develop an efficient and accurate thermo-fluid computational methodology to predict environments for hypothetical thrust chamber design and analysis. The current task scope is to perform multidimensional, multiphysics analysis of thrust performance and heat transfer analysis for a hypothetical solid-core, nuclear thermal engine including thrust chamber and nozzle. The multiphysics aspects of the model include: real fluid dynamics, chemical reactivity, turbulent flow, and conjugate heat transfer. The model will be designed to identify thermal, fluid, and hydrogen environments in all flow paths and materials. This model would then be used to perform non- nuclear reproduction of the flow element failures demonstrated in the Rover/NERVA testing, investigate performance of specific configurations and assess potential issues and enhancements. A two-pronged approach will be employed in this effort: a detailed analysis of a multi-channel, flow-element, and global modeling of the entire thrust chamber assembly with a porosity modeling technique. It is expected that the detailed analysis of a single flow element would provide detailed fluid, thermal, and hydrogen environments for stress analysis, while the global thrust chamber assembly analysis would promote understanding of the effects of hydrogen dissociation and heat transfer on thrust performance. These modeling activities will be validated as much as possible by testing performed by other related efforts.

Carbonylation as a Key Reaction in Anaerobic Acetone Activation by Desulfococcus biacutus

PubMed Central

Gutiérrez Acosta, Olga B.; Hardt, Norman

2013-01-01

Acetone is activated by aerobic and nitrate-reducing bacteria via an ATP-dependent carboxylation reaction to form acetoacetate as the first reaction product. In the activation of acetone by sulfate-reducing bacteria, acetoacetate has not been found to be an intermediate. Here, we present evidence of a carbonylation reaction as the initial step in the activation of acetone by the strictly anaerobic sulfate reducer Desulfococcus biacutus. In cell suspension experiments, CO was found to be a far better cosubstrate for acetone activation than CO2. The hypothetical reaction product, acetoacetaldehyde, is extremely reactive and could not be identified as a free intermediate. However, acetoacetaldehyde dinitrophenylhydrazone was detected by mass spectrometry in cell extract experiments as a reaction product of acetone, CO, and dinitrophenylhydrazine. In a similar assay, 2-amino-4-methylpyrimidine was formed as the product of a reaction between acetoacetaldehyde and guanidine. The reaction depended on ATP as a cosubstrate. Moreover, the specific activity of aldehyde dehydrogenase (coenzyme A [CoA] acylating) tested with the putative physiological substrate was found to be 153 ± 36 mU mg−1 protein, and its activity was specifically induced in extracts of acetone-grown cells. Moreover, acetoacetyl-CoA was detected (by mass spectrometry) after the carbonylation reaction as the subsequent intermediate after acetoacetaldehyde was formed. These results together provide evidence that acetoacetaldehyde is an intermediate in the activation of acetone by sulfate-reducing bacteria. PMID:23913429

Carbonylation as a key reaction in anaerobic acetone activation by Desulfococcus biacutus.

PubMed

Gutiérrez Acosta, Olga B; Hardt, Norman; Schink, Bernhard

2013-10-01

Acetone is activated by aerobic and nitrate-reducing bacteria via an ATP-dependent carboxylation reaction to form acetoacetate as the first reaction product. In the activation of acetone by sulfate-reducing bacteria, acetoacetate has not been found to be an intermediate. Here, we present evidence of a carbonylation reaction as the initial step in the activation of acetone by the strictly anaerobic sulfate reducer Desulfococcus biacutus. In cell suspension experiments, CO was found to be a far better cosubstrate for acetone activation than CO2. The hypothetical reaction product, acetoacetaldehyde, is extremely reactive and could not be identified as a free intermediate. However, acetoacetaldehyde dinitrophenylhydrazone was detected by mass spectrometry in cell extract experiments as a reaction product of acetone, CO, and dinitrophenylhydrazine. In a similar assay, 2-amino-4-methylpyrimidine was formed as the product of a reaction between acetoacetaldehyde and guanidine. The reaction depended on ATP as a cosubstrate. Moreover, the specific activity of aldehyde dehydrogenase (coenzyme A [CoA] acylating) tested with the putative physiological substrate was found to be 153 ± 36 mU mg(-1) protein, and its activity was specifically induced in extracts of acetone-grown cells. Moreover, acetoacetyl-CoA was detected (by mass spectrometry) after the carbonylation reaction as the subsequent intermediate after acetoacetaldehyde was formed. These results together provide evidence that acetoacetaldehyde is an intermediate in the activation of acetone by sulfate-reducing bacteria.

Trends in the prevalence and distribution of HTLV-1 and HTLV-2 infections in Spain.

PubMed

Treviño, Ana; Aguilera, Antonio; Caballero, Estrella; Benito, Rafael; Parra, Patricia; Eiros, Jose M; Hernandez, Araceli; Calderón, Enrique; Rodríguez, Manuel; Torres, Alvaro; García, Juan; Ramos, Jose Manuel; Roc, Lourdes; Marcaida, Goitzane; Rodríguez, Carmen; Trigo, Matilde; Gomez, Cesar; de Lejarazu, Raul Ortíz; de Mendoza, Carmen; Soriano, Vincent

2012-03-23

Although most HTLV infections in Spain have been found in native intravenous drug users carrying HTLV-2, the large immigration flows from Latin America and Sub-Saharan Africa in recent years may have changed the prevalence and distribution of HTLV-1 and HTLV-2 infections, and hypothetically open the opportunity for introducing HTLV-3 or HTLV-4 in Spain. To assess the current seroprevalence of HTLV infection in Spain a national multicenter, cross-sectional, study was conducted in June 2009. A total of 6,460 consecutive outpatients attending 16 hospitals were examined. Overall, 12% were immigrants, and their main origin was Latin America (4.9%), Africa (3.6%) and other European countries (2.8%). Nine individuals were seroreactive for HTLV antibodies (overall prevalence, 0.14%). Evidence of HTLV-1 infection was confirmed by Western blot in 4 subjects (prevalence 0.06%) while HTLV-2 infection was found in 5 (prevalence 0.08%). Infection with HTLV types 1, 2, 3 and 4 was discarded by Western blot and specific PCR assays in another two specimens initially reactive in the enzyme immunoassay. All but one HTLV-1 cases were Latin-Americans while all persons with HTLV-2 infection were native Spaniards. The overall prevalence of HTLV infections in Spain remains low, with no evidence of HTLV-3 or HTLV-4 infections so far.

Technical Basis for Peak Reactivity Burnup Credit for BWR Spent Nuclear Fuel in Storage and Transportation Systems

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

Marshall, William BJ J; Ade, Brian J; Bowman, Stephen M

2015-01-01

Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission have initiated a multiyear project to investigate application of burnup credit for boiling-water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase (1) investigates applicability of peak reactivity methods currently used in spent fuel pools (SFPs) to storage and transportation systems and (2) evaluates validation of both reactivity (k eff) calculations and burnup credit nuclide concentrations within these methods. The second phase will focus on extending burnup credit beyond peak reactivity. This paper documents the first phase, including an analysis of latticemore » design parameters and depletion effects, as well as both validation components. Initial efforts related to extended burnup credit are discussed in a companion paper. Peak reactivity analyses have been used in criticality analyses for licensing of BWR fuel in SFPs over the last 20 years. These analyses typically combine credit for the gadolinium burnable absorber present in the fuel with a modest amount of burnup credit. Gadolinium burnable absorbers are used in BWR assemblies to control core reactivity. The burnable absorber significantly reduces assembly reactivity at beginning of life, potentially leading to significant increases in assembly reactivity for burnups less than 15–20 GWd/MTU. The reactivity of each fuel lattice is dependent on gadolinium loading. The number of gadolinium-bearing fuel pins lowers initial lattice reactivity, but it has a small impact on the burnup and reactivity of the peak. The gadolinium concentration in each pin has a small impact on initial lattice reactivity but a significant effect on the reactivity of the peak and the burnup at which the peak occurs. The importance of the lattice parameters and depletion conditions are primarily determined by their impact on the gadolinium depletion. Criticality code validation for BWR burnup credit at peak reactivity requires a different set of experiments than for pressurized-water reactor burnup credit analysis because of differences in actinide compositions, presence of residual gadolinium absorber, and lower fission product concentrations. A survey of available critical experiments is presented along with a sample criticality code validation and determination of undercoverage penalties for some nuclides. The validation of depleted fuel compositions at peak reactivity presents many challenges which largely result from a lack of radiochemical assay data applicable to BWR fuel in this burnup range. In addition, none of the existing low burnup measurement data include residual gadolinium measurements. An example bias and uncertainty associated with validation of actinide-only fuel compositions is presented.« less

Relative reactivity of amino acids with chlorine in mixtures.

PubMed

Na, Chongzheng; Olson, Terese M

2007-05-01

The relative reactivity of chlorine with amino acids is an important determinant of the resulting chlorination products in systems where chlorine is the limiting reagent, for example, in the human gastrointestinal tract after consumption of chlorine-containing water, or during food preparation with chlorinated water. Since few direct determinations of the initial reactivity of chlorine with amino acids have been made, 17 amino acids were compared in this study using competitive kinetic principles. The experimental results showed that (1) most amino acids have similar initial reactivities at neutral pH; (2) amino acids with thiol groups such as methionine and cysteine are exceptionally reactive and produce sulfoxides; (3) amino acids without thiol groups primarily undergo monochlorination of the amino nitrogen; and (4) glycine and proline are the least reactive. Dichlorination was estimated to occur with approximately 26% of the amino acid groups when the total amino acid: chlorine concentrations were equal.

Kinematics of self-initiated and reactive karate punches.

PubMed

Martinez de Quel, Oscar; Bennett, Simon J

2014-03-01

This study investigated whether within-task expertise affects the reported asymmetry in execution time exhibited in reactive and self-initiated movements. Karate practitioners and no-karate practitioners were compared performing a reverse punch in reaction to an external stimulus or following the intention to produce a response (self-initiated). The task was completed following the presentation of a specific (i.e., life-size image of opponent) or general stimulus and in the presence of click trains or white noise. Kinematic analyses indicated reactive movement had shorter time to peak velocity and movement time, as well as greater accuracy than self-initiated movement. These differences were independent of participant skill level although peak velocity was higher in the karate practice group than in the no-karate practice group. Reaction time (RT) of skilled participants was facilitated by a specific stimulus. There was no effect on RT or kinematic variables of the different type of auditory cues. The results of this study indicate that asymmetry in execution time of reactive and self-initiated movement holds irrespective of within-task expertise and stimulus specificity. This could have implications for training of sports and/or relearning of tasks that require rapid and accurate movements to intercept/contact a target.

Total OH reactivity measurements for the OH-initiated oxidation of aromatic hydrocarbons in the presence of NOx

NASA Astrophysics Data System (ADS)

Sato, Kei; Nakashima, Yoshihiro; Morino, Yu; Imamura, Takashi; Kurokawa, Jun-ichi; Kajii, Yoshizumi

2017-12-01

The total OH reactivity of the secondary products formed from the OH-initiated oxidation of toluene, p-xylene, and 1,3,5-trimethylbenzene was directly measured in the presence of NOx using a laboratory environmental chamber in order to investigate unidentified reactive species in urban air. The total OH reactivity was also calculated from the concentrations of the reactants and products, which were monitored by Fourier-transform infrared spectroscopy. The difference between the measured and calculated OH reactivity, the so-called missing OH reactivity, comprised 58-81% of the total OH reactivity of the secondary products. These results suggest that the secondary products formed from the oxidation of aromatic hydrocarbons may be important candidates in accounting for the missing OH reactivity in the analyses of urban environments. The Master Chemical Mechanism (MCM) calculations were performed to predict the temporal variation in the total OH reactivity for the oxidation of aromatic hydrocarbons. The MCM calculations successfully reproduced the observed total OH reactivity when the particle and semi-volatile product concentrations were negligibly low. The MCM calculations were used to identify the missing secondary products. The results suggest that important components of the missing OH reactivity are unsaturated multifunctional products such as unsaturated dicarbonyls, unsaturated epoxydicarbonyls, and furanones.

Neural Reactivity to Emotional Faces May Mediate the Relationship Between Childhood Empathy and Adolescent Prosocial Behavior.

PubMed

Flournoy, John C; Pfeifer, Jennifer H; Moore, William E; Tackman, Allison M; Masten, Carrie L; Mazziotta, John C; Iacoboni, Marco; Dapretto, Mirella

2016-11-01

Reactivity to others' emotions not only can result in empathic concern (EC), an important motivator of prosocial behavior, but can also result in personal distress (PD), which may hinder prosocial behavior. Examining neural substrates of emotional reactivity may elucidate how EC and PD differentially influence prosocial behavior. Participants (N = 57) provided measures of EC, PD, prosocial behavior, and neural responses to emotional expressions at ages 10 and 13. Initial EC predicted subsequent prosocial behavior. Initial EC and PD predicted subsequent reactivity to emotions in the inferior frontal gyrus (IFG) and inferior parietal lobule, respectively. Activity in the IFG, a region linked to mirror neuron processes, as well as cognitive control and language, mediated the relation between initial EC and subsequent prosocial behavior. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

Residual shear strength variability as a primary control on movement of landslides reactivated by earthquake-induced ground motion: Implications for coastal Oregon, U.S.

USGS Publications Warehouse

Schulz, William H.; Wang, Gonghui

2014-01-01

Most large seismogenic landslides are reactivations of preexisting landslides with basal shear zones in the residual strength condition. Residual shear strength often varies during rapid displacement, but the response of residual shear zones to seismic loading is largely unknown. We used a ring shear apparatus to perform simulated seismic loading tests, constant displacement rate tests, and tests during which shear stress was gradually varied on specimens from two landslides to improve understanding of coseismic landslide reactivation and to identify shear strength models valid for slow gravitational failure through rapid coseismic failure. The landslides we studied represent many along the Oregon, U.S., coast. Seismic loading tests resulted in (1) catastrophic failure involving unbounded displacement when stresses represented those for the existing landslides and (2) limited to unbounded displacement when stresses represented those for hypothetical dormant landslides, suggesting that coseismic landslide reactivation may be significant during future great earthquakes occurring near the Oregon Coast. Constant displacement rate tests indicated that shear strength decreased exponentially during the first few decimeters of displacement but increased logarithmically with increasing displacement rate when sheared at 0.001 cm s−1 or greater. Dynamic shear resistance estimated from shear strength models correlated well with stresses observed during seismic loading tests, indicating that displacement rate and amount primarily controlled failure characteristics. We developed a stress-based approach to estimate coseismic landslide displacement that utilizes the variable shear strength model. The approach produced results that compared favorably to observations made during seismic loading tests, indicating its utility for application to landslides.

Immunoproteomic and bioinformatic approaches to identify secreted Leishmania amazonensis, L. braziliensis, and L. infantum proteins with specific reactivity using canine serum.

PubMed

Lima, B S S; Fialho, L C; Pires, S F; Tafuri, W L; Andrade, H M

2016-06-15

Leishmania spp have a wide range of hosts, and each host can harbor several Leishmania species. Dogs, for example, are frequently infected by Leishmania infantum, where they constitute its main reservoir, but they also serve as hosts for L. braziliensis and L. amazonensis. Serological tests for antibody detection are valuable tools for diagnosis of L. infantum infection due to the high levels of antibodies induced, unlike what is observed in L. amazonensis and L. braziliensis infections. Likewise, serology-based antigen-detection can be useful as an approach to diagnose any Leishmania species infection using different corporal fluid samples. Immunogenic and secreted proteins constitute powerful targets for diagnostic methods in antigen detection. As such, we performed immunoproteomic (2-DE, western blot and mass spectrometry) and bioinformatic screening to search for reactive and secreted proteins from L. amazonensis, L. braziliensis, and L. infantum. Twenty-eight non-redundant proteins were identified, among which, six were reactive only in L. amazonensis extracts, 10 in L. braziliensis extracts, and seven in L. infantum extracts. After bioinformatic analysis, seven proteins were predicted to be secreted, two of which were reactive only in L. amazonensis extracts (52kDa PDI and the glucose-regulated protein 78), one in L. braziliensis extracts (pyruvate dehydrogenase E1 beta subunit) and three in L. infantum extracts (two conserved hypothetical proteins and elongation factor 1-beta). We propose that proteins can be suitable targets for diagnostic methods based on antigen detection. Copyright © 2016 Elsevier B.V. All rights reserved.

C-reactive protein as a prognostic indicator for rebleeding in patients with nonvariceal upper gastrointestinal bleeding.

PubMed

Lee, Han Hee; Park, Jae Myung; Lee, Soon-Wook; Kang, Seung Hun; Lim, Chul-Hyun; Cho, Yu Kyung; Lee, Bo-In; Lee, In Seok; Kim, Sang Woo; Choi, Myung-Gyu

2015-05-01

In patients with acute nonvariceal upper gastrointestinal bleeding, rebleeding after an initial treatment is observed in 10-20% and is associated with mortality. To investigate whether the initial serum C-reactive protein level could predict the risk of rebleeding in patients with acute nonvariceal upper gastrointestinal bleeding. This was a retrospective study using prospectively collected data for upper gastrointestinal bleeding. Initial clinical characteristics, endoscopic features, and C-reactive protein levels were compared between those with and without 30-day rebleeding. A total of 453 patients were included (mean age, 62 years; male, 70.9%). The incidence of 30-day rebleeding was 15.9%. The mean serum C-reactive protein level was significantly higher in these patients than in those without rebleeding (P<0.001). The area under the receiver operating characteristics curve with a cutoff value of 0.5mg/dL was 0.689 (P<0.001). High serum C-reactive protein level (odds ratio, 2.98; confidence interval, 1.65-5.40) was independently associated with the 30-day rebleeding risk after adjustment for the main confounding risk factors, including age, blood pressure, and initial haemoglobin level. The serum C-reactive protein was an independent risk factor for 30-day rebleeding in patients with acute nonvariceal upper gastrointestinal bleeding, indicating a possible role as a useful screening indicator for predicting the risk of rebleeding. Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Groundwater geochemistry in the Seminole Well Field, Cedar Rapids, Iowa

USGS Publications Warehouse

Boyd, Robert A.

1999-01-01

The City of Cedar Rapids obtains its municipal water supply from four well fields in an alluvial aquifer along the Cedar River in east-central Iowa. Since 1992, the City and the U.S. Geological Survey have cooperatively studied the groundwater-flow system and water chemistry near the well fields. The geochemistry in the alluvial aquifer near the Seminole Well Field was assessed to identify potentially reactive minerals and possible chemical reactions that produce observed changes in water chemistry. Calcite, dolomite, ferrihydrite, quartz, rhodochrosite, and siderite were identified as potentially reactive minerals by calculating saturation indexes. Aluminosiicate minerals including albite, Ca-montmorillonite, gibbsite, illite, K-feldspar, and kaolinite were identified as potentially reactive minerals using hypothetical saturation indexes calculated with an assumed dissolved aluminum concentration of 1 microgram per liter. Balanced chemical equations derived from inverse-modeling techniques were used to assess chemical reactions as precipitation percolates to the water table. Calcite dissolution was predominate, but aluminosilicate weathering, cation exchange, and redox reactions also likely occurred. Microbial-catalyzed redox reactions altered the chemical composition of water infiltrating from the Cedar River into the alluvial aquifer by consuming dissolved oxygen, reducing nitrate, and increasing dissolved iron and manganese concentrations. Nitrate reduction only occurred in relatively shallow (3 to 7 meters below land surface) groundwater near the Cedar River and did not occur in water infiltrating to deeper zones of the alluvial aquifer.

A heuristic approach to incremental and reactive scheduling

NASA Technical Reports Server (NTRS)

Odubiyi, Jide B.; Zoch, David R.

1989-01-01

An heuristic approach to incremental and reactive scheduling is described. Incremental scheduling is the process of modifying an existing schedule if the initial schedule does not meet its stated initial goals. Reactive scheduling occurs in near real-time in response to changes in available resources or the occurrence of targets of opportunity. Only minor changes are made during both incremental and reactive scheduling because a goal of re-scheduling procedures is to minimally impact the schedule. The described heuristic search techniques, which are employed by the Request Oriented Scheduling Engine (ROSE), a prototype generic scheduler, efficiently approximate the cost of reaching a goal from a given state and effective mechanisms for controlling search.

Self-healing cable apparatus and methods

NASA Technical Reports Server (NTRS)

Huston, Dryver (Inventor); Esser, Brian (Inventor)

2007-01-01

Self-healing cable apparatus and methods are disclosed. The cable has a central core surrounded by an adaptive cover that can extend over the entire length of the cable or just one or more portions of the cable. The adaptive cover includes a protective layer having an initial damage resistance, and a reactive layer. When the cable is subjected to a localized damaging force, the reactive layer responds by creating a corresponding localized self-healed region. The self-healed region provides the cable with enhanced damage resistance as compared to the cable's initial damage resistance. Embodiments of the invention utilize conventional epoxies or foaming materials in the reactive layer that are released to form the self-healed region when the damaging force reaches the reactive layer.

Explosive Compations of Intermetallic-Forming Powder Mixtures for Fabricating Structural Energetic Materials

NASA Astrophysics Data System (ADS)

Du, S. W.; Aydelotte, B.; Fondse, D.; Wei, C.-T.; Jiang, F.; Herbold, E.; Vecchio, K.; Meyers, M. A.; Thadhani, N. N.

2009-12-01

A double-tube implosion geometry is used to explosively shock consolidate intermetallic-forming Ni-Al, Ta-Al, Nb-Al, Mo-Al and W-Al powder mixtures for fabricating bulk structural energetic materials, with mechanical strength and ability to undergo impact-initiated exothermic reactions. The compacts are characterized based on uniformity of micro structure and degree of densification. Mechanical properties of the compacts are characterized over the strain-rate range of 10-3 to 104 s-1. The impact reactivity is determined using rod-on-anvil experiments, in which disk-shaped compacts mounted on a copper projectile, are impacted against a steel anvil in using a 7.62 mm gas gun. The impact reactivity of the various explosively-consolidated reactive powder mixture compacts is correlated with overall kinetic energy and impact stress to determine their influence on threshold for reaction initiation. The characteristics of the various compacts, their mechanical properties and impact-initiated chemical reactivity will be described in this paper.

Real and hypothetical rewards

PubMed Central

Locey, Matthew L.; Jones, Bryan A.; Rachlin, Howard

2012-01-01

Laboratory studies of choice and decision making among real monetary rewards typically use smaller real rewards than those common in real life. When laboratory rewards are large, they are almost always hypothetical. In applying laboratory results meaningfully to real-life situations, it is important to know the extent to which choices among hypothetical rewards correspond to choices among real rewards and whether variation of the magnitude of hypothetical rewards affects behavior in meaningful ways. The present study compared real and hypothetical monetary rewards in two experiments. In Experiment 1, participants played a temporal discounting game that incorporates the logic of a repeated prisoner’s-dilemma (PD) type game versus tit-for-tat; choice of one alternative (“defection” in PD terminology) resulted in a small-immediate reward; choice of the other alternative (“cooperation” in PD terminology) resulted in a larger reward delayed until the following trial. The larger-delayed reward was greater for half of the groups than for the other half. Rewards also differed in type across groups: multiples of real nickels, hypothetical nickels or hypothetical hundred-dollar bills. All groups significantly increased choice of the larger delayed reward over the 40 trials of the experiment. Over the last 10 trials, cooperation was significantly higher when the difference between larger and smaller hypothetical rewards was greater. Reward type (real or hypothetical) made no significant difference in cooperation. In Experiment 2, real and hypothetical rewards were compared in social discounting – the decrease in value to the giver of a reward as social distance increases to the receiver of the reward. Social discount rates were well described by a hyperbolic function. Discounting rates for real and hypothetical rewards did not significantly differ. These results add to the evidence that results of experiments with hypothetical rewards validly apply in everyday life. PMID:22582110

Qualification of CASMO5 / SIMULATE-3K against the SPERT-III E-core cold start-up experiments

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

Grandi, G.; Moberg, L.

SIMULATE-3K is a three-dimensional kinetic code applicable to LWR Reactivity Initiated Accidents. S3K has been used to calculate several international recognized benchmarks. However, the feedback models in the benchmark exercises are different from the feedback models that SIMULATE-3K uses for LWR reactors. For this reason, it is worth comparing the SIMULATE-3K capabilities for Reactivity Initiated Accidents against kinetic experiments. The Special Power Excursion Reactor Test III was a pressurized-water, nuclear-research facility constructed to analyze the reactor kinetic behavior under initial conditions similar to those of commercial LWRs. The SPERT III E-core resembles a PWR in terms of fuel type, moderator,more » coolant flow rate, and system pressure. The initial test conditions (power, core flow, system pressure, core inlet temperature) are representative of cold start-up, hot start-up, hot standby, and hot full power. The qualification of S3K against the SPERT III E-core measurements is an ongoing work at Studsvik. In this paper, the results for the 30 cold start-up tests are presented. The results show good agreement with the experiments for the reactivity initiated accident main parameters: peak power, energy release and compensated reactivity. Predicted and measured peak powers differ at most by 13%. Measured and predicted reactivity compensations at the time of the peak power differ less than 0.01 $. Predicted and measured energy release differ at most by 13%. All differences are within the experimental uncertainty. (authors)« less

Thin-film optical initiator

DOEpatents

Erickson, Kenneth L.

2001-01-01

A thin-film optical initiator having an inert, transparent substrate, a reactive thin film, which can be either an explosive or a pyrotechnic, and a reflective thin film. The resultant thin-film optical initiator system also comprises a fiber-optic cable connected to a low-energy laser source, an output charge, and an initiator housing. The reactive thin film, which may contain very thin embedded layers or be a co-deposit of a light-absorbing material such as carbon, absorbs the incident laser light, is volumetrically heated, and explodes against the output charge, imparting about 5 to 20 times more energy than in the incident laser pulse.

Protection of the Lifeless Environment in the Solar System

NASA Astrophysics Data System (ADS)

Almar, I.

The main concern of planetary protection policy is how to protect the (hypothetical) extraterrestrial life against contamination and back-contamination. There is almost no interest in the preservation of the existing lifeless surfaces of extraterrestrial bodies, although some planetary transformation plans (in order to exploit hypothetical resources) were made public a long time ago. It should be remembered that planetary environments are practically unchanged since ages and damage caused by any human intervention would be irreversible. Our intention is not to prevent any commercial utilization of Solar System resources, but to make space exploration and exploitation of resources a controlled and well planned endeavor. The three main issues connected with the protection of the lifeless space environment are the following: 1/ The scientific aspect: a limited, well defined initiative to select by scientific investigation areas and objects of highest scientific priority on different celestial bodies. 2/ The legal aspect: to start the drafting of a declaration of principles supporting the protection of selected areas and objects on celestial bodies with a solid surface. It might evolve into an international legal instrument or treaty in order to limit the "free-for-all" intervention and use of Solar System resources. 3/ The societal aspect: to initiate a large scale discussion on the possible "ethical values" of the lifeless environment.

Adolescents' explicit and implicit evaluations of hypothetical and actual peers with different bullying participant roles.

PubMed

Pouwels, J Loes; Lansu, Tessa A M; Cillessen, Antonius H N

2017-07-01

This study examined how adolescents evaluate bullying at three levels of specificity: (a) the general concept of bullying, (b) hypothetical peers in different bullying participant roles, and (c) actual peers in different bullying participant roles. Participants were 163 predominantly ethnic majority adolescents in The Netherlands (58% girls; M age =16.34years, SD=0.79). For the hypothetical peers, we examined adolescents' explicit evaluations as well as their implicit evaluations. Adolescents evaluated the general concept of bullying negatively. Adolescents' explicit evaluations of hypothetical and actual peers in the bullying roles depended on their own role, but adolescents' implicit evaluations of hypothetical peers did not. Adolescents' explicit evaluations of hypothetical peers and actual peers were different. Hypothetical bullies were evaluated negatively by all classmates, whereas hypothetical victims were evaluated relatively positively compared with the other roles. However, when adolescents evaluated their actual classmates, the differences between bullies and the other roles were smaller, whereas victims were evaluated the most negatively of all roles. Further research should take into account that adolescents' evaluations of hypothetical peers differ from their evaluations of actual peers. Copyright © 2017 Elsevier Inc. All rights reserved.

Real and hypothetical monetary rewards modulate risk taking in the brain.

PubMed

Xu, Sihua; Pan, Yu; Wang, You; Spaeth, Andrea M; Qu, Zhe; Rao, Hengyi

2016-07-07

Both real and hypothetical monetary rewards are widely used as reinforcers in risk taking and decision making studies. However, whether real and hypothetical monetary rewards modulate risk taking and decision making in the same manner remains controversial. In this study, we used event-related potentials (ERP) with a balloon analogue risk task (BART) paradigm to examine the effects of real and hypothetical monetary rewards on risk taking in the brain. Behavioral data showed reduced risk taking after negative feedback (money loss) during the BART with real rewards compared to those with hypothetical rewards, suggesting increased loss aversion with real monetary rewards. The ERP data demonstrated a larger feedback-related negativity (FRN) in response to money loss during risk taking with real rewards compared to those with hypothetical rewards, which may reflect greater prediction error or regret emotion after real monetary losses. These findings demonstrate differential effects of real versus hypothetical monetary rewards on risk taking behavior and brain activity, suggesting a caution when drawing conclusions about real choices from hypothetical studies of intended behavior, especially when large rewards are used. The results have implications for future utility of real and hypothetical monetary rewards in studies of risk taking and decision making.

Reactive sintering process of ferromagnetic MnBi under high magnetic fields

NASA Astrophysics Data System (ADS)

Mitsui, Yoshifuru; Umetsu, Rie Y.; Takahashi, Kohki; Koyama, Keiichi

2018-05-01

The magnetic field effect on the reactive sintering process of MnBi was investigated. Magnetic-field-induced enhancement of the reaction was found to be exhibited at the initial stages. The coercivity field decreased with an increase in the in-field annealing time. The kinetics of the reaction were in good agreement with the diffusion-controlled reaction model. It is suggested that the decrease in activation energy at the initial stages of reaction increased the amount of formed MnBi phases, resulting in enhancement of the reaction Mn + Bi to MnBi phase by in-field reactive sintering.

Costo-Efectividad de la Proteína C Reactiva, Procalcitonina y Escala de Rochester: Tres Estrategias Diagnosticas para la Identificación de Infección Bacteriana Severa en Lactantes Febriles sin Foco.

PubMed

Antonio Buendía, Jefferson; Colantonio, Lisandro

2013-12-01

The optimal practice management of highly febrile 1- to 3-month-old children without a focal source has been controversial. The release of a conjugate pneumococcal vaccine may reduce the rate of occult bacteremia and alter the utility of empiric testing. The objective of this study was to determine the cost-effectiveness of 3 different screening strategies of Serious Bacterial Infections (SBI) in Children Presenting with Fever without Source in Argentina. Cost-effectiveness (CE) analysis was performed to compare the strategies of procalcitonin, C reactive protein and Rochester criteria. A hypothetical cohort of 10 000 children who were 1 to 3 months of age and had a fever of >39°C and no source of infection was modeled for each strategy. Our main outcome measure was incremental CE ratios. C reactive protein result in US$ 937 per correctly diagnosed cases of SBI. The additional cost per additional correct diagnosis using procalcitonin versus C reactive protein was U$6127 while Rochester criteria resulted dominated. C reactive protein is the strategy more cost-effective to detect SBI in children with Fever without Source in Argentina. Due to low proportion of correctly diagnosed cases (< 80%) of three tests in the literature and our study, however; an individualized approach for children with fever is still necessary to optimize diagnostic investigations and treatment in the different emergency care settings. © 2013 International Society for Pharmacoeconomics and Outcomes Research (ISPOR) Published by International Society for Pharmacoeconomics and Outcomes Research (ISPOR) All rights reserved.

47 CFR 69.610 - Other hypothetical net balances.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 3 2011-10-01 2011-10-01 false Other hypothetical net balances. 69.610 Section... (CONTINUED) ACCESS CHARGES Exchange Carrier Association § 69.610 Other hypothetical net balances. (a) The hypothetical net balance for an access element other than a Common Line element shall be computed as provided...

47 CFR 69.610 - Other hypothetical net balances.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Other hypothetical net balances. 69.610 Section... (CONTINUED) ACCESS CHARGES Exchange Carrier Association § 69.610 Other hypothetical net balances. (a) The hypothetical net balance for an access element other than a Common Line element shall be computed as provided...

10 CFR 71.73 - Hypothetical accident conditions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Hypothetical accident conditions. 71.73 Section 71.73... Package, Special Form, and LSA-III Tests 2 § 71.73 Hypothetical accident conditions. (a) Test procedures. Evaluation for hypothetical accident conditions is to be based on sequential application of the tests...

ENVIRONMENTAL REACTIVITY OF SOLID STATE HYDRIDE MATERIALS: MODELING AND TESTING FOR AIR AND WATER EXPOSURE

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

Anton, D.; James, C.; Cortes-Concepcion, J.

2010-05-18

To make commercially acceptable condensed phase hydrogen storage systems, it is important to understand quantitatively the risks involved in using these materials. A rigorous set of environmental reactivity tests have been developed based on modified testing procedures codified by the United Nations for the transportation of dangerous goods. Potential hydrogen storage material, 2LiBH4{center_dot}MgH2 and NH3BH3, have been tested using these modified procedures to evaluate the relative risks of these materials coming in contact with the environment in hypothetical accident scenarios. It is apparent that an ignition event will only occur if both a flammable concentration of hydrogen and sufficient thermalmore » energy were available to ignite the hydrogen gas mixture. In order to predict hydride behavior for hypothesized accident scenarios, an idealized finite element model was developed for dispersed hydride from a breached system. Empirical thermodynamic calculations based on precise calorimetric experiments were performed in order to quantify the energy and hydrogen release rates and to quantify the reaction products resulting from water and air exposure. Both thermal and compositional predictions were made with identification of potential ignition event scenarios.« less

External Validity of Contingent Valuation: Comparing Hypothetical and Actual Payments.

PubMed

Ryan, Mandy; Mentzakis, Emmanouil; Jareinpituk, Suthi; Cairns, John

2017-11-01

Whilst contingent valuation is increasingly used in economics to value benefits, questions remain concerning its external validity that is do hypothetical responses match actual responses? We present results from the first within sample field test. Whilst Hypothetical No is always an Actual No, Hypothetical Yes exceed Actual Yes responses. A constant rate of response reversals across bids/prices could suggest theoretically consistent option value responses. Certainty calibrations (verbal and numerical response scales) minimise hypothetical-actual discrepancies offering a useful solution. Helping respondents resolve uncertainty may reduce the discrepancy between hypothetical and actual payments and thus lead to more accurate policy recommendations. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Using farmers' attitude and social pressures to design voluntary Bluetongue vaccination strategies.

PubMed

Sok, J; Hogeveen, H; Elbers, A R W; Oude Lansink, A G J M

2016-10-01

Understanding the context and drivers of farmers' decision-making is critical to designing successful voluntary disease control interventions. This study uses a questionnaire based on the Reasoned Action Approach framework to assess the determinants of farmers' intention to participate in a hypothetical reactive vaccination scheme against Bluetongue. Results suggest that farmers' attitude and social pressures best explained intention. A mix of policy instruments can be used in a complementary way to motivate voluntary vaccination based on the finding that participation is influenced by both internal and external motivation. Next to informational and incentive-based instruments, social pressures, which stem from different type of perceived norms, can spur farmers' vaccination behaviour and serve as catalysts in voluntary vaccination schemes. Copyright © 2016 Elsevier B.V. All rights reserved.

VS2DRTI: Simulating Heat and Reactive Solute Transport in Variably Saturated Porous Media.

PubMed

Healy, Richard W; Haile, Sosina S; Parkhurst, David L; Charlton, Scott R

2018-01-29

Variably saturated groundwater flow, heat transport, and solute transport are important processes in environmental phenomena, such as the natural evolution of water chemistry of aquifers and streams, the storage of radioactive waste in a geologic repository, the contamination of water resources from acid-rock drainage, and the geologic sequestration of carbon dioxide. Up to now, our ability to simulate these processes simultaneously with fully coupled reactive transport models has been limited to complex and often difficult-to-use models. To address the need for a simple and easy-to-use model, the VS2DRTI software package has been developed for simulating water flow, heat transport, and reactive solute transport through variably saturated porous media. The underlying numerical model, VS2DRT, was created by coupling the flow and transport capabilities of the VS2DT and VS2DH models with the equilibrium and kinetic reaction capabilities of PhreeqcRM. Flow capabilities include two-dimensional, constant-density, variably saturated flow; transport capabilities include both heat and multicomponent solute transport; and the reaction capabilities are a complete implementation of geochemical reactions of PHREEQC. The graphical user interface includes a preprocessor for building simulations and a postprocessor for visual display of simulation results. To demonstrate the simulation of multiple processes, the model is applied to a hypothetical example of injection of heated waste water to an aquifer with temperature-dependent cation exchange. VS2DRTI is freely available public domain software. © 2018, National Ground Water Association.

Beyond Tryptophan Synthase: Identification of Genes That Contribute to Chlamydia trachomatis Survival during Gamma Interferon-Induced Persistence and Reactivation

PubMed Central

Muramatsu, Matthew K.; Brothwell, Julie A.; Stein, Barry D.; Putman, Timothy E.; Rockey, Daniel D.

2016-01-01

Chlamydia trachomatis can enter a viable but nonculturable state in vitro termed persistence. A common feature of C. trachomatis persistence models is that reticulate bodies fail to divide and make few infectious progeny until the persistence-inducing stressor is removed. One model of persistence that has relevance to human disease involves tryptophan limitation mediated by the host enzyme indoleamine 2,3-dioxygenase, which converts l-tryptophan to N-formylkynurenine. Genital C. trachomatis strains can counter tryptophan limitation because they encode a tryptophan-synthesizing enzyme. Tryptophan synthase is the only enzyme that has been confirmed to play a role in interferon gamma (IFN-γ)-induced persistence, although profound changes in chlamydial physiology and gene expression occur in the presence of persistence-inducing stressors. Thus, we screened a population of mutagenized C. trachomatis strains for mutants that failed to reactivate from IFN-γ-induced persistence. Six mutants were identified, and the mutations linked to the persistence phenotype in three of these were successfully mapped. One mutant had a missense mutation in tryptophan synthase; however, this mutant behaved differently from previously described synthase null mutants. Two hypothetical genes of unknown function, ctl0225 and ctl0694, were also identified and may be involved in amino acid transport and DNA damage repair, respectively. Our results indicate that C. trachomatis utilizes functionally diverse genes to mediate survival during and reactivation from persistence in HeLa cells. PMID:27430273

Neural Overlap in Item Representations Across Episodes Impairs Context Memory.

PubMed

Kim, Ghootae; Norman, Kenneth A; Turk-Browne, Nicholas B

2018-06-12

We frequently encounter the same item in different contexts, and when that happens, memories of earlier encounters can get reactivated. We examined how existing memories are changed as a result of such reactivation. We hypothesized that when an item's initial and subsequent neural representations overlap, this allows the initial item to become associated with novel contextual information, interfering with later retrieval of the initial context. Specifically, we predicted a negative relationship between representational similarity across repeated experiences of an item and subsequent source memory for the initial context. We tested this hypothesis in an fMRI study, in which objects were presented multiple times during different tasks. We measured the similarity of the neural patterns in lateral occipital cortex that were elicited by the first and second presentations of objects, and related this neural overlap score to subsequent source memory. Consistent with our hypothesis, greater item-specific pattern similarity was linked to worse source memory for the initial task. In contrast, greater reactivation of the initial context was associated with better source memory. Our findings suggest that the influence of novel experiences on an existing context memory depends on how reliably a shared component (i.e., item) is represented across these episodes.

Initial antibodies binding to HIV-1 gp41 in acutely infected subjects are polyreactive and highly mutated

PubMed Central

Chen, Xi; Munshaw, Supriya; Zhang, Ruijun; Marshall, Dawn J.; Vandergrift, Nathan; Whitesides, John F.; Lu, Xiaozhi; Yu, Jae-Sung; Hwang, Kwan-Ki; Gao, Feng; Markowitz, Martin; Heath, Sonya L.; Bar, Katharine J.; Goepfert, Paul A.; Montefiori, David C.; Shaw, George C.; Alam, S. Munir; Margolis, David M.; Denny, Thomas N.; Boyd, Scott D.; Marshal, Eleanor; Egholm, Michael; Simen, Birgitte B.; Hanczaruk, Bozena; Fire, Andrew Z.; Voss, Gerald; Kelsoe, Garnett; Tomaras, Georgia D.; Moody, M. Anthony; Kepler, Thomas B.

2011-01-01

The initial antibody response to HIV-1 is targeted to envelope (Env) gp41, and is nonneutralizing and ineffective in controlling viremia. To understand the origins and characteristics of gp41-binding antibodies produced shortly after HIV-1 transmission, we isolated and studied gp41-reactive plasma cells from subjects acutely infected with HIV-1. The frequencies of somatic mutations were relatively high in these gp41-reactive antibodies. Reverted unmutated ancestors of gp41-reactive antibodies derived from subjects acutely infected with HIV-1 frequently did not react with autologous HIV-1 Env; however, these antibodies were polyreactive and frequently bound to host or bacterial antigens. In one large clonal lineage of gp41-reactive antibodies, reactivity to HIV-1 Env was acquired only after somatic mutations. Polyreactive gp41-binding antibodies were also isolated from uninfected individuals. These data suggest that the majority of gp41-binding antibodies produced after acute HIV-1 infection are cross-reactive responses generated by stimulating memory B cells that have previously been activated by non–HIV-1 antigens. PMID:21987658

Critical technology areas of an SPS development and the applicability of European technology

NASA Technical Reports Server (NTRS)

Kassing, D.; Ruth, J.

1980-01-01

Possible system development and implementation scenarios for the hypothetical European part of a cooperative Satellite Power System effort are discussed, and the technology and systems requirements which could be used as an initial guideline for further evaluation studies are characterized. Examples of advanced European space technologies are described including high power microwave amplifiers, antennas, advanced structures, multi-kilowatt solar arrays, attitude and orbit control systems, and electric propulsion.

Further tests of entreaties to avoid hypothetical bias in referendum contingent valuation

Treesearch

Thomas C. Brown; Icek Ajzen; Daniel Hrubes

2003-01-01

Over-estimation of willingness to pay in contingent markets has been attributed largely to hypothetical bias. One promising approach for avoiding hypothetical bias is to tell respondents enough about such bias that they self-correct for it. A script designed for this purpose by Cummings and Taylor was used in hypothetical referenda that differed in payment amount. In...

A vaccine composed of a hypothetical protein and the eukaryotic initiation factor 5a from Leishmania braziliensis cross-protection against Leishmania amazonensis infection.

PubMed

Duarte, Mariana Costa; Lage, Daniela Pagliara; Martins, Vívian Tamietti; Costa, Lourena Emanuele; Carvalho, Ana Maria Ravena Severino; Ludolf, Fernanda; Santos, Thaís Teodoro de Oliveira; Vale, Danniele Luciana; Roatt, Bruno Mendes; Menezes-Souza, Daniel; Fernandes, Ana Paula; Tavares, Carlos Alberto Pereira; Coelho, Eduardo Antonio Ferraz

2017-02-01

In the present study, two proteins cloned from Leishmania braziliensis species, a hypothetical protein (LbHyp) and the eukaryotic initiation factor 5a (EiF5a), were evaluated to protect BALB/c mice against L. amazonensis infection. The animals were immunized with the antigens, either separately or in combination, using saponin as an immune adjuvant in both cases. Spleen cells from vaccinated and later infected mice produced significantly higher levels of protein and parasite-specific IFN-γ, IL-12, and GM-CSF, in addition to low levels of IL-4 and IL-10. Evaluating the parasite load by means of a limiting dilution technique and quantitative Real-Time PCR, vaccinated animals presented significant reductions in the parasite load in both infected tissues and organs, as well as lower footpad swelling, when compared to the control (saline and saponin) groups. The best results regarding the protection of the animals were achieved when the combined vaccine was administered into the animals. Protection was associated with an IFN-γ production against parasite antigens, which was mediated by both CD4 + and CD8 + T cells and correlated with antileishmanial nitrite production. In conclusion, data from the present study show that this polyprotein vaccine, which combines two L. braziliensis proteins, can induce protection against L. amazonensis infection. Copyright © 2016 Elsevier GmbH. All rights reserved.

Distinguishing hypothetical willingness from behavioral intentions to initiate HIV pre-exposure prophylaxis (PrEP): Findings from a large cohort of gay and bisexual men in the U.S.

PubMed

Rendina, H Jonathon; Whitfield, Thomas H F; Grov, Christian; Starks, Tyrel J; Parsons, Jeffrey T

2017-01-01

Much of the data on the acceptability of HIV Pre-Exposure Prophylaxis (PrEP) is based on willingness to take PrEP (i.e., hypothetical receptivity) rather than actual intentions (i.e., planned behavioral action) to do so. We sought to examine differences between hypothetical willingness and behavioral intentions to begin PrEP in a national sample of gay and bisexual men (GBM) across the U.S. We utilized data collected in 2015 to examine differences between those Unwilling (42.6% n = 375), Willing but not intending (41.4%, n = 365), and willing and Intending to take PrEP (15.9%, n = 140) in a multivariable, multinomial logistic regression. Men with less education had higher odds of Intending to take PrEP. Compared to men unsure about PrEP's efficacy, those who believed PrEP was at least 90% efficacious had higher odds of Intending to take PrEP. Those who saw themselves as appropriate candidates for PrEP had higher odds of Intending to take PrEP while those who saw themselves as inappropriate candidates for PrEP had lower odds of Intending to take PrEP in comparison to men unsure if they were appropriate candidates. Increased motivation for condom non-use because of perceived sexual pressure by partners was associated with higher odds of Intending to take PrEP. The groups did not differ by risk behavior nor recent STI diagnosis. Overall, the distinction between willingness and intentions to take PrEP was meaningful and may help explain disparities between PrEP acceptability and uptake. While much of the literature has focused on hypothetical willingness to take PrEP, these results highlight the importance of simultaneously assessing willingness and intentions when examining correspondence with uptake and developing interventions to increase PrEP uptake. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of the hypothetical 57Co brachytherapy source with the 192Ir source

PubMed Central

Toossi, Mohammad Taghi Bahreyni; Rostami, Atefeh; Khosroabadi, Mohsen; Khademi, Sara; Knaup, Courtney

2016-01-01

Aim of the study The 57Co radioisotope has recently been proposed as a hypothetical brachytherapy source due to its high specific activity, appropriate half-life (272 days) and medium energy photons (114.17 keV on average). In this study, Task Group No. 43 dosimetric parameters were calculated and reported for a hypothetical 57Co source. Material and methods A hypothetical 57Co source was simulated in MCNPX, consisting of an active cylinder with 3.5 mm length and 0.6 mm radius encapsulated in a stainless steel capsule. Three photon energies were utilized (136 keV [10.68%], 122 keV [85.60%], 14 keV [9.16%]) for the 57Co source. Air kerma strength, dose rate constant, radial dose function, anisotropy function, and isodose curves for the source were calculated and compared to the corresponding data for a 192Ir source. Results The results are presented as tables and figures. Air kerma strength per 1 mCi activity for the 57Co source was 0.46 cGyh–1 cm 2 mCi–1. The dose rate constant for the 57Co source was determined to be 1.215 cGyh–1U–1. The radial dose function for the 57Co source has an increasing trend due to multiple scattering of low energy photons. The anisotropy function for the 57Co source at various distances from the source is more isotropic than the 192Ir source. Conclusions The 57Co source has advantages over 192Ir due to its lower energy photons, longer half-life, higher dose rate constant and more isotropic anisotropic function. However, the 192Ir source has a higher initial air kerma strength and more uniform radial dose function. These properties make 57Co a suitable source for use in brachytherapy applications. PMID:27688731

BOLD responses in reward regions to hypothetical and imaginary monetary rewards

PubMed Central

Miyapuram, Krishna P.; Tobler, Philippe N.; Gregorios-Pippas, Lucy; Schultz, Wolfram

2015-01-01

Monetary rewards are uniquely human. Because money is easy to quantify and present visually, it is the reward of choice for most fMRI studies, even though it cannot be handed over to participants inside the scanner. A typical fMRI study requires hundreds of trials and thus small amounts of monetary rewards per trial (e.g. 5p) if all trials are to be treated equally. However, small payoffs can have detrimental effects on performance due to their limited buying power. Hypothetical monetary rewards can overcome the limitations of smaller monetary rewards but it is less well known whether predictors of hypothetical rewards activate reward regions. In two experiments, visual stimuli were associated with hypothetical monetary rewards. In Experiment 1, we used stimuli predicting either visually presented or imagined hypothetical monetary rewards, together with non-rewarding control pictures. Activations to reward predictive stimuli occurred in reward regions, namely the medial orbitofrontal cortex and midbrain. In Experiment 2, we parametrically varied the amount of visually presented hypothetical monetary reward keeping constant the amount of actually received reward. Graded activation in midbrain was observed to stimuli predicting increasing hypothetical rewards. The results demonstrate the efficacy of using hypothetical monetary rewards in fMRI studies. PMID:21985912

BOLD responses in reward regions to hypothetical and imaginary monetary rewards.

PubMed

Miyapuram, Krishna P; Tobler, Philippe N; Gregorios-Pippas, Lucy; Schultz, Wolfram

2012-01-16

Monetary rewards are uniquely human. Because money is easy to quantify and present visually, it is the reward of choice for most fMRI studies, even though it cannot be handed over to participants inside the scanner. A typical fMRI study requires hundreds of trials and thus small amounts of monetary rewards per trial (e.g. 5p) if all trials are to be treated equally. However, small payoffs can have detrimental effects on performance due to their limited buying power. Hypothetical monetary rewards can overcome the limitations of smaller monetary rewards but it is less well known whether predictors of hypothetical rewards activate reward regions. In two experiments, visual stimuli were associated with hypothetical monetary rewards. In Experiment 1, we used stimuli predicting either visually presented or imagined hypothetical monetary rewards, together with non-rewarding control pictures. Activations to reward predictive stimuli occurred in reward regions, namely the medial orbitofrontal cortex and midbrain. In Experiment 2, we parametrically varied the amount of visually presented hypothetical monetary reward keeping constant the amount of actually received reward. Graded activation in midbrain was observed to stimuli predicting increasing hypothetical rewards. The results demonstrate the efficacy of using hypothetical monetary rewards in fMRI studies. Copyright © 2011 Elsevier Inc. All rights reserved.

Elimination of falsely reactive results in a commercially-available West Nile virus IgM capture enzyme-linked immunosorbent assay by heterophilic antibody blocking reagents.

PubMed

Prince, Harry E; Lapé-Nixon, Mary; Givens, Tara S; Bradshaw, Tiffany; Nowicki, Marek J

2017-05-01

All sera initially reactive in the Focus Diagnostics West Nile virus IgM capture enzyme-linked immunosorbent assay (WNV IgM ELISA) must be retested with background subtraction to identify falsely-reactive (FR) samples due to antibodies that bind to immunoglobulins of other animal species (heterophilic antibodies). In some settings, such as pre-transplant testing of organ donors, the reporting delay associated with retesting can have an adverse impact on donor procurement and organ placement. We sought to determine if inclusion of heterophilic antibody blockers in assay conjugate could eliminate the nonspecific reactivity of FR samples. Of 6 blocking reagents evaluated using a well-characterized FR sample, immunoglobulin inhibiting reagent from Bioreclamation (IIR) and blocker from Fitzgerald Industries (BFI) were superior in their ability to inhibit false reactivity; these 2 blockers were then used to evaluate 20 additional FR and 21 truly-reactive (TR) samples. Both blockers eliminated the reactivity of 20/21 FR samples, whereas all 21 TR samples remained reactive; further, all 13 truly non-reactive (NR) samples evaluated remained non-reactive when using blocker-containing conjugate. A subset of 22 samples were tested in parallel using the initial lot and a second lot of IIR and BFI; with one exception, all samples showed the same qualitative result using both lots of a given blocker. These findings demonstrate that modification of the Focus WNV IgM screening ELISA to include heterophilic antibody blocker IIR or BFI in assay conjugate eliminates the reactivity of most FR samples, markedly reducing the number of samples requiring further testing by background subtraction. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

Adsorption of dissolved Reactive red dye from aqueous phase onto activated carbon prepared from agricultural waste.

PubMed

Senthilkumaar, S; Kalaamani, P; Porkodi, K; Varadarajan, P R; Subburaam, C V

2006-09-01

The adsorption of Reactive red dye (RR) onto Coconut tree flower carbon (CFC) and Jute fibre carbon (JFC) from aqueous solution was investigated. Adsorption studies were carried out at different initial dye concentrations, initial solution pH and adsorbent doses. The kinetic studies were also conducted; the adsorption of Reactive red onto CFC and JFC followed pseudosecond-order rate equation. The effective diffusion coefficient was evaluated to establish the film diffusion mechanism. Quantitative removal of Reactive red dye was achieved at strongly acidic conditions for both the carbons studied. The adsorption isotherm data were fitted well to Langmuir isotherm and the adsorption capacity were found to be 181.9 and 200 mg/g for CFC and JFC, respectively. The overall rate of dye adsorption appeared to be controlled by chemisorption, in this case in accordance with poor desorption studies.

Discipline responses: influences of parents' socioeconomic status, ethnicity, beliefs about parenting, stress, and cognitive-emotional processes.

PubMed

Pinderhughes, E E; Dodge, K A; Bates, J E; Pettit, G S; Zelli, A

2000-09-01

Direct and indirect precursors to parents' harsh discipline responses to hypothetical vignettes about child misbehavior were studied with data from 978 parents (59% mothers; 82% European American and 16% African American) of 585 kindergarten-aged children. SEM analyses showed that parents' beliefs about spanking and child aggression and family stress mediated a negative relation between socioeconomic status and discipline. In turn, perception of the child and cognitive-emotional processes (hostile attributions, emotional upset, worry about child's future, available alternative disciplinary strategies, and available preventive strategies) mediated the effect of stress on discipline. Similar relations between ethnicity and discipline were found (African Americans reported harsher discipline), especially among low-income parents. Societally based experiences may lead some parents to rely on accessible and coherent goals in their discipline, whereas others are more reactive.

Discipline Responses: Influences of Parents' Socioeconomic Status, Ethnicity, Beliefs About Parenting, Stress, and Cognitive–Emotional Processes

PubMed Central

Pinderhughes, Ellen E.; Dodge, Kenneth A.; Zelli, Arnaldo; Bates, John E.; Pettit, Gregory S.

2009-01-01

Direct and indirect precursors to parents' harsh discipline responses to hypothetical vignettes about child misbehavior were studied with data from 978 parents (59% mothers; 82% European American and 16% African American) of 585 kindergarten-aged children. SEM analyses showed that parents' beliefs about spanking and child aggression and family stress mediated a negative relation between socioeconomic status and discipline. In turn, perception of the child and cognitive–emotional processes (hostile attributions, emotional upset, worry about child's future, available alternative disciplinary strategies, and available preventive strategies) mediated the effect of stress on discipline. Similar relations between ethnicity and discipline were found (African Americans reported harsher discipline), especially among low-income parents. Societally based experiences may lead some parents to rely on accessible and coherent goals in their discipline, whereas others are more reactive. PMID:11025931

Cu/Mn bimetallic catalysis enables carbonylative Suzuki-Miyaura coupling with unactivated alkyl electrophiles.

PubMed

Pye, Dominic R; Cheng, Li-Jie; Mankad, Neal P

2017-07-01

A bimetallic system consisting of Cu-carbene and Mn-carbonyl co-catalysts was employed for carbonylative C-C coupling of arylboronic esters with alkyl halides, allowing for the convergent synthesis of ketones. The system operates under mild conditions and exhibits complementary reactivity to Pd catalysis. The method is compatible with a wide range of arylboronic ester nucleophiles and proceeds smoothly for both primary and secondary alkyl iodide electrophiles. Preliminary mechanistic experiments corroborate a hypothetical catalytic mechanism consisting of co-dependent cycles wherein the Cu-carbene co-catalyst engages in transmetallation to generate an organocopper nucleophile, while the Mn-carbonyl co-catalyst activates the alkyl halide electrophile by single-electron transfer and then undergoes reversible carbonylation to generate an acylmanganese electrophile. The two cycles then intersect with a heterobimetallic, product-releasing C-C coupling step.

A reactive transport model for mercury fate in soil--application to different anthropogenic pollution sources.

PubMed

Leterme, Bertrand; Blanc, Philippe; Jacques, Diederik

2014-11-01

Soil systems are a common receptor of anthropogenic mercury (Hg) contamination. Soils play an important role in the containment or dispersion of pollution to surface water, groundwater or the atmosphere. A one-dimensional model for simulating Hg fate and transport for variably saturated and transient flow conditions is presented. The model is developed using the HP1 code, which couples HYDRUS-1D for the water flow and solute transport to PHREEQC for geochemical reactions. The main processes included are Hg aqueous speciation and complexation, sorption to soil organic matter, dissolution of cinnabar and liquid Hg, and Hg reduction and volatilization. Processes such as atmospheric wet and dry deposition, vegetation litter fall and uptake are neglected because they are less relevant in the case of high Hg concentrations resulting from anthropogenic activities. A test case is presented, assuming a hypothetical sandy soil profile and a simulation time frame of 50 years of daily atmospheric inputs. Mercury fate and transport are simulated for three different sources of Hg (cinnabar, residual liquid mercury or aqueous mercuric chloride), as well as for combinations of these sources. Results are presented and discussed with focus on Hg volatilization to the atmosphere, Hg leaching at the bottom of the soil profile and the remaining Hg in or below the initially contaminated soil layer. In the test case, Hg volatilization was negligible because the reduction of Hg(2+) to Hg(0) was inhibited by the low concentration of dissolved Hg. Hg leaching was mainly caused by complexation of Hg(2+) with thiol groups of dissolved organic matter, because in the geochemical model used, this reaction only had a higher equilibrium constant than the sorption reactions. Immobilization of Hg in the initially polluted horizon was enhanced by Hg(2+) sorption onto humic and fulvic acids (which are more abundant than thiols). Potential benefits of the model for risk management and remediation of contaminated sites are discussed.

Reactivity-worth estimates of the OSMOSE samples in the MINERVE reactor R1-MOX, R2-UO2 and MORGANE/R configurations.

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

Zhong, Z.; Klann, R. T.; Nuclear Engineering Division

2007-08-03

An initial series of calculations of the reactivity-worth of the OSMOSE samples in the MINERVE reactor with the R2-UO2 and MORGANE/R core configuration were completed. The calculation model was generated using the lattice physics code DRAGON. In addition, an initial comparison of calculated values to experimental measurements was performed based on preliminary results for the R1-MOX configuration.

Meso-scale investigation of anaerobic chemical reactivity of Ti-Al-B powder mixtures under impact loading

NASA Astrophysics Data System (ADS)

Gonzales, Manny; Gurumurthy, Ashok; Gokhale, Arun; Thadhani, Naresh N.

2011-06-01

Impact-initiated anaerobic chemical reactions in Ti-Al-B reactive powder mixtures under uniaxial stress conditions are investigated using a coupled experimental/computational approach. In particular, we characterize the effects of bulk composition on the threshold impact energy to initiate reaction using rod-on-anvil type tests performed on Ti-Al-B powder compacts. Statistical volume elements (SVEs) of different bulk compositions of the powder mixtures are analyzed using the continuum hydrocode CTH to quantify the effects of strain confinement and load configuration on the overall energy of the structure. These SVEs are also validated using one-point correlation functions to characterize the volume fraction and surface area of the constituents. Based on the deformation profiles from the continuum simulations, we investigate the effect of particle size distribution and clustering of Ti and B on the threshold energy required for observed reactivity. The deformation and threshold kinetic energy of the simulated system is compared with published values of the activation energy for Ti+B reactions and Al combustion in air to assess the extent of their impact-initiated reactivity. Funded by DTRA grant No. HDTRA1-10-1-0038

Solar glare hazard analysis tool on account of determined points of time

DOEpatents

Ho, Clifford K; Sims, Cianan Alexander

2014-09-23

Technologies pertaining to determining when glare will be perceived by a hypothetical observer from a glare source and the intensity of glare that will be perceived by the hypothetical observer from the glare source are described herein. A first location of a potential source of solar glare is received, and a second location of the hypothetical observer is received. Based upon such locations, including respective elevations, and known positions of the sun over time, a determination as to when the hypothetical observer will perceive glare from the potential source of solar glare is made. Subsequently, an amount of irradiance entering the eye of the hypothetical observer is calculated to assess potential ocular hazards.

A novel concept of QUADRISO particles. Part II: Utilization for excess reactivity control.

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

Talamo, A.

2010-07-01

In high temperature reactors, burnable absorbers are utilized to manage the excess reactivity at the early stage of the fuel cycle. In this paper QUADRISO particles are proposed to manage the initial excess reactivity of high temperature reactors. The QUADRISO concept synergistically couples the decrease of the burnable poison with the decrease of the fissile materials at the fuel particle level. This mechanism is set up by introducing a burnable poison layer around the fuel kernel in ordinary TRISO particles or by mixing the burnable poison with any of the TRISO coated layers. At the beginning of life, the initialmore » excess reactivity is small because some neutrons are absorbed in the burnable poison and they are prevented from entering the fuel kernel. At the end of life, when the absorber is almost depleted, more neutrons stream into the fuel kernel of QUADRISO particles causing fission reactions. The mechanism has been applied to a prismatic high temperature reactor with europium or erbium burnable absorbers, showing a significant reduction in the initial excess reactivity of the core.« less

A novel concept of QUADRISO particles : Part II Utilization for excess reactivity control.

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

Talamo, A.

2011-01-01

In high temperature reactors, burnable absorbers are utilized to manage the excess reactivity at the early stage of the fuel cycle. In this paper QUADRISO particles are proposed to manage the initial excess reactivity of high temperature reactors. The QUADRISO concept synergistically couples the decrease of the burnable poison with the decrease of the fissile materials at the fuel particle level. This mechanism is set up by introducing a burnable poison layer around the fuel kernel in ordinary TRISO particles or by mixing the burnable poison with any of the TRISO coated layers. At the beginning of life, the initialmore » excess reactivity is small because some neutrons are absorbed in the burnable poison and they are prevented from entering the fuel kernel. At the end of life, when the absorber is almost depleted, more neutrons stream into the fuel kernel of QUADRISO particles causing fission reactions. The mechanism has been applied to a prismatic high temperature reactor with europium or erbium burnable absorbers, showing a significant reduction in the initial excess reactivity of the core.« less

Examining Hepatitis, A and B Vaccination, and HBV Reactivation Monitoring During Direct-Acting Antiviral Therapy for Hepatitis C.

PubMed

Davison, John; O'Shea, Amy; Waterbury, Nancee; Villalvazo, Yolanda

2018-05-30

The objective of this study was to examine Hepatitis A (HAV) and Hepatitis B (HBV) screening, and the risk of HBV reactivation during Hepatitis C (HCV) therapy with direct-acting antivirals (DAAs). A retrospective chart review was performed of patients treated with second generation DAA therapy from January 2014 to September 2016 at the Iowa City VA Healthcare System. In total 409 patients initiated HCV treatment, 308 (75%) and 241 (59%) were HAV and HBV vaccine eligible, respectively. Among those, 24 (8%) received a HAV vaccine, while only 20 (8%) received a HBV vaccine. Of these, 7 patients initiating an immunization in the clinic had record of completing the series. Further, 101 patients had a reactive Hepatitis B core Antibody indicating previous HBV infection, and 3 of these were tested for HBV reactivation during HCV therapy. Overall, the assessment found low rates of HAV and HBV vaccine administration, indicating missed opportunities for preventative care during HCV therapy. With the known risk of HBV reactivation with DAAs, the need for HAV and HBV screening is essential.

Hostile attributional bias and aggressive behavior in global context.

PubMed

Dodge, Kenneth A; Malone, Patrick S; Lansford, Jennifer E; Sorbring, Emma; Skinner, Ann T; Tapanya, Sombat; Tirado, Liliana Maria Uribe; Zelli, Arnaldo; Alampay, Liane Peña; Al-Hassan, Suha M; Bacchini, Dario; Bombi, Anna Silvia; Bornstein, Marc H; Chang, Lei; Deater-Deckard, Kirby; Di Giunta, Laura; Oburu, Paul; Pastorelli, Concetta

2015-07-28

We tested a model that children's tendency to attribute hostile intent to others in response to provocation is a key psychological process that statistically accounts for individual differences in reactive aggressive behavior and that this mechanism contributes to global group differences in children's chronic aggressive behavior problems. Participants were 1,299 children (mean age at year 1 = 8.3 y; 51% girls) from 12 diverse ecological-context groups in nine countries worldwide, followed across 4 y. In year 3, each child was presented with each of 10 hypothetical vignettes depicting an ambiguous provocation toward the child and was asked to attribute the likely intent of the provocateur (coded as benign or hostile) and to predict his or her own behavioral response (coded as nonaggression or reactive aggression). Mothers and children independently rated the child's chronic aggressive behavior problems in years 2, 3, and 4. In every ecological group, in those situations in which a child attributed hostile intent to a peer, that child was more likely to report that he or she would respond with reactive aggression than in situations when that same child attributed benign intent. Across children, hostile attributional bias scores predicted higher mother- and child-rated chronic aggressive behavior problems, even controlling for prior aggression. Ecological group differences in the tendency for children to attribute hostile intent statistically accounted for a significant portion of group differences in chronic aggressive behavior problems. The findings suggest a psychological mechanism for group differences in aggressive behavior and point to potential interventions to reduce aggressive behavior.

Hostile attributional bias and aggressive behavior in global context

PubMed Central

Dodge, Kenneth A.; Malone, Patrick S.; Lansford, Jennifer E.; Sorbring, Emma; Skinner, Ann T.; Tapanya, Sombat; Tirado, Liliana Maria Uribe; Zelli, Arnaldo; Alampay, Liane Peña; Al-Hassan, Suha M.; Bacchini, Dario; Bombi, Anna Silvia; Bornstein, Marc H.; Chang, Lei; Deater-Deckard, Kirby; Di Giunta, Laura; Oburu, Paul; Pastorelli, Concetta

2015-01-01

We tested a model that children’s tendency to attribute hostile intent to others in response to provocation is a key psychological process that statistically accounts for individual differences in reactive aggressive behavior and that this mechanism contributes to global group differences in children’s chronic aggressive behavior problems. Participants were 1,299 children (mean age at year 1 = 8.3 y; 51% girls) from 12 diverse ecological-context groups in nine countries worldwide, followed across 4 y. In year 3, each child was presented with each of 10 hypothetical vignettes depicting an ambiguous provocation toward the child and was asked to attribute the likely intent of the provocateur (coded as benign or hostile) and to predict his or her own behavioral response (coded as nonaggression or reactive aggression). Mothers and children independently rated the child’s chronic aggressive behavior problems in years 2, 3, and 4. In every ecological group, in those situations in which a child attributed hostile intent to a peer, that child was more likely to report that he or she would respond with reactive aggression than in situations when that same child attributed benign intent. Across children, hostile attributional bias scores predicted higher mother- and child-rated chronic aggressive behavior problems, even controlling for prior aggression. Ecological group differences in the tendency for children to attribute hostile intent statistically accounted for a significant portion of group differences in chronic aggressive behavior problems. The findings suggest a psychological mechanism for group differences in aggressive behavior and point to potential interventions to reduce aggressive behavior. PMID:26170281

Reactive Melt Infiltration Of Silicon Into Porous Carbon

NASA Technical Reports Server (NTRS)

Behrendt, Donald R.; Singh, Mrityunjay

1994-01-01

Report describes study of synthesis of silicon carbide and related ceramics by reactive melt infiltration of silicon and silicon/molybdenum alloys into porous carbon preforms. Reactive melt infiltration has potential for making components in nearly net shape, performed in less time and at lower temperature. Object of study to determine effect of initial pore volume fraction, pore size, and infiltration material on quality of resultant product.

Brief mindfulness meditation training alters psychological and neuroendocrine responses to social evaluative stress.

PubMed

Creswell, J David; Pacilio, Laura E; Lindsay, Emily K; Brown, Kirk Warren

2014-06-01

To test whether a brief mindfulness meditation training intervention buffers self-reported psychological and neuroendocrine responses to the Trier Social Stress Test (TSST) in young adult volunteers. A second objective evaluates whether pre-existing levels of dispositional mindfulness moderate the effects of brief mindfulness meditation training on stress reactivity. Sixty-six (N=66) participants were randomly assigned to either a brief 3-day (25-min per day) mindfulness meditation training or an analytic cognitive training control program. All participants completed a standardized laboratory social-evaluative stress challenge task (the TSST) following the third mindfulness meditation or cognitive training session. Measures of psychological (stress perceptions) and biological (salivary cortisol, blood pressure) stress reactivity were collected during the social evaluative stress-challenge session. Brief mindfulness meditation training reduced self-reported psychological stress reactivity but increased salivary cortisol reactivity to the TSST, relative to the cognitive training comparison program. Participants who were low in pre-existing levels of dispositional mindfulness and then received mindfulness meditation training had the greatest cortisol reactivity to the TSST. No significant main or interactive effects were observed for systolic or diastolic blood pressure reactivity to the TSST. The present study provides an initial indication that brief mindfulness meditation training buffers self-reported psychological stress reactivity, but also increases cortisol reactivity to social evaluative stress. This pattern may indicate that initially brief mindfulness meditation training fosters greater active coping efforts, resulting in reduced psychological stress appraisals and greater cortisol reactivity during social evaluative stressors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of a Simple Heat Loss Profile on a Pure Diffusion Flame

NASA Technical Reports Server (NTRS)

Ray, Anjan; Wichman, Indrek S.

1996-01-01

The presence of soot on the fuel side of a diffusion flame results in significant radiative heat losses. The influence of a fuel side heat loss zone on a pure diffusion flame established between a fuel and an oxidizer wall is investigated by assuming a hypothetical sech(sup 2) heat loss profile. The intensity and width of the loss zone are parametrically varied. The loss zone is placed at different distances from the Burke-Schumann flame location. The migration of the temperature and reactivity peaks are examined for a variety of situations. For certain cases the reaction zone breaks through the loss zone and relocates itself on the fuel side of the loss zone. In all cases the temperature and reactivity peaks move toward the fuel side with increased heat losses. The flame structure reveals that the primary balance for the energy equation is between the reaction term and the diffusion term. Extinction plots are generated for a variety of situations. The heat transfer from the flame to the walls and the radiative fraction is also investigated, and an analytical correlation formula, derived in a previous study, is shown to produce excellent predictions of our numerical results when an O(l) numerical multiplicative constant is employed.

Mindfulness Training Targets Neurocognitive Mechanisms of Addiction at the Attention-Appraisal-Emotion Interface

PubMed Central

Garland, Eric L.; Froeliger, Brett; Howard, Matthew O.

2014-01-01

Prominent neuroscience models suggest that addictive behavior occurs when environmental stressors and drug-relevant cues activate a cycle of cognitive, affective, and psychophysiological mechanisms, including dysregulated interactions between bottom-up and top-down neural processes, that compel the user to seek out and use drugs. Mindfulness-based interventions (MBIs) target pathogenic mechanisms of the risk chain linking stress and addiction. This review describes how MBIs may target neurocognitive mechanisms of addiction at the attention-appraisal-emotion interface. Empirical evidence is presented suggesting that MBIs ameliorate addiction by enhancing cognitive regulation of a number of key processes, including: clarifying cognitive appraisal and modulating negative emotions to reduce perseverative cognition and emotional arousal; enhancing metacognitive awareness to regulate drug-use action schema and decrease addiction attentional bias; promoting extinction learning to uncouple drug-use triggers from conditioned appetitive responses; reducing cue-reactivity and increasing cognitive control over craving; attenuating physiological stress reactivity through parasympathetic activation; and increasing savoring to restore natural reward processing. Treatment and research implications of our neurocognitive framework are presented. We conclude by offering a temporally sequenced description of neurocognitive processes targeted by MBIs through a hypothetical case study. Our neurocognitive framework has implications for the optimization of addiction treatment with MBIs. PMID:24454293

Reactive nitrogen impacts on ecosystem services

EPA Science Inventory

The Ecosystem Services Research Program (ESRP) is a new, multi-year research initiative under development by the Environmental Protection Agency (EPA). As one of its components, ESRP has chosen to focus on reactive Nitrogen (Nr) for stressor-specific ecosystem research through a...

Diagrams for comprehensive molecular orbital-based chemical reaction analyses: reactive orbital energy diagrams.

PubMed

Tsuneda, Takao; Singh, Raman Kumar; Chattaraj, Pratim Kumar

2018-05-15

Reactive orbital energy diagrams are presented as a tool for comprehensively performing orbital-based reaction analyses. The diagrams rest on the reactive orbital energy theory, which is the expansion of conceptual density functional theory (DFT) to an orbital energy-based theory. The orbital energies on the intrinsic reaction coordinates of fundamental reactions are calculated by long-range corrected DFT, which is confirmed to provide accurate orbital energies of small molecules, combining with a van der Waals (vdW) correlation functional, in order to examine the vdW effect on the orbital energies. By analysing the reactions based on the reactive orbital energy theory using these accurate orbital energies, it is found that vdW interactions significantly affect the orbital energies in the initial reaction processes and that more than 70% of reactions are determined to be initially driven by charge transfer, while the remaining structural deformation (dynamics)-driven reactions are classified into identity, cyclization and ring-opening, unimolecular dissociation, and H2 reactions. The reactive orbital energy diagrams, which are constructed using these results, reveal that reactions progress so as to delocalize the occupied reactive orbitals, which are determined as contributing orbitals and are usually not HOMOs, by hybridizing the unoccupied reactive orbitals, which are usually not LUMOs. These diagrams also raise questions about conventional orbital-based diagrams such as frontier molecular orbital diagrams, even for the well-established interpretation of Diels-Alder reactions.

Performance Characteristics of the Reverse Syphilis Screening Algorithm in a Population With a Moderately High Prevalence of Syphilis.

PubMed

Rourk, Angela R; Nolte, Frederick S; Litwin, Christine M

2016-11-01

With the recent introduction of automated treponemal tests, a new reverse syphilis algorithm has been proposed and now used by many clinical laboratories. We analyzed the impact of instituting the reverse screening syphilis algorithm in a laboratory that serves a geographic area with a moderately high prevalence of syphilis infection. Serum samples sent for syphilis testing were tested using a treponemal enzyme immunoassay (EIA) as the screening assay. EIA reactive samples were tested by rapid plasma reagin (RPR) and titered to end point if reactive. RPR nonreactive samples were analyzed by the Treponema pallidum particle agglutination test (TP-PA). Pertinent medical records were reviewed for false-reactive screens and samples with evidence of past syphilis infection. Among 10,060 patients tested, 502 (5%) were reactive on the initial EIA screen. The RPR was reactive in 150 (1.5%). TP-PA testing determined that 103 (1.0%) were falsely reactive on initial EIA screen. The reverse screening algorithm, however, identified 242 (2.4%) with evidence of latent, secondary, or past syphilis, 21 of whom had no or unknown prior treatment with antibiotics. Despite a 1.0% false-reactive rate, the reverse syphilis algorithm detected 21 patients with possible latent syphilis that may have gone undetected by traditional syphilis screening. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Re-testing and misclassification of HIV-2 and HIV-1&2 dually reactive patients among the HIV-2 cohort of The West African Database to evaluate AIDS collaboration

PubMed Central

Tchounga, Boris K; Inwoley, Andre; Coffie, Patrick A; Minta, Daouda; Messou, Eugene; Bado, Guillaume; Minga, Albert; Hawerlander, Denise; Kane, Coumba; Eholie, Serge P; Dabis, François; Ekouevi, Didier K

2014-01-01

Introduction West Africa is characterized by the circulation of HIV-1 and HIV-2. The laboratory diagnosis of these two infections as well as the choice of a first-line antiretroviral therapy (ART) is challenging, considering the limited access to second-line regimens. This study aimed at confirming the classification of HIV-2 and HIV-1&2 dually reactive patients followed up in the HIV-2 cohort of the West African Database to evaluate AIDS collaboration. Method A cross-sectional survey was conducted from March to December 2012 in Burkina Faso, Côte d’Ivoire and Mali among patients classified as HIV-2 or HIV-1&2 dually reactive according to the national HIV testing algorithms. A 5-ml blood sample was collected from each patient and tested in a single reference laboratory in Côte d’Ivoire (CeDReS, Abidjan) with two immuno-enzymatic tests: ImmunoCombII® (HIV-1&2 ImmunoComb BiSpot – Alere) and an in-house ELISA test, approved by the French National AIDS and hepatitis Research Agency (ANRS). Results A total of 547 patients were included; 57% of them were initially classified as HIV-2 and 43% as HIV-1&2 dually reactive. Half of the patients had CD4≥500 cells/mm3 and 68.6% were on ART. Of the 312 patients initially classified as HIV-2, 267 (85.7%) were confirmed as HIV-2 with ImmunoCombII® and in-house ELISA while 16 (5.1%) and 9 (2.9%) were reclassified as HIV-1 and HIV-1&2, respectively (Kappa=0.69; p<0.001). Among the 235 patients initially classified as HIV-1&2 dually reactive, only 54 (23.0%) were confirmed as dually reactive with ImmunoCombII® and in-house ELISA, while 103 (43.8%) and 33 (14.0%) were reclassified as HIV-1 and HIV-2 mono-infected, respectively (kappa= 0.70; p<0.001). Overall, 300 samples (54.8%) were concordantly classified as HIV-2, 63 (11.5%) as HIV-1&2 dually reactive and 119 (21.8%) as HIV-1 (kappa=0.79; p<0.001). The two tests gave discordant results for 65 samples (11.9%). Conclusions Patients with HIV-2 mono-infection are correctly discriminated by the national algorithms used in West African countries. HIV-1&2 dually reactive patients should be systematically investigated, with a standardized algorithm using more accurate tests, before initiating ART as at least 4 out of 10 of them could initiate an effective first-line ART for HIV-1 and optimize their second-line treatment options. PMID:25128907

EVALUATION OF PERMEABLE REACTIVE BARRIER PERFORMANCE: A TRI-AGENCY INITIATIVE

EPA Science Inventory

The permeable reactive barrier (PRB) technology represents a passive option for long-term treatment of ground-water contamination. PRBs are a potentially more cost-effective treatment option for a variety of dissolved contaminants, such as certain types of chlorinated solvents, ...

Simulations relevant to the beam instability in the foreshock

NASA Technical Reports Server (NTRS)

Cairns, I. H.; Nishikawa, K.-I.

1989-01-01

The results presently obtained from two-dimensional simulations of the reactive instability for Maxwellian beams and cutoff distributions are noted to be consistent with recent suggestions that electrons backstreaming into earth's foreshock have steep-sided cutoff distributions, which are initially unstable to the reactive instability, and that the back-reaction to the wave growth causes the instability to pass into its kinetic phase. It is demonstrated that the reactive instability is a bunching instability, and that the reactive instability saturates and passes over into the kinetic phase by particle trapping.

Evaluation of Permeable Reactive Barrier Performance

DTIC Science & Technology

2002-12-09

and-fill operation, where the trench was initially stabilized using guar gum and subsequently broken down by circulating an enzyme through the trench...80 Peerless Reactive cell placed within gravel-filled capture trench, guar gum used during installation Uranium Mill Tailings Site...Regulatory Issues 5.3.1 Biostat. The use of guar gum (a natural food thickener) as a reactive medium or as a support for trench excavation, is gaining

Characterizing redox conditions and monitoring attenuation of selected pharmaceuticals during artificial recharge through a reactive layer.

PubMed

Valhondo, Cristina; Carrera, Jesús; Ayora, Carlos; Tubau, Isabel; Martinez-Landa, Lurdes; Nödler, Karsten; Licha, Tobias

2015-04-15

A permeable reactive layer was installed at the floor of an infiltration basin. The reactive layer comprised 1) vegetable compost to provide a sorption surface for neutral organic compounds and to release easily degradable organic matter, thus generating a sequence of redox states, and 2) minor amounts of clay and iron oxide to increase sorption of cationic and anionic species, respectively. Field application of this design was successful in generating denitrification, and manganese-, and iron-reducing conditions beneath the basin. This, together with the increase in types of sorption sites, may explain the improved removal of three of the four selected pharmaceuticals compared with their behavior prior to installation of the layer. After installation of the reactive layer, atenolol concentrations were below the detection limits in the vadose zone. Moreover, concentrations of gemfibrozil and cetirizine were reduced to 20% and 40% of their initial concentrations, respectively, after 200 h of residence time. In contrast, prior to installation of the reactive layer, the concentrations of these three pharmaceuticals in both the vadose zone and the aquifer were more than 60% of the initial concentration. Carbamazepine exhibited recalcitrant behavior both prior to and after the reactive barrier installation. Copyright © 2015 Elsevier B.V. All rights reserved.

Controlling Heterogeneous Catalysis of Water Dissociation Using Cu-Ni Bimetallic Alloy Surfaces: A Quantum Dynamics Study.

PubMed

Ray, Dhiman; Ghosh, Smita; Tiwari, Ashwani Kumar

2018-06-07

Copper-Nickel bimetallic alloys are emerging heterogeneous catalysts for water dissociation which is the rate determining step of industrially important Water Gas Shift (WGS) reaction. Yet, the detailed quantum dynamics studies of water-surface scattering in literature are limited to pure metal surfaces. We present here, a three dimensional wave-packet dynamics study of water dissociation on Cu-Ni alloy surfaces, using a pseudo diatomic model of water on a London-Eyring-Polanyi-Sato (LEPS) potential energy surface in order to study the effect of initial vibration, rotation and orientation of water molecule on reactivity. For all the chosen surfaces reactivity increases significantly with vibrational excitation. In general, for lower vibrational states the reactivity increases with increasing rotational excitation but it decreases in higher vibrational states. Molecular orientation strongly affects reactivity by helping the molecule to align along the reaction path at higher vibrational states. For different alloys, the reaction probability follows the trend of barrier heights and the surfaces having all Ni atoms in the uppermost layer are much more reactive than the ones with Cu atoms. Hence the nature of the alloy surface and initial quantum state of the incoming molecule significantly influence the reactivity in surface catalyzed water dissociation.

47 CFR 69.608 - Carrier Common Line hypothetical net balance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Carrier Common Line hypothetical net balance. 69.608 Section 69.608 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER... net balance. The hypothetical net balance shall be equal to a Carrier Common Line revenue requirement...

47 CFR 69.608 - Carrier Common Line hypothetical net balance.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 3 2011-10-01 2011-10-01 false Carrier Common Line hypothetical net balance. 69.608 Section 69.608 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER... net balance. The hypothetical net balance shall be equal to a Carrier Common Line revenue requirement...

Effects of reactant rotational excitation on H + O2--> OH + O reaction rate constant: quantum wave packet, quasi-classical trajectory and phase space theory calculations.

PubMed

Lin, Shi Ying; Guo, Hua; Lendvay, György; Xie, Daiqian

2009-06-21

We examine the impact of initial rotational excitation on the reactivity of the H + O(2)--> OH + O reaction. Accurate Chebyshev wave packet calculations have been carried out for the upsilon(i) = 0, j(i) = 9 initial state of O(2) and the J = 50 partial wave. In addition, we present Gaussian-weighted quasi-classical trajectory and phase space theory calculations of the integral cross section and thermal rate constant for the title reaction. These theoretical results suggest that the initial rotational excitation significantly enhances reactivity with an amount comparable to the effect of initial vibrational state excitation. The inclusion of internally excited reactants is shown to improve the agreement with experimental rate constant.

Application of point kinetics equations to the design of a reactivity meter

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

Binney, S.E.; Bakir, A.J.M.

1988-01-01

The time-dependent reactivity of a nuclear reactor is obviously one of the most important reactor parameters that describes the state of the reactor. Although several different types of techniques exist to measure reactivity, only the kinetic method is described here. The paper illustrates the measured reactor power and calculated reactivity for a 70 cents step change in reactivity. These data were taken at 1-s time intervals. It is seen that the reactivity, initially at zero, rises rapidly to a predetermined value (determined by the reactivity change induced in the system) and then returns to zero as the reactor is reestablishedmore » in a critical situation by insertion of another control rod. It is concluded that the method of Tuttle has been adapted to produce a reliable, on-line calculation of reactivity from a time-dependent reactor power signal.« less

Reactive simulation of the chemistry behind the condensed-phase ignition of RDX from hot spots.

PubMed

Joshi, Kaushik L; Chaudhuri, Santanu

2015-07-28

Chemical events that lead to thermal initiation and spontaneous ignition of the high-pressure phase of RDX are presented using reactive molecular dynamics simulations. In order to initiate the chemistry behind thermal ignition, approximately 5% of RDX crystal is subjected to a constant temperature thermal pulse for various time durations to create a hot spot. After application of the thermal pulse, the ensuing chemical evolution of the system is monitored using reactive molecular dynamics under adiabatic conditions. Thermal pulses lasting longer than certain time durations lead to the spontaneous ignition of RDX after an incubation period. For cases where the ignition is observed, the incubation period is dominated by intermolecular and intramolecular hydrogen transfer reactions. Contrary to the widely accepted unimolecular models of initiation chemistry, N-N bond dissociations that produce NO2 species are suppressed in the condensed phase. The gradual temperature and pressure increase in the incubation period is accompanied by the accumulation of short-lived, heavier polyradicals. The polyradicals contain intact triazine rings from the RDX molecules. At certain temperatures and pressures, the polyradicals undergo ring-opening reactions, which fuel a series of rapid exothermic chemical reactions leading to a thermal runaway regime with stable gas-products such as N2, H2O and CO2. The evolution of the RDX crystal throughout the thermal initiation, incubation and thermal runaway phases observed in the reactive simulations contains a rich diversity of condensed-phase chemistry of nitramines under high-temperature/pressure conditions.

Reactivity of a Cobalt(III)–Hydroperoxo Complex in Electrophilic Reactions

DOE PAGES

Shin, Bongki; Sutherlin, Kyle D.; Ohta, Takehiro; ...

2016-11-15

The reactivity of mononuclear metal-hydroperoxo adducts has fascinated researchers in many areas due to their diverse biological and catalytic processes. In this study, a mononuclear cobalt(III)-peroxo complex bearing a tetradentate macrocyclic ligand, [Co III(Me 3-TPADP)(O 2)] + (Me 3-TPADP = 3,6,9-trimethyl-3,6,9-triaza-1(2,6)-pyridinacyclodecaphane), was prepared by reacting [Co II(Me 3-TPADP)(CH 3CN) 2] 2+ with H 2O 2 in the presence of triethylamine. Upon protonation, the cobalt(III)- peroxo intermediate was converted into a cobalt(III)-hydroperoxo complex, [Co III(Me 3-TPADP)(O 2H)(CH 3CN)] 2+. The mononuclear cobalt(III)-peroxo and -hydroperoxo intermediates were characterized by a variety of physicochemical methods. Results of electrospray ionization mass spectrometry clearly showmore » the transformation of the intermediates: the peak at m/z 339.2 assignable to the cobalt(III)-peroxo species disappears with concomitant growth of the peak at m/z 190.7 corresponding to the cobalt(III)-hydroperoxo complex (with bound CH 3CN). Isotope labeling experiments further support the existence of the cobalt(III)-peroxo and -hydroperoxo complexes. In particular, the O-O bond stretching frequency of the cobalt(III)-hydroperoxo complex was determined to be 851 cm -1 for 16O 2H samples (803 cm -1 for 18O 2H samples) and its Co-O vibrational energy was observed at 571 cm -1 for 16O 2H samples (551 cm -1 for 18O 2H samples; 568 cm -1 for 16O 2 2H samples) by resonance Raman spectroscopy. Reactivity studies performed with the cobalt(III)-peroxo and -hydroperoxo complexes in organic functionalizations reveal that the latter is capable of conducting oxygen atom transfer with an electrophilic character, whereas the former exhibits no oxygen atom transfer reactivity under the same reaction conditions. Alternatively, the cobalt(III)-hydroperoxo complex does not perform hydrogen atom transfer reactions, while analogous low-spin Fe(III)-hydroperoxo complexes are capable of this reactivity. Density function theory calculations indicate that this lack of reactivity is due to the high free energy cost of O-O bond homolysis that would be required to produce the hypothetical Co(IV)-oxo product.« less

Reactivity of a Cobalt(III)–Hydroperoxo Complex in Electrophilic Reactions

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

Shin, Bongki; Sutherlin, Kyle D.; Ohta, Takehiro

The reactivity of mononuclear metal-hydroperoxo adducts has fascinated researchers in many areas due to their diverse biological and catalytic processes. In this study, a mononuclear cobalt(III)-peroxo complex bearing a tetradentate macrocyclic ligand, [Co III(Me 3-TPADP)(O 2)] + (Me 3-TPADP = 3,6,9-trimethyl-3,6,9-triaza-1(2,6)-pyridinacyclodecaphane), was prepared by reacting [Co II(Me 3-TPADP)(CH 3CN) 2] 2+ with H 2O 2 in the presence of triethylamine. Upon protonation, the cobalt(III)- peroxo intermediate was converted into a cobalt(III)-hydroperoxo complex, [Co III(Me 3-TPADP)(O 2H)(CH 3CN)] 2+. The mononuclear cobalt(III)-peroxo and -hydroperoxo intermediates were characterized by a variety of physicochemical methods. Results of electrospray ionization mass spectrometry clearly showmore » the transformation of the intermediates: the peak at m/z 339.2 assignable to the cobalt(III)-peroxo species disappears with concomitant growth of the peak at m/z 190.7 corresponding to the cobalt(III)-hydroperoxo complex (with bound CH 3CN). Isotope labeling experiments further support the existence of the cobalt(III)-peroxo and -hydroperoxo complexes. In particular, the O-O bond stretching frequency of the cobalt(III)-hydroperoxo complex was determined to be 851 cm -1 for 16O 2H samples (803 cm -1 for 18O 2H samples) and its Co-O vibrational energy was observed at 571 cm -1 for 16O 2H samples (551 cm -1 for 18O 2H samples; 568 cm -1 for 16O 2 2H samples) by resonance Raman spectroscopy. Reactivity studies performed with the cobalt(III)-peroxo and -hydroperoxo complexes in organic functionalizations reveal that the latter is capable of conducting oxygen atom transfer with an electrophilic character, whereas the former exhibits no oxygen atom transfer reactivity under the same reaction conditions. Alternatively, the cobalt(III)-hydroperoxo complex does not perform hydrogen atom transfer reactions, while analogous low-spin Fe(III)-hydroperoxo complexes are capable of this reactivity. Density function theory calculations indicate that this lack of reactivity is due to the high free energy cost of O-O bond homolysis that would be required to produce the hypothetical Co(IV)-oxo product.« less

Enrolling adolescents in asthma research: adolescent, parent, and physician influence in the decision-making process.

PubMed

Brody, Janet L; Annett, Robert D; Scherer, David G; Turner, Charles; Dalen, Jeanne

2009-06-01

The factors influencing family decisions to participate in adolescent asthma research are not well understood. Legal and ethical imperatives require adolescent research participation to be voluntary. While parents and adolescents often agree about research decisions, disagreements may also occur with relative frequency. Physician recommendations are also known to influence research participation decisions. Little attention has been given to how these dynamics may affect adolescents' involvement in decisions to participate in research. To examine the influence of family and physician-investigator relationships and recommendations on adolescent asthma clinical research participation decisions. A statewide community sample of 111 adolescents 11 to 17 years of age, with a diagnosis of asthma, and their parents participated in this study. Adolescents received a medical evaluation from an asthma specialist and then the family was offered participation in a hypothetical asthma clinical trial. By random assignment, the research study was presented by either the same or an unknown asthma specialist, and half the families in each group also received affirmative recommendations from the asthma specialist to participate in the hypothetical asthma clinical trial. Parents and adolescents made initial private decisions about participating in the trial. Then, following a family discussion of the clinical trial, a final research participation decision was made. Thirty-three percent of parents and adolescents initially disagreed about the research participation decision. When disagreements occurred, final decisions followed the parents' initial views except when the physician-investigator was known and a recommendation was made. Families with initial disagreement about participating were less likely to enroll when the investigator was unknown or when no recommendation was made. Adolescents who initially disagreed with parents' views were less likely to concur with the final research participation decision, felt less comfortable, and were less likely to feel they influenced the decision. Parents' views on research decisions take precedence over adolescents' views in most circumstances. Physician-investigator relationships may reduce parental resistance to participation and enhance adolescent decision-making autonomy when research participation is desired by the adolescent.

Enrolling adolescents in asthma research: Adolescent, parent, and physician influence in the decision-making process

PubMed Central

Brody, Janet L.; Annett, Robert D.; Scherer, David G.; Turner, Charles; Dalen, Jeanne

2009-01-01

Background The factors influencing family decisions to participate in adolescent asthma research are not well understood. Legal and ethical imperatives require adolescent research participation to be voluntary. While parents and adolescents often agree about research decisions, disagreements may also occur with relatively frequency. Physician recommendations are also known to influence research participation decisions. Little attention has been given to how these dynamics may affect adolescents’ involvement in decisions to participate in research. Objective To examine the influence of family and physician-investigator relationships and recommendations on adolescent asthma clinical research participation decisions. Methods A statewide community sample of 111 adolescents aged 11–17, with a diagnosis of asthma, and their parents participated in this study. Adolescents received a medical evaluation from an asthma specialist and then the family was offered participation in a hypothetical asthma clinical trial. By random assignment, the research study was presented by either the same or an unknown asthma specialist and half the families in each group also received affirmative recommendations from the asthma specialist to participate in the hypothetical asthma clinical trial. Parents and adolescent made initial private decisions about participating in the trial. Then, following a family discussion of the clinical trial, a final research participation decision was made. Results Thirty three percent of parents and adolescents initially disagreed about the research participation decision. When disagreements occurred, final decisions followed the parents’ initial views except when the physician-investigator was known and a recommendation was made. Families with initial disagreement about participating were less likely to enroll when the investigator was unknown or when no recommendation was made. Adolescents who initially disagreed with parents’ views were less likely to concur with the final research participation decision, felt less comfortable, and were less likely to feel they influenced the decision. Conclusions Parents’ views on research decisions take precedence over adolescents’ views in most circumstances. Physician-investigator relationships may reduce parental resistance to participation and enhance adolescent decision-making autonomy when research participation is desired by the adolescent. PMID:19544171

Development of a three-dimensional transient code for reactivity-initiated events of BWRs (boiling water reactors) - Models and code verifications

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

Uematsu, Hitoshi; Yamamoto, Toru; Izutsu, Sadayuki

1990-06-01

A reactivity-initiated event is a design-basis accident for the safety analysis of boiling water reactors. It is defined as a rapid transient of reactor power caused by a reactivity insertion of over $1.0 due to a postulated drop or abnormal withdrawal of the control rod from the core. Strong space-dependent feedback effects are associated with the local power increase due to control rod movement. A realistic treatment of the core status in a transient by a code with a detailed core model is recommended in evaluating this event. A three-dimensional transient code, ARIES, has been developed to meet this need.more » The code simulates the event with three-dimensional neutronics, coupled with multichannel thermal hydraulics, based on a nonequilibrium separated flow model. The experimental data obtained in reactivity accident tests performed with the SPERT III-E core are used to verify the entire code, including thermal-hydraulic models.« less

Non-equilibrium reactive flux: A unified framework for slow and fast reaction kinetics.

PubMed

Bose, Amartya; Makri, Nancy

2017-10-21

The flux formulation of reaction rate theory is recast in terms of the expectation value of the reactive flux with an initial condition that corresponds to a non-equilibrium, factorized reactant density. In the common case of slow reactive processes, the non-equilibrium expression reaches the plateau regime only slightly slower than the equilibrium flux form. When the reactants are described by a single quantum state, as in the case of electron transfer reactions, the factorized reactant density describes the true initial condition of the reactive process. In such cases, the time integral of the non-equilibrium flux expression yields the reactant population as a function of time, allowing characterization of the dynamics in cases where there is no clear separation of time scales and thus a plateau regime cannot be identified. The non-equilibrium flux offers a unified approach to the kinetics of slow and fast chemical reactions and is ideally suited to mixed quantum-classical methods.

Minesweeper and Hypothetical Thinking Action Research & Pilot Study

ERIC Educational Resources Information Center

Walker, Jacob J.

2010-01-01

This Action Research project and Pilot Study was designed and implemented to improve students' hypothetical thinking abilities by exploring the possibility that learning and playing the computer game Minesweeper may inherently help improve hypothetical thinking. One objective was to use educational tools to make it easier for students to learn the…

Explaining the discrepancy between intentions and actions: the case of hypothetical bias in contingent valuation.

PubMed

Ajzen, Icek; Brown, Thomas C; Carvajal, Franklin

2004-09-01

An experiment was designed to account for intention-behavior discrepancies by applying the theory of planned behavior to contingent valuation. College students (N = 160) voted in hypothetical and real payment referenda to contribute $8 to a scholarship fund. Overestimates of willingness to pay in the hypothetical referendum could not be attributed to moderately favorable latent dispositions. Instead, this hypothetical bias was explained by activation of more favorable beliefs and attitudes in the context of a hypothetical rather than a real referendum. A corrective entreaty was found to eliminate this bias by bringing beliefs, attitudes, and intentions in line with those in the real payment situation. As a result, the theory of planned behavior produced more accurate prediction of real payment when participants were exposed to the corrective entreaty.

The impact of SOA for achieving healthcare interoperability. An empirical investigation based on a hypothetical adoption.

PubMed

Daskalakis, S; Mantas, J

2009-01-01

The evaluation of a service-oriented prototype implementation for healthcare interoperability. A prototype framework was developed, aiming to exploit the use of service-oriented architecture (SOA) concepts for achieving healthcare interoperability and to move towards a virtual patient record (VPR) paradigm. The prototype implementation was evaluated for its hypothetical adoption. The evaluation strategy was based on the initial proposition of the DeLone and McLean model of information systems (IS) success [1], as modeled by Iivari [2]. A set of SOA and VPR characteristics were empirically encapsulated within the dimensions of IS success model, combined with measures from previous research works. The data gathered was analyzed using partial least squares (PLS). The results highlighted that system quality is a partial predictor of system use but not of user satisfaction. On the contrary, information quality proved to be a significant predictor of user satisfaction and partially a strong significant predictor of system use. Moreover, system use did not prove to be a significant predictor of individual impact whereas the bi-directional relation between use and user satisfaction did not confirm. Additionally, user satisfaction was found to be a strong significant predictor of individual impact. Finally, individual impact proved to be a strong significant predictor of organizational impact. The empirical study attempted to obtain hypothetical, but still useful beliefs and perceptions regarding the SOA prototype implementation. The deduced observations can form the basis for further investigation regarding the adaptability of SOA implementations with VPR characteristics in the healthcare domain.

Feast and famine: Adipose tissue adaptations for healthy aging.

PubMed

Lettieri Barbato, Daniele; Aquilano, Katia

2016-07-01

Proper adipose tissue function controls energy balance with favourable effects on metabolic health and longevity. The molecular and metabolic asset of adipose tissue quickly and dynamically readapts in response to nutrient fluctuations. Once delivered into cells, nutrients are managed by mitochondria that represent a key bioenergetics node. A persistent nutrient overload generates mitochondrial exhaustion and uncontrolled reactive oxygen species ((mt)ROS) production. In adipocytes, metabolic/molecular reorganization is triggered culminating in the acquirement of a hypertrophic and hypersecretory phenotype that accelerates aging. Conversely, dietary regimens such as caloric restriction or time-controlled fasting endorse mitochondrial functionality and (mt)ROS-mediated signalling, thus promoting geroprotection. In this perspective view, we argued some important molecular and metabolic aspects related to adipocyte response to nutrient stress. Finally we delineated hypothetical routes by which molecularly and metabolically readapted adipose tissue promotes healthy aging. Copyright © 2016 Elsevier B.V. All rights reserved.

Reactivation of intrabasement structures during rifting: A case study from offshore southern Norway

NASA Astrophysics Data System (ADS)

Phillips, Thomas B.; Jackson, Christopher A.-L.; Bell, Rebecca E.; Duffy, Oliver B.; Fossen, Haakon

2016-10-01

Pre-existing structures within crystalline basement may exert a significant influence over the evolution of rifts. However, the exact manner in which these structures reactivate and thus their degree of influence over the overlying rift is poorly understood. Using borehole-constrained 2D and 3D seismic reflection data from offshore southern Norway we identify and constrain the three-dimensional geometry of a series of enigmatic intrabasement reflections. Through 1D waveform modelling and 3D mapping of these reflection packages, we correlate them to the onshore Caledonian thrust belt and Devonian shear zones. Based on the seismic-stratigraphic architecture of the post-basement succession, we identify several phases of reactivation of the intrabasement structures associated with multiple tectonic events. Reactivation preferentially occurs along relatively thick (c. 1 km), relatively steeply dipping (c. 30°) structures, with three main styles of interactions observed between them and overlying faults: i) faults exploiting intrabasement weaknesses represented by intra-shear zone mylonites; ii) faults that initiate within the hangingwall of the shear zones, inheriting their orientation and merging with said structure at depth; or iii) faults that initiate independently from and cross-cut intrabasement structures. We demonstrate that large-scale discrete shear zones act as a long-lived structural template for fault initiation during multiple phases of rifting.

Exploring the controls of soil biogeochemistry in a restored coastal wetland using object-oriented computer simulations of uptake kinetics and thermodynamic optimization in batch reactors

NASA Astrophysics Data System (ADS)

Payn, R. A.; Helton, A. M.; Poole, G.; Izurieta, C.; Bernhardt, E. S.; Burgin, A. J.

2012-12-01

Many hypotheses have been proposed to predict patterns of biogeochemical redox reactions based on the availability of electron donors and acceptors and the thermodynamic theory of chemistry. Our objective was to develop a computer model that would allow us to test various alternatives of these hypotheses against data gathered from soil slurry batch reactors, experimental soil perfusion cores, and in situ soil profile observations from the restored Timberlake Wetland in coastal North Carolina, USA. Software requirements to meet this objective included the ability to rapidly develop and compare different hypothetical formulations of kinetic and thermodynamic theory, and the ability to easily change the list of potential biogeochemical reactions used in the optimization scheme. For future work, we also required an object pattern that could easily be coupled with an existing soil hydrologic model. These requirements were met using Network Exchange Objects (NEO), our recently developed object-oriented distributed modeling framework that facilitates simulations of multiple interacting currencies moving through network-based systems. An initial implementation of the object pattern was developed in NEO based on maximizing growth of the microbial community from available dissolved organic carbon. We then used this implementation to build a modeling system for comparing results across multiple simulated batch reactors with varied initial solute concentrations, varied biogeochemical parameters, or varied optimization schemes. Among heterotrophic aerobic and anaerobic reactions, we have found that this model reasonably predicts the use of terminal electron acceptors in simulated batch reactors, where reactions with higher energy yields occur before reactions with lower energy yields. However, among the aerobic reactions, we have also found this model predicts dominance of chemoautotrophs (e.g., nitrifiers) when their electron donor (e.g., ammonium) is abundant, despite the fact that aerobic respiration produces a higher energy yield from the available dissolved oxygen. This suggests that incorporation of an alternative hypothesis, such as a maximum efficiency model, may be necessary to explain an observation of substantial aerobic respiration occurring in the presence of high ammonium and oxygen concentrations. We are parameterizing and testing this model based on results from batch reactor experiments that have treated soil slurries with a full factorial combination of various levels of reactive solutes found in freshwater (e.g., nitrate) and seawater (e.g., sulfate). Initial comparisons suggest that the model may need to account for the biogeochemical reactivity of iron and the potential physical influence of salt to properly describe variability in the biogeochemistry of Timberlake soils. Comparisons of these evolving models with field-derived data from soils will ultimately reveal how thermodynamic theory may be used to explain the evolution of nutrient retention and greenhouse gas emission in the Timberlake Wetland, where nutrient behavior is changing after restoration from agricultural land use and where inputs of brackish water are expected to increase due to sea level rise.

Reactivity of vinyl ethers and vinyl ribosides in UV-initiated free radical copolymerization with acceptor monomers.

PubMed

Pichavant, Loic; Guillermain, Céline; Coqueret, Xavier

2010-09-13

The reactivity of various vinyl ethers and vinyloxy derivatives of ribose in the presence of diethyl fumarate or diethyl maleate was investigated for evaluating the potential of donor-acceptor-type copolymerization applied to unsaturated monomers derived from renewable feedstock. The photochemically induced polymerization of model monomer blends in the bulk state was monitored by infrared spectroscopy. The method allowed us to examine the influence of monomer pair structure on the kinetic profiles. The simultaneous consumption of both monomers was observed, supporting an alternating copolymerization mechanism. A lower reactivity of the blends containing maleates compared with fumarates was confirmed. The obtained kinetic data revealed a general correlation between the initial polymerization rate and the Hansen parameter δ(H) associated with the H-bonding aptitude of the donor monomer.

Influences of operational practices on municipal solid waste landfill storage capacity.

PubMed

Li, Yu-Chao; Liu, Hai-Long; Cleall, Peter John; Ke, Han; Bian, Xue-Cheng

2013-03-01

The quantitative effects of three operational factors, that is initial compaction, decomposition condition and leachate level, on municipal solid waste (MSW) landfill settlement and storage capacity are investigated in this article via consideration of a hypothetical case. The implemented model for calculating landfill compression displacement is able to consider decreases in compressibility induced by biological decomposition and load dependence of decomposition compression for the MSW. According to the investigation, a significant increase in storage capacity can be achieved by intensive initial compaction, adjustment of decomposition condition and lowering of leachate levels. The quantitative investigation presented aims to encourage landfill operators to improve management to enhance storage capacity. Furthermore, improving initial compaction and creating a preferential decomposition condition can also significantly reduce operational and post-closure settlements, respectively, which helps protect leachate and gas management infrastructure and monitoring equipment in modern landfills.

LONG-TERM PERFORMANCE OF PERMEABLE REACTIVE BARRIERS: AN UPDATE ON A U.S. MULTI-AGENCY INITIATIVE

EPA Science Inventory

Permeable reactive barriers (PRB's) are an emerging, alternative in-situ approach for remediating contaminated groundwater that combine subsurface fluid flow management with a passive chemical treatment zone. PRB's are a potentially more cost effective treatment option at seve...

An assessment of adult risks of paresthesia due to mercury from coal combustion

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

Lipfert, F.; Moskowitz, P.; Fthenakis, V.

1993-11-01

This paper presents results from a probabilistic assessment of the mercury health risks associated with a hypothetical 1000 MW coal-fired power plant. The assessment draws on the extant knowledge in each of the important steps in the chain from emissions to health effects, based on methylmercury derived from seafood. For this assessment, we define three separate sources of dietary Hg: canned tuna (affected by global Hg), marine shellfish and finfish (affected by global Hg), and freshwater gamefish (affected by both global Hg and local deposition from nearby sources). We consider emissions of both reactive and elemental mercury from the hypotheticalmore » plant (assumed to burn coal with the US average Hg content) and estimate wet and dry deposition rates; atmospheric reactions are not considered. Mercury that is not deposited within 50 km is assumed to enter the global background pool. The incremental Hg in local fish is assumed to be proportional to the incremental total Hg deposition. Three alternative dose-response models were derived from published data on specific neurological responses, in this case, adult paresthesia (skin prickling or tingling of the extremities). Preliminary estimates show the upper 95th percentile of the baseline risk attributed to seafood consumption to be around 10{sup {minus}4} (1 chance in 10,000). Based on a doubling of Hg deposition in the immediate vicinity of the hypothetical plant, the incremental local risk from seafood would be about a factor of 4 higher. These risks should be compared to the estimated background prevalence rate of paresthesia, which is about 7%.« less

47 CFR 69.609 - End User Common Line hypothetical net balances.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 3 2011-10-01 2011-10-01 false End User Common Line hypothetical net balances... net balances. (a) If the company does not participate in the association tariff for such element, the hypothetical net balance shall be zero. (b) If the company does participate in the association tariff for such...

47 CFR 69.609 - End User Common Line hypothetical net balances.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false End User Common Line hypothetical net balances... net balances. (a) If the company does not participate in the association tariff for such element, the hypothetical net balance shall be zero. (b) If the company does participate in the association tariff for such...

Secreted Oral Epithelial Cell Membrane Vesicles Induce Epstein-Barr Virus Reactivation in Latently Infected B Cells

PubMed Central

Lin, Zhen; Swan, Kenneth; Zhang, Xin; Cao, Subing; Brett, Zoe; Drury, Stacy; Fewell, Claire; Puetter, Adriane; Wang, Xia; Ferris, MaryBeth; Sullivan, Deborah E.; Li, Li

2016-01-01

ABSTRACT In the oral epithelium, peripheral stores of Epstein-Barr virus (EBV) are transmitted from infiltrating B cells to epithelial cells. Once the virus is transmitted to epithelial cells, the highly permissive nature of this cell type for lytic replication allows virus amplification and exchange to other hosts. Since the initial transfer of EBV from B cells to epithelial cells requires transitioning of the B-cell to a state that induces virus reactivation, we hypothesized that there might be epithelium-specific signals that allow the infiltrating B cells to sense the appropriate environment to initiate reactivation and begin this exchange process. We previously found that the epithelium-specific miR-200 family of microRNAs promotes EBV lytic replication. Here we show that there are high levels of miR-200 family members in oral and tonsillar epithelia and in saliva. Analysis of cultured oral epithelial cells (OKF6) showed that they actively secrete membrane vesicles (exosomes) that are enriched with miR-200 family members. Coculturing of EBV-positive B cells with OKF6 cells induced viral reactivation. Further, treatment of EBV-positive B cells with OKF6 cell-derived membrane vesicles promoted reactivation. Using a cell system that does not naturally express miR-200 family members, we found that enforced expression of a miR-200 family member produced membrane vesicles that were able to induce the lytic cascade in EBV-positive B cells. We propose that membrane vesicles secreted by oral and tonsillar epithelial cells may serve as a tissue-specific environmental cue that initiates reactivation in B cells, promoting the transfer of virus from peripheral B-cell stores to the oral epithelium to facilitate virus amplification and exchange to other hosts. IMPORTANCE Epstein-Barr virus (EBV) is an important human pathogen that is causally associated with several lymphomas and carcinomas. The switch from latency to the lytic cycle is critical for successful host infection and for EBV pathogenesis. Although the EBV lytic cycle can be triggered by certain agents in vitro, the mechanisms that signal reactivation in vivo are poorly understood. We previously reported that endogenously expressed miR-200 family members likely play a role in facilitating the lytic tendencies of EBV in epithelial cells. Here we show that membrane vesicles secreted from oral epithelial cells contain miR-200 family members and that they can be transmitted to proximal EBV-positive B cells, where they trigger reactivation. We propose that this intercellular communication pathway may serve as a sensor mechanism for infiltrating B cells to recognize an appropriate environment to initiate reactivation, thereby allowing the exchange of virus to the oral epithelium. PMID:26764001

Pubertal development and regulation

PubMed Central

Abreu, Ana Paula; Kaiser, Ursula B

2016-01-01

Puberty marks the end of childhood and is a period when individuals undergo physiological and psychological changes to achieve sexual maturation and fertility. The hypothalamic-pituitary-gonadal axis controls puberty and reproduction and is tightly regulated by a complex network of excitatory and inhibitory factors. This axis is active in the embryonic and early postnatal stages of life and is subsequently restrained during childhood, and its reactivation culminates in puberty initiation. The mechanisms underlying this reactivation are not completely known. The age of puberty onset varies between individuals and the timing of puberty initiation is associated with several health outcomes in adult life. In this Series paper, we discuss pubertal markers, epidemiological trends of puberty initiation over time, and the mechanisms whereby genetic, metabolic, and other factors control secretion of gonadotropin-releasing hormone to determine initiation of puberty. PMID:26852256

LONG-TERM PERFORMANCE OF PERMEABLE REACTIVE BARRIERS TO REMEDIATE CONTAMINATED GROUND WATER

EPA Science Inventory

This research brief presents findings over the past four years at two sites where detailed investigations by the U.S. Environmental Protection Agency (U.S. EPA) have focused on the long-term performance of PRBs under a Tri-Agency Permeable Reactive Barrier Initiative (TRI). This ...

Gas Phase Reactivity of Carboxylates with N-Hydroxysuccinimide Esters

PubMed Central

Peng, Zhou; McGee, William M.; Bu, Jiexun; Barefoot, Nathan Z.; McLuckey, Scott A.

2015-01-01

N-hydroxysuccinimide (NHS) esters have been used for gas phase conjugation reactions with peptides at nucleophilic sites, such as primary amines (N-terminus, ε-amine of lysine) or guanidines, by forming amide bonds through a nucleophilic attack on the carbonyl carbon. The carboxylate has recently been found to also be a reactive nucleophile capable of initiating a similar nucleophilic attack to form a labile anhydride bond. The fragile bond is easily cleaved, resulting in an oxygen transfer from the carboxylate-containing species to the reagent, nominally observed as a water transfer. This reactivity is shown for both peptides and non-peptidic species. Reagents isotopically labeled with O18 were used to confirm reactivity. This constitutes an example of distinct differences in reactivity of carboxylates between the gas-phase, where they are shown to be reactive, and the solution-phase, where they are not regarded as reactive with NHS esters. PMID:25338221

VML 3.0 Reactive Sequencing Objects and Matrix Math Operations for Attitude Profiling

NASA Technical Reports Server (NTRS)

Grasso, Christopher A.; Riedel, Joseph E.

2012-01-01

VML (Virtual Machine Language) has been used as the sequencing flight software on over a dozen JPL deep-space missions, most recently flying on GRAIL and JUNO. In conjunction with the NASA SBIR entitled "Reactive Rendezvous and Docking Sequencer", VML version 3.0 has been enhanced to include object-oriented element organization, built-in queuing operations, and sophisticated matrix / vector operations. These improvements allow VML scripts to easily perform much of the work that formerly would have required a great deal of expensive flight software development to realize. Autonomous turning and tracking makes considerable use of new VML features. Profiles generated by flight software are managed using object-oriented VML data constructs executed in discrete time by the VML flight software. VML vector and matrix operations provide the ability to calculate and supply quaternions to the attitude controller flight software which produces torque requests. Using VML-based attitude planning components eliminates flight software development effort, and reduces corresponding costs. In addition, the direct management of the quaternions allows turning and tracking to be tied in with sophisticated high-level VML state machines. These state machines provide autonomous management of spacecraft operations during critical tasks like a hypothetic Mars sample return rendezvous and docking. State machines created for autonomous science observations can also use this sort of attitude planning system, allowing heightened autonomy levels to reduce operations costs. VML state machines cannot be considered merely sequences - they are reactive logic constructs capable of autonomous decision making within a well-defined domain. The state machine approach enabled by VML 3.0 is progressing toward flight capability with a wide array of applicable mission activities.

Computer simulation of wolf-removal strategies for animal-damage control

USGS Publications Warehouse

Haight, R.G.; Travis, L.E.; Nimerfro, K.; Mech, L.D.

2002-01-01

Because of the sustained growth of the gray wolf (Canis lupus) population in the western Great Lakes region of the United States, management agencies are anticipating gray wolf removal from the federal endangered species list and are proposing strategies for wolf management. Strategies are needed that would balance public demand for wolf conservation with demand for protection against wolf depredation on livestock, poultry, and pets. We used a stochastic, spatially structured, individually based simulation model of a hypothetical wolf population, representing a small subset of the western Great Lakes wolves, to predict the relative performance of 3 wolf-removal strategies. Those strategies included reactive management (wolf removal occurred in summer after depredation), preventive management (wolves removed in winter from territories with occasional depredation), and population-size management (wolves removed annually in winter from all territories near farms). Performance measures included number of depredating packs and wolves removed, cost, and population size after 20 years. We evaluated various scenarios about immigration, trapping success, and likelihood of packs engaging in depredation. Four robust results emerged from the simulations: 1) each strategy reduced depredation by at least 40% compared with no action, 2) preventive and population-size management removed fewer wolves than reactive management because wolves were removed in winter before pups were born, 3)population-size management was least expensive because repeated annual removal kept most territories near farms free of wolves, and 4) none of the strategies threatened wolf populations unless they were isolated because wolf removal took place near farms and not in wild areas. For isolated populations, reactive management alone ensured conservation and reduced depredation. Such results can assist decision makers in managing gray wolves in the western Great Lakes states.

High-sensitive factor I and C-reactive protein based biomarkers for coronary artery disease.

PubMed

Zhao, Qing; Du, Jian-Shi; Han, Dong-Mei; Ma, Ying

2014-01-01

An analysis of high-sensitive factor I and C-reactive proteins as biomarkers for coronary artery disease has been performed from 19 anticipated cohort studies that included 21,567 participants having no information about coronary artery disease. Besides, the clinical implications of statin therapy initiated due to assessment of factor I and C-reactive proteins have also been modeled during studies. The measure of risk discrimination (C-index) was increased (by 0.0101) as per the prognostic model for coronary artery disease with respect to sex, smoking status, age, blood pressure, total cholesterol level along with diabetic history characteristic parameters. The C-index was further raised by 0.0045 and 0.0053 when factor I and C-reactive proteins based information were added, respectively which finally predicted 10-year risk categories as: high (> 20%), medium (10% to < 20%), and low (< 10%) risks. We found 2,254 persons (among 15,000 adults (age ≥ 45 years)) would initially be classified as being at medium risk for coronary artery disease when only conventional risk factors were used as calculated risk. Besides, persons with a predicted risk of more than 20% as well as for persons suffering from other risk factors (i.e. diabetes), statin therapy was initiated (irrespective of their decade old predicted risk). We conclude that under current treatment guidelines assessment of factor I and C-reactive proteins levels (as biomarker) in people at medium risk for coronary artery disease could prevent one additional coronary artery disease risk over a period a decade for every 390-500 people screened.

Initial characterization of an Experimental Referee Broadened-Specification (ERBS) aviation turbine fuel

NASA Technical Reports Server (NTRS)

Prok, G. M.; Seng, G. T.

1980-01-01

Characterization data and a hydrocarbon compositional analysis are presented for a research test fuel designated as an experimental referee broadened-specification aviation turbine fuel. This research fuel, which is a special blend of kerosene and hydrotreated catalytic gas oil, is a hypothetical representation of a future fuel should it become necessary to broaden current kerojet specifications. It is used as a reference fuel in research investigations into the effects of fuel property variations on the performance and durability of jet aircraft components, including combustors and fuel systems.

Distributed coding of actual and hypothetical outcomes in the orbital and dorsolateral prefrontal cortex

PubMed Central

Abe, Hiroshi; Lee, Daeyeol

2011-01-01

SUMMARY Knowledge about hypothetical outcomes from unchosen actions is beneficial only when such outcomes can be correctly attributed to specific actions. Here, we show that during a simulated rock-paper-scissors game, rhesus monkeys can adjust their choice behaviors according to both actual and hypothetical outcomes from their chosen and unchosen actions, respectively. In addition, neurons in both dorsolateral prefrontal cortex and orbitofrontal cortex encoded the signals related to actual and hypothetical outcomes immediately after they were revealed to the animal. Moreover, compared to the neurons in the orbitofrontal cortex, those in the dorsolateral prefrontal cortex were more likely to change their activity according to the hypothetical outcomes from specific actions. Conjunctive and parallel coding of multiple actions and their outcomes in the prefrontal cortex might enhance the efficiency of reinforcement learning and also contribute to their context-dependent memory. PMID:21609828

Total Synthesis of (±)–Rocaglamide via Oxidation-Initiated Nazarov Cyclization

PubMed Central

Malona, John A.; Cariou, Kevin; Spencer, William T.

2012-01-01

This article describes the evolution of a Nazarov cyclization-based synthetic strategy targeting the anticancer, antiinflammatory, and insecticidal natural product (±)–rocaglamide. Initial pursuit of a polarized heteroaromatic Nazarov cyclization to construct the congested cyclopentane core revealed an unanticipated electronic bias in the pentadienyl cation. This reactivity was harnessed in a successful second-generation approach using an oxidation-initiated Nazarov cyclization of a heteroaryl alkoxyallene. Full details of these two approaches are given, as well as the characterization of undesired reaction pathways available to the Nazarov cyclization product. A sequence of experiments that led to an understanding of the unexpected reactivity of this key intermediate is described, which culminated in the successful total synthesis of (+)-rocaglamide. PMID:22283818

DIETARY BAKED EGG ACCELERATES RESOLUTION OF EGG ALLERGY IN CHILDREN

PubMed Central

Leonard, Stephanie A.; Sampson, Hugh A.; Sicherer, Scott H.; Noone, Sally; Moshier, Erin L.; Godbold, James; Nowak-Wȩgrzyn, Anna

2012-01-01

Background Baked egg is tolerated by a majority of egg-allergic children. Objective To characterize immunologic changes associated with ingestion of baked egg and evaluate the role that baked egg diets plays in the development of tolerance to regular egg. Methods Egg-allergic subjects who tolerated baked egg challenge incorporated baked egg into their diet. Immunologic parameters were measured at follow-up visits. A comparison group strictly avoiding egg was used to evaluate the natural history of the development of tolerance. Results Of the 79 subjects in the intent-to-treat group followed for a median of 37.8 months, 89% now tolerate baked egg and 53% now tolerate regular egg. Of 23 initial baked egg-reactive subjects, 14 (61%) subsequently tolerated baked egg and 6 (26%) now tolerate regular egg. Within the initially baked egg-reactive group, subjects with persistent reactivity to baked egg had higher median baseline egg white (EW)-specific IgE levels (13.5 kUA/L) than those who subsequently tolerated baked egg (4.4 kUA/L; P=0.04) and regular egg (3.1 kUA/L, P=0.05). In subjects ingesting baked egg, EW-induced SPT wheal diameter and EW-, ovalbumin-, and ovomucoid-specific IgE levels decreased significantly, while ovalbumin- and ovomucoid-specific IgG4 levels increased significantly. Subjects in the per-protocol group were 14.6 times more likely to develop regular egg tolerance than subjects in the comparison group (P < 0.0001), and they developed tolerance earlier (median 50.0 versus 78.7 months; P<0.0001). Conclusion Initiation of a baked egg diet accelerates the development of regular egg tolerance compared to strict avoidance. Higher serum EW-specific IgE level is associated with persistent baked and regular egg reactivity, while initial baked egg reactivity is not. PMID:22846751

Dietary baked egg accelerates resolution of egg allergy in children.

PubMed

Leonard, Stephanie A; Sampson, Hugh A; Sicherer, Scott H; Noone, Sally; Moshier, Erin L; Godbold, James; Nowak-Węgrzyn, Anna

2012-08-01

Baked egg is tolerated by a majority of egg-allergic children. To characterize immunologic changes associated with ingestion of baked egg and evaluate the role that baked egg diets play in the development of tolerance to regular egg. Egg-allergic subjects who tolerated baked egg challenge incorporated baked egg into their diet. Immunologic parameters were measured at follow-up visits. A comparison group strictly avoiding egg was used to evaluate the natural history of the development of tolerance. Of the 79 subjects in the intent-to-treat group followed for a median of 37.8 months, 89% now tolerate baked egg and 53% now tolerate regular egg. Of 23 initially baked egg-reactive subjects, 14 (61%) subsequently tolerated baked egg and 6 (26%) now tolerate regular egg. Within the initially baked egg-reactive group, subjects with persistent reactivity to baked egg had higher median baseline egg white (EW)-specific IgE levels (13.5 kU(A)/L) than those who subsequently tolerated baked egg (4.4 kU(A)/L; P= .04) and regular egg (3.1 kU(A)/L; P= .05). In subjects ingesting baked egg, EW-induced skin prick test wheal diameter and EW-, ovalbumin-, and ovomucoid-specific IgE levels decreased significantly, while ovalbumin- and ovomucoid-specific IgG(4) levels increased significantly. Subjects in the per-protocol group were 14.6 times more likely than subjects in the comparison group (P< .0001) to develop regular egg tolerance, and they developed tolerance earlier (median 50.0 vs 78.7 months; P< .0001). Initiation of a baked egg diet accelerates the development of regular egg tolerance compared with strict avoidance. Higher serum EW-specific IgE level is associated with persistent baked and regular egg reactivity, while initial baked egg reactivity is not. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Measurement of Reactive Oxygen Species, Reactive Nitrogen Species, and Redox-Dependent Signaling in the Cardiovascular System

PubMed Central

Griendling, Kathy K.; Touyz, Rhian M.; Zweier, Jay L.; Dikalov, Sergey; Chilian, William; Chen, Yeong-Renn; Harrison, David G.; Bhatnagar, Aruni

2017-01-01

Reactive oxygen species and reactive nitrogen species are biological molecules that play important roles in cardiovascular physiology and contribute to disease initiation, progression, and severity. Because of their ephemeral nature and rapid reactivity, these species are difficult to measure directly with high accuracy and precision. In this statement, we review current methods for measuring these species and the secondary products they generate and suggest approaches for measuring redox status, oxidative stress, and the production of individual reactive oxygen and nitrogen species. We discuss the strengths and limitations of different methods and the relative specificity and suitability of these methods for measuring the concentrations of reactive oxygen and reactive nitrogen species in cells, tissues, and biological fluids. We provide specific guidelines, through expert opinion, for choosing reliable and reproducible assays for different experimental and clinical situations. These guidelines are intended to help investigators and clinical researchers avoid experimental error and ensure high-quality measurements of these important biological species. PMID:27418630

Testing the effectiveness of certainty scales, cheap talk, and dissonance-minimization in reducing hypothetical bias in contingent valuation studies

Treesearch

Mark Morrison; Thomas C. Brown

2009-01-01

Stated preference methods such as contingent valuation and choice modeling are subject to various biases that may lead to differences between actual and hypothetical willingness to pay. Cheap talk, follow-up certainty scales, and dissonance minimization are three techniques for reducing this hypothetical bias. Cheap talk and certainty scales have received considerable...

Explaining the discrepancy between intentions and actions: the case of hypothetical bias in contingent valuation

Treesearch

Icek Ajzen; Thomas C. Brown; Franklin Carvajal

2004-01-01

An experiment was designed to account for intention-behavior discrepancies by applying the theory of planned behavior to contingent valuation. College students (N = 160) voted in hypothetical and real payment referenda to contribute $8 to a scholarship fund. Overestimates of willingness to pay in the hypothetical referendum could not be attributed to moderately...

Is Silence Golden? Elementary School Teachers' Strategies and Beliefs regarding Hypothetical Shy/Quiet and Exuberant/Talkative Children

ERIC Educational Resources Information Center

Coplan, Robert J.; Hughes, Kathleen; Bosacki, Sandra; Rose-Krasnor, Linda

2011-01-01

The primary goal of the present study was to examine elementary teachers' strategies, attitudes, and beliefs regarding hypothetical shy (i.e., quiet), exuberant (i.e., overly talkative), and average (i.e., typical) children. We explored whether these strategies and beliefs varied as a function of the gender of the hypothetical child as well as…

Using respondent uncertainty to mitigate hypothetical bias in a stated choice experiment

Treesearch

Richard C. Ready; Patricia A. Champ; Jennifer L. Lawton

2010-01-01

In a choice experiment study, willingness to pay for a public good estimated from hypothetical choices was three times as large as willingness to pay estimated from choices requiring actual payment. This hypothetical bias was related to the stated level of certainty of respondents. We develop protocols to measure respondent certainty in the context of a choice...

Predictors of anticipatory cortisol reactivity to subsequent stressors.

PubMed

Turan, Bulent

2015-10-01

Understanding the nature, predictors, and consequences of anticipatory biological stress responses are important in understanding long-term effects of repeated stressors. We examined anticipatory cortisol responses after an individual has actually experienced and reacted to a stressor once and is anticipating a second similar stressor. We hypothesized that how an individual reacts to the first stressor may predict that individual's anticipatory responses to further stressors. In Session 1, 77 male participants delivered speeches and performed arithmetic tasks in front of two evaluators. In Session 2 one week later, participants were told that they would do the same tasks again in front of evaluators. Stress cortisol reactivity in Session 1 (increase in cortisol from pre-stressor to post-stressor) predicted anticipatory cortisol reactivity in Session 2 (increase in cortisol from baseline to immediately pre-stressor). In addition, trait measures of low self-esteem and a "Submissive and Disconnected" interpersonal orientation predicted stronger anticipatory cortisol reactivity in Session 2. If the cortisol response to an initial stressor does in fact shape consequent anticipatory cortisol responses, this self-perpetuating nature of the initial cortisol response may contribute to negative long-term effects of repeated stressors on health. One factor that may be able to counteract this effect is a dominant and confident interpersonal orientation, which may lead to lower anticipatory cortisol reactions regardless of the response to the initial stressor. Copyright © 2015 Elsevier Inc. All rights reserved.

FT-IR, FT-Raman and NMR characterization of 2-isopropyl-5-methylcyclohexyl quinoline-2-carboxylate and investigation of its reactive and optoelectronic properties by molecular dynamics simulations and DFT calculations

NASA Astrophysics Data System (ADS)

Menon, Vidya V.; Fazal, Edakot; Mary, Y. Sheena; Panicker, C. Yohannan; Armaković, Stevan; Armaković, Sanja J.; Nagarajan, Subban; Van Alsenoy, C.

2017-01-01

The FT-IR and FT-Raman spectra of the synthesized compound, 2-isopropyl-5-methylcyclohexyl quinoline-2-carboxylate is recorded and analyzed. Optimized molecular structure, wave numbers, corresponding assignments regarding 2-isopropyl-5-methylcyclohexyl quinoline-2-carboxylate has become screened tentatively as well as hypothetically using Gaussian09 program package. Natural bonding orbital assessment has been completed with a reason to clarify charge transfer or conjugative interaction, the intra-molecular re-hybridization and delocalization of electron density within the molecule. The NMR spectral assessment had been made choosing structure property relationship by chemical shifts along with the magnetic shielding effects regarding the title compound. The first and second hyperpolarizabilities were calculated. The calculated first order hyperpolarizability is commensurate with the documented worth of very similar derivatives and could be an interesting object for more experiments on nonlinear optics. Local reactivity properties have been investigated using average local ionization energies and Fukui functions. Investigation of optoelectronic properties encompassed calculations of reorganization energies and hopping rates of charge carriers within the framework of Marcus semi-empiric approach. The docked ligand title compound forms a stable complex with CDK inhibitors and gives a binding affinity value of -9.7 kcal/mol and molecular docking results suggest that the compound might exhibit inhibitory activity against CDK inhibitors.

Memory consolidation by replay of stimulus-specific neural activity.

PubMed

Deuker, Lorena; Olligs, Jan; Fell, Juergen; Kranz, Thorsten A; Mormann, Florian; Montag, Christian; Reuter, Martin; Elger, Christian E; Axmacher, Nikolai

2013-12-04

Memory consolidation transforms initially labile memory traces into more stable representations. One putative mechanism for consolidation is the reactivation of memory traces after their initial encoding during subsequent sleep or waking state. However, it is still unknown whether consolidation of individual memory contents relies on reactivation of stimulus-specific neural representations in humans. Investigating stimulus-specific representations in humans is particularly difficult, but potentially feasible using multivariate pattern classification analysis (MVPA). Here, we show in healthy human participants that stimulus-specific activation patterns can indeed be identified with MVPA, that these patterns reoccur spontaneously during postlearning resting periods and sleep, and that the frequency of reactivation predicts subsequent memory for individual items. We conducted a paired-associate learning task with items and spatial positions and extracted stimulus-specific activity patterns by MVPA in a simultaneous electroencephalography and functional magnetic resonance imaging (fMRI) study. As a first step, we investigated the amount of fMRI volumes during rest that resembled either one of the items shown before or one of the items shown as a control after the resting period. Reactivations during both awake resting state and sleep predicted subsequent memory. These data are first evidence that spontaneous reactivation of stimulus-specific activity patterns during resting state can be investigated using MVPA. They show that reactivation occurs in humans and is behaviorally relevant for stabilizing memory traces against interference. They move beyond previous studies because replay was investigated on the level of individual stimuli and because reactivations were not evoked by sensory cues but occurred spontaneously.

Combination of photocatalytic and membrane distillation hybrid processes for reactive dyes treatment.

PubMed

Yatmaz, H Cengiz; Dizge, Nadir; Kurt, Merve Sezen

2017-11-01

In this study, the degradation of azo dye solutions (Reactive Red 180 and Reactive Orange 16) of textile industry wastewater was investigated for using innovative hybrid process of photocatalytic and membrane distillation (MD) processes. Photocatalytic oxidation was conducted with semiconductor catalysts (ZnO and TiO2) and their mixture under UVA and UVC irradiation. More effective results were obtained under UVA at the initial stages of the reactions for both dye solutions. ZnO and TiO2 catalysts have given similar efficient results, but results with ZnO were better at initial stages. For the next stage, hybrid design of MD and photocatalytic processes was performed sequentially. Initially, the photocatalytic process was conducted for at least 1 h at initial values of 100 mg/L RR-180 dye solutions and 1 g/L ZnO catalyst loading under UVA irradiation and then treated solution was run through the distillation module at different temperatures (30°C and 40°C) and flow rates (210, 425, and 665 mL/min). Three types of membranes (polypropylene, polytetrafluoroethylene, and polyvinylidene fluoride) with different pore sizes (0.45 and 0.22 μm) were used in the module. Increasing temperature on the side of treated solution and decreasing the temperature on the other side has increased the distillate efficiency.

In Situ Biogeochemical Treatment Demonstration: Lessons Learned from ESTCP Project ER 201124

DTIC Science & Technology

2015-12-09

vegetable oil fermentation to volatile fatty acids (VFA) also likely reduced the pH and this change could have reduced the FeS reactivity. 2.3.5...Initially about 6.5 ● Vegetable oil fermentation to VFAs ● Lower FeSx reactivity Need to balance iron and sulfur! 55 Critical Factors

Remaking Memories: Reconsolidation Updates Positively Motivated Spatial Memory in Rats

ERIC Educational Resources Information Center

Jones, Bethany; Bukoski, Elizabeth; Nadel, Lynn; Fellous, Jean-Marc

2012-01-01

There is strong evidence that reactivation of a memory returns it to a labile state, initiating a restabilization process termed reconsolidation, which allows for updating of the memory. In this study we investigated reactivation-dependent updating using a new positively motivated spatial task in rodents that was designed specifically to model a…

Conceptual design of quadriso particles with europium burnable absorber in HTRS.

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

Talamo, A.; Nuclear Engineering Division

2010-05-18

In High Temperature Reactors, burnable absorbers are utilized to manage the excess reactivity at the early stage of the fuel cycle. In this study QUADRISO particles are proposed to manage the initial xcess reactivity of High Temperature Reactors. The QUADRISO concept synergistically couples the decrease of the burnable poison with the decrease of the fissile materials at the fuel particle level. This echanism is set up by introducing a burnable poison layer around the fuel kernel in ordinary TRISO particles or by mixing the burnable poison with any of the TRISO coated layers. At the beginning of life, the nitialmore » excess reactivity is small because some neutrons are absorbed in the burnable poison and they are prevented from entering the fuel kernel. At the end of life, when the absorber is almost depleted, ore eutrons stream into the fuel kernel of QUADRISO particles causing fission reactions. The mechanism has been applied to a prismatic High Temperature Reactor with europium or erbium burnable absorbers, showing a significant reduction in the initial excess reactivity of the core.« less

Reactivity-based drug discovery using vitamin B(6)-derived pharmacophores.

PubMed

Wondrak, Georg T

2008-05-01

Endogenous reactive intermediates including photoexcited states of tissue chromophores, reactive oxygen species (ROS), reactive carbonyl species (RCS), transition metal ions, and Schiff bases have been implicated in the initiation and progression of diverse human pathologies including tumorigenesis, atherosclerosis, diabetes, and neurodegenerative disease. In contrast to structure-based approaches that target macromolecules by selective ligands, reactivity-based drug discovery uses chemical reagents as therapeutics that target reactive chemical species involved in human pathology. Reactivity-based design of prototype agents that effectively antagonize, modulate, and potentially even reverse the chemistry underlying tissue damage from oxidative and carbonyl stress therefore holds great promise in delivering significant therapeutic benefit. Apart from its established role as an essential cofactor for numerous enzymes, a large body of evidence suggests that B(6)-vitamers contain reactive pharmacophores that mediate therapeutically useful non-vitamin drug actions as potent antioxidants, metal chelators, carbonyl scavengers, Schiff base forming agents, and photosensitizers. Based on the fascinating chemical versatility of B(6)-derived pharmacophores, B(6)-vitamers are therefore promising lead compounds for reactivity-based drug design.

Patterning of Thick Parylene Films by Oxygen Plasma for Application as Exploding Foil Initiator Flyer Material

DTIC Science & Technology

2009-09-01

exploding foil initiator ( EFI ) type fuzes are being explored to...Acronyms Au gold Cr chromium Cu copper EFI exploding foil initiator BOE buffered oxide etch MEMS microelectromechanical systems RIE reactive ion...Patterning of Thick Parylene Films by Oxygen Plasma for Application as Exploding Foil Initiator Flyer Material by Eugene Zakar and Michael

A cost analysis in patients with acute coronary syndrome using clopidogrel in addition to aspirin in a Hong Kong public hospital.

PubMed

Lee, Vivian W Y; Chan, Wai Kwong; Lee, Kenneth K C

2006-09-01

Results from the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) study showed that clopidogrel plus aspirin, compared to aspirin alone, reduced cardiovascular events (death, myocardial infarction, and stroke) in patients with acute coronary syndromes (ACS). Yet the acquisition cost of clopidogrel is much higher. It would therefore be worthwhile to compare the long-term cost impact of these 2 regimens. Until recently, only very few patients with ACS received clopidogrel-aspirin combination therapy in Hong Kong. Therefore, a hypothetical cohort was formed and compared to a real group of patients treated with aspirin alone. For the aspirin group, medical history was reviewed and cardiovascular and gastrointestinal events occurring in a period of 12 months after initiation of therapy were recorded. The target cost items included hospitalisation, emergency room visits, outpatient clinic visits, related medications, diagnostic tests, procedures, and surgery. For the hypothetical cohort, the probabilities/relative risks for clinical events were adopted from the CURE study. Fifty-four consecutive patients with ACS receiving aspirin therapy were identified and studied between January 1, 2001 and December 31, 2001 from a major public hospital in Hong Kong. The average cost of management per patient over the 12 month period for the aspirin group was HK$85,324 (US$10,940, HK$7.8 = 1 US$) versus the hypothetical cohort HK$83,903 (US$10,757). Hospitalisation represented the major cost item (64.6%), followed by the cost of investigational tests (14.5%) and procedural cost (11.6%). According to our analytical model, the overall cost impact between clopidogrel plus aspirin versus aspirin alone in the 2 groups of patients was similar.

Numerical Hydrodynamic Study of Hypothetical Levee Setback Scenarios

DTIC Science & Technology

2018-01-01

ER D C /C HL T R- 18 -1 Flood and Coastal Systems Research and Development Program Numerical Hydrodynamic Study of Hypothetical Levee...default. Flood and Coastal Systems Research and Development Program ERDC/CHL TR-18-1 January 2018 Numerical Hydrodynamic Study of Hypothetical...Reduction” ERDC/CHL TR-18-1 ii Abstract A numerical hydrodynamic study was conducted to compare multiple levee setback alternatives to the base

Assessing reactivation of the Pourewa Landslide Zone, Auckland, New Zealand, using Structure-from-Motion, LiDAR, and geophysics

NASA Astrophysics Data System (ADS)

Brook, Martin; Liu, Shanshan; Richards, Nick; Bevan, David; Prebble, Warwick

2017-04-01

Landslides pose significant risks to communities and infrastructure particularly in urban areas, and mitigating these risks relies on understanding landslide triggering processes that may cause reactivation. Previous work has shown that landslides are often complex, multiphase processes where gradual deterioration of shear strength within the subsurface precedes slope failure and the appearance of surface morphological features. Here, we combine a suite of remote sensing and direct invasive testing techniques to assess reactivation of the Pourewa Landslide Zone (PLZ), located in Auckland, New Zealand. The PLZ is located on the inner wall of the north-eastern flank of the Orakei volcano, 4 km east of Auckland CBD. The landslide zone occupies slopes above the east bank of the tidal Pourewa Creek, which lies within a residential area. Four landslides are located within the PLZ (from west to east): Ngapipi Road Landslide, Kepa Road Landslide, St Josephs Landslide, and Pourewa Landslide. Inward collapse of the crater walls since the initial eruption (>85 ka) has enlarged the crater to c. 1000 m diameter, with some slopes prone to ongoing mass movements. Indeed, reactivation during the 20th century led to the realignment of Kepa Road, and surface cracking of roads in the vicinity is ongoing. LiDAR imagery was used to develop high resolution geomorphological maps, and this data was compared with more recent Structure-from-Motion (SfM) photogrammetry, obtained from an unmanned aerial vehicle (UAV). The digital surface models and derived cross-sections developed from these data allow both the initial failure, and subsequent reactivations to be assessed in detail. Geophysical surveys included Electromagnetic Induction (EMI), augmented by information relating to lithological, moisture and strength variation with depth, allowing initial interpretation of zones likely to be prone to reactivation. Ongoing slope deformation includes shallow, retrogressive failure on the upper slopes, and translation and flow toward the toe. Taken together, results indicate that reactivation is strongly controlled by lithology, as well as porewater pressure. The study highlights the value of a combined geophysical and direct testing approach for landslide hazard assessment in order to mitigate risk to infrastructure.

HIV testing of pregnant women: an ethical analysis.

PubMed

Johansson, Kjell Arne; Pedersen, Kirsten Bjerkreim; Andersson, Anna-Karin

2011-12-01

Recent global advances in available technology to prevent mother-to-child HIV transmission necessitate a rethinking of contemporary and previous ethical debates on HIV testing as a means to preventing vertical transmission. In this paper, we will provide an ethical analysis of HIV-testing strategies of pregnant women. First, we argue that provider-initiated opt-out HIV testing seems to be the most effective HIV test strategy. The flip-side of an opt-out strategy is that it may end up as involuntary testing in a clinical setting. We analyse this ethical puzzle from a novel perspective, taking into account the moral importance of certain hypothetical preferences of the child, as well as the moral importance of certain actual preferences of the mother. Finally, we balance the conflicting concerns and try to arrive at an ethically sound solution to this dilemma. Our aim is to introduce a novel perspective from which to analyse testing strategies, and to explore the implications and possible benefits of our proposal. The conclusion from our analysis is that policies that recommend provider-initiated opt-out HIV testing of pregnant mothers, with a risk of becoming involuntary testing in a clinical setting, are acceptable. The rationale behind this is that the increased availability of very effective and inexpensive life-saving drugs makes the ethical problems raised by the possible intrusiveness of HIV testing less important than the child's hypothetical preferences to be born healthy. Health care providers, therefore, have a duty to offer both opt-out HIV testing and available PMTCT (preventing mother-to-child transmission) interventions. © 2011 Blackwell Publishing Ltd.

Solar System Chaos and Orbital Solutions for Paleoclimate Studies: Limits and New Results

NASA Astrophysics Data System (ADS)

Zeebe, R. E.

2017-12-01

I report results from accurate numerical integrations of Solar System orbits over the past 100 Myr. The simulations used different integrator algorithms, step sizes, and initial conditions (NASA, INPOP), and included effects from general relativity, different models of the Moon, the Sun's quadrupole moment, and up to ten asteroids. In one simulation, I probed the potential effect of a hypothetical Planet 9 on the dynamics of the system. The most expensive integration required 4 months wall-clock time (Bulirsch-Stoer algorithm) and showed a maximum relative energy error < 2.5e{-13} over the past 100 Myr. The difference in Earth's eccentricity (DeE) was used to track the difference between two solutions, which were considered to diverge at time tau when DeE irreversibly crossed 10% of Earth's mean eccentricity ( 0.028 x 0.1). My results indicate that finding a unique orbital solution is limited by initial conditions from current ephemerides to 54 Myr. Bizarrely, the 4-month Bulirsch-Stoer integration and a different integration scheme that required only 5 hours wall-clock time (symplectic, 12-day time step, Moon as a simple quadrupole perturbation), agree to 63 Myr. Solutions including 3 and 10 asteroids diverge at tau 48 Myr. The effect of a hypothetical Planet 9 on DeE becomes discernible at 66 Myr. Using tau as a criterion, the current state-of-the-art solutions all differ from previously published results beyond 50 Myr. The current study provides new orbital solutions for application in geological studies. I will also comment on the prospect of constraining astronomical solutions by geologic data.

Cardiovascular reactivity to video game predicts subsequent blood pressure increases in young men: The CARDIA study.

PubMed

Markovitz, J H; Raczynski, J M; Wallace, D; Chettur, V; Chesney, M A

1998-01-01

This study was undertaken to determine the relationship between heightened reactivity of blood pressure (BP) during stress and 5-year changes in blood pressure and hypertensive status, using the CARDIA study. A total of 3364 participants (910 white men, 909 white women, 678 black men, and 867 black women), initially 20 to 32 years old and normotensive, were included. Cardiovascular reactivity to psychological stressors (video game and star-tracing tasks for 3 minutes, cold pressor test for 1 minute) was measured in 1987-1988. We then examined reactivity as a predictor of significant BP change (> or = 8 mm Hg, thought to represent a clinically significant increase) over the next 5 years. Logistic regression models were used to control for potential covariates. Significant BP change and the development of hypertension (BP greater than 140/90 or taking medication for hypertension) over the 5-year follow-up were examined in separate analyses. Increased systolic blood pressure (SBP) reactivity to the video game was associated with a significant 5-year SBP increase among the entire cohort, independent of resting SBP (p < .0001). Subsequent analyses showed that this relationship held for men but not for women. Reactivity to the star-tracing task or the cold pressor test did not predict significant BP change. Among black men only, new hypertensives (N = 36) had greater diastolic blood pressure (DBP) reactivity to the video game (p = .01). Although BP reactivity to all physical and mental stressors used in this study did not consistently predict 5-year change in BP in this young cohort, the results indicate that reactivity to a video game stressor predicts 5-year change in BP and early hypertension among young adult men. These findings are consistent with other studies showing the usefulness of stressors producing a primarily beta-adrenergic response in predicting BP change and hypertension. The results may be limited by the shortened initial rest and recovery periods used in the CARDIA protocol.

Reductive reactivity of iron(III) oxides in the east china sea sediments: characterization by selective extraction and kinetic dissolution.

PubMed

Chen, Liang-Jin; Zhu, Mao-Xu; Yang, Gui-Peng; Huang, Xiang-Li

2013-01-01

Reactive Fe(III) oxides in gravity-core sediments collected from the East China Sea inner shelf were quantified by using three selective extractions (acidic hydroxylamine, acidic oxalate, bicarbonate-citrate buffered sodium dithionite). Also the reactivity of Fe(III) oxides in the sediments was characterized by kinetic dissolution using ascorbic acid as reductant at pH 3.0 and 7.5 in combination with the reactive continuum model. Three parameters derived from the kinetic method: m 0 (theoretical initial amount of ascorbate-reducible Fe(III) oxides), k' (rate constant) and γ (heterogeneity of reactivity), enable a quantitative characterization of Fe(III) oxide reactivity in a standardized way. Amorphous Fe(III) oxides quantified by acidic hydroxylamine extraction were quickly consumed in the uppermost layer during early diagenesis but were not depleted over the upper 100 cm depth. The total amounts of amorphous and poorly crystalline Fe(III) oxides are highly available for efficient buffering of dissolved sulfide. As indicated by the m 0, k' and γ, the surface sediments always have the maximum content, reactivity and heterogeneity of reactive Fe(III) oxides, while the three parameters simultaneously downcore decrease, much more quickly in the upper layer than at depth. Albeit being within a small range (within one order of magnitude) of the initial rates among sediments at different depths, incongruent dissolution could result in huge discrepancies of the later dissolution rates due to differentiating heterogeneity, which cannot be revealed by selective extraction. A strong linear correlation of the m 0 at pH 3.0 with the dithionite-extractable Fe(III) suggests that the m 0 may represent Fe(III) oxide assemblages spanning amorphous and crystalline Fe(III) oxides. Maximum microbially available Fe(III) predicted by the m 0 at pH 7.5 may include both amorphous and a fraction of other less reactive Fe(III) phases.

Reductive Reactivity of Iron(III) Oxides in the East China Sea Sediments: Characterization by Selective Extraction and Kinetic Dissolution

PubMed Central

Chen, Liang-Jin; Zhu, Mao-Xu; Yang, Gui-Peng; Huang, Xiang-Li

2013-01-01

Reactive Fe(III) oxides in gravity-core sediments collected from the East China Sea inner shelf were quantified by using three selective extractions (acidic hydroxylamine, acidic oxalate, bicarbonate-citrate buffered sodium dithionite). Also the reactivity of Fe(III) oxides in the sediments was characterized by kinetic dissolution using ascorbic acid as reductant at pH 3.0 and 7.5 in combination with the reactive continuum model. Three parameters derived from the kinetic method: m 0 (theoretical initial amount of ascorbate-reducible Fe(III) oxides), k′ (rate constant) and γ (heterogeneity of reactivity), enable a quantitative characterization of Fe(III) oxide reactivity in a standardized way. Amorphous Fe(III) oxides quantified by acidic hydroxylamine extraction were quickly consumed in the uppermost layer during early diagenesis but were not depleted over the upper 100 cm depth. The total amounts of amorphous and poorly crystalline Fe(III) oxides are highly available for efficient buffering of dissolved sulfide. As indicated by the m 0, k′ and γ, the surface sediments always have the maximum content, reactivity and heterogeneity of reactive Fe(III) oxides, while the three parameters simultaneously downcore decrease, much more quickly in the upper layer than at depth. Albeit being within a small range (within one order of magnitude) of the initial rates among sediments at different depths, incongruent dissolution could result in huge discrepancies of the later dissolution rates due to differentiating heterogeneity, which cannot be revealed by selective extraction. A strong linear correlation of the m 0 at pH 3.0 with the dithionite-extractable Fe(III) suggests that the m 0 may represent Fe(III) oxide assemblages spanning amorphous and crystalline Fe(III) oxides. Maximum microbially available Fe(III) predicted by the m 0 at pH 7.5 may include both amorphous and a fraction of other less reactive Fe(III) phases. PMID:24260377

Glucocorticoid Programing of the Mesopontine Cholinergic System

PubMed Central

Borges, Sónia; Coimbra, Bárbara; Soares-Cunha, Carina; Ventura-Silva, Ana P.; Pinto, Luisa; Carvalho, Miguel M.; Pêgo, José-Miguel; Rodrigues, Ana João; Sousa, Nuno

2013-01-01

Stress perception, response, adaptation, and coping strategies are individually distinct, and the sequel of stress and/or glucocorticoids (GCs) is also distinct between subjects. In the last years, it has become clear that early life stress is a powerful modulator of neuroendocrine stress-responsive circuits, programing intrinsic susceptibility to stress, and potentiating the appearance of stress-related disorders such as depression, anxiety, and addiction. Herein we were interested in understanding how early life experiences reset the normal processing of negative stimuli, leading to emotional dysfunction. Animals prenatally exposed to GCs (in utero glucocorticoid exposure, iuGC) present hyperanxiety, increased fear behavior, and hyper-reactivity to negative stimuli. In parallel, we found a remarkable increase in the number of aversive 22 kHz ultrasonic vocalizations in response to an aversive cue. Considering the suggested role of the mesopontine tegmentum cholinergic pathway, arising from the laterodorsal tegmental nucleus (LDT) and pedunculopontine tegmental nucleus (PPT), in the initiation of 22 kHz vocalizations and hypothetically in the control of emotional arousal and tone, we decided to evaluate the condition of this circuit in iuGC animals. Notably, in a basal situation, iuGC animals present increased choline acetyltransferase (ChAT) expression in the LDT and PPT, but not in other cholinergic nuclei, namely in the nucleus basalis of Meynert. In addition, and in accordance with the amplified response to an adverse stimulus of iuGC animals, we found marked changes in the cholinergic activation pattern of LDT and PPT regions. Altogether, our results suggest a specific cholinergic pathway programing by prenatal GC, and hint that this may be of relevance in setting individual stress vulnerability threshold. PMID:24379803

Permeability generation and resetting of tracers during metamorphic fluid flow: implications for advection-dispersion models

NASA Astrophysics Data System (ADS)

Cartwright, Ian

Advection-dispersion fluid flow models implicitly assume that the infiltrating fluid flows through an already fluid-saturated medium. However, whether rocks contain a fluid depends on their reaction history, and whether any initial fluid escapes. The behaviour of different rocks may be illustrated using hypothetical marble compositions. Marbles with diverse chemistries (e.g. calcite + dolomite + quartz) are relatively reactive, and will generally produce a fluid during heating. By contrast, marbles with more restricted chemistries (e.g. calcite + quartz or calcite-only) may not. If the rock is not fluid bearing when fluid infiltration commences, mineralogical reactions may produce a reaction-enhanced permeability in calcite + dolomite + quartz or calcite + quartz, but not in calcite-only marbles. The permeability production controls the pattern of mineralogical, isotopic, and geochemical resetting during fluid flow. Tracers retarded behind the mineralogical fronts will probably be reset as predicted by the advection-dispersion models; however, tracers that are expected to be reset ahead of the mineralogical fronts cannot progress beyond the permeability generating reaction. In the case of very unreactive lithologies (e.g. pure calcite marbles, cherts, and quartzites), the first reaction to affect the rocks may be a metasomatic one ahead of which there is little pervasive resetting of any tracer. Centimetre-scale layering may lead to the formation of self-perpetuating fluid channels in rocks that are not fluid saturated due to the juxtaposition of reactants. Such layered rocks may show patterns of mineralogical resetting that are not predicted by advection-dispersion models. Patterns of mineralogical and isotopic resetting in marbles from a number of terrains, for example: Chillagoe, Marulan South, Reynolds Range (Australia); Adirondack Mountains, Old Woman Mountains, Notch Peak (USA); and Stephen Cross Quarry (Canada) vary as predicted by these models.

Photoluminescent silicon nanocrystals with chlorosilane surfaces - synthesis and reactivity

NASA Astrophysics Data System (ADS)

Höhlein, Ignaz M. D.; Kehrle, Julian; Purkait, Tapas K.; Veinot, Jonathan G. C.; Rieger, Bernhard

2014-12-01

We present a new efficient two-step method to covalently functionalize hydride terminated silicon nanocrystals with nucleophiles. First a reactive chlorosilane layer was formed via diazonium salt initiated hydrosilylation of chlorodimethyl(vinyl)silane which was then reacted with alcohols, silanols and organolithium reagents. With organolithium compounds a side reaction is observed in which a direct functionalization of the silicon surface takes place.We present a new efficient two-step method to covalently functionalize hydride terminated silicon nanocrystals with nucleophiles. First a reactive chlorosilane layer was formed via diazonium salt initiated hydrosilylation of chlorodimethyl(vinyl)silane which was then reacted with alcohols, silanols and organolithium reagents. With organolithium compounds a side reaction is observed in which a direct functionalization of the silicon surface takes place. Electronic supplementary information (ESI) available: Detailed experimental procedures and additional NMR, PL, EDX, DLS and TEM data. See DOI: 10.1039/C4NR05888G

The initiation of lateral roots in the primary roots of maize (Zea mays L.) implies a reactivation of cell proliferation in a group of founder pericycle cells.

PubMed

Alarcón, M Victoria; Lloret, Pedro G; Martín-Partido, Gervasio; Salguero, Julio

2016-03-15

The initiation of lateral roots (LRs) has generally been viewed as a reactivation of proliferative activity in pericycle cells that are committed to initiate primordia. However, it is also possible that pericycle founder cells that initiate LRs never cease proliferative activity but rather are displaced to the most distal root zones while undertaking successive stages of LR initiation. In this study, we tested these two alternative hypotheses by examining the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into the DNA of meristematic root cells of Zea mays. According to the values for the length of the cell cycle and values for cell displacement along the maize root, our results strongly suggest that pericycle cells that initiate LR primordia ceased proliferative activity upon exiting the meristematic zone. This finding is supported by the existence of a root zone between 4 and 20mm from the root cap junction, in which neither mitotic cells nor labelled nuclei were observed in phloem pericycle cells. Copyright © 2016 Elsevier GmbH. All rights reserved.

Coaggregation-Mediated Interactions of Streptococci and Actinomyces Detected in Initial Human Dental Plaque

PubMed Central

Palmer, Jr., Robert J.; Gordon, Sharon M.; Cisar, John O.; Kolenbrander, Paul E.

2003-01-01

Streptococci and actinomyces that initiate colonization of the tooth surface frequently coaggregate with each other as well as with other oral bacteria. These observations have led to the hypothesis that interbacterial adhesion influences spatiotemporal development of plaque. To assess the role of such interactions in oral biofilm formation in vivo, antibodies directed against bacterial surface components that mediate coaggregation interactions were used as direct immunofluorescent probes in conjunction with laser confocal microscopy to determine the distribution and spatial arrangement of bacteria within intact human plaque formed on retrievable enamel chips. In intrageneric coaggregation, streptococci such as Streptococcus gordonii DL1 recognize receptor polysaccharides (RPS) borne on other streptococci such as Streptococcus oralis 34. To define potentially interactive subsets of streptococci in the developing plaque, an antibody against RPS (anti-RPS) was used together with an antibody against S. gordonii DL1 (anti-DL1). These antibodies reacted primarily with single cells in 4-h-old plaque and with mixed-species microcolonies in 8-h-old plaque. Anti-RPS-reactive bacteria frequently formed microcolonies with anti-DL1-reactive bacteria and with other bacteria distinguished by general nucleic acid stains. In intergeneric coaggregation between streptococci and actinomyces, type 2 fimbriae of actinomyces recognize RPS on the streptococci. Cells reactive with antibody against type 2 fimbriae of Actinomyces naeslundii T14V (anti-type-2) were much less frequent than either subset of streptococci. However, bacteria reactive with anti-type-2 were seen in intimate association with anti-RPS-reactive cells. These results are the first direct demonstration of coaggregation-mediated interactions during initial plaque accumulation in vivo. Further, these results demonstrate the spatiotemporal development and prevalence of mixed-species communities in early dental plaque. PMID:12754239

Differences in Behavior and Brain Activity during Hypothetical and Real Choices.

PubMed

Camerer, Colin; Mobbs, Dean

2017-01-01

Real behaviors are binding consequential commitments to a course of action, such as harming another person, buying an Apple watch, or fleeing from danger. Cognitive scientists are generally interested in the psychological and neural processes that cause such real behavior. However, for practical reasons, many scientific studies measure behavior using only hypothetical or imagined stimuli. Generalizing from such studies to real behavior implicitly assumes that the processes underlying the two types of behavior are similar. We review evidence of similarity and differences in hypothetical and real mental processes. In many cases, hypothetical choice tasks give an incomplete picture of brain circuitry that is active during real choice. Copyright © 2016. Published by Elsevier Ltd.

Regulation of cambial activity in relation to environmental conditions: understanding the role of temperature in wood formation of trees.

PubMed

Begum, Shahanara; Nakaba, Satoshi; Yamagishi, Yusuke; Oribe, Yuichiro; Funada, Ryo

2013-01-01

The timing of cambial reactivation plays an important role in determination of the amount and quality of wood and the environmental adaptivity of trees. Environmental factors, such as temperature, influence the growth and development of trees. Temperatures from late winter to early spring affect the physiological processes that are involved in the initiation of cambial cell division and xylem differentiation in trees. Cumulative elevated temperatures from late winter to early spring result in earlier initiation of cambial reactivation and xylem differentiation in tree stems and an extended growth period. However, earlier cambial reactivation increases the risk for frost damage because the cold tolerance of cambium decreases after cambial reactivation. The present review focuses on temperature regulation on the timing of cambial reactivation and xylem differentiation in trees, and also highlights recent advances in our understanding of seasonal changes in the cold stability of microtubules in trees. The review also summarizes the present understanding of the relationships between the timing of cambial reactivation, the start of xylem differentiation and changes in levels of storage materials in trees, as well as an attempt to identify the source of energy for cell division and differentiation. A better understanding of the mechanisms that regulate wood formation in trees and the influence of environmental conditions on such mechanisms should help in efforts to improve and enhance the exploitation of wood for commercial applications and to prepare for climatic change. Copyright © Physiologia Plantarum 2012.

Reaction Mechanism of Covalent Modification of Phosphatidylethanolamine Lipids by Reactive Aldehydes 4-Hydroxy-2-nonenal and 4-Oxo-2-nonenal.

PubMed

Vazdar, Katarina; Vojta, Danijela; Margetić, Davor; Vazdar, Mario

2017-03-20

4-Hydroxy-2-nonenal (HNE) and 4-oxo-2-nonenal (ONE) are biologically important reactive aldehydes formed during oxidative stress in phospholipid bilayers. They are highly reactive species due to presence of several reaction centers and can react with amino acids in peptides and proteins, as well as phosphoethanolamine (PE) lipids, thus modifying their biological activity. The aim of this work is to study in a molecular detail the reactivity of HNE and ONE toward PE lipids in a simplified system containing only lipids and reactive aldehydes in dichloromethane as an inert solvent. We use a combination of quantum chemical calculations, 1 H NMR measurements, FT-IR spectroscopy, and mass spectrometry experiments and show that for both reactive aldehydes two types of chemical reactions are possible: formation of Michael adducts and Schiff bases. In the case of HNE, an initially formed Michael adduct can also undergo an additional cyclization step to a hemiacetal derivative, whereas no cyclization occurs in the case of ONE and a Michael adduct is identified. A Schiff base product initially formed when HNE is added to PE lipid can also further cyclize to a pyrrole derivative in contrast to ONE, where only a Schiff base product is isolated. The suggested reaction mechanism by quantum-chemical calculations is in a qualitative agreement with experimental yields of isolated products and is also additionally investigated by 1 H NMR measurements, FT-IR spectroscopy, and mass spectrometry experiments.

Quantification of pathogen inactivation efficacy by free chlorine disinfection of drinking water for QMRA.

PubMed

Petterson, S R; Stenström, T A

2015-09-01

To support the implementation of quantitative microbial risk assessment (QMRA) for managing infectious risks associated with drinking water systems, a simple modeling approach for quantifying Log10 reduction across a free chlorine disinfection contactor was developed. The study was undertaken in three stages: firstly, review of the laboratory studies published in the literature; secondly, development of a conceptual approach to apply the laboratory studies to full-scale conditions; and finally implementation of the calculations for a hypothetical case study system. The developed model explicitly accounted for variability in residence time and pathogen specific chlorine sensitivity. Survival functions were constructed for a range of pathogens relying on the upper bound of the reported data transformed to a common metric. The application of the model within a hypothetical case study demonstrated the importance of accounting for variable residence time in QMRA. While the overall Log10 reduction may appear high, small parcels of water with short residence time can compromise the overall performance of the barrier. While theoretically simple, the approach presented is of great value for undertaking an initial assessment of a full-scale disinfection contactor based on limited site-specific information.

Differential neural circuitry and self-interest in real vs hypothetical moral decisions

PubMed Central

Dalgleish, Tim; Thompson, Russell; Evans, Davy; Schweizer, Susanne; Mobbs, Dean

2012-01-01

Classic social psychology studies demonstrate that people can behave in ways that contradict their intentions—especially within the moral domain. We measured brain activity while subjects decided between financial self-benefit (earning money) and preventing physical harm (applying an electric shock) to a confederate under both real and hypothetical conditions. We found a shared neural network associated with empathic concern for both types of decisions. However, hypothetical and real moral decisions also recruited distinct neural circuitry: hypothetical moral decisions mapped closely onto the imagination network, while real moral decisions elicited activity in the bilateral amygdala and anterior cingulate—areas essential for social and affective processes. Moreover, during real moral decision-making, distinct regions of the prefrontal cortex (PFC) determined whether subjects make selfish or pro-social moral choices. Together, these results reveal not only differential neural mechanisms for real and hypothetical moral decisions but also that the nature of real moral decisions can be predicted by dissociable networks within the PFC. PMID:22711879

A workplace breast cancer screening program. Costs and components.

PubMed

Schrammel, P; Griffiths, R I; Griffiths, C B

1998-11-01

Screening for breast cancer can result in early detection of malignancies and lives saved. Many employers now offer periodic screening as an employee health benefit, and some have established screening programs in the workplace. This study was performed to identify the employer costs of breast cancer screening in the workplace, referrals for suspicious findings, and initial treatment of malignant disease. Additionally, the costs for these same services, had they been obtained outside of a workplace screening program, were estimated. Data on program components and associated costs for an established employer based breast cancer screening program were obtained. These costs were compared to those among a hypothetical cohort of women not enrolled in the workplace screening program. From 1989 through 1995, 1,416 women participated in the program. Nearly 2,500 screening mammograms and approximately 2,773 clinical breast examinations were performed, resulting in 292 referrals to physicians outside of the program for additional diagnostic procedures and treatment as needed. These referrals resulted in the detection of 12 malignancies: 8 Stage I; 3 Stage II; and 1 Stage III. Mammographic and clinical breast examination screening cost $249,041; referrals resulting in benign disease or no detectable disease cost $185,002; and referrals resulting in malignant disease, followed by initial treatment, cost $148,530. Therefore, the total cost was $582,573. Approximately 47% of the cost of referrals and initial treatment were due to employee lost productivity. Total cost in the hypothetical cohort was $1,067,948 under the assumptions that all women received screening outside of the workplace, and that the same number of malignancies were detected at the same stage as in the workplace program. These findings indicate referrals resulting in detection of benign disease or no disease accounted for a substantial proportion of the total cost of the program. In addition, employee lost productivity accounted for almost 50% of the cost of all referrals and initial treatment. Workplace screening is a relatively efficient approach for early detection of breast cancer when compared to off site screening or no screening. The efficiency could be improved with a reduction in the number and cost of unnecessary referrals.

Hemorrhagic Cystitis due to BK Reactivation in a Young Female Treated for Hodgkin-Disease.

PubMed

Le Calloch, R; Ianotto, J C; Berthou, C; Tempescul, A

2011-01-01

Hodgkin's lymphoma is a disease with a high rate of curability under classic chemo-radiotherapy regimes. Complications due to chemotherapy could include viral reactivation due to chronic lymphopenia. BK virus (BKV) is a polyoma virus belonging to the Papovaviridae family with antibody seroprevalences in healthy populations varying from 60% to 80%. Initial infections are asymptomatic usually occur in early childhood, after which the viruses remain latent in the kidneys or urothelium. Reactivation of BKV occurs in individuals with severe immunosuppression during HIV infections, transplantation or, exceptionally, after classical chemotherapy. BKV incidence is approximately 0% to 5% in immunocompetent individuals. Reactivation is associated with nephropathy and haemorrhagic cystitis. Herein, we present a case of a haemorrhagic cystitis due to BKV reactivation in a patient with Hodgkin's disease treated with chemotherapy.

Take Me Out to the Ballgame, but Keep Me away from the Concession Stand Workers: A Hypothetical Case Involving Negligent Volunteers at Ballparks

ERIC Educational Resources Information Center

Thor, Jennifer Cordon; York, Kenneth M.

2016-01-01

The hypothetical case presented in this article challenges students in a legal environment of business course to answer that question by examining key legal concepts in agency and contract law, and to conduct an ethical analysis in a case involving volunteers. Although the events in the following case are hypothetical, the contract that the…

Further evidence of close correspondence for alcohol demand decision making for hypothetical and incentivized rewards.

PubMed

Amlung, Michael; MacKillop, James

2015-04-01

Alcohol purchase tasks (APTs) are increasingly being used to assess behavioral economic demand for alcohol. Prior studies utilizing APTs have typically assessed demand for hypothetical outcomes, making the extent to which these hypothetical measures reflect preferences when actual rewards are at stake an important empirical question. This study examined alcohol demand across hypothetical and incentivized APTs. Nineteen male heavy drinkers completed two APTs - one for hypothetical alcohol and another in which one randomly-selected outcome was provided. Participants were given an opportunity to consume the alcohol associated with their choice on the incentivized APT during a self-administration period in a simulated bar environment. Results indicated generally close correspondence between APT versions, though participants were more sensitive to increases in price and tended to consume more at low prices on the incentivized version. Estimated consumption on the incentivized APT was highly correlated with the amount of alcohol consumed in the laboratory (r=.87, p<.001), suggesting that APT responses are valid indicators of actual drinking behavior. These results provide further evidence of congruence of demand-based decision-making when rewards are hypothetical vs. actually available. Implications for behavioral economic approaches to addictive behavior and directions for future research are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

40 CFR 63.4541 - How do I demonstrate initial compliance with the emission limitations?

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR... volatile matter and use that value as a substitute for mass fraction of organic HAP. For reactive adhesives... not have to count it. For reactive adhesives in which some of the HAP react to form solids and are not...

40 CFR 63.3941 - How do I demonstrate initial compliance with the emission limitations?

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR... organic HAP. For reactive adhesives in which some of the HAP react to form solids and are not emitted to... reactive adhesives in which some of the HAP react to form solids and are not emitted to the atmosphere, you...

40 CFR 63.4551 - How do I demonstrate initial compliance with the emission limitations?

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR... organic HAP in coating, i, kg organic HAP per kg coating. For reactive adhesives as defined in § 63.4581... reactive adhesives as defined in § 63.4581, use the mass fraction of organic HAP that is emitted as...

40 CFR 63.3951 - How do I demonstrate initial compliance with the emission limitations?

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR... coating. For reactive adhesives as defined in § 63.3981, use the mass fraction of organic HAP that is... organic HAP per kg thinner and/or other additive. For reactive adhesives as defined in § 63.3981, use the...

Laccase and its role in production of extracellular reactive oxygen species during wood decay by the brown rot basidiomycete Postia placenta

Treesearch

Dongsheng Wei; Carl J. Houtman; Alexander N. Kapich; Christopher G. Hunt; Daniel Cullen; Kenneth E. Hammel

2010-01-01

Brown rot basidiomycetes initiate wood decay by producing extracellular reactive oxygen species that depolymerize the structural polysaccharides of lignocellulose. Secreted fungal hydroquinones are considered one contributor because they have been shown to reduce Fe3+, thus generating perhydroxyl radicals and Fe2+, which...

Grafting of Bacterial Polyhydroxybutyrate (PHB) onto Cellulose via In Situ Reactive Extrusion with Dicumyl Peroxide

Treesearch

Liqing Wei; Armando G. McDonald; Nicole M. Stark

2015-01-01

Polyhydroxybutyrate (PHB) was grafted onto cellulose fiber by dicumyl peroxide (DCP) radical initiation via in situ reactive extrusion. The yield of the grafted (cellulose-g-PHB) copolymer was recorded and grafting efficiency was found to be dependent on the reaction time and DCP concentration. The grafting mechanism was investigated by electron spin...

Learning to integrate reactivity and deliberation in uncertain planning and scheduling problems

NASA Technical Reports Server (NTRS)

Chien, Steve A.; Gervasio, Melinda T.; Dejong, Gerald F.

1992-01-01

This paper describes an approach to planning and scheduling in uncertain domains. In this approach, a system divides a task on a goal by goal basis into reactive and deliberative components. Initially, a task is handled entirely reactively. When failures occur, the system changes the reactive/deliverative goal division by moving goals into the deliberative component. Because our approach attempts to minimize the number of deliberative goals, we call our approach Minimal Deliberation (MD). Because MD allows goals to be treated reactively, it gains some of the advantages of reactive systems: computational efficiency, the ability to deal with noise and non-deterministic effects, and the ability to take advantage of unforseen opportunities. However, because MD can fall back upon deliberation, it can also provide some of the guarantees of classical planning, such as the ability to deal with complex goal interactions. This paper describes the Minimal Deliberation approach to integrating reactivity and deliberation and describe an ongoing application of the approach to an uncertain planning and scheduling domain.

Cue-independent memory impairment by reactivation-coupled interference in human declarative memory.

PubMed

Zhu, Zijian; Wang, Yingying; Cao, Zhijun; Chen, Biqing; Cai, Huaqian; Wu, Yanhong; Rao, Yi

2016-10-01

Memory is a dynamic process. While memory becomes increasingly resistant to interference after consolidation, a brief reactivation renders it unstable again. Previous studies have shown that interference, when applied upon reactivation, impairs the consolidated memory, presumably by disrupting the reconsolidation of the memory. However, attempts have failed in disrupting human declarative memory, raising a question about whether declarative memory becomes unstable upon reactivation. Here, we used a double-cue/one-target paradigm, which associated the same target with two different cues in initial memory formation. Only one cue/target association was later reactivated and treated with behavioral interference. Our results showed, for the first time, that reactivation-coupled interference caused cue-independent memory impairment that generalized to other cues associated with the memory. Critically, such memory impairment appeared immediately after interference, before the reconsolidation process was completed, suggesting that common manipulations of reactivation-coupled interference procedures might disrupt other processes in addition to the reconsolidation process in human declarative memory. Copyright © 2016. Published by Elsevier B.V.

How different terminology for ductal carcinoma in situ impacts women's concern and treatment preferences: a randomised comparison within a national community survey

PubMed Central

McCaffery, Kirsten; Nickel, Brooke; Moynihan, Ray; Hersch, Jolyn; Teixeira-Pinto, Armando; Irwig, Les; Barratt, Alexandra

2015-01-01

Objective There have been calls to remove ‘carcinoma’ from terminology for in situ cancers such as ductal carcinoma in situ (DCIS), to reduce overdiagnosis and overtreatment. We investigated the effect of describing DCIS as ‘abnormal cells’ versus ‘pre-invasive breast cancer cells’ on women's concern and treatment preferences. Setting and participants Community sample of Australian women (n=269) who spoke English as their main language at home. Design Randomised comparison within a community survey. Women considered a hypothetical scenario involving a diagnosis of DCIS described as either ‘abnormal cells’ (arm A) or ‘pre-invasive breast cancer cells’ (arm B). Within each arm, the initial description was followed by the alternative term and outcomes reassessed. Results Women in both arms indicated high concern, but still indicated strong initial preferences for watchful waiting (64%). There were no differences in initial concern or preferences by trial arm. However, more women in arm A (‘abnormal cells’ first term) indicated they would feel more concerned if given the alternative term (‘pre-invasive breast cancer cells’) compared to women in arm B who received the terms in the opposite order (67% arm A vs 52% arm B would feel more concerned, p=0.001). More women in arm A also changed their preference towards treatment when the terminology was switched from ‘abnormal cells’ to ‘pre-invasive breast cancer cells’ compared to arm B. In arm A, 18% of women changed their preference to treatment while only 6% changed to watchful waiting (p=0.008). In contrast, there were no significant changes in treatment preference in arm B when the terminology was switched (9% vs 8% changed their stated preference). Conclusions In a hypothetical scenario, interest in watchful waiting for DCIS was high, and changing terminology impacted women's concern and treatment preferences. Removal of the cancer term from DCIS may assist in efforts towards reducing overtreatment. PMID:26525720

Behavioral Economics of Cigarette Purchase Tasks: Within-Subject Comparison of Real, Potentially Real, and Hypothetical Cigarettes

PubMed Central

Wilson, A. George; Franck, Christopher T.; Koffarnus, Mikhail N.

2016-01-01

Abstract Introduction: Hypothetical rewards are commonly used in studies of laboratory-based tobacco demand. However, behavioral economic demand procedures require confirmation that the behavior elicited from real and hypothetical reward types are equivalent, and that results attained from these procedures are comparable to other accepted tasks, such as the hypothetical purchase task. Methods: Nineteen smokers were asked to purchase 1 week’s worth of cigarettes that they would consume over the following week either at one price that incrementally increased across four weekly sessions (“real” sessions) or four prices in a single session (“potentially real” session), one of which was randomly chosen to be actualized. At each session, participants also completed a hypothetical cigarette purchase task. After each week, participants reported the number of cigarettes they actually smoked. Results: Demand was found to be equivalent under both the real and potentially real reward conditions but statistically different from the demand captured in the hypothetical purchase task. However, the amounts purchased at specific prices in the hypothetical purchase task were significantly correlated with the amount purchased at comparable prices in the other two tasks (except for the highest price examined in both tasks of $1.00 per cigarette). Number of cigarettes consumed that were obtained outside of the study was correlated with study cigarette price. Conclusions: Combined, these results suggest that purchasing behavior during potentially real sessions (1) was not functionally different from real sessions, (2) imposes fewer costs to the experimenter, and (3) has high levels of both internal and external validity. PMID:26187389

The Boehringer Ingelheim employee study (Part 2): 10-year cardiovascular diseases risk estimation.

PubMed

Kempf, K; Martin, S; Döhring, C; Dugi, K; Haastert, B; Schneider, M

2016-10-01

Cardiovascular disease (CVD) may cause an economic burden to companies, but CVD risk estimations specific to working populations are lacking. To estimate the 10-year CVD risk in the Boehringer Ingelheim (BI) employee cohort and analyse the potential effect of hypothetical risk reduction interventions. We estimated CVD risk using the Framingham (FRS), PROCAM (PRS) and Reynolds (RRS) risk scores, using cross-sectional baseline data on BI Pharma employees collected from 2005 to 2011. Results were compared using Fisher's exact and Wilcoxon tests. The predictive ability of the score estimates was assessed using receiver-operating characteristics analyses. Among the 4005 study subjects, we estimated 10-year CVD risks of 35% (FRS), 9% (PRS) and 6% (RRS) for men and 10% (FRS), 4% (PRS) and 1% (RRS) for women. One hundred and thirty-four (6%) men and 111 (6%) women employees had current CVD. The best predictors of prevalent CVD were the FRS and the RRS for men [area-under-the-curve 0.62 (0.57-0.67) for both]. A hypothetical intervention that would improve systolic blood pressure, HbA1c (for diabetes), C-reactive protein, triglycerides and total and high-density lipoprotein cholesterol by 10% each would potentially reduce expected CVD cases by 36-41% in men and 30-45% in women, and if smoking cessation is incorporated, by 39-45% and 30-55%, respectively, depending on the pre-intervention risk score. There was a substantial risk of developing CVD in this working cohort. Occupational health programmes with lifestyle interventions for high-risk individuals may be an effective risk reduction measure. © The Author 2016. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Three Hypothetical Inflammation Pathobiology Phenotypes and Pediatric Sepsis-Induced Multiple Organ Failure Outcome.

PubMed

Carcillo, Joseph A; Halstead, E Scott; Hall, Mark W; Nguyen, Trung C; Reeder, Ron; Aneja, Rajesh; Shakoory, Bita; Simon, Dennis

2017-06-01

We hypothesize that three inflammation pathobiology phenotypes are associated with increased inflammation, proclivity to develop features of macrophage activation syndrome, and multiple organ failure-related death in pediatric severe sepsis. Prospective cohort study comparing children with severe sepsis and any of three phenotypes: 1) immunoparalysis-associated multiple organ failure (whole blood ex vivo tumor necrosis factor response to endotoxin < 200 pg/mL), 2) thrombocytopenia-associated multiple organ failure (new onset thrombocytopenia with acute kidney injury and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 activity < 57%), and/or 3) sequential multiple organ failure with hepatobiliary dysfunction (respiratory distress followed by liver dysfunction with soluble Fas ligand > 200 pg/mL), to those without any of these phenotypes. Tertiary children's hospital PICU. One hundred consecutive severe sepsis admissions. Clinical data were recorded daily, and blood was collected twice weekly. Multiple organ failure developed in 75 cases and eight died. Multiple organ failure cases with any of the three inflammation phenotypes (n = 37) had higher inflammation (C-reactive protein, p = 0.009 and ferritin, p < 0.001) than multiple organ failure cases without any of these phenotypes (n = 38) or cases with only single organ failure (n = 25). Development of features of macrophage activation syndrome and death were more common among multiple organ failure cases with any of the phenotypes (macrophage activation syndrome: 10/37, 27%; death: 8/37, 22%) compared to multiple organ failure cases without any phenotype (macrophage activation syndrome: 1/38, 3%; p = 0.003 and death: 0/38, 0%; p = 0.002). Our approach to phenotype categorization remains hypothetical, and the phenotypes identified need to be confirmed in multicenter studies of pediatric multiple organ dysfunction syndrome.

Measurement of Reactive Oxygen Species, Reactive Nitrogen Species, and Redox-Dependent Signaling in the Cardiovascular System: A Scientific Statement From the American Heart Association.

PubMed

Griendling, Kathy K; Touyz, Rhian M; Zweier, Jay L; Dikalov, Sergey; Chilian, William; Chen, Yeong-Renn; Harrison, David G; Bhatnagar, Aruni

2016-08-19

Reactive oxygen species and reactive nitrogen species are biological molecules that play important roles in cardiovascular physiology and contribute to disease initiation, progression, and severity. Because of their ephemeral nature and rapid reactivity, these species are difficult to measure directly with high accuracy and precision. In this statement, we review current methods for measuring these species and the secondary products they generate and suggest approaches for measuring redox status, oxidative stress, and the production of individual reactive oxygen and nitrogen species. We discuss the strengths and limitations of different methods and the relative specificity and suitability of these methods for measuring the concentrations of reactive oxygen and reactive nitrogen species in cells, tissues, and biological fluids. We provide specific guidelines, through expert opinion, for choosing reliable and reproducible assays for different experimental and clinical situations. These guidelines are intended to help investigators and clinical researchers avoid experimental error and ensure high-quality measurements of these important biological species. © 2016 American Heart Association, Inc.

Inhibition of Epstein-Barr virus reactivation by the flavonoid apigenin.

PubMed

Wu, Chung-Chun; Fang, Chih-Yeu; Cheng, Yu-Jhen; Hsu, Hui-Yu; Chou, Sheng-Ping; Huang, Sheng-Yen; Tsai, Ching-Hwa; Chen, Jen-Yang

2017-01-05

Lytic reactivation of EBV has been reported to play an important role in human diseases, including NPC carcinogenesis. Inhibition of EBV reactivation is considered to be of great benefit in the treatment of virus-associated diseases. For this purpose, we screened for inhibitory compounds and found that apigenin, a flavonoid, seemed to have the ability to inhibit EBV reactivation. We performed western blotting, immunofluorescence and luciferase analyses to determine whether apigenin has anti-EBV activity. Apigenin inhibited expression of the EBV lytic proteins, Zta, Rta, EAD and DNase in epithelial and B cells. It also reduced the number of EBV-reactivating cells detectable by immunofluorescence analysis. In addition, apigenin has been found to reduce dramatically the production of EBV virions. Luciferase reporter analysis was performed to determine the mechanism by which apigenin inhibits EBV reactivation: apigenin suppressed the activity of the immediate-early (IE) gene Zta and Rta promoters, suggesting it can block initiation of the EBV lytic cycle. Taken together, apigenin inhibits EBV reactivation by suppressing the promoter activities of two viral IE genes, suggesting apigenin is a potential dietary compound for prevention of EBV reactivation.

Self-assembly of single-wall carbon nanotubes during the cooling process of hot carbon gas.

PubMed

Wen, Yushi; Zheng, Ke; Long, Xinping; Li, Ming; Xue, Xianggui; Dai, Xiaogan; Deng, Chuan

2018-04-25

In this work, self-assembly mechanism of single-wall carbon nanotube (SWCNT) during the annealing process of hot gaseous carbon is presented using reactive force field (ReaxFF)-based reactive molecular simulations. A series of simulations were performed on the evolution of reactive carbon gas. The simulation results show that the reactive carbon gas can be assembled into regular SWCNT without a catalyst. Five distinct stages of SWCNT self-assembly are proposed. For some initial configurations, the CNT was found to spin at an ultra-high rate after the nucleation. Graphical abstract Self-assembly process of single-wall carbon nanotube from the annealing of hot gaseous carbon.

Identification of the conserved hypothetical protein BPSL0317 in Burkholderia pseudomallei K96243

NASA Astrophysics Data System (ADS)

Yusoff, Nur Syamimi; Damiri, Nadzirah; Firdaus-Raih, Mohd

2014-09-01

Burkholderia pseudomallei K96243 is the causative agent of melioidosis, a disease which is endemic in Northern Australia and Southeastern Asia. The genome encodes several essential proteins including those currently annotated as hypothetical proteins. We studied the conservation and the essentiality of expressed hypothetical proteins in normal and different stress conditions. Based on the comparative genomics, we identified a hypothetical protein, BPSL0317, a potential essential gene that is being expressed in all normal and stress conditions. BPSL0317 is also phylogenetically conserved in the Burkholderiales order suggesting that this protein is crucial for survival among the order's members. BPSL0317 therefore has a potential to be a candidate antimicrobial drug target for this group of bacteria.

Space commercialization: Analysis of R and D investments with long time horizons

NASA Technical Reports Server (NTRS)

Sheahen, T. P.

1984-01-01

By following a single hypothetical example through a series of variations, the way different potential investors might look at the opportunity to participate in space commercialization is described. The example itself is fairly typical of commercial opportunities in space. The chief characteristics are a steadily increasing requirement for capital infusion over an 8 year period, followed by a very generous stream of profits running another decade or more beyond. There is a decision point at 3 years, at the conclusion of laboratory R&D; and another at 6 years, following 2 initial space flights.

Hydrogen-bond coordination in organic crystal structures: statistics, predictions and applications.

PubMed

Galek, Peter T A; Chisholm, James A; Pidcock, Elna; Wood, Peter A

2014-02-01

Statistical models to predict the number of hydrogen bonds that might be formed by any donor or acceptor atom in a crystal structure have been derived using organic structures in the Cambridge Structural Database. This hydrogen-bond coordination behaviour has been uniquely defined for more than 70 unique atom types, and has led to the development of a methodology to construct hypothetical hydrogen-bond arrangements. Comparing the constructed hydrogen-bond arrangements with known crystal structures shows promise in the assessment of structural stability, and some initial examples of industrially relevant polymorphs, co-crystals and hydrates are described.

Initial sediment transport model of the mining-affected Aries River Basin, Romania

USGS Publications Warehouse

Friedel, Michael J.; Linard, Joshua I.

2008-01-01

The Romanian government is interested in understanding the effects of existing and future mining activities on long-term dispersal, storage, and remobilization of sediment-associated metals. An initial Soil and Water Assessment Tool (SWAT) model was prepared using available data to evaluate hypothetical failure of the Valea Sesei tailings dam at the Rosia Poieni mine in the Aries River basin. Using the available data, the initial Aries River Basin SWAT model could not be manually calibrated to accurately reproduce monthly streamflow values observed at the Turda gage station. The poor simulation of the monthly streamflow is attributed to spatially limited soil and precipitation data, limited constraint information due to spatially and temporally limited streamflow measurements, and in ability to obtain optimal parameter values when using a manual calibration process. Suggestions to improve the Aries River basin sediment transport model include accounting for heterogeneity in model input, a two-tier nonlinear calibration strategy, and analysis of uncertainty in predictions.

[Organization and expression of poliovirus genome].

PubMed

Vevcherenko, S G

1984-01-01

In the present paper on the basis of analysis of literary data it is postulated that along with the AUG codon at N743 there exists a second initiation codon in the poliovirus RNA (the AUG codon at N586). The translation initiated at N586 can be transferred to the phase of the major reading frame by removing the small hairpin N732-N744 formed near the first initiation site, or by removing the small region N739-N745. In the first case at the boundary between the hypothetical leader peptide encoded by the 5'-terminus of the long, open reading frame of the spliced poliovirus RNA and the capsid protein VP4 must be the Gln-Gly proteolytic cleavage signal, and in the second case--the Tyr-Gly signal. In both cases the leader peptide can be chipped off by the virus specific proteinase. It is supposed that the exon-intronic structure of the poliovirus genome is needed for coordination of translation and transcription during the poliovirus reproduction cycle.

Gone for 60 seconds: reactivation length determines motor memory degradation during reconsolidation.

PubMed

de Beukelaar, Toon T; Woolley, Daniel G; Wenderoth, Nicole

2014-10-01

When a stable memory is reactivated it becomes transiently labile and requires restabilization, a process known as reconsolidation. Animal studies have convincingly demonstrated that during reconsolidation memories are modifiable and can be erased when reactivation is followed by an interfering intervention. Few studies have been conducted in humans, however, and results are inconsistent regarding the extent to which a memory can be degraded. We used a motor sequence learning paradigm to show that the length of reactivation constitutes a crucial boundary condition determining whether human motor memories can be degraded. In our first experiment, we found that a short reactivation (less than 60 sec) renders the memory labile and susceptible to degradation through interference, while a longer reactivation does not. In our second experiment, we reproduce these results and show a significant linear relationship between the length of memory reactivation and the detrimental effect of the interfering task performed afterwards, i.e., the longer the reactivation, the smaller the memory loss due to interference. Our data suggest that reactivation via motor execution activates a time-dependent process that initially destabilizes the memory, which is then followed by restabilization during further practice.

Savings estimate for a Medicare insured group

PubMed Central

Birnbaum, Howard; Holland, Stephen K.; Lenhart, Gregory; Reilly, Helena L.; Hoffman, Kevin; Pardo, Dennis P.

1991-01-01

Estimates of the savings potential of a managed-care program for a Medicare retiree population in Michigan under a hypothetical Medicare insured group (MIG) are presented in this article. In return for receiving an experience-rated capitation payment, a MIG would administer all Medicare and employer complementary benefits for its enrollees. A study of the financial and operational feasibility of implementing a MIG for retirees of a national corporation involving an analysis of 1986 claims data finds that selected managed-care initiatives implemented by a MIG would generate an annual savings of 3.8 percent of total (Medicare plus complementary) expenditures. Although savings are less than the 5 percent to be retained by Medicare, this finding illustrates the potential for savings from managed-care initiatives to Medicare generally and to MIGs elsewhere, where savings may be greater if constraints are less restrictive. PMID:10113700

Ginseng and Ginkgo Biloba Effects on Cognition as Modulated by Cardiovascular Reactivity: A Randomised Trial

PubMed Central

Ong Lai Teik, Derek; Lee, Xiao Shiang; Lim, Chu Jian; Low, Chia Mei; Muslima, Mariyam; Aquili, Luca

2016-01-01

Background There is some evidence to suggest that ginseng and Ginkgo biloba can improve cognitive performance, however, very little is known about the mechanisms associated with such improvement. Here, we tested whether cardiovascular reactivity to a task is associated with cognitive improvement. Methodology/Principal findings Using a double-blind, placebo controlled, crossover design, participants (N = 24) received two doses of Panax Ginseng (500, 1000 mg) or Ginkgo Biloba (120, 240 mg) (N = 24), and underwent a series of cognitive tests while systolic, diastolic, and heart rate readings were taken. Ginkgo Biloba improved aspects of executive functioning (Stroop and Berg tasks) in females but not in males. Ginseng had no effect on cognition. Ginkgo biloba in females reversed the initial (i.e. placebo) increase in cardiovascular reactivity (systolic and diastolic readings increased compared to baseline) to cognitive tasks. This effect (reversal) was most notable after those tasks (Stroop and Iowa) that elicited the greatest cardiovascular reactivity during placebo. In males, although ginkgo also decreased cardiovascular readings, it did so from an initial (placebo) blunted response (i.e. decrease or no change from baseline) to cognitive tasks. Ginseng, on the contrary, increased cardiovascular readings compared to placebo. Conclusions/Significance These results suggest that cardiovascular reactivity may be a mechanism by which ginkgo but not ginseng, in females is associated with certain forms of cognitive improvement. Trial Registration ClinicalTrials.gov NCT02386852 PMID:26938637

Reuse of waste beer yeast sludge for biosorptive decolorization of reactive blue 49 from aqueous solution.

PubMed

Wang, Baoe; Guo, Xiu

2011-06-01

Reactive blue 49 was removed from aqueous solution by biosorption using powder waste sludge composed of Saccharomyces cerevisiae from the beer-brewing industry. The effect of initial pH, temperature and the biosorption thermodynamics, equilibrium, kinetics was investigated in this study. It was found that the biosorption capacity was at maximum at initial pH 3, that the effect of temperature on biosorption of reactive blue 49 was only slight in relation to the large biosorption capacity (25°C, 361 mg g(-1)) according as the biosorption capacity decreased only 43 mg g(-1) at the temperature increased from 25 to 50°C. The biosorption was spontaneous, exothermic in nature and the dye molecules movements decreased slightly in random at the solid/liquid interface during the biosorption of dye on biosorbents. The biosorption equilibrium data could be described by Freundich isotherm model. The biosorption rates were found to be consistent with a pseudo-second-order kinetics model. The functional group interaction analysis between waste beer yeast sludge and reactive blue 49 by the aid of Fourier transform infrared (abbr. FTIR) spectroscopy indicated that amino components involved in protein participated in the biosorption process, which may be achieved by the mutual electrostatic adsorption process between the positively charged amino groups in waste beer yeast sludge with negatively charged sulfonic groups in reactive blue 49.

Ginseng and Ginkgo Biloba Effects on Cognition as Modulated by Cardiovascular Reactivity: A Randomised Trial.

PubMed

Ong Lai Teik, Derek; Lee, Xiao Shiang; Lim, Chu Jian; Low, Chia Mei; Muslima, Mariyam; Aquili, Luca

2016-01-01

There is some evidence to suggest that ginseng and Ginkgo biloba can improve cognitive performance, however, very little is known about the mechanisms associated with such improvement. Here, we tested whether cardiovascular reactivity to a task is associated with cognitive improvement. Using a double-blind, placebo controlled, crossover design, participants (N = 24) received two doses of Panax Ginseng (500, 1000 mg) or Ginkgo Biloba (120, 240 mg) (N = 24), and underwent a series of cognitive tests while systolic, diastolic, and heart rate readings were taken. Ginkgo Biloba improved aspects of executive functioning (Stroop and Berg tasks) in females but not in males. Ginseng had no effect on cognition. Ginkgo biloba in females reversed the initial (i.e. placebo) increase in cardiovascular reactivity (systolic and diastolic readings increased compared to baseline) to cognitive tasks. This effect (reversal) was most notable after those tasks (Stroop and Iowa) that elicited the greatest cardiovascular reactivity during placebo. In males, although ginkgo also decreased cardiovascular readings, it did so from an initial (placebo) blunted response (i.e. decrease or no change from baseline) to cognitive tasks. Ginseng, on the contrary, increased cardiovascular readings compared to placebo. These results suggest that cardiovascular reactivity may be a mechanism by which ginkgo but not ginseng, in females is associated with certain forms of cognitive improvement. ClinicalTrials.gov NCT02386852.

Towards Development of a Super Ceramic Composite - Initial Investigation into Improvement of Strength and Toughness of Polycrystalline Ceramics

DTIC Science & Technology

2012-08-01

sintering of SiC. James Lill (2010) evaluated the Reactive Empirical Bond Order potentials of Brenner (Brenner 1990); the Adaptive Intermolecular Reactive...Protection mechanisms of the iron-plated armor of a deep-sea hydrothermal vent gastropod . PNAS 107(3):987-997. Yu, J., S. B. Sinnott, and S. R. Phillpot

Significant levels of extracellular reactive oxygen species produced by brown rot basidiomycetes on cellulose

Treesearch

Roni Cohen; Kenneth A. Jensen; Carl J. Houtman; Kenneth E. Hammel

2002-01-01

It is often proposed that brown rot basidiomycetes use extracellular reactive oxygen species (ROS) to accomplish the initial depolymerization of cellulose in wood, but little evidence has been presented to show that the fungi produce these oxidants in physiologically relevant quantities. We used [14C]phenethyl polyacrylate as a radical trap to estimate extracellular...

THE APPLICATION OF IN SITU PERMEABLE REACTIVE (ZERO-VALENT IRON) BARRIER TECHNOLOGY FOR THE REMEDIATION OF CHROMATE-CONTAMINATED GROUNDWATER: A FIELD TEST

EPA Science Inventory

A small-scale field test was initiated in September 1994 to evaluate the in situ remediation of groundwater contaminated with chromate using a permeable reactive barrier composed of a mixture of zero-valent Fe, sand and aquifer sediment. The site used was an old chrome-plating f...

A distributed agent architecture for real-time knowledge-based systems: Real-time expert systems project, phase 1

NASA Technical Reports Server (NTRS)

Lee, S. Daniel

1990-01-01

We propose a distributed agent architecture (DAA) that can support a variety of paradigms based on both traditional real-time computing and artificial intelligence. DAA consists of distributed agents that are classified into two categories: reactive and cognitive. Reactive agents can be implemented directly in Ada to meet hard real-time requirements and be deployed on on-board embedded processors. A traditional real-time computing methodology under consideration is the rate monotonic theory that can guarantee schedulability based on analytical methods. AI techniques under consideration for reactive agents are approximate or anytime reasoning that can be implemented using Bayesian belief networks as in Guardian. Cognitive agents are traditional expert systems that can be implemented in ART-Ada to meet soft real-time requirements. During the initial design of cognitive agents, it is critical to consider the migration path that would allow initial deployment on ground-based workstations with eventual deployment on on-board processors. ART-Ada technology enables this migration while Lisp-based technologies make it difficult if not impossible. In addition to reactive and cognitive agents, a meta-level agent would be needed to coordinate multiple agents and to provide meta-level control.

Effect of cefodizime and ceftriaxone on phagocytic function in patients with severe infections.

PubMed Central

Wenisch, C; Parschalk, B; Hasenhündl, M; Wiesinger, E; Graninger, W

1995-01-01

Thirty patients with severe bacterial infections were treated with 50 mg of cefodizime per kg of body weight once daily or 50 mg of ceftriaxone per kg once daily for 10 +/- 3 days. The effect of cefodizime and ceftriaxone on the phagocytic capacity and generation of reactive oxygen intermediates after phagocytosis by granulocytes was assessed prior to, during, and after therapy. Flow cytometry was used to study phagocytic capacity by measuring the uptake of fluorescein-labeled bacteria. The generation of reactive oxygen intermediates after phagocytosis was estimated by the quantification of the intracellular conversion of dihydrorhodamine 123 to rhodamine 123. Prior to therapy, patients in both groups exhibited a decreased capacity to phagocytize Escherichia coli and subsequently to generate reactive oxygen intermediates. Granulocyte function increased after the initiation of therapy and normalized within 7 days for the ceftriaxone-treated patients and within 3 days for the cefodizime group (P < 0.05). In the cefodizime group, an enhancement of phagocytic capacity was observed 14 days after the initiation of therapy (P < 0.05). Prior to therapy, phagocytic capacity was significantly correlated with the generation of reactive oxygen products (r = 0.674 and P < 0.005). PMID:7793871

Modeling the ignition of a copper oxide aluminum thermite

NASA Astrophysics Data System (ADS)

Lee, Kibaek; Stewart, D. Scott; Clemenson, Michael; Glumac, Nick; Murzyn, Christopher

2017-01-01

An experimental "striker confinement" shock compression experiment was developed in the Glumac-group at the University of Illinois to study ignition and reaction in composite reactive materials. These include thermitic and intermetallic reactive powders. Sample of materials such as a thermite mixture of copper oxide and aluminum powders are initially compressed to about 80 percent full density. Two RP-80 detonators simultaneously push steel bars into the reactive material and the resulting compression causes shock compaction of the material and rapid heating. At that point one observes significant reaction and propagation of fronts. But the fronts are peculiar in that they are comprised of reactive events that can be traced to the reaction of the initially separated reactants of copper oxide and aluminum that react at their mutual interfaces, that nominally make copper liquid and aluminum oxide products. We discuss our model of the ignition of the copper oxide aluminum thermite in the context of the striker experiment and how a Gibbs formulation model [1], that includes multi-components for liquid and solid phases of aluminum, copper oxide, copper and aluminum oxide, can predict the events observed at the particle scale in the experiments.

Computational Identification and Analysis of the Key Biosorbent Characteristics for the Biosorption Process of Reactive Black 5 onto Fungal Biomass

PubMed Central

Yang, Yu-Yi; Li, Ze-Li; Wang, Guan; Zhao, Xiao-Ping; Crowley, David E.; Zhao, Yu-Hua

2012-01-01

The performances of nine biosorbents derived from dead fungal biomass were investigated for their ability to remove Reactive Black 5 from aqueous solution. The biosorption data for removal of Reactive Black 5 were readily modeled using the Langmuir adsorption isotherm. Kinetic analysis based on both pseudo-second-order and Weber-Morris models indicated intraparticle diffusion was the rate limiting step for biosorption of Reactive Black 5 on to the biosorbents. Sorption capacities of the biosorbents were not correlated with the initial biosorption rates. Sensitivity analysis of the factors affecting biosorption examined by an artificial neural network model showed that pH was the most important parameter, explaining 22%, followed by nitrogen content of biosorbents (16%), initial dye concentration (15%) and carbon content of biosorbents (10%). The biosorption capacities were not proportional to surface areas of the sorbents, but were instead influenced by their chemical element composition. The main functional groups contributing to dye sorption were amine, carboxylic, and alcohol moieties. The data further suggest that differences in carbon and nitrogen contents of biosorbents may be used as a selection index for identifying effective biosorbents from dead fungal biomass. PMID:22442697

Hemorrhagic Cystitis due to BK Reactivation in a Young Female Treated for Hodgkin-Disease

PubMed Central

Le Calloch, R.; Ianotto, J. C.; Berthou, C.; Tempescul, A.

2011-01-01

Hodgkin's lymphoma is a disease with a high rate of curability under classic chemo-radiotherapy regimes. Complications due to chemotherapy could include viral reactivation due to chronic lymphopenia. BK virus (BKV) is a polyoma virus belonging to the Papovaviridae family with antibody seroprevalences in healthy populations varying from 60% to 80%. Initial infections are asymptomatic usually occur in early childhood, after which the viruses remain latent in the kidneys or urothelium. Reactivation of BKV occurs in individuals with severe immunosuppression during HIV infections, transplantation or, exceptionally, after classical chemotherapy. BKV incidence is approximately 0% to 5% in immunocompetent individuals. Reactivation is associated with nephropathy and haemorrhagic cystitis. Herein, we present a case of a haemorrhagic cystitis due to BKV reactivation in a patient with Hodgkin's disease treated with chemotherapy. PMID:22937308

G T-Mohr Start-up Reactivity Insertion Transient Analysis Using Simulink

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

Fard, Mehdi Reisi; Blue, Thomas E.; Miller, Don W.

2006-07-01

As a part of a Department of Energy-Nuclear Engineering Research Initiative (NERI) Project, we at OSU are investigating SiC semiconductor detectors as neutron power monitors for Generation IV power reactors. As a part of this project, we are investigating the power monitoring requirements for a specific type of Generation IV reactor, namely the GT-MHR. To evaluate the power monitoring requirements for the GT-MHR that are most demanding for a SiC diode power monitor, we have developed a Simulink model to study the transient behavior of the GT-MHR. In this paper, we describe the application of the Simulink code to themore » analysis of a series of Start-up Reactivity Insertion Transients (SURITs). The SURIT is considered to be a limiting protectable accident in terms of establishing the dynamic range of a SiC power monitor because of the low count rate of the detector during the start-up and absence of the reactivity feedback mechanism at the beginning of transient. The SURIT is studied with the ultimate goal of identifying combinations of 1) reactor power scram setpoints and 2) cram initiation times (the time in which a scram must be initiated once the setpoint is exceeded) for which the GT-MHR core is protected in the event of a continuous withdrawal of a control rod bank from the core from low powers. The SURIT is initiated by withdrawing a rod bank when the reactor is cold (300 K) and sub-critical at the BOEC (Beginning of Equilibrium Cycle) condition. Various initial power levels have been considered corresponding to various degrees of sub-criticality and various source strengths. An envelope of response is determined to establish which initial powers correspond to the worst case SURIT. (authors)« less

Hot spot formation and chemical reaction initiation in shocked HMX crystals with nanovoids: a large-scale reactive molecular dynamics study.

PubMed

Zhou, Tingting; Lou, Jianfeng; Zhang, Yangeng; Song, Huajie; Huang, Fenglei

2016-07-14

We report million-atom reactive molecular dynamic simulations of shock initiation of β-cyclotetramethylene tetranitramine (β-HMX) single crystals containing nanometer-scale spherical voids. Shock induced void collapse and subsequent hot spot formation as well as chemical reaction initiation are observed which depend on the void size and impact strength. For an impact velocity of 1 km s(-1) and a void radius of 4 nm, the void collapse process includes three stages; the dominant mechanism is the convergence of upstream molecules toward the centerline and the downstream surface of the void forming flowing molecules. Hot spot formation also undergoes three stages, and the principal mechanism is kinetic energy transforming to thermal energy due to the collision of flowing molecules on the downstream surface. The high temperature of the hot spot initiates a local chemical reaction, and the breakage of the N-NO2 bond plays the key role in the initial reaction mechanism. The impact strength and void size have noticeable effects on the shock dynamical process, resulting in a variation of the predominant mechanisms leading to void collapse and hot spot formation. Larger voids or stronger shocks result in more intense hot spots and, thus, more violent chemical reactions, promoting more reaction channels and generating more reaction products in a shorter duration. The reaction products are mainly concentrated in the developed hot spot, indicating that the chemical reactivity of the hmx crystal is greatly enhanced by void collapse. The detailed information derived from this study can aid a thorough understanding of the role of void collapse in hot spot formation and the chemical reaction initiation of explosives.

Cost-benefit analysis of vaccination against Mycobacterium avium ssp. paratuberculosis in dairy cattle, given its cross-reactivity with tuberculosis tests.

PubMed

Groenendaal, Huybert; Zagmutt, Francisco J; Patton, Elisabeth A; Wells, Scott J

2015-09-01

Johne's disease (JD), or paratuberculosis, is a chronic enteric disease of ruminants, caused by infection with Mycobacterium avium ssp. paratuberculosis (MAP). Johne's disease causes considerable economic losses to the US dairy industry, estimated to be over $200 million annually. Available control strategies include management measures to improve calf hygiene, test-and-cull strategies, and vaccination. Although the first 2 strategies have shown to reduce the prevalence of MAP, they require dedicated and long-term efforts from dairy producers, with often relatively slow progress. As a result, uptake of both strategies has not been as wide as expected given the economic benefits especially of improved hygiene. Vaccination has also been found to reduce the prevalence and economic losses of JD, but most economic estimates have been based on simulation of hypothetical vaccines. In addition, if an animal is vaccinated, cross-reactivity between MAP antibodies and bovine tuberculosis (BTB) antigens may occur, decreasing the specificity of BTB tests. Therefore, MAP vaccination would cause additional indirect costs to the BTB surveillance and control program. The objective of the present study was to use data from a MAP vaccine trial together with an epidemiologic and economic model to estimate the direct on-farm benefits of MAP vaccination and to estimate the indirect costs of MAP vaccination due to the cross-reactivity with BTB tests. Direct economic benefits of MAP vaccination were estimated at $8.03 (90% predictive interval: -$25.97 to $41.36) per adult animal per year, all accruing to the dairy producers. This estimate is likely an underestimation of the true direct benefits of MAP vaccination. In addition, indirect economic costs due to cross-reactivity were $2.14 per adult animal per year, making MAP vaccination economically attractive. Only in regions or states with a high frequency of BTB testing (because of, for example, Mycobacterium bovis outbreaks in a wild deer population) and areas where typically small groups of animals are BTB tested would MAP vaccination not be economically attractive. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Early Stage of Oxidation on Titanium Surface by Reactive Molecular Dynamics Simulation

DOE PAGES

Yang, Liang; Wang, C. Z.; Lin, Shiwei; ...

2018-01-01

Understanding of metal oxidation is very critical to corrosion control, catalysis synthesis, and advanced materials engineering. Metal oxidation is a very complex phenomenon, with many different processes which are coupled and involved from the onset of reaction. In this work, the initial stage of oxidation on titanium surface was investigated in atomic scale by molecular dynamics (MD) simulations using a reactive force field (ReaxFF). We show that oxygen transport is the dominant process during the initial oxidation. Our simulation also demonstrate that a compressive stress was generated in the oxide layer which blocked the oxygen transport perpendicular to the Titaniummore » (0001) surface and further prevented oxidation in the deeper layers. As a result, the mechanism of initial oxidation observed in this work can be also applicable to other self-limiting oxidation.« less

International Considerations Associated with Economic Planning for Recovery from a Generalized Disaster

DTIC Science & Technology

1988-06-01

typical approach in addressing the recovery problem has been to impose a hypothetical nuclear disaster scenario on the U.S. economy and to speculate on...system and international trade in the aftermath of a nuclear disaster in Chapter 7 is provided in the context of a number of dimensions of a...hypothetical nuclear conflict. The dimensions of a hypothetical nuclear disaster must be defined because planning must necessarily be flexible enough to

Postocclusive reactive hyperemia in hand-arm vibration syndrome.

PubMed

Stoyneva, Zlatka

2016-01-01

To assess laser Doppler-recorded postocclusive reactive hyperemic responses in vibration-induced Raynaud's phenomenon and compare it with primary and secondary to sclerodermy Raynaud's phenomenon. Thirty patients with vibration-induced Raynaud's phenomenon and 30 healthy controls and patients with primary and secondary to sclerodermy Raynaud's phenomenon were investigated. Fingerpulp skin blood flow was monitored by laser Doppler flowmetry during postocclusive reactive hyperemia test. Lower initial perfusion values were established in all the patients with Raynaud's phenomenon compared to the healthy controls (p < 0.0001). The postocclusive reactive hyperemic peak was lower in all the Raynaud's phenomenon groups compared to the controls (p < 0.0001). The postocclusive and basal perfusions were lower in the secondary Raynaud's phenomenon groups compared to the control and the primary Raynaud's phenomenon groups (p < 0.0001). The velocities to postocclusive hyperemic peak were lower in all the Raynaud's phenomenon patients (p < 0.0001), so were in the vibration-induced (p < 0.002) and the sclerodermy Raynaud's phenomenon (p < 0.004) groups in relation to the primary Raynaud's phenomenon group. The perfusion values and the velocities were significantly influenced by the initial superficial skin temperatures and perfusions, while the velocities were dependent also on gender, and the hyperemic peak on age. Postocclusive reactive hyperemia is abnormal in all Raynaud's phenomenon patients. Laser Doppler-recorded reactive hyperemia test contributes to diagnosing Raynaud's phenomenon and has proved to be valuable for group analysis. The applied method is not sensitive enough to discriminate adequately the type of Raynaud's phenomenon among individual cases. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Altruism costs—the cheap signal from amygdala

PubMed Central

Sundberg, Marcus; Maeder, Johanna; Fransson, Peter; Petrovic, Predrag; Isacsson, Gunnar; Karlström, Anders; Ingvar, Martin

2014-01-01

When people state their willingness to pay for something, the amount usually differs from the behavior in a real purchase situation. The discrepancy between a hypothetical answer and the real act is called hypothetical bias. We investigated neural processes of hypothetical bias regarding monetary donations to public goods using fMRI with the hypothesis that amygdala codes for real costs. Real decisions activated amygdala more than hypothetical decisions. This was observed for both accepted and rejected proposals. The more the subjects accepted real donation proposals the greater was the activity in rostral anterior cingulate cortex—a region known to control amygdala but also neural processing of the cost-benefit difference. The presentation of a charitable donation goal evoked an insula activity that predicted the later decision to donate. In conclusion, we have identified the neural mechanisms underlying real donation behavior, compatible with theories on hypothetical bias. Our findings imply that the emotional system has an important role in real decision making as it signals what kind of immediate cost and reward an outcome is associated with. PMID:23945997

Cu/Mn bimetallic catalysis enables carbonylative Suzuki–Miyaura coupling with unactivated alkyl electrophiles† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc01170a Click here for additional data file.

PubMed Central

Pye, Dominic R.; Cheng, Li-Jie

2017-01-01

A bimetallic system consisting of Cu-carbene and Mn-carbonyl co-catalysts was employed for carbonylative C–C coupling of arylboronic esters with alkyl halides, allowing for the convergent synthesis of ketones. The system operates under mild conditions and exhibits complementary reactivity to Pd catalysis. The method is compatible with a wide range of arylboronic ester nucleophiles and proceeds smoothly for both primary and secondary alkyl iodide electrophiles. Preliminary mechanistic experiments corroborate a hypothetical catalytic mechanism consisting of co-dependent cycles wherein the Cu-carbene co-catalyst engages in transmetallation to generate an organocopper nucleophile, while the Mn-carbonyl co-catalyst activates the alkyl halide electrophile by single-electron transfer and then undergoes reversible carbonylation to generate an acylmanganese electrophile. The two cycles then intersect with a heterobimetallic, product-releasing C–C coupling step. PMID:28966784

Mitochondrion-Permeable Antioxidants to Treat ROS-Burst-Mediated Acute Diseases

PubMed Central

Zhang, Zhong-Wei; Xu, Xiao-Chao; Liu, Ting

2016-01-01

Reactive oxygen species (ROS) play a crucial role in the inflammatory response and cytokine outbreak, such as during virus infections, diabetes, cancer, cardiovascular diseases, and neurodegenerative diseases. Therefore, antioxidant is an important medicine to ROS-related diseases. For example, ascorbic acid (vitamin C, VC) was suggested as the candidate antioxidant to treat multiple diseases. However, long-term use of high-dose VC causes many side effects. In this review, we compare and analyze all kinds of mitochondrion-permeable antioxidants, including edaravone, idebenone, α-Lipoic acid, carotenoids, vitamin E, and coenzyme Q10, and mitochondria-targeted antioxidants MitoQ and SkQ and propose astaxanthin (a special carotenoid) to be the best antioxidant for ROS-burst-mediated acute diseases, like avian influenza infection and ischemia-reperfusion. Nevertheless, astaxanthins are so unstable that most of them are inactivated after oral administration. Therefore, astaxanthin injection is suggested hypothetically. The drawbacks of the antioxidants are also reviewed, which limit the use of antioxidants as coadjuvants in the treatment of ROS-associated disorders. PMID:26649144

ATWS at Browns Ferry Unit One - accident sequence analysis

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

Harrington, R.M.; Hodge, S.A.

1984-07-01

This study describes the predicted response of Unit One at the Browns Ferry Nuclear Plant to a postulated complete failure to scram following a transient occurrence that has caused closure of all Main Steam Isolation Valves (MSIVs). This hypothetical event constitutes the most severe example of the type of accident classified as Anticipated Transient Without Scram (ATWS). Without the automatic control rod insertion provided by scram, the void coefficient of reactivity and the mechanisms by which voids are formed in the moderator/coolant play a dominant role in the progression of the accident. Actions taken by the operator greatly influence themore » quantity of voids in the coolant and the effect is analyzed in this report. The progression of the accident sequence under existing and under recommended procedures is discussed. For the extremely unlikely cases in which equipment failure and wrongful operator actions might lead to severe core damage, the sequence of emergency action levels and the associated timing of events are presented.« less

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

Zheng, L.; Spycher, N.; Xu, T.

In this study, reactive transport simulations were used to assess the mobilization and transport of organics with supercritical CO{sub 2} (SCC), and the co-injection and transport of H{sub 2}S with SCC. These processes were evaluated at conditions of typical storage reservoirs, and for cases of hypothetical leakage from a reservoir to an overlying shallower fresh water aquifer. Modeling capabilities were developed to allow the simulation of multiphase flow and transport of H{sub 2}O, CO{sub 2}, H{sub 2}S, as well as specific organic compounds (benzene), coupled with multicomponent geochemical reaction and transport. This included the development of a new simulator, TMVOC-REACT,more » starting from existing modules of the TOUGH2 family of codes. This work also included an extensive literature review, calculation, and testing of phase-partitioning properties for mixtures of the phases considered. The reactive transport simulations presented in this report are primarily intended to illustrate the capabilities of the new simulator. They are also intended to help evaluate and understand various processes at play, in a more qualitative than quantitative manner, and only for hypothetical scenarios. Therefore, model results are not intended as realistic assessments of groundwater quality changes for specific locations, and they certainly do not provide an exhaustive evaluation of all possible site conditions, especially given the large variability and uncertainty in hydrogeologic and geochemical parameter input into simulations. The first step in evaluating the potential mobilization and transport of organics was the identification of compounds likely to be present in deep storage formations, and likely to negatively impact freshwater aquifers if mobilized by SCC. On the basis of a literature review related to the occurrence of these organic compounds, their solubility in water and SCC, and their toxicity (as reflected by their maximum contaminant levels MCL), benzene was selected as a key compound for inclusion into numerical simulations. Note that considering additional organic compounds and/or mixtures of such compounds in the simulations was beyond the scope of this study, because of the effort required to research, calculate, and validate the phase-partitioning data necessary for simulations. The injection of CO{sub 2} into a deep saline aquifer was simulated, followed by modeling the leaching of benzene by SCC and transport of benzene to an overlying aquifer along a hypothetical leakage pathway. One- and two-dimensional models were set up for this purpose. The target storage formation was assumed to initially contain about 10{sup -4} ppm benzene. Model results indicate that: (1) SCC efficiently extracts benzene from the storage formation. (2) Assuming equilibrium, the content of benzene in SCC is roportional to the concentration of benzene in the aqueous and solid phases. (3) Benzene may co-migrate with CO{sub 2} into overlying aquifers if a leakage pathway is present. Because the aqueous solubility of benzene in contact with CO{sub 2} is lower than the aqueous solubility of CO{sub 2}, benzene is actually enriched in the CO{sub 2} phase as the plume advances. (4) For the case studied here, the resulting aqueous benzene concentration in the overlying aquifer is on the same order of magnitude as the initial concentration in the storage formation. This generic modeling study illustrates, in a semi-quantitative manner, the possible mobilization of benzene by SCC. The extent to which the mobilization of this organic compound evolves temporally and spatially depends on a large number of controlling parameters and is largely site specific. Therefore, for more 'truly' predictive work, further sensitivity studies should be conducted, and further modeling should be integrated with site-specific laboratory and/or field experimental data. The co-injection of H{sub 2}S with CO{sub 2} into a deep saline aquifer was also simulated. In addition, the model considered leakage of the supercritical CO{sub 2}+H{sub 2}S mixture along a preferential pathway to an overlying fresh-water aquifer, followed by reaction of the CO{sub 2}+H{sub 2}S mixture with that aquifer. A simple 2-D model that included a storage formation and a sealing aquitard was developed to simulate the movement of H{sub 2}S in a typical CO{sub 2} storage formation. Model results indicate that H{sub 2}S is stripped off at the edge of the advancing supercritical plume, because of the H{sub 2}S preferential solubility in water compared to CO{sub 2}. The magnitude of H{sub 2}S preferential dissolution, however, decreases with decreasing temperature and pressure. To capture this behavior and evaluate the breakthrough of H{sub 2}S through a leakage pathway (from the deep storage formation to a shallower aquifer), another model was constructed, considering a storage formation, an overlying aquifer, and a vertical leakage pathway between them.« less

Memory Reactivation Predicts Resistance to Retroactive Interference: Evidence from Multivariate Classification and Pattern Similarity Analyses

PubMed Central

Rugg, Michael D.

2016-01-01

Memory reactivation—the reinstatement of processes and representations engaged when an event is initially experienced—is believed to play an important role in strengthening and updating episodic memory. The present study examines how memory reactivation during a potentially interfering event influences memory for a previously experienced event. Participants underwent fMRI during the encoding phase of an AB/AC interference task in which some words were presented twice in association with two different encoding tasks (AB and AC trials) and other words were presented once (DE trials). The later memory test required retrieval of the encoding tasks associated with each of the study words. Retroactive interference was evident for the AB encoding task and was particularly strong when the AC encoding task was remembered rather than forgotten. We used multivariate classification and pattern similarity analysis (PSA) to measure reactivation of the AB encoding task during AC trials. The results demonstrated that reactivation of generic task information measured with multivariate classification predicted subsequent memory for the AB encoding task regardless of whether interference was strong and weak (trials for which the AC encoding task was remembered or forgotten, respectively). In contrast, reactivation of neural patterns idiosyncratic to a given AB trial measured with PSA only predicted memory when the strength of interference was low. These results suggest that reactivation of features of an initial experience shared across numerous events in the same category, but not features idiosyncratic to a particular event, are important in resisting retroactive interference caused by new learning. SIGNIFICANCE STATEMENT Reactivating a previously encoded memory is believed to provide an opportunity to strengthen the memory, but also to return the memory to a labile state, making it susceptible to interference. However, there is debate as to how memory reactivation elicited by a potentially interfering event influences subsequent retrieval of the memory. The findings of the current study indicate that reactivating features idiosyncratic to a particular experience during interference only influences subsequent memory when interference is relatively weak. Critically, reactivation of generic contextual information predicts subsequent source memory when retroactive interference is either strong and weak. The results indicate that reactivation of generic information about a prior episode mitigates forgetting due to retroactive interference. PMID:27076433

Improved Reactive Flow Modeling of the LX-17 Double Shock Experiments

NASA Astrophysics Data System (ADS)

Rehagen, Thomas J.; Vitello, Peter

2017-06-01

Over driven double shock experiments provide a measurement of the properties of the reaction product states of the insensitive high explosive LX-17 (92.5% TATB and 7.5% Kel-F by weight). These experiments used two flyer materials mounted on the end of a projectile to send an initial shock through the LX-17, followed by a second shock of a higher magnitude into the detonation products. In the experiments, the explosive was initially driven by the flyer plate to pressures above the Chapman-Jouguet state. The particle velocity history was recorded by Photonic Doppler Velocimetry (PDV) probes pointing at an aluminum foil coated LiF window. The PDV data shows a sharp initial shock and decay, followed by a rounded second shock. Here, the experimental results are compared to 2D and 3D Cheetah reactive flow modeling. Our default Cheetah reactive flow model fails to accurately reproduce the decay of the first shock or the curvature or strength of the second shock. A new model is proposed in which the carbon condensate produced in the reaction zone is controlled by a kinetic rate. This allows the carbon condensate to be initially out of chemical equilibrium with the product gas. This new model reproduces the initial detonation peak and decay, and matches the curvature of the second shock, however, it still over-predicts the strength of the second shock. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344.

Reactivation of pre-existing mechanical anisotropies during polyphase tectonic evolution: slip tendency analysis as a tool to constrain mechanical properties of rocks

NASA Astrophysics Data System (ADS)

Traforti, Anna; Bistacchi, Andrea; Massironi, Matteo; Zampieri, Dario; Di Toro, Giulio

2017-04-01

Intracontinental deformation within the upper crust is accommodated by nucleation of new faults (generally satisfying the Anderson's theory of faulting) or brittle reactivation of pre-existing anisotropies when certain conditions are met. How prone to reactivation an existing mechanical anisotropy or discontinuity is, depends on its mechanical strength compared to that of the intact rock and on its orientation with respect to the regional stress field. In this study, we consider how different rock types (i.e. anisotropic vs. isotropic) are deformed during a well-constrained brittle polyphase tectonic evolution to derive the mechanical strength of pre-existing anisotropies and discontinuities (i.e. metamorphic foliations and inherited faults/fractures). The analysis has been carried out in the Eastern Sierras Pampeanas of Central Argentina. These are a series of basement ranges of the Andean foreland, which show compelling evidence of a long-lasting brittle deformation history from the Early Carboniferous to Present time, with three main deformational events (Early Triassic to Early Jurassic NE-SW extension, Early Cretaceous NW-SE extension and Miocene to Present ENE-WNW compression). The study area includes both isotropic granitic bodies and anisotropic phyllosilicate-bearing rocks (gneisses and phyllites). In this environment, each deformation phase causes significant reactivation of the inherited structures and rheological anisotropies, or alternatively formation of neo-formed Andersonian faults, thus providing a multidirectional probing of mechanical properties of these rocks. A meso- and micro-structural analysis of brittle reactivation of metamorphic foliation or inherited faults/fractures revealed that different rock types present remarkable differences in the style of deformation (i.e., phyllite foliation is reactivated during the last compressional phase and cut by newly-formed Andersonian faults/fractures during the first two extensional regimes; instead, gneiss foliation is pervasively reactivated during all the tectonic phases). Considering these observations, we applied a Slip Tendency analysis to estimate the upper and lower bounds to the friction coefficient for slip along the foliations (μs) and along pre-existing faults/fractures (μf). If an hypothetical condition with simultaneous failure on the inherited mechanical discontinuity (foliation or pre-existing fault/fracture) and new Andersonian faults is assumed, the ratio between μsor μf and μ0(the average friction coefficient for intact isotropic rocks) can be calculated as μs (or μf) = NTs ṡ μ0(where NTs represents the normalized slip tendency of the analyzed discontinuity). When just reactivation of foliation/faults/fractures is observed (i.e. no newly-formed Andersonian faults are recognised), an upper bound to μsand μfcan be estimated as μs (or μf) < NTs ṡ μ0. By contrast, the lower bound to μsand μfcan be obtained as μs (or μf) > NTs ṡ μ0, when the mechanical anisotropies are not reactivated and new Andersonian faults nucleate. Applying the above analysis to multiple deformation phases and rock types, we were able to approximatively estimate μs < 0.4 (gneisses) and 0.1 < μs < 0.2 (phyllites) and μf ≈ 0.4 (phyllites) and 0.3 (gneisses).

Reactive histiocytosis of the orbit and posterior segment in a dog.

PubMed

Pumphrey, Stephanie A; Pizzirani, Stefano; Pirie, Christopher G; Sato, Amy F; Buckley, Faith I

2013-05-01

We present a case of reactive histiocytic disease involving the orbit, optic nerve, retina, and choroid in a Border Collie dog initially presenting for vision loss. Long-term partial return of vision has been achieved with systemic immunosuppression. Anterior segment and ocular surface manifestations of reactive histiocytic disease in dogs are relatively common. Posterior segment and orbital involvement, however, are minimally documented in the existing literature. To the authors' knowledge, this is the first report of disease confined to the orbit and posterior segment as well as the first report of vision loss as a presenting complaint for reactive histiocytic disease. Clinical, magnetic resonance imaging, cytologic, and histopathologic findings are reviewed. © 2012 American College of Veterinary Ophthalmologists.

Degradation of Glaukonite Sandstone as a Result of Alkali-Silica Reactions in Cement Mortar.

PubMed

Czapik, Przemysław

2018-05-30

The mechanism of concrete degradation as a result of an alkali-silica reaction (ASR) largely depends on the mineral composition and microstructure of the reactive aggregate. This paper shows the reactivity results of quartz-glaukonitic sandstone, which is mainly responsible for the reactivity of some post-glacial gravels, available in Poland. After initial petrographic observations under a light microscope, the mode of sandstone degradation triggered by the reaction with sodium and potassium hydroxides was identified using scanning electron microscopy (SEM). It has been found that chalcedony agglomerates present in sandstone are separated from the rock matrix and subsequently cause the cracks formation in this matrix. Additionally, microcrystalline and potentially reactive silica is also dispersed in sandstone cement.

Reliability of techniques used in the diagnosis of canine visceral leishmaniasis by the national control program in Brazil: A survey in an area of recent transmission.

PubMed

Belo, Vinícius Silva; Gregório, Eliana Aparecida; Teixeira-Neto, Rafael Gonçalves; da Rocha Lima, Ana Cristina Vianna Mariano; Pereira, Agnes Antônia Sampaio; Marcelino, Andreza Pain; Paz, Gustavo Fontes; da Silva, Eduardo Sérgio

2017-10-01

One of the key components of the Brazilian Program for the Control of Visceral Leishmaniasis (PCLV) is the euthanasia of Leishmania-infected canine reservoirs, the detection of which depends on a screening procedure involving a Dual Path Platform ® (DPP) immunoassay and a confirmatory enzyme-linked immunosorbent assay (ELISA). The aims of the present study were to evaluate the reliability of these techniques in a region of recent transmission of canine VL, to follow up the seroconversion 3-4 months after the initial diagnosis of DPP reactive but ELISA indeterminate or non-reactive dogs, and to identify the species of Leishmania in circulation in the area. Each animal was submitted to DPP under field conditions, performed by municipal health workers using peripheral blood (DPP-field), to DPP under laboratory conditions using serum (DPP-lab) and to ELISA using serum. The agreements between the tests were determined using McNemar's χ 2 test, Cohen's kappa coefficient (k) at the 95% confidence interval and prevalence-adjusted bias-adjusted kappa (PABAK). Of the 1130 dogs examined, 74.2% were non-reactive in all three tests applied. Based on the PCLV positive-infection criterion, seroprevalence was 8.9% (101/1130) with 83.2% (84/101) of infected animals showing reactivity in all three tests while 7.8% (8/101) were reactive in DPP-field and ELISA and 8.9% (9/101) in DPP-lab and ELISA. The proportions of disagreements were substantial in all comparisons. Inter-rater reliability between DPP-field and ELISA (k=0.55; PABAK=0.78) and DPP-lab and ELISA (k=0.59; PABAK=0.81) were considered moderate, while that between DPP-field and DPP-lab (k=0.61; PABAK=0.79) was classified as marginally good. The proportion of seroconversions in DPP reactive animals that were initially ELISA indeterminate was significantly higher than in those that were DPP reactive but initially ELISA non-reactive. Restriction fragment length polymorphism analysis revealed the presence of Leishmania infantum, the etiologic agent of VL, in bone marrow samples from VL-infected animals. Our data showed that the techniques and protocols currently employed in the PCLV screening approach are not entirely reliable. Further consideration should be given to monitoring dogs with undetermined results in ELISA and a better training should be provided for health workers responsible for performing DPP tests applied under field conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

The cost impact of outreach testing and treatment for hepatitis C in an urban Drug Treatment Unit.

PubMed

Selvapatt, Nowlan; Ward, Thomas; Harrison, Lorna; Lombardini, Jody; Thursz, Mark; McEwan, Phil; Brown, Ashley

2017-03-01

In developed countries persons who inject drugs (PWID) represents a significant risk for chronic hepatitis C virus (HCV). It is reported that up to half of persons with chronic HCV remain undiagnosed and reliance on attendance to specialist clinics remain a barrier to treatment. This study assesses the feasibility and cost-effectiveness of outreach screening and treatment within a Drug Treatment Unit (DTU). All persons attending a London DTU were offered HCV testing, and where appropriate follow-up and treatment by a specialist nurse at the DTU. Three years of data informed a cost-effective-analysis using a validated Markov model. A hypothetical scenario in which only direct acting antiviral (DAA) treatments were used was also assessed. Of 321 persons eligible, 216 were screened, 89 were HCV positive and 66 had confirmatory evidence of viraemia. All were infected with either HCV genotype 1 or 3. Treatment was initiated in 29 persons, 22 with interferon based and 7 DAA only regimens. Following initial treatment 21 (72%) achieved SVR12. It is estimated that this programme represents an average per-patient cost-saving of £2498 and a quality-adjusted life year (QALY) gain of 4.10 over a lifetime. In a hypothetical scenario of all oral DAA treatment, an incremental cost per QALY of £1029 was estimated. This study demonstrates feasibility and cost effectiveness of outreach testing and treatment of hepatitis C within comparable DTU settings. Additional costs of newer DAA therapies would not be prohibitive when considering willingness-to-pay thresholds commonly used by policy makers. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A Discrete Event Simulation Model to Assess the Economic Value of a Hypothetical Pharmacogenomics Test for Statin-Induced Myopathy in Patients Initiating a Statin in Secondary Cardiovascular Prevention.

PubMed

Mitchell, Dominic; Guertin, Jason R; Dubois, Anick; Dubé, Marie-Pierre; Tardif, Jean-Claude; Iliza, Ange Christelle; Fanton-Aita, Fiorella; Matteau, Alexis; LeLorier, Jacques

2018-04-01

Statin (HMG-CoA reductase inhibitor) therapy is the mainstay dyslipidemia treatment and reduces the risk of a cardiovascular (CV) event (CVE) by up to 35%. However, adherence to statin therapy is poor. One reason patients discontinue statin therapy is musculoskeletal pain and the associated risk of rhabdomyolysis. Research is ongoing to develop a pharmacogenomics (PGx) test for statin-induced myopathy as an alternative to the current diagnosis method, which relies on creatine kinase levels. The potential economic value of a PGx test for statin-induced myopathy is unknown. We developed a lifetime discrete event simulation (DES) model for patients 65 years of age initiating a statin after a first CVE consisting of either an acute myocardial infarction (AMI) or a stroke. The model evaluates the potential economic value of a hypothetical PGx test for diagnosing statin-induced myopathy. We have assessed the model over the spectrum of test sensitivity and specificity parameters. Our model showed that a strategy with a perfect PGx test had an incremental cost-utility ratio of 4273 Canadian dollars ($Can) per quality-adjusted life year (QALY). The probabilistic sensitivity analysis shows that when the payer willingness-to-pay per QALY reaches $Can12,000, the PGx strategy is favored in 90% of the model simulations. We found that a strategy favoring patients staying on statin therapy is cost effective even if patients maintained on statin are at risk of rhabdomyolysis. Our results are explained by the fact that statins are highly effective in reducing the CV risk in patients at high CV risk, and this benefit largely outweighs the risk of rhabdomyolysis.

Identification of streptococcal proteins reacting with sera from Behçet's disease and rheumatic disorders.

PubMed

Cho, Sung Bin; Lee, Ju Hee; Ahn, Keun Jae; Cho, Suhyun; Park, Yong-Beom; Lee, Soo-Kon; Bang, Dongsik; Lee, Kwang Hoon

2010-01-01

We evaluated the reactivity of sera from Behçet's disease (BD), systemic lupus erythematosus (SLE), dermatomyositis (DM), rheumatoid arthritis (RA), and Takayasu's arteritis (TA) patients against human α-enolase and streptococcal α-enolase, and identified additional streptococcal antigens. Enzyme-linked immunosorbent assay (ELISA) and immunoblotting were performed using sera from patients with BD, SLE, DM, RA, and TA and healthy volunteers (control) against human α-enolase and streptococcal α-enolase. Immunoblot analysis and matrix-assisted laser desorption ionisation-time-of-flight mass spectrometry were used to identify and recombine other streptococcal antigens. Specific positive signals against recombinant human α-enolase were detected by IgM ELISA of serum samples from 50% of BD, 14.3% of SLE, 57.1% of DM, 42.9% of RA, and 57.1% of TA patients. Specific positive signals against streptococcal α-enolase were detected from 42.9% of BD, 14.3% of DM, and 14.3% of TA patients. No SLE and RA sera reacted against streptococcal α-enolase antigen. Streptococcal proteins reacting with sera were identified as hypothetical protein (HP) for SLE and DM patients, acid phosphatase (AP) for RA patients, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for TA patients. We observed that RA patients did not present serum reactivity against either HP or GAPDH though BD, SLE, DM, and TA patients did. Also, AP reacted with sera from BD, SLE, DM, RA, and TA patients.

Transport and Reactive Flow Modelling Using A Particle Tracking Method Based on Continuous Time Random Walks

NASA Astrophysics Data System (ADS)

Oliveira, R.; Bijeljic, B.; Blunt, M. J.; Colbourne, A.; Sederman, A. J.; Mantle, M. D.; Gladden, L. F.

2017-12-01

Mixing and reactive processes have a large impact on the viability of enhanced oil and gas recovery projects that involve acid stimulation and CO2 injection. To achieve a successful design of the injection schemes an accurate understanding of the interplay between pore structure, flow and reactive transport is necessary. Dependent on transport and reactive conditions, this complex coupling can also be dependent on initial rock heterogeneity across a variety of scales. To address these issues, we devise a new method to study transport and reactive flow in porous media at multiple scales. The transport model is based on an efficient Particle Tracking Method based on Continuous Time Random Walks (CTRW-PTM) on a lattice. Transport is modelled using an algorithm described in Rhodes and Blunt (2006) and Srinivasan et al. (2010); this model is expanded to enable for reactive flow predictions in subsurface rock undergoing a first-order fluid/solid chemical reaction. The reaction-induced alteration in fluid/solid interface is accommodated in the model through changes in porosity and flow field, leading to time dependent transport characteristics in the form of transit time distributions which account for rock heterogeneity change. This also enables the study of concentration profiles at the scale of interest. Firstly, we validate transport model by comparing the probability of molecular displacement (propagators) measured by Nuclear Magnetic Resonance (NMR) with our modelled predictions for concentration profiles. The experimental propagators for three different porous media of increasing complexity, a beadpack, a Bentheimer sandstone and a Portland carbonate, show a good agreement with the model. Next, we capture the time evolution of the propagators distribution in a reactive flow experiment, where hydrochloric acid is injected into a limestone rock. We analyse the time-evolving non-Fickian signatures for the transport during reactive flow and observe an increase in transport heterogeneity at latter times, representing the increase in rock heterogeneity. Evolution of transit time distribution is associated with the evolution of concentration profiles, thus highlighting the impact of initial rock structure on the reactive transport for a range of Pe and Da numbers.

Reprioritization of hepatic plasma protein release in trauma and sepsis.

PubMed

Sganga, G; Siegel, J H; Brown, G; Coleman, B; Wiles, C E; Belzberg, H; Wedel, S; Placko, R

1985-02-01

We studied the temporal pattern of seven hepatic synthesized plasma proteins in 26 severely injured patients beginning in the immediate posttrauma period. Clinical sepsis developed in ten patients between three and eight days after injury, and 16 patients had nonseptic courses. In the initial five days after injury, except for albumin, all acute-phase protein levels rose. However, if sepsis developed, C-reactive protein, fibrinogen, ceruloplasmin, and alpha 1-antitrypsin levels continued to be elevated after the initial five posttrauma days, while transferrin, albumin, and alpha 2-macroglobulin levels fell. This differential response became more extreme as sepsis progressed. Covariance analysis of the regression of the five true acute-phase hepatic proteins on C-reactive protein showed that, when sepsis occurred after major traumatic injury, the C-reactive protein rise was associated with a significant reprioritization of hepatic acute-phase plasma protein release. This reprioritization response seems to be both a predictor of sepsis as well as a measure of the adequacy of the host response to trauma and sepsis.

Structure of the Major Apple Allergen Mal d 1

PubMed Central

2017-01-01

More than 70% of birch pollen-allergic patients develop allergic cross-reactions to the major allergen found in apple fruits (Malus domestica), the 17.5 kDa protein Mal d 1. Allergic reactions against this protein result from initial sensitization to the major allergen from birch pollen, Bet v 1. Immunologic cross-reactivity of Bet v 1-specific IgE antibodies with Mal d 1 after apple consumption can subsequently provoke severe oral allergic syndromes. This study presents the three-dimensional NMR solution structure of Mal d 1 (isoform Mal d 1.0101, initially cloned from ‘Granny Smith’ apples). This protein is composed of a seven-stranded antiparallel β-sheet and three α-helices that form a large internal cavity, similar to Bet v 1 and other cross-reactive food allergens. The Mal d 1 structure provides the basis for elucidating the details of allergic cross-reactivity between birch pollen and apple allergens on a molecular level. PMID:28161953

Tracing the fate of ozone in leaves

USDA-ARS?s Scientific Manuscript database

Ozone is a greenhouse gas and considered the most damaging air pollutant to plants. Ozone enters leaves through the stomata, and once in the apoplast, it reacts to produce other reactive oxygen species (ROS) initiating a cellular response. The specific ROS initially formed after ozone exposure and t...

Non-Mendelian Female Sterility in DROSOPHILA MELANOGASTER: Influence of Aging and Thermic Treatments. III. Cumulative Effects Induced by These Factors

PubMed Central

Bucheton, Alain

1979-01-01

Crosses between various strains of Drosophila melanogaster may give rise to a female sterility of non-Mendelian determination. Reduced fertility is observed in females, known as SF females, bred from crosses between females of "reactive" strains and males of "inducer" strains. The reduced fertility of the SF females is the result of an interaction between an extrachromosomal property, the reactivity, and a chromosomal factor, I. The extrachromosomal property varies considerably in its ability to reduce fertility. The fertility reduction of the SF females corresponds to what is known as the reactivity level of their reactive mothers. Two nongenetic factors can modify the level of reactivity: aging and temperature. The action of aging is cumulative. When the flies of a reactive strain are submitted at each generation to the action of this factor, the level of reactivity of this strain is gradually modified. The modifications induced are reversible. Indeed, when such a modified strain is returned to standard breeding conditions, the reactivity returns progressively to its initial level. The effect of thermic treatments also seems to be cumulative and reversible. PMID:121289

What we say and what we do: The relationship between real and hypothetical moral choices

PubMed Central

FeldmanHall, Oriel; Mobbs, Dean; Evans, Davy; Hiscox, Lucy; Navrady, Lauren; Dalgleish, Tim

2012-01-01

Moral ideals are strongly ingrained within society and individuals alike, but actual moral choices are profoundly influenced by tangible rewards and consequences. Across two studies we show that real moral decisions can dramatically contradict moral choices made in hypothetical scenarios (Study 1). However, by systematically enhancing the contextual information available to subjects when addressing a hypothetical moral problem—thereby reducing the opportunity for mental simulation—we were able to incrementally bring subjects’ responses in line with their moral behaviour in real situations (Study 2). These results imply that previous work relying mainly on decontextualized hypothetical scenarios may not accurately reflect moral decisions in everyday life. The findings also shed light on contextual factors that can alter how moral decisions are made, such as the salience of a personal gain. PMID:22405924

Reactivation of Latent Tuberculosis in Cynomolgus Macaques Infected with SIV Is Associated with Early Peripheral T Cell Depletion and Not Virus Load

PubMed Central

Klein, Edwin; Janssen, Chris; Phuah, Jiayao; Sturgeon, Timothy J.; Montelaro, Ronald C.; Lin, Philana Ling; Flynn, JoAnne L.

2010-01-01

HIV-infected individuals with latent Mycobacterium tuberculosis (Mtb) infection are at significantly greater risk of reactivation tuberculosis (TB) than HIV-negative individuals with latent TB, even while CD4 T cell numbers are well preserved. Factors underlying high rates of reactivation are poorly understood and investigative tools are limited. We used cynomolgus macaques with latent TB co-infected with SIVmac251 to develop the first animal model of reactivated TB in HIV-infected humans to better explore these factors. All latent animals developed reactivated TB following SIV infection, with a variable time to reactivation (up to 11 months post-SIV). Reactivation was independent of virus load but correlated with depletion of peripheral T cells during acute SIV infection. Animals experiencing reactivation early after SIV infection (<17 weeks) had fewer CD4 T cells in the periphery and airways than animals reactivating in later phases of SIV infection. Co-infected animals had fewer T cells in involved lungs than SIV-negative animals with active TB despite similar T cell numbers in draining lymph nodes. Granulomas from these animals demonstrated histopathologic characteristics consistent with a chronically active disease process. These results suggest initial T cell depletion may strongly influence outcomes of HIV-Mtb co-infection. PMID:20224771

Reactive pectus carinatum in patients treated for pectus excavatum.

PubMed

Swanson, Jordan W; Colombani, Paul M

2008-08-01

The Ravitch and minimally invasive Nuss procedures have brought widespread relief to children with pectus excavatum, chest wall deformities, over the last half century. Generally accepted long-term complications of pectus excavatum repair are typically limited to recurrence of the excavatum deformity or persistent pain. This study examines the authors' experience with patients who develop a subsequent carinatum deformity within 1 year of pectus excavatum repair. The authors retrospectively assessed the charts of all patients diagnosed as having a carinatum deformity subsequent to treatment for pectus excavatum at a tertiary urban hospital. We noted age at original correction of pectus excavatum, time from original correction to diagnosis of carinatum deformity, age at correction of carinatum deformity, complaints before correction, methods of repair, postoperative complications, and we reviewed relevant radiography. Three patients who underwent pectus excavatum repair between January 2000 and August 2007 developed a subsequent carinatum deformity. Two patients initially underwent minimally invasive Nuss correction of pectus excavatum; 1 patient underwent the Ravitch procedure. Within 1 year of original correction and despite intraoperative achievement of neutral sternal position, a protruding anterior chest deformity resembling de novo pectus carinatum emerged in each patient; we term this condition reactive pectus carinatum. The mean age of patients undergoing initial pectus excavatum repair was 13 years (range, 11-16 years). The pathophysiology of this reactive lesion is not well understood but is thought to originate from reactive fibroblastic stimulation as a result of sternal manipulation and bar placement. Patients who underwent Nuss correction initially were managed with early bar removal. Two of the patients eventually required surgical resection of the carinatum deformity at a time interval of 3 to 6 years after initial excavatum repair. In one patient, the carinatum deformity resolved spontaneously. Neutral chest position and absence of dyspenic symptoms were achieved in all patients. Reactive pectus carinatum is functionally encumbering and a poor cosmetic complication of either the Ravitch or minimally invasive Nuss procedures. Our experience with reactive pectus carinatum introduces the importance of postoperative vigilance even in patients without underlying fibroelastic disease. Examination of the chest with attention to the possibility of an emerging carinatum deformity, particularly in the first 6 postoperative months, is paramount. A telephone call to the patient at 3 months may be a useful adjunct to clinic visits. An optimal long-term result may be achieved through a combination of early Nuss bar removal or postpubertal pectus carinatum repair.

Plane wave packet formulation of atom-plus-diatom quantum reactive scattering.

PubMed

Althorpe, Stuart C

2004-07-15

We recently interpreted several reactive scattering experiments using a plane wave packet (PWP) formulation of quantum scattering theory [see, e.g., S. C. Althorpe, F. Fernandez-Alonso, B. D. Bean, J. D. Ayers, A. E. Pomerantz, R. N. Zare, and E. Wrede, Nature (London) 416, 67 (2002)]. This paper presents the first derivation of this formulation for atom-plus-diatom reactive scattering, and explains its relation to conventional time-independent reactive scattering. We generalize recent results for spherical-particle scattering [S. C. Althorpe, Phys. Rev. A 69, 042702 (2004)] to atom-rigid-rotor scattering in the space-fixed frame, atom-rigid-rotor scattering in the body-fixed frame, and finally A+BC rearrangement scattering. The reactive scattering is initiated by a plane wave packet, describing the A+BC reagents in center-of-mass scattering coordinates, and is detected by projecting onto a series of AC+B (or AB+C) plane wave "probe" packets. The plane wave packets are localized at the closest distance from the scattering center at which the interaction potential can be neglected. The time evolution of the initial plane wave packet provides a clear visualization of the scattering into space of the reaction products. The projection onto the probe packets yields the time-independent, state-to-state scattering amplitude, and hence the differential cross section. We explain how best to implement the PWP approach in a numerical computation, and illustrate this with a detailed application to the H+D2 reaction. (c) 2004 American Institute of Physics

Cr(VI)-contaminated groundwater remediation with simulated permeable reactive barrier (PRB) filled with natural pyrite as reactive material: Environmental factors and effectiveness.

PubMed

Liu, Yuanyuan; Mou, Haiyan; Chen, Liqun; Mirza, Zakaria A; Liu, Li

2015-11-15

Permeable reactive barriers (PRBs) are efficient technologies for in situ remediation of contaminated groundwater, the effectiveness of which greatly depends on the reactive media filled. Natural pyrite is an iron sulfide material with a very low content of iron and sulfur, and a mining waste which is a potential material for Cr(VI) immobilization. In this study, we conducted a series of batch tests to research the effects of typical environmental factors on Cr(VI) removal and also simulated PRB filled with natural pyrite to investigate its effectiveness, in order to find a both environmentally and economically fine method for groundwater remediation. Batch tests showed that pH had the significant impact on Cr(VI) removal with an apparently higher efficiency under acidic conditions, and dissolved oxygen (DO) would inhibit Cr(VI) reduction; a relatively high initial Cr(VI) concentration would decrease the rate of Cr(VI) sorption; ionic strength and natural organic matter resulted in no significant effects on Cr(VI) removal. Column tests demonstrated that the simulated PRB with natural pyrite as the reactive media was considerably effective for removing Cr(VI) from groundwater, with a sorption capability of 0.6222 mg Cr per gram of natural pyrite at an initial Cr(VI) concentration of 10mg/L at pH 5.5 in an anoxic environment. Copyright © 2015 Elsevier B.V. All rights reserved.

Optimization of degradation of Reactive Black 5 (RB5) and electricity generation in solar photocatalytic fuel cell system.

PubMed

Khalik, Wan Fadhilah; Ho, Li-Ngee; Ong, Soon-An; Voon, Chun-Hong; Wong, Yee-Shian; Yusoff, NikAthirah; Lee, Sin-Li; Yusuf, Sara Yasina

2017-10-01

The photocatalytic fuel cell (PFC) system was developed in order to study the effect of several operating parameters in degradation of Reactive Black 5 (RB5) and its electricity generation. Light irradiation, initial dye concentration, aeration, pH and cathode electrode are the operating parameters that might give contribution in the efficiency of PFC system. The degradation of RB5 depends on the presence of light irradiation and solar light gives better performance to degrade the azo dye. The azo dye with low initial concentration decolorizes faster compared to higher initial concentration and presence of aeration in PFC system would enhance its performance. Reactive Black 5 rapidly decreased at higher pH due to the higher amount of OH generated at higher pH and Pt-loaded carbon (Pt/C) was more suitable to be used as cathode in PFC system compared to Cu foil and Fe foil. The rapid decolorization of RB5 would increase their voltage output and in addition, it would also increase their V oc , J sc and P max . The breakage of azo bond and aromatic rings was confirmed through UV-Vis spectrum and COD analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

A simulation model to estimate the cost and effectiveness of alternative dialysis initiation strategies.

PubMed

Lee, Chris P; Chertow, Glenn M; Zenios, Stefanos A

2006-01-01

Patients with end-stage renal disease (ESRD) require dialysis to maintain survival. The optimal timing of dialysis initiation in terms of cost-effectiveness has not been established. We developed a simulation model of individuals progressing towards ESRD and requiring dialysis. It can be used to analyze dialysis strategies and scenarios. It was embedded in an optimization frame worked to derive improved strategies. Actual (historical) and simulated survival curves and hospitalization rates were virtually indistinguishable. The model overestimated transplantation costs (10%) but it was related to confounding by Medicare coverage. To assess the model's robustness, we examined several dialysis strategies while input parameters were perturbed. Under all 38 scenarios, relative rankings remained unchanged. An improved policy for a hypothetical patient was derived using an optimization algorithm. The model produces reliable results and is robust. It enables the cost-effectiveness analysis of dialysis strategies.

Optimal Design for Placements of Tsunami Observing Systems to Accurately Characterize the Inducing Earthquake

NASA Astrophysics Data System (ADS)

Mulia, Iyan E.; Gusman, Aditya Riadi; Satake, Kenji

2017-12-01

Recently, there are numerous tsunami observation networks deployed in several major tsunamigenic regions. However, guidance on where to optimally place the measurement devices is limited. This study presents a methodological approach to select strategic observation locations for the purpose of tsunami source characterizations, particularly in terms of the fault slip distribution. Initially, we identify favorable locations and determine the initial number of observations. These locations are selected based on extrema of empirical orthogonal function (EOF) spatial modes. To further improve the accuracy, we apply an optimization algorithm called a mesh adaptive direct search to remove redundant measurement locations from the EOF-generated points. We test the proposed approach using multiple hypothetical tsunami sources around the Nankai Trough, Japan. The results suggest that the optimized observation points can produce more accurate fault slip estimates with considerably less number of observations compared to the existing tsunami observation networks.

Long-Term Obliquity Variations of a Moonless Earth

NASA Astrophysics Data System (ADS)

Barnes, Jason W.; Lissauer, J. J.; Chambers, J. E.

2012-05-01

Earth's present-day obliquity varies by +/-1.2 degrees over 100,000-year timescales. Without the Moon's gravity increasing the rotation axis precession rate, prior theory predicted that a moonless Earth's obliquity would be allowed to vary between 0 and 85 degrees -- moreso even than present-day Mars (0 - 60 degrees). We use a modified version of the symplectic orbital integrator `mercury' to numerically investigate the obliquity evolution of hypothetical moonless Earths. Contrary to the large theoretically allowed range, we find that moonless Earths more typically experience obliquity variations of just +/- 10 degrees over Gyr timescales. Some initial conditions for the moonless Earth's rotation rate and obliquity yield slightly greater variations, but the majority have smaller variations. In particular, retrograde rotators are quite stable and should constitute 50% of the population if initial terrestrial planet rotation is isotropic. Our results have important implications for the prospects of long-term habitability of moonless planets in extrasolar systems.

Large-Scale Reactive Atomistic Simulation of Shock-induced Initiation Processes in Energetic Materials

NASA Astrophysics Data System (ADS)

Thompson, Aidan

2013-06-01

Initiation in energetic materials is fundamentally dependent on the interaction between a host of complex chemical and mechanical processes, occurring on scales ranging from intramolecular vibrations through molecular crystal plasticity up to hydrodynamic phenomena at the mesoscale. A variety of methods (e.g. quantum electronic structure methods (QM), non-reactive classical molecular dynamics (MD), mesoscopic continuum mechanics) exist to study processes occurring on each of these scales in isolation, but cannot describe how these processes interact with each other. In contrast, the ReaxFF reactive force field, implemented in the LAMMPS parallel MD code, allows us to routinely perform multimillion-atom reactive MD simulations of shock-induced initiation in a variety of energetic materials. This is done either by explicitly driving a shock-wave through the structure (NEMD) or by imposing thermodynamic constraints on the collective dynamics of the simulation cell e.g. using the Multiscale Shock Technique (MSST). These MD simulations allow us to directly observe how energy is transferred from the shockwave into other processes, including intramolecular vibrational modes, plastic deformation of the crystal, and hydrodynamic jetting at interfaces. These processes in turn cause thermal excitation of chemical bonds leading to initial chemical reactions, and ultimately to exothermic formation of product species. Results will be presented on the application of this approach to several important energetic materials, including pentaerythritol tetranitrate (PETN) and ammonium nitrate/fuel oil (ANFO). In both cases, we validate the ReaxFF parameterizations against QM and experimental data. For PETN, we observe initiation occurring via different chemical pathways, depending on the shock direction. For PETN containing spherical voids, we observe enhanced sensitivity due to jetting, void collapse, and hotspot formation, with sensitivity increasing with void size. For ANFO, we examine the effect of reaction rates on shock direction, fuel oil fraction, and crystal/fuel oil/void microstructural arrangement. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Dept. of Energy's National Nuclear Security Admin. under contract DEAC0494AL85000.

A clinician-administered observation and corresponding caregiver interview capturing DSM-5 sensory reactivity symptoms in children with ASD.

PubMed

Siper, Paige M; Kolevzon, Alexander; Wang, A Ting; Buxbaum, Joseph D; Tavassoli, Teresa

2017-06-01

Sensory reactivity is a new criterion for autism spectrum disorder (ASD) in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). However, there is no consensus on how to reliably measure sensory reactivity, particularly in minimally verbal individuals. The current study is an initial validation of the Sensory Assessment for Neurodevelopmental Disorders (SAND), a novel clinician-administered observation and corresponding caregiver interview that captures sensory symptoms based on DSM-5 criteria for ASD. Eighty children between the ages of 2 and 12 participated in this study; 44 children with ASD and 36 typically developing (TD) children. Sensory reactivity symptoms were measured using the SAND and the already validated Short Sensory Profile (SSP). Initial psychometric properties of the SAND were examined including reliability, validity, sensitivity and specificity. Children with ASD showed significantly more sensory reactivity symptoms compared to TD children across sensory domains (visual, tactile, and auditory) and within sensory subtypes (hyperreactivity, hyporeactivity and seeking). The SAND showed strong internal consistency, inter-rater reliability and test-retest reliability, high sensitivity (95.5%) and specificity (91.7%), and strong convergent validity with the SSP. The SAND provides a novel method to characterize sensory reactivity symptoms based on DSM-5 criteria for ASD. This is the first known sensory assessment that combines a clinician-administered observation and caregiver interview to optimally capture sensory phenotypes characteristic of individuals with neurodevelopmental disorders. The SAND offers a beneficial new tool for both research and clinical purposes and has the potential to meaningfully enhance gold-standard assessment of ASD. Autism Res 2017, 10: 1133-1140. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Comparison of turnaround time and total cost of HIV testing before and after implementation of the 2014 CDC/APHL Laboratory Testing Algorithm for diagnosis of HIV infection.

PubMed

Chen, Derrick J; Yao, Joseph D

2017-06-01

Updated recommendations for HIV diagnostic laboratory testing published by the Centers for Disease Control and Prevention and the Association of Public Health Laboratories incorporate 4th generation HIV immunoassays, which are capable of identifying HIV infection prior to seroconversion. The purpose of this study was to compare turnaround time and cost between 3rd and 4th generation HIV immunoassay-based testing algorithms for initially reactive results. The clinical microbiology laboratory database at Mayo Clinic, Rochester, MN was queried for 3rd generation (from November 2012 to May 2014) and 4th generation (from May 2014 to November 2015) HIV immunoassay results. All results from downstream supplemental testing were recorded. Turnaround time (defined as the time of initial sample receipt in the laboratory to the time the final supplemental test in the algorithm was resulted) and cost (based on 2016 Medicare reimbursement rates) were assessed. A total of 76,454 and 78,998 initial tests were performed during the study period using the 3rd generation and 4th generation HIV immunoassays, respectively. There were 516 (0.7%) and 581 (0.7%) total initially reactive results, respectively. Of these, 304 (58.9%) and 457 (78.7%) were positive by supplemental testing. There were 10 (0.01%) cases of acute HIV infection identified with the 4th generation algorithm. The most frequent tests performed to confirm an HIV-positive case using the 3rd generation algorithm, which were reactive initial immunoassay and positive HIV-1 Western blot, took a median time of 1.1 days to complete at a cost of $45.00. In contrast, the most frequent tests performed to confirm an HIV-positive case using the 4th generation algorithm, which included a reactive initial immunoassay and positive HIV-1/-2 antibody differentiation immunoassay for HIV-1, took a median time of 0.4 days and cost $63.25. Overall median turnaround time was 2.2 and 1.5 days, and overall median cost was $63.90 and $72.50 for 3rd and 4th generation algorithms, respectively. Both 3rd and 4th generation HIV immunoassays had similar total numbers of tests performed and positivity rates during the study period. A greater proportion of reactive 4th generation immunoassays were confirmed to be positive, and the 4th generation algorithm identified several cases of acute HIV infection that would have been missed by the 3rd generation algorithm. The 4th generation algorithm had a more rapid turnaround time but higher cost for confirmed positive HIV infections and overall, compared to the 3rd generation algorithm. Copyright © 2017 Elsevier B.V. All rights reserved.

Diversity-oriented synthesis leads to an effective class of bifunctional linchpins uniting anion relay chemistry (ARC) with benzyne reactivity

PubMed Central

Smith, Amos B.; Kim, Won-Suk

2011-01-01

In conjunction with the construction of a diversity-oriented synthesis library of 10-membered ring “natural product-like” macrolides, the design, synthesis, and validation of a unique class of bifunctional linchpins, uniting benzyne reactivity initiated by type II anion relay chemistry (ARC) has been achieved, permitting access to diverse [2+2], [3+2], and [4+2] cycloadducts. PMID:21245309

Quantum and quasi-classical calculations for the S+ + H2(v, j) →SH+(v′, j′)+H reactive collisions

PubMed Central

Zanchet, Alexandre; Roncero, Octavio; Bulut, Niyazi

2016-01-01

State-to-state cross sections for the S+ + H2(v, j) → SH+ (v′, j′) + H endothermic reaction are obtained with quantum wave packet(WP) and quasi-classical (QCT) methods for different initial rovibrational H2(v, j) over a wide range of translation energies. Final state distribution as a function of the initial quantum number is obtained and discussed. Additionally, the effect of the internal excitation of H2 on the reactivity is carefully studied. It appears that energy transfer among modes is very inefficient, that vibrational energy is the most favorable for reaction and rotational excitation significantly enhance reactivity when vibrational energy is sufficient to reach the product. Special attention is also paid on an unusual discrepancy between classical and quantum dynamics for low rotational levels while agreement improves with rotational excitation of H2, An interesting resonant behaviour found in WP calculations is also discussed and is associated to the existence of roaming classical trajectories that enhance the reactivity of the title reaction. Finally, a comparison with the experimental results of Stowe et al.[1] for S+ + HD and S+ +D2 reactions, finding a reasonably good agreement with those results. PMID:27055725

Quantum and quasi-classical calculations for the S⁺ + H₂(v,j) → SH⁺(v',j') + H reactive collisions.

PubMed

Zanchet, Alexandre; Roncero, Octavio; Bulut, Niyazi

2016-04-28

State-to-state cross-sections for the S(+) + H2(v,j) → SH(+)(v',j') + H endothermic reaction are obtained using quantum wave packet (WP) and quasi-classical (QCT) methods for different initial ro-vibrational H2(v,j) over a wide range of translation energies. The final state distribution as a function of the initial quantum number is obtained and discussed. Additionally, the effect of the internal excitation of H2 on the reactivity is carefully studied. It appears that energy transfer among modes is very inefficient that vibrational energy is the most favorable for the reaction, and rotational excitation significantly enhances the reactivity when vibrational energy is sufficient to reach the product. Special attention is also paid to an unusual discrepancy between classical and quantum dynamics for low rotational levels while agreement improves with rotational excitation of H2. An interesting resonant behaviour found in WP calculations is also discussed and associated with the existence of roaming classical trajectories that enhance the reactivity of the title reaction. Finally, a comparison with the experimental results of Stowe et al. for S(+) + HD and S(+) + D2 reactions exhibits a reasonably good agreement with those results.

Characterization of tannery sludge activated carbon and its utilization in the removal of azo reactive dye.

PubMed

Geethakarthi, A; Phanikumar, B R

2012-03-01

The removal of azo Reactive Red 31(RR31) from synthetic dye solution using tannery sludge-developed activated carbon (TSC) was investigated. TSC was prepared from a combination of physical and chemical activation. The developed TSC was characterized by FT-IR, SEM, TG-DTA, specific surface area and zero point charge of pH (pH(zpc)). The isotherm models, kinetic models and thermodynamic parameters were also analysed to describe the adsorptive behaviour of TSC. The effect of contact time, initial dye concentration, carbon dosage, agitation speed, initial pH and temperature were carried out for batch adsorption studies. The isotherm plot of the dye RR31 on TSC fitted better with the Langmuir adsorption isotherm than the Freundlich model. The maximum monolayer adsorption capacity of TSC in the removal of RR31 ranged from 23.15 to 39.37 mg/g. The thermodynamic parameters showed the endothermic and physical nature of the Reactive Red 31 adsorption on TSC. The entropy and enthalpy values were 181.515 J/Kmol and 5.285 kJ/mol, respectively. The developed cationic tannery sludge carbon was found to be an effective adsorbent in the removal of the anionic azo reactive dye RR31.

Modeling the Shock Ignition of a Copper Oxide Aluminum Thermite

NASA Astrophysics Data System (ADS)

Lee, Kibaek; Stewart, D. Scott; Clemenson, Michael; Glumac, Nick; Murzyn, Christopher

2015-06-01

An experimental ``striker confinement'' shock compression test was developed in the Glumac-group at the University of Illinois to study ignition and reaction in composite reactive materials. These include thermitic and intermetallic reactive powders. The test places a sample of materials such as a thermite mixture of copper oxide and aluminum powders that are initially compressed to about 80 percent full density. Two RP-80 detonators simultaneously push steel bars into reactive material and the resulting compression causes shock compaction of the material and rapid heating. At that point one observes significant reaction and propagation of fronts. But the fronts are peculiar in that they are comprised of reactive events that can be traced to the reaction/diffusion of the initially separated reactants of copper oxide and aluminum that react at their mutual interfaces that nominally make copper liquid and aluminum oxide products. We discuss our model of the shock ignition of the copper oxide aluminum thermite in the context of the striker experiment and how a Gibbs formulation model, that includes multi-components for liquid and solid phases of aluminum, copper oxide, copper and aluminum oxide can predict the events observed at the particle scale in the experiments. Supported by HDTRA1-10-1-0020 (DTRA), N000014-12-1-0555 (ONR).

Influence of crystallised igneous intrusions on fault nucleation and reactivation during continental extension

NASA Astrophysics Data System (ADS)

Magee, Craig; McDermott, Kenneth G.; Stevenson, Carl T. E.; Jackson, Christopher A.-L.

2014-05-01

Continental rifting is commonly accommodated by the nucleation of normal faults, slip on pre-existing fault surfaces and/or magmatic intrusion. Because crystallised igneous intrusions are pervasive in many rift basins and are commonly more competent (i.e. higher shear strengths and Young's moduli) than the host rock, it is theoretically plausible that they locally intersect and modify the mechanical properties of pre-existing normal faults. We illustrate the influence that crystallised igneous intrusions may have on fault reactivation using a conceptual model and observations from field and subsurface datasets. Our results show that igneous rocks may initially resist failure, and promote the preferential reactivation of favourably-oriented, pre-existing faults that are not spatially-associated with solidified intrusions. Fault segments situated along strike from laterally restricted fault-intrusion intersections may similarly be reactivated. This spatial and temporal control on strain distribution may generate: (1) supra-intrusion folds in the hanging wall; (2) new dip-slip faults adjacent to the igneous body; or (3) sub-vertical, oblique-slip faults oriented parallel to the extension direction. Importantly, stress accumulation within igneous intrusions may eventually initiate failure and further localise strain. The results of our study have important implications for the structural of sedimentary basins and the subsurface migration of hydrocarbons and mineral-bearing fluids.

Human Health Effects of Ozone Depletion From Stratospheric Aircraft

NASA Technical Reports Server (NTRS)

Wey, Chowen (Technical Monitor)

2001-01-01

This report presents EPA's initial response to NASA's request to advise on potential environmental policy issues associated with the future development of supersonic flight technologies. Consistent with the scope of the study to which NASA and EPA agreed, EPA has evaluated only the environmental concerns related to the stratospheric ozone impacts of a hypothetical HSCT fleet, although recent research indicates that a fleet of HSCT is predicted to contribute to climate warming as well. This report also briefly describes the international and domestic institutional frameworks established to address stratospheric ozone depletion, as well as those established to control pollution from aircraft engine exhaust emissions.

The surface geometry of inherited joint and fracture trace patterns resulting from active and passive deformation

NASA Technical Reports Server (NTRS)

Podwysocki, M. H.; Gold, D. P.

1974-01-01

Hypothetical models are considered for detecting subsurface structure from the fracture or joint pattern, which may be influenced by the structure and propagated to the surface. Various patterns of an initially orthogonal fracture grid are modeled according to active and passive deformation mechanisms. In the active periclinal structure with a vertical axis, fracture frequency increased both over the dome and basin, and remained constant with decreasing depth to the structure. For passive periclinal features such as a reef or sand body, fracture frequency is determined by the arc of curvature and showed a reduction over the reefmound and increased over the basin.

Two approaches to the rapid screening of crystallization conditions

NASA Technical Reports Server (NTRS)

Mcpherson, Alexander

1992-01-01

A screening procedure is described for estimating conditions under which crystallization will proceed, thus providing a starting point for more careful experiments. The initial procedure uses the experimental setup of McPherson (1982) which supports 24 individual hanging drop experiments for screening variables such as the precipitant type, the pH, the temperature, and the effects of certain additives and which uses about 1 mg of protein. A second approach is proposed (which is rather hypothetical at this stage and needs a larger sample), based on the isoelectric focusing of protein samples on concentration gradients of common precipitating agents. Using this approach, crystals of concanavalin B and canavalin were obtained.

Evaluating remedial alternatives for an acid mine drainage stream: Application of a reactive transport model

USGS Publications Warehouse

Runkel, R.L.; Kimball, B.A.

2002-01-01

A reactive transport model based on one-dimensional transport and equilibrium chemistry is applied to synoptic data from an acid mine drainage stream. Model inputs include streamflow estimates based on tracer dilution, inflow chemistry based on synoptic sampling, and equilibrium constants describing acid/base, complexation, precipitation/dissolution, and sorption reactions. The dominant features of observed spatial profiles in pH and metal concentration are reproduced along the 3.5-km study reach by simulating the precipitation of Fe(III) and Al solid phases and the sorption of Cu, As, and Pb onto freshly precipitated iron-(III) oxides. Given this quantitative description of existing conditions, additional simulations are conducted to estimate the streamwater quality that could result from two hypothetical remediation plans. Both remediation plans involve the addition of CaCO3 to raise the pH of a small, acidic inflow from ???2.4 to ???7.0. This pH increase results in a reduced metal load that is routed downstream by the reactive transport model, thereby providing an estimate of post-remediation water quality. The first remediation plan assumes a closed system wherein inflow Fe(II) is not oxidized by the treatment system; under the second remediation plan, an open system is assumed, and Fe(II) is oxidized within the treatment system. Both plans increase instream pH and substantially reduce total and dissolved concentrations of Al, As, Cu, and Fe(II+III) at the terminus of the study reach. Dissolved Pb concentrations are reduced by ???18% under the first remediation plan due to sorption onto iron-(III) oxides within the treatment system and stream channel. In contrast, iron(III) oxides are limiting under the second remediation plan, and removal of dissolved Pb occurs primarily within the treatment system. This limitation results in an increase in dissolved Pb concentrations over existing conditions as additional downstream sources of Pb are not attenuated by sorption.

Perceptions of, and assistance provided to, a hypothetical rape victim: differences between rape disclosure recipients and nonrecipients.

PubMed

Paul, Lisa A; Kehn, Andre; Gray, Matt J; Salapska-Gelleri, Joanna

2014-01-01

Undergraduate rape disclosure recipients' and nonrecipients' sociodemographic and life experience variables, attitudes towards rape, and responses to a hypothetical rape disclosure were compared to determine differences between them. One hundred ninety-two undergraduates at 3 universities participated in this online survey between November 2011 and April 2012. Participants reported on their rape myth acceptance (RMA) and personal direct and indirect (ie, disclosure receipt) experiences with sexual assault. Participants also responded to a hypothetical rape disclosure. Disclosure recipients were more likely to report a victimization history, and less confusion and perceived ineffectiveness in helping the hypothetical victim. RMA and nonrecipient status predicted perceived victim responsibility; these variables and childhood victimization predicted confusion about helping. RMA also predicted perceived ineffectiveness of one's helping behaviors. Victimization history and female gender predicted victim empathy. These findings can inform sexual assault-related programming for undergraduates through the provision of targeted assistance and corrective information.

What we say and what we do: the relationship between real and hypothetical moral choices.

PubMed

FeldmanHall, Oriel; Mobbs, Dean; Evans, Davy; Hiscox, Lucy; Navrady, Lauren; Dalgleish, Tim

2012-06-01

Moral ideals are strongly ingrained within society and individuals alike, but actual moral choices are profoundly influenced by tangible rewards and consequences. Across two studies we show that real moral decisions can dramatically contradict moral choices made in hypothetical scenarios (Study 1). However, by systematically enhancing the contextual information available to subjects when addressing a hypothetical moral problem-thereby reducing the opportunity for mental simulation-we were able to incrementally bring subjects' responses in line with their moral behaviour in real situations (Study 2). These results imply that previous work relying mainly on decontextualized hypothetical scenarios may not accurately reflect moral decisions in everyday life. The findings also shed light on contextual factors that can alter how moral decisions are made, such as the salience of a personal gain. Copyright © 2012 Elsevier B.V. All rights reserved.

Frictional and hydraulic behaviour of carbonate fault gouge during fault reactivation - An experimental study

NASA Astrophysics Data System (ADS)

Delle Piane, Claudio; Giwelli, Ausama; Clennell, M. Ben; Esteban, Lionel; Nogueira Kiewiet, Melissa Cristina D.; Kiewiet, Leigh; Kager, Shane; Raimon, John

2016-10-01

We present a novel experimental approach devised to test the hydro-mechanical behaviour of different structural elements of carbonate fault rocks during experimental re-activation. Experimentally faulted core plugs were subject to triaxial tests under water saturated conditions simulating depletion processes in reservoirs. Different fault zone structural elements were created by shearing initially intact travertine blocks (nominal size: 240 × 110 × 150 mm) to a maximum displacement of 20 and 120 mm under different normal stresses. Meso-and microstructural features of these sample and the thickness to displacement ratio characteristics of their deformation zones allowed to classify them as experimentally created damage zones (displacement of 20 mm) and fault cores (displacement of 120 mm). Following direct shear testing, cylindrical plugs with diameter of 38 mm were drilled across the slip surface to be re-activated in a conventional triaxial configuration monitoring the permeability and frictional behaviour of the samples as a function of applied stress. All re-activation experiments on faulted plugs showed consistent frictional response consisting of an initial fast hardening followed by apparent yield up to a friction coefficient of approximately 0.6 attained at around 2 mm of displacement. Permeability in the re-activation experiments shows exponential decay with increasing mean effective stress. The rate of permeability decline with mean effective stress is higher in the fault core plugs than in the simulated damage zone ones. It can be concluded that the presence of gouge in un-cemented carbonate faults results in their sealing character and that leakage cannot be achieved by renewed movement on the fault plane alone, at least not within the range of slip measureable with our apparatus (i.e. approximately 7 mm of cumulative displacement). Additionally, it is shown that under sub seismic slip rates re-activated carbonate faults remain strong and no frictional weakening was observed during re-activation.

In vitro Reactivity to Implant Metals Demonstrates a Person Dependent Association with both T-Cell and B-Cell Activation

PubMed Central

Hallab, Nadim James; Caicedo, Marco; Epstein, Rachael; McAllister, Kyron; Jacobs, Joshua J

2009-01-01

Hypersensitivity to metallic implants remains relatively unpredictable and poorly understood. We initially hypothesized that metal-induced lymphocyte proliferation responses to soluble metal challenge (ions) are mediated exclusively by early T-cell activation (not B-cells), typical of a Delayed-Type-Hypersensitivity response. We tested this by comparing proliferation (6-days) of primary lymphocytes with early T-cell and B-cell activation (48-hours) in three groups of subjects likely to demonstrate elevated metal-reactivity: Group 1(n=12) history of metal-sensitivity with no implant; Group 2a(n=6) well performing metal-on-metal THRs, and Group 2b(n=20) subjects with poorly performing metal-on-polymer total joint arthroplasties (TJA). Group 1 showed 100%(12/12) metal reactivity (Stimulation Index>2) to Ni. Group 2a&2b were 83%(5/6) and 75%(15/22) metal reactive (to Co, Cr or Ni) respectively. Of the n=32 metal reactive subjects to Co, Cr or Ni (SI>2), n=22/32 demonstrated >2-fold elevations in % of T-cell or B-cell activation (CD25+,CD69+) to metal challenge compared to untreated control. 18/22 metal-activated subjects demonstrated an exclusively T-cell or B-cell activation response to metal challenge, where 6/18 demonstrated exclusively B-cell activation and 12/18 demonstrated a T-cell only response, as measured by surface activation markers CD25+ and CD69+. However, there was no direct correlation (R2<0.1) between lymphocyte proliferation and % T-cell or B-cell activation (CD25+:CD69+). Proliferation assays (LTT) showed greater ability to detect metal reactivity than did subject-dependent results of flow-cytometry analysis of T-cell or B-cell activation. The high incidence of lymphocyte reactivity and activation, indicate that more complex than initially hypothesized immune responses may contribute to the etiology of debris induced osteolysis in metal-sensitive individuals. PMID:19235773

Effects of Biologic Agents in Patients with Rheumatoid Arthritis and Amyloidosis Treated with Hemodialysis.

PubMed

Kuroda, Takeshi; Tanabe, Naohito; Nozawa, Yukiko; Sato, Hiroe; Nakatsue, Takeshi; Kobayashi, Daisuke; Wada, Yoko; Saeki, Takako; Nakano, Masaaki; Narita, Ichiei

Objective Our objective was to examine the safety and effects of therapy with biologics on the prognosis of rheumatoid arthritis (RA) patients with reactive amyloid A (AA) amyloidosis on hemodialysis (HD). Methods Twenty-eight patients with an established diagnosis of reactive AA amyloidosis participated in the study. The survival was calculated from the date of HD initiation until the time of death, or up to end of June 2015 for the patients who were still alive. HD initiation was according to the program of HD initiation for systemic amyloidosis patients associated with RA. Results Ten patients had been treated with biologics before HD initiation for a mean of 28.2 months (biologic group), while 18 had not (non-biologic group). HD was initiated in patients with similar characteristics except for the tender joint count, swollen joint count, and disease activity score (DAS)28-C-reactive protein (CRP). History of biologics showed that etanercept was frequently used for 8 patients as the first biologic. There was no significant difference in the mortality rate according to a Kaplan-Meier analysis (p=0.939) and or associated risk of death in an age-adjusted Cox proportional hazards model (p=0.758) between both groups. Infections were significantly more frequent causes of death in the biologic group than in the non-biologic group (p=0.021). However, treatment with biologics improved the DAS28-CRP score (p=0.004). Conclusion Under the limited conditions of AA amyloidosis treated with HD, the use of biologics might affect infection and thus may not improve the prognosis. Strict infection control is necessary for the use of biologics with HD to improve the prognosis.

Effects of Biologic Agents in Patients with Rheumatoid Arthritis and Amyloidosis Treated with Hemodialysis

PubMed Central

Kuroda, Takeshi; Tanabe, Naohito; Nozawa, Yukiko; Sato, Hiroe; Nakatsue, Takeshi; Kobayashi, Daisuke; Wada, Yoko; Saeki, Takako; Nakano, Masaaki; Narita, Ichiei

2016-01-01

Objective Our objective was to examine the safety and effects of therapy with biologics on the prognosis of rheumatoid arthritis (RA) patients with reactive amyloid A (AA) amyloidosis on hemodialysis (HD). Methods Twenty-eight patients with an established diagnosis of reactive AA amyloidosis participated in the study. The survival was calculated from the date of HD initiation until the time of death, or up to end of June 2015 for the patients who were still alive. HD initiation was according to the program of HD initiation for systemic amyloidosis patients associated with RA. Results Ten patients had been treated with biologics before HD initiation for a mean of 28.2 months (biologic group), while 18 had not (non-biologic group). HD was initiated in patients with similar characteristics except for the tender joint count, swollen joint count, and disease activity score (DAS)28-C-reactive protein (CRP). History of biologics showed that etanercept was frequently used for 8 patients as the first biologic. There was no significant difference in the mortality rate according to a Kaplan-Meier analysis (p=0.939) and or associated risk of death in an age-adjusted Cox proportional hazards model (p=0.758) between both groups. Infections were significantly more frequent causes of death in the biologic group than in the non-biologic group (p=0.021). However, treatment with biologics improved the DAS28-CRP score (p=0.004). Conclusion Under the limited conditions of AA amyloidosis treated with HD, the use of biologics might affect infection and thus may not improve the prognosis. Strict infection control is necessary for the use of biologics with HD to improve the prognosis. PMID:27725536

Atmospheric transport of radioactive debris to Norway in case of a hypothetical accident related to the recovery of the Russian submarine K-27.

PubMed

Bartnicki, Jerzy; Amundsen, Ingar; Brown, Justin; Hosseini, Ali; Hov, Øystein; Haakenstad, Hilde; Klein, Heiko; Lind, Ole Christian; Salbu, Brit; Szacinski Wendel, Cato C; Ytre-Eide, Martin Album

2016-01-01

The Russian nuclear submarine K-27 suffered a loss of coolant accident in 1968 and with nuclear fuel in both reactors it was scuttled in 1981 in the outer part of Stepovogo Bay located on the eastern coast of Novaya Zemlya. The inventory of spent nuclear fuel on board the submarine is of concern because it represents a potential source of radioactive contamination of the Kara Sea and a criticality accident with potential for long-range atmospheric transport of radioactive particles cannot be ruled out. To address these concerns and to provide a better basis for evaluating possible radiological impacts of potential releases in case a salvage operation is initiated, we assessed the atmospheric transport of radionuclides and deposition in Norway from a hypothetical criticality accident on board the K-27. To achieve this, a long term (33 years) meteorological database has been prepared and used for selection of the worst case meteorological scenarios for each of three selected locations of the potential accident. Next, the dispersion model SNAP was run with the source term for the worst-case accident scenario and selected meteorological scenarios. The results showed predictions to be very sensitive to the estimation of the source term for the worst-case accident and especially to the sizes and densities of released radioactive particles. The results indicated that a large area of Norway could be affected, but that the deposition in Northern Norway would be considerably higher than in other areas of the country. The simulations showed that deposition from the worst-case scenario of a hypothetical K-27 accident would be at least two orders of magnitude lower than the deposition observed in Norway following the Chernobyl accident. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Comparative genomic analysis of clinical and environmental Vibrio vulnificus isolates revealed biotype 3 evolutionary relationships.

PubMed

Koton, Yael; Gordon, Michal; Chalifa-Caspi, Vered; Bisharat, Naiel

2014-01-01

In 1996 a common-source outbreak of severe soft tissue and bloodstream infections erupted among Israeli fish farmers and fish consumers due to changes in fish marketing policies. The causative pathogen was a new strain of Vibrio vulnificus, named biotype 3, which displayed a unique biochemical and genotypic profile. Initial observations suggested that the pathogen erupted as a result of genetic recombination between two distinct populations. We applied a whole genome shotgun sequencing approach using several V. vulnificus strains from Israel in order to study the pan genome of V. vulnificus and determine the phylogenetic relationship of biotype 3 with existing populations. The core genome of V. vulnificus based on 16 draft and complete genomes consisted of 3068 genes, representing between 59 and 78% of the whole genome of 16 strains. The accessory genome varied in size from 781 to 2044 kbp. Phylogenetic analysis based on whole, core, and accessory genomes displayed similar clustering patterns with two main clusters, clinical (C) and environmental (E), all biotype 3 strains formed a distinct group within the E cluster. Annotation of accessory genomic regions found in biotype 3 strains and absent from the core genome yielded 1732 genes, of which the vast majority encoded hypothetical proteins, phage-related proteins, and mobile element proteins. A total of 1916 proteins (including 713 hypothetical proteins) were present in all human pathogenic strains (both biotype 3 and non-biotype 3) and absent from the environmental strains. Clustering analysis of the non-hypothetical proteins revealed 148 protein clusters shared by all human pathogenic strains; these included transcriptional regulators, arylsulfatases, methyl-accepting chemotaxis proteins, acetyltransferases, GGDEF family proteins, transposases, type IV secretory system (T4SS) proteins, and integrases. Our study showed that V. vulnificus biotype 3 evolved from environmental populations and formed a genetically distinct group within the E-cluster. The unique epidemiological circumstances facilitated disease outbreak and brought this genotype to the attention of the scientific community.

Aryl-O reductive elimination from reaction of well-defined aryl-Cu(III) species with phenolates: the importance of ligand reactivity.

PubMed

Casitas, Alicia; Ioannidis, Nikolaos; Mitrikas, George; Costas, Miquel; Ribas, Xavi

2011-09-21

Well-defined aryl-Cu(III) species undergo rapid reductive elimination upon reaction with phenolates (PhO(-)), to form aryl-OPh cross-coupling products. Kinetic studies show that the reaction follows a different mechanistic pathway compared to the reaction with phenols. The pH active cyclized pincer-like ligand undergoes an initial amine deprotonation that triggers a faster reactivity at room temperature. A mechanistic proposal for the enhanced reactivity and the role of EPR-detected Cu(II) species will be discussed in detail. This journal is © The Royal Society of Chemistry 2011

Engaging Students in Analyzing and Interpreting Data to Construct Mathematical Models: An Analysis of Students' Reasoning in a Method of Initial Rates Task

ERIC Educational Resources Information Center

Becker, Nicole M.; Rupp, Charlie A.; Brandriet, Alexandra

2017-01-01

Models related to the topic of chemical kinetics are critical for predicting and explaining chemical reactivity. Here we present a qualitative study of 15 general chemistry students' reasoning about a method of initial rates task. We asked students to discuss their understanding of the terms rate law and initial rate, and then analyze rate and…

High-Energy-Density LCA-Coupled Structural Energetic Materials for Counter WMD Applications

DTIC Science & Technology

2014-04-01

reactive ( thermite ) fillers as high-energy-density structural energetic materials. The specific objectives include performing fundamental studies to...a) investigate mechanics of dynamic densification and reaction initiation in Ta+Fe2O3 and Ta+Bi2O3 thermite powder mixtures and to (b) design and...initiation in the thermite filler and allow controlled fragmentation. Linear Cellular A; counter WMDs; shock-compression and impact-initiated reactions

Prediction error and trace dominance determine the fate of fear memories after post-training manipulations

PubMed Central

Alfei, Joaquín M.; Ferrer Monti, Roque I.; Molina, Victor A.; Bueno, Adrián M.

2015-01-01

Different mnemonic outcomes have been observed when associative memories are reactivated by CS exposure and followed by amnestics. These outcomes include mere retrieval, destabilization–reconsolidation, a transitional period (which is insensitive to amnestics), and extinction learning. However, little is known about the interaction between initial learning conditions and these outcomes during a reinforced or nonreinforced reactivation. Here we systematically combined temporally specific memories with different reactivation parameters to observe whether these four outcomes are determined by the conditions established during training. First, we validated two training regimens with different temporal expectations about US arrival. Then, using Midazolam (MDZ) as an amnestic agent, fear memories in both learning conditions were submitted to retraining either under identical or different parameters to the original training. Destabilization (i.e., susceptibly to MDZ) occurred when reactivation was reinforced, provided the occurrence of a temporal prediction error about US arrival. In subsequent experiments, both treatments were systematically reactivated by nonreinforced context exposure of different lengths, which allowed to explore the interaction between training and reactivation lengths. These results suggest that temporal prediction error and trace dominance determine the extent to which reactivation produces the different outcomes. PMID:26179232

Quantum Dynamics Study of the Isotopic Effect on Capture Reactions: HD, D2 + CH3

NASA Technical Reports Server (NTRS)

Wang, Dunyou; Kwak, Dochan (Technical Monitor)

2002-01-01

Time-dependent wave-packet-propagation calculations are reported for the isotopic reactions, HD + CH3 and D2 + CH3, in six degrees of freedom and for zero total angular momentum. Initial state selected reaction probabilities for different initial rotational-vibrational states are presented in this study. This study shows that excitations of the HD(D2) enhances the reactivities; whereas the excitations of the CH3 umbrella mode have the opposite effects. This is consistent with the reaction of H2 + CH3. The comparison of these three isotopic reactions also shows the isotopic effects in the initial-state-selected reaction probabilities. The cumulative reaction probabilities (CRP) are obtained by summing over initial-state-selected reaction probabilities. The energy-shift approximation to account for the contribution of degrees of freedom missing in the six dimensionality calculation is employed to obtain approximate full-dimensional CRPs. The rate constant comparison shows H2 + CH3 reaction has the biggest reactivity, then HD + CH3, and D2 + CH3 has the smallest.

Dietary phytochemicals and cancer prevention: Nrf2 signaling, epigenetics, and cell death mechanisms in blocking cancer initiation and progression.

PubMed

Lee, Jong Hun; Khor, Tin Oo; Shu, Limin; Su, Zheng-Yuan; Fuentes, Francisco; Kong, Ah-Ng Tony

2013-02-01

Reactive metabolites from carcinogens and oxidative stress can drive genetic mutations, genomic instability, neoplastic transformation, and ultimately carcinogenesis. Numerous dietary phytochemicals in vegetables/fruits have been shown to possess cancer chemopreventive effects in both preclinical animal models and human epidemiological studies. These phytochemicals could prevent the initiation of carcinogenesis via either direct scavenging of reactive oxygen species/reactive nitrogen species (ROS/RNS) or, more importantly, the induction of cellular defense detoxifying/antioxidant enzymes. These defense enzymes mediated by Nrf2-antioxidative stress and anti-inflammatory signaling pathways can contribute to cellular protection against ROS/RNS and reactive metabolites of carcinogens. In addition, these compounds would kill initiated/transformed cancer cells in vitro and in in vivo xenografts via diverse anti-cancer mechanisms. These mechanisms include the activation of signaling kinases (e.g., JNK), caspases and the mitochondria damage/cytochrome c pathways. Phytochemicals may also have anti-cancer effects by inhibiting the IKK/NF-κB pathway, inhibiting STAT3, and causing cell cycle arrest. In addition, other mechanisms may include epigenetic alterations (e.g., inhibition of HDACs, miRNAs, and the modification of the CpG methylation of cancer-related genes). In this review, we will discuss: the current advances in the study of Nrf2 signaling; Nrf2-deficient tumor mouse models; the epigenetic control of Nrf2 in tumorigenesis and chemoprevention; Nrf2-mediated cancer chemoprevention by naturally occurring dietary phytochemicals; and the mutation or hyper-expression of the Nrf2-Keap1 signaling pathway in advanced tumor cells. The future development of dietary phytochemicals for chemoprevention must integrate in vitro signaling mechanisms, relevant biomarkers of human diseases, and combinations of different phytochemicals and/or non-toxic therapeutic drugs, including NSAIDs. Copyright © 2012 Elsevier Inc. All rights reserved.

Meso-Scale Experimental & Numerical Studies for Predicting Macro-scale Performance of Advanced Reactive Materials (ARMs)

DTIC Science & Technology

2015-04-01

of impact-initiated reactions in Ti-Al-B based reactive materials in the form of compacts of powders of different sizes and morphologies . The major...More specifically, the influence of material-inherent elastic/plastic properties and reactant configuration (e.g., porosity, morphology , spacing...materials in the form of compacts of powders of different sizes and morphologies . The major goal is to delineate how processes of localized deformation and

Quantitative Microbial Risk Assessment of Freshwater Impacted by Animal Fecal Material

EPA Science Inventory

We evaluated the potential for human illness from a hypothetical recreational exposure to freshwater impacted by land-applied, agricultural animal fecal material. The hypothetical exposure scenario included the following characteristics: 1) fresh cattle manure, pig slurry, or ch...

The impact of arbitrarily applicable relational responding on evaluative learning about hypothetical money and shock outcomes.

PubMed

Dymond, Simon; Molet, Mikael; Davies, Lynette

2017-08-01

Evaluative learning comprises changes in preferences after co-occurrences between conditioned stimuli (CSs) and an unconditioned stimulus (US) of affective value. Co-occurrences may involve relational responding. Two experiments examined the impact of arbitrary relational responding on evaluative preferences for hypothetical money and shock outcomes. In Experiment 1, participants were trained to make arbitrary relational responses by placing CSs of the same size but different colours into boxes and were then instructed that these CSs represented different intensities of hypothetical USs (money or shock). Liking ratings of the CSs were altered in accordance with the underlying bigger/smaller than relations. A reversal of preference was also observed: the CS associated with the smallest hypothetical shock was rated more positively than the CS associated with the smallest amount of hypothetical money. In Experiment 2, procedures from Relational Frame Theory (RFT) established a relational network of more than/less than relations consisting of five CSs (A-B-C-D-E). Overall, evaluative preferences were altered, but not reversed, depending on (a) how stimuli had been related to one another during the learning phase and (b) whether those stimuli referred to money or shocks. The contribution of RFT to evaluative learning research is discussed.

Suit the action to the word, the word to the action: Hypothetical choices and real decisions in Medicare Part D

PubMed Central

Kesternich, Iris; Heiss, Florian; McFadden, Daniel; Winter, Joachim

2016-01-01

In recent years, consumer choice has become an important element of public policy. One reason is that consumers differ in their tastes and needs, which they can express most easily through their own choices. Elements that strengthen consumer choice feature prominently in the design of public insurance markets, for instance in the United States in the recent introduction of prescription drug coverage for older individuals via Medicare Part D. For policy makers who design such a market, an important practical question in the design phase of such a new program is how to deduce enrollment and plan selection preferences prior to its introduction. In this paper, we investigate whether hypothetical choice experiments can serve as a tool in this process. We combine data from hypothetical and real plan choices, elicited around the time of the introduction of Medicare Part D. We first analyze how well the hypothetical choice data predict willingness to pay and market shares at the aggregate level. We then analyze predictions at the individual level, in particular how insurance demand varies with observable characteristics. We also explore whether the extent of adverse selection can be predicted using hypothetical choice data alone. PMID:23317633

Expression of the Eukaryotic Translation Initiation Factors 4E and 2α in Non-Hodgkin’s Lymphomas

PubMed Central

Wang, Songtao; Rosenwald, Igor B.; Hutzler, Michael J.; Pihan, German A.; Savas, Lou; Chen, Jane-Jane; Woda, Bruce A.

1999-01-01

Transition of cells from quiescence to proliferation requires an increase in the rate of protein synthesis, which is regulated in part by two key translation initiation factors, 4E and 2α. The expression and activity of both factors are increased transiently when normal resting cells are stimulated to proliferate. They are constitutively elevated in oncogene transformed cultured cells, and overexpression of either initiation factor in rodent cells makes them tumorigenic. In this study we investigate an association between the expression of translation initiation factors and lymphomagenesis. We have analyzed the expression of the protein synthesis initiation factors 4E and 2α by immunohistochemistry in reactive lymph nodes and several types of non-Hodgkin’s lymphoma representing a wide range of clinical behaviors based on the Revised European-American Lymphoma behavioral classification. The study included 7 benign lymph nodes with follicular hyperplasia, 26 indolent lymphomas (6 marginal zone lymphomas, 7 small lymphocytic lymphomas, and 13 follicular lymphomas, grades 1 and 2), 16 moderately aggressive lymphomas (8 mantle cell lymphomas and 8 follicular lymphomas, grade 3), 24 aggressive lymphomas (14 large-B-cell lymphomas and 10 anaplastic large-cell lymphomas), and 15 highly aggressive lymphomas (7 lymphoblastic lymphomas and 8 Burkitt’s lymphomas). Strong expression of initiation factors 4E and 2α was demonstrated in the germinal centers of reactive follicles. Minimal or no expression was seen in the mantle zones and surrounding paracortices, indicating that high expression of initiation factors 4E and 2α is associated with the active proliferation of lymphocytes. Most cases of aggressive and highly aggressive lymphomas showed strong expression of initiation factors 4E and 2α, in contrast to the cases of indolent and moderately aggressive lymphoma, in which their expression was intermediate between the germinal centers and the mantles of reactive follicles. A positive correlation was found between the expression of both initiation factors 4E and 2α and the Revised European-American Lymphoma behavior classification (P < 0.05). Thus, constitutively increased expression of initiation factors 4E and 2α may play an important role in the development of lymphomas and is correlated with their biological aggressiveness. PMID:10393856

Symbolic play and language development.

PubMed

Orr, Edna; Geva, Ronny

2015-02-01

Symbolic play and language are known to be highly interrelated, but the developmental process involved in this relationship is not clear. Three hypothetical paths were postulated to explore how play and language drive each other: (1) direct paths, whereby initiation of basic forms in symbolic action or babbling, will be directly related to all later emerging language and motor outputs; (2) an indirect interactive path, whereby basic forms in symbolic action will be associated with more complex forms in symbolic play, as well as with babbling, and babbling mediates the relationship between symbolic play and speech; and (3) a dual path, whereby basic forms in symbolic play will be associated with basic forms of language, and complex forms of symbolic play will be associated with complex forms of language. We micro-coded 288 symbolic vignettes gathered during a yearlong prospective bi-weekly examination (N=14; from 6 to 18 months of age). Results showed that the age of initiation of single-object symbolic play correlates strongly with the age of initiation of later-emerging symbolic and vocal outputs; its frequency at initiation is correlated with frequency at initiation of babbling, later-emerging speech, and multi-object play in initiation. Results support the notion that a single-object play relates to the development of other symbolic forms via a direct relationship and an indirect relationship, rather than a dual-path hypothesis. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

The costs of crime during and after publicly-funded treatment for opioid use disorders: a population-level study for the state of California

PubMed Central

Krebs, Emanuel; Urada, Darren; Evans, Elizabeth; Huang, David; Hser, Yih-Ing; Nosyk, Bohdan

2016-01-01

Background and aims Treatment for opioid use disorders (OUD) reduces the risk of mortality and infectious disease transmission; however, opportunities to quantify the potential economic benefits of associated decreases in drug-related crime are scarce. This paper aimed to estimate the costs of crime during and after periods of engagement in publicly-funded treatment for OUD to compare total costs of crime over a hypothetical 6-month period following initiation of opioid agonist treatment (OAT) versus detoxification. Design Retrospective, administrative data-based cohort study with comprehensive information on drug treatment and criminal justice systems interactions. Setting Publicly-funded drug treatment facilities in California, USA (2006–2010). Participants 31,659 individuals admitted for the first time to treatment for OUD, and who were linked with criminal justice and mortality data, were followed during a median 2.3 years. Median age at first treatment admission was 32, 35.8% were women, and 37.1% primarily used prescription opioids. Measurements Daily costs of crime (2014$US) were calculated from a societal perspective and were composed of the costs of policing, court, corrections, and criminal victimization. We estimated the average marginal effect of treatment engagement in OAT or detoxification adjusting for potential fixed and time-varying confounders, including drug use and criminal justice system involvement prior to treatment initiation. Findings Daily costs of crime during treatment compared with after treatment were $126 lower for OAT (95% CI: $116, $136) and $144 lower for detoxification ($135, $154). Summing the costs of crime during and after treatment over a hypothetical 6-month period using the observed median durations of OAT (161 days) and detoxification (19 days), we estimated that enrolling an individual in OAT as opposed to detoxification would save $17,550 ($16,840, $18,383). Conclusions In publicly-funded drug treatment facilities in California USA, engagement in treatment for opioid use disorders is associated with lower costs of crime in the six months following initiation of treatment, and the economic benefits were far greater for individuals receiving time-unlimited treatment. PMID:27981691

The costs of crime during and after publicly funded treatment for opioid use disorders: a population-level study for the state of California.

PubMed

Krebs, Emanuel; Urada, Darren; Evans, Elizabeth; Huang, David; Hser, Yih-Ing; Nosyk, Bohdan

2017-05-01

Treatment for opioid use disorders (OUD) reduces the risk of mortality and infectious disease transmission; however, opportunities to quantify the potential economic benefits of associated decreases in drug-related crime are scarce. This paper aimed to estimate the costs of crime during and after periods of engagement in publicly funded treatment for OUD to compare total costs of crime during a hypothetical 6-month period following initiation of opioid agonist treatment (OAT) versus detoxification. Retrospective, administrative data-based cohort study with comprehensive information on drug treatment and criminal justice systems interactions. Publicly funded drug treatment facilities in California, USA (2006-10). A total of 31 659 individuals admitted for the first time to treatment for OUD, and who were linked with criminal justice and mortality data, were followed during a median 2.3 years. Median age at first treatment admission was 32, 35.8% were women and 37.1% primarily used prescription opioids. Daily costs of crime (US$2014) were calculated from a societal perspective and were composed of the costs of policing, court, corrections and criminal victimization. We estimated the average marginal effect of treatment engagement in OAT or detoxification adjusting for potential fixed and time-varying confounders, including drug use and criminal justice system involvement prior to treatment initiation. Daily costs of crime during treatment compared with after treatment were $126 lower for OAT [95% confidence interval (CI) = $116, $136] and $144 lower for detoxification (95% CI = $135, $154). Summing the costs of crime during and after treatment over a hypothetical 6-month period using the observed median durations of OAT (161 days) and detoxification (19 days), we estimated that enrolling an individual in OAT as opposed to detoxification would save $17 550 ($16 840, $18 383). In publicly funded drug treatment facilities in California, USA, engagement in treatment for opioid use disorders is associated with lower costs of crime in the 6 months following initiation of treatment, and the economic benefits were far greater for individuals receiving time-unlimited treatment. © 2016 Society for the Study of Addiction.

How different terminology for ductal carcinoma in situ impacts women's concern and treatment preferences: a randomised comparison within a national community survey.

PubMed

McCaffery, Kirsten; Nickel, Brooke; Moynihan, Ray; Hersch, Jolyn; Teixeira-Pinto, Armando; Irwig, Les; Barratt, Alexandra

2015-11-02

There have been calls to remove 'carcinoma' from terminology for in situ cancers such as ductal carcinoma in situ (DCIS), to reduce overdiagnosis and overtreatment. We investigated the effect of describing DCIS as 'abnormal cells' versus 'pre-invasive breast cancer cells' on women's concern and treatment preferences. Community sample of Australian women (n=269) who spoke English as their main language at home. Randomised comparison within a community survey. Women considered a hypothetical scenario involving a diagnosis of DCIS described as either 'abnormal cells' (arm A) or 'pre-invasive breast cancer cells' (arm B). Within each arm, the initial description was followed by the alternative term and outcomes reassessed. Women in both arms indicated high concern, but still indicated strong initial preferences for watchful waiting (64%). There were no differences in initial concern or preferences by trial arm. However, more women in arm A ('abnormal cells' first term) indicated they would feel more concerned if given the alternative term ('pre-invasive breast cancer cells') compared to women in arm B who received the terms in the opposite order (67% arm A vs 52% arm B would feel more concerned, p=0.001). More women in arm A also changed their preference towards treatment when the terminology was switched from 'abnormal cells' to 'pre-invasive breast cancer cells' compared to arm B. In arm A, 18% of women changed their preference to treatment while only 6% changed to watchful waiting (p=0.008). In contrast, there were no significant changes in treatment preference in arm B when the terminology was switched (9% vs 8% changed their stated preference). In a hypothetical scenario, interest in watchful waiting for DCIS was high, and changing terminology impacted women's concern and treatment preferences. Removal of the cancer term from DCIS may assist in efforts towards reducing overtreatment. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Molecular dynamics simulation of sodium aluminosilicate glass structures and glass surface-water reactions using the reactive force field (ReaxFF)

NASA Astrophysics Data System (ADS)

Dongol, R.; Wang, L.; Cormack, A. N.; Sundaram, S. K.

2018-05-01

Reactive potentials are increasingly used to study the properties of glasses and glass water reactions in a reactive molecular dynamics (MD) framework. In this study, we have simulated a ternary sodium aluminosilicate glass and investigated the initial stages of the glass surface-water reactions at 300 K using reactive force field (ReaxFF). On comparison of the simulated glass structures generated using ReaxFF and classical Buckingham potentials, our results show that the atomic density profiles calculated for the surface glass structures indicate a bond-angle distribution dependency. The atomic density profiles also show higher concentrations of non-bridging oxygens (NBOs) and sodium ions at the glass surface. Additionally, we present our results of formation of silanol species and the diffusion of water molecules at the glass surface using ReaxFF.

Ozonation of the pharmaceutical compound ranitidine: reactivity and kinetic aspects.

PubMed

Rivas, Javier; Gimeno, Olga; Encinas, Angel; Beltrán, Fernando

2009-07-01

Ranitidine has been ozonated under different operating conditions of pH, applied ozone dose, initial ranitidine concentration and presence or absence of free radical inhibitors. Results of ranitidine evolution with time indicate a high reactivity of this compound with molecular ozone. Mineralization levels achieved in the order of 20-25% suggest that the (CH3)2-N-CH2- moiety bonded to the furan ring could be separated from the rest of the ranitidine structure and further mineralized. Only alkaline conditions (pH=11) are capable of increasing TOC conversion up to values close to 70%. Determination of the direct ozonation rate constant for ranitidine by means of competitive kinetics reveals an unacceptable dependence of the aforementioned constant with the reference compound reactivity. It is hypothesised that only reference compounds with reactivity similar to the target species should be used.

Impact of microstructure evolution on the difference between geometric and reactive surface areas in natural chalk

NASA Astrophysics Data System (ADS)

Yang, Y.; Bruns, S.; Stipp, S. L. S.; Sørensen, H. O.

2018-05-01

The coupling between flow and mineral dissolution drives the evolution of many natural and engineered flow systems. Pore surface changes as microstructure evolves but this transient behaviour has traditionally been difficult to model. We combined a reactor network model with experimental, greyscale tomography data to establish the morphological grounds for differences among geometric, reactive and apparent surface areas in dissolving chalk. This approach allowed us to study the effects of initial geometry and macroscopic flow rate independently. The simulations showed that geometric surface, which represents a form of local transport heterogeneity, increases in an imposed flow field, even when the porous structure is chemically homogeneous. Hence, the fluid-reaction coupling leads to solid channelisation, which further results in fluid focusing and an increase in geometric surface area. Fluid focusing decreases the area of reactive surface and the residence time of reactant, both contribute to the over-normalisation of reaction rate. In addition, the growing and merging of microchannels, near the fluid entrance, contribute to the macroscopic, fast initial dissolution rate of rocks.

The basic reproduction number R0 and effectiveness of reactive interventions during dengue epidemics: the 2002 dengue outbreak in Easter Island, Chile.

PubMed

Chowell, Gerardo; Fuentes, R; Olea, A; Aguilera, X; Nesse, H; Hyman, J M

2013-01-01

We use a stochastic simulation model to explore the effect of reactive intervention strategies during the 2002 dengue outbreak in the small population of Easter Island, Chile. We quantified the effect of interventions on the transmission dynamics and epidemic size as a function of the simulated control intensity levels and the timing of initiation of control interventions. Because no dengue outbreaks had been reported prior to 2002 in Easter Island, the 2002 epidemic provided a unique opportunity to estimate the basic reproduction number R0 during the initial epidemic phase, prior to the start of control interventions. We estimated R0 at 27.2 (95%CI: 14.8, 49.3). We found that the final epidemic size is highly sensitive to the timing of start of interventions. However, even when the control interventions start several weeks after the epidemic onset, reactive intervention efforts can have a significant impact on the final epidemic size. Our results indicate that the rapid implementation of control interventions can have a significant effect in reducing the epidemic size of dengue epidemics.

Mitochondrial membrane permeabilization and cell death during myocardial infarction: roles of calcium and reactive oxygen species

PubMed Central

Webster, Keith A

2013-01-01

Excess generation of reactive oxygen species (ROS) and cytosolic calcium accumulation play major roles in the initiation of programmed cell death during acute myocardial infarction. Cell death may include necrosis, apoptosis and autophagy, and combinations thereof. During ischemia, calcium handling between the sarcoplasmic reticulum and myofilament is disrupted and calcium is diverted to the mitochondria causing swelling. Reperfusion, while essential for survival, reactivates energy transduction and contractility and causes the release of ROS and additional ionic imbalance. During acute ischemia–reperfusion, the principal death pathways are programmed necrosis and apoptosis through the intrinsic pathway, initiated by the opening of the mitochondrial permeability transition pore and outer mitochondrial membrane permeabilization, respectively. Despite intense investigation, the mechanisms of action and modes of regulation of mitochondrial membrane permeabilization are incompletely understood. Extrinsic apoptosis, necroptosis and autophagy may also contribute to ischemia–reperfusion injury. In this review, the roles of dysregulated calcium and ROS and the contributions of Bcl-2 proteins, as well as mitochondrial morphology in promoting mitochondrial membrane permeability change and the ensuing cell death during myocardial infarction are discussed. PMID:23176689

Reactivity of syringyl and guaiacyl lignin units and delignification kinetics in the kraft pulping of Eucalyptus globulus wood using Py-GC-MS/FID.

PubMed

Lourenço, Ana; Gominho, Jorge; Marques, António Velez; Pereira, Helena

2012-11-01

Eucalyptus globulus sapwood and heartwood showed no differences in lignin content (23.0% vs. 23.7%) and composition: syringyl-lignin (17.9% vs. 18.0%) and guaiacyl-lignin (4.8% vs. 5.2%). Delignification kinetics of S- and G-units in heartwood and sapwood was investigated by Py-GC-MS/FID at 130, 150 and 170°C and modeled as double first-order reactions. Reactivity differences between S and G-units were small during the main pulping phase and the higher reactivity of S over G units was better expressed in the later pulping stage. The residual lignin composition in pulps was different from wood or from samples in the initial delignification stages, with more G and H-units. S/G ratio ranged from 3 to 4.5 when pulp residual lignin was higher than 10%, decreasing rapidly to less than 1. The S/H was initially around 20 (until 15% residual lignin), decreasing to 4 when residual lignin was about 3%. Copyright © 2012 Elsevier Ltd. All rights reserved.

Techno-economical optimization of Reactive Blue 19 removal by combined electrocoagulation/coagulation process through MOPSO using RSM and ANFIS models.

PubMed

Taheri, M; Alavi Moghaddam, M R; Arami, M

2013-10-15

In this research, Response Surface Methodology (RSM) and Adaptive Neuro Fuzzy Inference System (ANFIS) models were applied for optimization of Reactive Blue 19 removal using combined electrocoagulation/coagulation process through Multi-Objective Particle Swarm Optimization (MOPSO). By applying RSM, the effects of five independent parameters including applied current, reaction time, initial dye concentration, initial pH and dosage of Poly Aluminum Chloride were studied. According to the RSM results, all the independent parameters are equally important in dye removal efficiency. In addition, ANFIS was applied for dye removal efficiency and operating costs modeling. High R(2) values (≥85%) indicate that the predictions of RSM and ANFIS models are acceptable for both responses. ANFIS was also used in MOPSO for finding the best techno-economical Reactive Blue 19 elimination conditions according to RSM design. Through MOPSO and the selected ANFIS model, Minimum and maximum values of 58.27% and 99.67% dye removal efficiencies were obtained, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

Reactivity of coal in direct hydrogenation processes: Technical progress report, March-May 1987

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

Baldwin, R.M.; Miller, R.L.

Research during the past quarter centered on continuation of two facets related to the study of coal reactivity in direct hydrogenation liquefaction processes. Five coals from the Argonne Premium coal collection were liquefied at three temperature levels in order to gather data for kinetic analysis purposes. Conversion of these coals to THF-, toluene-, and hexane-solubles was determined at temperatures of 425, 400, and 375 C, and nominal reaction times of 3, 5, 10, 15, and 40 minutes in the microautoclave batch reaction system. Preliminary mathematical modeling of the data using simple irreversible rate expressions and more complex formulations based onmore » a statistical distribution of activation energies was initiated in order to investigate the feasibility of utilizing activation energy as an additional reactivity screening factor. Use of complex models such as the Anthony-Howard formulation for purposes of activation energy determination from liquefaction data at one temperature level was further examined. Five of the 21 coals from the Penn State Premium coal sample bank were liquefied at the standard reactivity screening conditions, and the rate and extent of conversion to THF-, and toluene-, and hexane-solubles quantified. These data were added to the existing data base containing similar information for the prior coal suites from the Exxon and Argonne collections, and preliminary correlational efforts for reactivity vs. coal properties were initiated. Prior conclusions regarding the effect of rank on the rate and extent of conversion were qualitatively verified from the data collected. 1 ref., 13 figs., 2 tabs.« less

Study on CO2 gasification reactivity and physical characteristics of biomass, petroleum coke and coal chars.

PubMed

Huo, Wei; Zhou, Zhijie; Chen, Xueli; Dai, Zhenghua; Yu, Guangsuo

2014-05-01

Gasification reactivities of six different carbonaceous material chars with CO2 were determined by a Thermogravimetric Analyzer (TGA). Gasification reactivities of biomass chars are higher than those of coke and coal chars. In addition, physical structures and chemical components of these chars were systematically tested. It is found that the crystalline structure is an important factor to evaluate gasification reactivities of different chars and the crystalline structures of biomass chars are less order than those of coke and coal chars. Moreover, initial gasification rates of these chars were measured at high temperatures and with relatively large particle sizes. The method of calculating the effectiveness factor η was used to quantify the effect of pore diffusion on gasification. The results show that differences in pore diffusion effects among gasification with various chars are prominent and can be attributed to different intrinsic gasification reactivities and physical characteristics of different chars. Copyright © 2014 Elsevier Ltd. All rights reserved.

Links between physical fitness and cardiovascular reactivity and recovery to psychological stressors: A meta-analysis.

PubMed

Forcier, Kathleen; Stroud, Laura R; Papandonatos, George D; Hitsman, Brian; Reiches, Meredith; Krishnamoorthy, Jenelle; Niaura, Raymond

2006-11-01

A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity. Copyright 2006 APA, all rights reserved.

Substrate reactivity as a function of the extent of reaction in the enzymatic hydrolysis of lignocellulose

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

Desai, S.G.; Converse, A.O.

1997-12-20

In an effort to better understand the role of the substrate in the rapid fall off in the rate of enzymatic hydrolysis of cellulose with conversion, substrate reactivity was measured as a function of conversion. These measurements were made by interrupting the hydrolysis of pretreated wood at various degrees of conversion; and, after boiling and washing, restarting the hydrolysis in fresh butter with fresh enzyme. The comparison of the restart rate per enzyme adsorbed with the initial rate per enzyme adsorbed, both extrapolated back to zero conversion, provides a measurement of the substrate reactivity without the complications of product inhibitionmore » or cellulase inactivation. The results indicate that the substrate reactivity falls only modestly as conversion increases. However, the restart rate is still higher than the rate of the uninterrupted hydrolysis, particularly at high conversion. Hence the authors conclude that the loss of substrate reactivity is not the principal cause for the long residence time required for complete conversion.« less

Ecofriendly degradation of sulfonated diazo dye C.I. Reactive Green 19A using Micrococcus glutamicus NCIM-2168.

PubMed

Saratale, R G; Saratale, G D; Chang, J S; Govindwar, S P

2009-09-01

Micrococcus glutamicus NCIM-2168 exhibited complete decolorization and degradation of C.I. Reactive Green 19A (an initial concentration of 50 mg l(-1)) within 42 h at temperature 37 degrees C and pH 8, under static condition. Extent of mineralization was determined with total organic carbon (TOC) and chemical oxygen demand (COD) measurement, showing a satisfactory reduction of TOC (72%) and COD (66%) within 42 h. Enzyme studies shows involvement of oxidoreductive enzymes in decolorization/degradation process. Analytical studies of the extracted metabolites confirmed the significant degradation of Reactive Green 19A into various metabolites. The microbial toxicity and phytotoxicity assay revealed that the degradation of Reactive Green 19A produced nontoxic metabolites. In addition, the M. glutamicus strain was applied to decolorize a mixture of ten reactive dyes showing a 63% decolorization (in terms of decrease in ADMI value) within 72 h, along with 48% and 42% reduction in TOC and COD under static condition.

Extensive CD4 and CD8 T-cell cross-reactivity between alphaherpesviruses1

PubMed Central

Dong, Lichun; Russell, Ronnie M.; Barlow, Russell S.; Haas, Juergen G.; Ramchandani, Meena S.; Johnston, Christine; Buus, Soren; Redwood, Alec J.; White, Katie D.; Mallal, Simon A.; Phillips, Elizabeth J.; Posavad, Christine M.; Wald, Anna; Koelle, David M.

2015-01-01

The alphaherpesvirinae subfamily includes HSV types 1 and 2 and the sequence-divergent pathogen varicella zoster virus (VZV). T cells, controlled by TCR and HLA molecules that tolerate limited epitope amino acid variation, might cross-react between these microbes. We show that memory PBMC expansion with either HSV or VZV enriches for CD4 T cell lines that recognize the other agent at the whole virus, protein, and peptide levels, consistent with bi-directional cross-reactivity. HSV-specific CD4 T cells recovered from HSV seronegative persons can be partially explained by such VZV cross-reactivity. HSV-1-reactive CD8 T cells also cross-react with VZV-infected cells, full-length VZV proteins, and VZV peptides, and kill VZV-infected dermal fibroblasts. Mono- and cross-reactive CD8 T cells use distinct TCRB CDR3 sequences. Cross-reactivity to VZV is reconstituted by cloning and expressing TCRA/TCRB receptors from T-cells that are initially isolated using HSV reagents. Overall, we define 13 novel CD4 and CD8 HSV-VZV cross-reactive epitopes and strongly imply additional cross-reactive peptide sets. Viral proteins can harbor both CD4 and CD8 HSV/VZV cross-reactive epitopes. Quantitative estimates of HSV/VZV cross-reactivity for both CD4 and CD8 T cells vary from 10-50%. Based on these findings, we hypothesize host herpesvirus immune history may influence the pathogenesis and clinical outcome of subsequent infections or vaccinations for related pathogens, and that cross-reactive epitopes and TCRs may be useful for multi-alphaherpesvirus vaccine design and adoptive cellular therapy. PMID:26810224

Parenting style and adolescent's reaction to conflict: is there a relationship?

PubMed

Miller, Jessica M; DiIorio, Colleen; Dudley, William

2002-12-01

To determine if the reactions of adolescents toward hypothetical situations that can lead to conflict and violence varied by parenting style of their mothers. This study was part of a larger research project involving adolescents and their mothers participating in a longitudinal HIV-prevention program. Mothers and their adolescents were recruited from a community-based organization (CBO) and interviewed separately. Data were analyzed using the responses of 439 African-American adolescents ranging from ages 11 to 14 years. The responses of adolescents to questions about parenting were used to classify mothers into one of three parenting styles: authoritative, authoritarian, or permissive. The "anticipated reactions to hypothetical situations" scale consists of 11 items with 6 response categories. The six responses were reclassified into three categories ranging from "not at all violent" to "extremely violent." Higher scores indicate more violent reactions to the hypothetical situations. The parenting scale consists of two subscales: a 13-item parental involvement scale and a 13-item parental control scale. Items were rated on a 5-point Likert scale from "strongly disagree" to "strongly agree." Analysis of variance was used to determine if the anticipated reactions of adolescents toward hypothetical situations varied by parenting style of their mothers. Adolescent participants who reported a more permissive parenting style expressed more intense negative reactions toward the hypothetical situations that can provoke conflict. Male adolescents also expressed more intense reactions than females to the situations. There was no difference in intensity of reaction by age after controlling for gender and parenting style. Parenting style is associated with adolescents' reactions to hypothetical situations that can provoke conflict. This finding highlights the importance of considering parents and their approach to child-rearing as a factor in the adolescent's ability to react to conflict.

Fetal acoustic stimulation test for early intrapartum fetal monitoring.

PubMed

Goonewardene, M; Hanwellage, K

2011-03-01

The fetal acoustic stimulation test (FAST) is a simple cost effective screening test for antenatal fetal monitoring. The aim of the study was to evaluate the FAST as a screening test for early intrapartum fetal well being. An initial non stress test (NST) followed by a FAST using corometric model 146 was carried out in 486 participants in early labour with uncomplicated singleton pregnancies and > 32 weeks gestation. A repeat NST was recorded in the participants who had an initial non reactive NST. The results of the NST and FAST were compared with fetal outcome. Maternal perception of fetal movements after FAST, results of NST before and after FAST, and the babies' 5 minute APGAR scores were measured. Of the 486 participants 413 (85%) noticed fetal movements after FAST. Initial NST was non reactive in 203 (42%) but 149 (31%) became reactive after FAST. Compared to the NST, FAST had a better sensitivity (97% vs 62%, p < 0.001), specificity (100% vs 87%, p = 0.017), positive predictive value (100% vs 98%, p = 0.024), negative predictive value (79% vs 17%, p < 0.001) and accuracy (99%vs 64%, p < 0.001) in predicting 5 minute APGAR < 7 in the baby. FAST is a reliable screening test for assessing fetal well being in early labour. It complements the NST and is better than the NST alone.

Investigation of ambient OH reactivity at a receptor site impacted by industrial, urban and marine emissions: Identification of missing OH reactivity

NASA Astrophysics Data System (ADS)

Dusanter, Sébastien; Michoud, Vincent; Léonardis, Thierry; Locoge, Nadine; Riffault, Véronique; Zhang, Shouwen

2015-04-01

The hydroxyl radical (OH), the main daytime oxidant in the troposphere, plays a key role in atmospheric chemistry. OH initiates the oxidation of most of the trace gases, including Volatile Organic Compounds (VOC), leading to the formation of harmful secondary pollutants such as ozone and secondary organic aerosols. VOCs are directly emitted by a large number of natural and anthropogenic sources and can be formed photochemically. It is expected that several thousand VOCs could be present in the troposphere at ppt-ppb levels (Goldstein and Galbally, ES&T, 2007), making exhaustive measurements of VOCs currently unfeasible with common analytical techniques. In this context, measuring the total sink of OH, so called total OH reactivity, can provide insights into the reactivity of unmeasured trace gases to test the completeness of VOC measurements during field campaigns. A Comparative Reactivity Method (CRM) instrument was deployed in Dunkirk (France) to measure ambient OH reactivity during July 2014. An objective of this field campaign was to investigate the OH reactivity budget in different types of air masses, characterized by industrial, urban, and marine emissions, as well as different photochemical ages. Collocated measurements of non-methane hydrocarbons, oxygenated VOCs, and inorganic gases were also performed. OH reactivity measurements ranged from the detection limit of 3 s-1 up to 90 s-1, with a campaign average of approximately 14 s-1. Large discrepancies were observed between OH reactivity measurements and values calculated from measured trace gases, highlighting the presence of unmeasured reactive compounds. In this presentation, the measured and missing OH reactivity will be discussed regarding air mass origins and compositions. We will also present a novel approach that was implemented on the CRM instrument to identify part of the observed missing OH reactivity.

College Student Reporting Responses to Hypothetical and Actual Safety Concerns

ERIC Educational Resources Information Center

Hollister, Brandon A.; Scalora, Mario J.; Hoff, Sarah M.; Hodges, Heath J.; Marquez, Allissa

2017-01-01

Campus violence prevention often includes proactively reducing crime through noticing and resolving concerning situations. Within these efforts, interventions aimed at enhancing reporting have been considered necessary. The current study explored several reporting influences on college students' responses to hypothetical and actual campus safety…

Conflict Resolution among Preschool Children: The Appeal of Negotiation in Hypothetical Disputes.

ERIC Educational Resources Information Center

Iskandar, Niveen; And Others

1995-01-01

Using hypothetical puppet interviews, 48 preschool children were interviewed about their preferences for teacher methods of conflict intervention. Puppet vignettes contrasted conflict issue, peer status, and resolution strategy (negotiation, power assertion, and disengagement). Results showed that preschoolers preferred negotiation strategies over…

Scaffolding for Argumentation in Hypothetical and Theoretical Biology Concepts

ERIC Educational Resources Information Center

Weng, Wan-Yun; Lin, Yu-Ren; She, Hsiao-Ching

2017-01-01

The present study investigated the effects of online argumentation scaffolding on students' argumentation involving hypothetical and theoretical biological concepts. Two types of scaffolding were developed in order to improve student argumentation: continuous scaffolding and withdraw scaffolding. A quasi-experimental design was used with four…

How reinforcer type affects choice in economic games.

PubMed

Fantino, Edmund; Gaitan, Santino; Kennelly, Art; Stolarz-Fantino, Stephanie

2007-06-01

Behavioral economists stress that experiments on judgment and decision-making using economic games should be played with real money if the results are to have generality. Behavior analysts have sometimes disputed this contention and have reported results in which hypothetical rewards and real money have produced comparable outcomes. We review studies that have compared hypothetical and real money and discuss the results of two relevant experiments. In the first, using the Sharing Game developed in our laboratory, subjects' choices differed markedly depending on whether the rewards were real or hypothetical. In the second, using the Ultimatum and Dictator Games, we again found sharp differences between real and hypothetical rewards. However, this study also showed that time off from a tedious task could serve as a reinforcer every bit as potent as money. In addition to their empirical and theoretical contributions, these studies make the methodological point that meaningful studies may be conducted with economic games without spending money: time off from a tedious task can serve as a powerful reward.

Perceptions of, and Assistance Provided to, a Hypothetical Rape Victim: Differences Between Rape Disclosure Recipients and Nonrecipients

PubMed Central

Paul, Lisa A.; Kehn, Andre; Gray, Matt J.; Salapska-Gelleri, Joanna

2014-01-01

Objective Undergraduate rape disclosure recipients and nonrecipients’ sociodemographic and life experience variables, attitudes towards rape and responses to a hypothetical rape disclosure were compared to determine differences between them. Participants One-hundred-ninety-two undergraduates at three universities participated in this online survey between November 2011 – April 2012. Methods Participants reported on their rape myth acceptance (RMA) and personal direct and indirect (i.e., disclosure receipt) experiences with sexual assault. Participants also responded to a hypothetical rape disclosure. Results Disclosure recipients were more likely to report a victimization history, and less confusion and perceived ineffectiveness in helping the hypothetical victim. RMA and nonrecipient status predicted perceived victim responsibility; these variables and childhood victimization predicted confusion about helping. RMA also predicted perceived ineffectiveness of one’s helping behaviors. Victimization history and female gender predicted victim empathy. Conclusions These findings can inform sexual assault-related programming for undergraduates through the provision of targeted assistance and corrective information. PMID:24779405

Public house patrons' engagement in hypothetical sexual assault: a test of Alcohol Myopia Theory in a field setting.

PubMed

Flowe, Heather D; Stewart, Jade; Sleath, Emma R; Palmer, Francesca T

2011-01-01

Previous research has found that drinking establishments are often antecedent to sexual aggression outcomes. In this study, male participants were randomly selected from public houses (i.e., "pubs") and asked to imagine themselves in a hypothetical intimate encounter in which the female in the scenario stops consenting to sexual contact. Participants were given the option to continue making sexual advances up to and including sexual intercourse against the woman's will. It was hypothesized based on Alcohol Myopia Theory that participant blood alcohol concentration (BAC) levels would be associated with hypothetical sexual aggression when stereotypical cues of a woman's sexual availability (revealing clothing and alcohol use) were present in the scenario. Men's engagement in hypothetical sexual aggression was associated with BAC levels, but only when the woman was wearing revealing clothing. The sobriety of the female actor was not associated with sexual aggression. Results indicate that Alcohol Myopia Theory generalizes to a field setting. © 2011 Wiley Periodicals, Inc.

Statistical equivalence and test-retest reliability of delay and probability discounting using real and hypothetical rewards.

PubMed

Matusiewicz, Alexis K; Carter, Anne E; Landes, Reid D; Yi, Richard

2013-11-01

Delay discounting (DD) and probability discounting (PD) refer to the reduction in the subjective value of outcomes as a function of delay and uncertainty, respectively. Elevated measures of discounting are associated with a variety of maladaptive behaviors, and confidence in the validity of these measures is imperative. The present research examined (1) the statistical equivalence of discounting measures when rewards were hypothetical or real, and (2) their 1-week reliability. While previous research has partially explored these issues using the low threshold of nonsignificant difference, the present study fully addressed this issue using the more-compelling threshold of statistical equivalence. DD and PD measures were collected from 28 healthy adults using real and hypothetical $50 rewards during each of two experimental sessions, one week apart. Analyses using area-under-the-curve measures revealed a general pattern of statistical equivalence, indicating equivalence of real/hypothetical conditions as well as 1-week reliability. Exceptions are identified and discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Individual Differences in the Cortisol Responses of Neglected and Comparison Children

PubMed Central

Sullivan, Margaret Wolan; Bennett, David S.; Lewis, Michael

2014-01-01

Neglected children’s acute hypothalamic–pituitary–adrenal axis (HPA axis) reactivity in response to a laboratory visit was contrasted with that of a comparison group. The authors examined initial salivary cortisol response upon entering the laboratory and its trajectory following a set of tasks designed to elicit negative self-evaluation in 64 children (30 with a history of neglect and 34 demographically matched comparison children). Neglected, but not comparison, children showed higher initial cortisol responses. The cortisol response of both groups showed a decline from the sample taken at lab entry, with neglected children’s cortisol exhibiting steeper decline. The groups, however, did not differ in their mean cortisol levels at 20 and 35 min post-task. The results are interpreted in terms of the meaning of initial responses as a “baseline” and as evidence for neglected children’s heightened HPA-axis reactivity as either a reflection of differences in home levels or the consequence of stress/anxiety associated with arrival at the laboratory. PMID:22752003

Individual differences in the cortisol responses of neglected and comparison children.

PubMed

Sullivan, Margaret Wolan; Bennett, David S; Lewis, Michael

2013-02-01

Neglected children's acute hypothalamic-pituitary-adrenal axis (HPA axis) reactivity in response to a laboratory visit was contrasted with that of a comparison group. The authors examined initial salivary cortisol response upon entering the laboratory and its trajectory following a set of tasks designed to elicit negative self-evaluation in 64 children (30 with a history of neglect and 34 demographically matched comparison children). Neglected, but not comparison, children showed higher initial cortisol responses. The cortisol response of both groups showed a decline from the sample taken at lab entry, with neglected children's cortisol exhibiting steeper decline. The groups, however, did not differ in their mean cortisol levels at 20 and 35 min post-task. The results are interpreted in terms of the meaning of initial responses as a "baseline" and as evidence for neglected children's heightened HPA-axis reactivity as either a reflection of differences in home levels or the consequence of stress/anxiety associated with arrival at the laboratory.

Breathtaking TRP Channels: TRPA1 and TRPV1 in Airway Chemosensation and Reflex Control

PubMed Central

Bessac, Bret F.; Jordt, Sven-Eric

2009-01-01

New studies have revealed an essential role for TRPA1, a sensory neuronal TRP ion channel, in airway chemosensation and inflammation. TRPA1 is activated by chlorine, reactive oxygen species and noxious constituents of smoke and smog, initiating irritation and airway reflex responses. Together with TRPV1, the capsaicin receptor, TRPA1 may contribute to chemical hypersensitivity, chronic cough and airway inflammation in asthma, COPD and reactive airway dysfunction syndrome. PMID:19074743

Report of the Army Scientific Advisory Panel Ad Hoc Group on Fire Suppression

DTIC Science & Technology

1975-07-01

initially should be provided a nucleus of a seven- person technical staff composed of one 0-6 combat arme officer as Director, two senior behavioral ...If the suppressee perceives the fire as being reactive to his own behavior then the personal danger factor will be reinforced,1 Fire...that is not periodic hut also not reactive to his behavior may be like periodic fire in its personal threat except more difficult to

Electrostatic interactions during acidic phospholipid reactivation of DnaA protein, the Escherichia coli initiator of chromosomal replication.

PubMed

Kitchen, J L; Li, Z; Crooke, E

1999-05-11

The initiation of Escherichia coli chromosomal replication by DnaA protein is strongly influenced by the tight binding of the nucleotides ATP and ADP. Anionic phospholipids in a fluid bilayer promote the conversion of inactive ADP-DnaA protein to replicatively active ATP-DnaA protein in vitro, and thus likely play a key role in regulating DnaA activity. Previous studies have revealed that, during this reactivation, a specific region of DnaA protein inserts into the hydrophobic portion of the lipid bilayer in an acidic phospholipid-dependent manner. To elucidate the requirement for acidic phospholipids in the reactivation process, the contribution of electrostatic forces in the interaction of DnaA and lipid was examined. DnaA-lipid binding required anionic phospholipids, and DnaA-lipid binding as well as lipid-mediated release of DnaA-bound nucleotide were inhibited by increased ionic strength, suggesting the involvement of electrostatic interactions in these processes. As the vesicular content of acidic phospholipids was increased, both nucleotide release and DnaA-lipid binding increased in a linear, parallel manner. Given that DnaA-membrane binding, the insertion of DnaA into the membrane, and the consequent nucleotide release all require anionic phospholipids, the acidic headgroup may be necessary to recruit DnaA protein to the membrane for insertion and subsequent reactivation for replication.

Analyzing the Effect of Multi-fuel and Practical Constraints on Realistic Economic Load Dispatch using Novel Two-stage PSO

NASA Astrophysics Data System (ADS)

Chintalapudi, V. S.; Sirigiri, Sivanagaraju

2017-04-01

In power system restructuring, pricing the electrical power plays a vital role in cost allocation between suppliers and consumers. In optimal power dispatch problem, not only the cost of active power generation but also the costs of reactive power generated by the generators should be considered to increase the effectiveness of the problem. As the characteristics of reactive power cost curve are similar to that of active power cost curve, a nonconvex reactive power cost function is formulated. In this paper, a more realistic multi-fuel total cost objective is formulated by considering active and reactive power costs of generators. The formulated cost function is optimized by satisfying equality, in-equality and practical constraints using the proposed uniform distributed two-stage particle swarm optimization. The proposed algorithm is a combination of uniform distribution of control variables (to start the iterative process with good initial value) and two-stage initialization processes (to obtain best final value in less number of iterations) can enhance the effectiveness of convergence characteristics. Obtained results for the considered standard test functions and electrical systems indicate the effectiveness of the proposed algorithm and can obtain efficient solution when compared to existing methods. Hence, the proposed method is a promising method and can be easily applied to optimize the power system objectives.

Emotion Causes Targeted Forgetting of Established Memories

PubMed Central

Strange, Bryan A.; Kroes, Marijn C. W.; Fan, Judith E.; Dolan, Raymond J.

2010-01-01

Reconsolidation postulates that reactivation of a memory trace renders it susceptible to disruption by treatments similar to those that impair initial memory consolidation. Despite evidence that implicit, or non-declarative, human memories can be disrupted at retrieval, a convincing demonstration of selective impairment in retrieval of target episodic memories following reactivation is lacking. In human subjects, we demonstrate that if reactivation of a verbal memory, through successful retrieval, is immediately followed by an emotionally aversive stimulus, a significant impairment is evident in its later recall. This effect is time-dependent and persists for at least 6 days. Thus, in line with a reconsolidation hypothesis, established human episodic memories can be selectively impaired following their retrieval. PMID:21191439

Memory reactivation during rest supports upcoming learning of related content.

PubMed

Schlichting, Margaret L; Preston, Alison R

2014-11-04

Although a number of studies have highlighted the importance of offline processes for memory, how these mechanisms influence future learning remains unknown. Participants with established memories for a set of initial face-object associations were scanned during passive rest and during encoding of new related and unrelated pairs of objects. Spontaneous reactivation of established memories and enhanced hippocampal-neocortical functional connectivity during rest was related to better subsequent learning, specifically of related content. Moreover, the degree of functional coupling during rest was predictive of neural engagement during the new learning experience itself. These results suggest that through rest-phase reactivation and hippocampal-neocortical interactions, existing memories may come to facilitate encoding during subsequent related episodes.

Memory reactivation during rest supports upcoming learning of related content

PubMed Central

Schlichting, Margaret L.; Preston, Alison R.

2014-01-01

Although a number of studies have highlighted the importance of offline processes for memory, how these mechanisms influence future learning remains unknown. Participants with established memories for a set of initial face–object associations were scanned during passive rest and during encoding of new related and unrelated pairs of objects. Spontaneous reactivation of established memories and enhanced hippocampal–neocortical functional connectivity during rest was related to better subsequent learning, specifically of related content. Moreover, the degree of functional coupling during rest was predictive of neural engagement during the new learning experience itself. These results suggest that through rest-phase reactivation and hippocampal–neocortical interactions, existing memories may come to facilitate encoding during subsequent related episodes. PMID:25331890

Lipids, inflammation, and chronic kidney disease: a SHARP perspective.

PubMed

Waters, David D; Vogt, Liffert

2018-04-01

Accumulating evidence indicates that inflammation plays a role in the initiation and progression of chronic kidney disease. In the Study of Heart and Renal Protection (SHARP) trial, higher baseline C-reactive protein and higher baseline low-density lipoprotein cholesterol levels were both associated with a higher risk of cardiovascular events, but higher baseline C-reactive protein levels were also associated with a higher risk of nonvascular events. Simvastatin/ezetimibe reduced cardiovascular events independent of baseline C-reactive protein levels. However, this observation does not exclude inflammation as a causal factor for cardiovascular disease development in chronic kidney disease patients. Copyright © 2018 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Emotion causes targeted forgetting of established memories.

PubMed

Strange, Bryan A; Kroes, Marijn C W; Fan, Judith E; Dolan, Raymond J

2010-01-01

Reconsolidation postulates that reactivation of a memory trace renders it susceptible to disruption by treatments similar to those that impair initial memory consolidation. Despite evidence that implicit, or non-declarative, human memories can be disrupted at retrieval, a convincing demonstration of selective impairment in retrieval of target episodic memories following reactivation is lacking. In human subjects, we demonstrate that if reactivation of a verbal memory, through successful retrieval, is immediately followed by an emotionally aversive stimulus, a significant impairment is evident in its later recall. This effect is time-dependent and persists for at least 6 days. Thus, in line with a reconsolidation hypothesis, established human episodic memories can be selectively impaired following their retrieval.

The Mechanical Response of Advanced Claddings during Proposed Reactivity Initiated Accident Conditions

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

Cinbiz, Mahmut N; Brown, Nicholas R; Terrani, Kurt A

2017-01-01

This study investigates the failure mechanisms of advanced nuclear fuel cladding of FeCrAl at high-strain rates, similar to design basis reactivity initiated accidents (RIA). During RIA, the nuclear fuel cladding was subjected to the plane-strain to equibiaxial tension strain states. To achieve those accident conditions, the samples were deformed by the expansion of high strength Inconel alloy tube under pre-specified pressure pulses as occurring RIA. The mechanical response of the advanced claddings was compared to that of hydrided zirconium-based nuclear fuel cladding alloy. The hoop strain evolution during pressure pulses were collected in situ; the permanent diametral strains of bothmore » accident tolerant fuel (ATF) claddings and the current nuclear fuel alloys were determined after rupture.« less

Transport of secondary electrons and reactive species in ion tracks

NASA Astrophysics Data System (ADS)

Surdutovich, Eugene; Solov'yov, Andrey V.

2015-08-01

The transport of reactive species brought about by ions traversing tissue-like medium is analysed analytically. Secondary electrons ejected by ions are capable of ionizing other molecules; the transport of these generations of electrons is studied using the random walk approximation until these electrons remain ballistic. Then, the distribution of solvated electrons produced as a result of interaction of low-energy electrons with water molecules is obtained. The radial distribution of energy loss by ions and secondary electrons to the medium yields the initial radial dose distribution, which can be used as initial conditions for the predicted shock waves. The formation, diffusion, and chemical evolution of hydroxyl radicals in liquid water are studied as well. COST Action Nano-IBCT: Nano-scale Processes Behind Ion-Beam Cancer Therapy.

Water World Artist Concept

NASA Image and Video Library

2017-04-12

This artist's concept shows a hypothetical planet covered in water around the binary star system of Kepler-35A and B. In a 2017 study in the journal Nature Communications, researchers investigating the climates of exoplanets determined that this hypothetical planet could be habitable, depending on its distance from the two stars. On the far edge of the habitable zone, the hypothetical water-covered planet would have a lot of variation in its surface temperatures. But closer to the stars, near the inner edge of the habitable zone, the global average surface temperatures on the same planet would stay almost constant. https://photojournal.jpl.nasa.gov/catalog/PIA21470

Moral emotions and moral judgments in children's narratives: comparing real-life and hypothetical transgressions.

PubMed

Gutzwiller-Helfenfinger, Eveline; Gasser, Luciano; Malti, Tina

2010-01-01

How children make meaning of their own social experiences in situations involving moral issues is central to their subsequent affective and cognitive moral learning. Our study of young children's narratives describing their interpersonal conflicts shows that the emotions and judgments constructed in the course of these real-life narratives differ from the emotions and judgments generated in the context of hypothetical transgressions. In the narratives, all emotions mentioned spontaneously were negative. In contrast, emotions attributed in the interview part covered a broader spectrum. One's own real-life transgressions were judged less severe and more justified than hypothetical transgressions. © Wiley Periodicals, Inc.

An Efficient Method to Design Premature End-of-Life Trajectories: A Hypothetical Alternate Fate for Cassini

NASA Technical Reports Server (NTRS)

Vaquero, Mar; Senent, Juan

2015-01-01

What would happen if, hypothetically, the highly successful Cassini mission were to end prematurely due to lack of propellant or sudden subsystem failure? A solid plan to quickly produce a solution for any given scenario, regardless of where the spacecraft is along its reference path, must be in place to safely dispose of the spacecraft and meet all planetary protection requirements. As a contingency plan for this hypothetical situation, a method to design viable high-fidelity terminating trajectories based on a hybrid approach that exploits two-body and three-body flyby transfers combined with a numerical optimization scheme is detailed in this paper.

Historical and hypothetical future sedimentation and water storage in Kajakai Reservoir, central Afghanistan

USGS Publications Warehouse

Vining, Kevin C.; Vecchia, Aldo V.

2008-01-01

Sedimentation has reduced water storage in Kajakai Reservoir. If current sedimentation rates continue, hypothetical future reservoir water volumes at the spillway elevation of 1,033.5 meters could be reduced about 22 percent from 2006 to 2057. Even if the spillway elevation is raised to 1,045 meters, a severe drought could result in large multiyear irrigation-supply deficits in which reservoir water levels remain below 1,022 meters for more than 4 years. Hypothetical climate change and sedimentation could result in greater water-supply deficits. The chance of having sufficient water supplies in Kajakai Reservoir during the worst month is about 47 percent.

75 FR 81456 - Hybrid Retirement Plans; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

... defined benefit plan. * * * * * (b) * * * (1) * * * (ii) * * * (A) In general. Except as provided in... benefit of participants who are younger than age 55 is expressed as the current balance of a hypothetical... annual compensation formula and a benefit that is based on the balance of a hypothetical account, then...

Workers With AIDS: Hypothetical Supervisors' Willingness to Make EAP Referrals.

ERIC Educational Resources Information Center

Gerstein, Lawrence H.; Duffey, Kim

1992-01-01

Investigated willingness of 86 hypothetical supervisors (86 students enrolled in graduate-level business classes) to refer subordinates with 5 types of problems (Acquired Immune Deficiency Syndrome, human immunodeficiency virus-positive status, alcohol abuse, cocaine abuse, job impairment) to Employee Assistance Programs. More severe worker's…

Sharing, Discounting, and Selfishness: A Japanese-American Comparison

ERIC Educational Resources Information Center

Ito, Masato; Saeki, Daisuke; Green, Leonard

2011-01-01

Social discounting rates were compared between Japanese and American college students. In a series of psychophysical questionnaire tasks, participants chose between a hypothetical unshared monetary reward and a hypothetical monetary reward to be shared with other people (relatives or strangers), to determine amounts of the unshared reward…

Measurements of total OH reactivity during PROPHET-AMOS 2016

NASA Astrophysics Data System (ADS)

Rickly, P.; Sakowski, J.; Bottorff, B.; Lew, M.; Stevens, P. S.; Sklaveniti, S.; Locoge, N.; Dusanter, S.

2017-12-01

As one of the main oxidant in the atmosphere, the hydroxyl radical (OH) initiates the oxidation of volatile organic compounds that can lead to the formation of ozone and secondary organic aerosols. Understanding both the sources and sinks of OH is therefore important to address issues related to air quality and climate change. Measurements of total OH reactivity can provide an important test of our understanding of the OH radical budget. Recent measurements of total reactivity in many environments have been greater than calculated based on the measured concentration of VOCs, suggesting that important OH sinks in these environments are not well characterized. Measurements of total OH reactivity were performed in a forested environment during the PROPHET - AMOS field campaign (Program for Research on Oxidants: PHotochemisty, Emissions, and Transport - Atmospheric Measurements of Oxidants in Summer) using the Comparative Reactivity Method (CRM) and the Total OH Loss Rate Method (TOHLM). The site is characterized by large emissions of isoprene and monoterpenes and low anthropogenic influence. Measurements of total OH reactivity using these two techniques agree to within their respective uncertainties, giving confidence in the measured OH reactivity. In addition, measurements of trace gases (VOCs, NOx, O3) were used to perform a comprehensive apportionment of OH sinks. These measurements are used in a chemical model using the Master Chemical Mechanism to calculate the expected OH reactivity. The results will be compared to previous measurements of total OH reactivity at this site.

The physiological correlates of children's emotions in contexts of moral transgression.

PubMed

Malti, Tina; Colasante, Tyler; Zuffianò, Antonio; de Bruine, Marieke

2016-02-01

Heightened attention to sociomoral conflicts and arousal at the prospect of committing moral transgressions are thought to increase the likelihood of negatively valenced moral emotions (NVMEs; e.g., guilt) in children. Here, we tested this biphasic model of moral emotions with a psychophysiological framework. For a series of vignettes depicting moral transgressions, 5- and 8-year-olds (N=138) were asked to anticipate their emotions as hypothetical victimizers. Their responses were coded for the presence and intensity of NVMEs. In addition, their heart rate (HR) was calculated for three intervals of interest: a baseline period, the presentation of vignettes, and the anticipation of emotions following vignettes. We used multilevel modeling to examine how change in children's HR across these intervals related to the intensity of their NVMEs. Those who experienced greater HR deceleration from baseline to vignettes and greater acceleration from vignettes to anticipated emotions reported more intense NVMEs. We discuss the potential attention- and arousal-related processes behind children's physiological reactivity and anticipated emotions in contexts of moral transgression. Copyright © 2015 Elsevier Inc. All rights reserved.

Ammonium fluoride-activated synthesis of cubic δ-TaN nanoparticles at low temperatures

NASA Astrophysics Data System (ADS)

Lee, Young-Jun; Kim, Dae-Young; Lee, Kap-Ho; Han, Moon-Hee; Kang, Kyoung-Soo; Bae, Ki-Kwang; Lee, Jong-Hyeon

2013-03-01

Cubic delta-tantalum nitride ( δ-TaN) nanoparticles were selectively prepared using a K2TaF7 + (5 + k) NaN3 + kNH4F reactive mixture ( k being the number of moles of NH4F) via a combustion process under a nitrogen pressure of 2.0 MPa. The combustion temperature, when plotted as a function of the number of moles of NH4F used, was in the range of 850°C to 1,170°C. X-ray diffraction patterns revealed the formation of cubic δ-TaN nanoparticles at 850°C to 950°C when NH4F is used in an amount of 2.0 mol (or greater) in the combustion experiment. Phase pure cubic δ-TaN synthesized at k = 4 exhibited a specific surface area of 30.59 m2/g and grain size of 5 to 10 nm, as estimated from the transmission electron microscopy micrograph. The role of NH4F in the formation process of δ-TaN is discussed with regard to a hypothetical reaction mechanism.

The paradox of caffeine-zolpidem interaction: a network analysis.

PubMed

Myslobodsky, Michael

2009-10-01

A widely prescribed and potent short-acting hypnotic, zolpidem has become the mainstay for the treatment of middle-of-the-night sleeplessness. It is expected to be antagonized by caffeine. Paradoxically, in some cases caffeine appears to slightly enhance zolpidem sedation. The pharmacokinetic and pharmacodynamic nature of this odd effect remains unexplored. The purpose of this study is to reproduce a hypothetical molecular network recruited by caffeine when co-administered with zolpidem using Ingenuity Pathway Analysis. Thus generated, network drew attention to several possible contributors to caffeine sedation, such as tachykinin precursor 1, cannabinoid, and GABA receptors. The present overview is centered on the possibility that caffeine potentiation of zolpidem sedation does not involve a centralized interaction of specific neurotransmitters, but rather is contributed by its antioxidant capacity. It is proposed that by modifying the cellular redox state, caffeine ultimately reduces the pool of reactive oxygen species, thereby increasing the bioavailability of endogenous melatonin for interaction with zolpidem. This side effect of caffeine encourages further studies of multiple antioxidants as an attractive way to potentially increasing somnolence.

Dynamics of the microglial/amyloid interaction indicate a role in plaque maintenance.

PubMed

Bolmont, Tristan; Haiss, Florent; Eicke, Daniel; Radde, Rebecca; Mathis, Chester A; Klunk, William E; Kohsaka, Shinichi; Jucker, Mathias; Calhoun, Michael E

2008-04-16

Microglial cells aggregate around amyloid plaques in Alzheimer's disease, but, despite their therapeutic potential, various aspects of their reactive kinetics and role in plaque pathogenesis remain hypothetical. Through use of in vivo imaging and quantitative morphological measures in transgenic mice, we demonstrate that local resident microglia rapidly react to plaque formation by extending processes and subsequently migrating toward plaques, in which individual transformed microglia somata remain spatially stable for weeks. The number of plaque-associated microglia increased at a rate of almost three per plaque per month, independent of plaque volume. Larger plaques were surrounded by larger microglia, and a subset of plaques changed in size over time, with an increase or decrease related to the volume of associated microglia. Far from adopting a more static role, plaque-associated microglia retained rapid process and membrane movement at the plaque/glia interface. Microglia internalized systemically injected amyloid-binding dye at a much higher rate in the vicinity of plaques. These results indicate a role for microglia in plaque maintenance and provide a model with multiple targets for therapeutic intervention.

Dynamics of the Microglial/Amyloid Interaction Indicate a Role in Plaque Maintenance

PubMed Central

Bolmont, Tristan; Haiss, Florent; Eicke, Daniel; Radde, Rebecca; Mathis, Chester A.; Klunk, William E.; Kohsaka, Shinichi; Jucker, Mathias

2008-01-01

Microglial cells aggregate around amyloid plaques in Alzheimer's disease, but, despite their therapeutic potential, various aspects of their reactive kinetics and role in plaque pathogenesis remain hypothetical. Through use of in vivo imaging and quantitative morphological measures in transgenic mice, we demonstrate that local resident microglia rapidly react to plaque formation by extending processes and subsequently migrating toward plaques, in which individual transformed microglia somata remain spatially stable for weeks. The number of plaque-associated microglia increased at a rate of almost three per plaque per month, independent of plaque volume. Larger plaques were surrounded by larger microglia, and a subset of plaques changed in size over time, with an increase or decrease related to the volume of associated microglia. Far from adopting a more static role, plaque-associated microglia retained rapid process and membrane movement at the plaque/glia interface. Microglia internalized systemically injected amyloid-binding dye at a much higher rate in the vicinity of plaques. These results indicate a role for microglia in plaque maintenance and provide a model with multiple targets for therapeutic intervention. PMID:18417708

Ehlers-Danlos Syndrome associated with cardiomyopathy hypertrophic obstructive*

PubMed Central

Pinto, Raimundo José Almeida de Oliveira; dos Santos, Adaílton Araújo; Azevedo, Mablo de Castro; Meira, Saulo Sacramento

2015-01-01

Ehlers-Danlos syndrome is a rare clinical condition caused by a genetic change that results in the formation of structurally or functionally altered collagen. The clinical manifestations are varied, being the most obvious skin hypermotility and increased joint flexibility, although other systems - such as cardiovascular, respiratory and neurological - may also be affected. This paper presents the report of a patient who sought medical attention with complaints of atypical chest pain. Clinical evaluation enabled hypothetical diagnosis of hypertrophic obstructive cardiomyopathy and Ehlers-Danlos syndrome. Initial electrocardiogram, echocardiogram and 24 hours holter allowed the confirmation of the first hypothesis. A skin biopsy performed later associated clinical data and confirmed the second hypothesis. PMID:26312722

Preliminary investigation of parasitic radioisotope production using the LANL IPF secondary neutron flux

NASA Astrophysics Data System (ADS)

Engle, J. W.; Kelsey, C. T.; Bach, H.; Ballard, B. D.; Fassbender, M. E.; John, K. D.; Birnbaum, E. R.; Nortier, F. M.

2012-12-01

In order to ascertain the potential for radioisotope production and material science studies using the Isotope Production Facility at Los Alamos National Lab, a two-pronged investigation has been initiated. The Monte Carlo for Neutral Particles eXtended (MCNPX) code has been used in conjunction with the CINDER 90 burnup code to predict neutron flux energy distributions as a result of routine irradiations and to estimate yields of radioisotopes of interest for hypothetical irradiation conditions. A threshold foil activation experiment is planned to study the neutron flux using measured yields of radioisotopes, quantified by HPGe gamma spectroscopy, from representative nuclear reactions with known thresholds up to 50 MeV.

Environmental sustainability comparison of a hypothetical pneumatic waste collection system and a door-to-door system.

PubMed

Punkkinen, Henna; Merta, Elina; Teerioja, Nea; Moliis, Katja; Kuvaja, Eveliina

2012-10-01

Waste collection is one of the life cycle phases that influence the environmental sustainability of waste management. Pneumatic waste collection systems represent a new way of arranging waste collection in densely populated urban areas. However, limited information is available on the environmental impacts of this system. In this study, we compare the environmental sustainability of conventional door-to-door waste collection with its hypothetical pneumatic alternative. Furthermore, we analyse whether the size of the hypothetical pneumatic system, or the number of waste fractions included, have an impact on the results. Environmental loads are calculated for a hypothetical pneumatic waste collection system modelled on an existing dense urban area in Helsinki, Finland, and the results are compared to those of the prevailing, container-based, door-to-door waste collection system. The evaluation method used is the life-cycle inventory (LCI). In this study, we report the atmospheric emissions of greenhouse gases (GHG), SO(2) and NO(x). The results indicate that replacing the prevailing system with stationary pneumatic waste collection in an existing urban infrastructure would increase total air emissions. Locally, in the waste collection area, emissions would nonetheless diminish, as collection traffic decreases. While the electricity consumption of the hypothetical pneumatic system and the origin of electricity have a significant bearing on the results, emissions due to manufacturing the system's components prove decisive. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tick-Tock Goes the Croc: A High-Density EEG Study of Risk-Reactivity and Binge-Drinking.

PubMed

Kiat, John E; Cheadle, Jacob E

2018-05-31

Links between individual differences in risk processing and high-risk behaviors such as binge drinking have long been the focus of active research. However, investigations in this area almost exclusively utilize decision-making focused paradigms. This emphasis makes it difficult to assess links between risk behaviors and raw risk reactivity independent of decision and feedback processes. A deeper understanding of this association has the potential to shed light on the role of risk reactivity in high-risk behavior susceptibility. To contribute towards this aim, this study utilizes a popular risk-taking game, the crocodile dentist, to assess links between individual differences in decision-free risk-reactivity and reported binge drinking frequency levels. In this task, participants engage in a series of decision-free escalating risk responses. Risk-reactivity was assessed by measuring Late Positive Potential responses towards risk-taking action initiation cues using high-density 256-Channel EEG. The results indicate that, after controlling for overall alcohol consumption frequency, higher rates of reported binge drinking are associated with both increased general risk-taking responsivity and increased risk-reactivity escalation as a function of risk level. These findings highlight intriguing links between risk reactivity and binge drinking frequency, making key contributions in the areas of risk-taking and affective science.

Maternal, Infant Characteristics, Breastfeeding Techniques, and Initiation: Structural Equation Modeling Approaches

PubMed Central

Htun, Tha Pyai; Lim, Peng Im; Ho-Lim, Sarah

2015-01-01

Objectives The aim of this study was to examine the relationships among maternal and infant characteristics, breastfeeding techniques, and exclusive breastfeeding initiation in different modes of birth using structural equation modeling approaches. Methods We examined a hypothetical model based on integrating concepts of a breastfeeding decision-making model, a breastfeeding initiation model, and a social cognitive theory among 952 mother-infant dyads. The LATCH breastfeeding assessment tool was used to evaluate breastfeeding techniques and two infant feeding categories were used (exclusive and non-exclusive breastfeeding). Results Structural equation models (SEM) showed that multiparity was significantly positively associated with breastfeeding techniques and the jaundice of an infant was significantly negatively related to exclusive breastfeeding initiation. A multigroup analysis in the SEM showed no difference between the caesarean section and vaginal delivery groups estimates of breastfeeding techniques on exclusive breastfeeding initiation. Breastfeeding techniques were significantly positively associated with exclusive breastfeeding initiation in the entire sample and in the vaginal deliveries group. However, breastfeeding techniques were not significantly associated with exclusive breastfeeding initiation in the cesarean section group. Maternal age, maternal race, gestations, birth weight of infant, and postnatal complications had no significant impacts on breastfeeding techniques or exclusive breastfeeding initiation in our study. Overall, the models fitted the data satisfactorily (GFI = 0.979–0.987; AGFI = 0.951–0.962; IFI = 0.958–0.962; CFI = 0.955–0.960, and RMSEA = 0.029–0.034). Conclusions Multiparity and jaundice of an infant were found to affect breastfeeding technique and exclusive breastfeeding initiation respectively. Breastfeeding technique was related to exclusive breastfeeding initiation according to the mode of birth. This relationship implies the importance of early effective interventions among first-time mothers with jaundice infants in improving breastfeeding techniques and promoting exclusive breastfeeding initiation. PMID:26566028

Simulation of groundwater and surface-water interaction and effects of pumping in a complex glacial-sediment aquifer, east central Massachusetts

USGS Publications Warehouse

Eggleston, Jack R.; Carlson, Carl S.; Fairchild, Gillian M.; Zarriello, Phillip J.

2012-01-01

The effects of groundwater pumping on surface-water features were evaluated by use of a numerical groundwater model developed for a complex glacial-sediment aquifer in northeastern Framingham, Massachusetts, and parts of surrounding towns. The aquifer is composed of sand, gravel, silt, and clay glacial-fill sediments up to 270 feet thick over an irregular fractured bedrock surface. Surface-water bodies, including Cochituate Brook, the Sudbury River, Lake Cochituate, Dudley Pond, and adjoining wetlands, are in hydraulic connection with the aquifer and can be affected by groundwater withdrawals. Groundwater and surface-water interaction was simulated with MODFLOW-NWT under current conditions and a variety of hypothetical pumping conditions. Simulations of hypothetical pumping at reactivated water supply wells indicate that captured groundwater would decrease baseflow to the Sudbury River and induce recharge from Lake Cochituate. Under constant (steady-state) pumping, induced groundwater recharge from Lake Cochituate was equal to about 32 percent of the simulated pumping rate, and flow downstream in the Sudbury River decreased at the same rate as pumping. However, surface water responded quickly to pumping stresses. When pumping was simulated for 1 month and then stopped, streamflow depletions decreased by about 80 percent within 2 months and by about 90 percent within about 4 months. The fast surface water response to groundwater pumping offers the potential to substantially reduce streamflow depletions during periods of low flow, which are of greatest concern to the ecological integrity of the river. Results indicate that streamflow depletion during September, typically the month of lowest flow, can be reduced by 29 percent by lowering the maximum pumping rates to near zero during September. Lowering pumping rates for 3 months (July through September) reduces streamflow depletion during September by 79 percent as compared to constant pumping. These results demonstrate that a seasonal or streamflow-based groundwater pumping schedule can reduce the effects of pumping during periods of low flow.

Economics of Home Monitoring for Apnea in Late Preterm Infants.

PubMed

Montenegro, Brian L; Amberson, Michael; Veit, Lauren; Freiberger, Christina; Dukhovny, Dmitry; Rhein, Lawrence M

2017-01-01

Apnea of prematurity affects a small proportion but large absolute number of late preterm infants, with out-patient management variably utilized despite relative clinical equipoise and potential for improved cost-effectiveness. Over a 5-y period, from 2009 to 2013, infants born at ≥34 weeks gestational age at a level IIIB academic center in Boston, Massachusetts, with discharge-delaying apnea, bradycardia, and desaturation (ABD) events were identified. In-patient costs for discharge-delaying ABD events were compared with hypothetical out-patient management. Out-patient costs took into account 4-10 d of in-patient observation for ABD events before caffeine initiation, 3-5 d of additional in-patient observation before discharge, daily caffeine until 43 weeks corrected gestational age, home pulse oximetry monitoring until 44 weeks corrected gestational age, and consideration of variable readmission rates ranging from 0 to 10%. A total of 425 late preterm and term infants were included in our analysis. Utilization of hypothetical out-patient management resulted in cost savings per eligible patient ranging from $2,422 to $62, dependent upon variable periods of in-patient observation. Sensitivity analysis demonstrated few instances of decreased relative cost-effectiveness. Out-patient management of discharge-delaying ABD events in a late preterm and term population was a cost-effective alternative to prolonged in-patient observation. Copyright © 2017 by Daedalus Enterprises.

Risk factors for failed reactivation of a labor epidural for postpartum tubal ligation: a prospective, observational study.

PubMed

Powell, Mark F; Wellons, Douglas D; Tran, Steve F; Zimmerman, John M; Frölich, Michael A

2016-12-01

To determine specific risk factors that increase the failure rate of labor epidurals reactivated for use as a surgical block for postpartum tubal ligation. Prospective, observational study. Labor and delivery suite and operating rooms at the Women and Infants Center. One hundred patients undergoing postpartum tubal ligation with an existing labor epidural that is documented to be within 2 cm of initial placement. Body mass index, patient satisfaction with her epidural during labor and delivery, time from delivery to reactivation for tubal ligation, depth to loss of resistance, and the need for top-ups during labor were recorded preoperatively. Failure to reactivate was recorded and defined as any patient that (1) did not achieve a T 6 level to pinprick, (2) had perceived pain (pain score >3) that required administration of an intravenous opioid or local anesthetic infiltration, or (3) required conversion to general anesthesia. The overall success rate of reactivation was 78%. Significant risk factors for failure to reactivate were (1) poor patient satisfaction (P = .016), (2) increased time from delivery to reactivation (P = .044), and (3) the need for top-ups during labor and delivery (P = .032). Poor satisfaction score of the epidural during labor and delivery, increasing time from delivery to epidural reactivation for tubal ligation, and the need for top-ups during labor and delivery increase the incidence of reactivation failure. No correlation was found with body mass index or loss of resistance and failure to reactivate. Copyright © 2016 Elsevier Inc. All rights reserved.

Oxidative stress and inflammatory response increase during coronary artery bypass grafting with extracorporeal circulation.

PubMed

Melek, Flora Eli; Baroncini, Liz Andréa Villela; Repka, João Carlos Domingus; Nascimento, Celso Soares; Précoma, Dalton Bertolim

2012-01-01

Thiobarbituric acid-reactive substance is a marker of oxidative stress and has cytotoxic and genotoxic actions. C- reactive protein is used to evaluate the acute phase of inflammatory response. To assess the thiobarbituric acid-reactive substance and C-reactive protein levels during extracorporeal circulation in patients submitted to cardiopulmonary bypass. Twenty-five consecutive surgical patients (16 men and nine women; mean age 61.2 ± 9.7 years) with severe coronary artery disease diagnosed by angiography scheduled for myocardial revascularization surgery with extracorporeal circulation were selected. Blood samples were collected immediately before initializing extracorporeal circulation, T0; in 10 minutes, T10; and in 30 minutes, T30. The thiobarbituric acid-reactive substance levels increased after extracorporeal circulation (P=0.001), with average values in T0=1.5 ± 0.07; in T10=5.54 ± 0.35; and in T30=3.36 ± 0.29 mmoles/mg of serum protein. The C-reactive protein levels in T0 were negative in all samples; in T10 average was 0.96 ± 0.7 mg/dl; and in T30 average was 0.99 ± 0.76 mg/dl. There were no significant differences between the dosages in T10 and T30 (P=0.83). C-reactive protein and thiobarbituric acid-reactive substance plasma levels progressively increased during extracorporeal circulation, with maximum values of thiobarbituric acid-reactive substance at 10 min and of C-reactive protein at 30 min. It suggests that there are an inflammatory response and oxidative stress during extracorporeal circulation.

Simulation Study on Jet Formability and Damage Characteristics of a Low-Density Material Liner

PubMed Central

Tang, Wenhui; Ran, Xianwen

2018-01-01

The shaped charge tandem warhead is an effective weapon against the ERA (explosive reactive armor). Whether the pre-warhead can reliably initiate the ERA directly determines the entire performance of the tandem warhead. The existing shaped charge pre-warhead mostly adopts a metal shaped jet, which effectively initiates the ERA, but interferes the main shaped jet. This article, on the other hand, explores the possibility of producing a pre-warhead using a low-density material as the liner. The nonlinear dynamic analysis software Autodyn-2D is used to simulate and compare three kinds of low-density shaped jets, including floatglass, Lucite, and Plexiglas, to the copper shaped jet in the effectiveness of impacting ERA. Based on the integrative criteria (including u-d initiation criterion, explosive reactive degree, explosive pressure, and particle velocity of the panels), it can be determined whether the low-density shaped jet can reliably initiate the sandwich charge. The results show that the three kinds of low-density shaped jets can not only initiate the reaction armor, but are also superior to the existing copper shaped jet in ductility, jet tip velocity, jet tip diameter, and the mass; namely, it is feasible to use the low-density material shaped jet to destroy the ERA. PMID:29300351

Tuning the Ignition Performance of a Microchip Initiator by Integrating Various Al/MoO3 Reactive Multilayer Films on a Semiconductor Bridge.

PubMed

Xu, Jianbing; Tai, Yu; Ru, Chengbo; Dai, Ji; Ye, Yinghua; Shen, Ruiqi; Zhu, Peng

2017-02-15

Reactive multilayer films (RMFs) can be integrated into semiconducting electronic structures with the use of microelectromechanical systems (MEMS) technology and represent potential applications in the advancement of microscale energy-demanding systems. In this study, aluminum/molybdenum trioxide (Al/MoO 3 )-based RMFs with different modulation periods were integrated on a semiconductor bridge (SCB) using a combination of an image reversal lift-off process and magnetron sputtering technology. This produced an energetic semiconductor bridge (ESCB)-chip initiator with controlled ignition performance. The effects of the Al/MoO 3 RMFs with different modulation periods on ignition properties of the ESCB initiator were then systematically investigated in terms of flame duration, maximum flame area, and the reaction ratio of the RMFs. These microchip initiators achieved flame durations of 60-600 μs, maximum flame areas of 2.85-17.61 mm 2 , and reaction ratios of ∼14-100% (discharged with 47 μF/30 V) by simply changing the modulation periods of the Al/MoO 3 RMFs. This behavior was also consistent with a one-dimensional diffusion reaction model. The microchip initiator exhibited a high level of integration and proved to have tuned ignition performance, which can potentially be used in civilian and military applications.

NASA Glenn's Engine Components Research Lab, Cell 2B, Reactivated to Support the U.S. Army Research Laboratory T700 Engine Test

NASA Technical Reports Server (NTRS)

Beltran, Luis R.; Griffin, Thomas A.

2004-01-01

The U.S. Army Vehicle Technology Directorate at the NASA Glenn Research Center has been directed by their parent command, the U.S. Army Research Laboratory (ARL), to demonstrate active stall technology in a turboshaft engine as the next step in transitioning this technology to the Army and aerospace industry. Therefore, the Vehicle Technology Directorate requested the reactivation of Glenn's Engine Components Research Lab, Cell 2B, (ECRL 2B). They wanted to test a T700 engine that had been used previously for turboshaft engine research as a partnership between the Army and NASA on small turbine engine research. ECRL 2B had been placed in standby mode in 1997. Glenn's Testing Division initiated reactivation in May 2002 to support the new research effort, and they completed reactivation and improvements in September 2003.

Study of thermite mixtures consolidated by cold gas dynamic spray process

NASA Astrophysics Data System (ADS)

Bacciochini, Antoine; Maines, Geoffrey; Poupart, Christian; Radulescu, Matei; Jodoin, Bertrand; Lee, Julian

2013-06-01

The present study focused on the cold gas dynamic spray process for manufacturing finely structured energetic materials with high reactivity, vanishing porosity, as well as structural integrity and arbitrary shape. The experiments have focused the reaction between the aluminum and metal oxides, such as Al-CuO and Al-MoO3 systems. To increase the reactivity, an initial mechanical activation was achieved through interrupted ball milling. The consolidation of the materials used the supersonic cold gas spray technique, where the particles are accelerated to high speeds and consolidated via plastic deformation upon impact, forming activated nano-composites in arbitrary shapes with close to zero porosity. This technique permits to retain the feedstock powder micro-structure and prevents any reactions during the consolidation phase. Reactivity of mixtures has been investigated through flame propagation analysis on cold sprayed samples and compacted powder mixture. Deflagration tests showed the influence of porosity on the reactivity.

Electron density reactivity indexes of the tautomeric/ionization forms of thiamin diphosphate.

PubMed

Jaña, Gonzalo A; Delgado, Eduardo J

2013-09-01

The generation of the highly reactive ylide in thiamin diphosphate catalysis is analyzed in terms of the nucleophilicity of key atoms, by means of density functional calculations at X3LYP/6-31++G(d,p) level of theory. The Fukui functions of all tautomeric/ionization forms are calculated in order to assess their reactivity. The results allow to conclude that the highly conserved glutamic residue does not protonate the N1' atom of the pyrimidyl ring, but it participates in a strong hydrogen bonding, stabilizing the eventual negative charge on the nitrogen, in all forms involved in the ylide generation. This condition provides the necessary reactivity on key atoms, N4' and C2, to carry out the formation of the ylide required to initiate the catalytic cycle of ThDP-dependent enzymes. This study represents a new approach for the ylide formation in ThDP catalysis.

Tracing the plasma interactions for pulsed reactive crossed-beam laser ablation

NASA Astrophysics Data System (ADS)

Chen, Jikun; Stender, Dieter; Pichler, Markus; Döbeli, Max; Pergolesi, Daniele; Schneider, Christof W.; Wokaun, Alexander; Lippert, Thomas

2015-10-01

Pulsed reactive crossed-beam laser ablation is an effective technique to govern the chemical activity of plasma species and background molecules during pulsed laser deposition. Instead of using a constant background pressure, a gas pulse with a reactive gas, synchronized with the laser beam, is injected into vacuum or a low background pressure near the ablated area of the target. It intercepts the initially generated plasma plume, thereby enhancing the physicochemical interactions between the gaseous environment and the plasma species. For this study, kinetic energy resolved mass-spectrometry and time-resolved plasma imaging were used to study the physicochemical processes occurring during the reactive crossed beam laser ablation of a partially 18O substituted La0.6Sr0.4MnO3 target using oxygen as gas pulse. The characteristics of the ablated plasma are compared with those observed during pulsed laser deposition in different oxygen background pressures.

Effects of Handicap and Job Characteristics on Selection Evaluations.

ERIC Educational Resources Information Center

Rose, Gerald L.; Brief, Arthur P.

1979-01-01

Business administration students evaluated a hypothetical job applicant who was either an amputee, an epileptic, or "normal." The hypothetical job openings varied as to levels of supervisory responsibility and public contact. With some noted exceptions, the handicapped applicants were evaluated no differently than the normal applicants.…

Reactions to Hypothetical, Jealousy Producing Events.

ERIC Educational Resources Information Center

Hansen, Gary L.

1982-01-01

Asked subjects (N=220) how they would feel about their mates' behavior in eight hypothetical situations designed to measure jealousy. Responses indicated that jealousy is likely to be a major issue. Sex role orientation is most consistently related to jealousy with sex role traditional subjects being the most jealous. (Author)

Parents' Aggressive Influences and Children's Aggressive Problem Solutions with Peers

ERIC Educational Resources Information Center

Duman, Sarah; Margolin, Gayla

2007-01-01

This study examined children's aggressive and assertive solutions to hypothetical peer scenarios in relation to parents' responses to similar hypothetical social scenarios and parents' actual marital aggression. The study included 118 children ages 9 to 10 years old and their mothers and fathers. Children's aggressive solutions correlated with…

Risk Perception, Rape, and Sexual Revictimization: A Prospective Study of College Women

ERIC Educational Resources Information Center

Messman-Moore, Terri L.; Brown, Amy L.

2006-01-01

Risk perception was examined in relation to sexual victimization among 262 college women. Participants were presented with written vignettes that described hypothetical situations with a stranger and with an acquaintance. Participants' hypothetical decision to leave a potentially risky situation with an acquaintance predicted rape and…

Experiment and the Nature of Quantum Reality.

ERIC Educational Resources Information Center

Corwin, T. Mike; Wachowiak, Dale

1984-01-01

Although the Einstein-Podolsky-Rosen experiment was originally a hypothetical situation, John Bell was able to apply a version of their argument to an experiment that could actually be done. This experiment (called "Bell's Inequality") and a hypothetical experiment analogous to the one Bell proposed at the atomic level are described. (JN)

Learning Progressions and Teaching Sequences: A Review and Analysis

ERIC Educational Resources Information Center

Duschl, Richard; Maeng, Seungho; Sezen, Asli

2011-01-01

Our paper is an analytical review of the design, development and reporting of learning progressions and teaching sequences. Research questions are: (1) what criteria are being used to propose a "hypothetical learning progression/trajectory" and (2) what measurements/evidence are being used to empirically define and refine a "hypothetical learning…

Good and Evil at School: Bullying and Moral Evaluation in Early Adolescence

ERIC Educational Resources Information Center

Kollerová, Lenka; Janošová, Pavlína; Rícan, Pavel

2014-01-01

We investigated how adolescents (sixth-graders, N = 357) morally evaluated hypothetical bullying and defending protagonists and whether these evaluations related to behavior in bullying as nominated by peers. Exploratory factor analysis (EFA) resulted in four factors for the evaluation of the hypothetical bullies: "Evil soul,"…

47 CFR 69.607 - Disbursement of Carrier Common Line residue.

Code of Federal Regulations, 2011 CFR

2011-10-01

... shall bill that amount to such company. If such a company has a positive net balance, the association... Common Line residue by the sum of the hypothetical net balances for such companies. (c) The hypothetical..., Mar. 11, 1983, as amended at 51 FR 42237, Nov. 24, 1986] ...

47 CFR 69.607 - Disbursement of Carrier Common Line residue.

Code of Federal Regulations, 2012 CFR

2012-10-01

... shall bill that amount to such company. If such a company has a positive net balance, the association... Common Line residue by the sum of the hypothetical net balances for such companies. (c) The hypothetical..., Mar. 11, 1983, as amended at 51 FR 42237, Nov. 24, 1986] ...

47 CFR 69.607 - Disbursement of Carrier Common Line residue.

Code of Federal Regulations, 2014 CFR

2014-10-01

... shall bill that amount to such company. If such a company has a positive net balance, the association... Common Line residue by the sum of the hypothetical net balances for such companies. (c) The hypothetical..., Mar. 11, 1983, as amended at 51 FR 42237, Nov. 24, 1986] ...

47 CFR 69.607 - Disbursement of Carrier Common Line residue.

Code of Federal Regulations, 2013 CFR

2013-10-01

... shall bill that amount to such company. If such a company has a positive net balance, the association... Common Line residue by the sum of the hypothetical net balances for such companies. (c) The hypothetical..., Mar. 11, 1983, as amended at 51 FR 42237, Nov. 24, 1986] ...

47 CFR 69.607 - Disbursement of Carrier Common Line residue.

Code of Federal Regulations, 2010 CFR

2010-10-01

... shall bill that amount to such company. If such a company has a positive net balance, the association... Common Line residue by the sum of the hypothetical net balances for such companies. (c) The hypothetical..., Mar. 11, 1983, as amended at 51 FR 42237, Nov. 24, 1986] ...

The Mystery Tubes: Teaching Pupils about Hypothetical Modelling

ERIC Educational Resources Information Center

Kenrick, Carole

2017-01-01

This article recounts the author's working experience of one method by which pupils' understanding of the epistemologies of science can be developed, specifically how scientists can develop hypothetical models and test them through simulations. She currently uses this approach for transition lessons with pupils in upper primary or lower secondary…

Broad cross-reactive IgG responses elicited by adjuvanted vaccination with recombinant influenza hemagglutinin (rHA) in ferrets and mice

PubMed Central

Wang, Jiong; Hilchey, Shannon P.; DeDiego, Marta; Perry, Sheldon; Hyrien, Ollivier; Nogales, Aitor; Garigen, Jessica; Amanat, Fatima; Huertas, Nelson; Krammer, Florian; Martinez-Sobrido, Luis; Topham, David J.; Treanor, John J.; Sangster, Mark Y.

2018-01-01

Annual immunization against influenza virus is a large international public health effort. Accumulating evidence suggests that antibody mediated cross-reactive immunity against influenza hemagglutinin (HA) strongly correlates with long-lasting cross-protection against influenza virus strains that differ from the primary infection or vaccination strain. However, the optimal strategies for achieving highly cross-reactive antibodies to the influenza virus HA have not yet to be defined. In the current study, using Luminex-based mPlex-Flu assay, developed by our laboratory, to quantitatively measure influenza specific IgG antibody mediated cross-reactivity, we found that prime-boost-boost vaccination of ferrets with rHA proteins admixed with adjuvant elicited higher magnitude and broader cross-reactive antibody responses than that induced by actual influenza viral infection, and this cross-reactive response likely correlated with increased anti-stalk reactive antibodies. We observed a similar phenomenon in mice receiving three sequential vaccinations with rHA proteins from either A/California/07/2009 (H1N1) or A/Hong Kong/1/1968 (H3N2) viruses admixed with Addavax, an MF59-like adjuvant. Using this same mouse vaccination model, we determined that Addavax plays a more significant role in the initial priming event than in subsequent boosts. We also characterized the generation of cross-reactive antibody secreting cells (ASCs) and memory B cells (MBCs) when comparing vaccination to viral infection. We have also found that adjuvant plays a critical role in the generation of long-lived ASCs and MBCs cross-reactive to influenza viruses as a result of vaccination with rHA of influenza virus, and the observed increase in stalk-reactive antibodies likely contributes to this IgG mediated broad cross-reactivity. PMID:29641537

Broad cross-reactive IgG responses elicited by adjuvanted vaccination with recombinant influenza hemagglutinin (rHA) in ferrets and mice.

PubMed

Wang, Jiong; Hilchey, Shannon P; DeDiego, Marta; Perry, Sheldon; Hyrien, Ollivier; Nogales, Aitor; Garigen, Jessica; Amanat, Fatima; Huertas, Nelson; Krammer, Florian; Martinez-Sobrido, Luis; Topham, David J; Treanor, John J; Sangster, Mark Y; Zand, Martin S

2018-01-01

Annual immunization against influenza virus is a large international public health effort. Accumulating evidence suggests that antibody mediated cross-reactive immunity against influenza hemagglutinin (HA) strongly correlates with long-lasting cross-protection against influenza virus strains that differ from the primary infection or vaccination strain. However, the optimal strategies for achieving highly cross-reactive antibodies to the influenza virus HA have not yet to be defined. In the current study, using Luminex-based mPlex-Flu assay, developed by our laboratory, to quantitatively measure influenza specific IgG antibody mediated cross-reactivity, we found that prime-boost-boost vaccination of ferrets with rHA proteins admixed with adjuvant elicited higher magnitude and broader cross-reactive antibody responses than that induced by actual influenza viral infection, and this cross-reactive response likely correlated with increased anti-stalk reactive antibodies. We observed a similar phenomenon in mice receiving three sequential vaccinations with rHA proteins from either A/California/07/2009 (H1N1) or A/Hong Kong/1/1968 (H3N2) viruses admixed with Addavax, an MF59-like adjuvant. Using this same mouse vaccination model, we determined that Addavax plays a more significant role in the initial priming event than in subsequent boosts. We also characterized the generation of cross-reactive antibody secreting cells (ASCs) and memory B cells (MBCs) when comparing vaccination to viral infection. We have also found that adjuvant plays a critical role in the generation of long-lived ASCs and MBCs cross-reactive to influenza viruses as a result of vaccination with rHA of influenza virus, and the observed increase in stalk-reactive antibodies likely contributes to this IgG mediated broad cross-reactivity.

C-reactive protein levels and treatment resistance in schizophrenia-A Danish population-based cohort study.

PubMed

Horsdal, Henriette Thisted; Wimberley, Theresa; Benros, Michael Eriksen; Gasse, Christiane

2017-11-01

Schizophrenia is associated with increased levels of inflammatory markers. However, it remains unclear whether inflammatory markers are associated with treatment-resistant schizophrenia. We conducted a population-based follow-up study among individuals with a first-time schizophrenia diagnosis and a baseline C-reactive protein measurement (a commonly available marker of systemic inflammation) from 2000 to 2012. We defined treatment resistance as the earliest observed instance of either clozapine initiation or hospital admission due to schizophrenia after having received at least 2 prior antipsychotic monotherapy trials of adequate duration. We used adjusted Cox regression analysis to calculate hazard ratios. We identified 390 individuals with a C-reactive protein measurement at first-time schizophrenia diagnosis. A nonsignificant higher median C-reactive protein (4.0 vs. 3.1 mg/L, p = .13) was observed among the 52 (13.3%) treatment-resistant individuals. Increased levels of C-reactive protein (above 3 mg/L) at baseline were not associated with treatment resistance (adjusted hazard ratio = 0.99, 95% confidence interval [0.56, 1.73]). C-reactive protein, as a single inflammatory marker, appears insufficient to detect treatment-resistant schizophrenia. Copyright © 2017 John Wiley & Sons, Ltd.

Homogenous and heterogenous advanced oxidation of two commercial reactive dyes.

PubMed

Balcioglu, I A; Arslan, I; Sacan, M T

2001-07-01

Two commercial reactive dyes, the azo dye Reactive Black 5 and the copper phythalocyanine dye Reactive Blue 21, have been treated at a concentration of 75 mg l(-1) by titanium dioxide mediated photocatalytic (TiO2/UV), dark and UV-light assisted Fenton (Fe2+/H2O2) and Fenton-like (Fe3+/H2O2) processes in acidic medium. For the treatment of Reactive Black 5, all investigated advanced oxidation processes were quite effective in terms of colour, COD as well as TOC removal. Moreover, the relative growth inhibition of the azo dye towards the marine algae Dunaliella tertiolecta that was initially 70%, did not exhibit an increase during the studied advanced oxidation reactions and complete detoxification at the end of the treatment period could be achieved for all investigated treatment processes. However, for Reactive Blue 21, abatement in COD and UV-VIS absorbance values was mainly due to the adsorption of the dye on the photocatalyst surface and/or the coagulative effect of Fe3+/Fe2+ ions. Although only a limited fraction of the copper phythalocyanine dye underwent oxidative degradation, 47% of the total copper in the dye was already released after 1 h photocatalytic treatment.

Respiratory sinus arrhythmia reactivity to a sad film predicts depression symptom improvement and symptomatic trajectory

PubMed Central

Panaite, Vanessa; Hindash, Alexandra Cowden; Bylsma, Lauren M.; Small, Brent J.; Salomon, Kristen; Rottenberg, Jonathan

2015-01-01

Respiratory sinus arrhythmia (RSA) reactivity, an index of cardiac vagal tone, has been linked to self-regulation and the severity and course of depression (Rottenberg, 2007). Although initial data supports the proposition that RSA withdrawal during a sad film is a specific predictor of depression course (Fraguas, 2007; Rottenberg, 2005), the robustness and specificity of this finding are unclear. To provide a stronger test, RSA reactivity to three emotion films (happy, sad, fear) and to a more robust stressor, a speech task, were examined in currently depressed individuals (n = 37), who were assessed for their degree of symptomatic improvement over 30 weeks. Robust RSA reactivity to the sad film uniquely predicted overall symptom improvement over 30 weeks. RSA reactivity to both sad and stressful stimuli predicted the speed and maintenance of symptomatic improvement. The current analyses provide the most robust support to date that RSA withdrawal to sad stimuli (but not stressful) has specificity in predicting the overall symptomatic improvement. In contrast, RSA reactivity to negative stimuli (both sad and stressful) predicted the trajectory of depression course. Patients’ engagement with sad stimuli may be an important sign to attend to in therapeutic settings. PMID:26681648

Assessment of two-phase flow on the chemical alteration and sealing of leakage pathways in cemented wellbores

DOE PAGES

Iyer, Jaisree; Walsh, Stuart D. C.; Hao, Yue; ...

2018-01-08

Wellbore leakage tops the list of perceived risks to the long-term geologic storage of CO 2, because wells provide a direct path between the CO 2 storage reservoir and the atmosphere. In this paper, we have coupled a two-phase flow model with our original framework that combined models for reactive transport of carbonated brine, geochemistry of reacting cement, and geomechanics to predict the permeability evolution of cement fractures. Additionally, this makes the framework suitable for field conditions in geological storage sites, permitting simulation of contact between cement and mixtures of brine and supercritical CO 2. Due to lack of conclusivemore » experimental data, we tried both linear and Corey relative permeability models to simulate flow of the two phases in cement fractures. The model also includes two options to account for the inconsistent experimental observations regarding cement reactivity with two-phase CO 2-brine mixtures. One option assumes that the reactive surface area is independent of the brine saturation and the second option assumes that the reactive surface area is proportional to the brine saturation. We have applied the model to predict the extent of cement alteration, the conditions under which fractures seal, the time it takes to seal a fracture, and the leakage rates of CO 2 and brine when damage zones in the wellbore are exposed to two-phase CO 2-brine mixtures. Initial brine residence time and the initial fracture aperture are critical parameters that affect the fracture sealing behavior. We also evaluated the importance of the model assumptions regarding relative permeability and cement reactivity. These results illustrate the need to understand how mixtures of carbon dioxide and brine flow through fractures and react with cement to make reasonable predictions regarding well integrity. For example, a reduction in the cement reactivity with two-phase CO 2-brine mixture can not only significantly increase the sealing time for fractures but may also prevent fracture sealing.« less

SeSBench - An initiative to benchmark reactive transport models for environmental subsurface processes

NASA Astrophysics Data System (ADS)

Jacques, Diederik

2017-04-01

As soil functions are governed by a multitude of interacting hydrological, geochemical and biological processes, simulation tools coupling mathematical models for interacting processes are needed. Coupled reactive transport models are a typical example of such coupled tools mainly focusing on hydrological and geochemical coupling (see e.g. Steefel et al., 2015). Mathematical and numerical complexity for both the tool itself or of the specific conceptual model can increase rapidly. Therefore, numerical verification of such type of models is a prerequisite for guaranteeing reliability and confidence and qualifying simulation tools and approaches for any further model application. In 2011, a first SeSBench -Subsurface Environmental Simulation Benchmarking- workshop was held in Berkeley (USA) followed by four other ones. The objective is to benchmark subsurface environmental simulation models and methods with a current focus on reactive transport processes. The final outcome was a special issue in Computational Geosciences (2015, issue 3 - Reactive transport benchmarks for subsurface environmental simulation) with a collection of 11 benchmarks. Benchmarks, proposed by the participants of the workshops, should be relevant for environmental or geo-engineering applications; the latter were mostly related to radioactive waste disposal issues - excluding benchmarks defined for pure mathematical reasons. Another important feature is the tiered approach within a benchmark with the definition of a single principle problem and different sub problems. The latter typically benchmarked individual or simplified processes (e.g. inert solute transport, simplified geochemical conceptual model) or geometries (e.g. batch or one-dimensional, homogeneous). Finally, three codes should be involved into a benchmark. The SeSBench initiative contributes to confidence building for applying reactive transport codes. Furthermore, it illustrates the use of those type of models for different environmental and geo-engineering applications. SeSBench will organize new workshops to add new benchmarks in a new special issue. Steefel, C. I., et al. (2015). "Reactive transport codes for subsurface environmental simulation." Computational Geosciences 19: 445-478.

Assessment of two-phase flow on the chemical alteration and sealing of leakage pathways in cemented wellbores

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

Iyer, Jaisree; Walsh, Stuart D. C.; Hao, Yue

Wellbore leakage tops the list of perceived risks to the long-term geologic storage of CO 2, because wells provide a direct path between the CO 2 storage reservoir and the atmosphere. In this paper, we have coupled a two-phase flow model with our original framework that combined models for reactive transport of carbonated brine, geochemistry of reacting cement, and geomechanics to predict the permeability evolution of cement fractures. Additionally, this makes the framework suitable for field conditions in geological storage sites, permitting simulation of contact between cement and mixtures of brine and supercritical CO 2. Due to lack of conclusivemore » experimental data, we tried both linear and Corey relative permeability models to simulate flow of the two phases in cement fractures. The model also includes two options to account for the inconsistent experimental observations regarding cement reactivity with two-phase CO 2-brine mixtures. One option assumes that the reactive surface area is independent of the brine saturation and the second option assumes that the reactive surface area is proportional to the brine saturation. We have applied the model to predict the extent of cement alteration, the conditions under which fractures seal, the time it takes to seal a fracture, and the leakage rates of CO 2 and brine when damage zones in the wellbore are exposed to two-phase CO 2-brine mixtures. Initial brine residence time and the initial fracture aperture are critical parameters that affect the fracture sealing behavior. We also evaluated the importance of the model assumptions regarding relative permeability and cement reactivity. These results illustrate the need to understand how mixtures of carbon dioxide and brine flow through fractures and react with cement to make reasonable predictions regarding well integrity. For example, a reduction in the cement reactivity with two-phase CO 2-brine mixture can not only significantly increase the sealing time for fractures but may also prevent fracture sealing.« less

Matrix photochemistry of small molecules: Influencing reaction dynamics on electronically excited hypersurfaces

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

Laursen, S.L.

Investigations of chemical reactions on electronically excited reaction surfaces are presented. The role of excited-surface multiplicity is of particular interest, as are chemical reactivity and energy transfer in systems in which photochemistry is initiated through a metal atom sensitizer.'' Two approaches are employed: A heavy-atom matrix affords access to forbidden triplet reaction surfaces, eliminating the need for a potentially reactive sensitizer. Later, the role of the metal atom in the photosensitization process is examined directly.

Understanding Latent Tuberculosis: A Moving Target

PubMed Central

Lin, Philana Ling; Flynn, JoAnne L.

2012-01-01

Tuberculosis (TB) remains a threat to the health of people worldwide. Infection with Mycobacterium tuberculosis can result in active TB or, more commonly, latent infection. Latently infected persons, of which there are estimated to be ~2 billion in the world, represent an enormous reservoir of potential reactivation TB, which can spread to other people. The immunology of TB is complex and multifaceted. Identifying the immune mechanisms that lead to control of initial infection and prevent reactivation of latent infection is crucial to combating this disease. PMID:20562268

Photoredox Catalysis Unlocks Single-Electron Elementary Steps in Transition Metal Catalyzed Cross-Coupling

PubMed Central

2016-01-01

Since initial reports, cross-coupling technologies employing photoredox catalysts to access novel reactivity have developed with increasing pace. In this Outlook, prominent examples from the recent literature are organized on the basis of the elementary transformation enabled by photoredox catalysis and are discussed in the context of relevant historical precedent in stoichiometric organometallic chemistry. This treatment allows mechanistic similarities inherent to odd-electron transition metal reactivity to be generalized to a set of lessons for future reaction development. PMID:27280163

Green oxidations of furans--initiated by molecular oxygen--that give key natural product motifs.

PubMed

Montagnon, Tamsyn; Noutsias, Dimitris; Alexopoulou, Ioanna; Tofi, Maria; Vassilikogiannakis, Georgios

2011-04-07

In this article, we explore how changes in the positioning of pendant hydroxyl functionalities in the photooxygenation substrate dramatically alter the course of furan oxidations that are initiated by singlet oxygen; and, how these different reactivities can be harnessed through cascade reaction sequences to access, rapidly and effectively, a broad range of important natural product motifs.

Development of a Fragment-Based in Silico Profiler for Michael Addition Thiol Reactivity.

PubMed

Ebbrell, David J; Madden, Judith C; Cronin, Mark T D; Schultz, Terry W; Enoch, Steven J

2016-06-20

The Adverse Outcome Pathway (AOP) paradigm details the existing knowledge that links the initial interaction between a chemical and a biological system, termed the molecular initiating event (MIE), through a series of intermediate events, to an adverse effect. An important example of a well-defined MIE is the formation of a covalent bond between a biological nucleophile and an electrophilic compound. This particular MIE has been associated with various toxicological end points such as acute aquatic toxicity, skin sensitization, and respiratory sensitization. This study has investigated the calculated parameters that are required to predict the rate of chemical bond formation (reactivity) of a dataset of Michael acceptors. Reactivity of these compounds toward glutathione was predicted using a combination of a calculated activation energy value (Eact, calculated using density functional theory (DFT) calculation at the B3YLP/6-31G+(d) level of theory, and solvent-accessible surface area values (SAS) at the α carbon. To further develop the method, a fragment-based algorithm was developed enabling the reactivity to be predicted for Michael acceptors without the need to perform the time-consuming DFT calculations. Results showed the developed fragment method was successful in predicting the reactivity of the Michael acceptors excluding two sets of chemicals: volatile esters with an extended substituent at the β-carbon and chemicals containing a conjugated benzene ring as part of the polarizing group. Additionally the study also demonstrated the ease with which the approach can be extended to other chemical classes by the calculation of additional fragments and their associated Eact and SAS values. The resulting method is likely to be of use in regulatory toxicology tools where an understanding of covalent bond formation as a potential MIE is important within the AOP paradigm.

Theory and simulation of the time-dependent rate coefficients of diffusion-influenced reactions.

PubMed Central

Zhou, H X; Szabo, A

1996-01-01

A general formalism is developed for calculating the time-dependent rate coefficient k(t) of an irreversible diffusion-influenced reaction. This formalism allows one to treat most factors that affect k(t), including rotational Brownian motion and conformational gating of reactant molecules and orientation constraint for product formation. At long times k(t) is shown to have the asymptotic expansion k(infinity)[1 + k(infinity) (pie Dt)-1/2 /4 pie D + ...], where D is the relative translational diffusion constant. An approximate analytical method for calculating k(t) is presented. This is based on the approximation that the probability density of the reactant pair in the reactive region keeps the equilibrium distribution but with a decreasing amplitude. The rate coefficient then is determined by the Green function in the absence of chemical reaction. Within the framework of this approximation, two general relations are obtained. The first relation allows the rate coefficient for an arbitrary amplitude of the reactivity to be found if the rate coefficient for one amplitude of the reactivity is known. The second relation allows the rate coefficient in the presence of conformational gating to be found from that in the absence of conformational gating. The ratio k(t)/k(0) is shown to be the survival probability of the reactant pair at time t starting from an initial distribution that is localized in the reactive region. This relation forms the basis of the calculation of k(t) through Brownian dynamics simulations. Two simulation procedures involving the propagation of nonreactive trajectories initiated only from the reactive region are described and illustrated on a model system. Both analytical and simulation results demonstrate the accuracy of the equilibrium-distribution approximation method. PMID:8913584

Soil processes and functions across an international network of Critical Zone Observatories: Introduction to experimental methods and initial results

NASA Astrophysics Data System (ADS)

Banwart, Steven; Menon, Manoj; Bernasconi, Stefano M.; Bloem, Jaap; Blum, Winfried E. H.; Souza, Danielle Maia de; Davidsdotir, Brynhildur; Duffy, Christopher; Lair, Georg J.; Kram, Pavel; Lamacova, Anna; Lundin, Lars; Nikolaidis, Nikolaos P.; Novak, Martin; Panagos, Panos; Ragnarsdottir, Kristin Vala; Reynolds, Brian; Robinson, David; Rousseva, Svetla; de Ruiter, Peter; van Gaans, Pauline; Weng, Liping; White, Tim; Zhang, Bin

2012-11-01

Growth in human population and demand for wealth creates ever-increasing pressure on global soils, leading to soil losses and degradation worldwide. Critical Zone science studies the impact linkages between these pressures, the resulting environmental state of soils, and potential interventions to protect soil and reverse degradation. New research on soil processes is being driven by the scientific hypothesis that soil processes can be described along a life cycle of soil development. This begins with formation of new soil from parent material, development of the soil profile, and potential loss of the developed soil functions and the soil itself under overly intensive anthropogenic land use, thus closing the cycle. Four Critical Zone Observatories in Europe have been selected focusing research at sites that represent key stages along the hypothetical soil life cycle; incipient soil formation, productive use of soil for farming and forestry, and decline of soil due to longstanding intensive agriculture. Initial results from the research show that soil develops important biogeochemical properties on the time scale of decades and that soil carbon and the development of favourable soil structure takes place over similar time scales. A new mathematical model of soil aggregate formation and degradation predicts that set-aside land at the most degraded site studied can develop substantially improved soil structure with the accumulation of soil carbon over a period of several years. Further results demonstrate the rapid dynamics of soil carbon; how quickly it can be lost, and also demonstrate how data from the CZOs can be used to determine parameter values for models at catchment scale. A structure for a new integrated Critical Zone model is proposed that combines process descriptions of carbon and nutrient flows, a simplified description of the soil food web, and reactive transport; all coupled with a dynamic model for soil structure and soil aggregation. This approach is proposed as a methodology to analyse data along the soil life cycle and test how soil processes and rates vary within, and between, the CZOs representing different life cycle stages. In addition, frameworks are discussed that will help to communicate the results of this science into a more policy relevant format using ecosystem service approaches.

Piwil2 is reactivated by HPV oncoproteins and initiates cell reprogramming via epigenetic regulation during cervical cancer tumorigenesis.

PubMed

Feng, Dingqing; Yan, Keqin; Zhou, Ying; Liang, Haiyan; Liang, Jing; Zhao, Weidong; Dong, Zhongjun; Ling, Bin

2016-10-04

The human papillomavirus (HPV) oncoproteins E6 and E7 are risk factors that are primarily responsible for the initiation and progression of cervical cancer, and they play a key role in immortalization and transformation by reprogramming differentiating host epithelial cells. It is unclear how cervical epithelial cells transform into tumor-initiating cells (TICs). Here, we observed that the germ stem cell protein Piwil2 is expressed in pre-cancerous and malignant lesions of the cervix and cervical cancer cell lines with the exception of the non-HPV-infected C33a cell line. Knockdown of Piwil2 by shRNA led to a marked reduction in proliferation and colony formation, in vivo tumorigenicity, chemo-resistance, and the proportion of cancer stem-like cells. In contrast, Piwil2 overexpression induced malignant transformation of HaCaT cells and the acquisition of tumor-initiating capabilities. Gene-set enrichment analysis revealed embryonic stem cell (ESC) identity, malignant biological behavior, and specifically, activation targets of the cell reprogramming factors c-Myc, Klf4, Nanog, Oct4, and Sox2 in Piwil2-overexpressing HaCaT cells. We further confirmed that E6 and E7 reactivated Piwil2 and that E6 and E7 overexpression resulted in a similar gene-set enrichment pattern as Piwil2 overexpression in HaCaT cells. Moreover, Piwil2 overexpression or E6 and E7 activation induced H3K9 acetylation but reduced H3K9 trimethylation, which contributed to the epigenetic reprogramming and ESC signature maintenance, as predicted previously. Our study demonstrates that Piwil2, reactivated by the HPV oncoproteins E6 and E7, plays an essential role in the transformation of cervical epithelial cells to TICs via epigenetics-based cell reprogramming.

Incidence of Latent Virus Shedding during Space Flight

NASA Technical Reports Server (NTRS)

Mehta, Satish K.; Cohrs, Randall J.; Gilden, Donald H.; Tyring, Stephen K.; Ott, C. Mark; Pierson, Duane L.

2008-01-01

Measurements of immune parameters of both cellular and innate immunity indicate alterations in immune function in astronauts. Immune changes are due to stress and perhaps other factors associated with launch, flight, and landing phases. Medical relevance of observed changes is not known. The reactivation of latent viruses has been identified as an important in vivo indicator of clinically relevant immune changes. The polymerase chain reaction (PCR) was used to detect the presence of specific viral DNA in body fluids. Initial studies demonstrated Epstein-Barr virus (EBV) reactivation during all 3 mission phases. EBV is shed in saliva following reactivation from B-cells. Incidence of EBV in saliva was higher than control subjects during all 3 mission phases. However, quantitative PCR revealed 10-fold higher levels of EBV DNA present in saliva collected during flight than found in pre- and post flight specimens. To determine if other latent viruses showed similar effects, cytomegalovirus (CMV), another herpes virus, shed in urine following reactivation was studied. A very low incidence (less than 2%) of CMV in urine is found in healthy, lowstressed individuals. However, 25-50% of astronauts shed CMV in their urine before, during, or after flight. Our studies are now focused on varicella-zoster virus (VZV), the etiological agent of chicken-pox during childhood and shingles later in life. We demonstrated reactivation of VZV and shedding of the virus during and after spaceflight in saliva of astronauts with no sign of active infection or symptoms. The maximum shedding of VZV occurred during the flight phase and diminishes rapidly during the first five days after landing. We have utilized the same PCR assay for VZV in a clinical study of shingles patients. Generally, shingles patients shed much more VZV in saliva than astronauts. However, the VZV levels in astronauts overlap with the lower range of VZV numbers in shingles patients. Saliva from shingles patients and astronauts were cultured and infectious VZV was recovered from both groups. We have concluded that multiple latent viruses do reactivate before, during, and after spaceflight and serve as very sensitive indicators for diminished cellular immunity. Future plans will be focused on the clinical risks posed by the reactivation of these viruses. Initial efforts will determine the effect of longer missions on the International Space Station on the reactivation patterns of these viruses.

Deformation dependence of proton decay rates and angular distributions in a time-dependent approach

NASA Astrophysics Data System (ADS)

Carjan, N.; Talou, P.; Strottman, D.

1998-12-01

A new, time-dependent, approach to proton decay from axially symmetric deformed nuclei is presented. The two-dimensional time-dependent Schrödinger equation for the interaction between the emitted proton and the rest of the nucleus is solved numerically for well defined initial quasi-stationary proton states. Applied to the hypothetical proton emission from excited states in deformed nuclei of 208Pb, this approach shows that the problem cannot be reduced to one dimension. There are in general more than one directions of emission with wide distributions around them, determined mainly by the quantum numbers of the initial wave function rather than by the potential landscape. The distribution of the "residual" angular momentum and its variation in time play a major role in the determination of the decay rate. In a couple of cases, no exponential decay was found during the calculated time evolution (2×10-21 sec) although more than half of the wave function escaped during that time.

Preferences for the Return of Individual Results From Research on Pediatric Biobank Samples.

PubMed

Christensen, Kurt D; Savage, Sarah K; Huntington, Noelle L; Weitzman, Elissa R; Ziniel, Sonja I; Bacon, Phoebe L; Cacioppo, Cara N; Green, Robert C; Holm, Ingrid A

2017-04-01

Discussions about disclosing individual genetic research results include calls to consider participants' preferences. In this study, parents of Boston Children's Hospital patients set preferences for disclosure based on disease preventability and severity, and could exclude mental health, developmental, childhood degenerative, and adult-onset disorders. Participants reviewed hypothetical reports and reset preferences, if desired. Among 661 participants who initially wanted all results (64%), 1% reset preferences. Among 336 participants who initially excluded at least one category (36%), 38% reset preferences. Participants who reset preferences added 0.9 categories, on average; and their mean satisfaction on 0 to 10 scales increased from 4.7 to 7.2 ( p < .001). Only 2% reduced the number of categories they wanted disclosed. Findings demonstrate the benefits of providing examples of preference options and the tendency of participants to want results disclosed. Findings also suggest that preference-setting models that do not provide specific examples of results could underestimate participants' desires for information.

Preferences for the return of individual results from research on pediatric biobank samples

PubMed Central

Christensen, Kurt D.; Savage, Sarah K.; Huntington, Noelle L.; Weitzman, Elissa R.; Ziniel, Sonja I.; Bacon, Phoebe L.; Cacioppo, Cara N.; Green, Robert C.; Holm, Ingrid A.

2016-01-01

Discussions about disclosing individual genetic research results include calls to consider participants’ preferences. In this study, parents of Boston Children’s Hospital patients set preferences for disclosure based on disease preventability and severity, and could exclude mental health, developmental, childhood degenerative, and adult-onset disorders. Participants reviewed hypothetical reports and reset preferences, if desired. Among 661 participants who initially wanted all results (64%), 1% reset preferences. Among 336 participants who initially excluded at least one category (36%), 38% reset preferences. Participants who reset preferences added 0.9 categories, on average; and their mean satisfaction on 0–10 scales increased from 4.7 to 7.2 (p<0.001). Only 2% reduced the number of categories they wanted disclosed. Findings demonstrate the benefits of providing examples of preference options and the tendency of participants to want results disclosed. Findings also suggest that preference-setting models that do not provide specific examples of results could underestimate participants’ desires for information. PMID:28421887

Work fluctuations for Bose particles in grand canonical initial states.

PubMed

Yi, Juyeon; Kim, Yong Woon; Talkner, Peter

2012-05-01

We consider bosons in a harmonic trap and investigate the fluctuations of the work performed by an adiabatic change of the trap curvature. Depending on the reservoir conditions such as temperature and chemical potential that provide the initial equilibrium state, the exponentiated work average (EWA) defined in the context of the Crooks relation and the Jarzynski equality may diverge if the trap becomes wider. We investigate how the probability distribution function (PDF) of the work signals this divergence. It is shown that at low temperatures the PDF is highly asymmetric with a steep fall-off at one side and an exponential tail at the other side. For high temperatures it is closer to a symmetric distribution approaching a Gaussian form. These properties of the work PDF are discussed in relation to the convergence of the EWA and to the existence of the hypothetical equilibrium state to which those thermodynamic potential changes refer that enter both the Crooks relation and the Jarzynski equality.

Numerical optimization of Ignition and Growth reactive flow modeling for PAX2A

NASA Astrophysics Data System (ADS)

Baker, E. L.; Schimel, B.; Grantham, W. J.

1996-05-01

Variable metric nonlinear optimization has been successfully applied to the parameterization of unreacted and reacted products thermodynamic equations of state and reactive flow modeling of the HMX based high explosive PAX2A. The NLQPEB nonlinear optimization program has been recently coupled to the LLNL developed two-dimensional high rate continuum modeling programs DYNA2D and CALE. The resulting program has the ability to optimize initial modeling parameters. This new optimization capability was used to optimally parameterize the Ignition and Growth reactive flow model to experimental manganin gauge records. The optimization varied the Ignition and Growth reaction rate model parameters in order to minimize the difference between the calculated pressure histories and the experimental pressure histories.

Surface Modified Particles By Multi-Step Michael-Type Addition And Process For The Preparation Thereof

DOEpatents

Cook, Ronald Lee; Elliott, Brian John; Luebben, Silvia DeVito; Myers, Andrew William; Smith, Bryan Matthew

2005-05-03

A new class of surface modified particles and a multi-step Michael-type addition surface modification process for the preparation of the same is provided. The multi-step Michael-type addition surface modification process involves two or more reactions to compatibilize particles with various host systems and/or to provide the particles with particular chemical reactivities. The initial step comprises the attachment of a small organic compound to the surface of the inorganic particle. The subsequent steps attach additional compounds to the previously attached organic compounds through reactive organic linking groups. Specifically, these reactive groups are activated carbon—carbon pi bonds and carbon and non-carbon nucleophiles that react via Michael or Michael-type additions.

NUCLEAR REACTOR CONTROL SYSTEM

DOEpatents

Howard, D.F.; Motta, E.E.

1961-06-27

A method for controlling the excess reactivity in a nuclear reactor throughout the core life while maintaining the neutron flux distribution at the desired level is described. The control unit embodies a container having two electrodes of different surface area immersed in an electrolytic solution of a good neutron sbsorbing metal ion such as boron, gadolinium, or cadmium. Initially, the neutron absorber is plated on the larger electrode to control the greater neutron flux of a freshly refueled core. As the fuel burns up, the excess reactivity decreases and the neutron absorber is then plated onto the smaller electrode so that the number of neutrons absorbed also decreases. The excess reactivity in the core may thus be maintained without the introduction of serious perturbations in the neutron flux distributibn.

Steep, cheap and deep: an ideotype to optimize water and N acquisition by maize root systems.

PubMed

Lynch, Jonathan P

2013-07-01

A hypothetical ideotype is presented to optimize water and N acquisition by maize root systems. The overall premise is that soil resource acquisition is optimized by the coincidence of root foraging and resource availability in time and space. Since water and nitrate enter deeper soil strata over time and are initially depleted in surface soil strata, root systems with rapid exploitation of deep soil would optimize water and N capture in most maize production environments. • THE IDEOTYPE: Specific phenes that may contribute to rooting depth in maize include (a) a large diameter primary root with few but long laterals and tolerance of cold soil temperatures, (b) many seminal roots with shallow growth angles, small diameter, many laterals, and long root hairs, or as an alternative, an intermediate number of seminal roots with steep growth angles, large diameter, and few laterals coupled with abundant lateral branching of the initial crown roots, (c) an intermediate number of crown roots with steep growth angles, and few but long laterals, (d) one whorl of brace roots of high occupancy, having a growth angle that is slightly shallower than the growth angle for crown roots, with few but long laterals, (e) low cortical respiratory burden created by abundant cortical aerenchyma, large cortical cell size, an optimal number of cells per cortical file, and accelerated cortical senescence, (f) unresponsiveness of lateral branching to localized resource availability, and (g) low K(m) and high Vmax for nitrate uptake. Some elements of this ideotype have experimental support, others are hypothetical. Despite differences in N distribution between low-input and commercial maize production, this ideotype is applicable to low-input systems because of the importance of deep rooting for water acquisition. Many features of this ideotype are relevant to other cereal root systems and more generally to root systems of dicotyledonous crops.

A comparison of approaches to mitigate hypothetical bias

Treesearch

Patricia A. Champ; Rebecca Moore; Richard C. Bishop

2009-01-01

We compare two approaches to mitigating hypothetical bias. The study design includes three treatments: an actual payment treatment, a contingent valuation (CV) treatment with a followup certainty question, and a CV treatment with a cheap talk script. Our results suggest that both the follow-up certainty treatment and the cheap talk treatment produce...

When Can We Say "If"?

ERIC Educational Resources Information Center

Evans, Jonathan St. B. T.; Neilens, Helen; Handley, Simon J.; Over, David E.

2008-01-01

In this study, we focus on the conditions which permit people to assert a conditional statement of the form "if p then q" with conversational relevance. In a broadly decision-theoretic approach, also drawing on hypothetical thinking theory [Evans, J. St. B. T. (2007). "Hypothetical thinking: Dual processes in reasoning and judgement". Hove, UK:…

Reasoning about Make-Believe and Hypothetical Suppositions: Towards a Theory of Belief-Contravening Reasoning

ERIC Educational Resources Information Center

Amsel, Eric; Trionfi, Gabriel; Campbell, Richard

2005-01-01

The present study explores how suppositions which conflict with accepted beliefs are represented and reasoned about. Two studies test the predictions regarding the nature and developmental changes in children's ability to represent and reason about hypothetical or make-believe suppositions which violate their everyday knowledge and beliefs. In…

Hypothetical Insurance and Higher Education

ERIC Educational Resources Information Center

Colburn, Ben; Lazenby, Hugh

2016-01-01

What level of government subsidy of higher education is justified, in what form, and for what reasons? We answer these questions by applying the hypothetical insurance approach, originally developed by Ronald Dworkin in his work on distributive justice. On this approach, when asking how to fund and deliver public services in a particular domain,…

75 FR 57063 - Distribution of the 2004 and 2005 Cable Royalty Funds

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-17

... right to retransmit such programming is not determined in a free market, but rather is determined... would be valued in a hypothetical free market that would exist but for the regulatory regime currently in place. However, such a hypothetical free market value for non-network distant signal programming...

Hypothetical: The Case for an Australian "Group of Seven"

ERIC Educational Resources Information Center

Turner, Michael; Brown, Alistair

2013-01-01

This paper examines the hypothetical cost-savings that might ensue from a merger of most of Australia's major research universities. The results of the textual analysis show that a merger of these universities has the potential to reduce expenses and professional and support staff salaries, increase comprehensive income returns and improve…

Children's Thinking about Counterfactuals and Future Hypotheticals as Possibilities

ERIC Educational Resources Information Center

Beck, Sarah R.; Robinson, Elizabeth J.; Carroll, Daniel J.; Apperly, Ian A.

2006-01-01

Two experiments explored whether children's correct answers to counter factual and future hypothetical questions were based on an understanding of possibilities. Children played a game in which a toy mouse could run down either 1 of 2 slides. Children found it difficult to mark physically both possible outcomes, compared to reporting a single…

Improving the Past and the Future: A Temporal Asymmetry in Hypothetical Thinking

ERIC Educational Resources Information Center

Ferrante, Donatella; Girotto, Vittorio; Straga, Marta; Walsh, Clare

2013-01-01

Current views of hypothetical thinking implicitly assume that the content of imaginary thoughts about the past and future should be the same. Two experiments show that, given the same experienced facts of reality, future imagination may differ from past reconstruction. When participants failed a task, their counterfactual thoughts focused on…

Substance Abuse Counselors and Moral Reasoning: Hypothetical and Authentic Dilemmas

ERIC Educational Resources Information Center

Sias, Shari M.

2009-01-01

This exploratory study examined the assumption that the level of moral reasoning (Defining Issues Test; J. R. Rest, 1986) used in solving hypothetical and authentic dilemmas is similar for substance abuse counselors (N = 188). The statistical analyses used were paired-sample t tests, Pearson product-moment correlation, and simultaneous multiple…

33 CFR Appendix B to Part 277 - Hypothetical Example of Cost Apportionment

Code of Federal Regulations, 2013 CFR

2013-07-01

...) $165,489 I b. Fixed charges (owner's share) 284,460 II A fixed charge such as engineering, design and... new bridge is designed for increased loading and width greater than that of the old bridge. Therefore, the estimated annual maintenance cost was based on a hypothetical bridge designed, but not constructed...

33 CFR Appendix B to Part 277 - Hypothetical Example of Cost Apportionment

Code of Federal Regulations, 2014 CFR

2014-07-01

...) $165,489 I b. Fixed charges (owner's share) 284,460 II A fixed charge such as engineering, design and... new bridge is designed for increased loading and width greater than that of the old bridge. Therefore, the estimated annual maintenance cost was based on a hypothetical bridge designed, but not constructed...

33 CFR Appendix B to Part 277 - Hypothetical Example of Cost Apportionment

Code of Federal Regulations, 2010 CFR

2010-07-01

...) $165,489 I b. Fixed charges (owner's share) 284,460 II A fixed charge such as engineering, design and... new bridge is designed for increased loading and width greater than that of the old bridge. Therefore, the estimated annual maintenance cost was based on a hypothetical bridge designed, but not constructed...

33 CFR Appendix B to Part 277 - Hypothetical Example of Cost Apportionment

Code of Federal Regulations, 2011 CFR

2011-07-01

...) $165,489 I b. Fixed charges (owner's share) 284,460 II A fixed charge such as engineering, design and... new bridge is designed for increased loading and width greater than that of the old bridge. Therefore, the estimated annual maintenance cost was based on a hypothetical bridge designed, but not constructed...

33 CFR Appendix B to Part 277 - Hypothetical Example of Cost Apportionment

Code of Federal Regulations, 2012 CFR

2012-07-01

...) $165,489 I b. Fixed charges (owner's share) 284,460 II A fixed charge such as engineering, design and... new bridge is designed for increased loading and width greater than that of the old bridge. Therefore, the estimated annual maintenance cost was based on a hypothetical bridge designed, but not constructed...

Investigation of Advanced Personnel Armor Using Layered Construction

DTIC Science & Technology

2009-12-01

foam were constructed to test against baseline armor AISI 4140 steel plate. A hypothetical orthotropic material model closely resembling that of...against baseline armor AISI 4140 steel plate. A hypothetical orthotropic material model closely resembling that of Dyneema HB25 was derived based on...54 2. Steel AISI 4140 ...................................................................................56 3. Composite Plates

Developing Self-Regulated Learners through Collaborative Online Case Discussion in Educational Psychology

ERIC Educational Resources Information Center

Willems, Patricia P.; Gonzalez-DeHass, Alyssa

2015-01-01

Case study instruction is characterized by centering instruction around the use of hypothetical classroom dilemmas. It uses descriptive stories and invites students to discuss application of course material as they engage in hypothetical classroom problem-solving and teacher decision-making. Teaching is a complex profession that requires high…

Perceptions of, and Assistance Provided to, a Hypothetical Rape Victim: Differences between Rape Disclosure Recipients and Nonrecipients

ERIC Educational Resources Information Center

Paul, Lisa A.; Kehn, Andre; Gray, Matt J.; Salapska-Gelleri, Joanna

2014-01-01

Objective: Undergraduate rape disclosure recipients' and nonrecipients' sociodemographic and life experience variables, attitudes towards rape, and responses to a hypothetical rape disclosure were compared to determine differences between them. Participants: One hundred ninety-two undergraduates at 3 universities participated in this online survey…

The Influence of Gender in the Selection of Secondary School Principals.

ERIC Educational Resources Information Center

Bonuso, Carl; Shakeshaft, Charol

A sample of 472 superintendents in New York State participated in this study, which examined the presence of sex discrimination in the selection of secondary school principals. The superintendents were asked to rate a hypothetical applicant resume that included credentials and a photograph. A hypothetical job description of a secondary school…

Cesium Neonide: Molecule or Thermochemical Exercise?

ERIC Educational Resources Information Center

Blake, P. G.; Clack, D. W.

1982-01-01

Thermochemical cycles are used to decide which hypothetical compounds might exist and, if not, what is the factor that condemns them to non-existence. Hypothetical compounds of rare gases provide examples of the approach with added historical interest that thermochemical considerations led to prediction and demonstration that XePtF-6 was stable.…

Person x Context Effects on Anticipated Moral Emotions Following Aggression

ERIC Educational Resources Information Center

Roos, Sanna; Salmivalli, Christina; Hodges, Ernest V. E.

2011-01-01

We investigated person (sex, aggression level), context (witness type, victim reactions), and person x context effects on children's anticipated moral emotions following hypothetical acts of aggression against a peer. Children (N = 378, mean age = 11.3 years) were presented a series of hypothetical vignettes in which the presence of witnesses (no…

A Hypothetical Learning Trajectory for Conceptualizing Matrices as Linear Transformations

ERIC Educational Resources Information Center

Andrews-Larson, Christine; Wawro, Megan; Zandieh, Michelle

2017-01-01

In this paper, we present a hypothetical learning trajectory (HLT) aimed at supporting students in developing flexible ways of reasoning about matrices as linear transformations in the context of introductory linear algebra. In our HLT, we highlight the integral role of the instructor in this development. Our HLT is based on the "Italicizing…

Children's Use and Knowledge of Display Rules for Anger following Hypothetical Vignettes versus following Live Peer Interaction.

ERIC Educational Resources Information Center

Parker, Elizabeth H.; Hubbard, Julie A.; Ramsden, Sally R.; Relyea, Nicole; Dearing, Karen F.; Smithmyer, Catherine M.; Schimmel, Kelly D.

2001-01-01

Examined correspondence between second-graders' use and knowledge of anger display rules. Found that children's responses were moderately related across two contexts. Following live interactions, compared to hypothetical vignettes, children reported feeling and expressing less anger, intending to hide their anger more, and dissembling their anger…

Transcription precedes loss of Xist coating and depletion of H3K27me3 during X-chromosome reprogramming in the mouse inner cell mass

PubMed Central

Williams, Lucy H.; Kalantry, Sundeep; Starmer, Joshua; Magnuson, Terry

2011-01-01

Repression of Xist RNA expression is considered a prerequisite to reversal of X-chromosome inactivation (XCI) in the mouse inner cell mass (ICM), and reactivation of X-linked genes is thought to follow loss of Xist RNA coating and heterochromatic markers of inactivation, such as methylation of histone H3. We analyzed X-chromosome activity in developing ICMs and show that reactivation of gene expression from the inactive-X initiates in the presence of Xist coating and H3K27me3. Furthermore, depletion of Xist RNA coating through forced upregulation of NANOG does not result in altered reactivation kinetics. Taken together, our observations suggest that in the ICM, X-linked gene transcription and Xist coating are uncoupled. These data fundamentally alter our perception of the reactivation process and support the existence of a mechanism to reactivate Xp-linked genes in the ICM that operates independently of loss of Xist RNA and H3K27me3 from the imprinted inactive-X. PMID:21471155

Shock Initiated Reactions of Reactive Multiphase Blast Explosives

NASA Astrophysics Data System (ADS)

Wilson, Dennis; Granier, John; Johnson, Richard; Littrell, Donald

2015-06-01

This paper describes a new class of reactive multiphase blast explosives (RMBX) and characterization of their blast characteristics. These RMBXs are non-ideal explosive compositions of perfluoropolyether (PFPE), nano aluminum, and a micron-size high-density reactive metal - Tantalum, Zirconium, or Zinc in mass loadings of 66 to 83 percent. Unlike high explosives, these PFPE-metal compositions release energy via a fast self-oxidized combustion wave (rather than a true self-sustaining detonation) that is shock dependent, and can be overdriven to control energy release rate. The term ``reactive multiphase blast'' refers to the post-dispersion blast behavior: multiphase in that there are a gas phase that imparts pressure and a solid (particulate) phase that imparts momentum; and reactive in that the hot metal particles react with atmospheric oxygen and the explosive gas products to give an extended pressure pulse. The RMBX formulations were tested in two spherical core-shell geometries - an RMBX shell exploded by a high explosive core, and an RMBX core imploded by a high explosive shell. The fireball and blast characteristics were compared to a C-4 baseline charge.

Impedance measurement of non-locally reactive samples and the influence of the assumption of local reaction.

PubMed

Brandão, Eric; Mareze, Paulo; Lenzi, Arcanjo; da Silva, Andrey R

2013-05-01

In this paper, the measurement of the absorption coefficient of non-locally reactive sample layers of thickness d1 backed by a rigid wall is investigated. The investigation is carried out with the aid of real and theoretical experiments, which assume a monopole sound source radiating sound above an infinite non-locally reactive layer. A literature search revealed that the number of papers devoted to this matter is rather limited in comparison to those which address the measurement of locally reactive samples. Furthermore, the majority of papers published describe the use of two or more microphones whereas this paper focuses on the measurement with the pressure-particle velocity sensor (PU technique). For these reasons, the assumption that the sample is locally reactive is initially explored, so that the associated measurement errors can be quantified. Measurements in the impedance tube and in a semi-anechoic room are presented to validate the theoretical experiment. For samples with a high non-local reaction behavior, for which the measurement errors tend to be high, two different algorithms are proposed in order to minimize the associated errors.

The Reactive–Proactive Aggression Questionnaire: Differential Correlates of Reactive and Proactive Aggression in Adolescent Boys

PubMed Central

Raine, Adrian; Dodge, Kenneth; Loeber, Rolf; Gatzke-Kopp, Lisa; Lynam, Don; Reynolds, Chandra; Stouthamer-Loeber, Magda; Liu, Jianghong

2009-01-01

This study reports the development of the Reactive–Proactive Aggression Questionnaire (RPQ), and the differential correlates of these two forms of aggression. Antisocial, psychosocial and personality measures were obtained at ages 7 and 16 years in schoolboys, while the RPQ was administered to 334 of the boys at age 16 years. Confirmatory factor analysis indicated a significant fit for a two-factor proactive–reactive model that replicated from one independent subsample to another. Proactive aggression was uniquely characterized at age 7 by initiation of fights, strong-arm tactics, delinquency, poor school motivation, poor peer relationships, single-parent status, psychosocial adversity, substance-abusing parents, and hyperactivity, and at age 16 by a psychopathic personality, blunted affect, delinquency, and serious violent offending. Reactive aggression was uniquely characterized at age 16 by impulsivity, hostility, social anxiety, lack of close friends, unusual perceptual experiences, and ideas of reference. Findings confirm and extend the differential correlates of proactive–reactive aggression, and demonstrate that this brief but reliable and valid self-report instrument can be used to assess proactive and reactive aggression in child and adolescent samples. PMID:20798781

Cutting Edge: Nonobese Diabetic Mice Deficient in Chromogranin A Are Protected from Autoimmune Diabetes.

PubMed

Baker, Rocky L; Bradley, Brenda; Wiles, Timothy A; Lindsay, Robin S; Barbour, Gene; Delong, Thomas; Friedman, Rachel S; Haskins, Kathryn

2016-01-01

T cells reactive to β cell Ags are critical players in the development of autoimmune type 1 diabetes. Using a panel of diabetogenic CD4 T cell clones derived from the NOD mouse, we recently identified the β cell secretory granule protein, chromogranin A (ChgA), as a new autoantigen in type 1 diabetes. CD4 T cells reactive to ChgA are pathogenic and rapidly transfer diabetes into young NOD recipients. We report in this article that NOD.ChgA(-/-) mice do not develop diabetes and show little evidence of autoimmunity in the pancreatic islets. Using tetramer analysis, we demonstrate that ChgA-reactive T cells are present in these mice but remain naive. In contrast, in NOD.ChgA(+/+) mice, a majority of the ChgA-reactive T cells are Ag experienced. Our results suggest that the presence of ChgA and subsequent activation of ChgA-reactive T cells are essential for the initiation and development of autoimmune diabetes in NOD mice. Copyright © 2015 by The American Association of Immunologists, Inc.

Allocating scarce medical resources to the overweight.

PubMed

Furnham, Adrian; Loganathan, Niroosha; McClelland, Alastair

2010-01-01

A programmatic research effort investigated how lay people weigh information on hypothetical patients when making decisions regarding the allocation of scarce medical resources. This study is partly replicative and partly innovative, and looks particularly at whether overweight patients would be discriminated against in allocating resources. This study aims to determine the importance given to specific patient characteristics when lay participants are asked to allocate scarce medical resources. In all, 156 British adults (82 males, 73 females), aged 19 to 84 years, took part. There were few students. Participants completed a questionnaire requiring them to rank 16 hypothetical patients for access to a kidney dialysis machine.The demographic information presented regarding each hypothetical patient differed on four dimensions: gender, weight, mental health, and religiousness. There were significant main effects for gender, weight, and mental health; females, patients of normal weight, and the mentally well were ranked the highest priority for access to a kidney dialysis machine. Participants discriminated most regarding the weight of hypothetical patients. Different patient characteristics, unrelated to medical prognoses, particularly being overweight, may have an impact on decisions regarding the use of scarce medical resources.

Willingness to receive a hypothetical avian influenza vaccine among US military personnel in mid-deployment.

PubMed

Porter, Chad K; Fitamaurice, Gina; Tribble, David R; Armstrong, Adam W; Mostafa, Manal; Riddle, Mark S

2013-12-01

Though no avian influenza vaccine currently exists, development efforts have increased. Given recent reports of suboptimal vaccination rates among US military personnel, we sought to assess factors associated with a willingness to receive a hypothetical avian influenza vaccine. A self-administered questionnaire was completed by US military personnel during mid-deployment to Iraq, Afghanistan, and surrounding regions. Respondents were predominately male (86.2%), Army (72.1%), and enlisted (86.3%) with a mean age of 29.6 y. The majority (77.1%) agreed to receive an avian influenza vaccine if available. Exploratory factor analysis (EFA) identified two factors, vaccine importance and disease risk, that best described the individual perceptions and both were associated with an increased willingness to receive the hypothetical vaccine (OR: 8.2 and 1.6, respectively). Importantly, after controlling for these factors differences in the willingness to receive this hypothetical vaccine were observed across gender and branch of service. These results indicated that targeted education on vaccine safety and efficacy as well as disease risk may modify vaccination patterns in this population.

Willingness to receive a hypothetical avian influenza vaccine among US military personnel in mid-deployment

PubMed Central

Porter, Chad K; Fitamaurice, Gina; Tribble, David R; Armstrong, Adam W; Mostafa, Manal; Riddle, Mark S

2013-01-01

Though no avian influenza vaccine currently exists, development efforts have increased. Given recent reports of suboptimal vaccination rates among US military personnel, we sought to assess factors associated with a willingness to receive a hypothetical avian influenza vaccine. A self-administered questionnaire was completed by US military personnel during mid-deployment to Iraq, Afghanistan, and surrounding regions. Respondents were predominately male (86.2%), Army (72.1%), and enlisted (86.3%) with a mean age of 29.6 y. The majority (77.1%) agreed to receive an avian influenza vaccine if available. Exploratory factor analysis (EFA) identified two factors, vaccine importance and disease risk, that best described the individual perceptions and both were associated with an increased willingness to receive the hypothetical vaccine (OR: 8.2 and 1.6, respectively). Importantly, after controlling for these factors differences in the willingness to receive this hypothetical vaccine were observed across gender and branch of service. These results indicated that targeted education on vaccine safety and efficacy as well as disease risk may modify vaccination patterns in this population. PMID:23917256

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

Verberkmoes, Nathan C; Shah, Manesh B; Lankford, Patricia K

Rhodopseudomonas palustris is a purple nonsulfur anoxygenic phototrophic bacterium that is ubiquitous in soil and water. R. palustris is metabolically versatile with respect to energy generation and carbon and nitrogen metabolism. We have characterized and compared the baseline proteome of a R. palustris wild-type strain grown under six metabolic conditions. The methodology for proteome analysis involved protein fractionation by centrifugation, subsequent digestion with trypsin, and analysis of peptides by liquid chromatography coupled with tandem mass spectrometry. Using these methods, we identified 1664 proteins out of 4836 predicted proteins with conservative filtering constraints. A total of 107 novel hypothetical proteins andmore » 218 conserved hypothetical proteins were detected. Qualitative analyses revealed over 311 proteins exhibiting marked differences between conditions, many of these being hypothetical or conserved hypothetical proteins showing strong correlations with different metabolic modes. For example, five proteins encoded by genes from a novel operon appeared only after anaerobic growth with no evidence of these proteins in extracts of aerobically grown cells. Proteins known to be associated with specialized growth states such as nitrogen fixation, photoautotrophic, or growth on benzoate, were observed to be up-regulated under those states.« less

Detonative propagation and accelerative expansion of the Crab Nebula shock front.

PubMed

Gao, Yang; Law, Chung K

2011-10-21

The accelerative expansion of the Crab Nebula's outer envelope is a mystery in dynamics, as a conventional expanding blast wave decelerates when bumping into the surrounding interstellar medium. Here we show that the strong relativistic pulsar wind bumping into its surrounding nebula induces energy-generating processes and initiates a detonation wave that propagates outward to form the current outer edge, namely, the shock front, of the nebula. The resulting detonation wave, with a reactive downstream, then provides the needed power to maintain propagation of the shock front. Furthermore, relaxation of the curvature-induced reduction of the propagation velocity from the initial state of formation to the asymptotic, planar state of Chapman-Jouguet propagation explains the observed accelerative expansion. Potential richness in incorporating reactive fronts in the description of various astronomical phenomena is expected. © 2011 American Physical Society

Automated startup of the MIT research reactor

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

Kwok, K.S.

1992-01-01

This summary describes the development, implementation, and testing of a generic method for performing automated startups of nuclear reactors described by space-independent kinetics under conditions of closed-loop digital control. The technique entails first obtaining a reliable estimate of the reactor's initial degree of subcriticality and then substituting that estimate into a model-based control law so as to permit a power increase from subcritical on a demanded trajectory. The estimation of subcriticality is accomplished by application of the perturbed reactivity method. The shutdown reactor is perturbed by the insertion of reactivity at a known rate. Observation of the resulting period permitsmore » determination of the initial degree of subcriticality. A major advantage to this method is that repeated estimates are obtained of the same quantity. Hence, statistical methods can be applied to improve the quality of the calculation.« less

Relative merits of reactive and forward-look detection for wind-shear encounters during landing approach for various microburst escape strategies

NASA Technical Reports Server (NTRS)

Hinton, David A.

1990-01-01

The goal was to quantify the benefits of airborne forward-look windshear detection and to develop and test a candidate set of strategies for recovery from inadvertent microburst encounters during the landing approach, given the utilization of both reactive-only and forward-look windshear detection. Candidate strategies were developed and evaluated using a non-piloted simulation consisting of a simple point-mass performance model of a transport-category airplane flying through an analytical microburst model. The results indicate that the factor which most strongly effects a microburst recovery is the time at which the recovery is initiated. Forward-look alerts given 10 seconds prior to microburst entry permitted recoveries to be made with negligible altitude loss. The results also show that no single microburst scenario can be used to evaluate the relative merits of various recovery strategies. The type of alert used to initiate the recovery (reactive or forward-look) and the altitude of the microburst encounter had an effect on the type of recovery strategy that performed best. These factors may have serious implications for the design and certification of windshear systems.

Extended asymmetric hot region formation due to shockwave interactions following void collapse in shocked high explosive

NASA Astrophysics Data System (ADS)

Shan, Tzu-Ray; Wixom, Ryan R.; Thompson, Aidan P.

2016-08-01

In both continuum hydrodynamics simulations and also multimillion atom reactive molecular dynamics simulations of shockwave propagation in single crystal pentaerythritol tetranitrate (PETN) containing a cylindrical void, we observed the formation of an initial radially symmetric hot spot. By extending the simulation time to the nanosecond scale, however, we observed the transformation of the small symmetric hot spot into a longitudinally asymmetric hot region extending over a much larger volume. Performing reactive molecular dynamics shock simulations using the reactive force field (ReaxFF) as implemented in the LAMMPS molecular dynamics package, we showed that the longitudinally asymmetric hot region was formed by coalescence of the primary radially symmetric hot spot with a secondary triangular hot zone. We showed that the triangular hot zone coincided with a double-shocked region where the primary planar shockwave was overtaken by a secondary cylindrical shockwave. The secondary cylindrical shockwave originated in void collapse after the primary planar shockwave had passed over the void. A similar phenomenon was observed in continuum hydrodynamics shock simulations using the CTH hydrodynamics package. The formation and growth of extended asymmetric hot regions on nanosecond timescales has important implications for shock initiation thresholds in energetic materials.

Evaluating the expected effects of disclosure of patient safety incidents using hypothetical cases in Korea.

PubMed

Ock, Minsu; Choi, Eun Young; Jo, Min-Woo; Lee, Sang-Il

2018-01-01

To introduce disclosure of patient safety incidents (DPSI) into a specific country, evidence of the effectiveness of DPSI is essential. Since such a disclosure policy has not been adopted in South Korea, hypothetical cases can be used to measure the effectiveness of DPSI. We evaluated the effectiveness of DPSI using hypothetical cases in a survey with a sample of the Korean general public. We used 8 hypothetical cases reflecting 3 conditions: the clarity of medical errors, the severity of harm, and conducting DPSI. Face-to-face interviews with 700 people using structured questionnaires were conducted. Participants were asked to read each hypothetical case and give remarks on the following: their judgment of a situation as a medical error and of the requirement for an apology, the willingness to revisit or recommend physicians, the intention to file a medical lawsuit and commence criminal proceedings against physicians, the level of trust in physicians, and the expected amount of compensation. The results indicated favorable findings in support of DPSI; DPSI reduced the likelihood of perceiving a situation as a medical error, promoted willingness to revisit and recommend physicians, and discouraged the intention to file a medical lawsuit and take commence criminal proceedings against physicians. Furthermore, DPSI increased patients' trust scores in physicians and reduced the expected amount of compensation. The general public had positive attitudes towards DPSI in South Korea. This result provides empirical evidence for reducing the psychological burden that the introduction of DPSI may have on health professionals.

RDoC, DSM, and the reflex physiology of fear: A bio-dimensional analysis of the anxiety disorders spectrum

PubMed Central

Lang, Peter J.; McTeague, Lisa M.; Bradley, Margaret M.

2015-01-01

Evidence is presented supporting a dimension of defensive reactivity that varies across the anxiety disorder spectrum and is defined by physiological responses during threat-imagery challenges that covary with objective measures of psychopathology. Previous imagery studies of anxiety disorders are reviewed, highlighting that, regardless of contemporary diagnostic convention, reliable psychophysiological patterns emerge for patients diagnosed with circumscribed fear compared to those diagnosed with pervasive anxious-misery disorders. Based on the heuristic outlined by the Research Domain Criteria (RDoC) initiative, an exploratory transdiagnostic analysis is presented, based on a sample of 425 treatment-seeking patients from across the spectrum of DSM-IV anxiety diagnoses. Using a composite index of startle reflex and heart rate reactivity during idiographic-fear imagery for each patient, a defensive dimension was defined by ranking patients from most defensively reactive to least reactive and then creating five groups of equivalent size (quintile; N = 85). Subsequent analyses showed significant, parallel trends of diminishing reactivity in both electrodermal and facial EMG reactions across this defensive dimension. Negative affectivity, defined by questionnaire, and extent of functional interference, however, showed consistent, inverse trends with defensive reactivity -- as reports of distress increased, defensive reactivity was increasingly attenuated. Notably, representatives of each principal diagnosis appeared in each quintile, underscoring the reality of pronounced within-diagnosis heterogeneity in defensive reactivity. In concluding, we describe our new RDoC research project, focusing on the assessment of brain circuit function as it determines hypo/hyper reactivity to challenge—somatic and autonomic—and may relate to patients’ stress history and genetic inheritance. PMID:26877123

Trifluoperazine inhibits acetaminophen-induced hepatotoxicity and hepatic reactive nitrogen formation in mice and in freshly isolated hepatocytes.

PubMed

Banerjee, Sudip; Melnyk, Stepan B; Krager, Kimberly J; Aykin-Burns, Nukhet; McCullough, Sandra S; James, Laura P; Hinson, Jack A

2017-01-01

The hepatotoxicity of acetaminophen (APAP) occurs by initial metabolism to N-acetyl-p-benzoquinone imine which depletes GSH and forms APAP-protein adducts. Subsequently, the reactive nitrogen species peroxynitrite is formed from nitric oxide (NO) and superoxide leading to 3-nitrotyrosine in proteins. Toxicity occurs with inhibited mitochondrial function. We previously reported that in hepatocytes the nNOS (NOS1) inhibitor NANT inhibited APAP toxicity, reactive nitrogen and oxygen species formation, and mitochondrial dysfunction. In this work we examined the effect of trifluoperazine (TFP), a calmodulin antagonist that inhibits calcium induced nNOS activation, on APAP hepatotoxicity and reactive nitrogen formation in murine hepatocytes and in vivo . In freshly isolated hepatocytes TFP inhibited APAP induced toxicity, reactive nitrogen formation (NO, GSNO, and 3-nitrotyrosine in protein), reactive oxygen formation (superoxide), loss of mitochondrial membrane potential, decreased ATP production, decreased oxygen consumption rate, and increased NADH accumulation. TFP did not alter APAP induced GSH depletion in the hepatocytes or the formation of APAP protein adducts which indicated that reactive metabolite formation was not inhibited. Since we previously reported that TFP inhibits the hepatotoxicity of APAP in mice without altering hepatic APAP-protein adduct formation, we examined the APAP treated mouse livers for evidence of reactive nitrogen formation. 3-Nitrotyrosine in hepatic proteins and GSNO were significantly increased in APAP treated mouse livers and decreased in the livers of mice treated with APAP plus TFP. These data are consistent with a hypothesis that APAP hepatotoxicity occurs with altered calcium metabolism, activation of nNOS leading to increased reactive nitrogen formation, and mitochondrial dysfunction.

Developmental change in amygdala reactivity during adolescence: effects of family history of depression and stressful life events.

PubMed

Swartz, Johnna R; Williamson, Douglas E; Hariri, Ahmad R

2015-03-01

Although heightened amygdala reactivity is observed in patients with major depression, two critical gaps in our knowledge remain. First, it is unclear whether heightened amygdala reactivity is a premorbid vulnerability or a consequence of the disorder. Second, it is unknown how and when this neural phenotype develops. The authors sought to address these gaps by evaluating developmental change in threat-related amygdala reactivity in adolescents at high or low risk for depression based on family history, before onset of disorder. At baseline and again 2 years later, adolescents (initially 11-15 years of age) participated in a functional MRI paradigm that elicited threat-related amygdala reactivity. After quality control, data were available for 232 adolescents at wave 1 and 197 adolescents at wave 2; longitudinal data meeting quality control at both waves were available for 157 of these participants. Change in amygdala reactivity was assessed as a function of family history of depression and severity of stressful life events. Threat-related amygdala reactivity increased with age in participants with a positive family history regardless of the severity of life stress reported, and it increased in adolescents with a negative family history who reported relatively severe life stress. These changes in amygdala reactivity with age occurred in the absence of clinical disorder or increases in depressive symptoms. These results suggest that heightened amygdala reactivity emerges during adolescence, prior to the development of depression, as a function of familial risk or, in the absence of familial risk, stressful life events.

Investigation of an algorithm for anti HCV EIA reactivity in blood donor screening in Turkey in the absence of nucleic acid amplification screening.

PubMed

Karakoc, Ayse Esra; Berkem, Rukiye; Irmak, Hasan; Demiroz, Ali Pekcan; Yenicesu, Idil; Ertugrul, Nigar; Arslan, Önder; Kemahli, Sabri; Yilmaz, Sevinc; Ozcebe, Osman; Kara, Abdurrahman; Ozet, Gulsum; Acikgoz, Ziya Cibali; Acikgoz, Tulin

2017-10-01

In this study we aimed to propose an algorithm for initial anti HCV EIA reactive blood donations in Turkey where nucleic acid amplification tests are not yet obligatory for donor screening. A total of 416 anti HCV screening test reactive donor samples collected from 13 blood centers from three cities in Turkey were tested in duplicate by Ortho HCV Ab Version 3.0 and Radim HCV Ab. All the repeat reactive samples were tested by INNO-LIA HCV Ab 3.0 or Chiron RIBA HCV 3.0 and Abbott Real Time HCV. Intra-assay correlations were calculated with Pearson r test. ROC analysis was used to study the relationship between EIA tests and the confirmatory tests. The number of repeat reactive results with Ortho EIA were 221 (53.1%) whereas that of microEIA, 62 (14.9%). Confirmed positivity rate was 14.6% (33/226) by RIBA and 10.6% (24/226) by NAT. Reactive PCR results were predicted with 100% sensitivity and 95% specificity with S/CO levels of 8.1 with Ortho EIA and 3.4 with microEIA. Repeat reactivity rates declined with a second HCV antibody assay. Samples repeat reactive with one HCV antibody test and negative with the other were all NAT negative. All the NAT reactive samples were RIBA positive. None of the RIBA indeterminate or negative samples were NAT reactive. Considering the threshold values for EIA kits determined by ROC analysis NAT was decided to be performed for the samples above the threshold value and a validated supplemental HCV antibody test for the samples below. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of reagent rotational excitation on the H + CHD₃ → H₂ + CD₃ reaction: a seven dimensional time-dependent wave packet study.

PubMed

Zhang, Zhaojun; Zhang, Dong H

2014-10-14

Seven-dimensional time-dependent wave packet calculations have been carried out for the title reaction to obtain reaction probabilities and cross sections for CHD3 in J0 = 1, 2 rotationally excited initial states with k0 = 0 - J0 (the projection of CHD3 rotational angular momentum on its C3 axis). Under the centrifugal sudden (CS) approximation, the initial states with the projection of the total angular momentum on the body fixed axis (K0) equal to k0 are found to be much more reactive, indicating strong dependence of reactivity on the orientation of the reagent CHD3 with respect to the relative velocity between the reagents H and CHD3. However, at the coupled-channel (CC) level this dependence becomes much weak although in general the K0 specified cross sections for the K0 = k0 initial states remain primary to the overall cross sections, implying the Coriolis coupling is important to the dynamics of the reaction. The calculated CS and CC integral cross sections obtained after K0 averaging for the J0 = 1, 2 initial states with all different k0 are essentially identical to the corresponding CS and CC results for the J0 = 0 initial state, meaning that the initial rotational excitation of CHD3 up to J0 = 2, regardless of its initial k0, does not have any effect on the total cross sections for the title reaction, and the errors introduced by the CS approximation on integral cross sections for the rotationally excited J0 = 1, 2 initial states are the same as those for the J0 = 0 initial state.

Clinical features and treatment outcomes of Langerhans cell histiocytosis: a nationwide survey from Korea histiocytosis working party.

PubMed

Kim, Bo Eun; Koh, Kyung-Nam; Suh, Jin Kyung; Im, Ho Joon; Song, Joon Sup; Lee, Ji Won; Kang, Hyoung Jin; Park, Kyung Duck; Shin, Hee Young; Choi, Hyoung Soo; Lee, Soo Hyun; Yoo, Keon Hee; Sung, Ki Woong; Koo, Hong Hoe; Jung, Hye Lim; Chung, Nak-Gyun; Cho, Bin; Kim, Hack Ki; Lyu, Chuhl Joo; Baek, Hee Jo; Kook, Hoon; Park, Jun Eun; Park, Hyeon Jin; Park, Byung-Kiu; Yoo, Eun Sun; Ryu, Kyung Ha; Lee, Kun Soo; Kim, Heung Sik; Lee, Jae Min; Park, Eun Sil; Yoon, Hoi Soo; Lee, Kwang Chul; Lee, Mee Jeong; Lim, Young Tak; Kim, Hwang Min; Park, Sang Kyu; Park, Jeong-A; Kim, Soon Ki; Park, Meerim; Lim, Yeon-Jung; Lee, Young Ho; Seo, Jong Jin

2014-03-01

A nationwide survey was conducted to clarify the clinical features and outcomes of Korean children with Langerhans cell histiocytosis (LCH). Korea Histiocytosis Working Party analyzed the data of 603 patients who were diagnosed with LCH between 1986 and 2010 from 28 institutions in Korea. Median age at diagnosis was 65 months (range, 0 to 276 mo). Bone was the most frequently affected organ (79.6%) followed by skin (19.2%). Initially, 419 patients (69.5%) had single-system involvement (SS), 85 (14.1%) with multisystem (MS) disease without risk organ involvement (MS-RO), and 99 (16.4%) multisystem disease with risk organ involvement (MS-RO). The 5-year overall survival (OS) rates in the SS, MS-RO, and MS-RO groups were 99.8%, 98.4%, and 77.0%, respectively (P<0.001), and the 5-year reactivation rates were 17.9%, 33.5%, and 34.3%, respectively (P<0.001). The OS rate was lower in patients with RO involvement (P=0.025) and lack of response to initial treatment (P=0.001). MS involvement (P=0.036) was an independent risk factor for reactivation. Permanent consequences were documented in 99 patients (16.4%). Reactivation of disease, MS involvement, and age at diagnosis ≤ 2 years were associated with higher incidence of permanent consequences. This study emphasized that further efforts are required to improve survival of MS-RO patients and reduce reactivation in younger patients with MS involvement.

Baseline psychophysiological and cortisol reactivity as a predictor of PTSD treatment outcome in virtual reality exposure therapy

PubMed Central

Norrholm, Seth Davin; Jovanovic, Tanja; Gerardi, Maryrose; Breazeale, Kathryn G.; Price, Matthew; Davis, Michael; Duncan, Erica; Ressler, Kerry J.; Bradley, Bekh; Rizzo, Albert; Tuerk, Peter W.; Rothbaum, Barbara O.

2017-01-01

Baseline cue-dependent physiological reactivity may serve as an objective measure of posttraumatic stress disorder (PTSD) symptoms. Additionally, prior animal model and psychological studies would suggest that subjects with greatest symptoms at baseline may have the greatest violation of expectancy to danger when undergoing exposure based psychotherapy; thus treatment approaches which enhanced the learning under these conditions would be optimal for those with maximal baseline cue-dependent reactivity. However methods to study this hypothesis objectively are lacking. Virtual reality (VR) methodologies have been successfully employed as an enhanced form of imaginal prolonged exposure therapy for the treatment of PTSD. Our goal was to examine the predictive nature of initial psychophysiological (e.g., startle, skin conductance, heart rate) and stress hormone responses (e.g., cortisol) during presentation of VR-based combat-related stimuli on PTSD treatment outcome. Combat veterans with PTSD underwent 6 weeks of VR exposure therapy combined with either D-cycloserine (DCS), alprazolam (ALP), or placebo (PBO). In the DCS group, startle response to VR scenes prior to initiation of treatment accounted for 76% of the variance in CAPS change scores, p < 0.001, in that higher responses predicted greater changes in symptom severity over time. Additionally, baseline cortisol reactivity was inversely associated with treatment response in the ALP group, p = 0.04. We propose that baseline cue-activated physiological measures will be sensitive to predicting patients’ level of response to exposure therapy, in particular in the presence of enhancement (e.g., DCS). PMID:27183343

Integrated Evaluation of Latent Viral Reactivation During Spaceflight

NASA Technical Reports Server (NTRS)

Pierson, Duane L.; Paloski, W. H. (Technical Monitor)

2000-01-01

This application proposes a continuation of our current effort, which has provided the first demonstration of viral reactivation during space flight. We have used the herpesvirus EBV as a model for latent viral reactivation and have shown that increased amounts of EBV DNA were shed by astronauts during space flight. Analysis of the Antarctic space flight analog indicated that the frequency of viral shedding may also increase (along with the increased numbers of virus) during long periods of isolation. However, a number of critical questions remain before the findings may be considered a significant health risk during extended space flight. These include: Are other latent viruses (e.g., other herpesviruses and polyornaviruses) in addition to EBV also reactivated and shed more frequently and/or in higher numbers during space flight? Is the viral reactivation observed in space flight and ground-based analogs mediated through the hypothalamus-pituitary-adrenal (HPA) axis resulting in a decreased cell-mediated immune response? How does detection of viral DNA by PCR analysis correlate with infectious virus? How does the amount of virus found during flight compare with viral levels observed in acute/chronic viral illnesses and in control individuals? This expanded study will examine the phenomenon of viral reactivation from the initiating stress through the HPA axis with the accompanying suppression of the immune system resulting in viral reactivation. This information is essential to determine if latent viral reactivation among crewmembers represents a sufficient medical risk to space travel to require the development of suitable countermeasures.

Elevated and cross‐responsive CD1a‐reactive T cells in bee and wasp venom allergic individuals

PubMed Central

Subramaniam, Sumithra; Aslam, Aamir; Misbah, Siraj A.; Salio, Mariolina; Cerundolo, Vincenzo; Moody, D Branch

2015-01-01

The role of CD1a‐reactive T cells in human allergic disease is unknown. We have previously shown that circulating CD1a‐reactive T cells recognize neolipid antigens generated by bee and wasp venom phospholipase, and here tested the hypothesis that venom‐responsive CD1a‐reactive T cells associate with venom allergy. Circulating T cells from bee and wasp venom allergic individuals, before and during immunotherapy, were exposed to CD1a‐transfected K562 cells in the presence of wasp or bee venom. T‐cell response was evaluated based on IFNγ, GM‐CSF, and IL‐13 cytokine production. Venom allergic individuals showed significantly higher frequencies of IFN‐γ, GM‐CSF, and IL‐13 producing CD1a‐reactive T cells responsive to venom and venom‐derived phospholipase than healthy individuals. Venom‐responsive CD1a‐reactive T cells were cross‐responsive between wasp and bee suggesting shared pathways of allergenicity. Frequencies of CD1a‐reactive T cells were initially induced during subcutaneous immunotherapy, peaking by weeks 5, but then reduced despite escalation of antigen dose. Our current understanding of venom allergy and immunotherapy is largely based on peptide and protein‐specific T cell and antibody responses. Here, we show that lipid antigens and CD1a‐reactive T cells associate with the allergic response. These data have implications for mechanisms of allergy and approaches to immunotherapy. PMID:26518614

Skin Test Reactivity to Hymenoptera Venom after Venom Immunotherapy Correlates Inversely with the IgG/IgE Ratio.

PubMed

Saulite, Ieva; Hoetzenecker, Wolfram; Guenova, Emmanuella; Schmid-Grendelmeier, Peter; Glatz, Martin

2017-01-01

Skin test reactivity to hymenoptera venom and venom-specific IgE are important for diagnosing venom allergy and deciding on the appropriate allergen for venom immunotherapy (VIT). Longitudinal data on skin test reactivity during VIT and their correlation with venom-specific immunoglobulin (Ig)E and IgG are scarce. We retrospectively analyzed shifts in skin test reactivity and serum levels of venom-specific IgE and IgG in patients allergic to hymenoptera venom before the initiation of VIT with ultrarush therapy and after ≥3 years of VIT. Fifty-four patients received ultrarush desensitization and subsequent VIT with wasp venom, 26 with honeybee venom, and 8 with both wasp and honeybee venom. Hymenoptera-specific skin test reactivity decreased during VIT in most patients, and became negative in 8% of the wasp-allergic patients and in 25% of the honeybee-allergic patients. Serum levels of venom-specific IgE positively correlated to skin test reactivity before VIT, but did not change significantly during VIT. IgG serum levels and the IgG/IgE ratio increased during VIT in most patients. A high IgG/IgE ratio correlated with low skin test reactivity after ≥3 years of VIT. The correlation between a high venom-specific IgG/IgE ratio and low skin test reactivity after VIT may be interesting for future investigations that assess its role as a potential marker for VIT efficacy. © 2017 S. Karger AG, Basel.

Calibrating reaction rates for the CREST model

NASA Astrophysics Data System (ADS)

Handley, Caroline A.; Christie, Michael A.

2017-01-01

The CREST reactive-burn model uses entropy-dependent reaction rates that, until now, have been manually tuned to fit shock-initiation and detonation data in hydrocode simulations. This paper describes the initial development of an automatic method for calibrating CREST reaction-rate coefficients, using particle swarm optimisation. The automatic method is applied to EDC32, to help develop the first CREST model for this conventional high explosive.

Crossing the dividing surface of transition state theory. IV. Dynamical regularity and dimensionality reduction as key features of reactive trajectories

NASA Astrophysics Data System (ADS)

Lorquet, J. C.

2017-04-01

The atom-diatom interaction is studied by classical mechanics using Jacobi coordinates (R, r, θ). Reactivity criteria that go beyond the simple requirement of transition state theory (i.e., PR* > 0) are derived in terms of specific initial conditions. Trajectories that exactly fulfill these conditions cross the conventional dividing surface used in transition state theory (i.e., the plane in configuration space passing through a saddle point of the potential energy surface and perpendicular to the reaction coordinate) only once. Furthermore, they are observed to be strikingly similar and to form a tightly packed bundle of perfectly collimated trajectories in the two-dimensional (R, r) configuration space, although their angular motion is highly specific for each one. Particular attention is paid to symmetrical transition states (i.e., either collinear or T-shaped with C2v symmetry) for which decoupling between angular and radial coordinates is observed, as a result of selection rules that reduce to zero Coriolis couplings between modes that belong to different irreducible representations. Liapunov exponents are equal to zero and Hamilton's characteristic function is planar in that part of configuration space that is visited by reactive trajectories. Detailed consideration is given to the concept of average reactive trajectory, which starts right from the saddle point and which is shown to be free of curvature-induced Coriolis coupling. The reaction path Hamiltonian model, together with a symmetry-based separation of the angular degree of freedom, provides an appropriate framework that leads to the formulation of an effective two-dimensional Hamiltonian. The success of the adiabatic approximation in this model is due to the symmetry of the transition state, not to a separation of time scales. Adjacent trajectories, i.e., those that do not exactly fulfill the reactivity conditions have similar characteristics, but the quality of the approximation is lower. At higher energies, these characteristics persist, but to a lesser degree. Recrossings of the dividing surface then become much more frequent and the phase space volumes of initial conditions that generate recrossing-free trajectories decrease. Altogether, one ends up with an additional illustration of the concept of reactive cylinder (or conduit) in phase space that reactive trajectories must follow. Reactivity is associated with dynamical regularity and dimensionality reduction, whatever the shape of the potential energy surface, no matter how strong its anharmonicity, and whatever the curvature of its reaction path. Both simplifying features persist during the entire reactive process, up to complete separation of fragments. The ergodicity assumption commonly assumed in statistical theories is inappropriate for reactive trajectories.

Gender differences in intimate-conflict initiation and escalation tendencies.

PubMed

Winstok, Zeev; Smadar-Dror, Ronit; Weinberg, Michael

2018-05-01

According to gender motivation theory, men are driven by a desire to enhance their status; whereas, women are motivated by a desire to reduce risk, and the behavioral expressions of those motivations are context-dependent. In order to test this theory in the context of intimate relationships, this study compared men's and women's escalatory tendencies in the initial development of intimate conflict. These tendencies were conceptualized in terms of four attributes: two attributes that represent response intention (decision and style) and two others that represent motivations for that intention (putting one's partner in his or her place and avoiding conflict). These attributes were measured in the context of five hypothetical situations. Each of those scenarios involved potential escalation of intimate conflict, following an intimate partner's aggressive verbal demand. The study involved a convenience sample of 403 male and female participants. The findings show that, in the initial steps of intimate-conflict development, women tend toward escalation more than men. The findings also show that the escalatory tendency, as conceptualized and measured using the examined scenarios, corresponds to actual behavior exhibited in the resolution of common issues in the couples' lives. These findings reinforce gender motivation theory. © 2018 Wiley Periodicals, Inc.

Oblique contractional reactivation of inherited heterogeneities: Cause for arcuate orogens

PubMed Central

Sokoutis, D.; Willingshofer, E.; Brun, J.‐P.; Gueydan, F.; Cloetingh, S.

2017-01-01

Abstract We use lithospheric‐scale analog models to study the reactivation of pre‐existing heterogeneities under oblique shortening and its relation to the origin of arcuate orogens. Reactivation of inherited rheological heterogeneities is an important mechanism for localization of deformation in compressional settings and consequent initiation of contractional structures during orogenesis. However, the presence of an inherited heterogeneity in the lithosphere is in itself not sufficient for its reactivation once the continental lithosphere is shortened. The heterogeneity orientation is important in determining if reactivation occurs and to which extent. This study aims at giving insights on this process by means of analog experiments in which a linear lithospheric heterogeneity trends with various angles to the shortening direction. In particular, the key parameter investigated is the orientation (angle α) of a strong domain (SD) with respect to the shortening direction. Experimental results show that angles α ≥ 75° (high obliquity) allow for reactivation along the entire SD and the development of a linear orogen. For α ≤ 60° (low obliquity) the models are characterized by the development of an arcuate orogen, with the SD remaining partially non‐reactivated. These results provide a new mechanism for the origin of some arcuate orogens, in which orocline formation was not driven by indentation or subduction processes, but by oblique shortening of inherited heterogeneities, as exemplified by the Ouachita orogen of the southern U.S. PMID:28670046

Reactivation of Herpesvirus in Patients With Hepatitis C Treated With Direct-Acting Antiviral Agents.

PubMed

Perelló M, Christie; Fernández-Carrillo, Carlos; Londoño, María-Carlota; Arias-Loste, Teresa; Hernández-Conde, Marta; Llerena, Susana; Crespo, Javier; Forns, Xavier; Calleja, José Luis

2016-11-01

We performed a case-series analysis of reactivation of herpesvirus in patients with hepatitis C virus (HCV) infection treated with direct-acting antiviral (DAA) agents. We collected data from 576 patients with HCV infection treated with DAA combinations at 3 hospitals in Spain, from November 2014 through November 2015. We also collected data from a control population (230 HCV-infected patients, matched for sex and age; 23 untreated and 213 treated with interferon-based regimens). Herpesvirus was reactivated in 10 patients who received DAA therapy (7 patients had cirrhosis and 3 patients had received liver transplants), a median of 8 weeks after the therapy was initiated. None of the controls had herpesvirus reactivation. Patients with herpesvirus reactivation were receiving the DAA agents sofosbuvir with ledipasvir (with or without ribavirin, 7/10), ombitasvir with paritaprevir and ritonavir plus dasabuvir (with or without ribavirin, 2/10), or sofosbuvir with simeprevir plus ribavirin (1/10). Two of the 10 patients developed postherpetic neuralgia and 1 patient developed kerato-uveitis. All 10 patients with herpesvirus reactivation achieved a sustained virologic response. Immune changes that follow clearance of HCV might lead to reactivation of other viruses, such as herpesvirus. Patients with HCV infection suspected of having herpesvirus infection should be treated immediately. Some groups also might be screened for herpesvirus infection. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

Water-Gas Shift and Methane Reactivity on Reducible Perovskite-Type Oxides

PubMed Central

2015-01-01

Comparative (electro)catalytic, structural, and spectroscopic studies in hydrogen electro-oxidation, the (inverse) water-gas shift reaction, and methane conversion on two representative mixed ionic–electronic conducting perovskite-type materials La0.6Sr0.4FeO3−δ (LSF) and SrTi0.7Fe0.3O3−δ (STF) were performed with the aim of eventually correlating (electro)catalytic activity and associated structural changes and to highlight intrinsic reactivity characteristics as a function of the reduction state. Starting from a strongly prereduced (vacancy-rich) initial state, only (inverse) water-gas shift activity has been observed on both materials beyond ca. 450 °C but no catalytic methane reforming or methane decomposition reactivity up to 600 °C. In contrast, when starting from the fully oxidized state, total methane oxidation to CO2 was observed on both materials. The catalytic performance of both perovskite-type oxides is thus strongly dependent on the degree/depth of reduction, on the associated reactivity of the remaining lattice oxygen, and on the reduction-induced oxygen vacancies. The latter are clearly more reactive toward water on LSF, and this higher reactivity is linked to the superior electrocatalytic performance of LSF in hydrogen oxidation. Combined electron microscopy, X-ray diffraction, and Raman measurements in turn also revealed altered surface and bulk structures and reactivities. PMID:26045733

Oxidation of trichloroethylene, toluene, and ethanol vapors by a partially saturated permeable reactive barrier

NASA Astrophysics Data System (ADS)

Mahmoodlu, Mojtaba G.; Hassanizadeh, S. Majid; Hartog, Niels; Raoof, Amir

2014-08-01

The mitigation of volatile organic compound (VOC) vapors in the unsaturated zone largely relies on the active removal of vapor by ventilation. In this study we considered an alternative method involving the use of solid potassium permanganate to create a horizontal permeable reactive barrier for oxidizing VOC vapors. Column experiments were carried out to investigate the oxidation of trichloroethylene (TCE), toluene, and ethanol vapors using a partially saturated mixture of potassium permanganate and sand grains. Results showed a significant removal of VOC vapors due to the oxidation. We found that water saturation has a major effect on the removal capacity of the permeable reactive layer. We observed a high removal efficiency and reactivity of potassium permanganate for all target compounds at the highest water saturation (Sw = 0.6). A change in pH within the reactive layer reduced oxidation rate of VOCs. The use of carbonate minerals increased the reactivity of potassium permanganate during the oxidation of TCE vapor by buffering the pH. Reactive transport of VOC vapors diffusing through the permeable reactive layer was modeled, including the pH effect on the oxidation rates. The model accurately described the observed breakthrough curve of TCE and toluene vapors in the headspace of the column. However, miscibility of ethanol in water in combination with produced water during oxidation made the modeling results less accurate for ethanol. A linear relationship was found between total oxidized mass of VOC vapors per unit volume of permeable reactive layer and initial water saturation. This behavior indicates that pH changes control the overall reactivity and longevity of the permeable reactive layer during oxidation of VOCs. The results suggest that field application of a horizontal permeable reactive barrier can be a viable technology against upward migration of VOC vapors through the unsaturated zone.

Understanding the Reactivity of Lunar Dust for Future Lunar Missions

NASA Technical Reports Server (NTRS)

Wallace, William; Taylor, L. A.; Jeevarajan, Antony

2009-01-01

During the Apollo missions, dust was found to cause numerous problems for various instruments and systems. Additionally, the dust may have caused momentary health issues for some of the astronauts. Therefore, the plan to resume robotic and manned missions to the Moon in the next decade has led to a renewed interest in the properties of lunar dust, ranging from geological to chemical to toxicological. An important property to understand is the reactivity of the dust particles. Due to the lack of an atmosphere on the Moon, there is nothing to protect the lunar soil from ultraviolet radiation, solar wind, and meteorite impacts. These processes could all serve to activate the soil, or produce reactive surface species. On the Moon, these species can be maintained for millennia without oxygen or water vapor present to satisfy the broken bonds. Unfortunately, the Apollo dust samples that were returned to Earth were inadvertently exposed to the atmosphere, causing them to lose their reactive characteristics. In order to aid in the preparation of mitigation techniques prior to returning to the Moon, we measured the ability of lunar dust, lunar dust simulant, and quartz samples to produce hydroxyl radicals in solution[1]. As a first approximation of meteorite impacts on the lunar surface, we ground samples using a mortar and pestle. Our initial studies showed that all three test materials (lunar dust (62241), lunar dust simulant (JSC-1Avf), and quartz) produced hydroxyl radicals after grinding and mixing with water. However, the radical production of the ground lunar dust was approximately 10-fold and 3-fold greater than quartz and JSC-1 Avf, respectively. These reactivity differences between the different samples did not correlate with differences in specific surface area. The increased reactivity produced for the quartz by grinding was attributed to the presence of silicon- or oxygen-based radicals on the surface, as had been seen previously[2]. These radicals may also play a part in the reactivity of the lunar dust and lunar simulant. However, other factors would seem to be required to account for the greatly increased reactivity of the lunar soil. It was proposed that nanometer-size Fe 0 (zero valent) particles in the lunar soil might play a role, as they are not present in quartz or lunar dust simulant. The present work has been performed with the aim of understanding the origin of the considerable reactivity of lunar dust[3]. We have ground 8 lunar soils of varying maturity and source (highland or mare) and measured the hydroxyl-radical production and decay of the reactivity. It was determined that there is a direct correlation between the reactivity and the amount of nanophase metallic iron particles (as a function of soil maturity, I s/FeO, in which Is is the amount of iron present as nanophase iron particles present and FeO is the total iron content) in the samples; thus, the highland soils, with their lesser total FeO content, are less reactive than ground mare soils. Additionally, grinding of nanophase iron simulant [4] showed reactivity in line with the lunar soils and much greater than lunar dust simulant or quartz. Studies aimed at determining the time required to deactivate the reactive soils in a habitable environment showed that the average time to reach 50% of the initial reactivity was approximately 3.5 hours. However, even after one week, none of the soils had returned completely to its unground level of reactivity. In contrast to the reactivity results, there was no obvious correlation between the maturity of the soil and its deactivation time. These results provide the first chemical reactivity and persistence values as an important property of lunar soils, data that is paramount as mankind prepares to return to the Moon.

Factors Associated with Jealousy over Real and Imagined Infidelity: An Examination of the Social-Cognitive and Evolutionary Psychology Perspectives

ERIC Educational Resources Information Center

Harris, Christine R.

2003-01-01

Three hundred fifty-eight undergraduates completed anonymous questionnaires regarding jealousy over a mate's infidelity. More men than women predicted that sexual infidelity would be worse than emotional infidelity when given the forced-choice hypothetical measures used in previous work. When some of the implications of hypothetical infidelity…

Choices of wilderness environments -- differences between real and hypothetical choice situations

Treesearch

Jean T. Beaulieu; Richard Schreyer

1985-01-01

Factors considered most critical in selecting a specific wilderness environment in which to recreate are likely to vary depending upon the type of environment involved, the range and extent of experience of the recreationists, and the situational context of the decision (whether a real or a hypothetical decision was made). This study examines differences in factors...

The Ability of Children with Language Impairment to Dissemble Emotions in Hypothetical Scenarios and Natural Situations

ERIC Educational Resources Information Center

Brinton, Bonnie; Fujiki, Martin; Hurst, Noel Quist; Jones, Emily Rowberry; Spackman, Matthew P.

2015-01-01

Purpose: This study examined the ability of children with language impairment (LI) to dissemble (hide) emotional reactions when socially appropriate to do so. Method: Twenty-two children with LI and their typically developing peers (7;1-10;11 [years;months]) participated in two tasks. First, participants were presented with hypothetical scenarios…

Further Sensitivity Analysis of Hypothetical Policies to Limit Energy-Related Carbon Dioxide Emissions

EIA Publications

2013-01-01

This analysis supplements the Annual Energy Outlook 2013 alternative cases which imposed hypothetical carbon dioxide emission fees on fossil fuel consumers. It offers further cases that examine the impacts of fees placed only on the emissions from electric power facilities, impacts of returning potential revenues to consumers, and two cap-and-trade policies.

Valuing hypothetical wildfire impacts with a Kuhn–Tucker model of recreation demand

Treesearch

Jose Sanchez; Ken Baerenklau; Armando Gonzalez-Caban

2016-01-01

This study uses a nonmarket valuation method to investigate the recreation values of the San Jacinto Wilderness in southern California. The analysis utilizes survey data from a stated-choice experiment involving backcountry visitors who responded to questions about hypothetical wildfire burn scenarios. Benefits of landscape preservation are derived using a Kuhn-Tucker...

Preferences for Prolonging Life: A Prospect Theory Approach

ERIC Educational Resources Information Center

Winter, Laraine; Lawton, M. Powell; Ruckdeschel, Katy

2003-01-01

Kahneman and Tversky's (1979) Prospect theory was tested as a model of preferences for prolonging life under various hypothetical health statuses. A sample of 384 elderly people living in congregate housing (263 healthy, 131 frail) indicated how long (if at all) they would want to live under each of nine hypothetical health conditions (e.g.,…

Social Knowledge in Children with Language Impairments: Examination of Strategies, Predicted Consequences, and Goals in Peer Conflict Situations

ERIC Educational Resources Information Center

Timler, Geralyn R.

2008-01-01

This study investigated social knowledge in school-age children, aged 8-12 years, with and without language impairment (LI and TD groups). A hypothetical peer conflict task was administered to examine the relationship among prosocial responses and parent/teacher ratings of children's social behaviours. Stimuli included 12 hypothetical peer…

Developing a Hypothetical Multi-Dimensional Learning Progression for the Nature of Matter

ERIC Educational Resources Information Center

Stevens, Shawn Y.; Delgado, Cesar; Krajcik, Joseph S.

2010-01-01

We describe efforts toward the development of a hypothetical learning progression (HLP) for the growth of grade 7-14 students' models of the structure, behavior and properties of matter, as it relates to nanoscale science and engineering (NSE). This multi-dimensional HLP, based on empirical research and standards documents, describes how students…

HYTESS 2: A Hypothetical Turbofan Engine Simplified Simulation with multivariable control and sensor analytical redundancy

NASA Technical Reports Server (NTRS)

Merrill, W. C.

1986-01-01

A hypothetical turbofan engine simplified simulation with a multivariable control and sensor failure detection, isolation, and accommodation logic (HYTESS II) is presented. The digital program, written in FORTRAN, is self-contained, efficient, realistic and easily used. Simulated engine dynamics were developed from linearized operating point models. However, essential nonlinear effects are retained. The simulation is representative of the hypothetical, low bypass ratio turbofan engine with an advanced control and failure detection logic. Included is a description of the engine dynamics, the control algorithm, and the sensor failure detection logic. Details of the simulation including block diagrams, variable descriptions, common block definitions, subroutine descriptions, and input requirements are given. Example simulation results are also presented.

Potential safety benefits of intelligent cruise control systems.

PubMed

Chira-Chavala, T; Yoo, S M

1994-04-01

Potential safety impact of a hypothetical intelligent cruise control system (ICCS) is evaluated in terms of changes in traffic accidents and some traffic operation characteristics affecting safety. The analysis of changes in traffic accidents is accomplished by in-depth examinations of police accident reports for four major counties in California. The evaluation of changes in traffic operation characteristics affecting safety is accomplished by vehicle simulation. The accident analysis reveals that the use of the hypothetical ICCS could potentially reduce traffic accidents by up to 7.5%. Preliminary vehicle simulation results based on a 10-vehicle convoy indicate that the use of the hypothetical ICCS could reduce frequencies of hard acceleration and deceleration, enhance speed harmonization among vehicles, and reduce incidence of "less-safe" headway.

Experimental philosophy of actual and counterfactual free will intuitions.

PubMed

Feltz, Adam

2015-11-01

Five experiments suggested that everyday free will and moral responsibility judgments about some hypothetical thought examples differed from free will and moral responsibility judgments about the actual world. Experiment 1 (N=106) showed that free will intuitions about the actual world measured by the FAD-Plus poorly predicted free will intuitions about a hypothetical person performing a determined action (r=.13). Experiments 2-5 replicated this result and found the relations between actual free will judgments and free will judgments about hypothetical determined or fated actions (rs=.22-.35) were much smaller than the differences between them (ηp(2)=.2-.55). These results put some pressure on theoretical accounts of everyday intuitions about freedom and moral responsibility. Copyright © 2015 Elsevier Inc. All rights reserved.

One dimensional shock Initiation of UK Comp B

NASA Astrophysics Data System (ADS)

Burns, Malcolm

2017-06-01

Ten shock initiation experiments have been carried out on the UK isostatically pressed Composition B (59.5% RDX, 39.5% TNT, 1% wax) comprising of seven sustained pulse experiments with input pressures ranging from 2.89 to 9.86 GPa and three short shock experiments using the embedded gauge technique at the Los Alamos National Laboratory gas gun facility. The evolution of the reactive growth at and behind the shock front has been measured along with the run to detonation distance. These data have been used to create the Pop plot and hugoniot states for the UK Comp B. The shock initiation behavior of the UK Comp B has been compared to that of the equivalent US Composition. The reactive growth shows a feature that was observed in the US composition in which the wave profiles dispay a high level of pre-detonation noise. This was hypothesized to be due to a piezoelectric effect in the RDX crystals. The results of these experiments have shown that this effect may be localized in the gamma phase at shock pressures in the region of 5 GP and above.

A numerical solution of the problem of crown forest fire initiation and spread

NASA Astrophysics Data System (ADS)

Marzaeva, S. I.; Galtseva, O. V.

2018-05-01

Mathematical model of forest fire was based on an analysis of known experimental data and using concept and methods from reactive media mechanics. The study takes in to account the mutual interaction of the forest fires and three-dimensional atmosphere flows. The research is done by means of mathematical modeling of physical processes. It is based on numerical solution of Reynolds equations for chemical components and equations of energy conservation for gaseous and condensed phases. It is assumed that the forest during a forest fire can be modeled as a two-temperature multiphase non-deformable porous reactive medium. A discrete analog for the system of equations was obtained by means of the control volume method. The developed model of forest fire initiation and spreading would make it possible to obtain a detailed picture of the variation in the velocity, temperature and chemical species concentration fields with time. Mathematical model and the result of the calculation give an opportunity to evaluate critical conditions of the forest fire initiation and spread which allows applying the given model for of means for preventing fires.

Multiple Sclerosis: Molecular Mechanisms and Therapeutic Opportunities

PubMed Central

Miljković, Djordje; Spasojević, Ivan

2013-01-01

Abstract The pathophysiology of multiple sclerosis (MS) involves several components: redox, inflammatory/autoimmune, vascular, and neurodegenerative. All of them are supported by the intertwined lines of evidence, and none of them should be written off. However, the exact mechanisms of MS initiation, its development, and progression are still elusive, despite the impressive pace by which the data on MS are accumulating. In this review, we will try to integrate the current facts and concepts, focusing on the role of redox changes and various reactive species in MS. Knowing the schedule of initial changes in pathogenic factors and the key turning points, as well as understanding the redox processes involved in MS pathogenesis is the way to enable MS prevention, early treatment, and the development of therapies that target specific pathophysiological components of the heterogeneous mechanisms of MS, which could alleviate the symptoms and hopefully stop MS. Pertinent to this, we will outline (i) redox processes involved in MS initiation; (ii) the role of reactive species in inflammation; (iii) prooxidative changes responsible for neurodegeneration; and (iv) the potential of antioxidative therapy. Antioxid. Redox Signal. 19, 2286–2334. PMID:23473637

The time course of body temperature, serum amyloid A protein, C-reactive protein and interleukin-6 in patients with bacterial infection during the initial 3 days of antibiotic therapy.

PubMed

Lannergård, Anders; Viberg, Anders; Cars, Otto; Karlsson, Mats O; Sandström, Marie; Larsson, Anders

2009-01-01

The accuracy of using body temperature, serum amyloid A (SAA), C-reactive protein (CRP) and interleukin-6 (IL-6) in the work-up for early or late step-down therapy after an initial course of intravenous cefuroxime was investigated. Eighty-one hospitalized patients with an initial course of cefuroxime were retrospectively classified with one of the following diagnoses: bacterial infection without known focus, pneumonia, bronchitis, pyelonephritis, skin and soft-tissue infections or fever of other origin. The majority of the patients had sepsis (91% or 74/81) of whom 6 patients had severe sepsis. The inter-individual variability of body temperature, SAA, CRP and IL-6 was considerable. The time course of SAA and CRP during the first 24 h in patients with sepsis with a short duration of illness but without septic shock showed increasing levels during the initial course of intravenous therapy. In contrast, body temperature and IL-6 decreased, regardless of illness duration. Beyond 24 h, all 4 biomarkers declined, again regardless of the duration of illness. After the initial course of cefuroxime, biomarkers were non-distinguishing in terms of guidance in the judgement of early or late step-down therapy. Further studies are proposed for biomarker guidance antibiotic therapy in sepsis patients without septic shock.

[An evaluation of the clinical competence of a population of specialist physicians educated by the medical internship and residency system].

PubMed

Pujol, R; Busquet, J; Feliu, E; Castellsague, J; Gómez Sáez, J M; Martínez Carretero, J M; Rozman, C

1995-10-21

The quality of physicians who have undergone resident official training (MIR) should logically be better than that of the remaining physicians who were not able to enter into this official training. The present study was designed with the aim of verifying this hypothesis. A sample of physicians who underwent the MIR examination in 1982 and who upon passing the same were permitted to initiate the MIR training in 1983 was selected. The group was subdivided into MIR and no MIR and according to the specialty followed. When the physicians were practicing as specialists two types of surveys were carried out with one being by telephone and the other personal in which the personal characteristics, preparation for the MIR test, professional satisfaction and personal motivation were analyzed. The pharmaceutic prescriptions of both groups were analyzed according to indicators of the Servei Català de la Salut (Catalonian Health Service) and the opinion of colleagues of each of the members of each group was evaluated with another questionnaire. The written resolution of hypothetical clinical cases were given to each of the individuals included. A level of global competence defined as a percentage for the following components was identified using: curricular evaluation (10%), professional satisfaction (20%), personal motivation (10%), hypothetical case resolution (35%) and peer opinion (25%). The global competence of the physicians trained under the MIR system was greater than that of the no MIR group (p < 0.01). On analysis by sections the differences of greatest note were observed in the resolution of hypothetical cases (p < 0.0001), curricular evaluation (p < 0.0001) and the quality of pharmaceutical prescription (p < 0.0001). The differences were less of note in comparison of personal motivation (p < 0.02) and professional satisfaction (p < 0.02). No differences were observed in peer opinion. The professional quality of physicians trained by MIR who presented for the 1982 examination in Catalonia and practiced in medical specialties is greater than that of a comparable group with regard to professional practice.

Population Modeling of Modified Risk Tobacco Products Accounting for Smoking Reduction and Gradual Transitions of Relative Risk.

PubMed

Poland, Bill; Teischinger, Florian

2017-11-01

As suggested by the Food and Drug Administration (FDA) Modified Risk Tobacco Product (MRTP) Applications Draft Guidance, we developed a statistical model based on public data to explore the effect on population mortality of an MRTP resulting in reduced conventional cigarette smoking. Many cigarette smokers who try an MRTP persist as dual users while smoking fewer conventional cigarettes per day (CPD). Lower-CPD smokers have lower mortality risk based on large cohort studies. However, with little data on the effect of smoking reduction on mortality, predictive modeling is needed. We generalize prior assumptions of gradual, exponential decay of Excess Risk (ER) of death, relative to never-smokers, after quitting or reducing CPD. The same age-dependent slopes are applied to all transitions, including initiation to conventional cigarettes and to a second product (MRTP). A Monte Carlo simulation model generates random individual product use histories, including CPD, to project cumulative deaths through 2060 in a population with versus without the MRTP. Transitions are modeled to and from dual use, which affects CPD and cigarette quit rates, and to MRTP use only. Results in a hypothetical scenario showed high sensitivity of long-run mortality to CPD reduction levels and moderate sensitivity to ER transition rates. Models to project population effects of an MRTP should account for possible mortality effects of reduced smoking among dual users. In addition, studies should follow dual-user CPD histories and quit rates over long time periods to clarify long-term usage patterns and thereby improve health impact projections. We simulated mortality effects of a hypothetical MRTP accounting for cigarette smoking reduction by smokers who add MRTP use. Data on relative mortality risk versus CPD suggest that this reduction may have a substantial effect on mortality rates, unaccounted for in other models. This effect is weighed with additional hypothetical effects in an example. © The Author 2017. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The potential impact of gender stereotypes for nursing research.

PubMed

Hicks, C

1996-11-01

The move towards evidence-based health care has meant an increasing pressure on paramedical professionals to become more research aware and research active. However, despite various initiatives designed to encourage research, there remains within nursing a notable paucity of relevant published research. While numerous explanations have been put forward in an attempt to account for this shortfall, they have tended to focus on structural/organizational barriers rather than difficulties located at the individual level. However, Hicks, in studies of midwives and nurse managers suggests that one critical perspective may be the stereotypes and assumptions associated with the nursing profession, these being so diametrically opposed to the core skills required of researchers that they operate as a natural deterrent to research activities of any sort. Embedded within this theory is the notion of gender roles, which are archetypally feminine for nursing yet archetypally masculine for research. However, Hicks' studies, which were both variants of Asch's Central Trait Theory, focused on women both as the hypothetical subject of the exercise involved and as participants. If research is bound up with gender attributions in the way she suggests, it would be necessary to ask if this is still relevant when the gender of the hypothetical figure at the centre of the study is changed. To this end, the present study was conducted which, apart from the modification just highlighted, was a replication of Hicks' earlier studies. In brief, two groups of participants rated a hypothetical male candidate for a nursing post along 15 bipolar dimensions. The candidate had been described by his referee using six adjectives, of which five were identical for each group. However, the final phrase used to describe the first group's candidate was "good clinician' while for the second group it was "good researcher'. The ratings given by the two groups along the 15 dimensions were then compared. It was found that the male applicant described as a good researcher was assumed to be more successful, more ambitious, more confident and more ruthless than one described as a good clinician. The implications of these results are discussed in relation to gender theories and nursing research.

STAT3 labels a subpopulation of reactive astrocytes required for brain metastasis.

PubMed

Priego, Neibla; Zhu, Lucía; Monteiro, Cátia; Mulders, Manon; Wasilewski, David; Bindeman, Wendy; Doglio, Laura; Martínez, Liliana; Martínez-Saez, Elena; Cajal, Santiago Ramón Y; Megías, Diego; Hernández-Encinas, Elena; Blanco-Aparicio, Carmen; Martínez, Lola; Zarzuela, Eduardo; Muñoz, Javier; Fustero-Torres, Coral; Pineiro, Elena; Hernández-Laín, Aurelio; Bertero, Luca; Poli, Valeria; Sánchez-Martínez, Melchor; Menendez, Javier A; Soffietti, Riccardo; Bosch-Barrera, Joaquim; Valiente, Manuel

2018-06-11

The brain microenvironment imposes a particularly intense selective pressure on metastasis-initiating cells, but successful metastases bypass this control through mechanisms that are poorly understood. Reactive astrocytes are key components of this microenvironment that confine brain metastasis without infiltrating the lesion. Here, we describe that brain metastatic cells induce and maintain the co-option of a pro-metastatic program driven by signal transducer and activator of transcription 3 (STAT3) in a subpopulation of reactive astrocytes surrounding metastatic lesions. These reactive astrocytes benefit metastatic cells by their modulatory effect on the innate and acquired immune system. In patients, active STAT3 in reactive astrocytes correlates with reduced survival from diagnosis of intracranial metastases. Blocking STAT3 signaling in reactive astrocytes reduces experimental brain metastasis from different primary tumor sources, even at advanced stages of colonization. We also show that a safe and orally bioavailable treatment that inhibits STAT3 exhibits significant antitumor effects in patients with advanced systemic disease that included brain metastasis. Responses to this therapy were notable in the central nervous system, where several complete responses were achieved. Given that brain metastasis causes substantial morbidity and mortality, our results identify a novel treatment for increasing survival in patients with secondary brain tumors.

Respiratory sinus arrhythmia reactivity to a sad film predicts depression symptom improvement and symptomatic trajectory.

PubMed

Panaite, Vanessa; Hindash, Alexandra Cowden; Bylsma, Lauren M; Small, Brent J; Salomon, Kristen; Rottenberg, Jonathan

2016-01-01

Respiratory sinus arrhythmia (RSA) reactivity, an index of cardiac vagal tone, has been linked to self-regulation and the severity and course of depression (Rottenberg, 2007). Although initial data supports the proposition that RSA withdrawal during a sad film is a specific predictor of depression course (Fraguas, 2007; Rottenberg, 2005), the robustness and specificity of this finding are unclear. To provide a stronger test, RSA reactivity to three emotion films (happy, sad, fear) and to a more robust stressor, a speech task, were examined in currently depressed individuals (n=37), who were assessed for their degree of symptomatic improvement over 30weeks. Robust RSA reactivity to the sad film uniquely predicted overall symptom improvement over 30weeks. RSA reactivity to both sad and stressful stimuli predicted the speed and maintenance of symptomatic improvement. The current analyses provide the most robust support to date that RSA withdrawal to sad stimuli (but not stressful) has specificity in predicting the overall symptomatic improvement. In contrast, RSA reactivity to negative stimuli (both sad and stressful) predicted the trajectory of depression course. Patients' engagement with sad stimuli may be an important sign to attend to in therapeutic settings. Copyright © 2015 Elsevier B.V. All rights reserved.

Preliminary evidence of attenuated blood pressure reactivity to acute stress in adults following a recent marital separation.

PubMed

Grinberg, Austin M; O'Hara, Karey L; Sbarra, David A

2018-03-01

This study explores cardiovascular reactivity during an acute-stress task in a sample of recently separated adults. In a cross-sectional design, we examined the association between adults' subjective separation-related distress and changes in heart rate and blood pressure across the acute-stress laboratory paradigm in a sample of 133 (n = 49 men) recently separated adults. Heart rate (HR) and Blood pressure (BP) were recorded across a resting baseline period, a math stressor task, and a recovery period. Multilevel analyses revealed that adults who reported greater separation-related distress exhibited higher initial BP and a slower linear increase in BP across the study period. In addition, adults reporting greater separation-related distress evidenced significantly slower declines in diastolic blood pressure (DBP) following the acute-stress task. HR reactivity was not moderated by separation-related distress. In recently separated adults, preliminary evidence suggests that the context of the stressors may reveal differential patterns of problematic reactivity (exaggerated or blunted responding). Greater emotional intrusion and hyperactivity symptoms may index increased risk for blunted cardiovascular reactivity to general stressors. This pattern of reactivity is consistent with models of allostatic load that emphasise the deleterious effect of hyporesponsivity to environmental demands.

Immunological Reactivity Using Monoclonal and Polyclonal Antibodies of Autoimmune Thyroid Target Sites with Dietary Proteins

PubMed Central

Herbert, Martha

2017-01-01

Many hypothyroid and autoimmune thyroid patients experience reactions with specific foods. Additionally, food interactions may play a role in a subset of individuals who have difficulty finding a suitable thyroid hormone dosage. Our study was designed to investigate the potential role of dietary protein immune reactivity with thyroid hormones and thyroid axis target sites. We identified immune reactivity between dietary proteins and target sites on the thyroid axis that includes thyroid hormones, thyroid receptors, enzymes, and transport proteins. We also measured immune reactivity of either target specific monoclonal or polyclonal antibodies for thyroid-stimulating hormone (TSH) receptor, 5′deiodinase, thyroid peroxidase, thyroglobulin, thyroxine-binding globulin, thyroxine, and triiodothyronine against 204 purified dietary proteins commonly consumed in cooked and raw forms. Dietary protein determinants included unmodified (raw) and modified (cooked and roasted) foods, herbs, spices, food gums, brewed beverages, and additives. There were no dietary protein immune reactions with TSH receptor, thyroid peroxidase, and thyroxine-binding globulin. However, specific antigen-antibody immune reactivity was identified with several purified food proteins with triiodothyronine, thyroxine, thyroglobulin, and 5′deiodinase. Laboratory analysis of immunological cross-reactivity between thyroid target sites and dietary proteins is the initial step necessary in determining whether dietary proteins may play a potential immunoreactive role in autoimmune thyroid disease. PMID:28894619

Quantum Gravity in Cyclic (ekpyrotic) and Multiple (anthropic) Universes with Strings And/or Loops

NASA Astrophysics Data System (ADS)

Chung, T. J.

2008-09-01

This paper addresses a hypothetical extension of ekpyrotic and anthropic principles, implying cyclic and multiple universes, respectively. Under these hypotheses, from time immemorial (t = -∞), a universe undergoes a big bang from a singularity, initially expanding and eventually contracting to another singularity (big crunch). This is to prepare for the next big bang, repeating these cycles toward eternity (t = +∞), every 30 billion years apart. Infinity in time backward and forward (t = ±∞) is paralleled with infinity in space (Xi = ±∞), allowing multiple universes to prevail, each undergoing big bangs and big crunches similarly as our own universe. It is postulated that either string theory and /or loop quantum gravity might be able to substantiate these hypotheses.

Modeling experiments on the deceleration and reactivation of Kangerlussuup Sermusa, West Greenland

NASA Astrophysics Data System (ADS)

Rezvanbehbahani, S.; Stearns, L. A.; van der Veen, C. J.; Catania, G. A.

2015-12-01

Seasonal variations in outlet glacier velocity due to basal sliding are well-documented and typically involve acceleration early in the melt season due to enhanced sliding as a result of inefficient drainage of surface water reaching the bed. However, velocity observations from Kangerlussuup Sermusa (KS) in West Greenland contradict this pattern. Instead, ice velocity at KS shows no significant change in early spring compared with the previous winter. This sluggish response of the glacier to spring melt is often followed by an extreme, and short-lived, deceleration. For example, in August 2010, the lower 20 km of the trunk decelerated from about 1600 m a-1 to less than 250 m a-1; this event was followed by a rapid reactivation back to the previous velocity in less than 60 days. Available records since 2006 show that the sequence of steady spring velocity, followed by summer deceleration, and rapid fall reactivation occurs annually; however, the magnitudes of deceleration vary. In this regard, the response of KS to regional environmental forcings is unique compared to its neighboring glaciers. In this study, we investigate whether the unique behavior of KS can be explained by the interaction between changes in basal conditions and the local geometry of the glacier. We model the glacier flow by solving full-Stokes equations using the finite element method in the open-source FEniCS framework. Assuming isothermal ice within the lower trunk, we run experiments on the mechanical properties and boundary conditions of the glacier. These experiments include spatio-temporal changes in basal slipperiness, periodic melt-water influx to the bed, and ice viscosity variations due to changes in melt-water supply to the bed. We also conduct sensitivity analyses on the glacier flow with different ice geometries (e.g. thickness and surface slope) to investigate conditions under which we can produce the unique seasonal behavior of KS. Finally, we assess the impact of the combination of these parameters on the ice flow and evaluate the credibility of our hypothetical scenarios based on available measurements.

Catalytic Isonitrile Insertions and Condensations Initiated by RNC–X Complexation

PubMed Central

Fleming, Fraser F.

2014-01-01

Isonitriles are delicately poised chemical entities capable of being coaxed to react as nucleophiles or electrophiles. Directing this tunable reactivity with metal and non-metal catalysts provides rapid access to a large array of complex nitrogenous structures ideally functionalized for medicinal applications. Isonitrile insertion into transition metal complexes has featured in numerous synthetic and mechanistic studies, leading to rapid deployment of isonitriles in numerous catalytic processes, including multicomponent reactions (MCR). Covering the literature from 1990–2014, the present review collates reaction types to highlight reactivity trends and allow catalyst comparison. PMID:25484847

Speciation study in the sulfamethoxazole-copper-pH-soil system: implications for retention prediction.

PubMed

Morel, Marie-Christine; Spadini, Lorenzo; Brimo, Khaled; Martins, Jean M F

2014-05-15

Sulfamethoxazole (SMX) is a persistent sulfonamide antibiotic drug used in the veterinary and human medical sectors and is widely detected in natural waters. To better understand the reactive transport of this antibiotic in soil, the speciation of the SMX-Cu(II)-H(+) system in solution and the combined sorption of these components in a natural vineyard soil were investigated by acid-base titrimetry and infrared spectroscopy. Cu(II) is considered to represent a strongly complexing trace element cation (such as Cd(2+), Zn(2+), Pb(2+), Ni(2+), etc.) in comparison to more prevalent but more weakly binding cations (such as Ca(2+) and Mg(2+)). Titrimetric studies showed that, relative to other antibiotics, such as tetracycline, SMX is a weak copper chelating agent and a weak soil sorbent at the soil pH (pH6). However, the sorption of SMX in soil increases strongly (by a factor of 6) in the presence of copper. This finding strongly supports the hypothetical formation of ternary SMX-Cu-soil complexes, especially considering that copper is dominantly sorbed in a state at pH6. The data were successfully modelled with PhreeqC assuming the existence of binary and ternary surface complexes in equilibrium with aqueous Cu, SMX and Cu-SMX complexes. It is thought that other strongly complexing cations present on the surface of reactive organic and mineral soil phases, such as Cd(II), Ni(II), Zn(II), Pb(II), Fe(II/III), Mn(II/IV) and Al(III), affect the solid/solution partitioning of SMX. This study thus suggests that surface-adsorbed cations significantly increase the sorption of SMX. Copyright © 2014 Elsevier B.V. All rights reserved.

Atomic resolution x-ray structure of the substrate recognition domain of higher plant ribulose-bisphosphate carboxylase/oxygenase (Rubisco) activase.

PubMed

Henderson, J Nathan; Kuriata, Agnieszka M; Fromme, Raimund; Salvucci, Michael E; Wachter, Rebekka M

2011-10-14

The rapid release of tight-binding inhibitors from dead-end ribulose-bisphosphate carboxylase/oxygenase (Rubisco) complexes requires the activity of Rubisco activase, an AAA+ ATPase that utilizes chemo-mechanical energy to catalyze the reactivation of Rubisco. Activase is thought to play a central role in coordinating the rate of CO(2) fixation with the light reactions of photosynthesis. Here, we present a 1.9 Å crystal structure of the C-domain core of creosote activase. The fold consists of a canonical four-helix bundle, from which a paddle-like extension protrudes that entails a nine-turn helix lined by an irregularly structured peptide strand. The residues Lys-313 and Val-316 involved in the species-specific recognition of Rubisco are located near the tip of the paddle. An ionic bond between Lys-313 and Glu-309 appears to stabilize the glycine-rich end of the helix. Structural superpositions onto the distant homolog FtsH imply that the paddles extend away from the hexameric toroid in a fan-like fashion, such that the hydrophobic sides of each blade bearing Trp-302 are facing inward and the polar sides bearing Lys-313 and Val-316 are facing outward. Therefore, we speculate that upon binding, the activase paddles embrace the Rubisco cylinder by placing their hydrophobic patches near the partner protein. This model suggests that conformational adjustments at the remote end of the paddle may relate to selectivity in recognition, rather than specific ionic contacts involving Lys-313. Additionally, the superpositions predict that the catalytically critical Arg-293 does not interact with the bound nucleotide. Hypothetical ring-ring stacking and peptide threading models for Rubisco reactivation are briefly discussed.

Immunogenic proteins of Brucella abortus to minimize cross reactions in brucellosis diagnosis.

PubMed

Ko, Kyung Yuk; Kim, Jong-Wan; Her, Moon; Kang, Sung-Il; Jung, Suk Chan; Cho, Dong Hee; Kim, Ji-Yeon

2012-05-04

To overcome the limitations of serological diagnosis, including false positive reactions caused by other pathogens, specific antigens for diagnosis of brucellosis other than LPS have been required. The present study was conducted to separate and identify immuno-dominant insoluble proteins of Brucella abortus against the antisera of cattle infected with B. abortus, or/and Yersinia enterocolitica, or the sera of non-infected cattle. After separating insoluble proteins of B. abortus by two dimensional electrophoresis (2-DE), their immuno-reactivity was determined by western blotting. A portion of the immunogenic spots against the positive antisera of B. abortus that have the potential for use as specific antigens were identified by MS/MS analysis. Overall, 18 immunogenic insoluble proteins of B. abortus 1119-3 showed immuno-reactivity against only the positive antisera of B. abortus, but failed to have immunogenicity toward both the positive sera of Y. enterocolitica and the negative sera of B. abortus. Identification of these proteins revealed the following: F0F1 ATP synthase subunit β, solute-binding family 5 protein, 28 kDa OMP, Leu/Ile/Val-binding family protein, Histidinol dehyddrogenase, Hypothetical protein, Twin-arginine translocation pathway signal sequence domain-containing protein, Dihydroorotase, Serine protease family protein, β-hydroxyacyl-(acyl-carrier-protein) dehydratase FabA, Short-chain dehydrogenase-/reductase carbonic anhydrase, Orinithine carbamoyltransferase, Leucyl aminopeptidase, Cold shock DNA-binding domain-containing protein, Cu/Zn superoxide dismutase, and Methionine aminopeptidase. The 18 immunogenic proteins separated in the present study can be considered candidate antigens to minimize cross reaction in the diagnosis of brucellosis and useful sources for Brucella vaccine development. Copyright © 2011 Elsevier B.V. All rights reserved.

Effect of Control Blade History, and Axial Coolant Density and Burnup Profiles on BWR Burnup Credit

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

Ade, Brian J; Marshall, William BJ J; Martinez-Gonzalez, Jesus S

Oak Ridge National Laboratory (ORNL) and the US Nuclear Regulatory Commission (NRC) have initiated a multiyear project to investigate the application of burnup credit (BUC) for boiling water reactor (BWR) fuel in storage and transportation systems (often referred to as casks) and spent fuel pools (SFPs). This work is divided into two main phases. The first phase investigated the applicability of peak reactivity methods currently used in SFPs to transportation and storage casks and the validation of reactivity calculations and spent fuel compositions within these methods. The second phase focuses on extending BUC beyond peak reactivity. This paper documents themore » analysis of the effects of control blade insertion history, and moderator density and burnup axial profiles for extended BWR BUC.« less

Effects of reactive oxygen species and interplay of antioxidants during physical exercise in skeletal muscles.

PubMed

Thirupathi, Anand; Pinho, Ricardo A

2018-05-01

A large number of researches have led to a substantial growth of knowledge about exercise and oxidative stress. Initial investigations reported that physical exercise generates free radical-mediated damages to cells; however, in recent years, studies have shown that regular exercise can upregulate endogenous antioxidants and reduce oxidative damage. Yet, strenuous exercise perturbs the antioxidant system by increasing the reactive oxygen species (ROS) content. These alterations in the cellular environment seem to occur in an exercise type-dependent manner. The source of ROS generation during exercise is debatable, but now it is well established that both contracting and relaxing skeletal muscles generate reactive oxygen species and reactive nitrogen species. In particular, exercises of higher intensity and longer duration can cause oxidative damage to lipids, proteins, and nucleotides in myocytes. In this review, we summarize the ROS effects and interplay of antioxidants in skeletal muscle during physical exercise. Additionally, we discuss how ROS-mediated signaling influences physical exercise in antioxidant system.

Reactive Resonances in N+N2 Exchange Reaction

NASA Technical Reports Server (NTRS)

Wang, Dunyou; Huo, Winifred M.; Dateo, Christopher E.; Schwenke, David W.; Stallcop, James R.

2003-01-01

Rich reactive resonances are found in a 3D quantum dynamics study of the N + N2 exchange reaction using a recently developed ab initio potential energy surface. This surface is characterized by a feature in the interaction region called Lake Eyring , that is, two symmetric transition states with a shallow minimum between them. An L2 analysis of the quasibound states associated with the shallow minimum confirms that the quasibound states associated with oscillations in all three degrees of freedom in Lake Eyring are responsible for the reactive resonances in the state-to-state reaction probabilities. The quasibound states, mostly the bending motions, give rise to strong reasonance peaks, whereas other motions contribute to the bumps and shoulders in the resonance structure. The initial state reaction probability further proves that the bending motions are the dominating factors of the reaction probability and have longer life times than the stretching motions. This is the first observation of reactive resonances from a "Lake Eyring" feature in a potential energy surface.

Parallelism Effects and Verb Activation: The Sustained Reactivation Hypothesis

PubMed Central

Shapiro, Lewis P.; Love, Tracy

2010-01-01

This study investigated the processes underlying parallelism by evaluating the activation of a parallel element (i.e., a verb) throughout and-coordinated sentences. Four points were tested: (1) approximately 1,600ms after the verb in the first conjunct (PP1), (2) immediately following the conjunction (PP2), (3) approximately 1,100ms after the conjunction (PP3), (4) at the end of the second conjunct (PP4). The results revealed no activation at PP1, suggesting activation related to the initial presentation had decayed by this point; however, activation was observed at PP2, PP3, and PP4, suggesting the conjunction elicits reactivation that is sustained throughout the second conjunct. These findings support a specific hypothesis about parallelism, the sustained reactivation hypothesis. This hypothesis claims that, in conjoined structures, a cue that is associated with parallelism elicits the reactivation of material from the first conjunct and that this activation is sustained until integration with the second conjunct can be completed. PMID:19774464

Parallelism effects and verb activation: the sustained reactivation hypothesis.

PubMed

Callahan, Sarah M; Shapiro, Lewis P; Love, Tracy

2010-04-01

This study investigated the processes underlying parallelism by evaluating the activation of a parallel element (i.e., a verb) throughout and-coordinated sentences. Four points were tested: (1) approximately 1,600 ms after the verb in the first conjunct (PP1), (2) immediately following the conjunction (PP2), (3) approximately 1,100 ms after the conjunction (PP3), (4) at the end of the second conjunct (PP4). The results revealed no activation at PP1, suggesting activation related to the initial presentation had decayed by this point; however, activation was observed at PP2, PP3, and PP4, suggesting the conjunction elicits reactivation that is sustained throughout the second conjunct. These findings support a specific hypothesis about parallelism, the sustained reactivation hypothesis. This hypothesis claims that, in conjoined structures, a cue that is associated with parallelism elicits the reactivation of material from the first conjunct and that this activation is sustained until integration with the second conjunct can be completed.

Importance of asparagine on the conformational stability and chemical reactivity of selected anti-inflammatory peptides

NASA Astrophysics Data System (ADS)

Soriano-Correa, Catalina; Barrientos-Salcedo, Carolina; Campos-Fernández, Linda; Alvarado-Salazar, Andres; Esquivel, Rodolfo O.

2015-08-01

Inflammatory response events are initiated by a complex series of molecular reactions that generate chemical intermediaries. The structure and properties of peptides and proteins are determined by the charge distribution of their side chains, which play an essential role in its electronic structure and physicochemical properties, hence on its biological functionality. The aim of this study was to analyze the effect of changing one central amino acid, such as substituting asparagine for aspartic acid, from Cys-Asn-Ser in aqueous solution, by assessing the conformational stability, physicochemical properties, chemical reactivity and their relationship with anti-inflammatory activity; employing quantum-chemical descriptors at the M06-2X/6-311+G(d,p) level. Our results suggest that asparagine plays a more critical role than aspartic acid in the structural stability, physicochemical features, and chemical reactivity of these tripeptides. Substituent groups in the side chain cause significant changes on the conformational stability and chemical reactivity, and consequently on their anti-inflammatory activity.

Shock Response and Explosive Launch of Compacted Reactive Material

NASA Astrophysics Data System (ADS)

Molitoris, John; Gash, Alexander; Garza, Raul; Gagliardi, Franco; Tringe, Joseph; Batteux, Jan; Souers, P.; HEAF Team

2013-06-01

We have performed a series of experiments investigating the detailed dynamic response of compacted reactive material to shock and blast. Here a granular reactive formulation (Fe2O3/Al based thermite) was pressed into a solid cylinder of material and mated to a high-explosive charge of the same diameter. Detonation of the charge transmitted a shock wave to the thermite cylinder and imparted momentum launching it in the direction of the detonation. High-resolution time sequence radiography was used to image the dynamic response of the thermite. This technique allowed a detailed investigation of material deformation in addition to changes in the internal structure and indications of reactivity. The effect of variations in the initial density of the pressed thermite was also examined. We find that these pressed thermites behave much like solid metals during shock transit, then respond much differently. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

A Method for Preparation, Storage and Activation of Large Populations of Immotile Sea Urchin Sperm

NASA Technical Reports Server (NTRS)

Bracho, Geracimo E.; Fritch, Jennifer J.; Tash, Joseph S.

1997-01-01

Reversible protein phosphorylation is associated with initiation and modulation of sperm flagellar motility. Many studies aimed at examining the signal transduction mechanisms underlying the expression of motility have relied on detergent-permeabilized sperm reactivated with exogenous 32 P-ATP. However, the reactivation conditions allow variable levels of motility to be expressed and phosphorylation of many proteins that appear to be unrelated to sperm motility. Thus, identification of the few relevant proteins is difficult. We have developed a method to collect and keep sperm immotile until reactivated for analysis to normal motility levels. Artificial sea water (ASW) buffered with 5 mM 2-[N-morpholino]ethanesulfonic acid at pH 6.0 and containing 50 mM KCI, allows collection and storage of immotile sea urchin sperm for up to 96 h at 4-5 C. Motility under these conditions is essentially zero, but sperm is rapidly reactivated to normal motility by diluting with ASW to standard pH (8.0) and KCI concentration (10 mM).

Scleroderma Autoantigens Are Uniquely Fragmented by Metal-catalyzed Oxidation Reactions: Implications for Pathogenesis

PubMed Central

Casciola-Rosen, Livia; Wigley, Fredrick; Rosen, Antony

1997-01-01

The observation that revelation of immunocryptic epitopes in self antigens may initiate the autoimmune response has prompted the search for processes which induce novel fragmentation of autoantigens as potential initiators of autoimmunity. The reversible ischemia reperfusion which characterizes scleroderma has focused attention on reactive oxygen species as molecules which might induce autoantigen fragmentation. We demonstrate that several of the autoantigens targeted in diffuse scleroderma are uniquely susceptible to cleavage by reactive oxygen species, in a metal-dependent manner. Multiple features of the fragmentation reaction and its inhibition indicate that these autoantigens possess metal-binding sites, which focus metal-catalyzed oxidation reactions (and consequent fragmentation) to specific regions of the antigens. These data suggest that the autoantibody response in scleroderma is the immune marker of unique protein fragmentation, induced by ischemia reperfusion in the presence of appropriate metals, and focus attention on abnormal metal status as a potential pathogenic principle in this disease. PMID:8996243

Preparation of Chitosan Coated Magnetic Hydroxyapatite Nanoparticles and Application for Adsorption of Reactive Blue 19 and Ni2+ Ions

PubMed Central

Nguyen, Van Cuong; Pho, Quoc Hue

2014-01-01

An adsorbent called chitosan coated magnetic hydroxyapatite nanoparticles (CS-MHAP) was prepared with the purpose of improvement for the removal of Ni2+ ions and textile dye by coprecipitation. Structure and properties of CS-MHAP were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). Weight percent of chitosan was investigated by thermal gravimetric analysis (TGA). The prepared CS-MHAP presents a significant improvement on the removal efficiency of Ni2+ ions and reactive blue 19 dye (RB19) in comparison with chitosan and magnetic hydroxyapatite nanoparticles. Moreover, the adsorption capacities were affected by several parameters such as contact time, initial concentration, adsorbent dosage, and initial pH. Interestingly, the prepared adsorbent could be easily recycled from an aqueous solution by an external magnet and reused for adsorption with high removal efficiency. PMID:24592158